AAS Meetings: If you're here, you probably already know that Star X is a mid X concept that is in a finalist is a finalist in a phase, a study right now, and we are really excited to tell you a little bit about the mission, so we will start with Ann Horns. Meyer, who is the deputy?
AAS Meetings: Thank you.
AAS Meetings: Yeah. And I should say there was supposed to be a correction to the program. Will Zhang is not here, so we hope to end a couple of minutes early on the for this program. Okay. So just to start off with.
AAS Meetings: there's going to be
AAS Meetings: the talks listed in rainbow colors Here i'm giving an overview of the mission. But then we're going to go over the observing plan. Edmund Hodges cluck speaking after me, and then 3 of our science team members.
AAS Meetings: We'll tell you about the observing plans under our our our plan science program. But in addition to that. Please go visit Session, 112, the poster session for more details. We have a lot more details about the mission, and i'll put this QR. Code up again so that you can visit our Star X website.
AAS Meetings: Okay. So the proposed Star Exhibition, studying the fast. furious and forming universe.
I like to put a picture of myself up here because I tend to keep my mask on. That's what I look like. There's that QR. Code again. This is the cover. From our submitted step. One proposal for the midx, 300 milliondollar opportunity for a mission and
Star X, which we don't often say the full name is Survey and Time domain, astrophysics, research Explorer. So we do surveys in the Time Domain, and there's quite a bit that's enabled by this. So we submitted this proposal. December of 2,021.
AAS Meetings: The P I was Will Zhang is still well sighing. I'm the deputy pi, and the big news in August was that there was a down select, and we are one of 2 teams in a competitive phase, a study. It's been a whirlwind fun time doing this more in depth study of this mission.
AAS Meetings: and this process will be completed later this year.
AAS Meetings: So this is an ultraviolet and X-ray Mission. At all moments we are observing, both in the X-rays and in the ultraviolet over a roughly one square degree field of view.
AAS Meetings: This is what we envision. Star x will look like. so to point out the key features. Here we have an X-ray telescope and con focal with the X-ray telescope. We have an ultraviolet telescope. There, on the side of the spacecraft.
AAS Meetings: the major partners, NASA Goddard Space Flight Center is leading Ball aerospace is providing the spacecraft mit Caveley is providing the X-ray instrument
AAS Meetings: and University of Colorado Las is providing the ultraviolet telescope and mission operations.
AAS Meetings: And I'm happy to announce that we also have partnering on our mission, the Italian Space Agency, Ozzy. We'll be providing ground station contacts through Melindi as well as science, analysis Software and pipeline support for the Mission.
AAS Meetings: Oh, and I wanted to mention one additional thing here that soon I will be adding the logo for mpe, that is also contributing x-ray calibration support for our mirrors.
AAS Meetings: So in the next version of this talk at the American Physical Society month, next month you'll see an mpe logo
AAS Meetings: all right. So this is our science team. They've been working very hard during phase a. As we refine and update our plans, and as we refine and update our design, they've been responsive to those changes.
AAS Meetings: They've been working very hard, and we are very grateful to them, and several of them in the audience, and are going to be speaking after me. So the themes exploring the fast, furious, and forming universe.
AAS Meetings: So the first 2, the fast and the furious, the fast return refers to events like supernova shock breakouts extremely rare events that tell us a lot about astrophysics as well as stellar flares that affect exoplanet habitability.
AAS Meetings: and the electromagnetic emission from neutron star mergers. You have to have a very flexible and fast observatory to be able to observe these things.
AAS Meetings: The second theme is the furious.
AAS Meetings: rapidly accrediting black holes. We want to understand accretion and the poster child picture here is for title, disruption, events. And again, we want to do Time Domain studies so that we can
AAS Meetings: capture as many possible title, disruption, events, and also by doing time, domain, repeat observations, we can do things like agn reverberation, mapping, and X-ray and UV to understand accretion, disk structure.
AAS Meetings: And if you build up over time a cadence survey where you're catching all these transient events, you do eventually go deep. So we have a 350 square degree survey and a 13 square degree survey that we visit weekly
AAS Meetings: and daily. and by the end of the 2 years we've gone very, very deep.
AAS Meetings: and that leads to the forming. We will have very deep. X-ray maps over large areas
AAS Meetings: that will allow us to study clusters of galaxies. We can also do targeted observations of clusters of galaxies to understand the formation of the most massive structures in the universe. I'm going to highlight some of the science, and we will collectively highlight some of the science.
AAS Meetings: But there's a lot you can do with approximately a square degree field of View and the X-ray and UV. And this is just our plan for the first 2 years, and the mission and our science objectives. There's so much more you can do with this mission.
AAS Meetings: So this is what the mission looks like. This is an updated CAD rendering of our spacecraft
AAS Meetings: so 3 largely independent systems, the X-ray telescope. the ultraviolet telescope, and the spacecraft that can be put together in a plug and play fashion. I already described the responsibilities.
AAS Meetings: but I wanted to give you a little bit of idea of the dimension. If you've seen this talk before we've had a little bit of a design, update our wingspans, now a little bit shorter at 5 and a half meters, and the total length is about 6.2, 4 meters, just for perspective.
AAS Meetings: and Something that's very important to our mission is that we are fast slewing and have fast target of opportunity response.
AAS Meetings: Our Our requirement is to observe targets, targets of opportunity with when 120 min, 80% of the time you can think of this as a legal requirement. We have to write something down that we know we can do.
AAS Meetings: but most of the time we expect to do better than that.
AAS Meetings: But that takes into account all the worst case scenarios and a lot of Monte Carlo simulations of possible observations. We we are very confident that we can respond within tos within 120 min 80 of the time.
AAS Meetings: So i'm going to start off with the capabilities of the X-ray telescope so we have an excellent psi phone access 2 and a half our seconds growing gracefully, which I will explain to 8 arc seconds at the edge of the field of view.
AAS Meetings: Large field of view, one square degree actually slightly larger than that. and a large effective area at around 1,700 square centimeters at one kilowatt.
AAS Meetings: Relatively, we have to be in low Earth orbit for various reasons, but our low Earth orbit is chosen to have relatively low particle background 600 kilometers, 5 degree inclination.
AAS Meetings: So i'm going to use the cursor here so that online people can see starting with the effective area plot on the left
AAS Meetings: black in each of these figures shows Star X. So this is effective areas of function of energy.
AAS Meetings: Our focal length is 4 meters. So we are relatively short focal length we are optimized for soft X-ray performance.
AAS Meetings: So you can see that it's soft X-rays we're extremely competitive. E razida is a bit higher than us but we beat all the other operating missions. since we are short focal length. We do not have as much collecting areas higher in at high energies, but we do have some.
AAS Meetings: What is very interesting, though, is our angular resolution as a function of off-axis angle in the center diagram.
So here you can see Chandra Asis, which, of course, is the best when it comes to angular resolution.
AAS Meetings: However, Chandra Asis is best on access within a few minutes, and once you get well past 5 min off access.
AAS Meetings: Star X actually starts to win because we have a much flatter, more gracefully degrading Psf. Over the field of view. So we've optimized our performance to have that good Psf. Over the whole field of view.
AAS Meetings: When you combine these things, the collecting area, the good Psf. Are relatively low background. You get this figure of merit, which is the signal noise per point source integrated over the field of view.
AAS Meetings: And this is where this is. We call this point source discovery, speed, and I know Neil Brant will be showing this in his talk. We are actually better than any existing extra mission in terms of quickly being able to find X-ray Point sources.
AAS Meetings: Then i'm going to speak a little bit on the ultraviolet telescope So again. This is being led by University of Colorado last Brian fleming's in the audience the lead for this.
AAS Meetings: And when one of my colleagues called this the whale plot, so you can kind of imagine that. And I like to say that galax we are in the same part of the ocean as galax in terms of performance. So this shows grasp as a function of wavelength
AAS Meetings: The field of view of the UV. Telescope is 0 point, 9 by 0 point, 9 degrees. So 0 point 8 square degrees total. and has 5 arc seconds. Psf. Over the whole field of view.
AAS Meetings: We have a requirement for 3 filters, but we have 5 spots in our filter wheel, and we are reasonably confident that we will have these 5 different ultraviolet filters. So every observation will be concurrent x-ray and ultraviolet. You always get both data sets at the same time. It's important thing to point out.
AAS Meetings: So we have 8 science objectives, and I have given full length colloquia where I go over most of these. So we're just going to touch upon them right now. But the the themes are fast furious and forming
AAS Meetings: so under fast the first light from supernovae, catching supernova shock breakouts, and then continuing to follow them up with Star X. So that'll be a self triggered target of opportunity, for Star X catches something and chooses to continue following it up.
AAS Meetings: Neutron star mergers, and again these things will be covered in Daryl haggard's Talk after me. A couple of talks after me.
AAS Meetings: Neutron star mergers will be able to capture the X-ray and ultraviolet counterparts to those
AAS Meetings: and then stellar flares and exoplanets. There was an excellent talk by Sebastian canada at the end of the last session, on how important it is to understand flaring activity around exoplanet host stars.
AAS Meetings: both for understanding whether we can keep the atmospheres around the stars, and also for understanding how prebiotic chemistry might be affected by flaring.
AAS Meetings: and then furious again, has to do with the creating black holes.
AAS Meetings: great
AAS Meetings: title, Disruption events. We're actually a lot of our 350 square degree. Medium survey is driven by catching a large sample of title disruption. Events, we'll get both the X-ray and the ultraviolet X-rays will tell us about the formation accretion disk.
AAS Meetings: The UV. Will tell us about the title, stream, and we're going to have those 2 pieces of information simultaneously which is very important.
AAS Meetings: And then the Agn reverberation. Mapping is the the other topic under that that theme which will be accomplished in our our deep survey data by getting
AAS Meetings: several UV filters and X-ray data
AAS Meetings: and then the last talk of the session by Mike Mcdonald will be on clusters and all that we're going to learn with this extremely deep. X-ray surveys about the formation of the most massive clusters in the universe.
AAS Meetings: So i'm gonna just introduce a couple more, talks a couple of more topics and then move on to the next speaker. So first of all, this is a plot showing X-ray Point source sensitivity versus area that is shown for a lot of x-ray surveys. You can see here Chander Deepfield South Chandra Cosmos stripe 82. And over here is E. Rosita for all sky sensitivity.
AAS Meetings: So our observing strategy, which will be covered in depth by Edmund hodges clock after me. One of our science leads. Observing strategy is to daily cover 13 square degrees and weekly cover 350 square degrees. To these, relatively speaking, shallow depths.
AAS Meetings: and the era here indicates that this allows us to do our transient science.
AAS Meetings: But then, at the end of our 2 year prime mission, we will go very deep. And interestingly, you can see that we get into the regime where Athena expects, Even with the 5, our second Psf. We are entering the regime of Athena surveys at the end of 2 years.
AAS Meetings: and this allows us to do this very deep studies of proto clusters at relatively high red shift, and also to do high red shift agen science, which is not even one of our driving science objectives.
So just to give you some numbers, we're going to reach 5 times 10 to the minus 16
AAS Meetings: Cgs, over 350 square degrees, which is more than 150 Chandra Cosmos fields.
and our deep survey over 13 square degrees will reach 9 times 10 to the minus 17.
AAS Meetings: And again Edmund Hodges click will be covering this in more detail. So you'll get this again. This is the breakdown of our time. We spend 63% of our time in these time domain surveys studying this 13 square degrees and 350 square degrees.
AAS Meetings: The rest of the time we're doing target of opportunity observations. Some triggered by external
AAS Meetings: triggers like the gravitational wave network, telling us that there's been a merger.
AAS Meetings: Others are self-
AAS Meetings: We also have targeted surveys for instance, to look at the low mass planet bearing stars.
AAS Meetings: So i'm not going to go through all this. But I want to emphasize that we will have already, in the first 2 years, a community program of about 1.8, Meg second or 4.4 of our time. So that means that any anyone in the community that wants to use Star X could propose
via website form to use the mission.
AAS Meetings: Okay, I think I will go ahead and
AAS Meetings: finish with this slide, which really emphasizes the need to have Star X.
So this shows across wavelength and messengers
AAS Meetings: the facilities. And of course not every facility there ever was is on this plot, but reasonably comprehensive plot, showing all the X-ray missions that are currently operating.
AAS Meetings: I like to say, in 2,025 there is not a catastrophic event where all the extra emissions, and that is the NASA Senior Review. We expect that they will be continued past that.
AAS Meetings: But the point is that we have, a relatively speaking, aging X-ray fleet.
AAS Meetings: and we do know that we have ultrasound in the ult ultraviolet but as we get into the late twenties twenties. We we will launch our launch readiness date as July 2020, eighth.
AAS Meetings: There's a need to put in something that would be a worthy successor to, Swift, for instance, an X-ray and UV capability to allow us to do time. Domain will be an excellent compliment to the very Reuben observatory
AAS Meetings: and also to the ground-based gravitational wave network. And I I can't help but mention. I put Lisa down here in the gravitational wave
AAS Meetings: area because we do have this chance of possibly overlapping with Lisa and our Square degree field of view is actually very complementary with the expected error regions that Lisa will have for some of its better better localized sources.
AAS Meetings: So we believe Star X. Fills in the gap in X-ray and UV Time Domain coverage in the late 20 twenties
AAS Meetings: and it will provide this simultaneous X-ray and UV. Observations, a complement optical, infrared, and gravitational, a facilities. And before I finish I have to mention that we have these wonderful star X stickers. I'm. Not the only one in the room that has them, I think Eric Miller and possibly Francesca has some. Okay. So if you want to star X sticker, don't be shy. We're happy to hand them to you. Okay, and i'll just end there. Thank you.
AAS Meetings: I'm interested in your 120 min.
AAS Meetings: What's driving that number. Okay. So i'm going to go ahead and so that it's actually a little bit complicated. And this is not up to date. It should say less than 120 min. Not 80 of the time.
AAS Meetings: But you can see what drives things the most and the biggest are these 2.
AAS Meetings: Say one to 90 min and one to 45 min. So basically.
AAS Meetings: if we get unlucky and we've just had a a a contact ground station contact and we the whatever it was that went boom. We just missed a contact. We could be waiting 90 min to come back around. Okay. And then the other is Earth a quotation.
AAS Meetings: So that is, we Again, we could get just unlucky. So we've done. Monte Carlo simulations can sort of see the allocation, so we'll very quickly make a decision. There's a transient, a basic transient event, alert
AAS Meetings: a a piece of code on board that is going to celebrate her down. The fact that we've had a transient event and more sophisticated, algorithm and a human in the loop will make a decision about whether it's
AAS Meetings: to start the process. But that's relatively quick compared to this other steps.
AAS Meetings: and all of your tos are done through ground station contacts. So there's no, there's no next-generation tedris usage. It's all just on ground stations. Let's see. So
AAS Meetings: there there are lots of next generation. I'm going to be a little careful. There's lots of next generation tedious ideas out there. But right now the plan is still to use something like Tedris. But we can discuss this in in more depth if you'd like, okay.
AAS Meetings: Okay, Thank you.
AAS Meetings: Hi. I'm: Curious to know. How are you able to get a much flatter? Psf. Or or the field of you? Is it a different optical design, or
AAS Meetings: I'm: Sorry. Can you repeat the question? Sorry. I'm: curious to know how you are able to get much Flatter Ps up across the field. Okay, how do we have the fighter? Psf: okay. So good question. The answer is optical design. So we could have designed the mirror to have the sharper Ps. Up on access, but there was a choice made
AAS Meetings: to to keep it, to have that performance off access. But and then the real, the other answer to your question is, why is it that good in the first place.
AAS Meetings: and that has to do with the a single crystal silicon port optics that Will Zhang Rpi is working on probably right now. Well, maybe not. It's very late at night on the eastern us, so I hope he's gone to bed. But so we have this very good X-ray mirror technology
AAS Meetings: that allows us to get this very good Psf: but it's it's really the real answer to your question is optical design, a choice that we made to to keep the the Ps. Up good over the whole field of you instead of we could have had it
AAS Meetings: really excellent in the core, but we would have had that same fish eye effect that you get with Chandra. So that was a choice. Yeah, sure.
AAS Meetings: All right. Next up we have Edmund Hodges cluck. Who is going to tell us about the observing strategy?
AAS Meetings: All right. Well, thanks. So you know, you just heard from, and the overview of what Star X wants to do, and it's capabilities after me. There's 3 talks that are really going to explicate some of the scientific measurements we're going to make.
AAS Meetings: And so right now I want to sort of bridge that gap by talking about how we use those those capabilities that Anne talked about in order to execute the the scientific measurements we want to do.
AAS Meetings: and if you take nothing else away from this talk, I want you to remember that Star X is designed to survey a large cosmic volume, to find and characterize populations of rare and brief events, and distant and faint sources, something that an already alluded to.
AAS Meetings: and
AAS Meetings: most of the the science that that we're aimed at doing is based on a you know, handful, or even just one example of of sources that were found coincidentally using observatories that weren't really designed to find them.
AAS Meetings: And that's great. But what we need next to really, do you know, advance the astrophysics is to understand the population of those sources, and to do that we need systematic surveys
AAS Meetings: and to highlight the power of systematic surveys. You know one great example is play tectonics, as shown in this image in the background, so the mid Atlantic ridge that that volcanic, or that that mountain range in the middle of the ocean. Here, you know, that
AAS Meetings: was originally found via coincidence. We adapt sounding when in the mid 1,800 when a boat went across the Atlantic from the Us. To Europe, and it was just sort of a curiosity at that point.
AAS Meetings: And then during World War Ii. They are of submarine warfare. Some of this area was more systematically surveyed, and we will realize, hey, there's a mountain range there. Well, that's pretty interesting, but it was still hard to connect to. You know what is the rest of the continents doing, and what is the rest of the ocean doing it wasn't until we had a systematic survey of the sea floor that we really came to understand that there's this whole network of underwater mountain ranges and ocean trenches, and then it just became very obvious. The plate tectonics, which up until that point was sort of considered a fringe theory.
AAS Meetings: was actually right.
AAS Meetings: So when it comes to things like neutron star mergers and kiloby, or supernova shock breakouts, or proto clusters, or to x-ray selective title disruption events I think we're at the point where they're more than a curiosity. But we haven't yet done that systematic survey. So how a star explained upon the depths.
AAS Meetings: Well for transient and variable sources. Star X. Will survey a large cosmic volume over 6 decades in time scale on the Prime Mission from 100 s to 2 years, and it does that, using synoptic X-ray and UV telescopes in order to capture as much of the the spectral evolution
AAS Meetings: of these sources as possible to to better characterize the physical nature of of a transient and variable sources, and, as you know and talked about, we also have this rapid response to a capability.
AAS Meetings: So on the left I put these ven diagrams of common attributes, of serve, of observatories that are aimed at discovering a transient sources, and so one important ingredient is to have a very sensitive telescope, because that's what allows you to go out to a large cosmic volume instantaneously. It also allows you to watch as transient fade away.
AAS Meetings: Another is a big survey, pro footprint, and especially a cadence survey, so that you're sensitive to variation. That's longer than a single epic, but shorter than you know, like a coming back every year, or something like that. And then the third pillar is rapid response to transient
AAS Meetings: and Star X combines all 3 of these in one package, and that's how we get this. The 6 decades in time scale. We're filling in missing time scales that have prevented us from detecting populations of these transients with the current missions
AAS Meetings: to detect distant and Fate sources. Star X surveys a large large cosmic volume, and it also doesn't over a large time scale. But in this case we're talking about a decades and cosmic look back time rather than in real time.
AAS Meetings: and Mike Mcdonald is going to tell us much more about the the galaxy cluster evolution story, the formation and evolution story that Star X is really aiming to to fill out with these deep surveys. But
AAS Meetings: I I just want to highlight that in order to find distant and fate sources. an observatory needs to have a large collecting area and and the field of view, so that you have an efficient survey speed.
AAS Meetings: You need to have a pretty wide survey footprint, because a lot of these sources are fairly rare, at least uncommon. And so you need to look over a large area of sky to find them. And then you need high angular resolution in order to reduce your confusion limit and to be sensitive to clustered sources, resources, and mid tofu submission.
AAS Meetings: So, and introduced very briefly a bunch of objectives, and I'm not going to go through this and excruciating detail. But I just want to highlight that, you know, for all of these objectives. There's they basically boil down to 3 types of observing modes, and 2 of them are monitoring, and one requires deep and wide exposures.
AAS Meetings: So to to see things change that you know we're there, but you want to see them very like agents do a reverberation, mapping and map out the structure of the accretion desk where stellar flares. You want to catch some measure, the floor frequency distribution to understand the impact of flares on exoplanets.
AAS Meetings: What we do is we? We monitor samples. So this is watching stuff that we already know is there, and we're just watching how it changes over time
AAS Meetings: to catch things like supernova shock breakouts, or X-ray selected title, disruption, events, or to follow up neutron star mergers that's looking at the sky and you know surveying sky and and waiting for something to happen, and finding transient events that way.
AAS Meetings: And then for the the cluster story. Science that's what we need. Targeted surveys for we need to to point at
AAS Meetings: for very long periods of time at places where we're pretty sure there is something, and just measure what's actually there. And so you know you don't have to to remember, even read all these boxes here. But
AAS Meetings: the the Star X, observing strategy, essentially boils down to either monitoring or deep and wide exposures. And the good news is that you can actually do a lot of these objectives in the exact same observations. And so we do this, using the very powerful a Time Domain survey mechanism that's at the heart of something like, say the Vera rubin, observatory
AAS Meetings: mit ctl. And and so what you, as an already explained, you know what we can do is we return to the same fields day after day, after day, or week after week after week, in order to see how the sources the brighter sources in those fields vary, and to to catch transient 250.
AAS Meetings: But we're also accumulating deep exposures while we're doing that. So at the end of the 2 Year Mission we end up with these very deep and wide surveys. So it's a very elegant way to do your observations.
AAS Meetings: and Neil is going to talk much more about the surveys and what we get out of them. But I just want to introduce the the concept of how Star X is planning to do it's Time Domain surveys by saying that they are based around 3 essential concepts. We need to probe missing time scales.
AAS Meetings: We need to pro spectral evolution to best understand the the nature of the the transient and variable sources we see, and we need to be sensitive to a large cosmic volume in order to see enough of these sources to build up populations.
AAS Meetings: So the surveys and already said, they probe multiple timescales by having a daily or weekly cadence over 2 years. So 13 square degrees every day, 350 square degrees once per week.
AAS Meetings: and having the X-ray and UV Synoptic telescopes is actually a really important part of how Star X operates! It's really central to to the mission, and that that point is made by this cartoon that I've drawn at the upper right here, and a lot of transients
AAS Meetings: can more or less be explained, as expanding, cooling fireballs. And so, as time goes on, not only do they fade an overall luminosity, but the peak band in which you see them migrates from, say, the X-rays.
AAS Meetings: or even the gamma, rays down into the ultraviolet and eventually into the optical, and by monitoring that evolution that's how we learn the most about the physics of what's going on like. For for example, the composition of the the circumstellar material following a supernova.
AAS Meetings: and the final
AAS Meetings: important piece is the volumetric sensitivity. So that is, you know how how far away, or how much volume can are we sensitive to events that we want to see? And you can see just from the the functional dependence down there at the bottom right, that the volumetric sensitivity is a strong function of both the field of view of the instrument, one square degree, and the X rays
AAS Meetings: point 9 by point 9, and the UV. And the effective area and even stronger dependence to the one and a half power.
AAS Meetings: So an already showed this plot, and Neil is going to show it again. I think i'm i'm not going to talk about too much. What Star X will do during its actual mission. What I want to to highlight here is that
AAS Meetings: because of the way that Star X is designed even after the two-year mission is complete. During the extended mission just by coincidence, star X is going to continue to build up
AAS Meetings: large populations of transients and really deep surveys, so that if you just focus on the weekly cadence survey here the medium survey over 350 square degrees
AAS Meetings: at the end of 2 years each one of those pointings has 40 kg, and that
AAS Meetings: that 40 kg, I can imagine, is not especially deep for a general observing program, and most general observing sources are not going to be as wide as one square degree, and that means that through just general observing of various sources over, you know, 10 or 15 years. Star X is actually going to do far beyond this 175 Cosmos fields, and also be quite sensitive
AAS Meetings: to to to transient for that whole time.
AAS Meetings: So i'm not going to go over this slide in any detail. But I just wanted you to see what the breakdown actually was, just sort of repeating what what an was showing. But there's there's 4 basic modes that we're operating, and there's time domain surveys. There's targeted surveys where we just need depth. There's monitoring of source populations. There's these rapid response toos, and there's this community T. O.
AAS Meetings: Where anyone can submit a a a request for time.
AAS Meetings: and we have this onboard X-ray transient detection capability it's a programmable. But currently we need about 10 counts and 100 s, which corresponds to a sensitivity of about 10 to the minus 13 and Cgs. And this is just to be sensitive to supernova Shock breakouts without a triggering on shot noise from persistent sources. It issues this transient event, alert within 5 min for worldwide follow up.
AAS Meetings: We have these rapid response tos that could either be responses from Star X triggers themselves or through other approved channels.
AAS Meetings: and already went over the how we get on target within 2 h 80 of the time. So I won't Go over that. And then with community twoos we have it again. About 4 of our time is available for anyone to request time, and we're going to get there within one to 2 days on best effort basis.
AAS Meetings: And this brings me to my my final point, which is that you should get involved. So if we're selected, then Star X will hold annual workshops and provide opportunities to the community to participate in our survey, planning
AAS Meetings: and
AAS Meetings: survey data accumulated over these 2 years is going to be made available as soon as possible. It the way that we work, because we, you know, Go back to these fields every day or every week. We build up these surveys over 2 years. There's not an opportunity for the team to hoard all that data and get all the best stuff out, and then, you know, release it. So we're not even going to try like this is a public mission. We want people to be engaged. We're going to give to release software and and other tools that are going to help people extract as much data
AAS Meetings: and and the results as possible, even as we're accumulating. And again, you know that we have this opportunity to propose tos during the the Prime Mission.
AAS Meetings: So I just want to leave you once again with the takeaway message, if you remember nothing else. From this talk Star X is designed to survey a large cosmic volume to find and characterize populations of rare and brief events, and distant and faint sources. And you can think of it as kind of like a Ls: T. Operating in space. Thank you.
AAS Meetings: Alright. Thank you. Admin: we have time for one or maybe 2 questions. Yeah. So I have 2 questions
AAS Meetings: for this daily Cadence Survey, where you want to study shock, breakout.
AAS Meetings: The shock breakout signal itself is less than 30 min on the on time scale minutes. So how Will you study such a brief phenomenon with the daily cadence?
AAS Meetings: Okay, I'm: Sorry that was, perhaps miscommunication. So
AAS Meetings: any Star X observation in North Orbit is likely to be, on average, about 30 min, and so any observation that we have anywhere on the sky, we will be sensitive to some shot breakouts, and when such a thing happens, it will be detected via the onboard X-ray transient finder there will be a down link within
AAS Meetings: 5 min, and then, if it is a good candidate chalk break out
AAS Meetings: right. It's. We identify luminosity or something, so it tells us it's a shot break candidate. Then we can get back to follow it up in UV. So the daily cadence is really so sorry. How fast can you follow it up
AAS Meetings: within 2 h?
AAS Meetings: I mean, that's that's what that that time scale is about. I mean. You will also, of course, serendipitously capture UV. Transients related to shock breakouts for larger stars, but the the the daily cadence. The point of that is to map, to do a reverberation, mapping and agn.
AAS Meetings: So
AAS Meetings: we're combining a number of different time scales and sort of cobbling together. You know we have sensitivity to things on 100 s or half an hour. We have sensitivity to things on a few hours, through rapid response follow up, and we have sensitivity to things that change on the time, scale of days, or of weeks. And then, of course, months and years
AAS Meetings: super quick other question: Are you going to be producing UV transient alerts?
AAS Meetings: No. So currently? That is not part of the the design, I mean, that's something that we could study in Phase B. But the the
AAS Meetings: the basic idea is that
AAS Meetings: because the you know, we're trying to be as economical as possible and X-ray events that the X-ray sky is simply darker.
AAS Meetings: and so it's easier to do. Thanks. Thank you.
AAS Meetings: I was wondering if you can clarify the target opportunity. Observation I thought I heard from an earlier on answer from to to Jamie that there was no autonomous trigger, but a few slides earlier
AAS Meetings: you mentioned that if a trans is identified.
AAS Meetings: It's sort of a a trigger to Star X to observe. Can you? Can you clarify a little bit more about how this actually is going to happen like
AAS Meetings: the 200 s that you mentioned earlier is not really
AAS Meetings: You need someone, perhaps the same.
What can you?
AAS Meetings: Oh, sorry thanks for the question. So the
AAS Meetings: the the automated process here is about vetting the candidates. So we, in just an alert from, say, Ligo ergo.
AAS Meetings: that alert is automatically processed in the Star X. Soc: say, okay, what's the localization? What's the odds with the neutron star merger, and like, basically give it a rating of is this something we want to follow up?
AAS Meetings: So that's the autonomous part
I see.
AAS Meetings: Thanks. A fantastic stuff, a question on the rare and brief events, and and thinking about things that will be by the very bright.
AAS Meetings: some transient. And you mentioned reverberation mapping you. You would love to have loads of photons to do that? I i'm just wondering what is what are the brightest sources that you can observe before you get into pilot issues.
AAS Meetings: That's a good question. So I mean in order to get population. So I'm. I will answer your question. But first, so just explain our our ethos in order to get a lot of populations. We really are going sort of more towards the pant, and we're in order to special as far back in cosmic volume as possible.
AAS Meetings: But we do start to pile up, but maybe like 10 to the minus 12. Something like that 3 by 10 to the minus 12.
AAS Meetings: Thanks. All right, let's thank admin again.
AAS Meetings: So next up we have a virtual talk from Daryl Haggard, and
AAS Meetings: I think that we have help
AAS Meetings: to get that set up.
AAS Meetings: and Daryl is going to be telling us about multi messenger studies with stars.
Daryl Haggard: Okay, good morning. Everyone Can somebody confirm. You can see my slides and you can hear me.
AAS Meetings: Yes, we can hear you, Daryl.
Daryl Haggard: Amazing thanks, Aaron. Okay. So I guess. Good morning from me, and good afternoon or evening to all of you. I'm calling in from France. So Daryl Haggard and I'm going to be talking a bit more about the multi messenger opportunities and fast transients that you've heard foreshadowed from Edmund and Ann.
Daryl Haggard: So i'm speaking today on behalf of the entire transient team. It's been an enormous team effort, and so a shout out to everybody who contributed to the science cases I'm describing today.
Daryl Haggard: So you've already seen this slide from Anne Star X has these 8 objectives, and I'm really going to be focused in on this sort of yellow box, the fast ones
Daryl Haggard: i'm gonna do a very brief run through of what we expect to be able to tackle for supernovae and for stellar flares and exoplanets, and i'm going to spend most of my time talking about that neutron star mergers.
Daryl Haggard: So diving right in the
Daryl Haggard: one that we've talked a little bit. Suvi's question at Edmonds talk, foreshadowed the questions about shock, breakout, and supernovae. Our science objective in this case is about 30 infant type, one Vc. Supernovae, and we're really going to be using the X-ray and UV capabilities of Starx together in order to characterize these sources. So as all of you know, supernovae are extremely important for both their energetic contributions and chemical contributions to galaxies and galaxy evolution.
Daryl Haggard: and one of the things that's not yet well understood, for many of these sort of exotic types of supernovae is the progenitor stars the pre-exclusion mass loss from those stars, and we really Don't have identifications for a large majority of supernovae. And so, understanding those progenitors will tell us a lot about how these explosions proceed, and the environments into which they explode.
Daryl Haggard: So you've heard a little bit already about X-ray shock breakouts. This is a a image here of supernova, 2,008 d, which was detected in the X Ray. It's one of the few shock breakouts that we have to hang our hats on, and of course the shock breakout can be very interesting for helping us to understand the progenitor radius which can help us classify the progenitor itself.
Daryl Haggard: and also, as Edmund mentioned, the extent of pre explosion mass loss, so we can help that can help us understand. Stellar wins stellar also, like oscillations, etc., in the in the early moments or the final moments before the explosion.
Daryl Haggard: So this is a plot here of X-ray luminosity plotted on a vertical axis versus time since the the core collapse and you can see here how these early X-ray emissions, tr traced out by Star X. Can help us distinguish between say a wolf and a red super giant class progenitor.
Daryl Haggard: So you can see here that these very early times this is in the first several hours can be traced out by Star X in the X-ray.
Daryl Haggard: looking a little bit later. So the shop breakouts are happening in those first 2 h. Now you're seeing a plot of the ultraviolet magnitude or luminosity versus that same core collapse time since core collapse.
Daryl Haggard: And you can see here that now the shock breakouts for a few of these progenitor classes can be traced also in the UV. And at later times we really have this lever arm, this incredible opportunity to tell the difference between different shock, cooling behaviors for different progenitor classes.
Daryl Haggard: And so the onboard event alerts can enable these prompt follow ups. You've heard a lot about that in the last couple of talks and help us actually trace out this entire behavior all the way from the very early times in the X-ray through to slightly later times in the ultraviolet. So Sirex is really optimized to use. It's 2 instruments together to characterize these types of supernovae.
Daryl Haggard: The other topic which i'll just touch on. Briefly, I know that you've heard a. If any of you were in his talk as Sebastian Pine. I just gave a really nice talk on this subject, but our second sort of fast transient science case that I'm going to touch on has to do with stellar flares and exoplanets.
Daryl Haggard: So here you're seeing a beautiful image of the coronal loops from our sun from NASA's Trace mission. We know that these chronal loops, these maybe magnetic reconnection or magnetically inspired events really pump a lot of x-ray emission out into the environment where exoplanets might reside.
Daryl Haggard: So the Stark's objective is to fully characterize 9 planet hosting stars once again using its combined capabilities. When the X-ray and the UV. So the X-ray emission, of course, is very important. It can heat the outer atmosphere. It can cause hydrodynamic escape so understanding the flaring activity of exoplanet hosts is one of the prime objectives of this science case
Daryl Haggard: also the the ultraviolet. The UV emission can can continue to inject heat into that upper atmosphere, pop up, puff up the exoplanet. And of course, both of these 2 different types of atmospheric impact can can change the habit of habitability of of exoplanets.
Daryl Haggard: So here you're seeing a plot of the intensity and the UV. Plotted versus the state velocity, and you can see how this can help us pull apart more eroded exoplanet atmospheres versus those that are remaining intact for a variety of different types of stellar hosts.
Daryl Haggard: So our objective here is to use Sarx to look at a several different types, classes of host stars, and to get a better sense of how these different types of high energy events on the surface of the star are impacting the exoplanets
Daryl Haggard: moving on from there. I'm going to now. Spend most of the rest of my time thinking about neutron star mergers. This is gravitational wave. Follow up in the era of ligo, cargo, and fog that burglar and congregate. So I just want to emphasize yet one more time. How important the combination of X. Ray and UV is here! Our objective. Our sort of baseline objective is to tackle or to follow up 10 binary neutrons, star mergers detected by the ground based gravitational wave network. So of course, we'd like to figure out the origin of any very early Blue or
Daryl Haggard: you via Mission, and also to to to constrain the early X-ray flux, and of course I'm now highlighting in blue. These 2 ranges and the UV and the X-ray, and you can see that these are going to probe very different types of phenomena the UV is really helping us get at those the Killer Nova. Very early times the explosion near the site of the actual impact of the 2 neutron stars or the neutrons star in the Black Hole, where the X Ray and radio, if we have it, Co: evil with Star X is really probing after glow, the slamming of any
Daryl Haggard: jet formation into the interstellar medium along an axis of the axis of the merger.
Daryl Haggard: So Star X allows us to pro both these thermal and non for thermal processes in the neutron star, merger, ejecta, and explosion itself. So, as you all have heard, i'm sure flag over to coag are making a comeback. So here we go. I'm observing run 4 is going to start in May 2,024. The run has been expanded beyond 12 months. It's now an 18 month run. This is gonna help for em follow up. This is very important for missions like Starx, because hopefully, we will find more sources during O. 4, and that will help us constrain our rates better for for the anticipated o 5 and voyager missions beyond that will be more
Daryl Haggard: co evil with the Star X
Daryl Haggard: Mission. So, Of course, Ls T. Will be online for the end of and throughout the 5 and we anticipate sirex launching in mid 2,028 is and pointed out, really overlapping with o 5 and voyager when Lagover go congrat have really reached their full design capability.
Daryl Haggard: So I want to talk just a little bit about these rates. This is a slightly confusing diagram. I'm just going to target in on a couple of the panels in a moment. But I just want to say Here this is the current sensitivity, and predicted expectations from like over to coagra, from the eggway website for anybody. Curious.
Daryl Haggard: of course these it improved sensitivity and longer longer runs will increase our rates. But the localizations are still quite challenging for electromagnetic follow up. So i'm going to focus in just on these plots here. I'm: in the top left corner. So this is a plot here. Now you're seeing cumulative detection rate versus the 90% credible area.
Daryl Haggard: The predictions that you're seeing here, for. O 304, and o 5 or 3 is the solid line of 4 is dashed. Oh, 5 is dotted. The lower panel in orange is Neutron star. Black Hole mergers. The top panel is binary neutron star mergers.
Daryl Haggard: and so the predictions for o 4 to 5 are based on oh, 102, and o 3. So, as I mentioned, any kind of detections we make in O for will improve these error bars that you're seeing in the error envelopes.
Daryl Haggard: But you can tell that in order to get substantial numbers of these sources, you're still looking at a pretty large localization region. I put a black line down here now on a 100 square degrees, so em follow up really needs to be able to accommodate these large localizations.
Daryl Haggard: We expect something like 2 to 10 neutrons or neutron star, plus neutrons to our black hole mergers, and o 4. You can see those dash lines I've put across horizontally, and in O 5, which is really the sweet spot for Star x. You can see that those numbers are improving. We're expecting tens of neutrons, star, neutron, star, and neutrons start Black Hole mergers.
Not all of these will be close enough for electromagnetic. Follow up, but many of them. We hope will. So this is really the prime Star X. Follow up regime. And you, if you are curious about exactly how those break down.
Daryl Haggard: thanks to my fishbox for putting together these these numbers. These are the 5 predicted merger rates within 10 square degrees, 20 square degrees and 100 square degrees. You can see, we're getting up into to, maybe a few dozen sources hopefully, a fraction of which will be really amenable to follow up by missions like Star X and others.
Daryl Haggard: Alright, so how are we going to do our start searches for I, and counterparts to gravitational wave sources. So I mentioned. So let's imagine that the localization region is something like 10 to 100 square degrees. Being the sweet spot for our project.
Daryl Haggard: We are planning on looking at these sources when about within 30 min, as Edmund has recently mentioned, sort of 30 min to a few hours depending on that uplink configuration, we're gonna first look for a 100 s exposures to reach down to shallower fluxes. This will get us to something like 10 to the minus 13 or per centimeter squared per second for something at an average distance of around 600 megapar 6. This would be good for something like a short gamma reverse. Viewed on access
Daryl Haggard: for any well localized sources. We will scan for early U. V. A mission as well as so things within about that 10 square degree, sweet spot, and then we'll perform long term monitoring to search for faint afterglows, using logarithmic space intervals.
Daryl Haggard: So what does that look like? So let me actually start here? So this is now a plot of X-ray flux versus time since merger, as many of you know, it depends what your off access angle viewing angle is with respect to the merger plane, how much flux we expect to see. So here you're seeing red lines tracing out, you know, when you're looking straight down the barrel of the jet right at the the plane of the orbit of the merger, and then, as you move off access, you can see that the flux is lower, so blue to green are
Daryl Haggard: larger and larger off access angles. In this plot you can see here what you would expect to to achieve with swift Xrt. In 10 s and 500 s, and what we are expecting to see with Star X sensitivity in a 100 s that's that initial follow up, and then the deeper monitoring
Daryl Haggard: for sources of of particular interest. So these are 5 kil. A second exposure is really able to prove all these different off-axis angles for neutron star mergers. Of course the UV instrument is equally important here. Now you're seeing absolute UV magnitude versus time since merger, and you can see the star X Expectations and teal colors and ground based optical.
Daryl Haggard: Our band imaging predicted in orange colors here, and you can see the difference between shock interaction models and killing over models, and just how much you know of a lever arm. Star X. Will give us at UV. Wavelengths between these 2 different types of models for the sources of interest.
Daryl Haggard: So we can really start to parse out the differences between these different types of models using the combination of this X-ray instrument and the UV instrument on Star x. So starch will truly be a transient machine. I think this mission is extraordinarily exciting, and I really want to emphasize that it's going to be extraordinarily important for multi messenger science. So here, now, I've just sort of highlighted the the region of time where Starx will be active, and it's overlap once again as and pointed out with Legovergo co burergo-cagra o 5 and into the voyager era, and also potentially with lisa
Daryl Haggard: I haven't mentioned neutrinos, but everybody is convinced that neutrinos are going to be an important part of the energy budget, too, and so i'll just point out here that we also anticipate being online at the same time as the second generation Ice Cube experiment. And so this opens up a new opportunity for also joint neutrino detection which the the Ligo Virgo Cocker teams are very interested in, I think, will be a very, very exciting potential discovery space for Star X as well.
Daryl Haggard: So you've already heard that there's the poster session. Please don't neglect to go and visit those posters to learn more. I'll particularly point out Mehoko ukita's poster that is covering this fast science case for fast transients, and also Sebastian Pinnato's po poster, which is diving in a little bit more to the exoplanet star interaction science, and I will leave it at that. Thank you.
AAS Meetings: Thank you, Carol. Any questions for Daryl.
AAS Meetings: Yeah. Hi, Daryl. Certainly quite a very nice presentation. I was just curious about how many supernovae shop break. I actually expect to get over the Prime Mission.
Daryl Haggard: So the our baseline is to try to detect. At least let me see. Let me go back. Sorry Who? Everybody look away for a second. At least 30 of these infant type, one BC. Supernovae for shock breakouts. As you've heard, these are very rare events. The rates are less certain, so not in every case will we be able to see the shock breakout, but at least a fraction of these 30 sources we hope to be able to capture that early shock breakout. Of course it depends whether we're
Daryl Haggard: You know exactly how that observation is triggered. This is really only likely to be possible for ones that are in the field of view of our survey of our sort of regular survey operations. So so tens of shop breakouts if we're very lucky, I think.
AAS Meetings: and and how far I would that go to what distance
Daryl Haggard: that I don't know the answer to. I'm not sure if anybody in the audience there knows how
Daryl Haggard: equal, how distant these can be
AAS Meetings: that I don't know the answer, Nick, but I could follow it with you. I I will try to answer. So we're sensitive to shock breakouts in the Xrt. That is, things that can actually be detected in real time
AAS Meetings: out to about a red shift and point 3, 5 to point 4,
AAS Meetings: and in that space, if you just use the medal that can send star information rate and the co-moving volume, and the supernova rate that we have served locally.
AAS Meetings: You expect about 74 chalk breakouts, but you know not all of them are going to be
AAS Meetings: X-ray prior to be followed up immediately, but at the at the typical brightness Well, we don't know typical brightness, right? But at at the brightness of Sn 2,080, you know, you're probably getting close to 102 years.
Okay.
AAS Meetings: Yeah, thanks.
AAS Meetings: All right, Thank you, Daryl. You have a good rest of your day. We're gonna move on to
AAS Meetings: next up. We have a Neil branch who is going to tell us about the surveys
AAS Meetings: great thanks. So, yeah. I've been asked today to address the X-ray and Ub Surveys design for Star X. You know specifically how these surveys will be executed so as to allow both the exciting time domain, science that we've just heard about as well as all the the co-added static science, and in a nutshell, as we already heard from Edwin, the the answer is that the star X surveys are kind of an X Ray UV. Version of the Ls. T.
AAS Meetings: Another project that i'm a big fan of, and you know.
AAS Meetings: admittedly, we will be working on a somewhat smaller solid angle that then Reuben does. But we can do enough to do a a huge amount of extremely exciting science.
AAS Meetings: And so with this basic approach, as we've heard. The deep and medium surveys are built up episodically via large numbers of short observations. And you know, like Reuben, you know, that that approach is only really possible if you have an extremely powerful telescope, it the X-ray telescope as well as also very powerful ultraviolet telescope.
AAS Meetings: and all those things of course, that have to be mounted on
AAS Meetings: a a a platform that has a good field of regard and excellent agility, which is the other critical strength of Star X. So that that plot there on the left shows the the solar, the the overall observing, keep out region for for star acts, and how that traps across the sky, and and the important point is that at any time Star X can intensively target a variety of the leading survey fields that we have across the sky. They're labeled Bear in that that diagram on the left.
AAS Meetings: and then in the diagram on the right shows, you know, over time which fields can be observed, at which times you know, and and when the gaps are, and at any given time there are a large number of superb survey fields always available to Star X that we can be targeting
AAS Meetings: Okay, and
AAS Meetings: I guess. And then, furthermore, well, then, as I mentioned, you know, the excellent spacecraft agility is what is essential for allowing all this stuff to be built up efficiently, and and that is also essential for allow essential for allowing the multi-mission coordination so I want to get on to the surveys design, as we've already seen this pice our part several times, so I won't, belabor it. But I do want to highlight. We are spending a lot of time on the Time Domain Survey, so they have to be designed very, very well.
AAS Meetings: So we have designed. We have developed a a surveys design capable of achieving the mission goals in in the 2 years this serves as an existence proof that the goals can be accomplished in 2 years very similar to how we actually did things on Reuben back around 2,009 when we were going into the table Survey.
AAS Meetings: However, nothing is absolutely etched in stone, and we certainly recognize that the overall surveys landscape is surely going to change substantially between now and and the Star X launch as new facilities, some of which are shown there, you know, conduct their surveys.
AAS Meetings: and so flexibility is needed to accommodate those new developments. And so, if selected, we plan to regularly solicit community input for for example, via workshops up until the time of launch in 2,028 or so, you know, to optimize this direct surveys design.
AAS Meetings: Okay, now we were. You've already heard the essentials of our existence Proof, you know. The idea is, you have these daily and weekly surveys, and over time, you know you, you you you build up to a deep survey and a medium survey. But I just want to stress that these surveys are extraordinarily powerful. The deep survey 13 square degrees reaching that's not limit.
AAS Meetings: you know. That's like
AAS Meetings: Well, it will. It's a mega. Second Star X Survey, and that's you know that that total survey put together is like a 100 Chandra deep fields of one mega. Second, exactly what I've been dreaming for for the past 20 years, or something like that that that that's an extraordinarily powerful survey. And and you are very much, you know, accessing via seen a discovery space, you know, by Get by getting to a survey like that, and then the medium survey again 350 square degrees, reaching 5, 10 to the minus 16, you know. That's like 175 Chandra Cosmos field that's an extreme
extremely powerful survey.
AAS Meetings: Okay, Furthermore, I I want to stress that you know the the standard plan that we've been working with for our existence. Proof is to have these surveys, you know, regularly sample daily, regularly sample weekly. But we do have flexibility there, just like on Reuben. You can tweak the cadence to optimize your science. Return in in some respects, For example on Reuben for the deep drilling fields. As i'll talk about more in a little bit. People are considering what are called the cordy and cadences which are more densely sampled in some parts.
AAS Meetings: Bellows of the accordion, you know, become a progressively less dense going out, and that could be very effective, for example, at at allowing improved X-ray ultraviolet reverberation mapping for some studies. Okay, so here this table shows the expected survey source yields
AAS Meetings: Okay, both in general you know, and at high red shift, and they are very impressive. You can see the the very large numbers of sources that that we expect to be getting, and I want to especially highlight down your You're the bottom of that table. The excellent source yields for high red shift, active galaxies.
AAS Meetings: and of course, here Star X is is going to be essential, because it will provide a complete hybrid shift survey, finding the obscured systems that are very hard to find from the optical ultraviolet and other techniques. Okay. And this is extremely important, based upon that bottom plot shown here. Whereby
AAS Meetings: Whoo, then this is work done by 5 view of detail. That shows that, according to our best measurements available right now out at high Red Shift, like 60% plus of of the objects, are actually fairly heavily obscured, and so, having complete surveys over very large solid angle, is essential for having a complete measurement of the high rich of Agm population.
AAS Meetings: Furthermore.
AAS Meetings: by getting those large numbers. We will also, of course, derive reliable space densities, and the space densities right now are, you know, are not too bad up to riches of 3 to 4, but they really fall apart, getting up to ridges of 5, and beyond, as you can see, from plots like that. So you need these very large surveys, you know, to be able to nail down the space density there up there, and and to
AAS Meetings: ultimately that' be able to make reliable differences about how the first supermassive black holes grew. Do they? What what types of seeds do they come from? And and then, of course, I will also mention that the the the high ridge of the agents act as an effective tracer of proto clusters, as we'll hear from from the next speaker. Okay. So
AAS Meetings: the of course, to be able to do all this follow up on all the all this, all these high, richest ages. You're going to be deep optical infrared data that's going to be critical for selecting the high-risk. If a g ends for spectroscopic follow up. And so that brings us to this issue of sighting of the surveys and synergy with other survey facilities. So with suitable siding star racks can work with Reuben Euclid, Roman Spa, and so on. To have well contemporaneous coverage
AAS Meetings: for opt for the optimal time domain, science, and also the deepest possible supporting multi wavelength data to allow efficient and highly effective follow up, and I want to talk about that now. So our our current thinking is that the deep survey, for example, could be quite straightforwardly cited in the prime
AAS Meetings: a somewhat more than 20, about 22% of the 60 square degrees Plan for the Lsd drilling Fields. And so what you're seeing in this plot is an operation simulation that the Ls. T. Folks the Reuben folks have run.
AAS Meetings: and Reuben has chosen right now 5 fields that it's going to observe much more intensively than it's General 18,000 square to reserving their Cosmos Xmlss Chandra deep field south of Ys, one in the Euclidean field south. They're They're all listed there. Okay.
AAS Meetings: And the key advantage of Star X. Also observing these fields is well. Of course you'll have unmatched multi wavelength, imaging and spectra. I'll say more about that in in the next couple of slides. You will also, of course, have contemporaneous Ls. T. Coverage in Ug. R. I. Z. Y.
AAS Meetings: Okay, and you'll have also good complementarity with Euclid and Roman, as I will talk about further. This table here shows the locations of those the drilling fields and these deep drilling fields. We already have been gotten to work on them, you know, gathering multi wavelength data getting ready for Reuben. And there are certain regions of these fields. Reuben, of course, has a 10 square degree fuel to view. There are certain sub regions of that 10 square degrees that that is better.
AAS Meetings: and I've listed them there as as the prime multi wavelength solid angle for Cosmos. Well, there's there's the famous 2 square degrees, and then, as you can see for a Y. Ss: one xmlss and the wide region of the tragedy field south. We now have several square degree coverage. Okay, that's that's quite high quality. Here, for example, there's the coverage
AAS Meetings: that we have now from the for the for the
AAS Meetings: A wide region around the chandity field, South Xml. Newton is now get got a paid super panoramic X-ray imaging all around the the old for deep Chandra region and there's superb multi wavelength coverage that has listed in that table spanning the electromagnetic spectrum.
AAS Meetings: Okay, so there's there's a per data there already available. And similarly, if you add up all the areas that we have the prime multi wavelength areas total, somewhat more than 15 square degrees already, and so are easily sufficient to accommodate our 13 square degrees Star X Survey. Okay, I also just want to highlight the relative field sizes. Okay, this plot here is a simple one, but it is is quite important. You can see here. This compares the the fields of view of Ruben, Star, X. And and Roman. The star X feel comfortably fits inside of a Ruben deep drilling field.
AAS Meetings: and 2 to 4. Star X fields can very effectively cover the prime multi wavelength areas in the Ruben deep drilling field. So it just fits together very very well.
AAS Meetings: And then, of course, there are also plans to observe the Reuben deep really fields, for example, with Roman, I've I've I've involved in a proposal that just went in, you know, I guess last week or the week before it all becomes a blur. There's so many proposals, but
AAS Meetings: but but just very recently there's been a very large Roman program put together to target parts of the deep drilling fields as well. And so you know, you could imagine that every time Roman is observing in the deep drilling field. Star has to go. Co. Observe with it to do excellent transient science, as well as excellent multi wavelength science all in one shot.
AAS Meetings: I'll also just highlight that there are. There's a a a huge amount of additional multi wavelength data coming in for the deep drilling fields. It it it's listed here the By the time starx launches we should have superb spectroscopic coverage from all those spectroscopic surveys in the top panel as well as a loss of superb photometric coverage.
AAS Meetings: I'm almost done here. I also just want to say a few words in about the sighting of the medium survey. Okay. We also have excellent plans for the Medium Survey excellent options. There, again, there it's harder. You have to get 350 square degrees of good coverage. Okay, but but you can actually probably do it pretty well.
AAS Meetings: We have about. We have the remaining 47 square degrees of the Lsd drilling field, we could hit all the rest of it. Okay, for you know, for part of the medium survey, you could also do the Euclidean field north, which is about 20 square degrees. You could do stripe 82. You could do parts of e fans you could do and n ao deepwide fuel survey booties. You could do the Roman supernova field hyper-doop hypers, prime can service, and so on. There there there are many super possibilities there to go after.
AAS Meetings: And then, as i've mentioned, admin has done a lot of work on operation simulation, and show that that that that that the deep and medium surveys can be executed for the real seals that are up there on the sky in the 2 years.
AAS Meetings: you know, along with all the other proposed observations that have been discussed today. So we could actually execute this. We have an existence proof. It could be done. Okay. And then, just to wrap up here, as has already been mentioned, we AIM to deliver actually an ultraviolet enhanced data products, including surveys for catalogue, promptly to the whole community. This is a project for everybody, not just for the the team members
AAS Meetings: mit Ctl. And okay, we reasonably, you know, expect that Star Wats will operate for much longer than its two-year requirement, and that will allow many additional, extremely powerful X-ray and Ub Surveys projects driven by community ideas, 150.
AAS Meetings: And so I would just ask to you know that everyone will, you know, if we are chosen, what will help us make this direct surveys a great success, and i'll stop there. Thank you.
AAS Meetings: Thank you.
AAS Meetings: Questions for Neil.
AAS Meetings: Hi! I had a question about the UV. Observing strategy. I saw there are 5 UV filters. Will there be a default way in which you cycle through the filters, or do you
AAS Meetings: expect to use one usually unless there's a special case? Yeah, okay. So yeah, I I kind of jumped through that I was going pretty fast, I guess. So. So there are.
AAS Meetings: Thank you. Yeah. Okay. So yeah. So so
AAS Meetings: I have listed there. The Ub. Gaps to start with. Okay, at 180 nanometers. So that that gives you an idea of the depth we get daily, weekly and then for the deep and the medium. The medium still doesn't quite hit confusion. The deep hits confusion. Okay. But then, in terms of how you cycle through the filters. Yeah, the the nominal plan does Have you know, a balancing between filters? What what do you cycle? What's made up in 2 or 3 filters? I haven't written down an email from Admin.
AAS Meetings: What is it? 2 or 3 filters you? You've balanced it out, and that's why the numbers that up the way they do. So for the the deep survey. As I said before, the goal is ag and reverberation mapping, so we do do 1,500 s per pointing and 700 s in each of the 2. The UV filters listed there 180 and 275
AAS Meetings: for the medium survey. We basically switch every other week. So you have one week and 180 the next week, and 275 back to 180,
AAS Meetings: and then the the third filter that we're requiring is that 225, and that filter is a a strongly red suppressed filter, comparable to uvm 2 on board Swift, and the the point of that is to be able to observe red sources like low mass stars.
AAS Meetings: to measure the stellar flares. But for the surveys. That's 180 and 275 Great, Thank you. And then let me just again add I mean i'm. I suspect you have various ideas in mind, I think just what some of the might be. But you know again, like I said, we, we we do.
AAS Meetings: It went away. Okay? Well, we we do plan to, you know, take community input there, and so we can tweak those. You know that those filter balances to get to get the optimal science. If we miss something you think is really important. We're certainly happy to take that in mind.
AAS Meetings: Great, Thank you. All right. We're gonna have to move on. Thank you, Neil.
AAS Meetings: and I think we have the people on Zoom could not see your slides, Neil.
AAS Meetings: but so I think we need a few minutes to. We'll make sure. I just want to point out that all of our presentations will be going up on our our website and this session. All the sessions here are being recorded, so anybody who registered will have access to the recording, I think, on them within a matter of days, and then the rest of the community will get access within a month.
AAS Meetings: so all the slides will be available on our website.
AAS Meetings: Are Are we good? Yes, we are ready to go. Okay.
AAS Meetings: Last, but not least is Mike Mcdonald, who is going to tell us about those integrated deep surveys and talk about
AAS Meetings: clusters of galaxies
AAS Meetings: just waiting for it to load up here. Not good.
AAS Meetings: Okay. I'm keenly aware that I stand between you and dinner, so i'll try to stay on topic here. So i'm going to talk a little bit about the galaxy cluster work. We're going to do with Starx, and we have yet to have a galaxy cluster session at this head meeting, so i'll just give you a little bit of background. So at at low redshift in the local universe, galaxy clusters are very similar
AAS Meetings: to one another, and there's a lot of universal traits, you know. Every cluster has a giant elliptical at its center, more or less. Every one of those giant ellipticals is radio, loud and red.
AAS Meetings: all the satellite galaxies of the same age. The intro cluster plasma is all the same metal medallicity cluster to cluster. It's a third solar medallicity, and every cluster we look at it's always the same gas fraction. It always has the same pressure, profile entropy, profile temperature, profile. There's all these sort of universalities
AAS Meetings: in clusters on on large scales.
AAS Meetings: and we don't really know, you know, when all of these universalities were set up. And so the you know we we don't know when really the inter cluster medium was established, you know, when it was heated, when it was enriched with metals
AAS Meetings: when it first relaxed in the potential. When Agn Feedback turned on and started heating the gas. When the central galaxy assembled. We don't really know many of these when in terms of galaxy, cluster formation and evolution. And that's because we've been limited in terms of our samples. Largely
AAS Meetings: so. This is a plot i'm going to spend basically the rest of the talk on this plot. And so i'll I'll introduce it. This is mass, you know. Roughly, the viral mass of of a cluster as a function of red shift. And I've just labeled, you know, 2 highly successful surveys here
AAS Meetings: the roast that all sky survey, and blue. These are clusters, bronze from from the All Sky Survey, and the simple telescope cluster, survey, and black. So the roadside all sky survey is a flux limited survey, so it's really good at detecting things. A wide range of masses at low redshift.
AAS Meetings: and the millimeter wave surveys that use the Sunday of so, though, which effect select massive clusters at all red shifts. And so you get sort of this hockey stick distribution of of systems.
AAS Meetings: So you know if we look at where the the Perseus cluster lies on this plot, so the person's cluster is kind of the most well-studied cluster in the universe. You know it's around 6 times 10 to the 14 solar masses at Redshift 0. And this is the evolutionary track that we expect for the Perseus cluster.
AAS Meetings: And so, you see, you see, with the the samples we have available, we can track the evolution of the Percy's cluster, maybe out to redshift a half. You know we can see the progenitors at first, they said to about redshift the half with these these samples.
AAS Meetings: and so we'd really like to be able to to sort of fill out this space. You can kind of guess how I've designed my axes here, and the white space that i'm going to fill all this in in the next few slides
AAS Meetings: be awfully sad if I didn't. Okay. So so this is what's you know, coming or or already on us here. So E. Rosita, and are happening, and they're building their cluster samples right now. And so these are. These are sensitivity curves. So we detect clusters above these lines for each of these surveys
AAS Meetings: the next generation surveys. You know Athena will have a a. W. 5 survey. See me at the stage. 4 Cmb experiments we'll, we'll detect clusters at even lower masses. So this is sort of the landscape with sort of present day, approved ish instrumentation.
AAS Meetings: and then i'll just you know, put up what what Star X is gonna do for us. So there's sort of 3 starx surveys that that affect sort of cluster stuff. So the medium survey, which is very wide and shallow. The targeted survey where we target the 20 most massive clusters known in 2,028
AAS Meetings: as the centers of our our pointings, and then the deep field, you know, which Michelle just talked about, which is 13 square degrees, and Meg a second over the whole region. so we can, you know, convolve these sensitivity curves with with simulations, and ask you, what do the actual populations look like? And that's shown right here, so I've shown sort of an I I've shown an obnoxious color scheme here, there's, you know, red and lighter red and orange sh red, or the 3 different surveys.
AAS Meetings: and so the the darkest red is the medium survey, you know. You could just see, as you go deeper you detect clusters at lower mass and the take away here is that there's, you know, thousands of clusters on this plot.
AAS Meetings: and they span, you know, out to you know who knows when you know clusters turn on, and the X-ray. But if they're still, you know x-ray by it or and shift, for you know we might see a couple.
AAS Meetings: So this is showing us, you know things will detect, but detecting something isn't usually, you know, sufficient to do to do science, and so, just as an example. In the upper left is the bullet cluster. This is like one of the most massive clusters in the universe at Red Shift, like Point 3,
AAS Meetings: and it's, you know. Beautiful right? It's got this shock front, really, you know, neat morphology.
AAS Meetings: and in the lower part there is what the bullet cluster looks like at 200 counts, which is our sort of detection threshold. And it, you know, is is not nearly as as beautiful, and so it's. You know you don't, you can't tell. It's a major merger, for example.
AAS Meetings: and so we can say, you know how many systems will start. See that suitable depth to do you know, cool science, right? And so that's maybe something like this plot where we've now shown just the the clusters for which we can make You know spectroscopic measurements measure things like a temperature, a metallicity, a morphology, you know, dynamical state of the cluster.
AAS Meetings: And so now this little thumbnail at the bottom is, is what the bullet cluster looks like at 2,000 counts, and you're starting to see that it's, you know it looks like a major merger, you know there's the the the bullet component on the right and the main cluster on the left.
AAS Meetings: And so we're gonna have, you know, hundreds of clusters above red shift one at this depth deep enough to to measure metallicities and and temperatures and and morphologies. The the current archive, you know, has the border. 20 clusters of this depth.
AAS Meetings: The the Chandra archive. We'll also have of order 20 clusters at this depth above rich, if 2, which you know, we currently have 0 of those in the archive. and then we can, you know, keep pushing this. We can ask you how many clusters will start, See at 10,000 counts per cluster, and that's when you start to the bullet Cluster starts to look like the bullet cluster, and you can do things like
AAS Meetings: measure shocks, you know measure, you know, morphological, you know curiosities like bubbles and and sloshing, and you can make resolved temperature measurements and resolved metal to see measurements. And so there's much fewer of these. But there's you know, 25 clusters between Red Shift one and 2 where we'll be able to to to detect that this level. And you know we have 0 such measurements right now, and none really in the pipeline.
AAS Meetings: And so we're really gonna have. You know, a much, You know, a variety of different depths, and a you know, a huge sample of clusters to work with.
AAS Meetings: So let me show you what a couple of clusters may look like. So I've just drawn 2 black or 2 purple squares here. This is 2 clusters at rich of 2.8, and this is how Star X. Would see them. So on the left our illustrous simulations. These are gas maps of clusters at a mass of 3 and a half
AAS Meetings: times 10 to the 14 solar masses, and one times 10 to the 14 solar masses. And then, if we put chander on these clusters for a mega second, you see a really nice background map, and you know essentially no cluster emission.
AAS Meetings: And on the right is what we'll see with Star X right? And so for the more massive cluster. Obviously, we we get more counts, you know. There's enough counts there to make, you know at least one measurement of the medallicity and temperature of the gas, maybe 2, we can, you know, make a morphological measurement. The lower mass cluster is lower signal to noise, but we can see that it's dynamically active, right? It's not spherical. It's elongated.
AAS Meetings: you know it's it's undergoing, You know, some pretty major accretion there. So this is, you know, the type of of data we expect to see with Star X for red to 3 ish clusters.
AAS Meetings: And so the the science that i'm sort of most interested in in doing with Star X, or at least what I, you know wrote in the proposal was, you know, understanding the the metal enrichment of the diffuse universe. And so this is something that that
AAS Meetings: you know we've been doing as best we can with with a simple telescope and Chandra, and so on. The left here is is in in red are really deep observations of register 0 clusters, you know. They're all a third solar medallistity in the hot, diffuse plasma in this kind of
AAS Meetings: sickly, brownish color is, you know, observations I made with, and the other Spt folks, you know, 100 clusters that redshift, you know, a half to one. And then, you know, Anthony Flores has done some sort of remarkable work at at Redshift one and a half, measuring the metallicity in clusters using Xml. Newton
AAS Meetings: Starx will extend this from our shift one and a half to rich of 3, with, you know, hundreds of of new cluster observations.
AAS Meetings: and it's really between red shift, one and a half and 3, where it we expect to see evolution if it's if it's the you know, Starbucks driven wins that wretched 2 and a half that are are filling the universe with metals. Then we don't really expect to see much metal evolution until we get it to those red shifts.
AAS Meetings: I'm not gonna talk too much about this, because there's 2 great posters on this. But you know one of the things we'd really like to do is is study. You know where the the cluster meets the cosmic web. Alexi Vicklin, and, you know, had a a really a large program a few years back to map out a bell 133, you know, past the Bureau radius
AAS Meetings: and and you know after a lot a lot of work detected cl filaments feeding this cluster. And so this is, you know the best, you know. Observation it to date of of where the cluster meets the the cosmic Web and Starx will do this in, you know, single pointing right? And so we'll do you know, I've order a dozen clusters to similar depth
AAS Meetings: where we're seeing the filaments feeding the cluster without having to do. You know a lot of mapping like we had to do with Chandra? It's just you know single pointing per cluster, and so that we're really taking advantage of the the large field.
AAS Meetings: So there's a lot of really cool stuff, you know. We can do with these, you know, stacked deep surveys. The the overall theme, you know, from the cluster side is to just, you know.
AAS Meetings: follow the the growth of the most massive structures in the universe. And that starts at the very beginning, when clusters sort of begin separating from the cosmic web. You know, we hope, maybe with stacking on proto clusters, we'll be able to detect the the turning on of the proto- icm, You know we'll be able to see triggering of agen in the proto cluster environment around redshift 2 to 3, where the clusters are really sort of collapsing into the their potentials. We'll see the first enrichment of the hot gas. We'll see the relaxation of clusters at early times.
AAS Meetings: and then at late times They're still growing right. We're gonna see the the continued growth from cosmic filaments and and the creation on large scales. And you know, understand how that gas is coming in to clusters, so i'll stop there and take questions.
AAS Meetings: Thank you. Any questions for Mike.
AAS Meetings: Please go to Mike. Yeah.
AAS Meetings: Hi, Mike. Very interesting talk. I'm actually wondering so obviously about metallicities.
AAS Meetings: Would you also be able to look at at different metallicities in the core versus the outskirts. If you take a rich it, you know 2 or 3, or even 4 clusters, or what would you be only limited to to sort of integrated with the ICT measurements?
AAS Meetings: Are you asking if we'll have the angular resolution to separate core from outskirts.
AAS Meetings: Yeah. Short answer is yes. So the the Psf will be, you know, of order.
AAS Meetings: You know I guess like
AAS Meetings: 25 kilo par 6, 30 kil a par 6 if i'm doing that right. And so, you know, if the core is of order, 50 to 100 kilo, par 6,
AAS Meetings: yeah, we'll get, you know, several.
AAS Meetings: Yeah.
AAS Meetings: Thanks. Yup.
AAS Meetings: I'm: like, yeah, it's it's a related question. But as in the context of thinking, this is fantastic. But when we're talking about the survey fields, and and you're dealing with the the the worst. Psf. Over over a significant fraction.
AAS Meetings: I, by the time we're getting up to 6 or 8 s. Psf: that's 50 kilo par 6 or so. So i'm. I'm wondering in a situation where we expect to have
AAS Meetings: a significant number of agn inside these clusters. Are we really able
AAS Meetings: to to pull those things apart
AAS Meetings: once the Psf. Gets that? That?
AAS Meetings: Yeah. So so I've sort of 2 answers to that. So so answer one is, I guess.
AAS Meetings: Let me go to this slide first. So in in the case where we have 2 and a half our second Psf. You know we feel pretty confident we can separate the diffuse submission from the the agen. You know that won't always be true. We'll get host a couple of times by just really unfortunate placement of Agn.
AAS Meetings: But you know there's there's 4 agn in this cluster, and we can, you know, separate those out. Most of the field of view will be worse than 2 and a half arc seconds. But if if we look at you know the slide here. You know, this tiny font in this tiny purple circle
AAS Meetings: 20 square degrees will be centered on redshift 2 and a half clusters, and so we'll be using the optimal Psf
AAS Meetings: for at least
AAS Meetings: 20 ish red shift, 2 to 2 and a half clusters, and so that's you know the the metallicity evolution constraints are mostly driven by by those, you know, really really nice clusters at at the highest spreadsheet.
AAS Meetings: All right, thank you, Mike.
AAS Meetings: So that's all we have for tonight, and thank you for all of the good questions, and wish us good luck in our step, too, alright, thanks. Everyone.