08:05:03 All right. Hello everyone.
08:05:05 Oh here comes the official count down from Jes.
08:05:10 Thank you for all attending Week Four of fundamentals of gashes halos.
08:05:18 And I think we are down with this routine but there might be some new people this week has our topic shifts to our own Halo.
08:05:27 So, I have a our standard introductory slide here, where we talk about zoom and how we run this program, and we encourage people to meet yourself and not speaking of course and I think people are very good at that.
08:05:47 And we actually are great in zoom such as raising your hand.
08:05:53 You can always change your display name.
08:05:57 And I haven't yet because I'm still named Cameron homos.
08:06:03 And, but you can do this every time and add your pronouns, as well. And a lot of people use chat window and zoom in Sunday, and that's okay.
08:06:12 But it's also important to also use the associated KTP Slack channel, and this week the Slack channel is Halo 21 week for our galaxy.
08:06:27 And for questions and comments related to the presentations.
08:06:33 And, of course, these are being recorded the presentations, especially on Tuesday and Thursday, and the tutorial is on Wednesday, Mondays and Fridays, especially the speak collaboration, and the collaborative discussions are not recorded.
08:06:48 Those are more open ended where you can feel free to say what's really on your mind.
08:06:57 All right, here we go.
08:06:59 So this week is the Milky Way Halo week, what does the Milky Way tell us about gashes halos.
08:07:07 And I am very excited about this week because there are Halo is very complex and we're learning a lot of new things about it from recent observations.
08:07:25 So what last week was very is pretty intense I was theory theoretically oriented, a lot of really nice idealized simulations, beautiful simulations. This week I think we'll have a combination of a lot of observations, spanning many multi wavelength from
08:07:38 the heart to the core to everything in between.
08:07:43 and. I think we've had some really recent amazing results about the Milky Way. We will learn this week, both from the gashes perspective but also, you know, something that I have been kind of following with a lot of interest is some of these guy results,
08:07:59 and the chemical taking of stars in our Halo, as well, telling us about the history of the microwave Milky Way in a new way, and how our merger history might likely determines the status of our galaxy of our Halo.
08:08:17 So I'm looking forward to having a, you know, interdisciplinary discussion of that of all the methods that we're focusing on in this program.
08:08:29 Of course, we encourage you to take the survey still the week three survey is up and if you fill that out by the end, you know midday today.
08:08:41 The organizers, we will synthesize these results, already we got about, you know, 30 responses and every week survey is different. They're targeted, they really take only a couple minutes, and if you want to fill out more we encourage you to do that but
08:08:58 you can get through it in one or two minutes, and the link for it is in Halo 21 General slack.
08:09:07 So, and already, we've integrated some a little bit of bad advice, into this week from last week's survey that was put out on Friday.
08:09:18 Okay.
08:09:20 So we had something new. Last week we had, I hope every I forgot to ask. I hope everyone had a relaxing weekend.
08:09:29 I kind of didn't it was kind of intense weekend.
08:09:32 but we had a really fun time on Friday night, we have this entertainment budget from thanks to KTP, and we used to, you know, a great effect on Friday night with jet city trivia, and that was fun, it was about 90 minutes.
08:09:54 And there are about 2022 of us, and significant others and children were invited.
08:10:01 They all helped.
08:10:03 We have seven teams of three actually six teams of three in one team of four. And that one team of four One, the, the quiz contest in dramatic fashion in the tiebreaker which came down to the end I was having the other team.
08:10:24 And so congratulations to Cameron fiery Johnny and Zach for getting how, you know, figuring out how many miles where it was in the original route 66, I think maybe we'll do this again Jess.
08:10:38 And maybe we'll have a more international theme I don't know.
08:10:42 It'd be fine. And then we'll do some other things, maybe not this week but I think we should try to aim for another social our next week, perhaps.
08:10:54 Okay, um,
08:10:58 we have this this halo this halo 21 new, new results. YouTube channel is really, you know, building up a lot of great results and already.
08:11:11 You can see that I just took a snapshot of this and there's already a fake count up at least like about 25 videos up there and there's about eight new, new results video from week three week four.
08:11:26 And these are all four minute videos and they're very, very well done.
08:11:31 And I want to highlight this week's videos I think I got, actually it's week three, and some week for ones and they don't necessarily have to be exactly on that week's topic but often.
08:11:48 Often they are. So I want to give a shout out to Maddie Chen.
08:11:54 Aaron better at buoy the second, Dave. Dave Right Perseid Phil carrot had a dish.
08:12:06 Rational spark read data and Priyanka saying, and I've watched seven out of the eight Priyanka just put hers up last night.
08:12:14 So I definitely recommend all of them.
08:12:17 And this, I think this will be great because if is a way for everyone to be involved. And you can put up more than one. Just a reminder that it should be either something that's not published or published within the depth of last calendar calendar year.
08:12:40 year. And we also have on the fundamentals of caches halos YouTube channel, a separate playlist for researchers on the job market. And it's also cross posted in the Slack channel Halo 21 on the market, except to a 15 minute presentations, and there's
08:13:16 UV radiation from stars, some theoretical calculations on that.
08:13:21 So, highly recommended and I think that will continue to be populated There's no rush on that.
08:13:28 It will be always there and preserved on on YouTube.
08:13:33 Okay, so let's get to this week's exciting program.
08:13:40 And we have to feature conversations.
08:13:46 And the first one is Halo 21 Milky Way.
08:13:52 Our own atmosphere, by Jessica work.
08:13:57 There she is. And young Jane, and they are very well organized, hopefully more so than that, the conversation troupe. I ran a couple weeks ago, so every everything is improving and I also, it looks like smell bialy, and reality have collaborated a nice
08:14:22 presentation on the analogies and differences between the is M and CGM Halo 21 is MC GM channel.
08:14:30 So they will begin the feature conversation today and the first part of the program today, and have a short presentation up to 15 minutes each.
08:14:41 And then of course we will have speed collaboration, and I'm going to have give a note about that based on some feedback we got.
08:14:50 So, they will have actually an after party as they will talk about, at some point, or at least one of them will. And so we all hear about that in a little bit.
08:15:01 So Tuesday we have a featured talk by Mary Putman.
08:15:08 I'm very excited about that. Mary is the only person I see in person who attends this meeting.
08:15:15 More about that later. And she has a great panel that she helped select 13 of best law admin Hodges cook.
08:15:25 Chris how and Frick event for it.
08:15:29 So that will be very nice. Tomorrow I'm sure that will get a big audience.
08:15:35 Then we have Wednesday tutorials and we do have three again and we won't ever have more than three.
08:15:42 And that can be a pretty intense day, a lot going on a lot of breakout sessions afterwards.
08:15:49 A lot of discussion in the slack channels. So this week, we have Kartik Sarkar talking about the family bubbles.
08:15:59 Then Marcus Bruggen talking about the related, but newly discovered he Rosita bubbles. And then, and I like this young Jane will have like a true tutorial how to deploy MD blend the Milky Way is them from the CGM, and that is such a difficult topic, it
08:16:20 deserve its own tutorial. So, I will attend all three.
08:16:23 And then Thursday we have Filippo fracture Nelly talking in a more theoretical keynotes presentation, and we had a lot of people for this panel. It was hard to decide to we made it a larger panel.
08:16:43 A yaka ferryman reality, near Amanda car. Frank Vanden Bosch, and Jess again.
08:16:54 And of course the lipo and the main the keynote speakers on the panel as well. And that goes from the panel goes from the second hour from nine to 10am.
08:17:05 Okay, I'm going to take a drink of water here.
08:17:13 And I'm about to turn this over to our first color, ongoing our featured conversation, but a couple of tips, because I think people are pretty well. Practice it at this but we definitely encourage you to put a picture of yourself on the Slack channel
08:17:30 Practice it at this but we definitely encourage you to put a picture of yourself on the Slack channel and start to hard to do, along with other things.
08:17:41 Everything about your name, you can pronounce the pronunciation. That's helpful affiliation pronouns, etc. and it's easy to change your preferences as well.
08:17:47 Feel free to ask one of us.
08:17:49 I've haven't used that the way I have until this program. And I keep on learning things and I'm one of the organizers so it's never too late to learn.
08:18:01 Of course, we have this Slack channel channels listed and you have the channel browser.
08:18:10 And it's a long list but it's well organized and you can go in between channels and follow the ones you are interested in. And we, there's, there's our channel week for our galaxy.
08:18:22 For this week's program
08:18:27 pins pins are useful.
08:18:30 Last week, from the collaborative discussion we had.
08:18:38 Cameron post summaries of the two questions.
08:18:43 The two mentee voted questions that we decided in the end he pinned the result up on there so you can feel free to pin things that are important in the separate slack slack sub channels, as well.
08:19:00 See your static. Oh other advice, I'm, feel free to, as we have panel discussion such as on Tuesday and Thursday to use slack to, you know, ask questions to the panel.
08:19:17 After the keynote speech, and it's okay to like give thumbs up, or even thumbs down, and then that way the panel knows or other reactions to it, and that way the panel knows, you know what, what is the audience interested in whether the participants What
08:19:33 What do they want to hear about next. So, I am going to stop the share, I've gone on long enough.
08:19:42 And I am going to turn it over to Jess and yon. I believe we're going to talk about our first feature to conversation.
08:19:54 Okay, I'm going to share my screen just, yeah, good times good news if you want me to.
08:20:04 Okay, so thanks young. So we're going to start out with a little experiment, but first I guess I'll give you some context.
08:20:14 So because the Milky Way is our own galaxy.
08:20:18 We have treasure troves of data that uniquely constraint, its properties but also as will hear from young.
08:20:26 We because it's our own galaxy. It makes it much more complicated to study.
08:20:31 My PhD thesis advisor Mary Putman and used to say, We're like a meatball in a plate of spaghetti. And I really love that analogy, it makes me happy.
08:20:42 Okay so, but the thread that kind of unites, a lot of the topics we wish to discuss in our channel Halo 21 Milky Way. Ultimately kind of comes back to this age old question is the Milky Way actually an all star galaxy, not only in terms of its stellar
08:20:58 content, the content of its gashes disk, but also in terms of its caches atmosphere, um, you know I think ultimately we're seeking to understand the Milky Way and the broader context of the universe so this question kind of drives to the heart of the
08:21:11 matter, and and links, a lot of the individual questions that young will introduce in a minute. So, I'm just quick quickly the answer to this question is almost certainly Yes, in some ways, no and others depends on what you mean.
08:21:28 There's lots of gray area lots of nuance. That's what we will discuss this week will live in the gray area, we love nuance right but for right now, I want you to go to mentor, calm, and those of you who've been to the Friday discussions know exactly how
08:21:42 do this okay just go to nd calm, easy MEMTI calm, enter code 1625 070 is important there, too. Okay, that gets you to the vote, and I want to know where you all stand right now, at this moment before we begin our nuanced discussion.
08:22:02 And if you think it's more Yes, and I'll start galaxy the no vote yes, if you think it's more not announced our galaxy vote no. And if you really have zero opinion whatsoever, which is hard for me to imagine just abstain and let me know that you're present,
08:22:17 you're alive.
08:22:20 You know you're, you're here thinking, and I am just going to, you know, sit here for 30 seconds well you all think about it and vote and I'm going to tell you the answer right now in real time this is the amazing thing about Monday I'm just watching
08:22:33 the votes come in, 27 people have voted. This is really interesting right now because I totally disagree with this vote.
08:22:53 So, hopefully, you know this week maybe that will change your mind. So, But,
08:22:52 Ben thanks for that and else our galaxy and a typical LCR galaxy are different in my book that's really interesting. All right. Maybe we'll talk about that later to my answer would be different to those two questions but
08:23:08 there is a lot of gray area mark, it's absolutely true. So I've seen 5253 votes. votes are still coming in. So just hang tight for a second but I see the way this is going clearly.
08:23:22 Six.
08:23:25 All right, 20 seconds to vote.
08:23:28 It's not hard monday.com enter that code you can do it on your phone even Monday, calm is super easy for real time polls, we're using it in the Friday discussions, this is a little different, watching, watching your votes come in.
08:23:59 10, nine, eight, really, you know, there's 96 of you here, and only 6061 of you have voted. Come on.
08:23:58 How much is meant to be paying you. You know what, good point Drummond zero dollars right now but you never know.
08:24:07 All right, well 61 of you voted Oh, 62. Some of you are truly abstaining which I find very interesting you know this is totally anonymous nobody's gonna make fun of you.
08:24:17 You know, for your for your answer nobody's going to know, I just want to get a baseline of where we are, where, where are we starting from with this group.
08:24:27 All right, I'm going to stop stop the voting.
08:24:30 Alright so are you ready drumroll with 65 votes in, we have 37 four Yes, the Milky Way is mostly a typical 00 L star galaxy. 37 out of 65. That's more than half of you.
08:24:53 Only 18 say no or mostly probably not right, 18 say 18, say no and 10, have you decided to totally Epstein, you have a fully open mind, you're ready to learn this week.
08:25:01 Alright, well that was a really interesting experiment, let's carry on. So, we realize our, our channel name is a little broad, right, and there are a lot of other channels that are going to overlap with some of the topics that will cover, and this is
08:25:19 a non comprehensive list of some of the other Halo 21 channels that are certainly relevant to to this week's discussion.
08:25:31 And we're not, you know, trying to be exclusive will try to not focus on some of the other things this channel focused on like the interface or, or x ray observations of the Milky Way Halo but what we really want to do with our channel is unite a number
08:25:44 of, you know, observers that use totally different methods from pulse artist version measure to X ray admission to UV absorption and studying the Milky Way Halo specifically I just love this idea of uniting our communities in service of truly trying to
08:26:05 make progress on understanding the Milky Way.
08:26:07 And with that said, you know, this is just the start of the conversation, we're just telling you you know that this is happening, go to that channel Halo 21 Milky Way.
08:26:15 I've already post some questions they're trying to get the conversation started. But we're having an after party. That's what these separate Zoom's are called.
08:26:25 So, the link is actually posted in Halo 21 Milky Way. I'll go ahead and pin it to the channel, but hopefully you can make it. I'm young and I decided on Wednesday February 3 12pm to 1pm pacific time.
08:26:39 And so that's after the tutorials. Gives you a two hour break after the tutorials, come to the after party, it'll be awesome. I'm hoping to get as many people as possible there just to really kind of settle on what what we want to focus on this week for
08:26:53 our topics. And so the next view that you can see here is this beautiful and maybe we'll see this again this week, many times, is this groundbreaking 3d rendering of the Milky Way's data structure from the Putnam peak and young review in 2012, and you
08:27:12 can see you know historically we've known a lot about the each 121 centimeter mission from the Milky Way Halo and recently we've been able to place distance constraints on a lot of these structures hide from high velocity clouds to intermediate velocity
08:27:26 clouds that are all kind of within 10 kilo parsecs of the Milky Way plane of course there's so much more. There's different phases of material. I think young has drawn the fair me bubbles bear on top of Mary's beautiful PDF figure and then if you zoom
08:27:44 out, right, you see that, I think one of the things that makes the Milky Way really unique among L star galaxies, is this honking Magellanic stream that it has, featuring LLC and the SMC, and I'll tell you, I lost a bet, like five years ago I'm still
08:28:01 bitter about it, actually, it might have been like six years ago with expert Chaska about is the LM see a dwarf galaxy, I think a lot of people think of it as like a low mass galaxy it's got more and I lost a bet I thought it was, it's not.
08:28:13 It's got more than 10 to the nine solar masses of stars in it alone, like the lMz is not a dwarf galaxy, it's interacting with the SMC will hear more about it.
08:28:25 That's still a dwarf good Tina says that that's still at work, not in my mind I feel like you have to be less than 10 to the eight solar masses to be added to our maybe that can be another thing we vote on later this week.
08:28:36 Okay, so I'm finally just to kind of drive home. The idea behind this channel. It's just that you know we're now, we're now holding in our hands all sky maps in each 121 centimeter mission deeper than ever before 3d dust polarization maps.
08:28:58 Ih alpha and mission maps from wham, and and more catalogues of stellar masses distances and ages based on Gaia, large spectroscopic surveys of the Milky Way in combination with high quality data and you can see here I've over plotted the hundreds of
08:29:13 UB high quality UV sightlines that really just present the singular opportunity to study the spatial distribution kinematics of the CGM of the Milky Way in unprecedented detail.
08:29:25 And from an observational standpoint I think we are in the, the age of the Milky Way the next like five to 10 years I think milky way all the way.
08:29:36 Okay. And then finally, not only observations, but I think some of the most beautiful high resolution idealize simulations are starting to come out the one that I'm featuring here is one that is, is I just find stunning is the Tigers model from childhood
08:29:51 Kim and Ostreicher. They have a series of papers highlighting this model one of my favorite things about it is actually just very naturally generates this galactic fountain that alternates and periods of about 50 to 100 million years of outflow dominated
08:30:07 periods and inflow dominated periods, they can predict line of sight velocities. And so it's just, it's, to me it's inspirational.
08:30:17 And so, yeah. And that's, that's all I have to say now young is going to talk about some of the specific questions that we want to talk about in in our conversation group.
08:30:26 Yeah, thank you, Jessica. So Jessica I work together and identify seven topics we would like everyone to talk about, and of course this is by no means covering on are things that are interesting to you out of you.
08:30:38 So, if there are any things that has not been mentioned here by like to talk about, feel free to bring it up during the discussions or go to have post your questions and comments on slack.
08:30:49 The first topic we identify is about the gas kinematics in the Milky Way, and I think Filippo might talk about it on Thursday keynote talk as well. Specifically, as we highlight you know cartoon illustration here, we are thinking about the dissertation,
08:31:05 the halo lagging entities Halo interface. and then the halo rotation.
08:31:10 There are several questions will like to ask for example, on the Milky Way sketch a structure co rotating with a galaxy. And there have been many different kinds of work from each one UV and extra meeting guests as shown in the right panel here.
08:31:25 And if yes, does the guests rotate in different rates from face to face, because the last question we wanted to ask, is because we sit inside a milky way does the halo rotation affects our understanding of the line of sight guess kinematics.
08:31:42 The second topic we would like to highlight is about high velocity clouds and I believe memory will talk about this thought roughly tomorrow's and specific we are interested in what's the gas inflow and outflow rate for the HPC.
08:31:57 And are there any connections between h VCs at media velocity clouds, low velocity clouds and general extended Milky Way cjm. The third question has come up a lot in previous discussions, for example, how to the ionized and mutual guests faces related
08:32:13 to each other. As we heard from drama, a many others have discussed this on the slack. Perhaps the answer lies in the turbulent mixing layer. So we look forward to hear more discussions on this.
08:32:27 The third topics, which will be cover on Wednesdays tutorial by markers plugins and critique, soccer, which is about the Fermi bubbles and the receipt of bubbles.
08:32:39 And so we are not trying to bring that a lot of questions here, but I saw this discussion on one of the slack which is, it's a north pole or spur, which is this feature here I believe it's a north pole or spur a foreground feature much closer to us than
08:32:52 the Fermi bubbles. There a clear distance estimate for it right now. And the other question I would like to ask is under for me bubbles, which is on the left here and that he was seated bubbles, which is on the right here, the same features.
08:33:16 this bubbles agent driven or Supra feedback tree fence and can we see different signatures in it. The fourth questions. It's also related to cloud structures and this is something we saw a lot of discussion, so far as well as about clouds in different
08:33:26 scientists from Cloud this too complex to strings on the left here, we are showing you two figures from each 121 centimeter observations that shows you in the class size distribution emissions.
08:33:52 And on the right here, we are showing you in the UV absorption line data in different kinds of ion, that shows you two point correlation functions of different aisles a showing you how they correlate it spatially, So the questions like to ask is how this
08:34:04 It's not clear, which kind of data we are talking about what kind of connections we are talking about. The other thing we like to discuss his new northern and southern asymmetry, this is something we have seen in both h1 that UV an X ray, even though
08:34:20 we didn't pull the plops here.
08:34:23 The fifth questions is about the magnetic fields, and so we have talked about Mexicans fields in different occasions for example in the fest radio burst tutorial lab by x.
08:34:33 to worse this Muth cloud which shows that the mecca of the feeling that high velocity clouds have a strength about five micrograms which is pretty strong, and that is comparable to the ASM measurement we have so far, related.
08:34:53 Last week we talked about neat non thermo process, so we would like to ask, how can we explain the observed properties of high velocity clouds with the presence of manage fields and Kazmi rates.
08:35:04 Specifically, we would like to ask, how about the velocity mass mythology and concise as you get distribution, how do they change from one model to the other model a which model best to represent you observe data.
08:35:18 The fifth topics.
08:35:23 Ben has quickly alluded to, which is about the observational biases, or how to deploy the ISS, and the CGM, and this is mostly because we sit inside a milky way, and we observe everything from the inside out and go, so I'll let a tutorial on Wednesday
08:35:36 to talk about this topics.
08:35:39 Finally we like to jump out of the Milky Way. Think about the bigger environment which is the M 31 CGM, and the local group mediums and some questions some questions here for example, what's the difference between I'm 31 or Milky Way or are they similar
08:35:54 to each other. And then, is there their local comedian and there's a recent paper by Mary, that talks about this using observational data so I look forward to tomorrow's talk very much, and it finally, and there's a recent paper left by Julia choose which
08:36:09 talks about maybe there's a hot gas preach between the Milky Way, and I'm 31, if so, can we identify that guest bridge in data and can we see this in cosmological simulation, as illustrated here by Luna news out 2014.
08:36:26 Alright so that's on the topics we have thought about but if there's anything that has not been covered here, feel free to ask, I'll post a question on slack.
08:36:36 Thank you.
08:36:39 Okay, thank you john. That was excellent.
08:36:44 That was really nice summary, and thank you Jess for that.
08:36:50 And that was, that was a nice nice presentation that was about 10 minutes, excellent start to the week. I'm looking forward to that after party as well.
08:37:02 Okay, so we have another featured conversation between smell. And now, and I will let one of them share their screens, if they can.
08:37:19 There we go.
08:37:27 And I will mute myself and let small start talking.
08:37:33 I think me I wanted to start first and then I'll go. Sounds good. Yes.
08:37:40 So can you all see my screen.
08:37:45 Yep.
08:37:52 Okay, I cannot hear you but yeah zoom you can't you can't do that. Otherwise, someone will probably shout out something anyway so yes so we have this Hello 21 sm CGM conversation group.
08:38:07 And actually, there are many interesting related topics.
08:38:11 So,
08:38:15 and also I think, is very closely connected.
08:38:23 Welcome weeks, so you know we'd like you to share your thoughts share your questions on this channel and maybe we'll schedule after party at some point.
08:38:33 So,
08:38:38 I backed up I sat in the CGM which is the connection between SM CGM, how,
08:38:47 how they interact with each other, actually on our talk about another
08:38:55 and differences between XM and CGM.
08:38:59 So here I'll three.
08:39:03 No excuses you have a connection problem.
08:39:08 Yes, it's a big problem you're right.
08:39:10 Yeah, yeah, we're having a lot of trouble hearing you just because your, your audio is really breaking up.
08:39:18 I don't know if there's another like microphone you can use or
08:39:26 what I can do, maybe I'll stop meanwhile him yeah you will try to fix that. So I'll jump to. Okay, sounds good. yeah. Okay, so I'll jump. Okay, so I hope you can hear me, and also see me see the presentation.
08:39:41 Yes. Okay. So basically what what we thought could be nice for this channel, we separated the discussion of the ASM CGM into two parts.
08:39:51 One is a connection between the physical connection. So the interface of the is Sam and CGM and the flows of gas between the is M and CGM, and that was me or me I wanted to talk about and she'll talk in a minute.
08:40:08 and the other, I think interesting aspect which I wanted to bring up.
08:40:14 stuff that we talked about in the ASM community. And now you talk in the CGM community, but you know the scales are different, and the temperatures are different, but it's often similar processes.
08:40:41 And the reason why I think making these analogies might be very useful is not just because, you know, it's like a new agey thing, everything is the same and that's another thing.
08:40:52 It's really I think that if you have overlarge skills of, you know, physical skills energy skills temperature skills, things that does similar say the multi phase nature of the gas or the role of to bill and things like this.
08:41:11 And you are able if we're able to make this full analogy list and identify what is the physical process that that makes this a the gas multi phase or what's the role of turbulence.
08:41:25 And now this applies on very large scales of energy and density and temperature, then we might be getting the you know the drill physical essence of the process.
08:41:36 It's not just a active at some environment like some temperature range but in large, a range of environments and I think we were able to get a more a deeper insight.
08:41:50 So I just bring some few ideas but my hope we will have more so for example we had this discussion of the structure of clouds, or is it cloudy or misty.
08:42:05 And also there's the question of, is it, can you really talk about discrete phases let's say two temperature phases or density phases, or is it really a continuous distribution is there pressure equilibrium between the phases if there's such or not and
08:42:21 the role of non thermal pressure so all this is also discussed in the context of is all these questions and they're not. The answers are not clear.
08:42:33 For me, listening to this and also trying to connect to what's happening in the is am I feel it's often the question. I like the drama and also mentioned this a comparing this a cooling time to different other times kills, that's often the question of
08:42:48 comparing the cooling time to different dynamical times and then what's the dynamical time really depends on where are you at the CGM is and also, even within these phases.
08:43:01 So for example, for the dynamical time. If turbulence is important could be in the is m often this is discussed this could be the turbulence tone, turn over time, or the coherence timescale of colliding streams for the cooling time, then you get a dependence
08:43:18 on things like the metal Alyssa T, and the mean gas pressure density which can be also related back to the feedback like supernova solid feedback, say papers by Kim and all striker suggest.
08:43:33 And just to give an example, I show here a plot from AZ free paper. So they made a 2 billion box simulation that is multi phase was cooling and heating so they shake the box continuously, and they get these multi phase structures of these are cnn called
08:43:50 neutral a medium and warm.
08:43:53 This is the density, and what they showed in others as well it's just an example is that, if, if you change the level of turbulence how strongly you shake the box.
08:44:05 Then you at first if you barely shake it you have really these distinct phases of warm gas, WNM and CNN, these two peaks here and he also seen in density.
08:44:17 So in the best the contrast is invested temperatures they have pressure equilibrium. But as you start shaking the books harder and harder, you start losing these two phases and you get a continuous distribution, and you start to populate all the density
08:44:30 and temperature in betweens in between.
08:44:33 and this is actually observed.
08:44:36 Of course this is a very ideal example, diverse in practice is not just shaking a box that's injected by different mechanisms and that's part of the difficulty, like supernova or gravity and this is another view of the same idea so this is low turbulence
08:44:53 where you have this multi phase of low density and high density. cm cold and warm gas and this is it, is it high turbulence level.
08:45:05 It high turbulence levels. And this also connects to the question of pressure Libra because for example in the AFM. There's observations of of the pressure of the thermal pressure via up lines of cc one, and the distribution is quite wide.
08:45:21 This is often compared to the simulation that explained this distribution via the act of turbulence.
08:45:29 And finally, I just wanted before I pass it to me to.
08:45:34 Meow. I wanted to also just say one word band you mentioned Gaia. And it's actually amazing what the guy is doing to the ISS I just have one example I wanted to show you, you still see my screen Yes.
08:45:53 So, this.
08:45:55 Yeah. So what you see here is, is a surfaces of density of five and 25.
08:46:05 The numbers here are parsecs, and the center is the sun, and this is not a simulation.
08:46:12 This is an actual observation in three dimensions.
08:46:17 So now with Gaia so what is happening is people were able in the last few years to produce three dimensional maps of the dust around us. Using a guy because now you have the extinction maps of stars from dust and giving you the cone density of the dust,
08:46:37 between you and different stars but now this guy you also know the distance is very accurately to many many millions of stars around us. So combining the column density and the distance, you get the volume density so people started to produce this very
08:46:51 This is one passes resolution, three dimensional map of the dust around so you actually starting to see the structures in the ASM. That's a privilege we have compared to the CGM in three dimensions and I think this will also revolutionize the field was
08:47:09 a guy. Okay, so that would be it. I think from my side and maybe hopefully young is now fine with the internet now.
08:47:30 So, can you see my screen Can you hear me well. Yes. Yep.
08:47:38 I don't know what's happening and maybe it's the storm, right outside the window, um, but now I connect with Ethernet so hopefully this time it will work better.
08:47:46 So yeah thanks me out for the very nice introduction on the analogies and, you know, differences between them the CGM.
08:47:57 I will propose some questions from another angle, which is the is Sam's connection to CGM like I Sam, how does that become CGM how CGM become I said batter, a backer back.
08:48:12 And you know what is there, you know, there are connections, basically. So I won't. I will propose three questions that I find interesting for us if you think of other related questions for fly some CGM feel free to post them on slack.
08:48:27 So, um, you know, the first thing I I'd like to know your thoughts, is about the two views of this, you know I sent CGM. And we know that you know this on the bottom left this is the down the barrel absorption of the interstellar medium and the way you'll
08:48:51 have a star for me going on in that this can you have this, you see those strong Interstellar absorption lines and, you know, a lot of gas is flying out at high velocity and they usually have very large column density.
08:49:06 Another view is this above the barrel, I just made that up but you know what I mean this, you know, without absorption line, and then you don't see the disk but you see through the Halo, and you also see you know those, you know, absorption lines and
08:49:23 then they have, you know, velocities, you know, offset compared to the galaxy. So my question is hard those two views connected, or maybe not connected.
08:49:38 So, we expect you know those down the barrel, up to, like, those gas that, you know, make those as an interstellar medium absorption lines, do they become part of the above the barrel CGM absorption, or do they not so if they are not connected, what happens
08:49:58 to those down the barrel as them absorption those guys, what happened to them.
08:50:03 So that's that's my first question, are those two views, connected or not.
08:50:10 The second question is that, you know, besides those cool outflows that we often observe. Don't forget, they're this million degree hot outflows. And usually it's hard to constrain you know what is the mass loading the energy, you know, loading factor
08:50:28 associated with those hot outflows and in recent years, there are many those killer parsecs skill, small box simulation that zoom in on to those outflow lounging region, and see you know how close are being launched and repeatedly was being seeing is
08:50:45 that, you know,
08:50:49 the hot outflow actually carry, most of the energy and the medals, compared to the cool outflows so here I just you know put together all those results from small box simulations, they usually the hot outflows campaigns order of magnitude more energy
08:51:04 and the cool outflows, and also is not hard to imagine that they also have very large specific energy, meaning that they can't travel much further than the general pool outflows.
08:51:15 So the second question is, you know, what do those hot outflows do once they are launched outside of ICM, what do they do, to the CGM, and what are the observational Avenue related to this question.
08:51:31 The third aspect is about elliptical galaxies. So don't forget that you know not only star for me galaxy have SM illiberal galaxies has asked them to, and is not as boring as we have thought before.
08:51:46 So for example here just a very simple experiment, start out with uniform, how as them and then just have, you know, type what a supernova exploding in them.
08:51:57 And what we find is that very quickly, the medium become very homogeneous. And, you know, while the medium is being overheated by supernova At the same time, cool gas condensed out of this hot medium, and also the turbulence there is very different from
08:52:15 the usual conventional tour, you know driven turbulence box that, you know, the results from there. So, is definitely not boring and there's a lot to learn from it.
08:52:27 And the CGM of passive galaxies not boring, either. So this is work from Bariza Hedy and they find this super sola ions will offer ratio and CGM of passive galaxies.
08:52:40 So that means that that this life stage of evolution of those passive galaxies. Those I on a reached essence to get out of the galaxy, and also condensed to become those who absorbers that, you know, you know, twice the by those, I am tool magnesium too.
08:53:01 So, the third question is, how does the yeah I Sam connect with a CGM for those passive galaxies. So those are my three questions but of course there are many more things to discuss related this as I'm CGM connection for example there's this Kayla interface
08:53:19 there's high velocity clouds I'm sure we'll hear some from the keynote speaker this weekend snacks and, you know, other questions include the How does CGM dry Sam or rejoin us and cetera et cetera.
08:53:31 So, anyway, those are my questions and I hope to see you, you know, share your own thoughts and questions on the Slack channel.
08:53:39 Thanks.
08:53:42 Okay, thank you