courting.
Chris Damerell: Thank you very much for the introduction ivana i'm and lovely to see many of you here today i'm particularly grateful to give this talk.
Chris Damerell: I should explain what i'm saying I mean obviously everybody says, you know glad you invited me blah blah, but this is rather special, I think that I could be wrong, the reason I think it's rather special is that the energy frontier for the policy minus collider was first.
Chris Damerell: Seen in that sense of the TV scale 30 years ago 19 9032 years ago and, since then, at that time we thought yeah we'll have it all running up and running in 10 years.
Chris Damerell: there's been so many setbacks over the last 30 years, I can tell you, and met many wonderful people that participated in the effort and have been you know frustrated by those setbacks it's been a very difficult time.
Chris Damerell: I think that now we see some light at the end of the tunnel i'm participating in the snowmass workshops in the US and that's where things are moving and that's what i'm going to tell you about so.
Chris Damerell: The talk is divided in two parts, the IOC unsecured I would say, any but i'll see because that's been around for it that's what.
Chris Damerell: i've been reading all the time, but see cubes and new idea and.
Chris Damerell: And then i'll move on to also new ideas for the pixel tracker which we've talked about before, and many of you will have heard me talk about that, before but there's some very interesting developments on that as well, so those are the two topics.
Chris Damerell: And so, when the energy for it, when I start with the livingston plot, some of you probably.
Chris Damerell: I don't know if everybody has seen the movies and, but this was this one particular one was produced at CERN in 2010 the start of the latency and.
Chris Damerell: it's called the living subplot because Stan livingston was a Co inventor of the Cyclotron and also co inventor of strong, focusing in the in the.
Chris Damerell: brookhaven.
Chris Damerell: And so that was the beginning of this sort of you know exponential rises bunch of time of of the energy frontier First it was done in the context to fix target, but now collider.
Chris Damerell: Be careful it's the constituents central message that's why the proton proton free Bobby are all diminished by a factor of six because its constituents and.
Chris Damerell: So, but of course he plus C minus then it's just the actual collision energy and so it's interesting to remember that.
Chris Damerell: There were some unexpected discoveries the charm co op was discovered in E, plus a minus in at sphere in 1974 and the glue on 1979 PETRA now both of those you can say.
Chris Damerell: should have been discovered in the hadron collider the asr, in particular, and the reason they weren't is a long story, but it's just an indication in the case of the.
Chris Damerell: Of the job site was just a simple question of the trigger that they've got wrong on the asr so.
Chris Damerell: This is just an example that we have needed historically complementarity between these and so it's probably well, in my opinion, completely incorrect to say Okay, well, we just carry on la FC the.
Chris Damerell: hl llc and the FCC Ha ha and everything will be revealed i'm pretty convinced that we need the plus or minus.
Chris Damerell: Energy for it to be moving as well at this time it was thought that there would be an irc around 2020 years was at that time.
Chris Damerell: very much that the idea, so if we just quickly look through a synopsis in 1990 we finally got SLC and slt working, and that was really the thing that open the gate to talk about a next stage of.
Chris Damerell: of E plus C minus energy frontier machine which was which which appeared in in the in various forms, nlc was the slack.
Chris Damerell: Proposal tesla was the was the daisy Chelsea Japanese and click at CERN so we had many labs coming with their idea and, at the first international workshop you on vacation absolutely marvelous summary talk.
Chris Damerell: Both on the machine and on the physics and he suggested first physics about 10 years time 2000 and well, a lot of bad things happened after that, including the old vic was was unfortunately killed in an accident in.
Chris Damerell: tesla was dropped the the daisy proposal, which was the front runner at that time, decided to focus on European xml.
Chris Damerell: I took was formed international technology review panel and very bearish they recommended the superconducting rf option in 2004 and most labs.
Chris Damerell: cooperated to make it work, including slack over they wanted the room temperature machine 2000 that everybody thought fermilab would be the natural host for that 2008 the complete.
Chris Damerell: You know bombshell the doa and for me that dropped it completely said they weren't going to do it there's a story behind that which I want to tell you now.
Chris Damerell: Japan provisioning offered to host it and most labs again cooperated with that there's 14 years ago and.
Chris Damerell: Currently we're in an absolute stalemate situation is opposition from kk not all of kk obviously some skepticism from the funding agency in Japan.
Chris Damerell: They have put it fairly recently as irc seems the three legged stool with one week one Europe seems not to be interested, why do they say that well.
Chris Damerell: they've had meetings they've come they've talked to the UK, French and German answer and people and then at least twice in the last two years, maybe more for all I know.
Chris Damerell: And they could be right, many and you're happy to focus on FCC which will for sure, be a wonderful extract you have nothing against it whatsoever.
Chris Damerell: If it can be afforded and so on it's a very expensive.
Chris Damerell: machine but it's really a quarter second terms of the energy for it, because you can't go any higher than that.
Chris Damerell: The circular machine, at least I can imagine, so is a recent twist in all of this, that is superconducting or F, which was chosen back into some for the preferred technology.
Chris Damerell: Given exciting developments in what the select people nickname cool copper cool copper collider cq.
Chris Damerell: What i'm saying here is there's room for a new idea so let's look at what that is so here is what one of the early snowmass talks last last month January, and you see high energy electron collider concepts listed.
Chris Damerell: And there were nine of them increasing speculative notice, I would say, once you come to laser plasma plasma driven and Wakefield there is none of them mentioned luminosity.
Chris Damerell: that's the problem you probably can get a very high energy that way, but I mean, I was in a workshop 1980 I guess it was in Bari where.
Chris Damerell: john Lawson was in the audience and he asked some very tough questions on those options and at that time regarding the possible.
Chris Damerell: admittance that you could ever achieve, and I think that's still true that problem, there are also, as you see, on this this mian can I have a couple of me on colliders now there.
Chris Damerell: I think it is still true 2000 Bob Palmer presented that it's no mess and the detector was then certainly.
Chris Damerell: No more than an aspiration, I think, came along, in a recent talks, it said the same thing it's still an aspiration very hard to see how to do a detective for that for that machine, I mean Bob Palmer was saying.
Chris Damerell: You know, on the debt time scale everybody using diamond detect as well.
Chris Damerell: Even if you did the electric the relationship wouldn't work, so I don't think there's an answer to that one so anyway, but as you see here you've got irc cq click the CERN.
Chris Damerell: which is now on know hardly worked on and researching the neck from brookhaven from.
Chris Damerell: From fermilab which is, which is shown here, this is a very confusing slide and and i'm not going to talk about it at all, except to just point out that irc which is up here.
Chris Damerell: As a footprint for 500 let's Just compare like the light for 500 GB a footprint of 31 kilometers and.
Chris Damerell: that's what we've got used to over the years, but here, you see, see cute with the footprint of eight kilometers for 550 gv so you've got to pick your ears up when you see that so that's what's that's what's coming coming up Okay, what happened in.
Chris Damerell: The nlc ta and i'll see.
Chris Damerell: test accelerator was, in the words of critics melting a lot of copper the item division decision in favor of zebra was reasonable at the time, because the warm machine was not was had a lot of trouble.
Chris Damerell: Now, of course, is that that didn't mean that people stop working on one machine is a very great importance for commercial applications high gradient.
Chris Damerell: expects resources for baggage checking things like that so it's been worked on commercially as well as for the high energy frontier and the the one who.
Chris Damerell: has absolutely brought this to light is immediate nanny young accelerator physicist, with very bright colleagues at slack and they've to devise a new approach, which is a cq.
Chris Damerell: The main there are two main features The first one is that the accelerating structures are would use the term separated function in the same way as as.
Chris Damerell: Strong focusing was separated function for every cell in the in the in the accelerator, you have a large aperture for our delivery.
Chris Damerell: and small beam apertures instead of combining them into one, which is what everybody has done up till now, it turns out that within computer optimized cell shape design, you can reduce the big fields away a lot.
Chris Damerell: The other thing is low temperature operation liquid nitrogen which by the way, is pretty cheap for much reduced factor to surface reduce resistance reduction.
Chris Damerell: And then you can raise accelerating 250 560 megabytes can meet meter compared with 31.5 megabytes for me to for the superconducting my erbium of IOC and that's the key that's the key.
Chris Damerell: step forward so here, you see the idea explained, you have in the Center these funnily shaped.
Chris Damerell: Accelerating cavities with small average was 2.62 kilometer radius and beam going through those and then the rf is fed with two channels are if they are coming in here and here.
Chris Damerell: This is a plan view So these are actually side by side in the structure and so what you see here is you've got.
Chris Damerell: This one, and this these these two cells fed from the top, and then these two cells from the bottom and so alternating as you go along and it's a pi mode acceleration and so you know the colors represent the the phasing of the rf a cavity by cavity.
Chris Damerell: And, and, as I say.
Chris Damerell: It has been calculated but.
Chris Damerell: he's barely demonstrated that you can get to a very high gradient with this with a structure.
Chris Damerell: So here's the real thing this is so far they only made a half, these will come in one meter links, this is a 50 centimeter length.
Chris Damerell: structure and you see the accelerating the cells in the middle and you see one way, but here, and when you're running along and these ports, which will link to the accelerating so that's how you need it.
Chris Damerell: So that it's made in two halves it's made by cnc machining after the machining no post cnc finishing now if you know about the.
Chris Damerell: Complicated post processing of those Nairobi and kennedy's to get them to have a sufficiently adequate surface finish it's unbelievable the difference this is inexpensive mass production don't touch them you put them together you you.
Chris Damerell: connect them with high temperature to to have the high temperature gold copper braise and then there you are, and they've tested them up 260 megabytes for me to, including the beam.
Chris Damerell: And there's another point in all of this, which is that I have this evening, but maybe maybe wrong, but I don't think that these these structures one meter length.
Chris Damerell: you'll see later how they get edit together and to make up modules are pretty robust with respect to operational accidents what am I talking about well, it was a fire in the SLC damping ring, which then.
Chris Damerell: breached the vacuum and so you had smoke inside the the.
Chris Damerell: damning ring on the walls, the splice during failure lsc they've been some pretty bad accidents, not to mention earthquake damage which can also easily.
Chris Damerell: reach a vacuum and the point is that, even if exposed to smoke copper cavities can be cleaned by beam scrubbing so very well defined.
Chris Damerell: process takes a while that that damping took some weeks of running a high intensity been through it and slowly cleaning the.
Chris Damerell: cleaning out the cavities but for super good and you can't do that because they just they just quench every time you were trying to such a thing so.
Chris Damerell: So I think there is a problem that I did actually raised everything Evans years ago and and his reaction was you have any of those things have to be a disaster, but I think it doesn't need some kind of billions of dollars gee you have to have some sort of risk analysis for this thing.
Chris Damerell: Okay, so this shows you the benefit of cooling, so what you see here is all sorts of copper and gold copper and also stuff.
Chris Damerell: That limit on the gradient was this is the breakdown probability and so you've got pretty much a hard edge around the 200 megawatt the meter and here you see a low temperature it's very little different to 77 kelvin, which is much more convenient and you can go up to like the 250 so.
Chris Damerell: operation with liquid nitrogen is convenient and what they're thinking of is a is a.
Chris Damerell: pipe about 660 centimeter diameter and at the bottom, you have the cavity in the liquid, and this is in the vapor return vapor comes up.
Chris Damerell: At the top oral cavity so and it's a modest cry a cryogenic client it's completely modest on it, so the accelerator.
Chris Damerell: yeah is for do you have a crime modules nine meters long so here you've got eight meters of active acceleration So these are one meter.
Chris Damerell: or of structures in pairs so there's 2468 liter of our structures and there, there are quadruples permanent magnet quadruples as well in there, so you've got for nine major lengthy but eight meters of active accelerating structure and.
Chris Damerell: The.
Chris Damerell: And the next step that the spec people and anya and co hoping for, is to build a complete crime module eight of these structures together using commercial see band class drones and that's kind of what you're talking about four of them per cry module now those are expensive this this.
Chris Damerell: i've got a COs COs figure it's similar to the IOC for the for the 250 GB machine.
Chris Damerell: In cost with commercial classrooms, but when you want to go up the hope it well there's a huge activity going on worldwide on developing cvent flies drones and.
Chris Damerell: hero all the labs involved and industry as well, and the costs are really coming down, I mean there's all sorts of tricks that they're using to use, for example, room temperature simple than acting.
Chris Damerell: was to two parts of the classroom structure and some i'm not an expert, but I can I just saw one talk on this stuff and it's really moving rapidly says no question that these power.
Chris Damerell: sources are going to become you know much more affordable in the years ahead, but so far for 250 GB they're assuming the commercial ones that you can get now So what are the next steps for cq.
Chris Damerell: It would be.
Chris Damerell: really think it would be really helped to have no authority to comparison, because if you look at that thing I showed at the beginning of all the different.
Chris Damerell: You know options for the energy frontier is very confusing for non experts and even for experts what's the message and the thing is that.
Chris Damerell: The.
Chris Damerell: If you're not careful, this comparison i'm just making between llc and it's eq could get lost in the noise.
Chris Damerell: And what we're hoping for, is to get an ex an impartial expert now who who do you think that could be we think of somebody like Ryan i'd brinkman right, I mean he's European xml.
Chris Damerell: Wonderful accelerator man and or even there's another guy from Hamburg university both can heal it, who is absolutely brilliant and.
Chris Damerell: But he's retired but somebody who is who is impartial to the linear collider world to give an invited talk we're hoping during this there's a.
Chris Damerell: collider discussion session at snowmass end of March, end of next month and we're hoping to get some sort of you know, honest compressed that'd be a wonderful talk and get somebody to do that.
Chris Damerell: You know, we don't want to have to convene another it rp and all that stuff and spend years touring the world looking at all these options.
Chris Damerell: It would cost about 100 million dollars to make a fulcrum module, as I said, the closer and develop will make that that cost per crime module.
Chris Damerell: drop as time goes along, even with a higher gradient that you need the idea is to go from 250 to 550 with exactly the same accelerating system, but just to run at a higher gradient it's.
Chris Damerell: even remember 70 megabytes per meter for 250 GB and 155 megabytes for meter four and 550 GB so that's the other that's the plan, and so what you need is to completely change the the.
Chris Damerell: The.
Chris Damerell: place around supplies, or to go to the higher power.
Chris Damerell: Of course, this is only going to move forward if we get strong backing from the do we, we will be going into the snow mess and then.
Chris Damerell: P five process, hopefully that will come out of it and, of course, another critical thing will be who's going to be an extremely lab director, I have no idea, but you know, the thing that killed it in 2008 was the so called hadron alliance people who didn't want a nice.
Chris Damerell: Sheen fermilab and let's hope the new Director doesn't have that opinion otherwise they're not going to go anywhere fermilab, but there is a fermilab site filler collider working group and they've given great encouragement to cq so.
Chris Damerell: I mean it's it's a natural for the website so that's that's where we are on it.
Chris Damerell: And if they were to be funded, then the hope is you've heard this before I think before I 2014 to have the machine up and running, but as you as you've heard that's not the first.
Chris Damerell: projection that's been made about the linear collider so um yeah and the cost estimate is for 250 is $3.7 billion.
Chris Damerell: that's without Labor and and without contingency do we would always put in contingency on all these things, and most of the components of that cost is that are derived either from irc or from click so.
Chris Damerell: I don't think they're there you know completely unreasonable I haven't followed the cost estimating process, but I could imagine that's probably a pretty good estimate.
Chris Damerell: So that's all that i'm going to say about cq um so I bet it now move on from the interest of time, the pixel tracker so.
Chris Damerell: We need whichever one gets built an excellent tracking system minimal material, including the forward region, I mean that's The problem we had a detector review in 2007 for tracking that i'll see and.
Chris Damerell: We were concerned about the proposals, most of them I told was one of our very eminent reviewers said, well, is it tracking is always got alien the Ford reach out to anyone, but that's that's not good enough, we were at blue see when you're talking about the.
Chris Damerell: TV scale you're talking about multi generations always got one or two jet's going in the Ford regions a card afford to just you know not do a good job on them, so we really need a good.
Chris Damerell: procedure there by 2008 we had a proposed solution, this was a silicon pixel tracker that you may not have heard about before from Constantine seven off, it was a brotherhood at that time, and he gave a talk at the IOC workshop in sendai in Japan.
Chris Damerell: It didn't go down with a huge enthusiasm, the reaction from both the SI D and the iot people was it's a case of the better being the enemy of the good, we need to be running by 2020 so we're going to stick with the Microsoft Craig there was the SI D, I already people have.
Chris Damerell: A tpc.
Chris Damerell: Well, of course, 2020 has come and gone and during these intervening years is not dissimilar to what I was saying, on the accelerate.
Chris Damerell: This SPD contract is going to increasingly attractive as a result of developments in pixel design.
Chris Damerell: pin photo diets now probably not many of you know what been fertilizers and we'll explain that and also other maps based tracking for Alice.
Chris Damerell: Absolutely wonderful the ideas to now moving to Ikea three fantastic developments there so by the time of lc ws 2021 which was some sometime last year I forget the month.
Chris Damerell: i'm constantly presented an updated conceptual design with these features built in, and now, is it people jumped onto it immediately and said oh it's obvious, we should be crazy be doing that, so it will be a.
Chris Damerell: pixel tracker but what about the details of that tracker so we're going to look at the design concept we've thought about it in detail for IOC it's applicable also to cq but.
Chris Damerell: The time structure is different, so it doesn't translate immediately, so this is the sad microscope tracker and the previous baseline of the blue things, these are 12345.
Chris Damerell: layers of barrels and for four discs and then there's an inner region here, which is this is this is Gray, is just the support structure, and then there is a vertex detector and then some more forward.
Chris Damerell: tracking inside that we're talking now about the main thing okay that's that's what we're focusing on here So what do we want to do well to first approximation, we just replace.
Chris Damerell: The barrel, and the end caps with pixels, so this is a view of the thing with with the with the end not shown so they just emitted from the drawing for clarity and what you're seeing is then this array of.
Chris Damerell: Of pixels maps senses and the each one is eight by eight square centimeters 2.56 megapixels, and so what you then get is a tracking system which has.
Chris Damerell: High transparent transparency will come to what the material budget is it three 3% of radiation name for the whole thing.
Chris Damerell: Times that's for normal incidents so there's an obliquity factor which is at worst 1.414 sort of 45 degrees incidence so it's got.
Chris Damerell: The trick is that the the tracking layers integrate the signal through the whole of the bunch train.
Chris Damerell: to minimize power now when you hear that you must do what are you doing you're adding in all the other thousands of have.
Chris Damerell: a bunch of in the train it turns out that the hit density is sufficiently low that that's with it with the granularity of pixel tracker.
Chris Damerell: that's not a problem you do need to sort all that out, of course, you need need to reconstruct the tracks associated with the event, not with the.
Chris Damerell: All the other stuff and so you do need single bunch timing information which is planned, we get that from the vertex detector and from a thin dedicated time they're just before the equal.
Chris Damerell: So the whole point is to try to minimize the power dissipation and therefore the material air cooling.
Chris Damerell: Total dissipation of about 100 Watts for the five layers and the sensors about 100 micron thick the low mass support structure, then gives us point 6% which times five gives you the V percent of them.
Chris Damerell: Radiation and the pixel size, we again earning on the large side and because, again, the more pixels the more power.
Chris Damerell: And so, he told me a 50 by 50 micron pixels which by partial depletion, we believe that this is back of the envelope calculation since 2008 when constantly presented it.
Chris Damerell: Again, about five micron precision and that has to be simulated and.
Chris Damerell: i've got good news on these things which has to come up but that that last service simulated say overall system 28 megapixels 70 square meters of silicon which in 2008 sounded like a lot.
Chris Damerell: it's much less daunting now because of what's been happening on Ellis and.
Chris Damerell: We also, why do we want square pixels there's a whole argument about that, for various reasons, and I mean another option considered as it is 2500 micron pixels.
Chris Damerell: Both of these need to be simulated there are all sorts of details, but some of us.
Chris Damerell: very convinced of the bondage of having the same precision and the opposite, as in the office I view, although us off information momentum the asset for.
Chris Damerell: For linking to the vertex detector where of course as far as secondary vertices that concern both us are exactly the same importance.
Chris Damerell: Right so so here, you see, on the original plan the vertex the things in red are giving you a single bunch of timing vertex and three layers of.
Chris Damerell: of time to timing layers just before the before the call, which we think we can probably also do with air cooling it's not proven yet that.
Chris Damerell: That some under discussion, but as well there's a recent development, which is that it may be very interesting because of his interest in the second generation.
Chris Damerell: Maybe anomalous with respect to the standard model that.
Chris Damerell: tagging of chart of strange jets maybe a very great importance, and so we are talking there about a P is rich based the ID system that I.
Chris Damerell: just mentioned later can't include that in this talk is in time but that's something we're also studying the vertex detector will provide the tracks, with a single bunch of timing at the small radius and and then this this thing or something, including the rich system before the ICO.
Chris Damerell: All of the tests to be simulated get mentioned these things because there's almost no effort in si D there's hardly anybody working on it it's really decayed to a lower because you know.
Chris Damerell: Who can work on something when there's no known timescale, so we have we have snowmass is the place where we're we're actually getting a lot more interest from young people, and I hope we're not going to be.
Chris Damerell: You know, misleading them right, I mean we don't want people to stop putting their career into this and then it all collapses so news from last week.
Chris Damerell: Andy white of the University of Texas arlington is hoping to resurrect and update the silicon.
Chris Damerell: tracking simulation starting at the end of March, and this is all because of this new spirit of optimism that is not the response.
Chris Damerell: To work on the on the policy minus energy frantic okay so.
Chris Damerell: As I say, in 2008 there's 28 gig of pixels we're pretty pioneering but now I mean Alex he is there, wonderful ideas to which is already installed not you're running always equal.
Chris Damerell: At not up yet, but travel half giga pixels 30 by 30 micron pixels and.
Chris Damerell: 10 microns so we're taking 70 mark and so it's being compared with that but, nevertheless, you know we're talking about some way in the future.
Chris Damerell: And even more exciting is the work of the crn wp one point to live by walters noise for stitched maps devices for Alice.
Chris Damerell: It is three using the 65 this is, it has to 65 nanometer technology know the Tower jets which I mean did you see the news I think just yesterday, the Tower jazz i've been bought up by Intel and.
Chris Damerell: Hopefully there will be the same thing happened with etv they were they were bought by teledyne so no teledyne need to be.
Chris Damerell: And and most most of these takeovers, these days, it seems to be that they it only helps the smaller company, because they get.
Chris Damerell: All sorts of benefits and the bigger company is not buying them up to asset strip or any nonsense like that is absolutely wanting them to continue and do and continue so I don't think is any problem with the charges to be concerned.
Chris Damerell: Okay, so here's what's going on in this was Moses talk last week, and this is a 30 centimeter 12 inch wafer and so it's a way for scale.
Chris Damerell: Now this at the moment is one D stitching each of these is a separate.
Chris Damerell: structure and they will do 2d stitching eventually, so this is 25 centimeters each one by whatever it is about 1.5 1.4 centimeters.
Chris Damerell: And so, each of these is a stitch of structure which has got 10 Middles they call Middles and to end so there's 10 of about 2.5 centimeters them to make the whole thing 25 centimeter length.
Chris Damerell: And the thing that blew my Oh, and each of these is actually not one it looks like when exactly to one of them is the.
Chris Damerell: mo SS and I have to remind myself emos own monolithic stitched sensor.
Chris Damerell: Which is the big one large area when we had continue so long way across, and this is the mo St, which is the monolithic stage with timing more ambitious and so there's a.
Chris Damerell: scribe line here, where they will be separate so this will be one which is only two and a half millimeters wide and then, this one is.
Chris Damerell: about the 1.3 cinema 1.2 centimeters wide and with different pixel sizes and all the rest of it, the thing that blew my mind was also mentioned that the.
Chris Damerell: That the designer checking of the full wafer needed a monster machine, he said 500 gigabytes of Ram and it ran for 24 hours to do the design you're checking and it found a few bags so.
Chris Damerell: I mean, this is just incredible on the scale of what what I was ever used to I mean we did have that's what I wanted to just mentioned, we had stitched devices for.
Chris Damerell: SL D and that's what actually saved the vertex the technology has come to that, to just as a reminder so here, you see the SL the original.
Chris Damerell: So the vertex detector it's on a 2.4 centimeter bean pie, which would never happen there's radius and it was supposed to when when it was all planned it was going to be a one centimeter radius but then the.
Chris Damerell: mach two people went in before Thank goodness for that and found that the backgrounds are absolutely horrible so there to expand your 2.4 centimeters, why was that this was due to.
Chris Damerell: The beam was very tiny going through the IP and and the machine people at that time had believed this was BERT Richter, particularly by the way, that that that's what you'd get and therefore you could make it well, he said, the impact would be the size of a drinking.
Chris Damerell: Well, and no because there were non gas entails on the been sending out to about 10 segment, so you know it was far worse and and they would then of course have to be colonnaded.
Chris Damerell: And the column eaters would be shining the synchrotron radiation and sorry with with with very charming and.
Chris Damerell: And then again you'd get fluorescence X rays, and so all this stuff that we saw in our vertical detector was mostly soft X rays it's not as bad as it looks because the skies these blobs.
Chris Damerell: indicates the energy and so, most of them are actually single pixel, and this was 120 megapixel system, so it actually was a very small occupancy.
Chris Damerell: And indeed, thank goodness for the drift Chamber on this particular event when you reconstructed from the drift Chamber you found any then when you linked.
Chris Damerell: In the vertex detect it was a nice new plus B minus the better, so when the background was not a problem but and it had been a problem for the Mark two.
Chris Damerell: And in fact the Marty micro strips and far less of granularity but said by the machine guys I bought SLC to its knees, with every time they started to run the verdict service, I know we.
Chris Damerell: gotta gotta improve the backups and they had a hard time to do that.
Chris Damerell: Anyway, so this is what we built the best we could do with a two point here's the FC to the 2.4 centimeter the empire and it wasn't what we wanted our all.
Chris Damerell: And so anyway and 93 when we install it, I went to etv to give him a talk.
Chris Damerell: about this vertical detector and how we were going to take data and we're so happy.
Chris Damerell: And, but then at lunch David Burke said, you know, is it that's very nice detect he says, but we could do much better now, so I said, what are you talking about.
Chris Damerell: He was talking about stitching so they had each of your now developed stitching and so, so they came then with development with.
Chris Damerell: A much larger, this is, it is a sort of postage stamp side, and these were eight centimeters by 1.4 centimeters with three Middles and two ends.
Chris Damerell: And so that's exactly the same principle as to what the maps guys are now doing, but I mean it's just far more complicated now so that then gave us a much better performance.
Chris Damerell: detector, this is a BF C three, which is those things because it wasn't just that it was one eight centimeter on one side and went on the.
Chris Damerell: 16th enemies of active length and that gave us a very nice vertex to take a well matched in angular coverage and so on to the to the beanpot so.
Chris Damerell: It was thanks to the ECB stitching that that worked up, and of course the Ellis people are now doing.
Chris Damerell: Exactly the same thing, thanks to the Tower jazz stitching they're able to go to the kind of detect to they really wanted build for the future of this is just a photo of the xd three and and you see.
Chris Damerell: here's the eight centimeters length and then, on the other side, this is on a beryllium support support matter okay.
Chris Damerell: Right, so I mentioned also that we want a new technology for the new a different technology for the.
Chris Damerell: pixels, which is in the form of pin photo photo diet pixels and here you see a very nice review Article from 2014 these things have been around from the.
Chris Damerell: Well, even before the first CCD is 1970 the pin photo died, is a very old concepts old and respectable concept is now use pretty much everywhere, he says here.
Chris Damerell: The pin photo died as a photo to take substructure using almost all charged couple device and CMOs imaging sensors due to its low noise high quantum efficiency and low current.
Chris Damerell: And it's indeed what you've got in your in your in your phone cameras and it's often overlooked by the http maps community in some cases for ignorance reason of ignorance and in other cases for good reasons, because it has it.
Chris Damerell: Absolutely has its limitations and so we'll look a little bit at that now, so this is these these slides are from constantly in seven off.
Chris Damerell: At Center for electronic imaging Open University, where he is I mean Eric fossum who wrote that paper was sort of the world expert on pin photo diet pixels at that time he's now must be.
Chris Damerell: approaching retirement and Constantine is an hour on the world scene, very much the world excellent amazing we've got world expert on that stuff.
Chris Damerell: In the UK, and so, basically, what you've got is a structure in which you have a number relatively large area pixel and a very tiny charge collection and sensing region.
Chris Damerell: In the in the middle, or on the edge of the pixel and so during the integrated single integration you build up your signal, and then the signal is just sitting there and then, when you want to read out.
Chris Damerell: So it's a it's a you know you've exposed your picture on your camera, whatever your pulses transfer guide and and then the signal.
Chris Damerell: transfers to the node and that then gives you very, very good performance in terms of conversion game before Fernando node capacitance.
Chris Damerell: and very low noise sub single electron is quite routine in scientific devices and moderate radiation hardness now do you consider the modules if you're if you're a fit person you're going to this tragic.
Chris Damerell: So so that's the reason why the reason you can't use it and also several moderate speed, but 200 nanosecond you see here the is the transfer going on.
Chris Damerell: And after hundred and 59 so you've got the whole signal now for our purposes that irc that's absolutely wonderful from any.
Chris Damerell: You know llc applications that would be useless, so it just happens to be a good match for the IOC or cq tracker with this.
Chris Damerell: Time integration during the during the bench train and that.
Chris Damerell: What you're seeing here this beautiful transfer is four pixels that are five or 10 microns insights and we talked about 50 microns So are we talking nonsense, so this is a new development from constant he didn't do for us, he did this for X Ray.
Chris Damerell: telescope applications where they've got 40 micro and when 40 micron pixels they can perfectly well do 50 by 50 where they managed to do the full.
Chris Damerell: transfer, you see, he says, I think he says, and we hear about.
Chris Damerell: yeah conventional charged stretcher doesn't work for about 10 right zero lateral electric field to just sits around and the problem is.
Chris Damerell: If you've got tiny with a Min I signals a small signal you got tiny irregularities which you will always have.
Chris Damerell: In the potential then it's the so called potential pocket and the signal can just sit there and never going to get to the APP so you need something so he's installed doping gradients which provide them a sufficient.
Chris Damerell: Just field within the pin photo diet and he can still achieve less than hundred and second charge transfer for these large pixels.
Chris Damerell: And the charge so is initially drifted into the five micron sub volume and then, when you do the.
Chris Damerell: The transfer gate it's only a very local charges or very local and it still takes about a microsecond to get the whole thing from such a large pixel but, in our case.
Chris Damerell: You know, we are, we are talking about a situation where we integrate.
Chris Damerell: The signal through the bunch train, which is a millisecond and then read it out over 200 milliseconds so all of this is.
Chris Damerell: instantaneous as far as we're concerned there's absolutely no problem and constant gave a talk of this is that said CMOs group and slack.
Chris Damerell: and constantly gave a talk on this reason, so you can you can look at the indigo for that, for the for the details of the slides it's absolutely wonderful work so so the thing is that that what we want to do we're talking about 50 each of these as a 50 micron pixel been further died.
Chris Damerell: But we don't want to completely deplete as they do for X rays, because if you do that, you know.
Chris Damerell: it'll be almost binary right you get most of your signal in one pixel and then you're going to certainly not going to get to a good.
Chris Damerell: tracking precision, so how can we do that well the suggestion is that we'd have something like 50 microns.
Chris Damerell: EPI material on a bet on a highly dope substrate so you've got a reflective layer here when it comes to diffusion and that we would deplete probably only 10 microns and.
Chris Damerell: And and, therefore, or even for normal incidents, a lot of the signal is going to diverse significant amount of signal is going to diffuse out of the pixel and, therefore, you will get us, you know useful centroid.
Chris Damerell: which will we get five microns we we don't know we've never seen the great news is, is why I gave this talk, last week the op amp D people is Daniel Heinz Heinz who is one of the leaders of the Olympic square development that's a generic.
Chris Damerell: toolkit for pixel studies in particle physics, is absolutely wonderful work that they've done is.
Chris Damerell: is now an Oxford and he's very enthusiastic to do this is actually privately quite convinced it's going to work but also using the time PICs for chips, which are just coming out.
Chris Damerell: As the readership he's thinking to do an experimental test as well, and with partial depletion to to see how will this will work so that'll be a wonderful development and hopefully that'll all take place in the.
Chris Damerell: In the months ahead in the simulation, of course, will vary these parameters and see how well we can do there's one other thing about this.
Chris Damerell: and
Chris Damerell: yeah I just mentioned, that that Valentina Cairo, who is a mosque effeminate slack is keen to study the overall.
Chris Damerell: performance of the tracking system, but you can't start, because at the moment you can't put in the five microns what the right number is really.
Chris Damerell: Okay, this is just a little cautionary thing from suit on he was also relevant postdoc in the early days and and I don't know if you all know, the paper.
Chris Damerell: It was a silicon people by Hans pixel there's a wonderful reviews of modern physics paper, in which he really was in detail at the actual details of the ionization process.
Chris Damerell: from ionizing particles and what happens is that the primary process is the generation of 17 ev plasma phones and SOFA very thin layers you can see the quantities nature of that and he is, if you would imagine that this is a simulation.
Chris Damerell: One micron thick silicon detector, this is what you get from Orlando distribution, and this is what you get in practice, so this is.
Chris Damerell: done even got zero it can go through without losing any energy at all because it's quantifies and here you've got a one plus one or two players on and so on, and.
Chris Damerell: So you build up a very broad distribution extending down to.
Chris Damerell: pretty much zero energy D position at more realistically here, you see one GB me on simulated by suit on of 10 microns up to 35 micron seven to 10 micro and you see abroad, and it goes down to a very low level, so when you.
Chris Damerell: consider your track going through your partially depleted detector you better take this sort of thing into account, because otherwise you will.
Chris Damerell: You know, underestimate the spread and, of course, the more spread you've got the more irregularity you've got in the charts distribution along the track the worst the.
Chris Damerell: centroid in will work and they've already seen this in atlanta's cover called pseudo is a member of the address collaboration and.
Chris Damerell: For oblique tracks in their vertex in the pixel vertex detector they've already seen these effects and answered on the simulated them all.
Chris Damerell: I won't say anything about the readout it's rather conventional rolling shutter and it or we can we can read the whole thing up in the 200 milliseconds between the bunch trains very.
Chris Damerell: Naturally way and that's why we can get to such a low noise and and.
Chris Damerell: And digitization probably six bits what people say why do you want that well as well as to do the centroid he is also the fact that, as I showed you in that the FCC to example and we had digitized and read out there which.
Chris Damerell: allowed one to measure the energy of all those X rays, which is very interesting and very informative in terms of what's coming out of the beanpot so.
Chris Damerell: So I i'm personally very much in favor of measuring the amplitude of the of your of your signals in a pixel detector for reasons that you might not think about at the beginning.
Chris Damerell: Okay um few words running out of time, few words about the mechanical design, we want to use obviously much less material than the.
Chris Damerell: microchips had we talking about long letters made from what you saw the size of the thing four to 8% silicon carbide phone chosen because it's such a good thermal match to silicon.
Chris Damerell: The idea is that each barrel will be self supporting so there's these long.
Chris Damerell: Support means running the whole length of the tracker which would be very flexible and horrible mechanically but along the length, we put a little links phone links, or both, but together adhesive to minimize material.
Chris Damerell: And about one centimeter deep in the in the view of the paper and at about set 40 centimeters and that really stabilizes the whole thing.
Chris Damerell: Let me just show you this, but this is very.
Chris Damerell: To understand what this is yeah this is showing you okay here if you made a continuous form, so the type that i'm talking about what would you get this would be the distortion of the end CAP, and this is distortion of the barrel, but.
Chris Damerell: The maximum deflection 10 microns, so this is put on a huge year, so it would be just fine this is gravitational with were loaded with the detectors and all the rest of it so that's the.
Chris Damerell: gravitational effect gravitational sag completely acceptable if you did what we just saw but you didn't put any links in between, then it is genuinely horrible.
Chris Damerell: 20 millimeters so these, these are the guys at the bottom or you're saying by 20 millimeters enter the top two so absolutely horrible.
Chris Damerell: But if you put in these little links, then you come down to 20 microns not as good as that but still, you know perfectly acceptable as long as it's stable.
Chris Damerell: And so that's the general thinking about the mechanics, which is a lot of work to be done on that so conclusions on the pixel tracker.
Chris Damerell: is a powerful physics case for a low mass gaskell pixel tracker combining highly pixelated bows and end caps time integrating During the lunch train.
Chris Damerell: single bunch time stamping for every track, but they're here, I make the.
Chris Damerell: comment about possibility of combining that with a rich system i'll just flash a couple of slides to show what's going on there during Barber is is.
Chris Damerell: And anthony's has been very helpful with with thinking about that so that's work which is going well, again in the service versus the sensors.
Chris Damerell: And we believe that the Info denied pixels or will match the needs the partial depleted variant has to be checked by simulation and experiment.
Chris Damerell: there's always room for new ideas and I just mentioned, this again as just a flasher side there's even more advanced ideas of stack devices.
Chris Damerell: Which haven't received much attention in Europe, but they've been studied elsewhere, so I just mentioned them to be be aware of it.
Chris Damerell: which could I don't think we're going to need anything like this for our tracker, but I just mentioned, this is this is going on for other applications so i'll just show you a couple of slides, this is the talk that Valentina gave.
Chris Damerell: You just a week ago in the fcs FCC physics workshop Liverpool Liverpool but virtual, and so this is the team she calls it, the strange team because it's not only looking at the strange.
Chris Damerell: jets but also the fact that two of the members of the team Jerry and I are in our octogenarians which is rather unusual.
Chris Damerell: by God, but Jerry is fantastic and so he has been looking at the design of a chair uncovering engineering system he's got 25 centimeters thick here, he thinks he may be able to get that down to like 15.
Chris Damerell: Central here's the the for 2020 gv crayons and pilots, these are the Rings beautifully separated, you need to do the discrimination for for the strange jets from about eight to about 30 gv so it has to be guests.
Chris Damerell: Rich type gaseous rich type system and that's what he's a great expert on so he's written already a big paper for snowmass on that Sunday.
Chris Damerell: And the other thing I was going to just mentioned, is this business about.
Chris Damerell: wafer stacking so here, you see work going on at brookhaven, this is an x Ray application you've got a sensor layer, which is about 300 micron stick.
Chris Damerell: you've got two other layers which are each about 15 microns thick waiver bonded together and so you've got analog and digital behind, and you can do phenomenal.
Chris Damerell: Processing with such a thing he could never do in a monolithic and then you've also got tsp he's giving you to.
Chris Damerell: bump bond on the backs of these these things can be for side battle and so on, so that's wonderful work there's probably even more exciting work going on between Sony and Rican takaki had three for my.
Chris Damerell: career article I tried to talk to him and he was so polite but he wouldn't he said he cannot say where, because of the.
Chris Damerell: nda with Sony but it's very easy to see how this goes, if you look what they did for visible light imaging when here's one of the Sony chips, you know you've got your this is this is 7.8 microns and there's and there's another one below and here you've got your micro lens your your.
Chris Damerell: Deep trends isolation, these are these pixels eyes about one micron and deep turns isolation to maintain the optical and then.
Chris Damerell: The the analog processing in on the same chips I get this very good noise performance and then off off the picture you've got.
Chris Damerell: tears of ease and sondra go down to this image processing to below, so this is amazing stuff and hopefully eventually we'll see the sort of thing also for particle physics applications, but as I don't think we need it for for irc So what are the overall conclusions, then.
Chris Damerell: Maybe our Japanese friends will work a miracle and get IOC off the ground, the strong Asian European North American participation that's what's needed.
Chris Damerell: not sure about European and if not, maybe the USA will execute and some other regions will join in doesn't have to be everybody.
Chris Damerell: In either case, the detector groups have at their disposal exciting ideas for tracking and political idea and so needs to be a very interesting.
Chris Damerell: Development of the detectors, for that is by no means people are way too wet irc is being shovel ready is nothing shall read about it this heck of a lot of work to be done, and despite.
Chris Damerell: decades of development and other options, I don't want to point the finger, but I would say tpc isn't just chambers, with their thick and plates.
Chris Damerell: are unlikely to succeed, it pains me to see that these things, despite our review in 2008 are still going strong I mean, in the sense of R amp D and.
Chris Damerell: Students and all the rest of it, I mean I think that's just not the way it's going to go in the time, so I think it will be.
Chris Damerell: It will be pixels but I can't really prevent obviously so some basic truth just my opinion.
Chris Damerell: Energy frontier is not going to go away, you can do what you like, with FCC but it's not going to get there circular clusters can't get there.
Chris Damerell: and have the TV scale when needs minimal material in the track over the full angular range, these are just sort of voters.
Chris Damerell: A P ID system for sj and maybe a game changer for beyond selling model physics and we don't know can't prove it and those who don't want to rock the boat say you're rooted we don't need to do with.
Chris Damerell: With a strange party identification, but that could be.
Chris Damerell: Another failure they've been quite a few fights and below the you may really need it, we don't know I just in a completely different context, of course, Richard fineman.
Chris Damerell: sin nature cannot be fooled and that's certainly true here, but of course we don't really know what nature nature's hiking so there's not a very.
Chris Damerell: Important statement so that's it Oh, this is just.
Chris Damerell: A little thing to show MIT I do if you saw this but they've a new material stronger than steel and lighters plastics, are you drop your.
Chris Damerell: mobile phone on the payment and then you can even hit it with a hammer, is not not that so that's just an indication that material scientists also is also advancing so.
Chris Damerell: That I think is all that yeah so I finished, thank you very much, so i'll stop share.
Ivana Hristova - STFC UKRI: Thank you very much, Chris for this great talk.