STFC-RAL-CR03 R61: Yeah, it's one minute past, so let's start.
STFC-RAL-CR03 R61: It's a pleasure to welcome Aparizio Paolo.
STFC-RAL-CR03 R61: Hoppies came in person.
STFC-RAL-CR03 R61: I think that's our first SCC 79, the first thing. So thank you very much for coming. A short introduction.
STFC-RAL-CR03 R61: It's a shortened version of what we have on the legal page. Yeah, so for Britt, you began a research…
STFC-RAL-CR03 R61: his research career in the Alephic collaboration at LAMP, working on electroly precision measurements and big wall physics.
STFC-RAL-CR03 R61: Including the first determination of the number of live neutrino species, which we now make branded, and the precise measurement of the branching ratio of the bottom tick marks.
STFC-RAL-CR03 R61: He contributed to the early development of the verbal rotational wave interferometer, designing and testing the suspension system for seismic noise attention.
STFC-RAL-CR03 R61: And, as you imagine, this experience broadened his expertise in precision instrumentation and mechanical design.
STFC-RAL-CR03 R61: Since 1998, he has played a leading role in the CMS experiment at LHC, coordinating the construction and commissioning of the silicon truck.
STFC-RAL-CR03 R61: At the moment, he's an experimental physicist at INFM. He's a
STFC-RAL-CR03 R61: With over 30 years of experience in high energy physics and detective technology. He's currently leading the INFN
STFC-RAL-CR03 R61: participation in the FCC experiment, so-called IDEA.
STFC-RAL-CR03 R61: and… and collating the machine detector interface in the FCC overall FCC.
STFC-RAL-CR03 R61: EE overall project. So, alongside with his research, he has also a strong commitment to education and mentoring, and he is teaching university courses in experimental physics instrumentation, thermodynamics, and has supervised numerous
STFC-RAL-CR03 R61: PhDs and master's theses for one, prizes as well. So, over to you.
STFC-RAL-CR03 R61: I'm really pleased to stay here this morning and, share with you Maddie.
STFC-RAL-CR03 R61: Hello.
STFC-RAL-CR03 R61: Don't spot what would be the challenges for building a tractor, especially
STFC-RAL-CR03 R61: within this very targeted area of the FCCB.
STFC-RAL-CR03 R61: So, how this seminar, grew up, you may remember that,
STFC-RAL-CR03 R61: A couple of weeks ago, something like that, Chris Daniel, who's not here today, unfortunately, was giving a seminar about, their experience at Slack, in the SLV detector, about, all the backgrounds that they sold, and, this was, inspirational to us to make,
STFC-RAL-CR03 R61: Progresses in understanding whether what we'll be seeing will be the same size or different.
STFC-RAL-CR03 R61: As I will show you in a minute, this is a quite long presentation, don't read all the slides, these are put for your convenience.
STFC-RAL-CR03 R61: But this is a bulk of work which has been put forward in the next, in the previous years by a lot of people, and it's summarized in these two documents. The first one is the,
STFC-RAL-CR03 R61: taking an instrument in MVJ, which is a tight bulky, document, about 60 pages.
STFC-RAL-CR03 R61: all what you have to know about MDI and the FCCE. And second one is the feasibility Status Report, Volume 1, which is dealing about physics experiments and vectors.
STFC-RAL-CR03 R61: Just a few about 5 advertisements. If you really are interested to join our activities, please subscribe to this mailing list, and you can… are very welcome to
STFC-RAL-CR03 R61: Stay, along with us.
STFC-RAL-CR03 R61: Oh, sorry, so next. So the main point I wish to address in response to Chris…
STFC-RAL-CR03 R61: seminar, are summarized here. Throughout the presentation, I will tackle most of these points, all of his points. In particular, the claims that he was doing about,
STFC-RAL-CR03 R61: the naive, let's say, extrapolation from the SLD experience towards the FCC woman.
STFC-RAL-CR03 R61: It was quite strong in saying that the, evolution of these backgrounds should be following only the current dependents, but it's actually not that
STFC-RAL-CR03 R61: We know that processing angle, detector fields, time integration time of the vertex detectors would also matter, and I will show you how. In particular, the integration time at FCCE is a thousand times shorter.
STFC-RAL-CR03 R61: Than the SLV.
STFC-RAL-CR03 R61: The occupancy that it was claiming for us to reach.
STFC-RAL-CR03 R61: 1.5% would be dramatic for us, of course. And,
STFC-RAL-CR03 R61: As I will show you, it's automatically smaller than that.
STFC-RAL-CR03 R61: Air pooling, it was having some doubts. We're approaching to, to make it clear, and, as I will show you in a few minutes, we are working on that and demonstrating that that will be fixable.
STFC-RAL-CR03 R61: Another thing that he was worried about was whether or not, in our simulation, we were switching on, ozitron annihilation.
STFC-RAL-CR03 R61: Of course, everybody can switch on or off.
STFC-RAL-CR03 R61: the plagues in Sergeant, or we were brave enough not to. And,
STFC-RAL-CR03 R61: Finally, I will try to convince you that our simulations that we've done that so far, of course, by far.
STFC-RAL-CR03 R61: Not complete, but still, they are much…
STFC-RAL-CR03 R61: less younger than it was attributed by Chris, so we are a little bit more ahead with respect to our infancy. And our community is very well open to everybody who wishes to contribute and will be joining us.
STFC-RAL-CR03 R61: So, I'm flashing this. I suppose that everybody knows the layout of the FCC, which eventually would be happening around CERN. You can see CERN is located
STFC-RAL-CR03 R61: Over there, and, we are down to, NC, and this is 100 kilometers, almost 100 kilometers long tunnel, 90 kilometers long, and as an LHC, it was…
STFC-RAL-CR03 R61: or XSS, or OLED, the two, machines would be built exactly on the same, in the same location, in the same tunnel. It features, FCC integrated program, first stage with FCC EE, so in passing collisions.
STFC-RAL-CR03 R61: Followed, eventually, by a proton-proton collider.
STFC-RAL-CR03 R61: Which is, yet to be, lifted.
STFC-RAL-CR03 R61: Oh, the project next to the… that is.
STFC-RAL-CR03 R61: So, in a nutshell, this is the integrated luminosity… these are the satanic luminosity that, is,
STFC-RAL-CR03 R61: We are aiming to, so it's, lap one statist will be given in a few minutes. We have a TerraZ,
STFC-RAL-CR03 R61: factory, followed by two other energies for the W and ZH.
STFC-RAL-CR03 R61: And eventually, a TT bar scan between 350 and 365 GB. If you compare the Luminality Z with the linear fixed factories, you can appreciate how much
STFC-RAL-CR03 R61: Luminowski would then get more, even at the same time.
STFC-RAL-CR03 R61: This is the, very good table, which shows about, 10 Z1, so we'll, end up with about, more than 10 to the transit.
STFC-RAL-CR03 R61: I mean, this is fascinating for those who are at lab. Several hundred millions of W, whereas, millions of, very clean environment.
STFC-RAL-CR03 R61: wise, egg explosions, and few minutes, of dark properties.
STFC-RAL-CR03 R61: And if you manage to collect such high statistics, this is the comparison of FCC with respect to Belto, which is yet to be
STFC-RAL-CR03 R61: Coming in the next, 50, 15 years from now.
STFC-RAL-CR03 R61: So, we are powered by a lot amount, and we're producing quite a lot of,
STFC-RAL-CR03 R61: Let's say, medicines and virus, which will not be able to produce at that time.
STFC-RAL-CR03 R61: So, the main parameters at the interaction region, these are summarized here, for different beam images. We have a beam crossing angle of, 30 milligrams in XY, and crab waste optics, I will come in green.
STFC-RAL-CR03 R61: So, this crossing, and with nanobeams, will allow to give us quite a lot of luminosity, and the term is the luminous region sites, both in X and in Y.
STFC-RAL-CR03 R61: By design, the machine, is, has a flat top of 50 megawatt, per VIN, simple corrugation, so we cannot exceed that, and that determines the maximum lignos… the maximum VIN current.
STFC-RAL-CR03 R61: And therefore, this time of luminosity, which is also determining the interaction frequency and the size of the beam in Z.
STFC-RAL-CR03 R61: The first machine element is quite inside the detector, the detectors being about 12 meters long. The first element is about 2.2 meters from the attraction point, so we have, likewise, bed to, all the detector, all the machine elements inside.
STFC-RAL-CR03 R61: And the maximum field, in order not to decrease the luminosity at that set, is… should not exceed 2 tesla. Now we have, possibly some other possibility to go to 2.5 Tesla. This limit can be overcome for the higher energies, so we can even go to 3 tesla.
STFC-RAL-CR03 R61: I'm being dumb. Could you just clarify what the 50 megawatts is? Is that… is that synchrotron radiation? It's secret radiation power around… around the entire, machine.
STFC-RAL-CR03 R61: So, as we collide, the beams are colliding with this so-called nano beam scheme, so we squeeze the beam such that the Y position is very, very small, and we have a large horizontal crossing angle.
STFC-RAL-CR03 R61: In such a way, we have a small instantaneous collision area, which is basically the X
STFC-RAL-CR03 R61: This is XZ, the X, sigma divided by the crossing angle, and due to these, cutway sextopoles, we can adjust the beta star, which is inversion in proportional to the luminosity.
STFC-RAL-CR03 R61: Such that for the entire region of collision, it is kept at its minimum. So therefore, we cannot… we do not suffer of the so-called hourglass effect.
STFC-RAL-CR03 R61: Which eventually is limiting, all the other collisions, which is not adopting such a… such a quick waste scheme.
STFC-RAL-CR03 R61: The main drive for the vertex detectors is obvious. I mean, we have to deal with Higgs physics and the B physics. The Higgs decay is 85% in AV porcs, and therefore our vertex detector needs to be… isn't tied in the B and trunk forks from the rest.
STFC-RAL-CR03 R61: And therefore, we need to have a very high precision, point resolution, and as low as possible multiple scheduling.
STFC-RAL-CR03 R61: These are the, replied cello mass and high granularity purpose detectors, with heat efficiencies above 99%.
STFC-RAL-CR03 R61: a quite large angle of coverage, which is, I will show you in a minute, is limited by the VIN pipe, services, a pipe resolution of the order of 3 microns, and material budget per layer, which is smaller than 2 per million.
STFC-RAL-CR03 R61: Probably the left.
STFC-RAL-CR03 R61: All these requirements are,
STFC-RAL-CR03 R61: summarizing the slide. On top of that, since we have to monitor on the Linux team, having a quite small, let's say.
STFC-RAL-CR03 R61: order of, a fraction of a mil, we need to, make the least as possible damage to the Lipinovsky, monitor in front, which is located
STFC-RAL-CR03 R61: a few meters away, one meter away from the interaction point, so we cannot go really down in the acceptance in order not to, jeopardize the, energy measurement and the position measurement.
STFC-RAL-CR03 R61: The other point is that the calorimeter needs to have the highest possible electricity, and therefore, we have…
STFC-RAL-CR03 R61: quite constraints on the compensating cryostat and screening solid cryostat not to be too much interfering with the limiters in the forward direction. I do a sketch of the Lumica, which is about 1 meters away from the interaction point, then we are compensating cryostat.
STFC-RAL-CR03 R61: which gives a counterbalancing in magnetic field in order to, zero the integral of the magnetic field as B.
STFC-RAL-CR03 R61: And then we have screen soil at Cryostat, which is screening, these, planet ports. There are three…
STFC-RAL-CR03 R61: segments in particles close to the attraction point. And we are ending up here at a few meters, well inside the… I mean, if QC1, the first kiosks, is well inside the detector, as I said before.
STFC-RAL-CR03 R61: This is a three-dimensional view of the current vertex detector, one of the most engineered layouts of the vertex detector, which features an inner vertex, which is located very close to the main point.
STFC-RAL-CR03 R61: two bottom layers and three disks in either side, which are followed by the luminosity detector, and then when the wide beam, I mean, when the beam pipe diverges into the two beams, to the lead pipes, we put the mobile connection, and the first magnetic element is the two
STFC-RAL-CR03 R61: But to read the beam pipe is this funny shape, because we do not… I mean, the,
STFC-RAL-CR03 R61: Luminosity detector, sorry, luminosity detector is centered around the exiting.
STFC-RAL-CR03 R61: V?
STFC-RAL-CR03 R61: And therefore, the spine shape shows that, it's not centric. I mean, the cooling manifolds of the outermost beam pipe, the lateral beam pipes, are not centered around the
STFC-RAL-CR03 R61: There are cooling manifolds here that have been shown in this picture here. It prevents us to go lower in angle, and therefore we can reach only 0.99 of active
STFC-RAL-CR03 R61: And you can see that, due to the
STFC-RAL-CR03 R61: weight fields induced by the beam. We had to cool the beam pipe because of… we get 50 watts at… order of 50 watts at the Z of power to be dissipated along this central beam pipe, and more than 170 in the lateral beam pipe. So we have a liquid paraffin flow.
STFC-RAL-CR03 R61: B5?
STFC-RAL-CR03 R61: And, water-cooled types, therefore.
STFC-RAL-CR03 R61: just to appreciate the difference with respect to SLD, interaction region. They had, the several masks.
STFC-RAL-CR03 R61: And we have head-on collisions. Their radius is, 25 millimeters radius. Our VIN type is 10 millimeters radius. We have a 0.6 Tesla, so another field.
STFC-RAL-CR03 R61: And we have two Teslas on that field. You can appreciate that the first element of the, I mean, bulky structure here, which is the NOSI detector, is a 1 meter. Yeah, they have some shielding here.
STFC-RAL-CR03 R61: The opening is quite bigger than… it's twice as bigger than us, so whatever punches back, it has a bigger acceptance to go enter, like, into the practice connector.
STFC-RAL-CR03 R61: Technologies to be lightweight vertex detectors are these called monolithic pixel detectors, also known as maps.
STFC-RAL-CR03 R61: In which electronics is built on top of the same, sensor, fully integrated. They can reach even thicknesses of over 50 microns.
STFC-RAL-CR03 R61: And with very, very low, power densities. We can, have, some
STFC-RAL-CR03 R61: say, possibilities, depending on fabric, to have also stitching at 12 inches, so it's 25 centimeters long object in a row, or a but, say, stitch two sensors together.
STFC-RAL-CR03 R61: There are several foundries that are currently providing this technology, and one group in the ECFARD3, working group, which is addressing them, R&D. Yet to be established, you can even
STFC-RAL-CR03 R61: builds, let's say, some completely different detectors, also pairing with a full silicon photonics or a full other, let's say, digital logic on top of it, a few microns, overlay it. Yeah, this is yet to be, solved.
STFC-RAL-CR03 R61: And of course, the gap here is to trim the spatial resolution versus timing, but power and the circulation resistance. This is the baseline of the vertex detector. As I've showed you before, we have an inner vertex based on this cardiac project, which I will show you in a minute, of modules of 25 and 25.
STFC-RAL-CR03 R61: Square microns, 3 barrel layers, at the…
STFC-RAL-CR03 R61: 1.4 centimeters, 24 centimeters… yeah, sorry, 1.3 centimeters, 2.4 centimeters, and 35 centimeters, followed by, let's say, more or less traditional Alice-like structures in the bar and in the front.
STFC-RAL-CR03 R61: So, this is the vertex layout. The total thickness per layer is, in this arrangement, about a quarter of a percent of additional length.
STFC-RAL-CR03 R61: Out of which the carbon fiber drives the material part. So you can see, you can appreciate layer 1, layer 2, and layer 3 arrangement in counter-rotating a green wheel, or,
STFC-RAL-CR03 R61: lampshade, arrangements. This is the power anticipated, order of, over about 100, watts altogether.
STFC-RAL-CR03 R61: For an active area, which is, everybody's dense, huh? So we have, traditional, let's say, layout, I would say.
STFC-RAL-CR03 R61: The sensors are this, Kagan sensor, so, which, is an Italian, RMD,
STFC-RAL-CR03 R61: based by, on using L-Funter process, under 10 nanometers. We can, have several thicknesses, down to, let's say, all about 15 microns, 40 microns.
STFC-RAL-CR03 R61: activation. And, currently we have, measured, this, this, 6, 7
STFC-RAL-CR03 R61: modules to be able to go to order of 50 milligawatts or even less per square centimeter power density, and the data without is able to cope with order of 100 megabits per square centimeter by design.
STFC-RAL-CR03 R61: If there are other, let's say, processes that, people are, currently using, as the one used for the Alice, upgrade, and in which the epidural can, like.
STFC-RAL-CR03 R61: Just to make sure that we also have a look at what Chris said, I mean, the branch crossing rate at the FC would be 40 MHz, whereas the crossing rate at SLC was 100… more than 100Hz.
STFC-RAL-CR03 R61: The vertex integration time is much, much different. At SLD was about 200 milliseconds.
STFC-RAL-CR03 R61: So they were integrating about, 30 bunch processings. And, despite of the larger,
STFC-RAL-CR03 R61: frequency at MCCE, given that there will be order of a microsecond, we'll be integrating more or less the same number of bunches. So, we are not at 5 disrespect to what has been done in the past.
STFC-RAL-CR03 R61: The material budget is quite dominated by the VIN pipe due to this active cooling, and you can see here that at 90 degrees incidence angle, we have a, let's say, 70%… 0.7% over additional length due to the VIN pipe.
STFC-RAL-CR03 R61: Followed by the inertex detector. Already with this arrangement, we can go order of 1% at the normal angle.
STFC-RAL-CR03 R61: This is the entire, let's say, the complete immocortex detector, which is only doubling the advancement in the central region.
STFC-RAL-CR03 R61: You can even go lighter, like ITS3, using band detectors. There are two flavors which are understudied by now, and in which case, you can really appreciate quite a lot of, let's say, differences in material composition, and you can go down to a fraction, or a percent, or additionally.
STFC-RAL-CR03 R61: By also increasing the number of layers from 3 to 4.
STFC-RAL-CR03 R61: And of course, the, improvement can be seen here, but it's not that much
STFC-RAL-CR03 R61: Appreciable because of, the first
STFC-RAL-CR03 R61: low PT particles, low-momentum particles, because of the impact being so heavy. So, they've not gained that much, I would say.
STFC-RAL-CR03 R61: Air cooling, we are about there. In Pisa, we have a setup, and, we put some of the smoke-up saves inside our air cooling,
STFC-RAL-CR03 R61: machinery, and we've been measuring that we are able to pull it down, or down to, I mean, having a perfect, almost perfect, power dissipation between, along the stave and its removal.
STFC-RAL-CR03 R61: The temperature difference between inlet and outlet is observed of 2 degrees Celsius.
STFC-RAL-CR03 R61: with, air cooling of the order of, I mean, the entrance quite big, order of, 20 meters per second, but in the middle, very, very low, order of 2 meters per second.
STFC-RAL-CR03 R61: So we can, assume that, well, this is a first stage, of course, I mean, it will be followed by other measurements. From the simulations, the vibrations which are expired are of the order of one-half microns, and this will be tested experimentally in Siem.
STFC-RAL-CR03 R61: We had to mount… to, mount the Luminosity, monitor inside the so-called support tube, which is supporting not only the beam pipe and the workers, but also the, Luminosity monitor. This is a sandwich of, silicon and timestamp.
STFC-RAL-CR03 R61: elements, and you can appreciate, that it's centered around the upper beam pipe. This is the outer beam pipe, which is the incoming beam.
STFC-RAL-CR03 R61: And it's placed quite in a crowded area, where there are services here that needs to have it, and for cables, all on the back.
STFC-RAL-CR03 R61: Let me now go and describe to you what we've been doing in estimated bands at FCC. You can see that I've divided the luminosity… I mean, the backgrounds in two big classes, luminosity bags to charge synchronous.
STFC-RAL-CR03 R61: With the interaction, and can only be discriminated at trigger level, if you want to suppress them, because they are exactly coming from the traction point, and it's a luminosity, proportionally, luminosity, proportional.
STFC-RAL-CR03 R61: There are two big, let's say, classes, the Australian potential and spent being.
STFC-RAL-CR03 R61: Out of which the Korean plus and minus percreation is found in one, and for that, we'll be using a generic simulation.
STFC-RAL-CR03 R61: Running BABA, which is a process that… in which very much cross-section, especially at the very forward, these photons are hitting the quadrupes and heating them up eventually, so we have to be careful to shield them. And these have been benchmarked with lab data using BB brand,
STFC-RAL-CR03 R61: Cool.
STFC-RAL-CR03 R61: Then there are single beam effects, in which most of these effects can be mitigated using collimeters, or feedings, except for those which are really producing detection points. So, in some cases, you cannot make much more.
STFC-RAL-CR03 R61: Out of which synchrotron radiation is the biggest one, beam gas, thermal photon, two ship, which is affecting mostly low-energy wings, such as SuperKV, injection backgrounds, we know very well that this is a problem for Supergat V, and beam model losses.
STFC-RAL-CR03 R61: Basically, a full set of pollination sessions have been studied for each one of the optics that will be used, and all whatever residual losses are being trapped into the detectors for occupancy and analytics.
STFC-RAL-CR03 R61: Going to the beam-induced backgrounds, this is the status. We are not letting that infancy. We just had several of those, first operation and tracking levels done inside of the factors. You can appreciate that some of those are really, really nasty.
STFC-RAL-CR03 R61: The work in progress is mostly for the symptom radiation, super effective sudden wind loss events, even we did not expect.
STFC-RAL-CR03 R61: such a thing to occur at MCCE, injection failure, which could happen for MCCE, and those which are not started are, let's say, less problematic, thermopos, where
STFC-RAL-CR03 R61: We do expect some effects. The extraction failure is really a problem, and other possible failures that, of course, misunderstood.
STFC-RAL-CR03 R61: just to show you that, the, XSUT releasing, simulation has been benchmarked using, the SuperTechB data.
STFC-RAL-CR03 R61: These are the, measurement point, dots, overlayed with the predictions, and therefore, we are quite confident that we can, say.
STFC-RAL-CR03 R61: Use this simulation to estimate such patterns.
STFC-RAL-CR03 R61: We have a full machinery in place, which have, production at the level of the accelerator of these dragons, traced back at the boundaries of the detectors, and then using FUCA, and then using GENS for, generating these particles inside of it.
STFC-RAL-CR03 R61: We have a full modelization of the interaction region, which is based on the CAD models, so we insert directly from the CAB, the models inside, sort of, CAB drawings, the models in general.
STFC-RAL-CR03 R61: And then, we imported GL models, for this, interaction region beep pipes, the magnets, for which we have simple interior model that is quite accurate in terms of geometry. For the gray officer, which needs yet to be designed, we have, simple grass, but we have… and for the synchronization, we have a mask, which is appreciated here, at 2.1 meters away from traction.
STFC-RAL-CR03 R61: This is the FUCA model, which is, using a completely different geometry, set.
STFC-RAL-CR03 R61: But using exactly the same, drawings from the CAD, importing a different, let's say, framework, you know that Fluque and JAMT, not, Tokichan. But we do have these two kind of, let's say, fully retained simulations.
STFC-RAL-CR03 R61: going to the bulk of the debate, being strong in FCCE, this is basically, equine pre-creation. So you, make a pair of electrons and polygon
STFC-RAL-CR03 R61: With very low PT, order of a few MAB in PT, which are eventually, showering, inside of the detector.
STFC-RAL-CR03 R61: So, either directly or by scattering, especially the photons coming from the emulation of the positrons, emulate in a few nanoseconds in bulky structures, mostly in the forward region, and some of these photons can bounce back into the vertex detectors, making also, say.
STFC-RAL-CR03 R61: Conference scattering, or…
STFC-RAL-CR03 R61: energy and the position, which are different. You can appreciate that this, I mean, beam style is quite peaked in a forward direction. This is exactly, more or less, where the beam
STFC-RAL-CR03 R61: crossing is… this is the detector reference frame, the angle reference frame. So this is where the beam is gone. So most of these particles are over-directed.
STFC-RAL-CR03 R61: It divides much more quickly. And if you overlay the vertex detector acceptance due to the magnetic field of 2 Tesla, there's a minimum PT.
STFC-RAL-CR03 R61: that needs to be there in order to reach the black test detector, and in the undercover, you can see that these part of the… of these particles can
STFC-RAL-CR03 R61: go inside the 30 seconds. You can even appreciate that the peak in the energy, sorry about that, I didn't put the correct label here, but it is 511 kebab,
STFC-RAL-CR03 R61: position annihilation peak. So these are photons produced inside our simulation, which is, as we see them, and you can appreciate that, they are
STFC-RAL-CR03 R61: Much less than that in the order of… bringing inside the texture.
STFC-RAL-CR03 R61: So, main differences between SLD and FCC in this respect are many. First of all, currents were different. I mean, of course, SLC had very lower currents with respect to FCC.
STFC-RAL-CR03 R61: But the B profiles and the crossing angles were completely different. The B profiles, I mean, X…
STFC-RAL-CR03 R61: as I showed you before, are, quite different, and the SLC had, head-on collisions.
STFC-RAL-CR03 R61: So we ran the linear peak using SLC parameters, and we compared the number of particles out of this linear peak, which are coming off the simulation.
STFC-RAL-CR03 R61: So we have more or less the same number of particles, except… I mean, per bunch crossing. So this, of course, bunch crossing rate is different, but each cross, you just have on the order of 1,500, 2,000 particles per branch crossing produced.
STFC-RAL-CR03 R61: If we were running the SLC with the same currents of FCCE, we would have gotten a factor of 30 more particles.
STFC-RAL-CR03 R61: Because of, the currents.
STFC-RAL-CR03 R61: And Chris was right. But if we were using the same crossing angle as we do have at CCE, at SNC, we would have gotten 40 times lower.
STFC-RAL-CR03 R61: particles. So the two parts balance.
STFC-RAL-CR03 R61: To some extent, okay? So, this needs to be kept in mind. So it's not only the current which happens, but also the crossing.
STFC-RAL-CR03 R61: There you go.
STFC-RAL-CR03 R61: And the other point, is that we have been quite generous, because we…
STFC-RAL-CR03 R61: I mean, for the moment, we are currently having now Not changing that in the…
STFC-RAL-CR03 R61: In the final stage, a clusterizer, which is mimicking the electronics response of the data. Eventually, we will have it for the next round. But we assume a cluster size of 5, so every single kit is multiplied by 5 in our simulation.
STFC-RAL-CR03 R61: 5, let's say, pixels. And we applied a fudge factor of 3 in order to have a safety factor, in order to make sure that the electronics were, let's say, in a position to be, let's say, designed.
STFC-RAL-CR03 R61: And, we also had a cut every minute, of 500 electrons as a threshold, which corresponds about to get
STFC-RAL-CR03 R61: Okay? With that in mind, we end up with something like of the order of 200 megans per square centimeter, which
STFC-RAL-CR03 R61: corresponds to an frequency of 5-10 to the minus 5. It's not 1.5%, as Chris was,
STFC-RAL-CR03 R61: same. Nevertheless, this is quite big in terms of batteries, because you have to multiply by some
STFC-RAL-CR03 R61: a known number of bits that you have to extract out of each pixel, and you can easily end up all the order of 100 gigabits per second per ladder to be read out, out of the blue, if you do not have any
STFC-RAL-CR03 R61: trigger level implemented. Of course, this is not impossible. If you have a look at, weight privilege and multiplexing links, you can have all the inter, let's say, nowadays,
STFC-RAL-CR03 R61: silicon photonics links with 25 gigabits per second each, so you can aggregate those in a single fiber, and you can end up with such amount of, let's say, of rate. We've also been, pushing this limit to
STFC-RAL-CR03 R61: twice as much. So we can possibly, in 2048, have such bandwidth available for reading off the detector without the need of a trigger.
STFC-RAL-CR03 R61: And these are extremely low-power IMP objects.
STFC-RAL-CR03 R61: These are the… of the evolution of… sorry about the fractional, let's say, number, but this is the first layer, this is due to the… this is layer 0, layer 1, layer 3.
STFC-RAL-CR03 R61: So this is a C++ feature. This is the first layer, the one closer to the beam. Number of kits per batch processing, it decreases, 2 centimeters, perhaps centimeters, so this is 1.
STFC-RAL-CR03 R61: 4cm, 2.5cm, 3 centimeters, and these are the barrel layers. So, eventually, it will drop quite dramatically.
STFC-RAL-CR03 R61: with LUCA, so the other simulation.
STFC-RAL-CR03 R61: We were estimating the amount of radiation level, so both the TID, so ionizing dose, and the flux, the fluence.
STFC-RAL-CR03 R61: For these two kind of process, IPC and related data, relative are the ones that are mostly affecting the probability action.
STFC-RAL-CR03 R61: And, you can see that the first layer is basically IPC.net.
STFC-RAL-CR03 R61: Most of the others. And eventually, once you move out, the disks, but still are dominated by the IPC contribution. Any other fluences. These kind of fluences are not posing any problems for the kind of maps that would be developing by the R&D, which is going on.
STFC-RAL-CR03 R61: What is different? This is what other stage of the feasibility records, so it was, March 30, 31st, when we published it.
STFC-RAL-CR03 R61: the… there were some improvements in the simulation. We also switched on Azure and operations in our
STFC-RAL-CR03 R61: simulation, as I will show you, these are very tiny effects, because,
STFC-RAL-CR03 R61: the effect is less than 10%, then we can get rid of them quite easily. We even lowered the thresholds, which were up the order of 300 electrons, down to zero.
STFC-RAL-CR03 R61: And this is the effect. It appears, like, this peak here, at very low energy, below 2K,
STFC-RAL-CR03 R61: And this is the bulk. This is 15 micron thick sensors, as the one that we have put in the simulation. The most probable peak doesn't, of course, shift, and only appears at the very low edge.
STFC-RAL-CR03 R61: Oh.
STFC-RAL-CR03 R61: If you zoom in, you can find that you can appreciate the 1.8 cap from the silicone K edge.
STFC-RAL-CR03 R61: And the fluorescence contribution is well below that.
STFC-RAL-CR03 R61: So these are the kind of, let's say, things that you can easily get rid of if you have, let's say, if you apply, let's say, a threshold here, let's say something electrons, while keeping the bulk of the signal, of the Landau shape, okay? So in our case, we have
STFC-RAL-CR03 R61: 14, 4,500 electrons, as the most probable, you can easily apply a cut at all of 600 electrons and still be very efficient. In the case of SLD, due to the different thicknesses of the sensors, we had,
STFC-RAL-CR03 R61: most popular signal, and they were having some kind of structures here. I don't know exactly what's the difference between the two, but you can appreciate it a very, I mean,
STFC-RAL-CR03 R61: edge of facials, and they have a very quite big peak, and then a growth starch up here, up to over 20 cap or so, which may eventually, it is my guess, be some synchronization element.
STFC-RAL-CR03 R61: Hits. But this is not my business to understand this kind of things.
STFC-RAL-CR03 R61: Just to show you that, if you take ARCADA, this is a test beam we recently did at Familab, we scan the thresholds, and we also, and, let's say, full, calibration using, some fluorescence measurements.
STFC-RAL-CR03 R61: We can now convert this black ABC cams into some electrons, and this is for 200 thick sensors. We can go down, quite easily down, order of 300 electrons, without losing any efficiency. The efficiency is 95% above that.
STFC-RAL-CR03 R61: So we are confident that we can run these kind of detectors quite efficiently.
STFC-RAL-CR03 R61: Yet another,
STFC-RAL-CR03 R61: problem that Chris mentioned was, are you sure that you're looking some backsplashes? Because it was presenting some evidence that we were not seeing these backsplashes. So the… he pictured one linear plot.
STFC-RAL-CR03 R61: In, one of these, time of arrival of hits with respect to the, batch crossing,
STFC-RAL-CR03 R61: time to zero, and it was showing that there was basically no bits, huh? Instead, if you zoom in, and you have a lot scale, likewise the one that you were showing for C cubed.
STFC-RAL-CR03 R61: we do see, backsplashes. So these are it's hitting the detector, which is coming, order of up to 30, 40 nanoseconds later, the crossing, which is an indication that backsplashes occurred, and we do see some
STFC-RAL-CR03 R61: of the tweets back into the vertex detector. And Y is not exactly the same as the secure one? Well.
STFC-RAL-CR03 R61: you can easily check it, because in the C2, this is a linear collider. I'm not completely sure that it's C-tube, but it takes linear collider, beam arrangement, you can approve that the vertex… sorry, this is the interaction point, and this is, how does the beam pipe, increases in order to
STFC-RAL-CR03 R61: People with a larger, very much larger.
STFC-RAL-CR03 R61: IPC, and this is the first bucky element, which is, the, You're messing with truck.
STFC-RAL-CR03 R61: Which is about 3 meters away. So if you make math, going there and back.
STFC-RAL-CR03 R61: It takes 29 seconds, and this is the reason for this week.
STFC-RAL-CR03 R61: Our measure… our, let's say, vertex luminosity calorimeter is only at 1 meter.
STFC-RAL-CR03 R61: And we expect order of, let's say, 8 nanoseconds. There is some enhancement here, but most presumably there are also other structures that we also see. So, these are bounce-back photons in our vector detector. So, we do see them.
STFC-RAL-CR03 R61: It's the fact that we are far less
STFC-RAL-CR03 R61: object in printing here with respect to those which are very, very… at the very low angle in the… in the luminos, in the CQ.
STFC-RAL-CR03 R61: Counter-argument. Can we use Fluka?
STFC-RAL-CR03 R61: To estimate the amount of deeds.
STFC-RAL-CR03 R61: But, yes.
STFC-RAL-CR03 R61: If you know that, using this, Basilisk combination.
STFC-RAL-CR03 R61: And so this is the equivalent dose, that you can get… the equivalent fluence, sorry, that you can get from electrons with 20, and basically, fluids induced by electrons at this energy. This is the energy of these electrons, and this is,
STFC-RAL-CR03 R61: More or less, let's say, a factor of 20 times smaller
STFC-RAL-CR03 R61: With respect to protons, okay, in this calibration. So if you assume that all the electron-positons that we do see inside our vertex detector are due to these electrons and positrons, so whatever fluence you compute in Flucap.
STFC-RAL-CR03 R61: You end up exactly with the same order of magnitude, using the same five factors, 3 and plus S75, that we do see in general.
STFC-RAL-CR03 R61: So, basically, having two kind of simulation tools, which are different, and making such a very strong assumption, currently, we do end up with the same order of magnitude of
STFC-RAL-CR03 R61: number of hits inside the project. So this, to me, looks quite robust, having a completely different, independent, simulation tool.
STFC-RAL-CR03 R61: Yet another difference between SLC and NFCC. This is kind of an arrangement for the vertex detector second case, vertex detector 2, in which instead is the last stage of vertex detector after 1996.
STFC-RAL-CR03 R61: So this was the most, let's say, efficient vertex detector ever done, with, full coverage and, very nice, asymptotal, coverage. This was… was the arrangement for the forward, let's say, region.
STFC-RAL-CR03 R61: In front of the vertex detector, and that this detector is a few centimeters away from this.
STFC-RAL-CR03 R61: point, there were this, Luminosity, timestamp silicon sandwich called, Mazik.
STFC-RAL-CR03 R61: Medium angle, silicon, colorimeter.
STFC-RAL-CR03 R61: which has been dismantled to make room for the masks here, once they install the Vertex Detector 3 in operation.
STFC-RAL-CR03 R61: These are the masks.
STFC-RAL-CR03 R61: Which are protecting from synthetic correlation.
STFC-RAL-CR03 R61: And they're called, N3. And easiest are the, luminosity calorimeter.
STFC-RAL-CR03 R61: Which, which is Ella and Sat, which did move.
STFC-RAL-CR03 R61: Is that… about one meter away.
STFC-RAL-CR03 R61: And, you can appreciate a lot of statues here, okay? This manzik, actually, was,
STFC-RAL-CR03 R61: having the same annual acceptance of the FCC LumiCal, Order of, 30…
STFC-RAL-CR03 R61: In the audience, the way I go.
STFC-RAL-CR03 R61: However.
STFC-RAL-CR03 R61: Instead of being 1 meters away, it was only 20 centimeters away from the vertex detector, so very, very close.
STFC-RAL-CR03 R61: And they thought, whatever, you splash.
STFC-RAL-CR03 R61: Here, when we're directly passing back into the vertex detector.
STFC-RAL-CR03 R61: Keep in mind that you have
STFC-RAL-CR03 R61: 50 centimeters… 5cm wide diameter wheel path.
STFC-RAL-CR03 R61: So, our culture is quite big with respect to 2 centimeters that we do have at the FCU.
STFC-RAL-CR03 R61: And what we did, using GenePic, exactly the same program, we estimated the number of particles which eventually would be scattered off these three structures, the mask.
STFC-RAL-CR03 R61: The mass… mass… sorry, MASIC, the mask shielding the, central radiation, and the luminosity detector.
STFC-RAL-CR03 R61: And we assume… if you assume that the number of particles are the photons or electrons which are hitting these structures is… sorry, which are hitting the vertex detectors proportional to the E plus and minus pairs that are hitting these structures.
STFC-RAL-CR03 R61: We can compare SLD with FCC.
STFC-RAL-CR03 R61: So… 7% Elon Musk.
STFC-RAL-CR03 R61: 22% is, is hitting the LMSAT, and, let's say, very few numbers, 5 to 10 less is the L.
STFC-RAL-CR03 R61: So, you end up with such number of particles bounce back per, say, batch crossing, possibly. I mean, this is the upper limit, of course.
STFC-RAL-CR03 R61: bunching on this section. If you do the same for FCCE, only a tiny fraction hits Lumica in the form part, because of the very far
STFC-RAL-CR03 R61: Let's see… It's 1 meter away, but still, the problem is that, the…
STFC-RAL-CR03 R61: the size of the green strangle is different, okay, with respect to SLD. So we end up with a fraction of a particle hitting the
STFC-RAL-CR03 R61: sorry, the lumica. So these are a number of particles that are hitting these structures, which eventually, attached on those will be backscattered inside the vertex integrator.
STFC-RAL-CR03 R61: So, sorry about this table, it's quite complicated, but the main message here is the following. So, if you work out the map, on the left, in red, is the SLC,
STFC-RAL-CR03 R61: And on the right, in blue, is FCC.
STFC-RAL-CR03 R61: So you can either compute the number of expected particles inside the vertex detector acceptance direct, you know, directly.
STFC-RAL-CR03 R61: So, these are the number of particles hitting per batch processing. Obviously, no.
STFC-RAL-CR03 R61: The number of particles hitting per second.
STFC-RAL-CR03 R61: Quite much more, over 500 millions, but if you scale down how much you integrate.
STFC-RAL-CR03 R61: In your vertex detector readout.
STFC-RAL-CR03 R61: Due to the fact that this is a thousand times higher, 200,000 times higher, with respect to the one that, integration time of FCC, you can easily reduce this number to about the same number. Order of 500 expected.
STFC-RAL-CR03 R61: electron positive compressed, directly integrating In the readout window of your data, where it's go back.
STFC-RAL-CR03 R61: What happens to the backflash? Oh, now we have to take it with a grain of salt, because these are not, let's say, the numbers that you expect, but this is the proportional to the number that you eventually
STFC-RAL-CR03 R61: would be bounced back into the vertex detector. It's just the ones that are hitting the bulkier structures on top, I mean, in the very forward reach.
STFC-RAL-CR03 R61: So, and you can notice that even if you remove, this only happens for the vertex director 2 in the SLD, but this was not there anymore for vertex director 3. Vertex director 3 only had this LM sub. It didn't move, and also M3 doesn't make anything.
STFC-RAL-CR03 R61: So here, the proportion between the direct and backsplashed is We're under, I guess, 1,000.
STFC-RAL-CR03 R61: Whereas, in the case of FCC, the direct respective bench splash is 500 against 20, so I would say that the relative proportion between the two is quite different.
STFC-RAL-CR03 R61: So we had much more.
STFC-RAL-CR03 R61: compared to FCC, backsplashed object in the SLD detector expected with respect to those that eventually would be backsplashed, been backsplashed on the lumica in FCC, because of the different geometries, because of the different crossing angle, because of water, and we discussed in so far.
STFC-RAL-CR03 R61: So, I would say that the reason to see much more
STFC-RAL-CR03 R61: activity in the vertex detector, actually, SSD, might be, it's not yet proven, yet to run it in your simulation, also because of these effects.
STFC-RAL-CR03 R61: Other background sources, of course, being gas interactions, we have estimated, and, being along with SkyTrain, you can see that this is…
STFC-RAL-CR03 R61: proportional, very subliving respect to IPC. If you remember, this is a fraction of a kilogram rate per year, whereas in the other case, we have 70, 100 kilogram per year.
STFC-RAL-CR03 R61: Signal radiation. This is a tricky object. Of course, everybody is aware that whatever you do, you will eventually have it inside your data. We are not stupid to understand to say that we will not have any. But, but…
STFC-RAL-CR03 R61: we've been doing simulations, using both VIN core, which eventually will be We're also using a,
STFC-RAL-CR03 R61: Optic simple attractions, meaning that groups are a little bit offset with respect to the central magnetic line.
STFC-RAL-CR03 R61: But we also have some bean tails, depending on the… what is called by the machine people, the lifetime of the bee. Either, you know, very, very small, let's say, tails, or very large tails, and this will reflect to one day lifetime, up, down to 5 minutes lifetime for the bee.
STFC-RAL-CR03 R61: So we've been doing this, this, this, this, simulation. The bulk of the central radiation is, of course, produced upstream in the interaction region, and will be stopped by the collimators.
STFC-RAL-CR03 R61: We have polymeters inside, 2.5, 2.1 meter inside the attraction region, and this will also be stopped.
STFC-RAL-CR03 R61: By this mass here, okay? Between QC1 and QC2. And eventually, here at, at QC1.
STFC-RAL-CR03 R61: So, we are playing with the shape of these masks.
STFC-RAL-CR03 R61: In these days, and there is a continuous feedback that we're starting right now to experiment, and the machine people that doesn't… do not want masks, because, the VMAP pressure will be smaller, the,
STFC-RAL-CR03 R61: impedance of the beam would be higher. So we have to fight against, between two communities.
STFC-RAL-CR03 R61: The back of the radiation goes very, very straight.
STFC-RAL-CR03 R61: In the way forward, it will be extracted, these final keywords that also Chris alluded to.
STFC-RAL-CR03 R61: is going very well, very, very, say, in the front, with these dumps, for which we have, some fancy things, such as liquid lead, absorbers, or things like that. And these are being fully circulated using FUCA, aside the beam.
STFC-RAL-CR03 R61: The dim light.
STFC-RAL-CR03 R61: Injection losses,
STFC-RAL-CR03 R61: You know that, once, every 10 seconds, we have to inject tiny fractions of the beam from the booster inside the FCCE collision ring.
STFC-RAL-CR03 R61: And,
STFC-RAL-CR03 R61: basically the septum that are diverging the beam, and then you get some fraction of the beam, pop up the beam, and then pre-sequence again. So what we did, this is the power calculated over 700 turns.
STFC-RAL-CR03 R61: In different locations. This is the injection.
STFC-RAL-CR03 R61: And there's the first IP, then there are collimeter sector, second IP, third, the fourth.
STFC-RAL-CR03 R61: So, it looks like that the inception… I mean, the losses are mostly focused, of course, on the clinician system, around VIPs.
STFC-RAL-CR03 R61: And there are some, let's say, ideas that are doing something.
STFC-RAL-CR03 R61: Of course, there are, let's say,
STFC-RAL-CR03 R61: Showers originating from these collimators inside the detectors. And these are the showers that, Hi, this is amazing.
STFC-RAL-CR03 R61: integrated picture. I will give you the numbers in a moment. So, we can appreciate that there are towers in pinging and beyond chambers.
STFC-RAL-CR03 R61: And there are background things here in the pool.
STFC-RAL-CR03 R61: where we cannot put any shielding from 30 meters away from the cabin. The cabin are a bigger order of 60 meters long.
STFC-RAL-CR03 R61: And these are the hits in Carmen, which are placed inside the detectors into the, into the vertex detector, and all the other detectors. In Carmena, inside the very central region.
STFC-RAL-CR03 R61: If you look at the numbers, this is the number of particles that you do expect in a 25 nanosecond window, average over all these 700 terms.
STFC-RAL-CR03 R61: So it's quite a tiny fraction of… because mostly distributed on the full surface.
STFC-RAL-CR03 R61: That's it. So, conclusions. I hope I…
STFC-RAL-CR03 R61: Show you that, while progressing with the, vertex detector layout and the machine detector interaction region, we've been doing this to minimize the effects of the material budget and,
STFC-RAL-CR03 R61: limiting the effect of the backgrounds. The background estimates are all carried out using JR with realistic machine conditions, including non-gash and ejection background, which I was shown here before.
STFC-RAL-CR03 R61: IPC, so far, is the one which has been mostly giving us the largest effect. Studies of synchronization will be soon coming.
STFC-RAL-CR03 R61: And of course, it would be nice to see, even for us, where to put and where we end up as a compromise with the machine people, in terms of shielding.
STFC-RAL-CR03 R61: Comparing FCCEPN to SLD, we were able to reproduce the main features of their backends, so I think we are confident understanding the reasons why they're different.
STFC-RAL-CR03 R61: And, one thing, if you want to join FCC, one more reason. The beam structure and the crossing angle helps a lot to control the backgrounds, to have less backgrounds. Sensor technologies will allow to have much less information time.
STFC-RAL-CR03 R61: More charge, lower thresholds.
STFC-RAL-CR03 R61: So another magnetic field of two Tesla, FCC eventually can do higher energies, to keep the IPC, backgrounds confined. Luminosity calorimeters, also affect quite a lot.
STFC-RAL-CR03 R61: The backgrounds. We have much more clean and well-designed luminosity panorameter. Quite away, but still inside the detector.
STFC-RAL-CR03 R61: And, relative to SLC, to S2SLD, we actually see, backslashes are minimal respect, multiple patterns.
STFC-RAL-CR03 R61: If I make interesting call.
STFC-RAL-CR03 R61: We have time for questions.
STFC-RAL-CR03 R61: Or maybe we should just give to Jens and Bill to carry the discussion. Yo! I mean, other people can ask questions. I was gonna try and channel my in-dress, which is really hard, because neither am I that enthusiastic for that.
STFC-RAL-CR03 R61: Other people? Yeah.
STFC-RAL-CR03 R61: Well, I could start with one. I mean, maybe… I don't really follow what it was about the crossing angle that made such a big difference. Could you maybe just explain that?
STFC-RAL-CR03 R61: So the crossing angle makes the difference, because the bulk of the…
STFC-RAL-CR03 R61: The bulk of the, of the… of the things is this young… Oh, sorry.
STFC-RAL-CR03 R61: Unfortunately, scale.
STFC-RAL-CR03 R61: But the bulk of the IPC is being produced in the very forward.
STFC-RAL-CR03 R61: Here's the crossing angle.
STFC-RAL-CR03 R61: And, it's following.
STFC-RAL-CR03 R61: exit of the beams. Whereas in the SNC, we have head-on collisions.
STFC-RAL-CR03 R61: And that… yeah.
STFC-RAL-CR03 R61: on the same axis, on the… I mean, the beam and the vertex detector share the same axis. And therefore, in one case, you exit.
STFC-RAL-CR03 R61: vertex and text, huh?
STFC-RAL-CR03 R61: The other physically dropped.
STFC-RAL-CR03 R61: In both cases, you've got the beam axit in the verdict. The photons go forward, and they hit the zero degree kilometer in whatever it was, in SLC, whereas in FCCEE, they will follow the beam axis, and they will hit something further down the line.
STFC-RAL-CR03 R61: This is a structure that is 400… this is 400 kilogt. It's a structured in a very far hand, and it's being dump.
STFC-RAL-CR03 R61: Something that we do not tend at SNC.
STFC-RAL-CR03 R61: I'll click.
STFC-RAL-CR03 R61: I'm really putting another… it was a very nice presentation last meeting, and one reason to join us, in which there was another simulation code called WPACs.
STFC-RAL-CR03 R61: which is being used for building a collector, a Slack, and we're showing an animation
STFC-RAL-CR03 R61: of the B, and this hypersen,
STFC-RAL-CR03 R61: interactions as they move along with the V.
STFC-RAL-CR03 R61: And you can easily appreciate why I need to look at that, what's happening.
STFC-RAL-CR03 R61: So the beam separation in the SLD was… was a… was a high-field magnet, presumably, after the, after, after the beam. Okay, I see, I see. All right, good.
STFC-RAL-CR03 R61: More questions in the room.
STFC-RAL-CR03 R61: Could you say something about the degree to which the services or the,
STFC-RAL-CR03 R61: for the vertex detector have been, kind of, designed. I mean, I spotted in one of your earlier slides on the material. There was a little bit of aluminium in there, which I assume… This, this, this,
STFC-RAL-CR03 R61: This layout is more or less, I mean, as for essence.
STFC-RAL-CR03 R61: The inner vertex detector, and most of the services
STFC-RAL-CR03 R61: From the outer work at the detector, and the disks were there.
STFC-RAL-CR03 R61: So we have air cooling for the inner vertex detector, and water cooling for the outer vertex. We have also simulated the material
STFC-RAL-CR03 R61: Of the cables.
STFC-RAL-CR03 R61: maybe some of the electronics are not there, but you can appreciate the level of the… of, let's say, things in this time structure here, for instance.
STFC-RAL-CR03 R61: And the very… I mean, these are… I mean…
STFC-RAL-CR03 R61: There are, of course, all the cables. This is a flat, long barrel structure, and this is inside the deck. You can appreciate the, I mean, the bulk.
STFC-RAL-CR03 R61: Object here is the carbon fiber.
STFC-RAL-CR03 R61: Of course, there is, aluminum, cadets. Aluminum flex cables? Flex cables. These are the ones, likewise, the M3B…
STFC-RAL-CR03 R61: And, but at the edge, of this region.
STFC-RAL-CR03 R61: Suck.
STFC-RAL-CR03 R61: You cannot probably appreciate that much, but at the… I mean, there are supports here at the very edge.
STFC-RAL-CR03 R61: All the battle sections, here and there.
STFC-RAL-CR03 R61: Which are made of peak material.
STFC-RAL-CR03 R61: And these are reflected out of these peaks.
STFC-RAL-CR03 R61: Okay, so that's kind of your service. Exactly. And for the inner vertex, it's all run out along the axis? Well, actually, now… How does that mix with the beam pipe?
STFC-RAL-CR03 R61: Okay, this is yet to be, established. Either we run it all along the beam axis, or we exit with this, with this, I mean, in this widget here, sorry, this widget here.
STFC-RAL-CR03 R61: in this region here. Now, the most… I mean, we are building a setup understand the routings.
STFC-RAL-CR03 R61: other cables.
STFC-RAL-CR03 R61: And it would be a one-to-one
STFC-RAL-CR03 R61: set up, in order to understand whether we can afford, making the curvature of the green part… of the
STFC-RAL-CR03 R61: Adaption of the air cooling.
STFC-RAL-CR03 R61: Together with the, the tables for the results.
STFC-RAL-CR03 R61: We think that we could have, let's say, some electronics here, let's say a patch panel, which then brings out using the fabrics.
STFC-RAL-CR03 R61: It'll be much, much less…
STFC-RAL-CR03 R61: Okay, so it said on the end of the barrel, effectively, is where you're… Yes, there will be some… some effect there, which is yet to be understood. I mean, we didn't put… this is the most engineered version of the…
STFC-RAL-CR03 R61: You said WDM links, very low power, what do you mean by that? Because you had 12 watts in your whole inner layer.
STFC-RAL-CR03 R61: But I'm assuming per leather, you must be talking about a water view. These are only the silicon, assuming that we dissipate that it can be used per square centimeter.
STFC-RAL-CR03 R61: Now, you know very well that, likewise in Alice, ITS3, there would be regions in which we have 20 milliwatts per centimeters, and the other 700 milliwatts per square centimeter. And, at the moment,
STFC-RAL-CR03 R61: the, let's say, modulation of the chip.
STFC-RAL-CR03 R61: Beyond least, let's say, existing relationship, which is now on the market, is the one from LHCB.
STFC-RAL-CR03 R61: Great, too.
STFC-RAL-CR03 R61: I don't have figures from that, but
STFC-RAL-CR03 R61: you can think of having more or less the same power as the low-power GPT.
STFC-RAL-CR03 R61: So, only 700.
STFC-RAL-CR03 R61: A milliwatt per square centimeter or so.
STFC-RAL-CR03 R61: there will be some localized object where you can have such a bulky object. So, so I guess with one, I mean, what you call a stain here is what you call a ladder elsewhere. Yes. So, so, so on layer one, as Jen said, that probably means that…
STFC-RAL-CR03 R61: If it's something similar to LPGBT, you're…
STFC-RAL-CR03 R61: power from your optical conversion is comparable to the 12 watts of power you get across the whole… This is the state of the art today. We have to think about in that, maybe 20 years from now, what can be affordable using 7 nanometer fronts, maybe much more… much lower.
STFC-RAL-CR03 R61: Does it mean? Yep.
STFC-RAL-CR03 R61: I'm trying to channel my inner crystal.
STFC-RAL-CR03 R61: So, thanks for highlighting the X-ray fluorescence and the Auger electrons. I think everybody switches that off, because as far as I can tell, it is painfully slow and horrible to see. Exactly, because somebody is how you can do it. You showed a slide with, energy deposited, I think, per layer, but I'm not quite sure.
STFC-RAL-CR03 R61: No, this is the number of hits. So it's K… number of hits with energy, energy loss per layer. This one? No, no, it was, because you showed us a small spike that appeared for the fluorescence, I think.
STFC-RAL-CR03 R61: Yes. No, but he did not put it, yeah. So…
STFC-RAL-CR03 R61: In the end, it doesn't matter. You show us the, vertex barrel hit energy deposit, I'm assuming that it's within one layer.
STFC-RAL-CR03 R61: Because you're also pointing out… I don't remember whether it is the first layer, or… You pointed out the 4,500 electrons on it. Yeah. So that was the assumption that you're passing through something like 50 microns of silicon. Yes. Now…
STFC-RAL-CR03 R61: you're… you've got 25 by 25 microns pixels. Most of them will be at an angle. I'm assuming you have to go much lower in terms of the charge per pixel that you collect? Well, I think that that…
STFC-RAL-CR03 R61: I haven't metaphora.
STFC-RAL-CR03 R61: Yeah, there is zero.
STFC-RAL-CR03 R61: This is the… on the same test bin.
STFC-RAL-CR03 R61: And the temperature protons per formula.
STFC-RAL-CR03 R61: This is the four and a half… micro residual.
STFC-RAL-CR03 R61: As measured by this test beam. If you compare with the 7 point respected by the binary resolution, there are a factor of 2 better.
STFC-RAL-CR03 R61: Is this with analog clustering? This is, with, this is with analog clusters using, the Arcadia.
STFC-RAL-CR03 R61: it presumably means you have to go much lower in threshold than at least half your charge that you expect. I mean, this is not the end of the story. Yeah, so… Yes.
STFC-RAL-CR03 R61: The worry clearly is that the thinner the sensors go, the more you're going to have impact from very low-energy X-rays depositing. Exactly. And because the low-energy X-rays sit isolated and will only hit one pixel, you can't really reject it based on a threshold or something.
STFC-RAL-CR03 R61: Unless you know that you're always going to be above first. Now, we are ugly people, we work on hand-oplight stuff, so everything's stinkin'.
STFC-RAL-CR03 R61: Awesome. Ish.
STFC-RAL-CR03 R61: But it means so…
STFC-RAL-CR03 R61: at the moment, we don't see any of these issues, largely because we're just so high in threshold. Exactly, exactly. Whereas the lower you want to go, and the lower you want to go in resolution, the more this is going to eat away at you. Yeah, but here, for instance, these are… these are IKS3.
STFC-RAL-CR03 R61: Yes. You can go down to 100, 150 thresholds. Yes. And you can afford having a resolution which is the one that you expect to.
STFC-RAL-CR03 R61: Agreed. And then, at that point, will you keep running? How much do you know that you've run so much fluorescent simulation that you know that you're not going to be swamped by low-energy X-rays from
STFC-RAL-CR03 R61: tertiary. I personally agree with the feeling that we shouldn't go down to 10 mic… 10 micron introduction. Agreed, agreed. Maybe others, Zionists, do think they can get, let's say…
STFC-RAL-CR03 R61: That kind of things work. This is why I'm sponsoring Arcadia, 40 micron sensors, at the expenses of the
STFC-RAL-CR03 R61: of the, that I was showing you before, at the resolution, because in the end… sorry.
STFC-RAL-CR03 R61: At the end, the resolution is dominated at the moment by the green pipe. Of course, we are also working to minimizing the material budget for the pipe.
STFC-RAL-CR03 R61: We've got it.
STFC-RAL-CR03 R61: But you're not going to gain much from going 25 micron to accelerated. Exactly. Yeah, exactly. So my, my prejudice is that,
STFC-RAL-CR03 R61: It's true that you want to go down.
STFC-RAL-CR03 R61: But you do not see… See, dramatic differences between the
STFC-RAL-CR03 R61: Ultralight version, which is this kind of Let's say, and your traditional… approach. I mean…
STFC-RAL-CR03 R61: Really, there might be other… this is statistics. There might be other systematics.
STFC-RAL-CR03 R61: On top of that, that really probably makes the difference when you… I mean, in the end, this is just one figure, the impact parameter. In the end, what has been shown, for instance, in one of the
STFC-RAL-CR03 R61: We're creating.
STFC-RAL-CR03 R61: The impact, mostly, on this decay mode is coming from the beam pipe. We have to lower the material bunch of the beam pipe down to the level that a factor of 2 is smaller with respect to the one that we have now, in order to appreciate any difference coming from the vertical type of resolution.
STFC-RAL-CR03 R61: My other feeling would be that,
STFC-RAL-CR03 R61: be fully safe. We should be starting, I mean, colliding beams, adding a vertex detector that is, let's say, basically tuned to do the kind of physics that we would expect to make it in the very first time.
STFC-RAL-CR03 R61: try to estimate the balance at that stage, and then eventually come back with a much more aggressive design.
STFC-RAL-CR03 R61: To be, let's say, safe enough.
STFC-RAL-CR03 R61: To make sure that they understand where's the bag goes, and then…
STFC-RAL-CR03 R61: design a metal vertex detect. I mean, otherwise.
STFC-RAL-CR03 R61: This was also the attitude, you know, too, but eventually they ran up.
STFC-RAL-CR03 R61: You do that for the full… the full vertex detector, or just the inner layers? Insertable inner layer. I think the most crucial one is the vertex… the innermost layer, I mean, say, layer 0.
STFC-RAL-CR03 R61: In fact, in this respect, we also think of having a somewhat other crazy idea that came in mind.
STFC-RAL-CR03 R61: Is to put these, ladders right on top of the discipline part.
STFC-RAL-CR03 R61: Yes. And try to overcome… first of all, yeah, you minimize the effect on the second and third layer by removing all the material.
STFC-RAL-CR03 R61: Steve Material.
STFC-RAL-CR03 R61: Sport material. And then you… and profit of the cooling on the pipe, Cool down the detector.
STFC-RAL-CR03 R61: In that way, if you compare.
STFC-RAL-CR03 R61: I mean, you can go, really, 2 millimeters, in the board.
STFC-RAL-CR03 R61: Inward, with respect to the current design, and you can gain quite a… quite a lot, because in the end, instead of having the ultralight, so the curved layout, is giving you worse resolution.
STFC-RAL-CR03 R61: than going… Gaining respect to what you can gain by
STFC-RAL-CR03 R61: Putting it, closer by 2 millimeters.
STFC-RAL-CR03 R61: So, this can really make a lot of impacts.
STFC-RAL-CR03 R61: So you can think of having such a design. Of course, Vibrations.
STFC-RAL-CR03 R61: To be kept, smaller than,
STFC-RAL-CR03 R61: 2 microns, because if you aim to have a 3 micron resolution, it can always be worn by vibrations.
STFC-RAL-CR03 R61: But this is yet another story.
STFC-RAL-CR03 R61: in kind of designing a vertex detector, there are very tiny effects, such as these fluorescence, and these vibrations, and… I mean, you're really hitting the point where you… your technology allows you to do something.
STFC-RAL-CR03 R61: Yes, last question from me. Fluorescence again. The… I asked you this via email, and I think you gave me a half a response, and then said I should come to PMDR meetings, which I should.
STFC-RAL-CR03 R61: But the, have you run activation studies of material? Because the…
STFC-RAL-CR03 R61: Lesson learned that we have is the material ends up being more than you had originally planned for, always does.
STFC-RAL-CR03 R61: And…
STFC-RAL-CR03 R61: Ideas like being able to swap in a layers definitely don't work, as far as we can tell. Not easily.
STFC-RAL-CR03 R61: But what you end up with is more material than you planned for, so then the question is, how much might you be dominated by
STFC-RAL-CR03 R61: random-induced activation. Okay, so, yeah. Given the number of particles we saw earlier… No, the number of particles is much, much lower with fluencies that I was showing you are much way less respect to what we had with CMS or apples. So, no doubt.
STFC-RAL-CR03 R61: Then, there is another point, iteration type, that's… So, 1 microsecond.
STFC-RAL-CR03 R61: Or less, actually, you know, that are these three wishes to go to…
STFC-RAL-CR03 R61: possibly 500 nanoseconds integration time, in some cases. This we like, of course.
STFC-RAL-CR03 R61: are not correlated. Thirdly.
STFC-RAL-CR03 R61: there is a FUCA team, which, in contrast exactly this point that you raised, I mean, how much deactivation
STFC-RAL-CR03 R61: Yeah, yeah. Inside of the sector. So, there will be some studies eventually, within the next couple of years. I mean, we know that we are now in the middle of making the pre-TDR phase of FCC. So, during this time, there will be studies done for addressing also this issue.
STFC-RAL-CR03 R61: And finally, I think it's important to understand that,
STFC-RAL-CR03 R61: from the point of view, I mean.
STFC-RAL-CR03 R61: everybody, I hope, understands that, I think we can see.
STFC-RAL-CR03 R61: That has tremendously higher problems in part of the commission for the constructing attacks.
STFC-RAL-CR03 R61: These are clean events.
STFC-RAL-CR03 R61: Even if they're spoiling, spoiled by, kids here and there.
STFC-RAL-CR03 R61: Currently, our simulation tool is able to overlay the two candidates at the level of digital search. So, we can even digitize the two things overlaid exactly the same cell, and see the effects.
STFC-RAL-CR03 R61: I personally don't think this will be any issue whatsoever for the impact on the tracts and the impact on the physics.
STFC-RAL-CR03 R61: need to be said that if you are interested in very, let's say,
STFC-RAL-CR03 R61: low, extremely low climbs ratios processes, like the one that I was showing you before, B2, K star delta, I doubt that this will have any effect on this kind of disease.
STFC-RAL-CR03 R61: On the other hand, due to the very large statistics, there are channels in which we have zillions of the air, decaying two two muons.
STFC-RAL-CR03 R61: when the time acceptance definition is needed, and therefore other effects would be probably dominated, such as, the mechanical stability, or how do you estimate the final alignment. So, overlaying it to the… to the very clean
STFC-RAL-CR03 R61: Remote pilot.
STFC-RAL-CR03 R61: Yep.
STFC-RAL-CR03 R61: So these are kind of…
STFC-RAL-CR03 R61: spots here and there, even SND was able to reconstruct these events very clearly. I would not expect this to be having a very big impact. Nevertheless.
STFC-RAL-CR03 R61: The more the people, the more status.
STFC-RAL-CR03 R61: I think and I hope.
STFC-RAL-CR03 R61: As a community, we can learn much more, having, new ideas, and,
STFC-RAL-CR03 R61: experience from the past, and whoever. I think that this is a great challenge for us to make sure that whatever we design, we will be able to
STFC-RAL-CR03 R61: You throw our nippies.
STFC-RAL-CR03 R61: They would shape. Challenging as it may be, I hope you can see from this, or take from this, that
STFC-RAL-CR03 R61: Chris was concerned about something, which came from his past experience, and has certainly managed to trigger a lot of people to spring into action, even in this department.
STFC-RAL-CR03 R61: Which, we're busy with other stuff at the moment, and yet… No, I really appreciate the inputs that you gave. Nevertheless, I want to be realistic and make things in a proper perspective.
STFC-RAL-CR03 R61: And, especially dealing with something that, he might not be knowing exactly, make less examples.
STFC-RAL-CR03 R61: Savings.
STFC-RAL-CR03 R61: We are actually over time, but… You're welcome, I'm still… Average year is here on 4.30, right? I'm still 4 o'clock, yes. 4, 4 o'clock, and you are welcome to join for lunch. You're welcome, yeah. So let's send Tabrizio again.