I don't know. Can you see the slides? Yes, yeah. Okay, so yeah, I'll be discussing
the plans for le CB during the upgrade. So, in the long shutdown, pass the long
shutdown for period and what we want to do with timing there. I'll just begin by
saying a little bit about the upgrade to have lacp. So it's going to happen in
about 2030, a little bit later than the CMS and Atlas upgrades. And we are going
to have an increase in the luminosity with respect to the upgrade one situation of
about 7.5. And in the run five and six, during this time, we expect to collect
something between 300 and 350. In bursts of data, it's going to be a very
challenging environment. As many of you already know. We're going to have an
increased amount of pile up and a few thousand charged particles that are
actually going to be entering the detector acceptance per bunch of crossing. This is
going to give us you know, many troubles. In terms of tracking, we'll have a lot
more ghosts and mismatch of primary vertices. And then of course, we can't
forget about that we're going to have a very harsh radiation environment, which is
going to be driving a lot with technologies that we actually need for
timing. And so now this brings me that, you know, in order to deal with the, the
extreme pile up and this problem with the tracking, we need many subsystems that
have dedicated fast timing in them. And so I've outlined here, which ones that I'm
going to be discussing. So we have the Veilleux, the rich detectors, the torch
and the electromagnetic calorimeter. ico. Now, a little bit about why we need timing
for detector performance. It will help for suppressing combinatorics and also
enabling time dependence CP violations also with reconstructing primary vertices
and associating with the right to events, this will be extremely important on the
right hand side you can actually see if the overlap of many primary vertices. So,
on the x axis you can see the impact parameter and on the Y Y axis, you can
actually see how the timing can actually disentangle many overlapping vertices and
so, this can be quite important. And on the bottom set of plots you can actually
see a good example of why this will be important for tracking as well. So, on the
bottom you can actually see the ghost rate efficiency and impact parameter resolution
for the baler detector with the current upgrade one geometry and you can see in
the black what we expect for up to One and then the read what we would expect an
upgrade to without any changes from the upgrade one geometry. And so you can
actually see quite significant deterioration of our detector once we go
to upgrade to if we don't actually do anything. And so timing is going to be
really important to keep the performance up to what we currently have. So now this
brings me to the different detectors I start with the bailer detector, which is a
silicon pixel detector. We find that already that just for the mismatch of
primary vertices, we're going to need something like 200 picoseconds timing
resolution for this detector just to keep the current mismatch rate at the current
current performance of about 1%. He's also going to be extremely important for
tracking you know the hits are going to be separated in this luminous region by
around 170 picoseconds RMS which means that We're going to need just timing
resolutions with about 10s of Pico seconds to distinguish these especially
overlapping hits. We also need to get past timing to really maintain adequate
efficiency during this time. So on the bottom right plot, you can see just a
simple simulation. It's not with the full LCD simulation. But nonetheless, it's very
insightful to see how different amounts of timing can actually improve your
efficiency during this time.
And again, like I said, radiation is going to be very important for all these things.
And so this is going to be something that's going to be actually fighting our
spatial and timing resolution, in a sense, and we're going to have to consider this
when discussing different technology choices for the approver below. And I just
want to say on the last point, that right now I show different scenarios, no timing,
hundred Pico seconds. 50 Pico seconds, you can even go a little bit better when it
seems from the latest simulations, you about 50 Pico seconds per hit or about 20
people seconds to track will seem optimal. For the below that we have. We want to
have an integrated sensor with a basic and basic sensors in one. The basic will be
based on the baler picks time picks family. And for the actual sensors
themselves, you know, we have many options that we're considering there's not one
single option that we've chosen. Some of the leading candidate candidates include
planar sensors, complainer's, l guides, 3d, or we can even consider things like a
monolithic design such as sea monster. Other factors as well. Like I said,
there's not going to be one single technology, maybe that's going to be used
throughout the whole sensor because at the moment, you know, there is no technology
that that's actually going to get us to the requirements that we need in terms of
the small pixel size that we require fast timing and also the radiation heart. Which
is going to be upwards of one times 10 to the 17th and EQ in the innermost layer.
So, we might consider using different technologies, depending on the radius away
from being pipe. But this is not set in stone yet. And you know, we have a little
bit of time to think about this. But we want to really keep all our options. Now
for the rich detectors, the rich one rich two detectors, these are drink off
detectors. And the timing is going to be really important there in order,
especially to keep the occupancy levels as current rate for the upgrade one, and you
can kind of see in the upper left plot, you have two overlapping ratings.
spatially, you can actually disentangle the two by just using timing. And it can
also improve in pattern recognition and reduction in background photons. And it
seems that also with In terms of primary vertices, you can separate them just with
about one nanosecond per photon, which gives us about a bit more than 100 Pico
seconds per track resolution. And finally, this one nanosecond is going to be enough
to reject the other time photons, which will require something like a three
nanosecond gate, just to remove some of the background. So in the bottom left
plot, you can see for the rich one, and the rich two different time stamps, and
you can see the signal peaks there. And so this is three nanoseconds is just for
simulation that doesn't include things like time walk or anything. And this
background is going to be about a few percent of which one and about 10% which.
Now moving on to the torch detector, this is also a drink off detector. It's
primarily a time of flight detector for particle ID. It's going to comprise a
sensitive microchannel plate with a multiplier tubes. It's aiming for Timing
resolution of about 70 Pico seconds per photon, which gives us around 15 Pico
seconds per track. And the time is going to really be important here because it's
possibly going to be able to help us suppress ghosts stemming from mismatch
between further upstream detectors of the veloz ut you can kind of see a schematic
on the bottom right? This year, or also there's some some decays that will happen
outside of the beyla detector, which won't have timestamps, and so this will actually
be very important for times. And like I said, it's mainly a time of flight
detector. And so the timing will also really help for identifying these really
low momentum particles
lower than about 10 gb.
Recently, a large scale a torch demonstrator has been built and tested at
the at CERN at the peanut beamline insane using a gv mix to beam mostly protons and
pions. You can see on the right hand side though, what the demonstrator looks like.
And the tests have indicated already that we are actually hitting the resolution
that we want of about 70 picoseconds per photon, which is what we would expect. So
these results actually are quite promising and it looks like that we're right on
track for this. And now finally, I come to the electromagnetic coil rameters are
equal. And it's gonna be quite challenging to simultaneously just, you know, optimize
energy resolution, the radiation hardness especially in the central layer. So on the
bottom, left plot, you can actually see the radiation dose expected for different
distances away from the beam pipe along that axis and you can see even we have
something Over 200 mega reds in the innermost parts. And so we're gonna have
to deal with this radiation as well. And, and we'll need fast timing also to
suppress component torques when forming by zero candidates and behind pads on the
case. And it also allows us like our other detectors to reject combinatorics. And and
you can actually really see how this is really deteriorating with the number of
primary vertices. So like, right now you can see on the bottom right plot, going
from one to four primary vertices per event, how much our signal degrades from
this and you know, if you think we're gonna have pileup of more than 40 and
upgrade to then this is really going to kill us. And so timing is really going to
be necessary to to improve on this. And here you can actually see See how the
timing would be affecting the efficiency and, and how we can actually improve on
this. So I show you kind of on the left plot, what you would get with no timing,
something with 50 Pico seconds that actually looks like we're going to need
something even tighter just a few 10s of Pico seconds already and this is going to
be provided by silicon detectors. These will either be embedded within the
perimeter material or as a plane outside of the the material itself. And really,
this timing resolution is going to be crucial to be you know, to really to
really keep the efficiency where we need it to be. Okay, so this brings me to a
summary. You know, upgrade to is going to be really challenging for late CB It's
gonna be, you know, effective 10 times in or close to 10 times increase luminosity
compared to the upgrade one, we're going to have increased pileup ghost rate,
problems with primary vertices, mismatching and reconstruction. And then
the radiation dose in some parts of the detector are going to be quite extreme as
well. And it's clear from the physics point of view that pass timing is going to
be necessary and many subsystems are going to carry fast timing. They load the rich
detectors, the torch and the EPL. And on the bottom, you can just kind of see a
schedule, which of course is going to be a little bit changed day because of the
current situation. But you know, we're still shooting around 2030 for this
upgrade. Okay, thank you. I hope I was in time.
Okay, thank you very much.
Any questions for Christopher?
I see two hands. So Stephanie was first
Go ahead. Okay. Thank you. Can you hear me? Yes. Okay, this is different by the
ankle. Yes. Just a question about slide number seven, was wondering whether you
since you concentrated on the on the V on one side, and on the other side, you were
thinking about getting some term resolution, also on the upstream tracker.
And on the dumpster in tracker two, I think you called it the mighty tracker,
because something of the order of 100 picoseconds seems to be rather achievable
in the few years from now.
So there have been some discussions on this, but I mean, nothing is really been
set in stone and it's
at the moment, I would say, No, it's not in the official plans for these. Thank
you,
Philip.
Please Go ahead.
You just need to unmute yourself.
Click No.
I didn't hear anything.
Okay.
Anything from sleep and
Okay, that is unmuted. There. It's muted again.
Okay, maybe we move on, though. Yes, we can hear you. Okay. So
on slide number eight. I'm wondering about the US in a symmetrical time time plots.
Where does this come from and what are the consequences? I couldn't
tell you where they symmetry. You're talking about the tail here on this
Gaussian district. Yes, yes. Oh, yeah. I apologize. I couldn't tell you about the
tail.
But the but the central Gaussian part it's about Sunday.