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Tell us about it's very taxing and very
taxing performance in round two.

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And so please go ahead matcha

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Good afternoon to everybody. It's a big
honor for me to be here and give this

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presentation on behalf of Dallas
collaboration about the texting detectors

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and the texting performance in Ubuntu with
Ellis. During the presentation, I will

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talk about the Alice experiment and in
particular, I will talk about the early D

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IDs detector in one year from today, I
will describe the event reconstruction and

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the taxing technique for the
reconstruction in particular of every

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flavor vertices. Then I will talk about
some interesting physics results. The

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TELUS was able to provide thanks to its
vertex in capabilities. And finally, I

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will spend few words about the IDS
upgrade. Elisa is general first experiment

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composed of a central model with up to
durability coverage between minus 0.9 0.9

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and immune spectrometers for up to 80. I
don't have the time to describe all the 19

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subsystems of Alice, I will just spot the
free of the detectors in the central

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bottle involved in the dirt fixing and in
the tracking. The inner muscle detector of

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the central model is the inner tracking
system, which apart from the localization

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of the primary vertex as his primary goal,
the localization of secondary vertices

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have a flavor as well in the case. And in
addition, the inner tracking system is

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involved in tracking helping the time
projection chamber on this duty. The temp

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projection chamber is the main tracker of
their Lisa and also identifies charged

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particles via the measurement of
ionization or unionization energy loss.

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Furthermore, an additional detector
involved in this trucking duties is that

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your team which also helps in the electron
identification we have the measurement of

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transitional radiation. As I said the
innermost detector of the central barrel

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is the inner tracking system, which is a
fully silicon detector composed of six

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cylindrical layers, the silicon pixel
silicon raised and silicon strip detector.

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This is a negreanu Laurie apparatus able
to cope with thousands of trucks per unit

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of rapidity that we have in high volume
collisions, and it's also able to detect

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simultaneously more than 10,000 trucks. As
I anticipated the main duty of these

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detectors is the reconstruction of
secondary vertices of every flavor abs in

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the Kazem in a separated way from the
primary vertex. In addition, this detector

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helps improve with the tracking and also
tracks as low particles that are not able

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to reach the TPC and be tracked their
events recorded by Lisa, reconstructed

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according to a predefined reconstruction
flow which starts with appealing Not a

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reconstruction of the interaction point by
exploiting the DSP. In the meanwhile, the

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tracking in the DPC starts starting from
the outer edges of the detector. And as

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soon as the tracks are reconstructing the
EPC, they are belong to the IDs. And this

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prolongation is done with a matching
efficiency quite high of order of 85 90%

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almost flat in terms of momentum and while
we produce those in our Monte Carlo

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simulations, as soon as the tracking
arrives, it it is also there's no

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particles can be tracked them by the usage
of the IDS stand alone, and then the

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prolong tracks are refitted outwards in
order to match the more efficient external

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detectors. And finally, the trucks the
global trucks are subject to a final

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inward defeat them that is very useful for
the improvement of the trucking

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performance as you can appreciate from the
left block, as soon as we require the

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prolongation of the tracks to the ITA from
TPC to IPS. we improve by a factor of two

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or three, the resolution in the curvature
of the track and as soon as this set of

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global tracks is ready, we can do the
final introduction vertex finding and then

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characterize completely the event. At this
point we can look for physics and in

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particular, reconstruct secondary vertices
of bofur. Weekly case, for example, their

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partner item and the case associated to
every flavor such as the measurements

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along to see, candidates associated to
these secondary vertices are then counted

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through these environments distributions
which are available after the

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reconstruction of secondary vertices. This
reconstruction is done by fully

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reconstructing the final Atlantic state.
And the vector x position is found by

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minimizing the distance among the Delta
trucks. The reconstruction of secondary

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vertices takes place by approximating
tracks close to primary vertex a straight

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line. But despite his geometrical

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approximation. Even in the worst scenario,
however, we have really negligible bias in

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the position of the vertex and this
simplifies all the procedure. The

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reconstruction of secondary vertices is
also very important in order to be able to

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exploit that at analysis level. Some
interesting variables such as decay length

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and pointing angle which are strictly
related to the topology of the decay. The

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secondary vertices reconstruction is also
performed the MonteCarlo simulations after

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correcting the reconstructed tracks in a
data driven way, for the For what concerns

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the input parameter is a parameter to
Primary Ethics. And with this procedure,

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we report to the resolution of the primary
value of the input parameter sorry, of

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trucks in MonteCarlo to match the one in
data. This procedure is very important to

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not only for efficiency corrections, but
also to provide unbiased templates for

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input parameter based analysis. After this
short introduction, I wanted to speak

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about some interesting physics results
from Alice in proton proton and lead light

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collisions. And to start with this, I show
you a typical lead collision. The teleSUR

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g study in 2018 taking campaign as you can
appreciate from these block them, the

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truck density in the central model in lead
collision is very high. We are talking

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about several thousands of trucks in
central events. And as you can understand

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that this makes the analysis in every
flavor of every flavor more challenging in

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his environment, due to the huge
combinatorial background that we have to

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cope with. But in any case, there are
construction of every flavor of secondary

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vertices is fundamental for Alice for the
study of the courtroom plasma that is

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produced experimentally via the API and
collisions. As a matter of fact, the

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chairman beauty quarks are produced before
they could use information. And for this

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reason, they can be considered effectively
unique probes of PGP since they experience

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the full evolution of the medium thanks to
the protection capabilities of Alice today

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I'm able to show you this very nice plot.
This compilation plot of the Chung flavor

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family, where you can appreciate the
nuclear modification factor array for

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different channels of drums. This variable
they are a is very important in heavy ion

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collisions, because it provides a natural
comparison between the behavior that we

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observe in the ion collisions and they
wanted to serve in in proton proton

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collisions. And this variable is
observable is sensitive to several effects

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such as the medium button energy loss, the
urbanization mechanisms that involve every

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quirks and effects related to
thermalization and especially fusion

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coefficients through PT. Elisa is able to
measure electric And disentangle the

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beauty component of these electrons from
other sources in both proton proton and

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lead collisions. And these is possible
because beauty algorithms have longer life

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time. So, then charge models for example,
and as a consequence they decay products

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and in particular in this case the
electrons have a larger distance to close

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this approach with respect to primary
vertex and this topological property can

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be exploited when looking at data in the
topology, you can appreciate the input

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parameter distribution which is described
with the MonteCarlo template speeds of

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different sources. In particular the red
template that is the one of electron from

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UT Adams. He has larger tastes with
respect to the green one, which refers to

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electron from charm. And these reflects
exactly the topology of dedicated there

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was explaining before. Thanks to this, we
can then provide interesting measurements

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of beauty electrons Such as the elliptic
elliptic flow of electrons in semi central

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led collisions. As you can see here, this
is a very recent result of Edison and the

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such measurements are really important for
us to have a further insight of the

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physics of beauty in the plasma battalions
can do even more and the reconstructor

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secondary vertices of charma are drones
associated to beauty Ks. And on the left

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you can appreciate a compilation plot of
production cross section of DME prompted

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the measures in proton proton collisions
by TV and on the writer the comparison of

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nuclear modification factor of both prompt
and on prompt digital mesons. All these

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measurements are possible by exploiting
different decay topologies which are

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resolved in alias thanks to the vaccine
capabilities, which are then pushed up by

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the usage of machine learning tools, which
make the separation among prom D known

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from D Background components possible.

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Looking at the results, we can appreciate
on the right plot an inter of largest

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suppression for prompted the zeros with
respect to non compliance at intermediate

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PT and these measurements are really
important for us because comparing them

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with theory we can really assess the acute
GP properties. battalion is a competitive

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experimental seen proton proton
collisions, for example, it's the only

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lithium experiment able to measure lung
the C volume down to one g v over c. EDT

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and the low PT region. region is very
important for this because here is where

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we spoke to the largest difference between
the measurement and the urbanization

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models. And in particular, the charma.
baronova measuring ratio that we measure

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shows significantly higher values, then
expectations from Monte Carlo simulations

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that are tuned to reproduce the plus or
minus measurements and these recent

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measurements from Elissa interesting
because challenge modernisation models and

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here the physics seems to hide something
really interesting. Another measurement

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provided by a less important proton
collision rapidity is the production of

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Crompton on project site, which is
reconstructed in a central Barela. Between

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in the in the decay channel a plus c
minus. The non prompt component is

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distinguished from the prompt one by
exploiting the sizable beauty decay other

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and decay length.

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And the thanks to this

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LS is able to provide the measurement of
the non projects a fraction of meter PDT

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down to one GB oversee and this is the
lowest value of terms of momentum explore

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the four DS measurement. In addition, the
measurement of Le sent me the rapidity of

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content on from chip side are
complimentary in terms of rapidity

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coverage, to the LSE v one, and this can
be nicely appreciated on the right block,

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where you can see a very nice measurement
of PCB at four feet in blue. completed by

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the Black Point from Alice. But then Alice
is able also to reconstruct secondary

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vertices associated with the case. And one
of great interest for at least in the last

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in the last year or so, is the one of the
hyper Triton became a new friend via the

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measurement of the lifetime of helium
three is very important to solve to try to

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solve the so called icon puzzle which has
huge interest in astrophysics because it

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concerns the discrepancy between the
expected values of neutrons or masses

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which is lower than the absurd one for
some cases,

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and that the three minutes again that

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these accesses the muscle is justified
according to model. So, by adding an

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additional repulsive contribution, we
should which should come from either a

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nuclear nuclear interactions and they
protect on lifetime is an experimental

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problem of this potential. So, this is
really interesting question Decent. The

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eye protection candidates are
reconstructed in a central bottle with a

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visitor finder technique. And the
signature of Viper Triton is

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reconstructing a different CT interval so
that the measurement of the lifetime is

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possible by fixing this distribution. As
you can appreciate the from the

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compilation plot on the top. On the bottom
left, you can see that the contribution of

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Alice in this field is really outstanding.
And in particular, the precision in the

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measurements for malice improved in the
last year thanks to the new lead the lead

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to data samples at fight TV recorded in
2018 and 2015 data taking campaigns.

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Before concluding my talk, I want to spend
a few words about the IDS upgrade and I

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take the chance to invite you to follow
their alley subgrade talk in which you can

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know something more about a new vertex
detector that will be available in LS

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after the long shutdown tool Which is the
newest form of tracker the IPS will have a

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renewed layout and is ready to be
installed after the long shutdown too. And

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in particular, the IPS will have an
additional layer closer to the

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introduction point. And in particular, it
will be the first large scale occupied

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monolithic active pixel sensors detector
and this will let us improve the

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performance in the reconstruction of the
flavor vertices and reduce the

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uncertainties at low PT in the performance
of this detector will improve not only

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because it will be closer to the
interaction point, but also because it

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will be lighter in term of a material
object with a reduced and multiple

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scattering property as a consequence, then
it will be faster in terms of readout and

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we Yes, we are talking about a factor 100
have improved the readout rate and then We

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will have an improved spatial resolution
thanks to an improvement. And thanks to

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this and also thanks to the further
upgrade. So that we we will have in the

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ATLAS detector, the performance of the
full apparatus will improve. And for this

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reason, we are really looking forward to
the last long shutdown and long shutdown

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free data taking campaigns. But in any
case, we can say that Ellis has been

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already obtaining remarkable results in
undoing all the collision systems

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considered. Here I report a non exhaustive
list of very interesting talks from Alice,

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about physics perspectives, I lights and
upgrades. I invite all of you to follow

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them and also the other really interesting
talks from Alice. And in general, I wish

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you very nice

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conference.

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Thank you very much for your attention.

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slot machines and questions, please raise
your hand

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don't see anything immediately.

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It is what it is ask them what they don't
see the right hand.

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I have for four speakers you can't raise
your hand but you can unmute yourself

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anyways.

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If you have a question yeah okay, so yeah,
I mean, cuz I mean your parameter solution

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is shown on page nine.

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Okay, you didn't fully understood to what
was your module.

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So what we do before constructing
secondary vertices of every flavor out on

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the case in MonteCarlo, is to apply a data
driven correction track by track on the on

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our reconstructed tracks in MonteCarlo
according to what we see in data And this

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data driven correction is useful to make
that a solution in MonteCarlo that is the

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green one originally to match the one in
data. So, the effect of the correction is

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you can see, looking at the red points,
which perfectly match the ones in data

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goes from one to kind of I mean for data
to you, I mean, this is the solution, do

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you compute the primary solution?

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we propagate the tracks towards the
primary vertex and, and we measure the

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impact parameter of prolong tracks in the
IPS and here the IPS plays a crucial role

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to these

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because we just forward for MonteCarlo
today.

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00:17:50,100 --> 00:17:55,890
Yeah, yeah. So, just a Monte Carlo
correction, reconstruct the trucks before

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reconstructing the vertices.

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Okay, thanks.

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Okay, thanks. I'm for one.

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One more quick question. No one else has
one I have kind of a related one on slide

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13 we should have a nice separation
between beauty and charm and prompt

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events. And so, I don't have a feel for
pileup at Alice, do you have any issues

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with PV Association, associating tracks to
the wrong PV.

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And yes, sir, we have about we are able to
remove a pileup sir by looking also at

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correlation among different among signals
from different detectors. And so, we

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discover through these correlations we are
able to also treated these pile up

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component. So yeah.

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Okay, very nice. There we do do something
similar for separating beauty and charm

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and lgtb this getting the wrong PV is
sometimes an issue