Nikolas shanell he will be now talking about rare top presses in CMS.
Thank you very much. Do you see the slides? Yes, we see the slides and we see
you I should probably first canceling. Yes. Okay. Thank you very much. So, yeah,
I will present the the same, the same processes here, stock processes. But this
time the measurement that we do at CMS and the outline of the talk is the following.
So, I will present some two measurements. For those processes. I will start with SR
plus d, then also for the SR plus gamma and on Monday, and then there will be two
flavors of foster community analogies, and the plot shows the production cross
section For different processes, we've stopped clocks and you can see why we call
them overhead processes. Just the fact that there are three orders of magnitude
between TT bar and TQ or TMS Q and two more orders of magnitude for photo. So
these are really rare causes. So why do we want to measure them? Obviously, if you
can first observe them, which is the first goal, this will constitute this test of
this phenomenal prediction. Especially better but if GCD but also a little weaker
correction. GTC Q and T, gamma q processes are electroweak produced and they have
some features associated to that. And also, default of processes are mainly QC D
induced. So it's not exactly the same kind of couplings you're probing. However, what
is the kind of connection between those three processes is the fact that you can
prove The top was uncoupling. So Tz Tz Joo Yang began actually with muesli. But
interestingly, you can also probe the Higgs top you can walk up in the photo via
the, the actual diagrams. And you can use all of the three processes to measure two
sets of possible deviation in the precision measurement. And then it's
sensitive to new physics and you can for instance, could result in the framework of
the effective sheet theory which I will show some of them. I start with the singer
topless the analysis performed in the 3d Tom final states with 2016 and 17 data
with relatively low PT of the leptons and obviously you also require to have to have
the leptons of same flavor but it's sign and fitting with z. z was on April This is
so as I said, this is a recording produced. So this has the feature of
having a fallout jet. We go to 4.7 supernova PDT and you can use this fact to
discriminate signal from back on you have on the bottom left an example of
distributions here are the recurring Jetta showing that indeed around two or three in
pseudo IPT you have increased the signal of a bad comment. So that's quite
interesting. A very nice feature of this analysis is the fact that we work with a
lot on identification with ability on the plot the blue triangle is the is the
little ad efficiency in the previous iteration of the analysis, which has the
which which are heavier than evidence and in red and black, you have the new Working
point, you can see that first of all, you have an increase of efficiency now you are
more than 90% for each return strategy, and then the background is reduced by a
factor of four better. So, this is a huge
but still the same, when even if you reduce it, you need now to estimate this
non combat on residual, which is made of basically TT bands projects. So, we use a
fake rate method, we estimate the fake height in our TCGA data, we've loosened
the leptons selection and it's applied in sample we basically you applied the
selection but you you loosen the criteria and Sati percent uncertainty the same. We
also have to control agents for the diversions and for the signal extraction
we use three different categories in news feeds where we use the be some validity
discriminant So, the first region on the left panel It shows the region with where
you have two or three digits among which one digit, it constrains mainly to the
queue as well as our processes, but for TTC, you would have to go to detours
origin which are four digits among which one digit and as well as two digits. And
if you fix maintenance lead the three regions, you would get the results shown
on these slides with a measurement of the cross section agreeing with the Standard
Model prediction and the significance for observing this process is now 8.2 sigma
observe while it was 77.7 expected, so the process is observed. The main
uncertainties here are the non comeback on the JT energy scale it on efficiency
finance the stabilization Institute to scan uncertainty which are the tools as
being related to the modeling and 3d modeling and you have to fully released
the details here, I want to attract your attention on the fact that if you plot the
PT of the symbolism for high values of the BDT you have plenty of events and this is
quite nice. So, now this measurement is made much for differential measurements. I
move to the next analysis which is SR topless gamma performed in the immune
quantity channel with 2016 data to jsoc requested with one tag that digits the
dominant background is dt plus gamma as you can see in blue on the left, there is
also in red, quite some residual background arising from non POM photon and
which is mated with the fake ratio methods where you'll be like different equipment
and usually query to miss identify a nonprofit As upon photon, I forgot to say
that the plot also shows the fallout jets suitability, which is a very good valuable
to increase the discrimination in analysis perform with ability the ability output is
shown on the on the plots on here and indeed default is one of the most
important viable the analysis the extraction of the signal is performed in
the following way. So, there is a template for TT plus gamma, which is a one of the
main backbone is obtained from data in a consolidation with an additional digits.
And you do then a scimitar newsfeeds of the signal to McHugh and also of gamma. So
this led to the first evidence 40 and IQ we've been obsessing if she comes up 4.4
sigma. Well, three sigma was expected and the measurement is already dominated by
the systematics. Genetics can be taking in signal modeling, you can see that within
the uncertainties the predicted cross section is in agreement with dimension. So
I move now to the to less than many this which other photo up and I start with the
first let's say flavor. Where definer states state analyzed has one Lipton or
two leptons of opposite sign. This analysis uses 2016 data. And the strategy
here is to go in the region where there are a lot of jets
because among the top stays on one or two deals are just decaying jets. You can go
to the seven or eight jets region require you have a loud HD of 500 gV. And for the
daily tone, you can go a bit lower in the number of jets. But but this is still the
same kind of strategy. An important ingredient here is the atomic
constructions you minion dogs it's the one with the BDT train with the good let's say
the right assignments among old user facility for Justin that damage arising in
fact from the corrections are needed. So, you see that here most of the time the
background is is a TT ba. But and you are in the region with majors so you not know
know exactly what what's going on here for the signal that you have never measured.
So you need to correct for that and you go in a high jet multiplicity in Region One
Laptop and you can measure a basic scale factors and correct the signal with this.
You also use the sorry the dedicated measurements of teaching me another
measurement existing performance you miss frosty back recipe. And do so, this
component is easily rated using using this measure not at certainty the strategies to
categorizes the number of jetan digits that you feel that is shown on the left
some and even BD T's are constructed four different kinds of agents which are shown
on the on the right using the scarf or the other the tiger many as many drivers of
different times in some valuables formulator and sorry, electrons in the
beaches. results for this analysis are shown on the table. Basically combining SR
and dialects on you can only exclude cross section written and 5.7 times the standard
ngmodel alone. But if you combine with me tips on this goes to effect of sorry to
vote Two times the standard model and politics to the senior sense that you
could measure with the media on analysis alone. I'm speaking to you about the media
companies performed only 16 data, then adding this one little two little sign
improved by 10% and I will show on the next slide, what what became the regional
plan is when we included the fluent So, still here on the one intellectual
autonomy sign, there is a interpretation which is going on if it's up to E. You can
constrain the four Kwok behaviors in dimension six you do some assumption
especially you you want that to those those operators are impacting just surgeon
ation quacks and he just found out the assumption in the DMC stuff. You neglected
to review characters because they do not to be kosher and once you assume
kinematics of disarmer then you can derive the limits on the measured cross section
on the four operators here and you will meet between two and eight t to the minus
two on G with some coefficient. I move now to the last analysis which is the fact
that in the muted tone, by muted tone we mean same sign dialect on or greater than
street it on final states. The function with full on to data against you there is
allows me to PCT a bit less than in the one little two little case and in the
background is different. So previously it was basically TT bar here you can see in
green and bluish gray, that it will be teaching w NT th we've also non negligible
nonpoint back home. The strategy here is to use a multi layered classifiers While
in the previous iteration of Genesis we were just using the code base, which is
each of us as
classifying the events in the law of latency jets and the Jets. We've to
control region for the TV back on this estimated with some collections also from
data. So ASF is a collection from teach about the ties applied to w z simulation
tvV already jets collection visiting in 70% increase in addition it is applied to
teach h w and Z. And then as standout in unmuted on analysis, there is a chart
misidentification background estimated from z data when you flip the chart of one
of the lips on and there is the non complete from Viacom estimated in a way
similar to CQ analysis. We've estimated in the competition On the status of chin,
there is the possibility distribution showing showing nice agreement between
data in general and the observed significance here is a 2.6 sigma. So,
gamma from sweet G's beta is very close in agreement with the Standard Model
prediction of an electricity Pacific. You have on the right the full list of
systematic uncertainties among which the main ones are jet energy scaling
resolution be tagging and of course, the modeling with the turbine is
last.
Yeah, last slide basically before the conclusion is interpretation that we do
with those measurements and important interpretation is related to the topic
sculpting. So, we can also measure it here as I said, using the actual diagram It's
complete one tiny tweaks measurement also not as quite as precise in the result is
shown on the plots and we reach basically Cataclysm done 1.7 95% confidence level.
So, this is this is this is very interesting actually, you can also do also
interpretation like the measuring the person object parameter, which basically
modifies within the framework of EFT. It will modify the Higgs boson propagator and
also coupling to clock in lectins. The value we obtained here as a result is
compatible with your own sensitivity that you could get from off Shilajit
measurements which is interesting. And there are many other interpretation
available in the paper related to dark matter. Two is a bit muddled or h&s isn't
it? coming to my conclusion. So, for those processes, I have presented your
observation of acuity, five messages, remaining improvement in the electron
identification. And I think we will soon go into differential measurements to an IQ
has first evidence and observation is the next obvious goal for the photo cracky see
quite difficult, but we are nearing evidence and we saw that address best
threshold and we can maybe hope foreign observation maybe this is very sensitive
to new physics and I think these interpretations have something to be
pursued. And I have noted here the room Zoom Room for current discussion with
addressing CMS if you want to discuss the contents of your question.
Thank you very much Nicola. So now we have some time to ask questions. Please raise
your hand if you have questions for Nicola.
So we have time for a question.
Okay, I have I see one hand, okay. Oh, now I see to first Francesco.
Introduce yourself once more, please.
Yes, thank you, the Francesco Spano again from Atlas. I have one question more
curiosity in for your one left and opposite sign.
Do you remember I know it's a very complex analysis with lots of inputs and difficult
subtleties and the multi lepton. But do you remember the impact that pattern
showerhead ization has in in the shower and head organization hasn't been analysis
and how it is treated? When you have large number of jets?
Yes, it must have an impact. I agree. For the precise quantitative statement is
difficult for me and I don't remember. Yeah,
I agree. It shouldn't be. It shouldn't be something important. I don't know if
somebody else would like to.
I guess not.
So I see no one raising a hand too. Jimmy
will then to the next question
I see one
please go ahead yep
yes yeah this is similar on this from Atlas.
But then to apply and W crease extract jets for your daughter something like 300%
plus j h eight jets and since you saved for me to leptons you apply some
corrections for a cipher Sir, do you know what is the order of magnitudes of these
equations applied form Do you proceed or extra jets and it's the same order of
magnitude of uncertainty and plane in HS
I think it's not it's not like the BB on It's not 70% I think it's less but Okay,
so here I should I should say that I don't know may have the exact number but you
should be able
of course we would like to hear that it's 30%
I'm not sure
I'm not sure that those 30% that we see in many analogies arise only from to city
basically. And so I don't know if it goes I don't know the precise number but but i
i wouldn't be surprised or that just just so it's exactly 30% 10
Okay, just to say that cuz it's not super sensitive, very conservative, very
separate don't expect it to be at the same bedroom. Yes, as an actress, but yeah.
I mean, we have seen the certain percentage Elsewhere in CMS CGH analysis,
you know? So yeah,
you talk about the 30% certainty on multiple platforms, right. I was just
relieved The question was on teaching w basically.
As far as I understood not only D uncertainty, but you take the correction.
The scale factor.
I think they do have a control region for remember.
Yeah, so I checked that in the trip based analysis.
There is a TT WP Engine. And if you look at the number of events, it's slightly
above in the data relative to the Monte Carlo, but it's like almost Yeah, maybe
even 5%. So I made my guess That is a correction algorithm most of the job to
move the sequence things of tGwU to basically to one in data. You have to push
it. I mean,
now,
is it the only reason of this agreement? What No, sorry, is it the only reason why
is it the only reason explaining this 1.3 factor? I'm not sure. But at least once
you correct yourself, so, you you you go to an agreement between t GW predictions
in the simulation and what you get what you have in this control.
Okay, um, are there more questions for Nicola
and we might have one or Okay, I see one
But that's from I just got a new new question and or Okay. All right. Yeah.
But we have maybe a minute or so, to if anyone has questions to the previous
talks. In principle, we should have some time at the end of the session. We don't
have a lot of time, but one or two minutes if there are questions.
Okay, I see none.
Then I suggest we close this session.
So as you all know, we have another two