Yes, perfect. We can see the slides.
Good, good.
Well, good afternoon, everyone. It's my pleasure to be invited and to introduce me
to my collaborators, recent work on precision predictions, well for
differential Higgs alterable, but Norfolk sound boosted region for the Hicks
transfers moment and distribution. Okay, so first I'd like to start with the
success of our cx experiment. Recent. Currently we have the metrics property in
good agreement with the standard model, we have seen the persone kind of search
generation for non compliance is each company measured at precision past minus
10 to 20%. The Higgs mass has been measured with unprecedent accuracy at
premier level. Well the fiducial total car section as shown on the screen In the
lower part here, inside plus minus 90%. What we haven't seen is the secondary
generation from ionic coupling and the dye x signal. And we would continue the
adventure to explore the full potential of the IOC in terms of going differential in
both X production decay channels, to a set new targets for precision, and to look at
interesting fiducial regions for the future. Hi, Lumia see face hope. Hopefully
during this journey, we could accelerate the searches of new physics. Now let's
look at the Higgs production for the total cost. Share DRC. Here's the plot from the
Higgs rocks cross section working group by the ranking of the dominant contributions
start with the global fusion and BBF that we reach production. Then the force the
important contributions that are h two Higgs well the glue will also rank from
the important Friends there has been Thank you Bye Oh QC effects included xx leading
order for the VH and also an X leading order for the T bar ah all of these
production channels also accompanied by the next leading order electroweak
corrections. Now, when we move from the inclusive autocrat section to the
differential one, the current experiment measurement focus on several differential
observables for example, Hicks PT distribution repeats the leading jack PG
distribution recall from the Higgs or the N jet multiplicity measurements. So, from
these measurements, we could see below the major data point, the region or the white
region prominent by the gluon fusion contribution. The shaded area of green or
the dark shadow area are those coming from the other Higgs production channels. So,
if we want to understand the Higgs property in a good way for the bulk of the
distribution we first look at the fusion channel. So currently the experiment I
write the freshman level is about minus 20% for the series about plus or minus
10%. In general, we have good agreement between experiment and the series. Now
let's look at the Higgs PT distribution dive into more details for this particular
observable for the fusion channel. There are different theory behind the different
dynamic range for small PG region namely below 20 gV level we know that the soft
global emissions power you any perturbation can see the predictions to
cause a logarithmic divergence, the treatment is to use resubmission to
sum those large divergence to match to fix the current accuracy. So next next, you
can order metrics with cube out for the medium PT region. Namely from 20 to 200,
gv. This is the region where we could attest to the yft theory, assuming that
the energy flow into the top Quark loop, which connects gluons and the Higgs are
relatively small compared to the top mass, such that we could shrink this loop vertex
into a point like vertex. And the current procedure is the next next leading order
correction in the heavy top limit to the posterior region in terms of bigger than
200 gV, we know that the energy scale flowing into the top to open resolving or
it's comparable or larger than the mess of the top Quark. So in this region, we have
to consider the full loop dependence or namely the Standard Model contribution
rather than EFT. So this involves the calculation of the two loop community
scale diagrams by showing the lower in the right lower part and the DC A particular
challenging calculation mathematically for the Fineman diagrams. Also for the boosted
region, we would see sharply fully in statistics, why the dynamical fiducial
region this is challenging for both extremes and the theory to have a fair
estimation of the systematic error on both sides to make a reasonable comparison and
this is region also we are very interested in because the bsm models or bsm signals
potentially are involved in those large energy scale in terms of high extra
generation of quarks are optional effects from your particles. So now let's focus on
the boosted the Higgs region. As I mentioned that we need to include the
Standard Model top Mass Effect. Now two ways to look at it. One way is to expand
the complicated Fineman diagram in the variables to the region, it a few t I feel
TV The level or the energy scale is much larger than the mass of the Higgs or the
mass of the top. And after the expansion is approximation, but analytical
expansion, then we can calculate the expanded form analytically to have a
electrical result. Other ways to calculate it directly the calculation, but it's very
numerically mathematically challenging such thoughts only the numerical result is
currently available, but the numerical result would suffer from the stability for
either the high p region in terms of above one gv level. So, there has been tried
efforts to combine the two are very high PG, but still increasing you know wider
dynamic range the reliability of Siri prediction. So now beyond the technical
part of the phenomenology calculation if we look at the result, the current state
of the art accuracy is next linear with a standard model prediction from a global
future with uncertainty about the past night 20% of the corresponding
experimental measurements focused on above 350 gV has an IRA rental statistic for
about the past minus 50%. But this is not the full story. Recently, the Higgs cross
section Working Group deliver a study that just tried to focus on the posted Higgs
region and we find that the boosted Higgs PD distribution is enhanced by the Quark
PDF such that the VH production channel dominant over the gluon fusion is above
1.2 gb level and each of these two channels contributes about one third to
the total accumulated across section above 1.2 TV for the th and the V Vf production
channels are combined to the last one sort of contribution. So these indicate that to
to really have a fair estimation for What is the standard model background in this
region we need to use the joint efforts for all the Higgs production channels to
be taken into account and the to include that they are state of the art surgery
procedure.
Okay, now let's move on to the confusion channel into more details. Here is a plot
by this x cross section Working Group. Note that includes the state of our TFT
and the state of our standard model prediction, we can see that either one TV
level the two predictions are different our order of magnitude. So this clicker
means that the EFT is not reliable. However, if we look at the lower panel of
the key factor, they are remarkably similar and nearly flat at large PT. So
this could lead us to our ideal solution that we need the next leading order
standard model accuracy, but we also want the next next leading order EFT precision
So, this can be delivered with the assumption that although right now not
available, but in the future, the Standard Model predict predictions also has a flat
key effect, right the large PT. So right now, we rescale the next next leading
order EFT by region factor from the next leading order Standard Model assess the
mechanism of the EFT for the central value of the prediction. So, this is only part
of the analysis that we also need to have a fair estimation for the Iraq. This now
includes the independent scale variation of this week in terms of this region
factoring from under the next next, you know, the yft prediction on TOEFL. On top
of that we also need to estimate the missing talk Mass Effect for the next next
leading with a standard model coefficient. We can have a fair estimation for this
effect by looking at while they're lower what we missed. For the next leading order
related result compared to the full next lead in the standard model, use those
percentage to multiply the next to next lead to the EFT coefficient have a fair
estimation for the muscle mass effect. Now is this treatment, we come to the current
master prediction for the ggf channel in terms of the EFT improved one, that's
actually the order in the distribution here is showing the magenta color. So with
this best prediction, we combine the theory IRA from two sources mentioned
above in quadrature, and the reach to the theoretical certainty at plus or minus 10%
level at our next tax levy or the rebate. So now, these are very promising progress
from the state of our calculation, but those calculations are very complicated
and the neither a lot of efforts in terms of computing time Under the setup of the
code, and they are not publicly available, so to to make sure that the publicly
available tools are also give can also give experimentalists a good estimation.
We also studied for example, the simple hack i o and the medical error file using
similar setup for this boosted region. And we also match the polygon the middle
result with PCL six puddle shower to also include the puddle shower effect. So, the
results compared with the current best is quite promising. We see that the mean on
the Minecraft five result has a central value in good agreement with the
corresponding surgical arrow with the current the best under the current or past
has about plus 20% correction to the central value while the uncertainty is
reduced from plus minus 20% or more to plus minus 10%. So a reduction of more
than or roughly about 100% From the theory perspective, so this is then I mean very
useful information that you could still use perhaps me or Minecraft, including the
Mass Effect optimax linear models with pattern shower and now to mesh to compare
to the current events, there are some key factors you can extract from those
analysis and to enhance the accuracy of the standard mode background.
Okay, so as I mentioned before, this is only one third of the full picture for the
future. We also delivered a study for the vH vpf and the TT Rh contributions also
including the electronic fractions your social class or group and here is the
result for the full combined Higgs production at high PT in the black curve,
and with the different production channels coded in different color and this is an
Under actually with result I showed before for the fraction contribution for
different production channel that the claw fusions actually get less and less
important that the VHP kept the dominant position okay. So, now more quantitative
analysis for the contribution between different production channels, we could
see that the dominant scale or scale uncertainty is currently still coming from
the ggf for the current best and from the TT batch at about the plus or minus 10%
level, the reach production is getting more and more important at large PT and
the corresponding and actually they will do something about 5% and actually the
state of art calculation not included here, but is already available at next
next leading order indicates a further reduction of scale has certain down to 2%.
So, this is actually a question Under a very good control, interestingly to notice
that although the vbf scale uncertainty is the smallest among all the four channels,
but it's increase gradually from low PT to high PG are the other channels.
Theoretical uncertainty is basically the flat. And on top of this, we also need to
bear in mind that the electronic corrections are substantial. We don't have
the prediction for graph fusion a channel for the electronic corrections yet, but by
looking at the dvh production channel for the electronic correction can be as large
as minus 30% at a large peaky region above the TV, so this has to be taken into
account. And so with all this information is not aiming for, I'd say this is the
result you should use but to just remind us that the new physics effects could
affect the virus China's differently that we read. recommand to use simplified
simplified template cross section to reconstruct or classify each event to by
their production channel. And to understand what's the corresponding
compensation factor we should use to have a fair estimation of the standard model.
Okay, now let me come to my conclusion that the Higgs boson precision
measurements focus on differential observables and the distribution in
production and the decay channels. The corresponding predictions focused on
reducing uncertainties from or sources for example, fixed order correction actually
correction potential effect, etc. So the boosted Higgs is becoming the focus we
improve both experiment and see reposition to accelerate the searches for new
physics. And the Higgs properties is quite different in the boost integration time
the bulk of the Higgs production car section currently the red coin certainties
under control I took about a 10 to 15% level for Expedia 400 gV patentee are
several new sources of cereal and certainly not included in this quarter. In
terms of the top master scheme choice, which is substantial linear order should
be considerably reduced when we go to higher order this would affect the top
mastering the full Standard Model looping group, or the top mass used in the DFT for
the Wilson correction. Also, we haven't included the PDF and the company
uncertainty in the 10 to 15% quarter, but we believe it can be systematically
improved in the future from the efforts of the PDF group are fitting with more
precise data from IFC. We could also do a better job in the future to rescale for
the mass atomic mass effect in the global fusion channel event by event rescaling
manual right now is a histogram level. And we also plan to upgrade the VH and the BB
if predictions to include the next time leading order items you buy state of the
art accuracy to have more control of the answer today, especially for the VH
production channel. Thank you.
Thank you very much. It was very interesting. We're a bit over time. So
let's take questions from the audience.
Giovanni please. Yeah, I was wondering So, the uncertainties here, this finger is
essentially for to Sydney and then we should and we expect to the the to show
that somehow the also the electroweak part or on you know, if this is the case so you
know, when we could also improve these estimates to add those to the estimate of
the electroweak
Yeah. So, yeah, so this 10 to 15% quota, it's basically this table combining okay.
So in this highlighted region combining those uncertainties together for
estimation in quadrature for fair estimation, but these are mainly from the
QC the corrections the scale variation, the missing high water effects beyond the
current nominated fixed older, yeah. So, this part, we we were kind of assuming
that the was the dominant uncertainty level is still kind of quite important
from the confusion channel and the electronic corrections that the we have to
include a correction for sure, but the corresponding uncertainty mean we need to
add this minus 30% to the VH channel? No too little for the central value, but the
response theoretical error is not as significant as the QC dx certainly here.
So there are like so it's kind of the, say the the systematic theory error due to the
components we forgot to include. That's one big correction. The other one is once
we include everything, because of the fundamental problem of quantum field
theory in the perturbation theory, still some level of uncertainty here we will not
be able to go beyond and that's that's kind of the bottleneck part not have to
rely on the higher order corrections or more detailed resubmission study. These
are the kind of the quoted error I have here for the 10 to 15%.
Thank you, my friend, we need to move on quite quickly so let's
let's thank axon again and let's