Giacomo Ortona: Okay.
Giacomo Ortona: we are starting to record, and you should just have gotten a notification from Zoom about that.
Giacomo Ortona: Again. Thank you all for joining us. Mikheila. I guess I think that you probably have some introduction, or you would like to introduce the arguments in any case. So
Giacomo Ortona: unless Danielle and Ken would also like to make some initial remarks, I would leave the floor to Michael. And this presentation.
Michael Duehrssen: Can you actually hear me.
Giacomo Ortona: Yes, we can hear.
Michael Duehrssen: Okay, very good. Now, I just have to figure out. Do you see the slides?
Giacomo Ortona: Yes, it's not full screen. But for me, it's okay, I think. I think it's okay. We can see them very well
Michael Duehrssen: in principle, should be full screen.
Michael Duehrssen: Is it still visible now. Yes. Now it's full screen. Yes. Okay.
Michael Duehrssen: okay, very good. So this s. 6 s. And Hixdy case is a a topic that has been in discussion in the mid working group
Michael Duehrssen: since now almost 10 years, or at least doing something for the case.
Michael Duehrssen: But I think a topic never managed to really get off the ground.
Michael Duehrssen: So here's another try to to get it forward with practical proposals.
Michael Duehrssen: So just ray basic, the goal of doing hex decay measurements is to provide inputs that can be used for theory interpretations
Michael Duehrssen: and similar to the productions also there for the Sec cable. we should likely do 2 stages.
Michael Duehrssen: stage 0. Where we actually move from the current measurements of Stxs that have includes a fix. The case.
Michael Duehrssen: The people sometimes forget that Sx
Michael Duehrssen: is not only production mode. It also defines that on the decay side we just take branching ratios or ratios of branching ratios.
Michael Duehrssen: and the experiments measure them as well. but they sort of take a sub leading role because people tend to ignore them. But we do actually measure the inclusive fixed decays in a success.
Michael Duehrssen: But they're inclusive.
Michael Duehrssen: while the experiments don't necessarily measure the inclusive phase space for the decay. So what we measure and what we on the theory side use do not agree.
Michael Duehrssen: So what we first need to do is define is stage 0 for the decay, meaning for each decay mode.
Michael Duehrssen: We need to define an approximate phase region
Michael Duehrssen: that is close to the experimental acceptance. So on the production side, this was the rapidity cut on Hicks of 2.5
Michael Duehrssen: on the decay side.
Michael Duehrssen: You'll see today in the example. Fix for that. So this will be, for example, some mascots.
Michael Duehrssen: and then at a stage one, we would then define properties within each decay mode that one could use measure and then use later on to constrain Bs M effects.
Michael Duehrssen: Okay, so the first thing is just to why do we need to stage 0 and species is that this experimental measurements are not inclusive.
Michael Duehrssen: Up to 2, 3 years ago this was mostly in a theoretical example, work or something where we just argued, but didn't have something to show.
Michael Duehrssen: By now experiments have made first measurements and tried to do EFT. Interpretations of these, the S sticks as measurements. and actually have seen that they are sizable problems. So here's an example.
Michael Duehrssen: the in the Hicks disease measurement of Atlas. He has a distribution of the
Michael Duehrssen: mass of the second sub-leading Z boson, the reconstructed mass you see in the standard model. This is a raising curve, and because of various standard model backgrounds, we do a cut of M. 3, 4, bigger than order of 10 GV.
Michael Duehrssen: And for the summer model this is not a problem.
Michael Duehrssen: We basically then extrapolate from the experimental phase piece that we measure. So this right part of the curve.
Michael Duehrssen: Only this small bit to be inclusive.
Michael Duehrssen: So it's actually not a big issue. However, once you go to an EFT model.
Michael Duehrssen: you see, some of these eft bottles have actually the majority of these events in the the region where the Lepton Lepton invariant mass below 10 Gb.
Michael Duehrssen: If you then apply the same extrapolation factor from the standard model. To these eft models you get a complete bogus result.
Michael Duehrssen: and that leads to the lower plot, where you look at the acceptance of eft models as a function of some eft parameter. And you see this acceptance is not at one. As you would like to travel in a real measurement.
Michael Duehrssen: It has a strong dependency.
Michael Duehrssen: The solution, the experiment zoofy used is they and introduced EFT. Model dependent acceptance corrections.
Michael Duehrssen: But then it's hard to really call that a measurement. And so the idea would be to now define a way
Michael Duehrssen: for the istigs. S. Let's say, decay volumes to match closer experiments, so that we get this acceptance back to one
Michael Duehrssen: and can really make measurements that are model independent. I'm taking here eft as an example, because for if we think of Hicks decays. The Q squared is really fixed to 125 gv.
Michael Duehrssen: so we actually exactly know what's happening. And there is not that much. And extra physics that can go in.
Michael Duehrssen: So EFT is actually a very good approximation of all kinds of BSM. That could happen
Michael Duehrssen: in each case there is still a small exception that you can have ray light particles entering sounds like a Higgs, 2, a a. To several Leptons
Michael Duehrssen: that would be not covered by EFT. But almost all other kind of new physics would fall in it. So it's a very good benchmark to check
Michael Duehrssen: whether an improved s. 6 SDK, definition actually works and helps.
Michael Duehrssen: So this comes to the next big, important point is Lawrence invariance.
Michael Duehrssen: When we measure or want to measure Higgs decay properties. These measurements should be valid, independent of the expedition production mode.
Michael Duehrssen: and independent of what kind of Pt. You Hicks got
Michael Duehrssen: right. We don't say we measure Hicks decay property under the condition that the Hicks was only produced in fluent fusion. That somehow doesn't make sense.
Michael Duehrssen: So we want to have this property measured independent of Higgs production independent of boost, it should actually be the same whether we have Lhc. A. 7, a. 13, 1, 6, or 14 TB. It should still be the same. Once we move to an E plus e minus collider, that should really be a universal property that we want to measure.
Michael Duehrssen: Fortunately, on the theory side, the hixes has been 0. Particles of production and decay are completely decoupled. So it should be possible to do. However, if we really want to go, that an absolute essential requirement is that we define
Michael Duehrssen: any decay properties in a Lawrence invariant way. If it's not Lawrence invariant, it can never be independent of the Higgs production mode, its boost and many other properties.
Michael Duehrssen: So our task is now getting a bit more difficult. We need to make for each fixed decay mode. We need to make a Lawrence invariant, simple, fiducial decay selection that means especially the let's say, the most formal cuts that people think of, and they think of fiducial selections. Things like Leptin, PT. And rapidity cuts
Michael Duehrssen: you can't do because they are not Lawrence invariant. So we really have to rethink a bit how we do our selection and still match them actually with experimental selections
Michael Duehrssen: that are really definitely lab frame dependent
Michael Duehrssen: as a byproduct. If we go this way, we actually will also get a clean definition of what we mean. For example, if you talk about H to Z or H. To Www.
Michael Duehrssen: So far, people, if you say Hicks to Z have sort of a certain concept in mind what that is, or if you talk about Hix to WW.
Michael Duehrssen: And this concept is mostly related to what kind of Pisa decay mode you need to select to gather decay. But in reality physics is a bit more complicated. Just think of something like and you and your final state.
Michael Duehrssen: So Higgs, WWW. If you go to the laptop mask close to 90 GV. This could add, well, be hexa z, where one z goes to 2 leptons, and the other goes. Z goes to 2 neutrinos.
Michael Duehrssen: So we have actually there quite a lot of crosstalk, and it's even stronger if you think of some modes like Gamma Star, Gamma Star. Whereas what is Z? What is Gamma? Gamma? Gamma star? Gamma Star? It's actually not well defined, and
Michael Duehrssen: this is somehow misty. We don't have on the theory on our experimental side a clear definition of what are actual decay modes at a position we might need. Once we go to present level
Michael Duehrssen: results. So this would hopefully come as a secondary output of this effort.
Michael Duehrssen: Now.
Michael Duehrssen: going a bit back, it's actually not quite as complicated as it as this may sound. Most 60 Ks are actually two-body decays. and since the the Higgs is a scalar, we can always go to the rest frame, there's actually no information transferred from the production
Michael Duehrssen: and the rest frame. 2 body decays are also always back to the back. That means for 2 body decays. That's actually no kinematic information at all contain the decay, meaning you can't even do a decay measurement right? It's just basically the branching ratio or partial width is all the information there is. So for these ones. We didn't still want to have some fiducial object definition. What is a photon? What is a Lepton? This kind of thing? But we don't need to do anything else
Michael Duehrssen: right? So all of these
Michael Duehrssen: should be in question. Sort of simple in some form. In some case it will not be so. Have some sets as simple. If you think of fix 2 dB.
Michael Duehrssen: And want to make a fiducial definition of what are what are B jets? It will get complicated again. But we can skip that for to day.
Michael Duehrssen: So but after that means the only non-trivial decays today that we have is something like Hicks to Z. Gamma Hicks, to WW. To L. Nu and Hx. To 4 laptop.
Michael Duehrssen: and from these seeks to Forlepton, is actually the highest priority.
Michael Duehrssen: because, as shown before in the motivation. The current measurements are already quite affected by this tension
Michael Duehrssen: in the Aztecs unfolded, because between the experimental selection
Michael Duehrssen: and that our definition of the decay is inclusive in Sds.
Michael Duehrssen: So the goal for today is that we have presentations from Atlas and Cms on let's say first candidates for Lawrence and Varianson.
Michael Duehrssen: Simple fiduciary selection takes the 4 laptop
Michael Duehrssen: the target. How these selections were built was to make the
Michael Duehrssen: fiducial selection
Michael Duehrssen: in some way larger than the experimental selection, meaning that almost all the reconstructed events should be part of the fiducial events.
Michael Duehrssen: You don't want end to end up with this definition.
Michael Duehrssen: where half of your reconstructed events are not part of your fiducial volume, because then you actually measure something completely different than what your theory says. On the other hand, the
Michael Duehrssen: the Fiducia volume should also not be too much larger than the experimental selection.
Michael Duehrssen: because you want to design the selection such that
Michael Duehrssen: it is, has a similar efficiency with acceptance for the standard model
Michael Duehrssen: and Bsm interpretations. And for the Bsm. We take here the eft models as a as an example to show that they actually have similar
Michael Duehrssen: acceptance.
Michael Duehrssen: And then the third point would be thinking a bit more of the future. After you've done the stage 0 for the stage one. You want to pick a property to actually get information from the decay. The ones usual that people use is, for example, the mass of the Z second Z, where you can. I nicely see here, it has lots of discrimination power.
Michael Duehrssen: So you would want to measure some bins. Let's, for example, say in m. 3, 4. In order to do that, you would have
Michael Duehrssen: again warned that standard model and the Bsm. Model have a similar acceptance in terms of this observable, so that you can actually make a measurement, and then later on, interpreted in Bsm models.
Michael Duehrssen: If all of that effort is successful, then the ultimate goal would be to change what Atlas and Cms. And then also the theory called Hst. Instead of using just the inclusive hex disease as Pissier does
Michael Duehrssen: we would want to use, say, Hixy Z is now for Lapton events within a certain sympho fiducial decay volume that is suitable for future interpretations.
Michael Duehrssen: And.
Michael Duehrssen: as basically it said before, it's this is the beginning. There's a certain simple write app that I cannot attach to the agenda. I have sort of forgotten as well do it in a few minutes.
Michael Duehrssen: But this is definitely not final, and in many cases not even well developed. So feedback is needed, and definitely far more studies than just the 4 laptop we'll see see today.
Michael Duehrssen: That's it.
Michael Duehrssen: Are there questions or comments?
Michael Duehrssen: And are people still around?
Giacomo Ortona: I see there is a hand raised by Andre.
Giacomo Ortona: Please, Andre, I think
Giacomo Ortona: you are the only one with a handwriting. So please go on.
Andrei Gritsan: Yeah, thanks.
Andrei Gritsan: I was trying to understand what it means in practice. Lawrence. Invariant selection, log detector is not Lawrence invariant? Right? It's a laboratory frame. It is not possible to have Lawrence invariant selection.
Michael Duehrssen: Yes.
Michael Duehrssen: I mean, if I fully agree with you, this is then sort of the tension we have to work out that he want to have a selection that is loser than the recon selection.
Michael Duehrssen: So you will select more events, but still sufficiently close. That stunner modern BSM. Behaves the same way.
Michael Duehrssen: If if we hadn't the restriction of Lawrence invariance, we could just use the fiduciary selection that Atlas and CMS. Already have for the differential unfold for Lepton measurements.
Michael Duehrssen: This one. Actually, they were really nice. I mean, they have basically complete flecked acceptance between reconstruction and fiducial volumes. But they are not Lawrence invariant.
Michael Duehrssen: There's some way they're too too good. They are really nice selection, but they are not Lawrence invariant. That means, if you would use these elections.
Michael Duehrssen: any decay measurement would depend on the production mode, the production boost.
Michael Duehrssen: and then it would not be universal quantity you could quote.
Michael Duehrssen: you could not say the partial wis of 4. Lepton. In this phase. Space is this number. It would depend on your on your on your production. Mode. Motivation is very clear. I'm just talking about practical things. If you are sayingial selection is loser than our detector, then
Michael Duehrssen: let me give you the Lawrence and mine selection. No cuts. That's the Lawrence and Marian selection. It's loser than what we have on experiments. Exactly. But but no cuts.
Michael Duehrssen: as you see, goes, goes, doesn't work.
Andrei Gritsan: Yeah. But but but if it usual selection by definition, is something tighter than what is an experiment?
Andrei Gritsan: If you get something loose, that there will be some events which we later cut all by detective effects. So you cannot eliminate Detectivex. You're saying you want to reduce the detective effects straight. That's the next 2 talks right? They will show where Atlas and Cms stand. With this effort.
Michael Duehrssen: Actually, for for Lapton it works surprisingly well.
Michael Duehrssen: I think the the next challenge after for Lepton would be the H. To WW. Where we are far more detective dependent, and then picks the 4 laptop.
Andrei Gritsan: But but still be before we go into details, I want to understand the concept. You want to reduce the effect. You don't want to eliminate the effect, because if your selection is loser, but if you knew something will be detective effects on top of that right? There will be detector effect. The thing is the detector effects. Now we come into the fine print. You don't need to eliminate detector effects as long as you can
Michael Duehrssen: do the selection. Such a way that the detective effect work on the standard model in the Bsm. In the same way.
Michael Duehrssen: Well, that's almost not possible. Again, it's a it's a degree to which you are affected. So it's not possible, but it's possible to certain degree, it's to certain degree. And I mean just I can't give you, for example, one simple example.
Michael Duehrssen: If you think of the Hicks. Rapidity cuts
Michael Duehrssen: right. So lectin rapidity cuts of 2.5 right. This would at at first step. You would think this is a killer argument.
Michael Duehrssen: The thing is, the Higgs decay is is full pisometrics. There's no preferred direction. So somehow both standard model and EFT. Were completely average over all angles. So in the end.
Michael Duehrssen: I mean, that's the next talk to see. But it's these rapidity cuts where Lepton cuts are. Not that crucial
Andrei Gritsan: in general. We are lanky in the full up and decay. That Dk is a tropic. So in that sense acceptance for Glian fusion or acceptances. With bf, they're different. But they're drastically different. I think that's what's that's what you are talking about.
Michael Duehrssen: Yes, but it's also be inside the decay kinematics. If you go to a Bsm model inside the decay. Even then the acceptance with and without for this rapidity cuts on the Leptons is not drastically different.
Andrei Gritsan: Yeah, I guess what you're seeing. Let's see the next talks and see what happens. It's this next talk. But of course, I mean.
Michael Duehrssen: there's a certain goal, right? I mean, you don't want. If your experimental precision, let's say, is 10%.
Michael Duehrssen: You don't need agreement to the subprime level
Michael Duehrssen: between your fiducia selection, the rico selection.
Michael Duehrssen: Right? So we'll have to play, and I expect not for Z, but for other people. Modes. I guess we have to find what is the good.
Michael Duehrssen: That's the intermediate solution between making it model independent and still keeping it. Lawrence. Invariance, as we actually can make a measurement that has a universal interpretation as a decay. Property.
Andrei Gritsan: Okay, that motivation is clear, then the other question.
Andrei Gritsan: like in other cases, let's say, if the usual or differential distribution, Delta 5, we are not trying to make something which is Lawrence invariant or mode invariant.
Andrei Gritsan: you still can interpret it. It's useful measurement. But the same thing here. Do we really need to go to Lawrence and variants
Michael Duehrssen: we can have. Yes, you have to, because I mean, there is. I mean, there's the one the arguments I've just given you one part of it. But there's also a practical argument. If you go, let's say, assume
Michael Duehrssen: just as a single simple example. We want to measure 3 bins in M. 3, 4. Okay. if you measured lawns invariant. and you also might want to measure, let's say, your 30 something. S. Tx production bins
Michael Duehrssen: the number of degrees of freedom you have to measure just adds up because a completely decoupled slorin is invariant. You can measure the same M. 3, 4 in all production bowls and all bins.
Michael Duehrssen: So instead of, let's say, 33 production
Michael Duehrssen: modes bends. You measure, then 33 production, plus 3 decays, or in the end your 36 degrees of freedom. You want to extract from the data.
Michael Duehrssen: if you don't make it, Lawrence invariant.
Michael Duehrssen: the number of bins multiplies. So you have your 33 production bins times 3 decay bins. So you have 99 observables to extract from your same data.
Michael Duehrssen: It's really it's if you, if you don't make it, Lawrence. Invent production in decay doesn't factorize.
Michael Duehrssen: and instead of measuring these independent as observables, you have to measure the product of them.
Michael Duehrssen: each decay observable in each production. Bin
Michael Duehrssen: the same as you currently do in fiducial measurements
Michael Duehrssen: we measure some most times one d. Sometimes 2D. In gamma gamma, we manage to do correlations between them that we can actually correlate 2 measurements.
Michael Duehrssen: but they are not independent.
Andrei Gritsan: So let's see, next talks, how in practice it goes.
Giacomo Ortona: Thank you. Are there any more questions right now for Mihail? Otherwise. I think
Giacomo Ortona: we can proceed with the test made from others and Cms
Giacomo Ortona: in any case. We can continue to discuss after this. After there, this 2 sets of slides.
Michael Duehrssen: That's just one quick comment, at least for Atlas.
Michael Duehrssen: because of approval procedures, since sort of we know that these selections are not final because we need to find a compromise with Cms. The slides are not uploaded to the agenda. They're just shown here.
Michael Duehrssen: because stuff will still still change.
Giacomo Ortona: Okay, But then, is it okay? If we record the meeting. since we are showing the slides. What is the what is the rule here?
Michael Duehrssen: Nicola connected? I defer to higher powers.
Nicolas Berger: Hi! Yes, I think it would be probably better not to record for the reason that Michelle said that we don't really want this part to be anyway recorded for posterity, because it will change, probably quite soon.
Nicolas Berger: And also, yeah, because of bureaucratic reasons. So yeah, sorry for this. Okay, so I will stop the recording
Giacomo Ortona: and then we resume it for? The for the questions and for the Cms results.
Giacomo Ortona: is it? Okay? Let me just 1 s to find the button here.
Giacomo Ortona: Okay, so we are online again. Speaker. So I have
Antra Gaile: no introduction site and going straight into the changes that we can make for the official selection on the left is the column of our run, usual selection, and on the right, with the things that we have changed.
Antra Gaile: keeping in mind, keeping in mind that we wanted to be as close to as the Atlas bolded, or the things that are the most difference
Antra Gaile: and just not shown in the next slides. But just to mention that the record selection is, as in previous 1, 2 analyzes talking about these 2 ratios, where the first is events that have a construction with respect to all that happen selection, and later on the second or kind of the efficiency
Antra Gaile: will be the ratio of construction. With respect for to see what for
Antra Gaile: these events that have been generated construction
Antra Gaile: and the combination of past transfer instructions and video shows.
Antra Gaile: And just let me point out that so all 4 shown will be in the Gen. Level, observed.
Antra Gaile: Okay, stunner. turning into the ratio f meaning with respect to everything that had passed the fiducial selection.
Antra Gaile: We also don't see a flat distribution, however sort of
Antra Gaile: they are so independent.
Antra Gaile: On the left we can see if it is a normalized, while on the right if it's absolute, and in our case, during the ratio respectable, that have passed, the fiducial selection is around 20%. Or or a bit less
Antra Gaile: morning
Antra Gaile: to another variable. The same ratio just showing this, for that goes with the star second on the left. If it is normalized on the right, if it is the absolute values
Antra Gaile: and jumping here into more plots with again the same variables overall, we can see that
Antra Gaile: independence. It's not necessarily flat. There are some minor details and second things that do not overlap perfectly. So perhaps I could start to the discussion
Antra Gaile: going later on for the other ratio, and then, if, in the case of apples, he managed to replay the efficiency above 99 for Cms. With these cuts, we don't have it as high.
Antra Gaile: Here are 2 examples on the left for set, one mass, and on the right for the set, 2 mass.
Antra Gaile: and the the second panel is the female range of the structure of the bottom one was just a bit soon thin, fascinating mark.
Antra Gaile: So this is something efficiency, or this ratio, which is above 99.
Antra Gaile: This is
Antra Gaile: here is the same ratio to other variable loss that previously shown for the other ratio. Again.
Antra Gaile: we don't surpass the 99%, so
Antra Gaile: I cannot perhaps include
Antra Gaile: initially the message, anybody can ask you, okay.
Antra Gaile: very last slide, quick conclusion. Having looked into this
Antra Gaile: for us, this is roughly 4.2 20%. How about the other ratio? 99%. And
Antra Gaile: I have run
Antra Gaile: going through Covid as, thank you very much. Andra.
Giacomo Ortona: Maybe I have one question. So if I go to the slide, I think 5 or 6 where we show the where you show the yeah like
Giacomo Ortona: this, and maybe next one. So for one of these variables.
Giacomo Ortona: So for some of these variables, like, for example, also Z. One mass, but also Z. 2 mass, and so on.
Giacomo Ortona: It looks to me that the agreement in the ratio is worse in the Cms case than what was shown from Atlas.
Giacomo Ortona: I'm not 100% sure. This is actually the case. Or if this is just some blotting a factor.
Antra Gaile: there is a slight plotting effect the
Giacomo Ortona: like. The one of the Z. The the 2 Z masses. So is it one mass, is it 2 months?
Giacomo Ortona: So, for example, for the Zoom mass above 45 40, you can see that the different model style to diverge. Of course we are plotting different things, so we are not plotting the Ft operators. But
Giacomo Ortona: in that case, since that there is an effect of the different models. why did not last the fax team the much smaller. So
Giacomo Ortona: is is maybe just a different scale or something, or
Antra Gaile: there is a bit different scale for us. We are a bit more resuming than the Fisa plots, but Hound probably can comment more on what's exactly the scale that he used.
Michael Duehrssen: Also I see Andre and Mikhail both with a hands rate, my Mikhail, if your is an answer to my questions. Maybe you can go. You can go first. Yeah, at least partial answer. I mean, I'm not sure that the scale of the plot is really the main issue, I mean for sure.
Michael Duehrssen: Also in Atlas case, right? We have seen some differences to the Bsm samples, and it could just be that the Cms Bsm sample choices are more extreme than the Atlas. One
Michael Duehrssen: I think, under we have. We have not discussed which samples we have what the sample definition says. There could just be an artifact of using more extreme samples, and the second point, I think, is the utter simple selection was detuned to the utlasric selection.
Michael Duehrssen: While this Andro is basically still using something that has some changes to the to make it more Cms similar. But some cuts are still more utterly motivated. So it could just be that there is a mismatch
Michael Duehrssen: between Rico and Fiducial. And we are seeing that mismatch between Rico and Fiducial.
Michael Duehrssen: Okay. So this would point to the fact that there is still some work to put the 2 experiment on. I think there is still work is we have to discuss further how to uniform the cut. I've changed the cuts, and then, of course, once we change the cuts
Michael Duehrssen: it is heavily to be assumed that the others agreement will deteriorate where the Cms agreement will hopefully improve.
Michael Duehrssen: We'll have to find a compromise. But I mean, on the other hand, if you look at these plots, even with the current cuts. Right? I mean. it's still much, much better than the current estics, as measurement will be just, inclusive.
Michael Duehrssen: right. This might not be perfect. But yeah, this is already a mild improvement.
Giacomo Ortona: Yep, thank you. A. Okay. I have other questions. But maybe let's go with Andre first.
Andrei Gritsan: Yeah, but the sample subtles with Cms. I would still encourage everybody, including here to do
Andrei Gritsan: particular tensor structure. Particular mass eigenstates, because Gamma star z star. They behave very differently. And if people do the same thing that you can compare, is it 3D.
Andrei Gritsan: The sample which you use, or it's something particle detector
Andrei Gritsan: and also double ratios. But other than that is the usual selection here identical to what was shown for Atlas
Matteo Bonanomi: 100 Year Meeting.
Antra Gaile: Yes, I'm sorry I was struggling to get it back.
Antra Gaile: It should be. With few exceptions, I, in my code, use the Dr. I understood that apple already is using an angle.
Antra Gaile: You could comment, if that is or is not true, otherwise it should be not very close to
Andrei Gritsan: just because the results seem to be different, we should understand. Is it because of the simplified, the the fiducial selection because of the
Andrei Gritsan: detect? The selection?
Andrei Gritsan: Right? Yeah. Both are not perfectly overlapping. Right? So
Matteo Bonanomi: what say the simplified selection that I'm pretty showing in this slide is not actually the same one as outlaws. Is you using for the
Matteo Bonanomi: definition of the social volume. And then we know that at Rico level we are not exactly doing the same event, selection in in between Cms and Atlas. So when you convolute these 2 effects in in? Did you
Matteo Bonanomi: kind of hand up with some differences? One check that is not really comparing apples to apples? Part that Andrew did was to actually use
Matteo Bonanomi: a fiducial selection in the Cms. Case that overlaps with the Rigo selection that we use in Cms. And in that case we see the the efficiency going up as probably around 30%. In that case, instead of the 20% that we see now.
Matteo Bonanomi: So I think that there is room for for improvement. I mean, it doesn't really make sense to compare to Atlas 100%, or rather to expect the same efficiency that Atlas is getting, because we are not
Matteo Bonanomi: looking at the same phase space essentially.
Andrei Gritsan: but the ultimate goal is to define the same usual selection for both experiments. Right?
Giacomo Ortona: Yes, yeah.
Andrei Gritsan: But then you really need to figure out what what makes such a big difference? With the same selection.
Andrei Gritsan: Of course, data you can tune to other selection which makes it better for everybody. But just the puzzle. Why, why, it's so different.
Giacomo Ortona: But I think this is a
Giacomo Ortona: so this is the first time we are allowed to compare this to actually compare this plots. Right? So that that's actually exactly what we wanted to do. And now we indeed, now we have to understand what the difference are and where we can improve.
Andrei Gritsan: But if there is restrictions by experiments not to show in public, you don't have to do it in public, you can do it.
Giacomo Ortona: So the point is that sharing with the other experiment is already public from the point of view. The
Giacomo Ortona: other words, I think.
Giacomo Ortona: but okay, we, I mean, we are working on this right? So
Giacomo Ortona: nothing needs to. The the results from the meeting, I would say is that so we need to tune a bit more the the select definition selection. Yes. And also we need to agree on the on the samples the samples to show so that we can make
Giacomo Ortona: something that is easier to compare.
Michael Duehrssen: I saw that you were muted for a moment. I don't know if you wanted to comment something else I just wanted to say. Of course there's always you can try to do, broke everything out in private and come with a finer solution. But then you don't get.
Michael Duehrssen: let's say, feedback from further brain power in between. or we do something like this where we show work in progress and get in order to get other feedback
Michael Duehrssen: like your suggestions that we do the gamma stars right?
Michael Duehrssen: And I think for these kind of discussions between experiments, there's no perfect approach.
Andrei Gritsan: Well, II didn't suggest to to hide it. I suggested that there is a clear puzzle. This could be resolved right
Andrei Gritsan: now that we know it.
Andrei Gritsan: It's not only changing the feed user selection, that's the
Andrei Gritsan: the Rika selection.
Andrei Gritsan: If you usual selection, the scene. It's a Deaka which may see difference. So it means you want to relax some selection, see? Which one makes a difference.
Michael Duehrssen: Yes. So now, as we did actually this, we try to reoptimize the reconstruction efficiency by really looking at all the observables and seeing, do we have to relax cuts to get above the 99%, and at the same time, where does it not hurt the model independence to relax cuts?
Michael Duehrssen: I think this is somehow an exercise that
Michael Duehrssen: on the Cms side just started.
Michael Duehrssen: And once that is done, I think we have to compare notes and see, okay, where can we sort of compromise best?
Michael Duehrssen: And also this figure of 99%.
Michael Duehrssen: This is not written somewhere in gold. Right? I mean, it's something you want to have it high. But whether it's 99, 98.5, or it's 99.5. I mean
Michael Duehrssen: it somehow. You can call it this the remaining to warm as the unfolding efficiency. Somebody would need to add. if he does a Bsm interpretation?
Giacomo Ortona: Okay, I have another one question and one comment. So the question is also well, I would report to the questions we made by Andre in the last last slide.
Giacomo Ortona: Yep. So no. Sorry in the in the conclusions. Let's say.
Giacomo Ortona: yeah, yes, sir.
Giacomo Ortona: So this is questions that is basically hanging over the discussion. But of course, it's something that is nice to report
Giacomo Ortona: is the S is. So
Giacomo Ortona: what is the plan here is to use Sdx indicate to combine with the production one as an alternative measure, as a.
Giacomo Ortona: and both both production and decay at the same time. So this is the the goal of the measurement should also be made
Giacomo Ortona: a bit clear. And Yup, I will. Now let sorry, just basically because I don't know. There is a comment from Ken on Zoom he's leaving, so I will just report it. And he's asking if any of the speakers would be
Giacomo Ortona: happy if we also make a presentation about this. During the Lxcigs work, Alex. Working group meeting in mid November. I think we can maybe have a one speaker from Cms in that process in the agenda, and then we can coordinate about slides, and so on, is 2 months from now.
Giacomo Ortona: so
Giacomo Ortona: if if you are really against, say it now, please, because we need to finalize the finalize the agenda with the cheeks. Wj. Conveners.
Giacomo Ortona: But I think it would be nice to have it. I'm sorry we kind of interrupted you, please.
Michael Duehrssen: I mean is that try to. I can. I can give you my personal opinion. Right? Let's assume for the hix to Z case that we really reach that goal that we have a
Michael Duehrssen: if you do a selection that is highly efficient
Michael Duehrssen: and give model independence. If that's the case. I would say in all s-tex edge measurements, we basically change what we call Hsu Z, instead of saying H to Z
Michael Duehrssen: is basically the position X to the Z case. Quote, let's see
Michael Duehrssen: adapted to the prophecy for F for Lepton decay, branching ratio, or whatever experiments use. You would basically say, we redefine for lept or Z to be this fiducial volume.
Michael Duehrssen: and then, of course, measured cross-section in Z would go down
Michael Duehrssen: by some amount, because the acceptance on the on the theory side is smaller.
Michael Duehrssen: But you would get the advantage from it that your measurement is more easily re-interpreted in other models.
Michael Duehrssen: So the combination would actually be that
Michael Duehrssen: you you change what you call Z, and later on, hopefully, we would do the same for WW. And you change what you call WW. It would not be all WW. Events, it would be only these WWW. Events in a fiducial volume. That roughly experiment, let's say, roughly, corresponds
Michael Duehrssen: to the experimental phase space.
Michael Duehrssen: And this would be, let's say, the first stage that we try to make our current s. 6 s. Measurements more model independent by reducing the decay, mode, acceptance, effect.
Michael Duehrssen: and then a second stage would be the stage one. That we actually add observables from the decay. M. 3, 4 would be a prime example
Michael Duehrssen: that we not only report on production bins, but also on the decay bins.
Michael Duehrssen: and these would be used by theory people for their model interpretation the same way. They use it now for the production bins.
Giacomo Ortona: but just to sorry to make it clear. So basically, what you're saying is that
Giacomo Ortona: it? Let me.
Giacomo Ortona: So let's let's assume St. Access measurement from Cms at Runtry.
Giacomo Ortona: That's that's a paper and decide. We will have
Giacomo Ortona: one result with the St. Access in production and another one with the St. Access indic one, or it would be.
Michael Duehrssen: let's say, for stage 0 would be the easiest. It would be just one result.
Michael Duehrssen: But your cross section, we quote, would not be gluon fusion, 0 jet times branching ratio Hicks to Z. It would be gluon fusion, 0 jet times
Michael Duehrssen: the branching ratio into the fiducial region that we define here.
Michael Duehrssen: Okay? Because inclusive. Z
Michael Duehrssen: is sort of A is a I don't know is an artifact right? It doesn't exist.
Giacomo Ortona: But then sorry.
Giacomo Ortona: then wouldn't they accept an effect? So you'd still have the acceptance effect of this, the access in production right
Giacomo Ortona: as will come back. This would not. This would net you not neither add nor remove.
Michael Duehrssen: These ones are basically the the acceptance effect next in production, which sort of try to address by doing finer. Pt. Binning
Michael Duehrssen: enter Binning in some kind of jet veto, let's say HJPT. Or whatever right
Michael Duehrssen: we adding, when we see large acceptance effects in the production mode. We usually add a bin subpoena success.
Giacomo Ortona: Okay? I think I understand.
Giacomo Ortona: Mattel. I saw that there was a hand there is a where there wasn't dry first, then, Mateo.
Andrei Gritsan: if it's me. Just one comment here. So potential danger with this approach is that if in the future
Andrei Gritsan: the Atlas of Cemus wants to improve the measurement, I would say, go low in the dialect, invariant mass.
Andrei Gritsan: just because of improvement in our reconstruction or background separation or something. then these doesn't talk anymore. So we set it in stone. What fiducial volume is. But then we can change the analysis.
Michael Duehrssen: Let's see, we. We are always free to add a new volume for a lower. That say, Zet Gamasta, whatever you want to call it, that captures these events right.
Michael Duehrssen: But but you said the whole simplified Temple Cross section now will be defined in this for Lepton volume. It will be these, but, as I mean we are, we are always free to add bins for other events. Right? I mean, we will have a bin
Michael Duehrssen: or the Gamma Star Gammas Gamastaffi dual event selection at some point which will be a different selection.
Andrei Gritsan: I thought we were talking about the production simplified him by cross section. Right?
Michael Duehrssen: No. The whole talk is only about the decay. Simplified template cross section.
Michael Duehrssen: We're not talking about any production here.
Andrei Gritsan: but if we do simplify the Empire section in the future for production, this decay volume would be there right? Or it's not.
Michael Duehrssen: If you have glue, infusion, right?
Michael Duehrssen: You have Zw. WW. Tale tau decase. and in within what you currently call the Z. There would be this phase space we have now.
Michael Duehrssen: But if you take, let's say the Gamma Star product decay modes of
Michael Duehrssen: I'll fix
Michael Duehrssen: also there would be decays that live at much lower invariant masses. and it would likely be very sensible for us to also define a fiducial regions for these events
Andrei Gritsan: I'm still confused. So the the the results which adolescents must publish simplify timel Cross section. There are beans for production.
Andrei Gritsan: jet activity, all of that. So in that analysis. Are we going to apply the 4 Lapton fiducial volume selection.
Michael Duehrssen: I would say as a first stage, yes.
Andrei Gritsan: okay. But that's what I was saying. So if you do that analysis when we set in stone, what Followton means, and there is no room to increase it.
Michael Duehrssen: As I said, I mean, there are 2 ways to increase it. You can define a second bin.
Michael Duehrssen: You don't call it 4, Lepton, you don't call it for Lepton Star or Gamma Gamma Star, whatever.
Michael Duehrssen: and then you have a second. You measure the second bin in the decay side
Michael Duehrssen: the same way as we do in the moment. Right? We measure Higgs to Z. And we measure Hicks to Gamma Star, Gamma Star. Independent measurements, none overlapping in the weaker side.
Michael Duehrssen: We can define the non-overlapping on the fiduciary side.
Andrei Gritsan: But it's not just one beam. There are
Michael Duehrssen: 2030 different beans for production cuts. Right? That's that's the point. Why we do it. Florence, invariant. If its law is invariant. It's valid for every single production. Bin.
Andrei Gritsan: Okay, we keep talking about different things. I'm saying that we we do simplify them plus section 20 beans. and then we add low mass.
Michael Duehrssen: Gamma star region, and then do another 20 bins. So instead of 20 bins, that's the that's the whole point of Lawrence invariant. If it's Lawrence invariant, it's 20 bins. If you add low mass, it's 21 bins.
Michael Duehrssen: because it's the same low mass with exactly the same acceptance with all 20 bins.
Michael Duehrssen: Right? If you think of it, Hicks, let's say that what you currently call Hicks disease. right is, let's say.
Michael Duehrssen: 80% of these events would go in the current fiduciary volume. Then another 10%.
Michael Duehrssen: Would go into a low mass region that you might call Hix to Z. Gama star.
Michael Duehrssen: right? This ratio between 80% going, the the four-lapto fiduciary region and the 10% going into Z Gamastat fiduciary is exactly the same for every single production or and every single production bin.
Michael Duehrssen: it's always the same. So if you measure these 2 numbers, it's just 2 numbers. It's not 2 numbers for each production. Bin.
Andrei Gritsan: II think you're now trying to describe how knowledge would be done in the next stage. I don't know what stage it is. Firstly, you find volume, and then you start doing beans in decay while you keep the same beans in production. I think that's what you're talking about. Right.
Michael Duehrssen: I let's say I think the thing is the needs. This stage one where you define bins need de the decay right.
Michael Duehrssen: whether you, whatever you call them, whether you call them Binson decay, or whether you start calling them. Now, Z. Gamasta is a nomenclature issue. As long as I see 4 leptons in there. It's up to us whether we call them a different decay mode.
Michael Duehrssen: or whether they call them a bin in the fiducias in a different selection.
Michael Duehrssen: The only they have in common. They have. They have 4 leptons. and we want to measure them.
Michael Duehrssen: whether we call it the subplane of a global fiduciary selection or a new selection for a different
Michael Duehrssen: decay. Mode is up to us.
Matteo Bonanomi: But sorry, Michael, because I think I've the same the same. So basically, what you're saying is, we do this definition, and we
Matteo Bonanomi: PIN downward
Matteo Bonanomi: 6 to the Z means for us in the context of STXS. But then the measurement we report.
Matteo Bonanomi: are the current.
Matteo Bonanomi: simplify template cross-section measurements that differentiate different production modes. But instead of using all the events that an analysis would select.
Matteo Bonanomi: we would be using the events selected by the Sdx SDK, definition. Is this the proposal here? Because I'm a bit confused about this, otherwise I don't understand what we would be measuring.
Michael Duehrssen: Yeah, I think so. I mean, we are still under the assumption that institutional selection is
Michael Duehrssen: captures all Eureka events all up to a percent level.
Michael Duehrssen: Right? So you use. Yes, you measure only in your fiducial volume. But your fiducial volume should contain all your record events.
Michael Duehrssen: If later on you change your Rico, so that the retail is much bigger than the fiducial volume. Then we have 2 options. Either we change the fiducial volume.
Michael Duehrssen: or we add a second fiducial volume that contains the new events that you just managed to add.
Andrei Gritsan: Volume would just be one more. The only extra information you don't need to recompute it for each production. Bin.
Michael Duehrssen: No only need the the ratio of
Giacomo Ortona: the original fiducial board to the original fiducial volume, let's say, because then, in any production being that I show would be the same. Yes, so you are not going to do M. Times, M production.
Michael Duehrssen: But that's going to be additive. Exactly. That's that. I mean, that's was actually the starting right many, many years ago that if you do it, Lawrence and Rand, it's additive.
Michael Duehrssen: and it's possible
Michael Duehrssen: right. It's as many bins as you do in the decays, they will just add. And you have basically the full statistics of the events available
Michael Duehrssen: to discriminate between the decay bits.
Matteo Bonanomi: So we still combine, though
Michael Duehrssen: you still combine. Because now we
Matteo Bonanomi: sorry. Yeah.
Michael Duehrssen: if let's assume you have 2, you observe 200 takes to the Z events right? These 200 events are spread over the 30 production bins.
Michael Duehrssen: but you still have, because the decay in the production factorizes you still have exactly the same 200 bins to measure your decay. Bins.
Matteo Bonanomi: No, on the Gary, I'm fine. But then, now, what we can do is is to measure sdx
Matteo Bonanomi: across different production mechanisms sorry across different channels. Every every analysis, every subgroup set Ww. Gamma Gamma do their measurement. We rely on the fact that St. Accessing production is defined only by a
Michael Duehrssen: absolute value of heat, a lower than 2.5 cut, and the beans are common, and therefore we can combine, no matter what's the selection of the efficiency. There's a cabin that you that's really important. We combine by adding one measurement parameter, the ratio between Z and Ww. The ratio between Gamma. So we would replace that ratio by
Michael Duehrssen: exactly the same combination. It's just
Michael Duehrssen: you redefine. What is zw, Toual definition. So that it's less model dependent.
Matteo Bonanomi: Okay, yeah. So you see, instead of being the branching ratios basically is the fraction of fiducial events per indicate ratio. Yeah. But factorizing the fiduciary, it's it's a let's say
Michael Duehrssen: it's a less human ratio readable of branching ratio, but a more physically defined one, because
Michael Duehrssen: the branching ratio. Higgs. Disease simply doesn't exist.
Michael Duehrssen: You can define a branch, Eurasia Higgsophore, Lepton within certain fiduciary regions. That's extremely well defined.
Michael Duehrssen: All your tools. Can calculate it. Pixel Z.
Michael Duehrssen: Is actually something you can't easily define. You can say I call Hixie now the following things.
Michael Duehrssen: but in itself hexes easy is not defined
Michael Duehrssen: right, we're trying actually to to put this on a solid footing
Michael Duehrssen: by defining, what are our final states?
Matteo Bonanomi: Okay, I understand. And and basically just sorry to continue on this, then, for the same logic, it would be the same thing. If you want to do eft interpretations of these measurements and on basically, we still derive as we're doing now, the parametrization of each sdx, a function of the wisdom coefficients. So basically, we parameterize, is is one plus a
Matteo Bonanomi: with some proficient plus b squared value of the recent proficient, with the advantage that now, in doing this would not have the problem anymore of acceptance effects, because we have designed the decay channels in such a way that the effect that acceptance effects are removed.
Michael Duehrssen: Okay, okay, I see
Matteo Bonanomi: upcoming. Wg, meeting.
Andrei Gritsan: One thing was always clear if you made the card dialect on mass greater than 10 or 12 GV. That would
Andrei Gritsan: make enormous difference in the partition of simplified chemical Cross section, that's no question. So some Lawrence and a variant cant like that Epton, Mass. Was needed, no matter what.
Andrei Gritsan: I think you're trying to go much further
Andrei Gritsan: in this and say that there is still 90%. 99%. Efficiency which we still have to see from Cms. But what I understood the ultimate goal beyond just fiducial selection, which would
Andrei Gritsan: simplifying deprecation of as the access that would have you would want to introduce beans in the key. Right?
Michael Duehrssen: So that's the alternative. Before we can go bins and decay, we have to first do the footwork and actually define what we're using. Right? We have to go first. Define. If you do show volume before we can send them. We do bins and decay.
Andrei Gritsan: But what what is interesting? So the just the usual volume cut, no matter what it is dialect, an American mass that that was clear. I don't know 10 years ago that we needed to do something like that to to have
Andrei Gritsan: no acceptance. Well, reduce acceptance. How far we can go is separate thing.
Andrei Gritsan: The interesting question is.
Andrei Gritsan: what's the next step for beans indicate.
Michael Duehrssen: and I guess you're saying it's not the time to discuss it. I mean, I would say obvious ones would be, as you say, M. 3, 4.
Michael Duehrssen: Let's say you do 3, 4 bins, and M. 3, 4. Because almost all observables that you can define M. 3, 4 in. In Z.
Michael Duehrssen: Have that as one of the highest ranks, observables depending whether I mean whether cp. Opt or some eft, whatever. Almost everything changes. M. 3, 4, but need to clarify.
Andrei Gritsan: III agree with you now is not the time to discuss exactly what the beam should be. My question is, how conceptually what would get going. Let's say we defined M. 3, 4, or M. 2 in Cms language. There are some beans there.
Andrei Gritsan: It's on the point. Once we define the beans, how it goes into the measurement.
Giacomo Ortona: So basically from my understanding, can I answer so that I see that if I if I understood.
Giacomo Ortona: then, Mihail, you can correct me? So
Giacomo Ortona: you measure, let's say, the stage 0. That is the number of basically the number of the
Giacomo Ortona: what to define. He existed. Events in the final state. Then you have your 4 or 5 beings in, let's say, and basically all of these you can represent by a number. So the ratio of the. So the fractional events you have in that been over the total.
Giacomo Ortona: and that would be the same for each of the production beams that you're measuring. So you have. You will have 20 production beans. and for each of these beams you have, the information of the
Giacomo Ortona: fractional events that will follow in 2 and 3, 4 in that for that for each of n, 3, 4 beams.
Giacomo Ortona: So you would have 2020 production, plus as many beans in entry for that you defined.
Michael Duehrssen: Is it correct? Yes, essentially, I mean, I think, how exactly you want to define is whether you would do something like let's say, M. 3, 4, smaller than 20
Michael Duehrssen: ratio to total in fiducial as a as, as, let's say, observable vim, or something else. I think we still have to work out what would be the the best definition.
Michael Duehrssen: But if you have, let's say 5 pins and entries before
Michael Duehrssen: then, you would add
Michael Duehrssen: 4 extra observables to the standard, 6 to the Z branching ratio that you already have
Michael Duehrssen: right instead of just an inclusive, you have somehow 4 extra numbers that you measure from all X to Z. Events, regardless of their production mode.
Michael Duehrssen: How we exactly represent them as ratios fractions II don't know directly sums. II think this, we still have to work out what works best.
Andrei Gritsan: And then a published paper would have regular simplified chemical cross section.
Andrei Gritsan: plus 4 numbers fractions wherever is defined.
Andrei Gritsan: and there will be some covariance matrix between those
Michael Duehrssen: f's and whatever they are, they being, sir, right? Exactly. It would be they would come out of one fit of everything right, you would not measure them separately, it would be one fit. and you would have some covariance. Hopefully, the covariance should be small to the production mode, because they should be really uncorrelated.
Michael Duehrssen: But it will depend, of course, on event migrations, whatever what you see.
Michael Duehrssen: and of course we will have to
Michael Duehrssen: to define what is the observable same way as in the production board. People argue, do we want to do Delta phi, J. Do we rather want to do more. MJJ. Do we want to do PTJ. For VBF.
Michael Duehrssen: We will have to argue. Which which observables do we want to define?
Michael Duehrssen: And how many can we afford to define?
Michael Duehrssen: I would say to me, M. 3, 4 would be obvious. Once you have defined MC. 4 bins. Basically the Q square of your 4 Lepton system is completely defined.
Michael Duehrssen: and afterwards
Michael Duehrssen: you could even do continuous eft parameters. For the rest, because then the Q squared is fixed and dft is really valid.
So
Michael Duehrssen: to me, M. 3, 4 would be the most important, because it's I mean, obviously very, very sensitive, and also it fixes the Q square
Michael Duehrssen: of the whole, the case system, and afterwards you can do a full expansion whatever you want to do.
Giacomo Ortona: Thank you. Are there any more questions? I think this point is now quite clear.
Giacomo Ortona: Okay, if there are no more questions I assume that the 2 working team from Cms and Atlas will.
Giacomo Ortona: we'll keep comparing the results and make the necessary fine-tuning.
Giacomo Ortona: And
Giacomo Ortona: well, I think the next Update is going to be actually in mid November at the Reach 6 working group workshop. Since this seems more or less in any case, is not too far
Giacomo Ortona: too far away.
Giacomo Ortona: and so let me thank everybody to have been here. I hope also to see you tomorrow for the meeting with the Wg. 3 on Cpb and Cp regulation.
Giacomo Ortona: If there are any questions, any suggestion or so on
Giacomo Ortona: well, you can either ask the speakers of today or or the Wg. 2
Giacomo Ortona: and I will. We will post. Only Nico page. Some minutes, and and the recording of today as well, so that for anybody that to see a summary of what we discussed today.
Giacomo Ortona: And again. Thank you very much.
Matteo Bonanomi: Thank you bye, bye.
Paolo Francavilla: So
Marco Menen: bye-bye.