Jonathan Samuel Wilson: Good morning!
Brent Yates: Morning, John.
Jonathan Samuel Wilson: Or, I suppose, afternoon to Chicamo.
Giacomo Boldrini: High.
Jonathan Samuel Wilson: Okay, we've come to the start of the hour, but we'll give it a couple of minutes, probably to allow more people to trickle in
Jonathan Samuel Wilson: hopefully. We can get pretty good attendance today, but we'll see.
Jonathan Samuel Wilson: Nick. We don't have any news or announcement slides. So if you wanted to go ahead and start your screen share. That'd be fine. But don't feel obligated.
Jonathan Samuel Wilson: I can see your slides. They look good.
Jonathan Samuel Wilson: I think we've got a decent number of people here now.
Jonathan Samuel Wilson: So let's go ahead and get started. So today we have a a summary of the recent Lpcft workshop at Notre Dame. Nick Smith, will be giving that summary and I will remind everyone that this is an open meeting, not a Cms internal meeting this week. So please make sure that we keep everything
Jonathan Samuel Wilson: that should be Cms internal out of this meeting today.
Jonathan Samuel Wilson: All right, whenever you're ready, Nick, please go ahead.
WH11SW- Sunset: Okay. Can you hear me?
Jonathan Samuel Wilson: I hear you just fine. Thank you.
WH11SW- Sunset: Okay?
WH11SW- Sunset: yeah, I guess I can get started. Then.
WH11SW- Sunset: so yeah, this is a summary of the workshop that was now
WH11SW- Sunset: a couple of weeks ago.
WH11SW- Sunset: kind of in terms of how it was organized. I thought I'd briefly kind of go through.
WH11SW- Sunset: You know how we planned it out and and and the goals of it. So the first day was a tutorial. There was a nice introduction to eft. Thanks to Ben Mozi and Adam Martin.
WH11SW- Sunset: 2 theorists that work in in that area.
WH11SW- Sunset: And then after that, we kind of went into this
WH11SW- Sunset: exercise where people would start with a mad graph card using Smith, SIM Ufo model go through Nanogen to Instagram to combine just to see a a pipeline, you know, a sketch of a pipeline for a potential analysis.
WH11SW- Sunset: Just to get people familiar with the different steps and the different tooling
WH11SW- Sunset: and then taking off of that tutorial. We had a hackathon Tuesday and Wednesday, where people worked in small groups on generating a sample or any other project that they they felt was was worth the time
WH11SW- Sunset: collaboration time. I thought this was actually a very effective.
WH11SW- Sunset: We saw a lot of a lot of people interacting with each other. And that was that was really nice. On Wednesday. Actually, we got a bonus tutorial on effective field theories and Smith from Michael Peskin.
WH11SW- Sunset: And that was that was really excellent. I have to say just.
WH11SW- Sunset: you know.
WH11SW- Sunset: as we were leaving the room, I had never seen so many people immediately go to whiteboards and start drawing fireman diagrams before, like people were very like excited about this. After that, after that tutorial, they felt like they had the tools they needed to ask questions.
WH11SW- Sunset: So that's good
WH11SW- Sunset: then the last 2 days, you know, was a workshop where we had semantic sessions with extended discussion time, and then, and then several invited speakers.
WH11SW- Sunset: All the sessions were recorded and are available on the agenda now already. So feel free to go watch those. If you if you're interested
WH11SW- Sunset: a bit about the participant statistics, we had 50 registrations and we also asked during registration, you know, what kinds of session. Would you be interested in? So people get to choose 3 of the 5, so that we would have at least some
WH11SW- Sunset: some people that didn't select all. And so you can see, the popularity varies by the topic. And what these topics mean I'll go into in the next slide.
WH11SW- Sunset: But yeah, you can see, maybe a waning interest in unfolding which you'll maybe see
WH11SW- Sunset: aspects of later on in the in the talk
WH11SW- Sunset: so the session themes. We start with how far beyond linear, which is basically focusing on issues of truncation and validity with an interpretation of results with Ni towards practicality. So this is things like, you know, dimension 6 squared dimension, 8, etc.
WH11SW- Sunset: multiple insertions.
WH11SW- Sunset: Then we had building a sample library which is how to best generate simulation samples for use and data analysis, logistics. How to bring in divers arrayed measurements into a cohesive whole
WH11SW- Sunset: specific consideration for unfolded results, which is
WH11SW- Sunset: basically how to design fiducial measurements for later use and Efi interpretations, and then the benefits and limitations of that.
WH11SW- Sunset: And then the last theme was specific considerations for reconstruction level results, which is how best to design analyses directly targeting inference. A Vfd parameters. So this is.
WH11SW- Sunset: you know, let's say, direct reconstruction level binning or simulation based inference techniques. If you're into Ml.
WH11SW- Sunset: it's interesting to contrast these themes with the Lhcft working group areas. Because, as we were putting this program together. We never thought to compare our themes to the areas. But if you do it after the fact, you can see some matching, for example, how far beyond linear really lies in the formalism
WH11SW- Sunset: sample library kind of blends, prediction and tools. And, and, you know, fits and systematics.
WH11SW- Sunset: Logistics, obviously, fits and then unfolded and reconstruction level really gets into
WH11SW- Sunset: kind of experimental measurements and observables. So you can see we we touch 4 of the of the 4 working group areas. And one of the talks actually, also kind of gets into. Actually, 2 of the talks get into looking at things from the perspective of a UV model.
WH11SW- Sunset: So that was nice.
WH11SW- Sunset: As for the summary, we are in the process of drafting a summary document the session shares become the section editors for this. All the speakers have already contributed a one paragraph summary to talk, which is, I'm really happy about. We're kind of calling it a proceedings light
WH11SW- Sunset: and then editors will add to it, contextualize the summaries of discussion.
WH11SW- Sunset: And so in the next slides. Basically, I will summarize these summaries. And clearly, this is a gross injustice to all speakers, even if I do it correctly. And you can make amends for my transgressions by watching the recordings. I was there. So
WH11SW- Sunset: it's up to you.
WH11SW- Sunset: Okay. So starting off Dorje had this talk about.
WH11SW- Sunset: you know, freedom to choose what is small and matching UV to heft.
WH11SW- Sunset: There's many, you know. If you have a UV model, you have several different parameters, choosing which one is small, can lead to different expansions, and usually one of the choices leads to restriction of the operator space to smft operators, which is good cause we're all kind of going for smept. Unfortunately, that choice is not always the fastest converging. So I picked one plot where you can see
WH11SW- Sunset: basically that the the yellow power counting, which is the Smith power counting doesn't perform quite as well as an alternative power counting in blue at
WH11SW- Sunset: at quadratic order. But you can say they're close. So maybe it's we're not losing too much. Neither of them are great compared to the full UV model in terms of the dependence on the
WH11SW- Sunset: the model parameter. Which is this sign of this angle?
WH11SW- Sunset: And
WH11SW- Sunset: you add a scalar field. If you want more information, of course. Go watch his talk.
WH11SW- Sunset: Adam Martin, was really trying to focus on the fact that the Lambda negative forth terms are not as scary. If we focus on low vertex account diagrams. Basically, Geosmith proposed proposes to reorganize Dimension 6 and Dimension 8 operators to allow for a more pleasant number of operators to consider and fits. For example, if you consider just propagator corrections at Dimension 6 or 14, and
WH11SW- Sunset: for 3 particle vertices. You have 20, and then it shows how, if you go to Dimension 8, these numbers don't increase dramatically. They go to 19 and 47. But of course, higher multiplicity vertices explode. So that's a motivation for focusing on these.
WH11SW- Sunset: you know, say, leading order diagrams, things that you could actually pick out quite easily. It was interesting to note in that talk in the discussion session the
WH11SW- Sunset: his response with respect to Gsm. Next leading order in Alpha S. Because then that destroys it destroys the relationship and makes us all a bit more thorny.
WH11SW- Sunset: So we have to be a little bit careful at Lac about adopting it. Yeah.
WH11SW- Sunset: anyway. So William Shepherd also provided this.
WH11SW- Sunset: let's say, prescription for how to use a dimension 6 squared is a theory, uncertainty
WH11SW- Sunset: and ideas that this would provide some output where our result would say, model is either unconstrained or potentially constrained, ie. The exclusion region.
WH11SW- Sunset: You know, would rule out this model if you ignored this dimension. 6 squared theory, uncertainty.
WH11SW- Sunset: And then you would need model specific searches in the same data. To
WH11SW- Sunset: fully determine if you're constraining it. And then finally, with this theory, uncertainty allowed. If you're still in Exclusion region, then you can maybe say that this model is definitely constrained. So he like to make the analogy of like red light yellow light for for UV models. And then there's the prescription that he proposed, which I think needs further discussion to to actually implement. But I think it's a good action item for us to understand how to implement this.
WH11SW- Sunset: Okay? Going on to reconstruction level results. Sergio made a point that
WH11SW- Sunset: These are generally going to be more accurate and sensitive than unfolding at a cost right? Because you have a fixed model so changes must be at detector level
WH11SW- Sunset: and the big, the big motivation, you know. One example here is, you may have
WH11SW- Sunset: developed a a search for eft coefficients with top lefton operators, and then later, you decide you care about the lighter quarks as well. And so you have to care about quarks coming. Left ons coming up on initial state, and how to fold that in is is challenging. There is a possible technical solution where you use some combination of post generation re-weighting a public signal sample and a public likelihood.
WH11SW- Sunset: In each of these terms. You'll see these these Co. Come up often in in the talks, so you'll you'll see these names again.
WH11SW- Sunset: I would say. Dorville's main takeaway for us is that we should really embrace spin correlation information, including decays. He pointed out that electronic decay of a top quark. The left hand be is an excellent polar emitter. It provides basically a one X scaling of this cosine of this data in terms of the cross section, dependence
WH11SW- Sunset: and hydronic is less. But with enough work you can get to a number that is not too far from one. So point 6 4 with some fancy angular information.
WH11SW- Sunset: And so I think this is, you know.
WH11SW- Sunset: a good direction for us to not neglect hydronic decays of of tops, or even other
WH11SW- Sunset: like vector bosons.
WH11SW- Sunset: because they can carry angular information that is useful for disentangling
WH11SW- Sunset: the tensor structure vertices. And we shouldn't. And you know, we'll have more hedonicays at high momentum. So that's another reason to go for it.
WH11SW- Sunset: Andre, focused on explaining sort of the quality hierarchy of observables, if you like, where sort of standard model observables that are just meant to suppress background or the lowest tier eft. Sensitive observables, like angular information or transverse momenta, are more useful in eft contacts. Obviously, optimal observables, either via matrix element or machine learning are optimal for the appropriate definition. And then, lastly, you can imagine a full
WH11SW- Sunset: event information, and obviously the trade off as you go to higher and higher quality, is the modeling complexity which you discussed at length. And there was kind of this question, you know, should we be pursuing matrix element or machine learning methods? For designing optimal observables. And his take was that
WH11SW- Sunset: ml, is useful when you have, you know, part time, shower effects, missing particles, comp complicated combinatorics, and when the matrix element is not easily calculable.
WH11SW- Sunset: and when those are not a problem. Then matrix element is a lot cleaner and simpler, and you should embrace it was his main point.
WH11SW- Sunset: Harrison, prosper was encouraging us to look at how to regress the Cdf for the test statistic to construct content sets so for background. Here, you know, traditional simulation based inference techniques focusing on focuses on estimating either the sort of the probability of the data given some model parameter, or the probability ratio which then we usually
WH11SW- Sunset: plug in the data and interpret as a likelihood or a likelihood ratio of the of the model parameters data.
WH11SW- Sunset: And so you would estimate this via some machine learning regression technique. And that's what you see in in tools like mad minor.
WH11SW- Sunset: Now, the question is what you do once you have this likelihood ratios, test statistic, which you know, this is the most common test statistic we use.
WH11SW- Sunset: You use that statistic to do hypothesis tests. So this slide and set here is
WH11SW- Sunset: let's say, textbook conference region explanation?
WH11SW- Sunset: And the point is that at some point you have to compute a cumulative distribution function of this test statistic and find where the observed value lies in it.
WH11SW- Sunset: Well, the question is, can you use machine learning techniques like conditional quantile regression, to estimate that you know the distribution
WH11SW- Sunset: with lower needs on your simulator. And the answer seems to be, yes.
WH11SW- Sunset: So if you're interested in that, you can look at his talk
WH11SW- Sunset: okay onto logistics. So Tom, John, provided an excellent overview of how Lep and and Tevitron performed a combinations. I think it's really interesting to think how Lep routinely did this with 4 separate experiments at the same time, with only Fortran callables and auxiliary data files
WH11SW- Sunset: so sort of definitely a back in my day moment. And Tevichron we saw, you know, increasing complexity and the move to C, and more frameworks. But nevertheless, the things that you want to be able to do. The requirements have not changed even since the left days. And so it's it's nice to see that.
WH11SW- Sunset: you know the tools that we're developing now will will meet these requirements and have met the requirements for a long time.
WH11SW- Sunset: Kyle pushed a lot to publish the full statistical model. So this is bringing us back to Sergio's point about how to reinterpret
WH11SW- Sunset: reconstruction of the results.
WH11SW- Sunset: So a a second level. You also recommended that we define an eft model specification exactly how the the surrogate likelihood model that we form depends on the ft. Parameters in a in a more rigid structure, and to use reanalysis, structure.
WH11SW- Sunset: infrastructure. So here, you know, I've just kind of grabbed one example of an effort to publish full statistical models with the Hep statistics serialization standard. And then, as soon as I pasted this in here, I realized I took a screenshot of a slide full of screenshots of slides. So
WH11SW- Sunset: clearly we need to go deeper.
WH11SW- Sunset: Michael, gave us this very nice overview of why die top production at ee machines, and clearly only certain ee machines. Given the top mass. Is a really worthwhile endeavor, because you can disentangle operator effects with both the polarization and energy scan and really get at a lot of a lot of effects and and understanding them.
WH11SW- Sunset: So onto unfolded results. Andrew
WH11SW- Sunset: made a statement to the effective. They are an insurance policy which I think is a nice way of capturing the the philosophy.
WH11SW- Sunset: Differential cross sections may not be optimal eft pros, but they are always reinterpretable in any Bsm scenario, and the machinery is well established. Right? We have.
WH11SW- Sunset: You know. He's developed a Cft to Ops tool where you can take any. You have a model, plug it through a rivet routine and get exactly, you know the eft, the model constraints out of that in a very.
WH11SW- Sunset: a very automated way, module, background, subtraction. So clearly we should continue to publish those results.
WH11SW- Sunset: Jonathan pointed out that Scx is simplified. Template cross sections is a very natural framework for smaft interpretations of Higgs results. It kind of meets in the middle between unfolding and and full reconstruction level.
WH11SW- Sunset: and of course it has all the caveats that you would usually find for unfolding, and he made a particular point to focus on acceptance effects, especially in Higgs. Disease decays because simplified template cross section has nothing to say about decays, and it shows some demonstrations of where the acceptance corrections can dramatically change the coefficient dependence of a of a signal string of been yield.
WH11SW- Sunset: Frank
WH11SW- Sunset: wanted to stress that precision drill. Yan provides a wealth of smift constraints.
WH11SW- Sunset: and he casted it into this traditional angular decomposition, but then extended it to account for thing angular coefficients that are exclusively brought out by dimension a Smith behavior.
WH11SW- Sunset: So you know, we have the traditional decomposition. And then these new bi terms that
WH11SW- Sunset: that represent angular behavior that you would only see. And so this could be a smoking gun for dimension 8 effects. And so we should continue to produce these drag and angular decompositions.
WH11SW- Sunset: Okay, onto building a sample library. So Luca stressed that the Pdf. Is flexible enough to absorb the effects of new physics.
WH11SW- Sunset: There was this demonstration with this toy model, with a very heavy W. Prime that was then matched to Smith coefficients, and then fit in this toy, where
WH11SW- Sunset: the data is that true? Pdf. Convolved with the the true new physics represented here by by eft expansion. And then the theory would be what you would fit. The Pdf to the the data with the Standard Model Cross section you. What you basically see
WH11SW- Sunset: is that
WH11SW- Sunset: the the Pdf shift is completely compensating for the new physics effects. So the statement is that the new physics is concealed in the fit. The Pdf.
WH11SW- Sunset: so
WH11SW- Sunset: his solution for these kinds of problems is is twofold. One is to design more conservative pdos for use with Smith fits that don't try to extrapolate as aggressively, and and have this this ability to to absorb new physics, and also that we need more forward physics data because it can disentangle Pdf and smept effects because they happen at low versus high. Q squared.
WH11SW- Sunset: So Andrew
WH11SW- Sunset: discussed how Monte Carlo rewaiting is A is a very powerful tool and significantly reduces our computing needs for for modeling. Eve Tfx. In full simulation.
WH11SW- Sunset: however, choosing a starting point and validating a statical power is important and and needs careful thought.
WH11SW- Sunset: We definitely need
WH11SW- Sunset: more quantitative prescriptions for this. He demonstrated the qualitative prescriptions that
WH11SW- Sunset: that the their their analysis had had gone through and and showed what kind of things you want to see, like nicely peak weights, and not a broad distribution improved approaches for storing and propagating eft was also a point. He he raised that we need to
WH11SW- Sunset: improve our plumbing and and Cms software and elsewhere.
WH11SW- Sunset: Charlotte pointed out that a common eft parameterization is more efficient and accurate, and we should really pursue this. So this is again
WH11SW- Sunset: a point that that
WH11SW- Sunset: reiterates what Kyle said right? We need to establish conventions for this.
WH11SW- Sunset: because deriving the accurate Sc. Excess parameterization is a significant undertaking at the moment triplicated between Cms. Atlas and and Theoris
WH11SW- Sunset: so if we can define a common format and be done with it, that would that would save everyone some time, and also reduce bugs, and he had this nice hackathon project where they where he was trying. She was trying to automate with automate. This process with Snakemake.
WH11SW- Sunset: another big hit from that talk was the post generation rewinding. So Charlotte has arrived
WH11SW- Sunset: sort of a module to take events at
WH11SW- Sunset: Lh level and compute alternative matrix element weights. And
WH11SW- Sunset: you can do this even at Nanood. And so this was brought up also in Sergio's talk. But
WH11SW- Sunset: sort of the the full workflow was was highlighted here, and that was discussed at length.
WH11SW- Sunset: So that's actually all of the talks we had. I didn't want to go into the discussion, because well, without the context of the talks, the discussion wouldn't have made a ton of sense. But if you want to read about the discuss discussion
WH11SW- Sunset: that we had. You will find it in the note that will be posted on Archive in about a month.
WH11SW- Sunset: and we'll send that around.
WH11SW- Sunset: So we had a good time, and consider joining us next time.
Jonathan Samuel Wilson: All right. Thank you, Nick. That was a very nice summary. Are there questions or comments or discussion.
WH11SW- Sunset: Yeah, maybe we wanna go back to Lindsay's comment. I just wanted to go through the slides. Sorry for butting in there.
WH11SW- Sunset: Yeah. So the the the point here is just that if you start looking at the next leading order in Alpha S, and you consider
WH11SW- Sunset: a 3 point diagram
WH11SW- Sunset: in eft space. Then you'll automatically get
WH11SW- Sunset: standard model diagrams that look like the 4 point diagrams and will interfere with
WH11SW- Sunset: whatever order of, or yeah, your your side of the 4 operators, or something like that. I'm sure you can kick, cook up the dimension. 8 operator. That you can find that fits your final state with an additional jet emission.
WH11SW- Sunset: And suddenly, you have something that you actually really want to pay attention to in your cross section. Yeah. Well, what I was wondering is this implied? We need to move towards more exclusive? You know, jet counts like. So you would do. Let's say.
WH11SW- Sunset: vv plus 0 jets analysis at a high trend that might be a way around it to to preserve that kind of simplicity. Because if you can get away from hard jet, hard radiation. And you're in, you know. Yeah, then you're in the zoom area. Effects are small or constrained by precision. Observables of some sort. Yeah. And so I I I was under the assumption that this that was implicit here, that we would have to make cut some multiplicity, and we don't have any
WH11SW- Sunset: anything we anything extra, let's say in our in our final states.
WH11SW- Sunset: only only what would be produced by the simplest vertices. That's possible. Yeah. But we have, we have to
WH11SW- Sunset: make sure that we consider that when we're engineering these analyses in the future, because people often don't do that.
WH11SW- Sunset: Yeah, I mean, generally it's safer not to right. You don't want to make it, because then you have to worry about the Jpt. etc. And you did systematics. You really don't want to calculate
WH11SW- Sunset: but it seems, or at least for this particular deployment of of eft techniques or of eft measurements.
WH11SW- Sunset: It's something we have to consider to get a con a consistent result out of it. And it's just not been.
WH11SW- Sunset: And I imagine it being especially difficult to do that kind to enforce that kind of requirement for a top and other things with lots of color charge in the final states. Right?
Jonathan Samuel Wilson: I will say that every time I hear Adam talk about this it always seems very sensible and straightforward
Jonathan Samuel Wilson: while he's talking.
Jonathan Samuel Wilson: and then afterwards I go wait! How did I think this was simple? I forgotten my understanding of it.
Jonathan Samuel Wilson: but.
WH11SW- Sunset: Yeah.
WH11SW- Sunset: that goes for a lot of things.
Jonathan Samuel Wilson: Yeah.
Jonathan Samuel Wilson: yeah.
Jonathan Samuel Wilson: I see a raised turn from Septa. Go ahead. Sapa.
Saptaparna Bhattacharya: Just I know I was really thinking where I even should raise my hand. But this is just a basic like a follow up to exactly what was being discussed. So, thinking a bit more about these exclusive jet bins, I was thinking that we at that point we really need to consider, or really just think about what a jet is. Even a generator level quantity or reconstructed. Ak, 4, ak. 8, all of that. And then is it. Akh 8 without overlaps with Ak, 4 things like that.
Saptaparna Bhattacharya: So I think it would be very interesting. But and certainly worth doing. But it also, you know, there are a bunch of questions that arise when you start doing these exclusive you know treatment. But people certainly have been doing this for, say, one of the recent analysis that I can think of is the Z plus jets where they did look into ex exclusive jet bins. Actually, even Www. At 13 TV, does it? So it's certainly possible. It's just.
Saptaparna Bhattacharya: We have to be very careful with the eft analysis, because we tend to mix different kinds of jets, because we are trying to probe the high transverse momentum region.
WH11SW- Sunset: Hmm.
Saptaparna Bhattacharya: So, yeah, just a comment, I suppose.
Jonathan Samuel Wilson: So I'll just make a comment regarding the logistics of combining likelihood, which is that
Jonathan Samuel Wilson: I think that we all all across Cms and Atlas. 2 need to be doing more to
Jonathan Samuel Wilson: at the the planning, the analysis stage. We need to be doing more, to plan for our analysis to be combinable.
WH11SW- Sunset: Yeah, there, there's lots of Co cultural shifts that need to happen in order to get this commonplace absolutely.
Jonathan Samuel Wilson: Right.
Jonathan Samuel Wilson: And and we absolutely need to
Jonathan Samuel Wilson: seriously pursue some of the things that Kyle was talking about about having specifications that are separate from implementation and actually creating and then adhering to those specifications, I think, is is
Jonathan Samuel Wilson: absolutely worth doing.
Jonathan Samuel Wilson: And I don't know how to actually get it done sociologically.
Jonathan Samuel Wilson: you know, where? Where's the the career award for? Not not career award in terms of, like, you know, a prize, but like the the progression of career for somebody who spends their time working on this.
Jonathan Samuel Wilson: That's always a difficult sort of question.
WH11SW- Sunset: It's a directive that I mean, you have to.
WH11SW- Sunset: You have to convince people that it's worth it to adhere to the rules. At the same time that you suggest the rules from somewhere, like the Lec working group on the fts.
WH11SW- Sunset: Yeah, you have to kind of grow from the top and the bottom at the same time. Otherwise
WH11SW- Sunset: the
WH11SW- Sunset: otherwise, the momentum just dies out and therm, and every everyone just thermalizes back to doing their own thing.
WH11SW- Sunset: You kinda you have to figure out a way to meet in the middle. And I I
WH11SW- Sunset: how much of how much of that kind of momentum are we missing? And from the top, so to speak.
Jonathan Samuel Wilson: Yeah.
Jonathan Samuel Wilson: yeah.
WH11SW- Sunset: From like the Lac working groups. Or is there anything we could do with this group to
WH11SW- Sunset: beat people with hammers.
Jonathan Samuel Wilson: Yep.
WH11SW- Sunset: Yeah, I know this group is being absorbed or something like that. But.
Jonathan Samuel Wilson: Something like that. Yeah.
Jonathan Samuel Wilson: yeah, at least the the contacts, the conveners are gradually being merged with the Lhc eft working group contacts.
Jonathan Samuel Wilson: So.
WH11SW- Sunset: Yeah, I mean, in terms of top down structure for this. It was really helpful that the seamless collaboration board approved the statement that we will release all public likelihoods, all of all analysis likelihoods in the future.
WH11SW- Sunset: of course, implementing that that requirement will be
WH11SW- Sunset: a challenging process for everyone. But it does sort of create a mandate for groups like cat stats to to, to develop the necessary tooling. And they have been.
WH11SW- Sunset: So I think that's encouraging, and what I hope is that cats can interface with HS. 3 and and kind of come to
WH11SW- Sunset: come to a good conclusion. But I think the the story is just is just starting there. Now that we have this open likelihood mandate.
Jonathan Samuel Wilson: That's a good point. That is very helpful. Yeah.
Jonathan Samuel Wilson: Jacqueline.
Giacomo Boldrini: Hi, yeah, May, maybe
Giacomo Boldrini: it's more of a question, but
Giacomo Boldrini: follows closely what what you were discussing about this. But
Giacomo Boldrini: in this, in this view. For me it would be very interesting to explore this.
Giacomo Boldrini: Let's say, none of the postmortem re-weighting tools in order to the couple. From
Giacomo Boldrini: from what an analyst has to do in terms of eft and what we can do in terms of the combination right? Because we can analyze eft
Giacomo Boldrini: after the the
Giacomo Boldrini: the analysis is done, and then we can. We can also.
Giacomo Boldrini: let's say, have a larger pool of analysis to combine for the eft right?
Giacomo Boldrini: But I know that I mean, sometimes I mean, this is not a general tool. I mean, sometimes it works, sometimes it doesn't.
Giacomo Boldrini: So I was wondering whether
Giacomo Boldrini: there were some comments and things that can be developed
Giacomo Boldrini: in order to make the re- waiting work in an arbitrary scenario.
WH11SW- Sunset: Yeah. So I think Sergio went into this a bit a bit more. Basically.
WH11SW- Sunset: you know, if you have somewhere stored.
WH11SW- Sunset: let's say, the matrix element, level kinematics
WH11SW- Sunset: of your signal samples.
WH11SW- Sunset: then, in principle that, plus the bin that those those events were assigned to in your into in your final fit
WH11SW- Sunset: is sufficient information to do a fully.
WH11SW- Sunset: It's a fully rigorous
WH11SW- Sunset: re-weighting and and re-analysis later, using a post generation re-weighting
WH11SW- Sunset: to the extent that post-generation rewaing can accurately give you the matrix element ratio. For, say
WH11SW- Sunset: this, this kind of process over this kind of process as a function of the
WH11SW- Sunset: the outgoing kinematics.
WH11SW- Sunset: which is, is a bit non-trivial statement, right? It. It may not be the case that that that closes, but
WH11SW- Sunset: the hope is that it does, and therefore we can like you say.
WH11SW- Sunset: Yeah, have analyses.
WH11SW- Sunset: Reconstruction level, you know. Go through the process without worrying too much about the Ftn. Then, later on.
WH11SW- Sunset: adding that interpretation.
WH11SW- Sunset: But you know that doesn't remove thing issues like
WH11SW- Sunset: event overlaps and how to deal with correlating systematics across analyses that haven't traditionally been combined. Then that's that's still going to be challenging, even even without the eft complexity.
WH11SW- Sunset: But yeah, I think this is a good point, and and maybe we can.
WH11SW- Sunset: Well, I I shouldn't say maybe we can see evidence of this because we have seen evidence of this.
WH11SW- Sunset: jonathan talked about explicitly doing this I I didn't have time to talk about. If you look at his talk.
WH11SW- Sunset: you know, in Scxs we are looking at reconstruct acceptance corrections of existing Higgs
WH11SW- Sunset: measurements and and unfolding any of the effects on acceptance
WH11SW- Sunset: for the the legacy. Higgs combination.
WH11SW- Sunset: so that that tooling is being is actively being deployed in the case of pigs.
WH11SW- Sunset: But to see a wider audience, I think we'll need to
WH11SW- Sunset: spend more time and have more people investigating it.
Giacomo Boldrini: Yes, I agree. I I fully agree.
Giacomo Boldrini: Yeah, I mean, I tried these
Giacomo Boldrini: procedure. But the problem was that basically it assumes that the start. The point is a standard model most of the time, I mean
Giacomo Boldrini: on the central node, or wherever.
WH11SW- Sunset: Right, that.
Giacomo Boldrini: I mean, in some cases it can lead to really, really physical prediction for eft, for complex processes. So
WH11SW- Sunset: Yeah, you you. It's hard to reweight when you have to divide by 0. That's for sure.
Giacomo Boldrini: Yeah.
Giacomo Boldrini: thank, you.
Jonathan Samuel Wilson: Alright any other questions or comments.
Jonathan Samuel Wilson: All right. Well, thank you very much, Nick, for an excellent summary, and I hope to see everybody at the next Lpcif workshop.
WH11SW- Sunset: Me too.
Jonathan Samuel Wilson: And I think that's it for this meeting. So thank you, everybody, and we'll see you
Jonathan Samuel Wilson: next time.
Jonathan Samuel Wilson: Bye, bye.
WH11SW- Sunset: Bye.
Kelci Mohrman: Thanks, bye.
Alessandro Calandri: Thanks, bye.
WH11SW- Sunset: Oh!