Go Beyond Jet-Level Information at Precision Era
CC Attribution 3.0 Germany:
You are free to use, adapt and copy, distribute and transmit the work or content in adapted or unchanged form for any legal purpose as long as the work is attributed to the author in the manner specified by the author or licensor.
Li, Lingfeng
Information deformation and loss in jet clustering are one of the major limitations for precisely measuring hadronic events at future ee colliders. Because of their dominance in data, the measurements of such events are crucial for advancing the precision frontier of Higgs and electroweak physics in the next decades. We show that this difficulty can be well-addressed by synergizing the event-level information into the data analysis, with the techniques of deep neutral network. In relation to this, we introduce a CMB-like observable scheme, where the event-level kinematics is encoded as Fox-Wolfram (FW) moments at leading order and multi-spectra at higher orders. Then we develop a series of jet-level (w/ and w/o the FW moments) and event-level classifiers, and analyze their sensitivity performance comparatively with two-jet and four-jet events. As an application, we analyze measuring Higgs decay width at ee colliders with the data of 5ab^-1 @ 240GeV. The precision obtained is significantly better than the baseline ones presented in documents. We expect this strategy to be applied to many other hadronic-event measurements at future ee colliders, and to open a new angle for evaluating their physics capability.
 Hi, I'm Langston Lee from HKEUSD. I'm very glad I can speak on behalf of my collaborators about Go Beyond Jet Level Information at Precision Era. So as we all know, if we are lucky, so we are moving to a precision frontier in next decades, leading by those high energy electron colliders. And the primary goal of this phase, or well, era is to measure electrical weak and Higgs very precisely, and eventually we are dealing with WZ and, well, I mean, Higgs-related decays. And as you can see right here, most of these decays are dominated by, well, I mean, hydronic modes involving hydrants in the planet state. So which is a must, okay, if we want to know very well these sector, we need to know these hydronic modes and usually that's a bottleneck because we are relying on the definition of jets when measuring these modes and AKA jet clustering. And usually that would not be satisfying when facing with the need of precision. For instance, we can have an E to Z, Z to four jet event. If we project this example event into theta-5 plane, and we can see that on the other half of a plane, hydrants from different Z get clustered into same jet, which means clearly clustering distorts information from truth level. And even when the distortion is not significant, we will have information loss because many dimension of information is well gone after clustering. So in order to compensate the effect, we'd better think about how to put the whole event without loss into the analysis framework. And one effective way is to like treat the event as an image. For instance, to better understand this, we project while cumulative events into the sphere after, well, I mean, several pre-processing steps, but after pre-processing independent of jet prediction, we can see, well, for E to QQ back-to-back event, we can see two patterns go back-to-back, well, two energetic flows, looks like two jets, fine. And for E to ZZ, where one ZZ to two jets, we find the typical angular separation between these two quarks or jets, therefore forming a halo-like structure. So in this way, we can achieve the no-lose of information and the maximum input we can get. And when studying this, we notice the close resemblance between such event level projection and, well, I mean, the all-sky CMB map well-studied in cosmology. So because they are all projections of, like, say, either energy, temperature, or you can say, PT, charge, whatever you want on the detector sphere or the celestial sphere, a spherical image. And for CMB, we have the most powerful tool is the power spectrum. And right here, the counterpart in particle physics is, well, also well-known, the Fox-Wolfram moment or FW moment. Therefore, with this dictionary between particle physics and the CMB, we are able to study the power spectrum of an event and also potentially multi-spectrum. Or if you look at the power spectrum of events, just like CMB, so information get encoded in these acoustic peaks, we also have, well, I mean, acoustic peaks in collider events. So lower-level, sorry, low-L modes now encodes particle-leveling kinematics because it's like large angular separation. And when we go to higher and higher tail, this will be dominated by QCD effects. So it's very interesting and we can build. So we did a lot of numerical study and the most fruitful one is actually, or wrap up everything is the Higgs width measurement at future Higgs factory mode. So to do that, we need to use like, well, these methods and eventually turn into measuring like, say, Higgs to WWDKs or so. So using like two-jet or four-jet final state. We build a lot of machine learning classifiers, but we notice that, well, when go to event level, the performance gets much better and eventually we can reach like from like right here to right here and 80% improvement. Okay, even using machine learning. Okay, if we go from jet input only to event level input. So we may simply conclude that event level is the future for precision physics. Thank you.
 Hi, I'm Langston Lee from HKEUSD.  I'm very glad I can speak on behalf of my collaborators  about Go Beyond Jet Level Information at Precision Era.  So as we all know, if we are lucky,  so we are moving to a precision frontier in next decades,  leading by those high energy electron colliders.  And the primary goal of this phase,  or well, era is to measure electrical weak and Higgs  very precisely, and eventually we are dealing with WZ  and, well, I mean, Higgs-related decays.  And as you can see right here,  most of these decays are dominated by, well,  I mean, hydronic modes involving hydrants in the planet state.  So which is a must, okay, if we want to know very well  these sector, we need to know these hydronic modes  and usually that's a bottleneck because we are relying  on the definition of jets when measuring these modes  and AKA jet clustering.  And usually that would not be satisfying  when facing with the need of precision.  For instance, we can have an E to Z, Z to four jet event.  If we project this example event into theta-5 plane,  and we can see that on the other half of a plane,  hydrants from different Z get clustered into same jet,  which means clearly clustering distorts information  from truth level.  And even when the distortion is not significant,  we will have information loss because many dimension  of information is well gone after clustering.  So in order to compensate the effect,  we'd better think about how to put the whole event  without loss into the analysis framework.  And one effective way is to like treat the event  as an image.  For instance, to better understand this, we project  while cumulative events into the sphere after,  well, I mean, several pre-processing steps,  but after pre-processing independent of jet prediction,  we can see, well, for E to QQ back-to-back event,  we can see two patterns go back-to-back,  well, two energetic flows, looks like two jets, fine.  And for E to ZZ, where one ZZ to two jets,  we find the typical angular separation  between these two quarks or jets,  therefore forming a halo-like structure.  So in this way, we can achieve the no-lose of information  and the maximum input we can get.  And when studying this, we notice the close resemblance  between such event level projection and, well,  I mean, the all-sky CMB map well-studied in cosmology.  So because they are all projections of, like, say,  either energy, temperature, or you can say, PT, charge,  whatever you want on the detector sphere  or the celestial sphere, a spherical image.  And for CMB, we have the most powerful tool  is the power spectrum.  And right here, the counterpart in particle physics  is, well, also well-known,  the Fox-Wolfram moment or FW moment.  Therefore, with this dictionary  between particle physics and the CMB,  we are able to study the power spectrum of an event  and also potentially multi-spectrum.  Or if you look at the power spectrum of events,  just like CMB, so information get encoded  in these acoustic peaks, we also have, well,  I mean, acoustic peaks in collider events.  So lower-level, sorry, low-L modes now encodes  particle-leveling kinematics  because it's like large angular separation.  And when we go to higher and higher tail,  this will be dominated by QCD effects.  So it's very interesting and we can build.  So we did a lot of numerical study  and the most fruitful one is actually,  or wrap up everything is the Higgs width measurement  at future Higgs factory mode.  So to do that, we need to use like, well, these methods  and eventually turn into measuring like, say, Higgs  to WWDKs or so.  So using like two-jet or four-jet final state.  We build a lot of machine learning classifiers,  but we notice that, well, when go to event level,  the performance gets much better  and eventually we can reach like from like right here  to right here and 80% improvement.  Okay, even using machine learning.  Okay, if we go from jet input only to event level input.  So we may simply conclude that event level  is the future for precision physics.  Thank you.
EventLevel_5min_0_7607.png EventLevel_5min_7608_7859.png EventLevel_5min_7860_8099.png EventLevel_5min_8100_8231.png EventLevel_5min_8232_8351.png EventLevel_5min_8352_8483.png EventLevel_5min_8484_8603.png EventLevel_5min_8604_8735.png EventLevel_5min_8736_8851.png