Conveners
QCD: 1
- Giovanni Stagnitto (University of Zurich)
QCD: 2
- Aditya Pathak (University of Manchester)
QCD: 3
- Juergen Reuter (DESY Hamburg, Germany)
We present the first anti-kT jet spectrum and substructure measurements using the archived ALEPH e+e- data taken in 1994 at a center of mass energy of sqrt(s) = 91.2 GeV. Jets are reconstructed with the anti-kT algorithm with a resolution parameter of 0.4. It is the cleanest test of jets and QCD without the complication of hadronic initial states. The fixed center-of-mass energy also allows...
Energy Correlators (EEC) have recently received great interest both theoretically and experimentally. In particular, the study of EECs in jet substructure has gained deeper understanding with the advent of the light-ray operator product expansion. In this talk, based on this progress, we propose a ratio observable named “celestial non-gaussianity”, which roughly is the ratio between...
Track functions describe the collective effect of the fragmentation of quarks and gluons into charged hadrons, making them a key ingredient for jet substructure measurements at hadron colliders where track-based measurements offer superior angular resolution. Unlike DGLAP, the evolution of track functions incorporates correlations between final-state hadrons, and is hence non-linear. We derive...
Jet angularities are an important class of jet substructure observables
investigated at the LHC. In this talk I will focus the comparison of theoretical
predictions against recent measurements from the CMS experiment [1]. I will
present calculations at NLO+NLL' based on [2, 3], in hadronic dijet and
Z+jet events. Where applicable, the effect of soft drop grooming is included....
We consider the issue of meaningfully assigning a flavor label to a jet and we show that modern jet substructure techniques can give us new ways to tackle this problem.
On the one hand, we introduce a novel fragmentation-function framework that allows one to connect a flavor definition in the deep UV, where partons live, to an IR definition, where jets live. The IR definition involves the...
Quantum chromodynamics is the theory of the strong interaction between quarks and gluons; the coupling strength of the interaction, $\alpha_S$, is the least precisely-known of all interactions in nature. An extraction of the strong coupling from the radiation pattern within jets would provide a complementary approach to conventional extractions from jet production rates and hadronic event...
Identifying the flavour of the experimentally reconstructed hadronic jets is critical to pinpoint specific scattering processes and reject background processes. Jet measurements at the LHC are almost universally performed using the anti-$k_T$ algorithm, however no approach exists to define the jet flavour for this algorithm that is infrared and collinear (IRC) safe. In this talk, we propose a...
Observables computed on jets groomed with mMDT, or equivalently Soft Drop with $\beta=0$, benefit from reduced sensitivity to pileup, underlying event, and hadronisation, compared to observables computed on un-groomed jets. Observables computed on groomed jets are therefore good candidates for direct comparison between perturbative QCD predictions and measurements.
Focusing on quark...
Effects of hadronization and underlying event on jet substructure observables must be accurately quantified for precision QCD measurements such as the strong coupling constant and the top quark mass. While these effects have long been studied for ungroomed observables such as the jet mass and jet $p_T$, they are significantly more complicated in groomed observables. In this work we employ a...
Many New Physics searches and QCD precision measurements at particle colliders involve the study of jet substructure for final state hadrons. While traditionally the state of the art for studying jets at particle colliders have been event shape observables, recently it has been better understood that measuring correlation functions of energy flow operators inside a jet can be a very powerful...
