Measurements of the groomed jet radius and momentum splitting fraction with the soft drop and dynamical grooming algorithms in pp collisions at $\sqrt{s}=5.02$ TeV

This article presents measurements of the groomed jet radius and momentum splitting fraction in pp collisions at $\sqrt{s}=5.02$ TeV with the ALICE detector at the Large Hadron Collider. Inclusive charged-particle jets are reconstructed at midrapidity using the anti-$k_{\rm{T}}$ algorithm for transverse momentum $60<~ p_{\mathrm{T}}^{\rm{ch\; jet}}<~80$ GeV/$c$. We report results using two different grooming algorithms: soft drop and, for the first time, dynamical grooming. For each grooming algorithm, a variety of grooming settings are used in order to explore the impact of collinear radiation on these jet substructure observables. These results are compared to perturbative calculations that include resummation of large logarithms at all orders in the strong coupling constant. We find good agreement of the theoretical predictions with the data for all grooming settings considered.

 

Submitted to: JHEP
e-Print: arXiv:2204.10246 | PDF | inSPIRE
Figure group

Figure 1

Graphical representation of the angularly-ordered Cambridge--Aachen reclustering of jet constituentsand subsequent grooming procedure,with the identified splitting denoted in black and the splittings that were groomed away in light blue

Figure 2

ALICE measurements of \zg{} distributions in \pp{} collisions at $\sqrt{s}=5.02\;$ TeV with soft drop for three values of the grooming parameter $\beta$, compared with PYTHIA8 Monash 2013~ calculations.

Figure 3

ALICE measurements of \tg{} distributions in \pp{} collisions at $\sqrt{s}=5.02\;$ TeV with soft drop for three values of the grooming parameter $\beta$, compared with PYTHIA8 Monash 2013~ calculations.

Figure 4

ALICE measurements of \tg{} distributions in \pp{} collisions at $\sqrt{s}=5.02$ TeV withsoft drop, compared with NLL$^\prime$ predictions carried out with SCET ~ andcorrected for non-perturbative effects using either PYTHIA8~or Herwig7~. The distributions are normalized such that theintegral of the perturbative region defined by $\tg{} > \tgNP{}$(to the right of the dashed vertical blue line) is unity The non-perturbative scale in Eq.~\ref{eq:8} is taken to be $\Lambda=1\;\GeVc$ In determining the normalization, intervals that overlap with the dashed blue line are considered to be in the non-perturbative (left) region.

Figure 5

ALICE measurements of \zg{} distributions in \pp{} collisions at $\sqrt{s}=5.02\;$ TeV with dynamical grooming~ for three values of thegrooming parameter $a$, compared with PYTHIA8 Monash 2013~ calculations.

Figure 6

ALICE measurements of \tg{} distributions in \pp{} collisions at $\sqrt{s}=5.02\;$ TeV with dynamical grooming~ for three values of thegrooming parameter $a$, compared with PYTHIA8 Monash 2013~ calculations.

Figure 7

ALICE measurements of \zg{} distributions in \pp{} collisions at $\sqrt{s}=5.02\;$ TeV with dynamical groomingfor two values of thegrooming parameter $a$, compared with pQCD calculations~.

Figure 8

ALICE measurements of \tg{} distributions in \pp{} collisions at $\sqrt{s}=5.02\;$ TeV with dynamical grooming for two values of thegrooming parameter $a$, compared with pQCD calculations~.