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Abstract Multijet events at large transverse momentum ( $$p_{\textrm{T}}$$ p T ) are measured at $$\sqrt{s}=13\,\text {TeV} $$ s = 13 TeV using data recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of $$36.3{\,\text {fb}^{-1}} $$ 36.3 fb - 1 . The multiplicity of jets with $$p_{\textrm{T}} >50\,\text {GeV} $$ p T > 50 GeV that are produced in association with a high- $$p_{\textrm{T}}$$ p T dijet system is measured in various ranges of the $$p_{\textrm{T}}$$ p T of the jet with the highest transverse momentum and as a function of the azimuthal angle difference $$\varDelta \phi _{1,2}$$ Δ ϕ 1 , 2 between the two highest $$p_{\textrm{T}}$$ p T jets in the dijet system. The differential production cross sections are measured as a function of the transverse momenta of the four highest $$p_{\textrm{T}}$$ p T jets. The measurements are compared with leading and next-to-leading order matrix element calculations supplemented with simulations of parton shower, hadronization, and multiparton interactions. In addition, the measurements are compared with next-to-leading order matrix element calculations combined with transverse-momentum dependent parton densities and transverse-momentum dependent parton shower.
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Deformation of Jets Induced by Ambient Medium Flow
The evolution of jets showers in high energy nuclear collisions is influenced in various ways by the presence of a surrounding medium. The interaction of jet constituents with the medium can happen during the partonic stage of the jet, during hadronization, and even during its hadronic stage. We demonstrate how flow of the ambient medium in a direction transverse to the jet can introduce both dipole and quadrupole defomations. We propose to analyze then= 1 andn= 2 harmonic deformations of soft and semi-hard hadrons or subjets in a jet with respect to the jet core using the method ofq-vectors. We discuss simulations which show how the transverse shapes and their preferred angles evolve when the ambient environment of jets changes from the vacuum to a parton medium without flow and finally to a medium with various rates of transverse flow. Our study includes the effects of both flow during the development of the parton shower and hadronization. The existence of dipole deformations, and the correlation of the angles of dipole and quadrupole deformations could constitute promising experimental signals for the presence and size of ambient transverse flow.
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- PAR ID:
- 10656113
- Editor(s):
- Chujo, T; Hirano, T; Itakura, K; Oyama, K; Tachibana, Y
- Publisher / Repository:
- Hard Probes 2024
- Date Published:
- Journal Name:
- EPJ Web of Conferences
- Volume:
- 339
- ISSN:
- 2100-014X
- Page Range / eLocation ID:
- 02005
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1051/epjconf/202533902005
