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Title: Identifying a new particle with jet substructures

Abstract

Here, we investigate a potential of determining properties of a new heavy resonance of mass O(1)TeV which decays to collimated jets via heavy Standard Model intermediary states, exploiting jet substructure techniques. Employing the Z gauge boson as a concrete example for the intermediary state, we utilize a "merged jet" defined by a large jet size to capture the two quarks from its decay. The use of the merged jet bene ts the identification of a Z-induced jet as a single, reconstructed object without any combinatorial ambiguity. We also find that jet substructure procedures may enhance features in some kinematic observables formed with subjet four-momenta extracted from a merged jet. This observation motivates us to feed subjet momenta into the matrix elements associated with plausible hypotheses on the nature of the heavy resonance, which are further processed to construct a matrix element method (MEM)-based observable. For both moderately and highly boosted Z bosons, we demonstrate that the MEM in combination with jet substructure techniques can be a very powerful tool for identifying its physical properties. Finally, we discuss effects from choosing different jet sizes for merged jets and jet-grooming parameters upon the MEM analyses.

Authors:
 [1];  [2];  [3];  [4];  [5];  [6]
  1. Univ. of Tokyo (Japan). Kavli IPMU (WPI)
  2. Univ. of Florida, Gainesville, FL (United States). Dept. of Physics; European Organization for Nuclear Research (CERN), Geneva (Switzerland)
  3. Center for Theoretical Physics of the Universe, Daejeon (Korea). Inst. for Basic Science (IBS); Postech, Pohang (Korea). Dept. of Physics
  4. Univ. of Kansas, Lawrence, KS (United States). Dept. of Physics and Astronomy; Univ. of Pittsburgh, PA (United States). Pittsburgh Particle Physics, Astrophysics and Cosmology Center and Dept. of Physics and Astronomy
  5. Center for Theoretical Physics of the Universe, Daejeon (Korea). Inst. for Basic Science (IBS); Korea Advanced Inst. Science and Technology (KAIST), Daejeon (Korea, Republic of). Dept. of Physics
  6. Center for Theoretical Physics of the Universe, Daejeon (Korea). Inst. for Basic Science (IBS)
Publication Date:
Research Org.:
Univ. of Kansas, Lawrence, KS (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1360739
Grant/Contract Number:
SC0007863
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2017; Journal Issue: 1; Journal ID: ISSN 1029-8479
Publisher:
Springer Berlin
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Deep Inelastic Scattering (Phenomenology); Jets

Citation Formats

Han, Chengcheng, Kim, Doojin, Kim, Minho, Kong, Kyoungchul, Lim, Sung Hak, and Park, Myeonghun. Identifying a new particle with jet substructures. United States: N. p., 2017. Web. doi:10.1007/JHEP01(2017)027.
Han, Chengcheng, Kim, Doojin, Kim, Minho, Kong, Kyoungchul, Lim, Sung Hak, & Park, Myeonghun. Identifying a new particle with jet substructures. United States. doi:10.1007/JHEP01(2017)027.
Han, Chengcheng, Kim, Doojin, Kim, Minho, Kong, Kyoungchul, Lim, Sung Hak, and Park, Myeonghun. Mon . "Identifying a new particle with jet substructures". United States. doi:10.1007/JHEP01(2017)027. https://www.osti.gov/servlets/purl/1360739.
@article{osti_1360739,
title = {Identifying a new particle with jet substructures},
author = {Han, Chengcheng and Kim, Doojin and Kim, Minho and Kong, Kyoungchul and Lim, Sung Hak and Park, Myeonghun},
abstractNote = {Here, we investigate a potential of determining properties of a new heavy resonance of mass O(1)TeV which decays to collimated jets via heavy Standard Model intermediary states, exploiting jet substructure techniques. Employing the Z gauge boson as a concrete example for the intermediary state, we utilize a "merged jet" defined by a large jet size to capture the two quarks from its decay. The use of the merged jet bene ts the identification of a Z-induced jet as a single, reconstructed object without any combinatorial ambiguity. We also find that jet substructure procedures may enhance features in some kinematic observables formed with subjet four-momenta extracted from a merged jet. This observation motivates us to feed subjet momenta into the matrix elements associated with plausible hypotheses on the nature of the heavy resonance, which are further processed to construct a matrix element method (MEM)-based observable. For both moderately and highly boosted Z bosons, we demonstrate that the MEM in combination with jet substructure techniques can be a very powerful tool for identifying its physical properties. Finally, we discuss effects from choosing different jet sizes for merged jets and jet-grooming parameters upon the MEM analyses.},
doi = {10.1007/JHEP01(2017)027},
journal = {Journal of High Energy Physics (Online)},
number = 1,
volume = 2017,
place = {United States},
year = {Mon Jan 09 00:00:00 EST 2017},
month = {Mon Jan 09 00:00:00 EST 2017}
}

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