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Title: Dissecting jets and missing energy searches using $n$-body extended simplified models

Abstract

Simplified Models are a useful way to characterize new physics scenarios for the LHC. Particle decays are often represented using non-renormalizable operators that involve the minimal number of fields required by symmetries. Generalizing to a wider class of decay operators allows one to model a variety of final states. This approach, which we dub the $n$-body extension of Simplified Models, provides a unifying treatment of the signal phase space resulting from a variety of signals. In this paper, we present the first application of this framework in the context of multijet plus missing energy searches. The main result of this work is a global performance study with the goal of identifying which set of observables yields the best discriminating power against the largest Standard Model backgrounds for a wide range of signal jet multiplicities. Our analysis compares combinations of one, two and three variables, placing emphasis on the enhanced sensitivity gain resulting from non-trivial correlations. Utilizing boosted decision trees, we compare and classify the performance of missing energy, energy scale and energy structure observables. We demonstrate that including an observable from each of these three classes is required to achieve optimal performance. In conclusion, this work additionally serves to establishmore » the utility of $n$-body extended Simplified Models as a diagnostic for unpacking the relative merits of different search strategies, thereby motivating their application to new physics signatures beyond jets and missing energy.« less

Authors:
 [1];  [2];  [3];  [4];  [4];  [4]
  1. Univ. of Oregon, Eugene, OR (United States)
  2. Univ. of Melbourne (Australia)
  3. Johannes Gutenberg-Univ., Mainz (Germany)
  4. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1287383
Report Number(s):
FERMILAB-PUB-16-122-E; arXiv:1605.01416
Journal ID: ISSN 1029-8479; 1455878
Grant/Contract Number:
AC02-07CH11359
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: 2016; Journal Issue: 8; Journal ID: ISSN 1029-8479
Publisher:
Springer Berlin
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Beyond Standard Model; Hadron-Hadron scattering (experiments); Dark matter; supersymmetry

Citation Formats

Cohen, Timothy, Dolan, Matthew J., El Hedri, Sonia, Hirschauer, James, Tran, Nhan, and Whitbeck, Andrew. Dissecting jets and missing energy searches using $n$-body extended simplified models. United States: N. p., 2016. Web. doi:10.1007/JHEP08(2016)038.
Cohen, Timothy, Dolan, Matthew J., El Hedri, Sonia, Hirschauer, James, Tran, Nhan, & Whitbeck, Andrew. Dissecting jets and missing energy searches using $n$-body extended simplified models. United States. doi:10.1007/JHEP08(2016)038.
Cohen, Timothy, Dolan, Matthew J., El Hedri, Sonia, Hirschauer, James, Tran, Nhan, and Whitbeck, Andrew. Thu . "Dissecting jets and missing energy searches using $n$-body extended simplified models". United States. doi:10.1007/JHEP08(2016)038. https://www.osti.gov/servlets/purl/1287383.
@article{osti_1287383,
title = {Dissecting jets and missing energy searches using $n$-body extended simplified models},
author = {Cohen, Timothy and Dolan, Matthew J. and El Hedri, Sonia and Hirschauer, James and Tran, Nhan and Whitbeck, Andrew},
abstractNote = {Simplified Models are a useful way to characterize new physics scenarios for the LHC. Particle decays are often represented using non-renormalizable operators that involve the minimal number of fields required by symmetries. Generalizing to a wider class of decay operators allows one to model a variety of final states. This approach, which we dub the $n$-body extension of Simplified Models, provides a unifying treatment of the signal phase space resulting from a variety of signals. In this paper, we present the first application of this framework in the context of multijet plus missing energy searches. The main result of this work is a global performance study with the goal of identifying which set of observables yields the best discriminating power against the largest Standard Model backgrounds for a wide range of signal jet multiplicities. Our analysis compares combinations of one, two and three variables, placing emphasis on the enhanced sensitivity gain resulting from non-trivial correlations. Utilizing boosted decision trees, we compare and classify the performance of missing energy, energy scale and energy structure observables. We demonstrate that including an observable from each of these three classes is required to achieve optimal performance. In conclusion, this work additionally serves to establish the utility of $n$-body extended Simplified Models as a diagnostic for unpacking the relative merits of different search strategies, thereby motivating their application to new physics signatures beyond jets and missing energy.},
doi = {10.1007/JHEP08(2016)038},
journal = {Journal of High Energy Physics (Online)},
number = 8,
volume = 2016,
place = {United States},
year = {Thu Aug 04 00:00:00 EDT 2016},
month = {Thu Aug 04 00:00:00 EDT 2016}
}

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