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Title: Higgs and Z assisted stop searches at hadron colliders

Abstract

Current searches for the light top squark (stop) mostly focus on the decay channels of \( \tilde{t}\to t{\chi}_1^0 \) or \( \tilde{t}\to b{\chi}_1^{\pm}\to bW{\chi}_1^0 \) , leading to Open image in new window final states for stop pair productions at the LHC. However, in supersymmetric scenarios with light neutralinos and charginos other than the neutralino lightest supersymmetric particle (LSP), more than one decay mode of the stop could be dominant. While those new decay modes could significantly weaken the current stop search limits at the LHC, they also offer alternative discovery channels for stop searches. In this paper, we studied the scenario with light Higgsino next-to-LSPs (NLSPs) and Bino LSP. The light stop decays primarily via \( {\tilde{t}}_1\to t{\chi}_2^0/{\chi}_3^0 \) , with the neutralinos subsequent decaying to a Z boson or a Higgs boson: χ 2° /χ 3 ° → χ 1 ° h/Z. Pair production of light stops at the LHC leads to final states of Open image in new window or Open image in new window . We consider three signal regions: one charged lepton (1ℓ), two opposite sign charged leptons (2 OS ℓ) and at least three charged leptons (≥3ℓ). We found that the 1ℓ signal regionmore » of channel Open image in new window has the best reach sensitivity for light stop searches. For 14 TeV LHC with 300 fb -1 integrated luminosity, a stop mass up to 900 GeV can be discovered at 5σ significance, or up to 1050 GeV can be excluded at 95% C.L. Combining all three decay channels for 1ℓ signal region extends the reach for about 100–150 GeV. We also studied the stop reach at the 100 TeV pp collider with 3 ab -1 luminosity, with discovery and exclusion reach being 6 TeV and 7 TeV, respectively.« less

Authors:
 [1]; ORCiD logo [2]
  1. Univ. of Arizona, Tucson, AZ (United States). Dept. of Physics
  2. Univ. of Arizona, Tucson, AZ (United States). Steward Observatory
Publication Date:
Research Org.:
Univ. of Arizona, Tucson, AZ (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1507710
Grant/Contract Number:  
[FG02-04ER41298]
Resource Type:
Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
[Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2018; Journal Issue: 5]; Journal ID: ISSN 1029-8479
Publisher:
Springer Berlin
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Supersymmetry Phenomenology

Citation Formats

Su, Shufang, and Zhang, Huanian. Higgs and Z assisted stop searches at hadron colliders. United States: N. p., 2018. Web. doi:10.1007/jhep05(2018)135.
Su, Shufang, & Zhang, Huanian. Higgs and Z assisted stop searches at hadron colliders. United States. doi:10.1007/jhep05(2018)135.
Su, Shufang, and Zhang, Huanian. Tue . "Higgs and Z assisted stop searches at hadron colliders". United States. doi:10.1007/jhep05(2018)135. https://www.osti.gov/servlets/purl/1507710.
@article{osti_1507710,
title = {Higgs and Z assisted stop searches at hadron colliders},
author = {Su, Shufang and Zhang, Huanian},
abstractNote = {Current searches for the light top squark (stop) mostly focus on the decay channels of \( \tilde{t}\to t{\chi}_1^0 \) or \( \tilde{t}\to b{\chi}_1^{\pm}\to bW{\chi}_1^0 \) , leading to Open image in new window final states for stop pair productions at the LHC. However, in supersymmetric scenarios with light neutralinos and charginos other than the neutralino lightest supersymmetric particle (LSP), more than one decay mode of the stop could be dominant. While those new decay modes could significantly weaken the current stop search limits at the LHC, they also offer alternative discovery channels for stop searches. In this paper, we studied the scenario with light Higgsino next-to-LSPs (NLSPs) and Bino LSP. The light stop decays primarily via \( {\tilde{t}}_1\to t{\chi}_2^0/{\chi}_3^0 \) , with the neutralinos subsequent decaying to a Z boson or a Higgs boson: χ 2° /χ 3 ° → χ 1 ° h/Z. Pair production of light stops at the LHC leads to final states of Open image in new window or Open image in new window . We consider three signal regions: one charged lepton (1ℓ), two opposite sign charged leptons (2 OS ℓ) and at least three charged leptons (≥3ℓ). We found that the 1ℓ signal region of channel Open image in new window has the best reach sensitivity for light stop searches. For 14 TeV LHC with 300 fb-1 integrated luminosity, a stop mass up to 900 GeV can be discovered at 5σ significance, or up to 1050 GeV can be excluded at 95% C.L. Combining all three decay channels for 1ℓ signal region extends the reach for about 100–150 GeV. We also studied the stop reach at the 100 TeV pp collider with 3 ab-1 luminosity, with discovery and exclusion reach being 6 TeV and 7 TeV, respectively.},
doi = {10.1007/jhep05(2018)135},
journal = {Journal of High Energy Physics (Online)},
number = [5],
volume = [2018],
place = {United States},
year = {2018},
month = {5}
}

Journal Article:
Free Publicly Available Full Text
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Figures / Tables:

Table 1 Table 1: Mass parameters and mass spectrum of SUSY particles for one benchmark point. All masses are in units of GeV.

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