Uncovering new Higgses in the LHC analyses of differential t t ¯ $$ t\overline{t} $$ cross sections

Abstract Statistically significant tensions between the Standard Model (SM) predictions and the measured lepton distributions in differential top cross-sections emerged in LHC Run 1 data and became even more pronounced in Run 2 analyses. Due to the level of sophistication of the SM predictions and t...

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Main Authors: Sumit Banik, Guglielmo Coloretti, Andreas Crivellin, Bruce Mellado
Format: Article
Language:English
Published: SpringerOpen 2025-01-01
Series:Journal of High Energy Physics
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Online Access:https://doi.org/10.1007/JHEP01(2025)155
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author Sumit Banik
Guglielmo Coloretti
Andreas Crivellin
Bruce Mellado
author_facet Sumit Banik
Guglielmo Coloretti
Andreas Crivellin
Bruce Mellado
author_sort Sumit Banik
collection DOAJ
description Abstract Statistically significant tensions between the Standard Model (SM) predictions and the measured lepton distributions in differential top cross-sections emerged in LHC Run 1 data and became even more pronounced in Run 2 analyses. Due to the level of sophistication of the SM predictions and the performance of the ATLAS and CMS detectors, this is very remarkable. Therefore, one should seriously consider the possibility that these measurements are contaminated by beyond-the-SM contributions. In this article, we use the differential lepton distributions from the latest ATLAS t t ¯ $$ t\overline{t} $$ analysis to study a new physics benchmark model motivated by existing indications for new Higgses: a new scalar H is produced via gluon fusion and decays to S ′ (95 GeV) and S (152 GeV), which subsequently decay to b b ¯ $$ b\overline{b} $$ and WW, respectively. In this setup, the total 𝜒2 is reduced, compared to the SM, resulting in ∆χ 2 = 34 to ∆χ 2 = 158, corresponding to a significance of 5.8σ to 13σ, depending on the SM simulation used. Notably, allowing m S to vary, the combination of the distributions points towards m S ≈ 150 GeV, which is consistent with the existing γγ and WW signals, rendering a mismodelling of the SM unlikely. Averaging the results of the different SM predictions, σ(pp → H → SS ′) × Br(S → WW) × Br(S ′ → bb) ≈ 9pb is preferred. Assuming that S ′ is SM-like, the 95 GeV γγ excess can be explained if S decays dominantly to W bosons. That latter suggests that S is the neutral component of the SU(2) L triplet with hypercharge 0.
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spelling doaj-art-10be4f57f8f44a9bbf7819a0bbff8e8e2025-02-09T12:07:32ZengSpringerOpenJournal of High Energy Physics1029-84792025-01-012025111510.1007/JHEP01(2025)155Uncovering new Higgses in the LHC analyses of differential t t ¯ $$ t\overline{t} $$ cross sectionsSumit Banik0Guglielmo Coloretti1Andreas Crivellin2Bruce Mellado3Physik-Institut, Universität ZürichPhysik-Institut, Universität ZürichPhysik-Institut, Universität ZürichSchool of Physics and Institute for Collider Particle Physics, University of the WitwatersrandAbstract Statistically significant tensions between the Standard Model (SM) predictions and the measured lepton distributions in differential top cross-sections emerged in LHC Run 1 data and became even more pronounced in Run 2 analyses. Due to the level of sophistication of the SM predictions and the performance of the ATLAS and CMS detectors, this is very remarkable. Therefore, one should seriously consider the possibility that these measurements are contaminated by beyond-the-SM contributions. In this article, we use the differential lepton distributions from the latest ATLAS t t ¯ $$ t\overline{t} $$ analysis to study a new physics benchmark model motivated by existing indications for new Higgses: a new scalar H is produced via gluon fusion and decays to S ′ (95 GeV) and S (152 GeV), which subsequently decay to b b ¯ $$ b\overline{b} $$ and WW, respectively. In this setup, the total 𝜒2 is reduced, compared to the SM, resulting in ∆χ 2 = 34 to ∆χ 2 = 158, corresponding to a significance of 5.8σ to 13σ, depending on the SM simulation used. Notably, allowing m S to vary, the combination of the distributions points towards m S ≈ 150 GeV, which is consistent with the existing γγ and WW signals, rendering a mismodelling of the SM unlikely. Averaging the results of the different SM predictions, σ(pp → H → SS ′) × Br(S → WW) × Br(S ′ → bb) ≈ 9pb is preferred. Assuming that S ′ is SM-like, the 95 GeV γγ excess can be explained if S decays dominantly to W bosons. That latter suggests that S is the neutral component of the SU(2) L triplet with hypercharge 0.https://doi.org/10.1007/JHEP01(2025)155Multi-Higgs ModelsSpecific BSM Phenomenology
spellingShingle Sumit Banik
Guglielmo Coloretti
Andreas Crivellin
Bruce Mellado
Uncovering new Higgses in the LHC analyses of differential t t ¯ $$ t\overline{t} $$ cross sections
Journal of High Energy Physics
Multi-Higgs Models
Specific BSM Phenomenology
title Uncovering new Higgses in the LHC analyses of differential t t ¯ $$ t\overline{t} $$ cross sections
title_full Uncovering new Higgses in the LHC analyses of differential t t ¯ $$ t\overline{t} $$ cross sections
title_fullStr Uncovering new Higgses in the LHC analyses of differential t t ¯ $$ t\overline{t} $$ cross sections
title_full_unstemmed Uncovering new Higgses in the LHC analyses of differential t t ¯ $$ t\overline{t} $$ cross sections
title_short Uncovering new Higgses in the LHC analyses of differential t t ¯ $$ t\overline{t} $$ cross sections
title_sort uncovering new higgses in the lhc analyses of differential t t ¯ t overline t cross sections
topic Multi-Higgs Models
Specific BSM Phenomenology
url https://doi.org/10.1007/JHEP01(2025)155
work_keys_str_mv AT sumitbanik uncoveringnewhiggsesinthelhcanalysesofdifferentialtttoverlinetcrosssections
AT guglielmocoloretti uncoveringnewhiggsesinthelhcanalysesofdifferentialtttoverlinetcrosssections
AT andreascrivellin uncoveringnewhiggsesinthelhcanalysesofdifferentialtttoverlinetcrosssections
AT brucemellado uncoveringnewhiggsesinthelhcanalysesofdifferentialtttoverlinetcrosssections