First shot of the smoking gun: probing the electroweak phase transition in the 2HDM with novel searches for A → ZH in + t t ¯ $$ {\ell}^{+}{\ell}^{-}t\overline{t} $$ and ννb b ¯ $$ \nu \nu b\overline{b} $$ final states

Thomas Biekötter (Institute for Theoretical Physics, Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, Karlsruhe, 76131, Germany) ; Sven Heinemeyer (Instituto de Física Teórica UAM-CSIC, Cantoblanco, Madrid, 28049, Spain) ; Jose No (Instituto de Física Teórica UAM-CSIC, Cantoblanco, Madrid, 28049, Spain; Departamento de Física Teórica, Universidad Autónoma de Madrid (UAM), Campus de Cantoblanco, Madrid, 28049, Spain) ; Kateryna Radchenko (Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg, 22607, Germany) ; María Olea Romacho (Laboratoire de Physique de l’Ecole Normale Supérieure, ENS, Universite PSL, CNRS, Sorbonne Université, Université Paris Cité, Paris, F-75005, France) ; et al. - Show all 6 authors

Recently the ATLAS collaboration has reported the first results of searches for heavy scalar resonances decaying into a Z boson and a lighter new scalar resonance, where the Z boson decays leptonically and the lighter scalar decays into a top-quark pair, giving rise to + t t ¯ $$ {\ell}^{+}{\ell}^{-}t\overline{t} $$ final states. This had previously been identified as a smoking-gun signature at the LHC for a first-order electroweak phase transition (FOEWPT) within the framework of two Higgs doublet models (2HDMs). In addition, ATLAS also presented new limits where the Z boson decays into pairs of neutrinos and the lighter scalar resonance into bottom-quark pairs, giving rise to the ννb b ¯ $$ \nu \nu b\overline{b} $$ final state. We analyze the impact of these new searches on the 2HDM parameter space, with emphasis on their capability to probe currently allowed 2HDM regions featuring a strong FOEWPT. We also study the complementarity of these new searches with other LHC probes that could target the FOEWPT region of the 2HDM. Remarkably, the ATLAS search in the + t t ¯ $$ {\ell}^{+}{\ell}^{-}t\overline{t} $$ final state shows a local 2.85 σ excess (for masses of about 650 GeV and 450 GeV for the heavy and light resonance) in the 2HDM parameter region that would yield a FOEWPT in the early universe, which could constitute the first experimental hint of baryogenesis at the electroweak scale. We analyze the implications of this excess, and discuss the detectability prospects for the associated gravitational wave signal from the FOEWPT. Furthermore, we project the sensitivity reach of the + t t ¯ $$ {\ell}^{+}{\ell}^{-}t\overline{t} $$ signature for the upcoming runs of the LHC. Finally, we introduce the python package thdmTools, a state-of-art tool for the exploration of the 2HDM.

{
  "_oai": {
    "updated": "2024-04-25T00:32:38Z", 
    "id": "oai:repo.scoap3.org:82882", 
    "sets": [
      "JHEP"
    ]
  }, 
  "authors": [
    {
      "affiliations": [
        {
          "country": "Germany", 
          "value": "Institute for Theoretical Physics, Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, Karlsruhe, 76131, Germany", 
          "organization": "Karlsruhe Institute of Technology"
        }
      ], 
      "surname": "Biek\u00f6tter", 
      "email": "thomas.biekoetter@kit.edu", 
      "full_name": "Biek\u00f6tter, Thomas", 
      "given_names": "Thomas"
    }, 
    {
      "affiliations": [
        {
          "country": "Spain", 
          "value": "Instituto de F\u00edsica Te\u00f3rica UAM-CSIC, Cantoblanco, Madrid, 28049, Spain", 
          "organization": "Instituto de F\u00edsica Te\u00f3rica UAM-CSIC"
        }
      ], 
      "surname": "Heinemeyer", 
      "email": "sven.heinemeyer@cern.ch", 
      "full_name": "Heinemeyer, Sven", 
      "given_names": "Sven"
    }, 
    {
      "affiliations": [
        {
          "country": "Spain", 
          "value": "Instituto de F\u00edsica Te\u00f3rica UAM-CSIC, Cantoblanco, Madrid, 28049, Spain", 
          "organization": "Instituto de F\u00edsica Te\u00f3rica UAM-CSIC"
        }, 
        {
          "country": "Spain", 
          "value": "Departamento de F\u00edsica Te\u00f3rica, Universidad Aut\u00f3noma de Madrid (UAM), Campus de Cantoblanco, Madrid, 28049, Spain", 
          "organization": "Universidad Aut\u00f3noma de Madrid (UAM)"
        }
      ], 
      "surname": "No", 
      "email": "josemiguel.no@uam.es", 
      "full_name": "No, Jose", 
      "given_names": "Jose"
    }, 
    {
      "affiliations": [
        {
          "country": "Germany", 
          "value": "Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg, 22607, Germany", 
          "organization": "Deutsches Elektronen-Synchrotron DESY"
        }
      ], 
      "surname": "Radchenko", 
      "email": "kateryna.radchenko@desy.de", 
      "full_name": "Radchenko, Kateryna", 
      "given_names": "Kateryna"
    }, 
    {
      "affiliations": [
        {
          "country": "France", 
          "value": "Laboratoire de Physique de l\u2019Ecole Normale Sup\u00e9rieure, ENS, Universite PSL, CNRS, Sorbonne Universit\u00e9, Universit\u00e9 Paris Cit\u00e9, Paris, F-75005, France", 
          "organization": "Laboratoire de Physique de l\u2019Ecole Normale Sup\u00e9rieure, ENS, Universite PSL, CNRS, Sorbonne Universit\u00e9, Universit\u00e9 Paris Cit\u00e9"
        }
      ], 
      "surname": "Olea Romacho", 
      "email": "mariaolalla.olearomacho@phys.ens.fr", 
      "full_name": "Olea Romacho, Mar\u00eda", 
      "given_names": "Mar\u00eda"
    }, 
    {
      "affiliations": [
        {
          "country": "Germany", 
          "value": "Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg, 22607, Germany", 
          "organization": "Deutsches Elektronen-Synchrotron DESY"
        }, 
        {
          "country": "Germany", 
          "value": "II. Institut f\u00fcr Theoretische Physik, Universit\u00e4t Hamburg, Luruper Chaussee 149, Hamburg, 22607, Germany", 
          "organization": "Universit\u00e4t Hamburg"
        }
      ], 
      "surname": "Weiglein", 
      "email": "georg.weiglein@desy.de", 
      "full_name": "Weiglein, Georg", 
      "given_names": "Georg"
    }
  ], 
  "titles": [
    {
      "source": "Springer", 
      "title": "First shot of the smoking gun: probing the electroweak phase transition in the 2HDM with novel searches for A \u2192 ZH in   <math> <msup> <mi>\u2113</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>\u2212</mo> </msup> <mi>t</mi> <mover> <mi>t</mi> <mo>\u00af</mo> </mover> </math>  $$ {\\ell}^{+}{\\ell}^{-}t\\overline{t} $$  and   <math> <mi>\u03bd\u03bdb</mi> <mover> <mi>b</mi> <mo>\u00af</mo> </mover> </math>  $$ \\nu \\nu b\\overline{b} $$  final states"
    }
  ], 
  "dois": [
    {
      "value": "10.1007/JHEP01(2024)107"
    }
  ], 
  "publication_info": [
    {
      "page_end": "44", 
      "journal_title": "Journal of High Energy Physics", 
      "material": "article", 
      "journal_volume": "2024", 
      "artid": "JHEP01(2024)107", 
      "year": 2024, 
      "page_start": "1", 
      "journal_issue": "1"
    }
  ], 
  "$schema": "http://repo.scoap3.org/schemas/hep.json", 
  "acquisition_source": {
    "date": "2024-04-25T00:31:18.371934", 
    "source": "Springer", 
    "method": "Springer", 
    "submission_number": "f33e3f60029a11ef81c58e7301cc4a06"
  }, 
  "page_nr": [
    44
  ], 
  "license": [
    {
      "url": "https://creativecommons.org/licenses//by/4.0", 
      "license": "CC-BY-4.0"
    }
  ], 
  "copyright": [
    {
      "holder": "The Author(s)", 
      "year": "2024"
    }
  ], 
  "control_number": "82882", 
  "record_creation_date": "2024-01-22T03:30:18.201074", 
  "_files": [
    {
      "checksum": "md5:ff2afaba2cbfc18f9740b88a6c63c877", 
      "filetype": "xml", 
      "bucket": "893814db-0d68-40b7-a6b4-040ae8cd21cf", 
      "version_id": "1ebd5e5a-7496-49c5-bf1f-ba4baacc821b", 
      "key": "10.1007/JHEP01(2024)107.xml", 
      "size": 22263
    }, 
    {
      "checksum": "md5:155b4049f0c326c0b14959e58b063f16", 
      "filetype": "pdf/a", 
      "bucket": "893814db-0d68-40b7-a6b4-040ae8cd21cf", 
      "version_id": "1f059592-674c-44cf-828e-246825d636f9", 
      "key": "10.1007/JHEP01(2024)107_a.pdf", 
      "size": 1912998
    }
  ], 
  "collections": [
    {
      "primary": "Journal of High Energy Physics"
    }
  ], 
  "arxiv_eprints": [
    {
      "categories": [
        "hep-ph"
      ], 
      "value": "2309.17431"
    }
  ], 
  "abstracts": [
    {
      "source": "Springer", 
      "value": "Recently the ATLAS collaboration has reported the first results of searches for heavy scalar resonances decaying into a Z boson and a lighter new scalar resonance, where the Z boson decays leptonically and the lighter scalar decays into a top-quark pair, giving rise to   <math> <msup> <mi>\u2113</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>\u2212</mo> </msup> <mi>t</mi> <mover> <mi>t</mi> <mo>\u00af</mo> </mover> </math>  $$ {\\ell}^{+}{\\ell}^{-}t\\overline{t} $$  final states. This had previously been identified as a smoking-gun signature at the LHC for a first-order electroweak phase transition (FOEWPT) within the framework of two Higgs doublet models (2HDMs). In addition, ATLAS also presented new limits where the Z boson decays into pairs of neutrinos and the lighter scalar resonance into bottom-quark pairs, giving rise to the   <math> <mi>\u03bd\u03bdb</mi> <mover> <mi>b</mi> <mo>\u00af</mo> </mover> </math>  $$ \\nu \\nu b\\overline{b} $$  final state. We analyze the impact of these new searches on the 2HDM parameter space, with emphasis on their capability to probe currently allowed 2HDM regions featuring a strong FOEWPT. We also study the complementarity of these new searches with other LHC probes that could target the FOEWPT region of the 2HDM. Remarkably, the ATLAS search in the   <math> <msup> <mi>\u2113</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>\u2212</mo> </msup> <mi>t</mi> <mover> <mi>t</mi> <mo>\u00af</mo> </mover> </math>  $$ {\\ell}^{+}{\\ell}^{-}t\\overline{t} $$  final state shows a local 2.85 \u03c3 excess (for masses of about 650 GeV and 450 GeV for the heavy and light resonance) in the 2HDM parameter region that would yield a FOEWPT in the early universe, which could constitute the first experimental hint of baryogenesis at the electroweak scale. We analyze the implications of this excess, and discuss the detectability prospects for the associated gravitational wave signal from the FOEWPT. Furthermore, we project the sensitivity reach of the   <math> <msup> <mi>\u2113</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>\u2212</mo> </msup> <mi>t</mi> <mover> <mi>t</mi> <mo>\u00af</mo> </mover> </math>  $$ {\\ell}^{+}{\\ell}^{-}t\\overline{t} $$  signature for the upcoming runs of the LHC. Finally, we introduce the python package thdmTools, a state-of-art tool for the exploration of the 2HDM."
    }
  ], 
  "imprints": [
    {
      "date": "2024-01-19", 
      "publisher": "Springer"
    }
  ]
}
Published on:
19 January 2024
Publisher:
Springer
Published in:
Journal of High Energy Physics , Volume 2024 (2024)
Issue 1
Pages 1-44
DOI:
https://doi.org/10.1007/JHEP01(2024)107
arXiv:
2309.17431
Copyrights:
The Author(s)
Licence:
CC-BY-4.0

Fulltext files: