Searches for lepton-flavour-violating decays of the Higgs boson into eτ and μτ in √s = 13 TeV pp collisions with the ATLAS detector

The ATLAS collaboration

doi:10.1007/JHEP07(2023)166

Searches for lepton-flavour-violating decays of the Higgs boson into eτ and μτ in √s = 13 TeV pp collisions with the ATLAS detector

The ATLAS collaboration

Research output: Contribution to journal › Article › peer-review

23 Citations (Scopus)

Abstract

This paper presents direct searches for lepton flavour violation in Higgs boson decays, H → eτ and H → μτ, performed using data collected with the ATLAS detector at the LHC. The searches are based on a data sample of proton-proton collisions at a centre-of-mass energy √s = 13 TeV, corresponding to an integrated luminosity of 138 fb^-1. Leptonic (τ → ℓν_ℓ ν_τ) and hadronic (τ → hadrons ν_τ) decays of the τ-lepton are considered. Two background estimation techniques are employed: the MC-template method, based on data-corrected simulation samples, and the Symmetry method, based on exploiting the symmetry between electrons and muons in the Standard Model backgrounds. No significant excess of events is observed and the results are interpreted as upper limits on lepton-flavour-violating branching ratios of the Higgs boson. The observed (expected) upper limits set on the branching ratios at 95% confidence level, B (H → eτ) < 0.20% (0.12%) and B (H → μτ) < 0.18% (0.09%), are obtained with the MC-template method from a simultaneous measurement of potential H → eτ and H → μτ signals. The best-fit branching ratio difference, B (H → μτ) → B (H → eτ), measured with the Symmetry method in the channel where the τ-lepton decays to leptons, is (0.25 ± 0.10)%, compatible with a value of zero within 2.5σ.

Original language	English
Article number	166
Pages (from-to)	1-73
Number of pages	74
Journal	Journal of High Energy Physics
Volume	2023
Issue number	7
DOIs	https://doi.org/10.1007/JHEP07(2023)166
Publication status	Published - Jul 2023
Externally published	Yes

Bibliographical note

Copyright the Author(s). Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.

Keywords

Hadron-Hadron Scattering

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10.1007/JHEP07(2023)166Licence: CC BY

Publisher version (open access)Final published version, 2.79 MBLicence: CC BY

Cite this

@article{30df7ad590644ba8bc7b1cfbbff014db,

title = "Searches for lepton-flavour-violating decays of the Higgs boson into eτ and μτ in √s = 13 TeV pp collisions with the ATLAS detector",

abstract = "This paper presents direct searches for lepton flavour violation in Higgs boson decays, H → eτ and H → μτ, performed using data collected with the ATLAS detector at the LHC. The searches are based on a data sample of proton-proton collisions at a centre-of-mass energy √s = 13 TeV, corresponding to an integrated luminosity of 138 fb-1. Leptonic (τ → ℓνℓ ντ) and hadronic (τ → hadrons ντ) decays of the τ-lepton are considered. Two background estimation techniques are employed: the MC-template method, based on data-corrected simulation samples, and the Symmetry method, based on exploiting the symmetry between electrons and muons in the Standard Model backgrounds. No significant excess of events is observed and the results are interpreted as upper limits on lepton-flavour-violating branching ratios of the Higgs boson. The observed (expected) upper limits set on the branching ratios at 95% confidence level, B (H → eτ) < 0.20% (0.12%) and B (H → μτ) < 0.18% (0.09%), are obtained with the MC-template method from a simultaneous measurement of potential H → eτ and H → μτ signals. The best-fit branching ratio difference, B (H → μτ) → B (H → eτ), measured with the Symmetry method in the channel where the τ-lepton decays to leptons, is (0.25 ± 0.10)%, compatible with a value of zero within 2.5σ. ",

keywords = "Hadron-Hadron Scattering",

author = "{The ATLAS collaboration} and G. Aad and B. Abbott and Abbott, {D. C.} and K. Abeling and Abidi, {S. H.} and A. Aboulhorma and H. Abramowicz and H. Abreu and Y. Abulaiti and {Abusleme Hoffman}, {A. C.} and Acharya, {B. S.} and {Adam Bourdarios}, C. and L. Adamczyk and L. Adamek and Addepalli, {S. V.} and J. Adelman and A. Adiguzel and S. Adorni and T. Adye and Affolder, {A. A.} and Y. Afik and Agaras, {M. N.} and J. Agarwala and A. Aggarwal and C. Agheorghiesei and Aguilar-Saavedra, {J. A.} and A. Ahmad and F. Ahmadov and Ahmed, {W. S.} and S. Ahuja and X. Ai and G. Aielli and {Ait Tamlihat}, M. and B. Aitbenchikh and I. Aizenberg and M. Akbiyik and {\AA}kesson, {T. P.A.} and Akimov, {A. V.} and {Al Khoury}, K. and Alberghi, {G. L.} and J. Albert and P. Albicocco and S. Alderweireldt and M. Aleksa and Aleksandrov, {I. N.} and C. Alexa and T. Alexopoulos and A. Alfonsi and F. Alfonsi and M. Alhroob and B. Ali and S. Ali and M. Aliev and G. Alimonti and W. Alkakhi and C. Allaire and Allbrooke, {B. M.M.} and {Allendes Flores}, {C. A.} and Allport, {P. P.} and A. Aloisio and F. Alonso and C. Alpigiani and {Alvarez Estevez}, M. and {Alvarez Fernandez}, A. and Alviggi, {M. G.} and M. Aly and {Amaral Coutinho}, Y. and A. Ambler and C. Amelung and M. Amerl and Ames, {C. G.} and D. Amidei and {Amor Dos Santos}, {S. P.} and Amos, {K. R.} and V. Ananiev and C. Anastopoulos and T. Andeen and Anders, {J. K.} and Andrean, {S. Y.} and A. Andreazza and S. Angelidakis and A. Angerami and Anisenkov, {A. V.} and A. Annovi and C. Antel and Anthony, {M. T.} and E. Antipov and M. Antonelli and Antrim, {D. J.A.} and F. Anulli and M. Aoki and T. Aoki and {Aparisi Pozo}, {J. A.} and Aparo, {M. A.} and {Aperio Bella}, L. and C. Appelt and N. Aranzabal and {Araujo Ferraz}, V. and C. Arcangeletti and Arce, {A. T.H.} and E. Arena and Arguin, {J. F.} and S. Argyropoulos and Arling, {J. H.} and Armbruster, {A. J.} and O. Arnaez and H. Arnold and {Arrubarrena Tame}, {Z. P.} and G. Artoni and H. Asada and K. Asai and S. Asai and Asbah, {N. A.} and J. Assahsah and K. Assamagan and R. Astalos and Atkin, {R. J.} and M. Atkinson and Atlay, {N. B.} and H. Atmani and Atmasiddha, {P. A.} and K. Augsten and S. Auricchio and Auriol, {A. D.} and Austrup, {V. A.} and G. Avner and G. Avolio and K. Axiotis and G. Azuelos and D. Babal and H. Bachacou and K. Bachas and A. Bachiu and F. Backman and A. Badea and P. Bagnaia and M. Bahmani and Bailey, {A. J.} and Bailey, {V. R.} and Baines, {J. T.} and C. Bakalis and Baker, {O. K.} and Bakker, {P. J.} and E. Bakos and {Bakshi Gupta}, D. and S. Balaji and R. Balasubramanian and Baldin, {E. M.} and P. Balek and E. Ballabene and F. Balli and Baltes, {L. M.} and Balunas, {W. K.} and J. Balz and E. Banas and M. Bandieramonte and A. Bandyopadhyay and S. Bansal and L. Barak and Barberio, {E. L.} and D. Barberis and M. Barbero and G. Barbour and Barends, {K. N.} and T. Barillari and Barisits, {M. S.} and T. Barklow and Barnett, {R. M.} and P. Baron and {Baron Moreno}, {D. A.} and A. Baroncelli and G. Barone and Barr, {A. J.} and {Barranco Navarro}, L. and F. Barreiro and {Barreiro Guimar{\~a}es da Costa}, J. and U. Barron and {Barros Teixeira}, {M. G.} and S. Barsov and F. Bartels and R. Bartoldus and Barton, {A. E.} and P. Bartos and A. Basalaev and A. Basan and M. Baselga and I. Bashta and A. Bassalat and Basso, {M. J.} and Basson, {C. R.} and Bates, {R. L.} and S. Batlamous and Batley, {J. R.} and B. Batool and M. Battaglia and D. Battulga and M. Bauce and P. Bauer and Beacham, {J. B.} and T. Beau and Beauchemin, {P. H.} and F. Becherer and P. Bechtle and Beck, {H. P.} and K. Becker and Beddall, {A. J.} and Bednyakov, {V. A.} and Bee, {C. P.} and Beemster, {L. J.} and Beermann, {T. A.} and M. Begalli and M. Begel and A. Behera and Behr, {J. K.} and {Beirao Da Cruz E Silva}, C. and Beirer, {J. F.} and F. Beisiegel and M. Belfkir and G. Bella and L. Bellagamba and A. Bellerive and P. Bellos and K. Beloborodov and K. Belotskiy and Belyaev, {N. L.} and D. Benchekroun and F. Bendebba and Y. Benhammou and Benjamin, {D. P.} and M. Benoit and Bensinger, {J. R.} and S. Bentvelsen and L. Beresford and M. Beretta and {Bergeaas Kuutmann}, E. and N. Berger and B. Bergmann and J. Beringer and S. Berlendis and G. Bernardi and C. Bernius and Bernlochner, {F. U.} and T. Berry and P. Berta and A. Berthold and Bertram, {I. A.} and S. Bethke and A. Betti and Bevan, {A. J.} and J. Shojaii",

note = "Copyright the Author(s). Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.",

year = "2023",

month = jul,

doi = "10.1007/JHEP07(2023)166",

language = "English",

volume = "2023",

pages = "1--73",

journal = "Journal of High Energy Physics",

issn = "1029-8479",

publisher = "Springer, Springer Nature",

number = "7",

}

TY - JOUR

T1 - Searches for lepton-flavour-violating decays of the Higgs boson into eτ and μτ in √s = 13 TeV pp collisions with the ATLAS detector

AU - The ATLAS collaboration

AU - Aad, G.

AU - Abbott, B.

AU - Abbott, D. C.

AU - Abeling, K.

AU - Abidi, S. H.

AU - Aboulhorma, A.

AU - Abramowicz, H.

AU - Abreu, H.

AU - Abulaiti, Y.

AU - Abusleme Hoffman, A. C.

AU - Acharya, B. S.

AU - Adam Bourdarios, C.

AU - Adamczyk, L.

AU - Adamek, L.

AU - Addepalli, S. V.

AU - Adelman, J.

AU - Adiguzel, A.

AU - Adorni, S.

AU - Adye, T.

AU - Affolder, A. A.

AU - Afik, Y.

AU - Agaras, M. N.

AU - Agarwala, J.

AU - Aggarwal, A.

AU - Agheorghiesei, C.

AU - Aguilar-Saavedra, J. A.

AU - Ahmad, A.

AU - Ahmadov, F.

AU - Ahmed, W. S.

AU - Ahuja, S.

AU - Ai, X.

AU - Aielli, G.

AU - Ait Tamlihat, M.

AU - Aitbenchikh, B.

AU - Aizenberg, I.

AU - Akbiyik, M.

AU - Åkesson, T. P.A.

AU - Akimov, A. V.

AU - Al Khoury, K.

AU - Alberghi, G. L.

AU - Albert, J.

AU - Albicocco, P.

AU - Alderweireldt, S.

AU - Aleksa, M.

AU - Aleksandrov, I. N.

AU - Alexa, C.

AU - Alexopoulos, T.

AU - Alfonsi, A.

AU - Alfonsi, F.

AU - Alhroob, M.

AU - Ali, B.

AU - Ali, S.

AU - Aliev, M.

AU - Alimonti, G.

AU - Alkakhi, W.

AU - Allaire, C.

AU - Allbrooke, B. M.M.

AU - Allendes Flores, C. A.

AU - Allport, P. P.

AU - Aloisio, A.

AU - Alonso, F.

AU - Alpigiani, C.

AU - Alvarez Estevez, M.

AU - Alvarez Fernandez, A.

AU - Alviggi, M. G.

AU - Aly, M.

AU - Amaral Coutinho, Y.

AU - Ambler, A.

AU - Amelung, C.

AU - Amerl, M.

AU - Ames, C. G.

AU - Amidei, D.

AU - Amor Dos Santos, S. P.

AU - Amos, K. R.

AU - Ananiev, V.

AU - Anastopoulos, C.

AU - Andeen, T.

AU - Anders, J. K.

AU - Andrean, S. Y.

AU - Andreazza, A.

AU - Angelidakis, S.

AU - Angerami, A.

AU - Anisenkov, A. V.

AU - Annovi, A.

AU - Antel, C.

AU - Anthony, M. T.

AU - Antipov, E.

AU - Antonelli, M.

AU - Antrim, D. J.A.

AU - Anulli, F.

AU - Aoki, M.

AU - Aoki, T.

AU - Aparisi Pozo, J. A.

AU - Aparo, M. A.

AU - Aperio Bella, L.

AU - Appelt, C.

AU - Aranzabal, N.

AU - Araujo Ferraz, V.

AU - Arcangeletti, C.

AU - Arce, A. T.H.

AU - Arena, E.

AU - Arguin, J. F.

AU - Argyropoulos, S.

AU - Arling, J. H.

AU - Armbruster, A. J.

AU - Arnaez, O.

AU - Arnold, H.

AU - Arrubarrena Tame, Z. P.

AU - Artoni, G.

AU - Asada, H.

AU - Asai, K.

AU - Asai, S.

AU - Asbah, N. A.

AU - Assahsah, J.

AU - Assamagan, K.

AU - Astalos, R.

AU - Atkin, R. J.

AU - Atkinson, M.

AU - Atlay, N. B.

AU - Atmani, H.

AU - Atmasiddha, P. A.

AU - Augsten, K.

AU - Auricchio, S.

AU - Auriol, A. D.

AU - Austrup, V. A.

AU - Avner, G.

AU - Avolio, G.

AU - Axiotis, K.

AU - Azuelos, G.

AU - Babal, D.

AU - Bachacou, H.

AU - Bachas, K.

AU - Bachiu, A.

AU - Backman, F.

AU - Badea, A.

AU - Bagnaia, P.

AU - Bahmani, M.

AU - Bailey, A. J.

AU - Bailey, V. R.

AU - Baines, J. T.

AU - Bakalis, C.

AU - Baker, O. K.

AU - Bakker, P. J.

AU - Bakos, E.

AU - Bakshi Gupta, D.

AU - Balaji, S.

AU - Balasubramanian, R.

AU - Baldin, E. M.

AU - Balek, P.

AU - Ballabene, E.

AU - Balli, F.

AU - Baltes, L. M.

AU - Balunas, W. K.

AU - Balz, J.

AU - Banas, E.

AU - Bandieramonte, M.

AU - Bandyopadhyay, A.

AU - Bansal, S.

AU - Barak, L.

AU - Barberio, E. L.

AU - Barberis, D.

AU - Barbero, M.

AU - Barbour, G.

AU - Barends, K. N.

AU - Barillari, T.

AU - Barisits, M. S.

AU - Barklow, T.

AU - Barnett, R. M.

AU - Baron, P.

AU - Baron Moreno, D. A.

AU - Baroncelli, A.

AU - Barone, G.

AU - Barr, A. J.

AU - Barranco Navarro, L.

AU - Barreiro, F.

AU - Barreiro Guimarães da Costa, J.

AU - Barron, U.

AU - Barros Teixeira, M. G.

AU - Barsov, S.

AU - Bartels, F.

AU - Bartoldus, R.

AU - Barton, A. E.

AU - Bartos, P.

AU - Basalaev, A.

AU - Basan, A.

AU - Baselga, M.

AU - Bashta, I.

AU - Bassalat, A.

AU - Basso, M. J.

AU - Basson, C. R.

AU - Bates, R. L.

AU - Batlamous, S.

AU - Batley, J. R.

AU - Batool, B.

AU - Battaglia, M.

AU - Battulga, D.

AU - Bauce, M.

AU - Bauer, P.

AU - Beacham, J. B.

AU - Beau, T.

AU - Beauchemin, P. H.

AU - Becherer, F.

AU - Bechtle, P.

AU - Beck, H. P.

AU - Becker, K.

AU - Beddall, A. J.

AU - Bednyakov, V. A.

AU - Bee, C. P.

AU - Beemster, L. J.

AU - Beermann, T. A.

AU - Begalli, M.

AU - Begel, M.

AU - Behera, A.

AU - Behr, J. K.

AU - Beirao Da Cruz E Silva, C.

AU - Beirer, J. F.

AU - Beisiegel, F.

AU - Belfkir, M.

AU - Bella, G.

AU - Bellagamba, L.

AU - Bellerive, A.

AU - Bellos, P.

AU - Beloborodov, K.

AU - Belotskiy, K.

AU - Belyaev, N. L.

AU - Benchekroun, D.

AU - Bendebba, F.

AU - Benhammou, Y.

AU - Benjamin, D. P.

AU - Benoit, M.

AU - Bensinger, J. R.

AU - Bentvelsen, S.

AU - Beresford, L.

AU - Beretta, M.

AU - Bergeaas Kuutmann, E.

AU - Berger, N.

AU - Bergmann, B.

AU - Beringer, J.

AU - Berlendis, S.

AU - Bernardi, G.

AU - Bernius, C.

AU - Bernlochner, F. U.

AU - Berry, T.

AU - Berta, P.

AU - Berthold, A.

AU - Bertram, I. A.

AU - Bethke, S.

AU - Betti, A.

AU - Bevan, A. J.

AU - Shojaii, J.

N1 - Copyright the Author(s). Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.

PY - 2023/7

Y1 - 2023/7

N2 - This paper presents direct searches for lepton flavour violation in Higgs boson decays, H → eτ and H → μτ, performed using data collected with the ATLAS detector at the LHC. The searches are based on a data sample of proton-proton collisions at a centre-of-mass energy √s = 13 TeV, corresponding to an integrated luminosity of 138 fb-1. Leptonic (τ → ℓνℓ ντ) and hadronic (τ → hadrons ντ) decays of the τ-lepton are considered. Two background estimation techniques are employed: the MC-template method, based on data-corrected simulation samples, and the Symmetry method, based on exploiting the symmetry between electrons and muons in the Standard Model backgrounds. No significant excess of events is observed and the results are interpreted as upper limits on lepton-flavour-violating branching ratios of the Higgs boson. The observed (expected) upper limits set on the branching ratios at 95% confidence level, B (H → eτ) < 0.20% (0.12%) and B (H → μτ) < 0.18% (0.09%), are obtained with the MC-template method from a simultaneous measurement of potential H → eτ and H → μτ signals. The best-fit branching ratio difference, B (H → μτ) → B (H → eτ), measured with the Symmetry method in the channel where the τ-lepton decays to leptons, is (0.25 ± 0.10)%, compatible with a value of zero within 2.5σ.

AB - This paper presents direct searches for lepton flavour violation in Higgs boson decays, H → eτ and H → μτ, performed using data collected with the ATLAS detector at the LHC. The searches are based on a data sample of proton-proton collisions at a centre-of-mass energy √s = 13 TeV, corresponding to an integrated luminosity of 138 fb-1. Leptonic (τ → ℓνℓ ντ) and hadronic (τ → hadrons ντ) decays of the τ-lepton are considered. Two background estimation techniques are employed: the MC-template method, based on data-corrected simulation samples, and the Symmetry method, based on exploiting the symmetry between electrons and muons in the Standard Model backgrounds. No significant excess of events is observed and the results are interpreted as upper limits on lepton-flavour-violating branching ratios of the Higgs boson. The observed (expected) upper limits set on the branching ratios at 95% confidence level, B (H → eτ) < 0.20% (0.12%) and B (H → μτ) < 0.18% (0.09%), are obtained with the MC-template method from a simultaneous measurement of potential H → eτ and H → μτ signals. The best-fit branching ratio difference, B (H → μτ) → B (H → eτ), measured with the Symmetry method in the channel where the τ-lepton decays to leptons, is (0.25 ± 0.10)%, compatible with a value of zero within 2.5σ.

KW - Hadron-Hadron Scattering

UR - http://www.scopus.com/inward/record.url?scp=85165876369&partnerID=8YFLogxK

U2 - 10.1007/JHEP07(2023)166

DO - 10.1007/JHEP07(2023)166

M3 - Article

AN - SCOPUS:85165876369

SN - 1029-8479

VL - 2023

SP - 1

EP - 73

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

IS - 7

M1 - 166

ER -

Searches for lepton-flavour-violating decays of the Higgs boson into eτ and μτ in √s = 13 TeV pp collisions with the ATLAS detector

Abstract

Bibliographical note

Keywords

Access to Document

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Cite this