Search for π0 decays to invisible particles

NA62 Collaboration

doi:10.1007/JHEP02(2021)201

Search for π⁰ decays to invisible particles

NA62 Collaboration

Physics and Astronomy

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

4 Citations (Scopus)

103 Downloads (Pure)

Abstract

The NA62 experiment at the CERN SPS reports a study of a sample of 4 × 10⁹tagged π⁰ mesons from K⁺ → π⁺π⁰(γ), searching for the decay of the π⁰ to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of 4.4 × 10⁻⁹ is set on the branching ratio at 90% confidence level, improving on previous results by a factor of 60. This result can also be interpreted as a model- independent upper limit on the branching ratio for the decay K⁺ → π⁺X, where X is a particle escaping detection with mass in the range 0.110–0.155 GeV/c² and rest lifetime greater than 100 ps. Model-dependent upper limits are obtained assuming X to be an axion-like particle with dominant fermion couplings or a dark scalar mixing with the Standard Model Higgs boson.

Original language	English
Article number	201
Number of pages	27
Journal	JHEP
Volume	2021
Issue number	2
DOIs	https://doi.org/10.1007/JHEP02(2021)201
Publication status	Published - 23 Feb 2021

Bibliographical note

Publisher Copyright:
© 2021, The Author(s).

Keywords

Beyond Standard Model
Exotics
Fixed target experiments
Rare decay

ASJC Scopus subject areas

Nuclear and High Energy Physics

Access to Document

10.1007/JHEP02(2021)201Licence: Creative Commons: Attribution (CC BY)

CortinaG2021SearchFinal published version, 695 KBLicence: Creative Commons: Attribution (CC BY)

Cite this

@article{f79933682502472f8ea75288784ed84a,

title = "Search for π0 decays to invisible particles",

abstract = "The NA62 experiment at the CERN SPS reports a study of a sample of 4 × 109 tagged π0 mesons from K+ → π+π0(γ), searching for the decay of the π0 to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of 4.4 × 10−9 is set on the branching ratio at 90% confidence level, improving on previous results by a factor of 60. This result can also be interpreted as a model- independent upper limit on the branching ratio for the decay K+ → π+X, where X is a particle escaping detection with mass in the range 0.110–0.155 GeV/c2 and rest lifetime greater than 100 ps. Model-dependent upper limits are obtained assuming X to be an axion-like particle with dominant fermion couplings or a dark scalar mixing with the Standard Model Higgs boson.",

keywords = "Beyond Standard Model, Exotics, Fixed target experiments, Rare decay",

author = "{NA62 Collaboration} and {Cortina Gil}, E. and A. Kleimenova and E. Minucci and S. Padolski and P. Petrov and A. Shaikhiev and R. Volpe and T. Numao and B. Velghe and D. Bryman and J. Fu and T. Husek and J. Jerhot and K. Kampf and M. Zamkovsky and R. Aliberti and G. Khoriauli and J. Kunze and D. Lomidze and R. Marchevski and L. Peruzzo and M. Vormstein and R. Wanke and P. Dalpiaz and M. Fiorini and I. Neri and A. Norton and F. Petrucci and H. Wahl and {Cotta Ramusino}, A. and A. Gianoli and E. Iacopini and G. Latino and M. Barbanera and T. Bache and Brunetti, {M. B.} and V. Duk and V. Fascianelli and Fry, {J. R.} and F. Gonnella and E. Goudzovski and L. Iacobuzio and C. Lazzeroni and N. Lurkin and F. Newson and C. Parkinson and A. Romano and A. Sergi and A. Sturgess and J. Swallow",

note = "Publisher Copyright: {\textcopyright} 2021, The Author(s).",

year = "2021",

month = feb,

day = "23",

doi = "10.1007/JHEP02(2021)201",

language = "English",

volume = "2021",

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TY - JOUR

T1 - Search for π0 decays to invisible particles

AU - NA62 Collaboration

AU - Cortina Gil, E.

AU - Kleimenova, A.

AU - Minucci, E.

AU - Padolski, S.

AU - Petrov, P.

AU - Shaikhiev, A.

AU - Volpe, R.

AU - Numao, T.

AU - Velghe, B.

AU - Bryman, D.

AU - Fu, J.

AU - Husek, T.

AU - Jerhot, J.

AU - Kampf, K.

AU - Zamkovsky, M.

AU - Aliberti, R.

AU - Khoriauli, G.

AU - Kunze, J.

AU - Lomidze, D.

AU - Marchevski, R.

AU - Peruzzo, L.

AU - Vormstein, M.

AU - Wanke, R.

AU - Dalpiaz, P.

AU - Fiorini, M.

AU - Neri, I.

AU - Norton, A.

AU - Petrucci, F.

AU - Wahl, H.

AU - Cotta Ramusino, A.

AU - Gianoli, A.

AU - Iacopini, E.

AU - Latino, G.

AU - Barbanera, M.

AU - Bache, T.

AU - Brunetti, M. B.

AU - Duk, V.

AU - Fascianelli, V.

AU - Fry, J. R.

AU - Gonnella, F.

AU - Goudzovski, E.

AU - Iacobuzio, L.

AU - Lazzeroni, C.

AU - Lurkin, N.

AU - Newson, F.

AU - Parkinson, C.

AU - Romano, A.

AU - Sergi, A.

AU - Sturgess, A.

AU - Swallow, J.

PY - 2021/2/23

Y1 - 2021/2/23

N2 - The NA62 experiment at the CERN SPS reports a study of a sample of 4 × 109 tagged π0 mesons from K+ → π+π0(γ), searching for the decay of the π0 to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of 4.4 × 10−9 is set on the branching ratio at 90% confidence level, improving on previous results by a factor of 60. This result can also be interpreted as a model- independent upper limit on the branching ratio for the decay K+ → π+X, where X is a particle escaping detection with mass in the range 0.110–0.155 GeV/c2 and rest lifetime greater than 100 ps. Model-dependent upper limits are obtained assuming X to be an axion-like particle with dominant fermion couplings or a dark scalar mixing with the Standard Model Higgs boson.

AB - The NA62 experiment at the CERN SPS reports a study of a sample of 4 × 109 tagged π0 mesons from K+ → π+π0(γ), searching for the decay of the π0 to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of 4.4 × 10−9 is set on the branching ratio at 90% confidence level, improving on previous results by a factor of 60. This result can also be interpreted as a model- independent upper limit on the branching ratio for the decay K+ → π+X, where X is a particle escaping detection with mass in the range 0.110–0.155 GeV/c2 and rest lifetime greater than 100 ps. Model-dependent upper limits are obtained assuming X to be an axion-like particle with dominant fermion couplings or a dark scalar mixing with the Standard Model Higgs boson.

KW - Beyond Standard Model

KW - Exotics

KW - Fixed target experiments

KW - Rare decay

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U2 - 10.1007/JHEP02(2021)201

DO - 10.1007/JHEP02(2021)201

M3 - Article

AN - SCOPUS:85101791870

SN - 1126-6708

VL - 2021

JO - JHEP

JF - JHEP

IS - 2

M1 - 201

ER -