Search for π0 decays to invisible particles
(2021) In Journal of High Energy Physics 2021(2).- 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... (More)
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.
(Less)
- author
- Cortina Gil, E. and Husek, T. LU
- author collaboration
- organization
- publishing date
- 2021-02
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Beyond Standard Model, Exotics, Fixed target experiments, Rare decay
- in
- Journal of High Energy Physics
- volume
- 2021
- issue
- 2
- article number
- 201
- publisher
- Springer
- external identifiers
-
- scopus:85101791870
- ISSN
- 1029-8479
- DOI
- 10.1007/JHEP02(2021)201
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2021, The Author(s).
- id
- 79994cf9-0029-4e17-bccf-83fd34634f90
- date added to LUP
- 2022-03-30 11:42:47
- date last changed
- 2024-04-12 02:21:59
@article{79994cf9-0029-4e17-bccf-83fd34634f90, abstract = {{<p>The NA62 experiment at the CERN SPS reports a study of a sample of 4 × 10<sup>9</sup> tagged π<sup>0</sup> mesons from K<sup>+</sup> → π<sup>+</sup>π<sup>0</sup>(γ), searching for the decay of the π<sup>0</sup> to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of 4.4 × 10<sup>−9</sup> 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<sup>+</sup> → π<sup>+</sup>X, where X is a particle escaping detection with mass in the range 0.110–0.155 GeV/c<sup>2</sup> 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.</p>}}, author = {{Cortina Gil, E. and Husek, T.}}, issn = {{1029-8479}}, keywords = {{Beyond Standard Model; Exotics; Fixed target experiments; Rare decay}}, language = {{eng}}, number = {{2}}, publisher = {{Springer}}, series = {{Journal of High Energy Physics}}, title = {{Search for π<sup>0</sup> decays to invisible particles}}, url = {{http://dx.doi.org/10.1007/JHEP02(2021)201}}, doi = {{10.1007/JHEP02(2021)201}}, volume = {{2021}}, year = {{2021}}, }