pith. sign in

arxiv: 2406.01990 · v1 · pith:W2L6VC4Gnew · submitted 2024-06-04 · ✦ hep-ex · hep-ph

50 GeV π^- in, nothing out: a sensitive probe of invisible η and η' decays with NA64h

Yu. M. Andreev , A. Antonov , M. A. Ayala Torres , D. Banerjee , B. Banto Oberhauser , J. Bernhard , P. Bisio , A. Celentano
show 49 more authors
N. Charitonidis D. Cooke P. Crivelli E. Depero A. V. Dermenev S. V. Donskov R. R. Dusaev T. Enik V. N. Frolov S. V. Gertsenberger S. Girod S. N. Gninenko M. Hosgen V. A. Kachanov Y. Kambar A. E. Karneyeu G. D. Kekelidze B. Ketzer D. V. Kirpichnikov V. N. Kolosov V. A. Kramarenko L. V. Kravchuk N. V. Krasnikov S. V. Kuleshov V. E. Lyubovitskij A. Marini L. Marsicano V. A. Matveev R. Mena Fredes R. G. Mena Yanssen L. Molina Bueno M. Mongillo D. V. Peshekhonov V. A. Polyakov B. Radics K. M. Salamatin V. D. Samoylenko H. Sieber D. A. Shchukin O. Soto V. O. Tikhomirov I. V. Tlisova A. N. Toropin M. Tuzi P. V. Volkov V. Yu. Volkov I. V. Voronchikhin J. Zamora-Saa A. S. Zhevlakov
This is my paper
classification ✦ hep-ex hep-ph
keywords invisibledecaysdarkeventslimitmesonsna64hneutral
0
0 comments X
read the original abstract

We present the first results from a proof-of-concept search for dark sectors via invisible decays of pseudoscalar $\eta$ and $\eta'$ mesons in the NA64h experiment at the CERN SPS. Our novel technique uses the charge-exchange reaction of 50 GeV $\pi^-$ on nuclei of an active target as the source of neutral mesons. The $\eta, \eta' \to invisible$ events would exhibit themselves via a striking signature - the complete disappearance of the incoming beam energy in the detector. No evidence for such events has been found with $2.9\times10^{9}$ pions on target accumulated during one day of data taking. This allows us to set a stringent limit on the branching ratio ${\rm Br}(\eta' \to invisible) < 2.1 \times 10^{-4}$ improving the current bound by a factor of $\simeq3$. We also set a limit on ${\rm Br}(\eta \to invisible) < 1.1 \times 10^{-4}$ comparable with the existing one. These results demonstrate the great potential of our approach and provide clear guidance on how to enhance and extend the sensitivity for dark sector physics from future searches for invisible neutral meson decays.

This paper has not been read by Pith yet.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Irreducible Constraints on Hadronically Interacting Sub-GeV Dark Matter

    hep-ph 2025-12 unverdicted novelty 6.0

    Sub-GeV dark matter that interacts hadronically is ruled out for nucleon scattering cross sections above 10^{-36} cm² across the keV to 100 MeV mass range by combined cosmological and particle-decay constraints.