Search for a feebly interacting particle X in the decay K+ -> pi X+



Gil, E Cortina, Kleimenova, A, Minucci, E, Padolski, S, Petrov, P, Shaikhiev, A, Volpe, R, Numao, T, Velghe, B, Bryman, D
et al (show 190 more authors) (2021) Search for a feebly interacting particle X in the decay K+ -> pi X+. JOURNAL OF HIGH ENERGY PHYSICS, 2021 (3).

Access the full-text of this item by clicking on the Open Access link.

Abstract

<jats:title>A<jats:sc>bstract</jats:sc> </jats:title><jats:p>A search for the <jats:italic>K</jats:italic><jats:sup>+</jats:sup> → <jats:italic>π</jats:italic><jats:sup>+</jats:sup><jats:italic>X</jats:italic> decay, where <jats:italic>X</jats:italic> is a long-lived feebly interacting particle, is performed through an interpretation of the <jats:italic>K</jats:italic><jats:sup>+</jats:sup> → <jats:inline-formula><jats:alternatives><jats:tex-math>$$ {\pi}^{+}\nu \overline{\nu} $$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>π</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mi>ν</mml:mi> <mml:mover> <mml:mi>ν</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math></jats:alternatives></jats:inline-formula> analysis of data collected in 2017 by the NA62 experiment at CERN. Two ranges of <jats:italic>X</jats:italic> masses, 0–110 MeV<jats:italic>/c</jats:italic><jats:sup>2</jats:sup> and 154–260 MeV<jats:italic>/c</jats:italic><jats:sup>2</jats:sup>, and lifetimes above 100 ps are considered. The limits set on the branching ratio, BR(<jats:italic>K</jats:italic><jats:sup>+</jats:sup> → <jats:italic>π</jats:italic><jats:sup>+</jats:sup><jats:italic>X</jats:italic>), are competitive with previously reported searches in the first mass range, and improve on current limits in the second mass range by more than an order of magnitude.</jats:p>

Item Type: Article
Uncontrolled Keywords: Beyond Standard Model, Exotics, Fixed target experiments
Divisions: Faculty of Science and Engineering > School of Physical Sciences
Depositing User: Symplectic Admin
Date Deposited: 16 Nov 2021 08:44
Last Modified: 18 Jan 2023 21:24
DOI: 10.1007/JHEP03(2021)058
Open Access URL: https://link.springer.com/content/pdf/10.1007/JHEP...
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3143205