Search for a feebly interacting particle X in the decay K %2b → π %2b X Article uri icon

abstract

  • A search for the K%2b → π%2bX decay, where X is a long-lived feebly interacting particle, is performed through an interpretation of the K%2b → π%2bνν¯ analysis of data collected in 2017 by the NA62 experiment at CERN. Two ranges of X masses, 0–110 MeV/c2 and 154–260 MeV/c2, and lifetimes above 100 ps are considered. The limits set on the branching ratio, BR(K%2b → π%2bX), 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. © 2021, The Author(s).

authors

publication date

  • 2021-01-01