  We use MUSE spectroscopic observations of the dwarf spheroidal galaxy Leo T
between 470 and 935 nm to search for radiative decays of axion like particles
(ALPs). Under the assumption that ALPs constitute the dark matter component of
the Leo T halo, we derive bounds on the effective ALP-two-photon coupling. We
improve existing limits by more than one order of magnitude in the ALP mass
range 2.7-5.3 eV.
