New dark matter analysis of Milky Way dwarf satellite galaxies with MADHATv2

We obtain bounds on dark matter annihilation using 14 years of publiclyavailable Fermi-LAT data from a set of 54 dwarf spheroidal galaxies, usingspectral information from 16 energy bins. We perform this analysis using ourupdated and publicly available code MADHATv2, which can be used to test avariety of models for dark matter particle physics and astrophysics in anaccessible manner. In particular, we note that including Carina III in theanalysis strengthens constraints on $s$-wave annihilation into two-bodyStandard Model final states by a factor of $\sim 3$ but broadens the error onthe constraint due to the large uncertainty of its $J$-factor. Our findingsillustrate the importance of verifying if Carina III is in fact a dwarfspheroidal galaxy and measuring more precisely its $J$-factor. More generally,they highlight the significance of forthcoming discoveries of nearbyultra-faint dwarfs for dark matter indirect detection.