26-30 October 2015
Asia/Tokyo timezone

Gamma-ray emission from the recently discovered dwarf galaxy Reticulum II

27 Oct 2015, 17:38
Room 2 ()

Room 2

Oral presentation Dark matter searches (direct and indirect) Dark Matter


Prof. Savvas Koushiappas (Brown University)


I will present results on the analysis of gamma-ray emission from the recently discovered dwarf galaxy Reticulum II. Using Fermi-LAT data and a suite of background models we quantify the probability that the observed gamma-ray emission is due to background. Taking into account trials factors, we find emission p-values in the range between 9.8x10^-5 and 9.7x10^-3 and conclude that Reticulum II has the most significant gamma-ray emission from any other known dwarf galaxy. I will also discuss the dark matter content of Reticulum II as derived from kinematic studies of its member stellar population and show that Reticulum II has a dark matter halo similar to other nearby dwarf galaxies. If the gamma ray emission is due to dark matter annihilation, the annihilation cross section is consistent with the s-wave relic abundance cross section. I will conclude by discussing further tests that are needed in order to ascertain the likelihood of this emission to be due to a conventional astrophysical interpretation.

Primary author

Prof. Savvas Koushiappas (Brown University)

Presentation Materials