Decaying dark matter: the case for a deep X-ray observation of Draco

Lovell, M.R.; Bertone, G.; Boyarsky, A.; Jenkins, A.; Ruchayskiy, O.

doi:10.1093/mnras/stv963

Decaying dark matter: the case for a deep X-ray observation of Draco

Lovell, M.R.; Bertone, G.; Boyarsky, A.; Jenkins, A.; Ruchayskiy, O.

Authors

M.R. Lovell

G. Bertone

A. Boyarsky

Professor Adrian Jenkins a.r.jenkins@durham.ac.uk
Professor

O. Ruchayskiy

Abstract

Recent studies of M31, the Galactic Centre (GC), and galaxy clusters have made tentative detections of an X-ray line at ∼3.5 keV that could be produced by decaying dark matter. We use high-resolution simulations of the Aquarius project to predict the likely amplitude of the X-ray decay flux observed in the GC relative to that observed in M31, and also of the GC relative to other parts of the Milky Way halo and to dwarf spheroidal galaxies. We show that the reported detections from M31 and the GC are compatible with each other, and with upper limits arising from high galactic latitude observations, and imply a decay time τ ∼ 1028 s. We argue that this interpretation can be tested with deep observations of dwarf spheroidal galaxies: in 95 per cent of our mock observations, a 1.3 Ms pointed observation of Draco with XMM–Newton will enable us to discover or rule out at the 3σ level an X-ray feature from dark matter decay at 3.5 keV, for decay times τ < 0.8 × 1028 s.

Citation

Lovell, M., Bertone, G., Boyarsky, A., Jenkins, A., & Ruchayskiy, O. (2015). Decaying dark matter: the case for a deep X-ray observation of Draco. Monthly Notices of the Royal Astronomical Society, 451(2), 1573-1585. https://doi.org/10.1093/mnras/stv963

Journal Article Type	Article
Acceptance Date	Apr 29, 2015
Publication Date	Aug 1, 2015
Deposit Date	Feb 11, 2016
Publicly Available Date	Feb 16, 2016
Journal	Monthly Notices of the Royal Astronomical Society
Print ISSN	0035-8711
Electronic ISSN	1365-2966
Publisher	Royal Astronomical Society
Peer Reviewed	Peer Reviewed
Volume	451
Issue	2
Pages	1573-1585
DOI	https://doi.org/10.1093/mnras/stv963
Keywords	Dark matter.

Files

Published Journal Article (2.5 Mb)
PDF

Copyright Statement
This article has been accepted for publication in Monthly notices of the Royal Astronomical Society ©: 2015 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.