Constraining extended gamma-ray emission from galaxy clusters

	Constraining extended gamma-ray emission from galaxy clusters
	Han, Jiaxin 1,2,3; Frenk, Carlos S.3; Eke, Vincent R.3; Gao, Liang 3,4; White, Simon D. M.5; Boyarsky, Alexey 6,7; Malyshev, Denys 7; Ruchayskiy, Oleg 8
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2012-12-01
卷号	427 期号:2 页码:1651-1665
关键词	astroparticle physics galaxies: clusters: individual: Coma Cosmology: observations dark matter gamma-rays: galaxies: clusters Virgo Fornax
英文摘要	Cold dark matter models predict the existence of a large number of substructures within dark matter haloes. If the cold dark matter consists of weakly interacting massive particles, their annihilation within these substructures could lead to diffuse GeV emission that would dominate the annihilation signal of the host halo. In this work we search for GeV emission from three nearby galaxy clusters: Coma, Virgo and Fornax. We first remove known extragalactic and galactic diffuse gamma-ray backgrounds and point sources from the Fermi 2-yr catalogue and find a significant residual diffuse emission in all three clusters. We then investigate whether this emission is due to (i) unresolved point sources, (ii) dark matter annihilation or (iii) cosmic rays (CR). Using 45 months of Fermi-Large Area Telescope (Fermi-LAT) data we detect several new point sources (not present in the Fermi 2-yr point source catalogue) which contaminate the signal previously analysed by Han et al. Including these and accounting for the effects of undetected point sources, we find no significant detection of extended emission from the three clusters studied. Instead, we determine upper limits on emission due to dark matter annihilation and CR. For Fornax and Virgo, the limits on CR emission are consistent with theoretical models, but for Coma the upper limit is a factor of 2 below the theoretical expectation. Allowing for systematic uncertainties associated with the treatment of CR, the upper limits on the cross-section for dark matter annihilation from our clusters are more stringent than those from analyses of dwarf galaxies in the Milky Way. Adopting a boost factor of similar to 10(3) from subhaloes on cluster luminosity as suggested by recent theoretical models, we rule out the thermal cross-section for supersymmetric dark matter particles for masses as large as 100 GeV (depending on the annihilation channel).
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	SUPERSYMMETRIC DARK-MATTER ; VIRGO CLUSTER ; GALACTIC-CENTER ; TELESCOPE ; MASS ; HALO ; ANNIHILATION ; INFALL
收录类别	SCI
语种	英语
WOS记录号	WOS:000311413500062
内容类型	期刊论文
源URL	[http://119.78.226.72/handle/331011/18155]
专题	上海天文台_星系宇宙学重点实验室
作者单位	1.Shanghai Astron Observ, Key Lab Res Galaxies & Cosmol, Shanghai 200030, Peoples R China 2.Chinese Acad Sci, Grad Sch, Beijing 100049, Peoples R China 3.Univ Durham, Sci Labs, Dept Phys, Inst Computat Cosmol, Durham DH1 3LE, England 4.Chinese Acad Sci, Natl Astron Observ, Partner Grp, Max Planck Inst Astrophys, Beijing 100012, Peoples R China 5.Max Planck Inst Astrophys, D-85748 Garching, Germany 6.Leiden Univ, Inst Lorentz Theoret Phys, Leiden, Netherlands 7.Bogolyubov Inst Theoret Phys, Kiev, Ukraine 8.CERN Phys Dept, Div Theory, CH-1211 Geneva, Switzerland
推荐引用方式 GB/T 7714	Han, Jiaxin,Frenk, Carlos S.,Eke, Vincent R.,et al. Constraining extended gamma-ray emission from galaxy clusters[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2012,427(2):1651-1665.
APA	Han, Jiaxin.,Frenk, Carlos S..,Eke, Vincent R..,Gao, Liang.,White, Simon D. M..,...&Ruchayskiy, Oleg.(2012).Constraining extended gamma-ray emission from galaxy clusters.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,427(2),1651-1665.
MLA	Han, Jiaxin,et al."Constraining extended gamma-ray emission from galaxy clusters".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 427.2(2012):1651-1665.