Search for Line-like and Box-shaped Spectral Features from Nearby Galaxy Clusters with 11.4 Years of Fermi Large Area Telescope Data

ABSTRACT Galaxy clusters are the largest virialized objects in the Universe and, as such, have high dark matter (DM) concentrations. This abundance of dark matter makes them promising targets for indirect DM searches. Here we report the details of a search, utilizing almost 12 yr of Fermi/LAT data, for gamma-ray signatures from the pair annihilation of WIMP dark matter in the GeV energy band. From this, we present the constraints on the annihilation cross-section for the $b\overline{b}$, W+W−, and γγ channels, derived from the non-detection of a characteristic signal from five nearby, high Galactic latitude, galaxy clusters (Centaurus, Coma, Virgo, Perseus, and Fornax). We discuss the potential of a boost to the signal due to the presence of substructures in the DM haloes of selected objects, as well as the impact of uncertainties in DM profiles on the presented results. We assert that the obtained limits are, within a small factor, comparable to the best available limits of those based on Fermi/LAT observations of dwarf spheroidal galaxies.

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A PHOTOMETRIC STUDY ON THE FORMATION OF THE EARLY TYPE GALAXIES IN NEARBY GALAXY CLUSTERS

Journal of The Korean Astronomical Society ◽

10.5303/jkas.2005.38.2.145 ◽

2005 ◽

Vol 38 (2) ◽

pp. 145-148 ◽

Cited By ~ 2

Author(s):

TAEHYUN KIM ◽

MYUNG GYOON LEE

Keyword(s):

Galaxy Clusters ◽

Nearby Galaxy ◽

Photometric Study ◽

Early Type

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A fast radio burst in the direction of the Virgo Cluster

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2574 ◽

2019 ◽

Vol 490 (1) ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Devansh Agarwal ◽

Duncan R Lorimer ◽

Anastasia Fialkov ◽

Keith W Bannister ◽

Ryan M Shannon ◽

...

Keyword(s):

Galaxy Clusters ◽

Confidence Limit ◽

Luminosity Function ◽

High Sensitivity ◽

Virgo Cluster ◽

Dispersion Measure ◽

Nearby Galaxy ◽

The Mean ◽

Fast Radio Burst

ABSTRACT The rate of fast radio bursts (FRBs) in the direction of nearby galaxy clusters is expected to be higher than the mean cosmological rate if intrinsically faint FRBs are numerous. In this paper, we describe a targeted search for faint FRBs near the core of the Virgo Cluster using the Australian Square Kilometre Array Pathfinder telescope. During 300 h of observations, we discovered one burst, FRB 180417, with dispersion measure (DM) = 474.8 cm−3 pc. The FRB was promptly followed up by several radio telescopes for 27 h, but no repeat bursts were detected. An optical follow-up of FRB 180417 using the PROMPT5 telescope revealed no new sources down to an R-band magnitude of 20.1. We argue that FRB 180417 is likely behind the Virgo Cluster as the Galactic and intracluster DM contribution are small compared to the DM of the FRB, and there are no galaxies in the line of sight. The non-detection of FRBs from Virgo constrains the faint-end slope, α < 1.52 (at 68 per cent confidence limit), and the minimum luminosity, Lmin ≳ 2 × 1040 erg s−1 (at 68 per cent confidence limit), of the FRB luminosity function assuming cosmic FRB rate of 104 FRBs per sky per day with flux above 1 Jy located out to redshift of 1. Further FRB surveys of galaxy clusters with high-sensitivity instruments will tighten the constraints on the faint end of the luminosity function and, thus, are strongly encouraged.

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