Cookies

We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.


Durham Research Online
You are in:

γ-ray observations of extraterrestrial neutrino track events.

Brown, Anthony M. and Adams, Jenni and Chadwick, Paula M. (2015) 'γ-ray observations of extraterrestrial neutrino track events.', Monthly notices of the Royal Astronomical Society., 451 (1). pp. 323-331.

Abstract

In this paper we report the results of a γ-ray study of IceCube's extraterrestrial neutrino candidates detected as track-like events. Using 70 months of Fermi-Large Area Telescope (LAT) observations, a likelihood analysis of all 1–300 GeV photons within 5° of the track-like neutrino candidates’ origin was undertaken, to search for spatially coincident γ-ray emission. One of IceCube's HESE (High Energy Starting Event) track events was found to be spatially coincident with a γ-ray bright active galactic nucleus (AGN), PKS 0723-008. We find however that the chance probability for Fermi-LAT detected AGN to be spatially coincident with a single HESE track-like event is high (∼37 per cent). We therefore find no evidence of γ-ray emission associated with the detection of IceCube's HESE track-like neutrino candidates. Upper limits were calculated in the energy range of 1–300 GeV, assuming a point source origin for the neutrino events considered. The implications for the non-detection of γ-ray emission from the source of the HESE track-like events are briefly discussed. The large time period analysed in our study did however reveal two new γ-ray point sources. With a flux of (1.28 ± 0.08) × 10−9 photons cm−2 s−1, in the 1–300 GeV energy range, and an associated TS value of 220.6, one of these new point sources is positionally coincident with the AGN PKS 1346-112. The other point source has a 1–300 GeV flux of (7.95 ± 1.23) × 10−10 photons cm−2 s−1 and an associated TS value of 92.4. This new point source is spatially coincident with the radio source NVSS J072534 + 021645 suggesting that it too is an AGN.

Item Type:Article
Keywords:Neutrinos, Galaxies: active, Gamma rays: galaxies, Gamma-rays: general.
Full text:(VoR) Version of Record
Download PDF
(2922Kb)
Status:Peer-reviewed
Publisher Web site:http://dx.doi.org/10.1093/mnras/stv899
Publisher 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.
Date accepted:21 April 2015
Date deposited:29 June 2015
Date of first online publication:July 2015
Date first made open access:No date available

Save or Share this output

Export:
Export
Look up in GoogleScholar