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Title: Demystifying an Unidentified EGRET Source by VHE gamma-ray Observations

Abstract

In a novel approach in observational high-energy gamma-ray astronomy, observations carried out by imaging atmospheric Cherenkov telescopes provide necessary templates to pinpoint the nature of intriguing, yet unidentified EGRET gamma-ray sources. Using GeV-photons detected by CGRO EGRET and taking advantage of high spatial resolution images from H.E.S.S. observations, we were able to shed new light on the EGRET observed gamma-ray emission in the Kookaburra complex, whose previous coverage in the literature is some-what contradictory. 3EGJ1420-6038 very likely accounts for two GeV gamma-ray sources (E>1 GeV), both in positional coincidence with the recently reported pulsar wind nebulae (PWN) by HESS in the Kookaburra/Rabbit complex. PWN associations at VHE energies, supported by accumulating evidence from observations in the radio and X-ray band, are indicative for the PSR/plerionic origin of spatially coincident, but still unidentified Galactic gamma-ray sources from EGRET. This not only supports the already suggested connection between variable, but unidentified low-latitude gamma-ray sources with pulsar wind nebulae (3EGJ1420-6038 has been suggested as PWN candidate previously), it also documents the ability of resolving apparently confused EGRET sources by connecting the GeV emission as measured from a large-aperture space-based gamma-ray instrument with narrow field-of-view but superior spatial resolution observations by ground-based atmospheric Cherenkovmore » telescopes, a very promising identification technique for achieving convincing individual source identifications in the era of GLAST-LAT.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
902496
Report Number(s):
SLAC-PUB-12464
astro-ph/0611653; TRN: US200717%%364
DOE Contract Number:
AC02-76SF00515
Resource Type:
Conference
Resource Relation:
Journal Name: Submitted to Astrophys.Space Sci.; Conference: To appear in the proceedings of The Multi-Messenger Approach to Unidentified Gamma-Ray Sources: 3rd Workshop on the Nature of Unidentified High-Energy Sources, Barcelona, Spain, 4-7 Jul 2006
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASTRONOMY; NEBULAE; ORIGIN; PULSARS; SPATIAL RESOLUTION; TELESCOPES; Astrophysics,ASTRO

Citation Formats

Reimer, Olaf, /Stanford U., HEPL /KIPAC, Menlo Park, Funk, Stefan, and /KIPAC, Menlo Park. Demystifying an Unidentified EGRET Source by VHE gamma-ray Observations. United States: N. p., 2007. Web.
Reimer, Olaf, /Stanford U., HEPL /KIPAC, Menlo Park, Funk, Stefan, & /KIPAC, Menlo Park. Demystifying an Unidentified EGRET Source by VHE gamma-ray Observations. United States.
Reimer, Olaf, /Stanford U., HEPL /KIPAC, Menlo Park, Funk, Stefan, and /KIPAC, Menlo Park. Tue . "Demystifying an Unidentified EGRET Source by VHE gamma-ray Observations". United States. doi:. https://www.osti.gov/servlets/purl/902496.
@article{osti_902496,
title = {Demystifying an Unidentified EGRET Source by VHE gamma-ray Observations},
author = {Reimer, Olaf and /Stanford U., HEPL /KIPAC, Menlo Park and Funk, Stefan and /KIPAC, Menlo Park},
abstractNote = {In a novel approach in observational high-energy gamma-ray astronomy, observations carried out by imaging atmospheric Cherenkov telescopes provide necessary templates to pinpoint the nature of intriguing, yet unidentified EGRET gamma-ray sources. Using GeV-photons detected by CGRO EGRET and taking advantage of high spatial resolution images from H.E.S.S. observations, we were able to shed new light on the EGRET observed gamma-ray emission in the Kookaburra complex, whose previous coverage in the literature is some-what contradictory. 3EGJ1420-6038 very likely accounts for two GeV gamma-ray sources (E>1 GeV), both in positional coincidence with the recently reported pulsar wind nebulae (PWN) by HESS in the Kookaburra/Rabbit complex. PWN associations at VHE energies, supported by accumulating evidence from observations in the radio and X-ray band, are indicative for the PSR/plerionic origin of spatially coincident, but still unidentified Galactic gamma-ray sources from EGRET. This not only supports the already suggested connection between variable, but unidentified low-latitude gamma-ray sources with pulsar wind nebulae (3EGJ1420-6038 has been suggested as PWN candidate previously), it also documents the ability of resolving apparently confused EGRET sources by connecting the GeV emission as measured from a large-aperture space-based gamma-ray instrument with narrow field-of-view but superior spatial resolution observations by ground-based atmospheric Cherenkov telescopes, a very promising identification technique for achieving convincing individual source identifications in the era of GLAST-LAT.},
doi = {},
journal = {Submitted to Astrophys.Space Sci.},
number = ,
volume = ,
place = {United States},
year = {Tue Apr 17 00:00:00 EDT 2007},
month = {Tue Apr 17 00:00:00 EDT 2007}
}

Conference:
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