FERMI -LAT OBSERVATIONS AND A BROADBAND STUDY OF SUPERNOVA REMNANT CTB 109
Author(s)
Castro, Daniel; Slane, Patrick; Ellison, Donald C.; Patnaude, Daniel J.
DownloadCastro-2012-Fermi-LAT observatio.pdf (947.4Kb)
PUBLISHER_POLICY
Publisher Policy
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Terms of use
Metadata
Show full item recordAbstract
CTB 109 (G109.1-1.0) is a Galactic supernova remnant (SNR) with a hemispherical shell morphology in X-rays and in the radio band. In this work, we report the detection of γ-ray emission coincident with CTB 109, using 37 months of data from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. We study the broadband characteristics of the remnant using a model that includes hydrodynamics, efficient cosmic-ray (CR) acceleration, nonthermal emission, and a self-consistent calculation of the X-ray thermal emission. We find that the observations can be successfully fit with two distinct parameter sets, one where the γ-ray emission is produced primarily by leptons accelerated at the SNR forward shock and the other where γ-rays produced by forward shock accelerated CR ions dominate the high-energy emission. Consideration of thermal X-ray emission introduces a novel element to the broadband fitting process, and while it does not rule out either the leptonic or the hadronic scenarios, it constrains the parameter sets required by the model to fit the observations. Moreover, the model that best fits the thermal and nonthermal emission observations is an intermediate case, where both radiation from accelerated electrons and hadrons contribute almost equally to the γ-ray flux observed.
Date issued
2012-08Department
MIT Kavli Institute for Astrophysics and Space ResearchJournal
Astrophysical Journal
Publisher
IOP Publishing
Citation
Castro, Daniel, Patrick Slane, Donald C. Ellison, and Daniel J. Patnaude. “ FERMI -LAT OBSERVATIONS AND A BROADBAND STUDY OF SUPERNOVA REMNANT CTB 109 .” The Astrophysical Journal 756, no. 1 (August 20, 2012): 88. © 2012 The American Astronomical Society
Version: Final published version
ISSN
0004-637X
1538-4357