DISCOVERY OF X-RAY EMISSION FROM THE GALACTIC SUPERNOVA REMNANT G32.8-0.1 WITHSUZAKU

Aya Bamba, Yukikatsu Terada, John Hewitt, Robert Petre, Lorella Angelini, Samar Safi-Harb, Ping Zhou, Fabrizio Bocchino, Makoto Sawada
2016 Astrophysical Journal  
We present the first dedicated X-ray study of the supernova remnant (SNR) G32.8-0.1 (Kes 78) with Suzaku. X-ray emission from the whole SNR shell has been detected for the first time. The X-ray morphology is well correlated with the emission from the radio shell, while anti-correlated with the molecular cloud found in the SNR field. The X-ray spectrum shows not only conventional low-temperature (kT 0.6 keV) thermal emission in a non-equilibrium ionization state, but also a very high temperature
more » ... (kT 3.4 keV) component with a very low ionization timescale ( 2.7e9 cm^-3s), or a hard non-thermal component with a photon index Gamma 2.3. The average density of the low-temperature plasma is rather low, of the order of 10^-3--10^-2 cm^-3, implying that this SNR is expanding into a low-density cavity. We discuss the X-ray emission of the SNR, also detected in TeV with H.E.S.S., together with multi-wavelength studies of the remnant and other gamma-ray emitting SNRs, such as W28 and RCW 86. Analysis of a time-variable source, 2XMM J185114.3-000004, found in the northern part of the SNR, is also reported for the first time. Rapid time variability and a heavily absorbed hard X-ray spectrum suggest that this source could be a new supergiant fast X-ray transient.
doi:10.3847/0004-637x/818/1/63 fatcat:pynoo3yab5eeve5rqzoy3paqo4