Energy Dependent Morphology in the PWN Candidate HESSJ1825-137.

Funk, S. ; Hinton, J. A. ; DeJager, O. C.

Technical Information Center Oak Ridge Tennessee

关键词: Astrophysics;    Gamma rays;    Morphology;    Pulsars;    Observations;   

RP-ID  :  DE2007916980

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Observations with H.E.S.S. revealed a new source of very high-energy (VHE) gamma-rays above 100 GeV--HESS-J1825137--extending mainly to the south of the energetic pulsar PSRB1823-13. A detailed spectral and morphological analysis of HESS J1825137 reveals for the first time in VHE gamma-ray astronomy a steepening of the energy spectrum with increasing distance from the pulsar. This behaviour can be understood by invoking radiative cooling of the IC-Compton gamma-ray emitting electrons during their propagation. In this scenario the vastly different sizes between the VHE gamma-ray emitting region and the X-ray PWN associated with PSRB182313 can be naturally explained by different cooling timescales for the radiating electron populations. If this scenario is correct, HESS J1825137 can serve as a prototype for a whole class of asymmetric PWN in which the X-rays are extended over a much smaller angular scales than the gamma-rays and can help understanding recent detections of X-ray PWN in systems such as HESS J1640465 and HESS J1813178. The future GLAST satellite will probe lower electron energies shedding further light on cooling and diffusion processes in this source.