Explaining the extended GeV gamma-ray emission adjacent to HESS J1825-137
Abstract
HESS J1825-137 is one of the most powerful and luminous TeV gamma-ray pulsar wind nebulae (PWN). To the south of HESS J1825-137, Fermi-LAT observation revealed a new region of GeV gamma-ray emission with three apparent peaks (termed here, GeV-ABC). This study presents interstellar medium (ISM) data and spectral energy distribution (SED) modelling towards the GeV emission to understand the underlying particle acceleration. We considered several particle accelerator scenarios - the PWN associated with HESS J1825-137, the progenitor SNR also associated with HESS J1825-137, plus the gamma-ray binary system LS 5039. It was found that the progenitor SNR of HESS J1825-137 has insufficient energetics to account for all GeV emission. GeV-ABC may be a reflection of an earlier epoch in the history of the PWN associated with HESS 1825-137, assuming fast diffusion perhaps including advection. LS 5039 cannot meet the required energetics to be the source of particle acceleration. A combination of HESS J1825-137 and LS 5039 could be plausible sources.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- June 2021
- DOI:
- 10.1093/mnras/stab983
- arXiv:
- arXiv:2104.05953
- Bibcode:
- 2021MNRAS.504.1840C
- Keywords:
-
- ISM: clouds;
- cosmic rays;
- ISM: individual (HESS J1825-137);
- ISM: individual (LS 5039);
- ISM: supernova remnants;
- gamma rays: ISM;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- Submitted to MNRAS: https://academic.oup.com/mnras/advance-article-abstract/doi/10.1093/mnras/stab983/6219862