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تسجيل مستخدم جديدInterstellar gas towards the TeV gamma-ray sources HESS J1640-465 and HESS J1641-463
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We present a detailed analysis of the interstellar medium towards the TeV $gamma$-ray sources HESS J1640$-$465 and HESS J1641$-$463 using results from the Mopra Southern Galactic Plane CO Survey and from a Mopra 7 mm-wavelength study. The $gamma$-ray sources are positionally coincident with two supernova remnants G338.3$-$0.0 and G338.5+0.1 respectively. A bright complex of HII regions connect the two SNRs and TeV objects. Observations in the CO(1-0) transition lines reveal substantial amounts of diffuse gas positionally coincident with the $gamma$-ray sources at multiple velocities along the line of sight, while 7 mm observations in CS, SiO, HC$_{3}$N and CH$_{3}$OH transition lines reveal regions of dense, shocked gas. Archival HI data from the Southern Galactic Plane Survey was used to account for the diffuse atomic gas. Physical parameters of the gas towards the TeV sources were calculated from the data. We find that for a hadronic origin for the $gamma$-ray emission, the cosmic-ray enhancement rates are $sim 10^{3}$ and $10^{2}$ times the local solar value for HESS J1640$-$465 and HESS J1641$-$463 respectively.
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The bright TeV source HESS J1640-465 is positionally coincident with the young SNR G338.3-0.0, and the nearby HESS J1641-463 with TeV gamma-ray emission seems to be closely associated with it. Based on the nonlinear diffusion shock acceleration (NLDS
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There are only few very-high-energy sources in our Galaxy which might accelerate particles up to the knee of the cosmic-ray spectrum. To understand the mechanisms of particle acceleration in these PeVatron candidates, textit{Fermi}-LAT and H.E.S.S. o
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