Speaker
Dr
Ekrem Oguzhan Angüner
(CPPM)
Description
HESS J1826$-$130 is an unidentified very-high-energy (VHE, E>0.1 TeV) gamma-ray source discovered by H.E.S.S. along the Galactic plane. The analysis of 215-hour H.E.S.S. data has revealed a steady TeV source with an extension of 0.21°. The source spectrum can be well described with a power-law function, showing a very hard spectral index of $\Gamma$ = 1.8 and an exponential cut-off at ~15 TeV. The apparent VHE emission of the source is strongly contaminated by the tails of the bright VHE emission from HESS J1825$-$137. Assuming a hadronic scenario and taking into account the properties of dense gas regions coincident with the best fit position of the source, investigation of the HESS J1826$-$130 spectrum suggests that the astrophysical object producing the observed VHE emission must be capable of accelerating the parental particle population close to PeV (10$^{15}$ eV) energies. In such a scenario this source would be a representative of population of PeV accelerators active in the Galaxy. A leptonic scenario, where electrons accelerated by the pulsar PSR J1826$-$1256 are up-scattering cosmic microwave background or infra-red photons, can also explain the VHE emission. In this case, HESS J1826$-$130 could be an example of a distinctive pulsar wind nebulae population, showing hard spectra and high cut-off energies.
Primary authors
Mr
Alexander Ziegler
(FAU)
Dr
Ekrem Oguzhan Angüner
(CPPM)
Dr
Igor Oya
(DESY)
Dr
Pol Bordas
(MPIK)
Dr
Sabrina Casanova
(MPIK, IFJ PAN)