Discovery of very-high-energy gamma-ray emission from the vicinity of PSR J1913+1011 with HESS

Abstract

The HESS experiment, an array of four Imaging Atmospheric Cherenkov Telescopes with high sensitivity and large field-of-view, has been used to search for emitters of very-high-energy (VHE, >100 GeV) $\gamma$-rays along the Galactic plane, covering the region 30° $<\, l\, <$ 60°, 280° $<\, l\, <$ 330°, and -3° $<\, b\, <$ 3°. In this continuation of the HESS Galactic Plane Scan, a new extended VHE $\gamma$-ray source was discovered at $\alpha_{2000}$=19$^{\rm h}$12$^{\rm m}$49$^{\rm s}$, $\delta_{2000}$=+10°09´06´´(HESS J1912+101). Its integral flux between 1-10 TeV is ~10% of the Crab Nebula flux in the same energy range. The measured energy spectrum can be described by a power law d $N/{\rm d}E \, \sim \, E^{-\Gamma}$ with a photon index $\Gamma = 2.7 \pm 0.2_{\mbox{stat}}\pm 0.3_{\mbox{sys}}$. HESS J1912+101 is plausibly associated with the high spin-down luminosity pulsar PSR J1913+1011. We also discuss associations with an as yet unconfirmed SNR candidate proposed from low frequency radio observation and/or with molecular clouds found in 13CO data