ausblenden:
Schlagwörter:
-
Zusammenfassung:
The BL Lac type object AP Librae (z = 0.049) was detected at the 7 standard deviation level in
11h of live time observations with the High Energy Stereoscopic System (H.E.S.S.) in the summer
of 2010. The Fermi-LAT source 1FGL J1517.8-2423, associated with AP Librae, has a hard γ-
ray spectrum with a photon index of 2:1±0:1. No flux variability is detected in the H.E.S.S. data
set nor in 25 months of Fermi-LAT data. From the broad-band spectral-energy distribution AP
Librae has been classified as a low-frequency-peaked BL Lac. Archival and contemporaneous Xray
observations by the Swift and RXTE satellites show a hard energy spectrum which, together
with the flat Fermi-LAT spectrum and the H.E.S.S. detection at very-high energies (VHE, E ≥
100GeV), indicate an unusually broad high-energy component stretching from X-rays to VHE
γ-rays, wider than all other VHE γ-ray emitting LBL, making AP Librae a unique VHE emitter.
