Direkt zum InhaltDirekt zur SucheDirekt zur Navigation
▼ Zielgruppen ▼

Humboldt-Universität zu Berlin - Mathematisch-Naturwissen­schaft­liche Fakultät - Experimentelle Elementarteilchenphysik

The H Collaboration (2007)

Multi-wavelength Observations of PG 1553+113 with HESS

ArXiv e-prints.

Very high energy (VHE; >100 GeV) gamma-ray observations of PG 1553+113 were made with the High Energy Stereoscopic System (HESS) in 2005 and 2006. A strong signal, 10 standard deviations, is detected by HESS during the 2 years of observations (24.8 hours live time). The time-averaged energy spectrum, measured between 225 GeV to 1.3 TeV, is characterized by a very steep power law (photon index of Gamma = (4.5 +- 0.3 stat +- 0.1 syst). The integral flux above 300 GeV is 3.4% of the Crab Nebula flux and shows no evidence for any variations, on any time scale. H+K (1.45-2.45 micron) spectroscopy of PG 1553+113 was performed in March 2006 with SINFONI, an integral field spectrometer of the ESO Very Large Telescope (VLT) in Chile. The redshift of PG 1553+113 is still unknown, as no absorption or emission lines were found.

Provided by the SAO/NASA Astrophysics Data System