TeV gamma-rays from supernova remnants Tycho's SNR, Cas A, Crab and Geminga

Tycho's SNR has been observed by SHALON imaging Cherenkov telescope at Tien-Shan (3340 m a.s.l.). This object, Ia SNR, has long been considered as a candidate to CR hadron source in the Northern Hemisphere. The expected pion decay gamma-flux Fγ ∼ E −1 γ extends up to > 30 TeV, whereas the IC gamma-ray flux has a cutoff above a few TeV. So, the detection of gamma-rays at energies of 10 - 80 TeV by SHALON is an evidence for hadron origin of the rays. The observation results on Cas A by SHALON are also presented. Its integral γ-ray flux at energies of > 0.8 TeV is found to be (0.68 ± 0.13) × 10 −12 cm −2 s −1 at energies of > 0.8 TeV. The TeV photon spectrum measured by SHALON can be described with a power-law with the index of kγ = −1.32 ± 0.18. The value Geminga flux obtained by SHALON is lower than the upper limits published before by other experiments. Its integral γ-ray flux is found to be (0.48 ± 0.10) × 10 −12 cm −2 s −1 at energies of > 0.8 TeV. Within the range 0.8 - 6 TeV, the integral energy spectrum is well described by the power law I( >E γ) ∝ E −0.59±0.10 γ . The energy spectrum of Geminga is harder than Crab spectrum. Crab Nebula has been regularly observed by high mountain SHALON telescope. The integral energy spectrum is well described by the power law I( >E γ) ∝ E −1.40±0.07 γ within the range 0.8 - 30 TeV. An image of γ-ray emission from Crab Nebula by SHALON telescope is presented. TeV γ-quantum spectrum is generated by photons, produced by relativistic electrons and positrons via Inverse Compton if the average magnetic field in the region of VHE γ-ray emission 67 nT, which is taken from the comparison of TeV and X-ray emission regions (Chandra).