Southern Sky Survey with Cerenkov Telescope for High Energy Gamma-Rays

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We have detected 1,000 GeV(=1 TeV) gamma-rays from a pulsar PSR1706-44. The gamma-ray flux is - 10^<-11>cm^<-2>s^<-1>(> 1 TeV), with a statistical significance of 13 sigma. The pulsar PSR1706-44 is one of the five gamma-ray pulsars which have been found by satellite-borne experiments in the energy region of 100 MeV to 10 GeV. Our result is the first to detect 1,000 GeV gamma-rays from the pulsar PSR1706-44 among these five. This object is now the second very high energy gamma-ray source next the Crab, from which 1,000 GeV gamma-rays was detected with a statistical significance larger than 10 sigma.For the Crab pulsar/nebula, we obtained a flux of(7.6*1.0)X10^<-13>cm^<-2>s^<-1> at 7 TeV threshold of detected gamma-ray energy with a significance of 4 sigma. The Crab pulsar/nebula has been the only established object in the very high energy region at TeV. Large zenith angle observation we made from the southern hemisphere has an effect of increasing the threshold of detectable gamma-ray energy to about 7 TeV from 1 TeV at the zenith, however with a merit of a large detection area available. In the energy region of 1-10 TeV, our observation has, thus, a better sensitivity with a larger detection area at these energies than the others. The result contributes to establishing the Crab flux at TeV energies as a "standard" candle of gamma-ray source with which each telescope of imaging Cerenkov is to be calibrated.Observation of the Vela and PSR1055-52 pulsars were also made, and, combining the results on these four gamma-ray pulsars ; Crab, Vela, PSR1706-44 and PSR1055-52, we expect to obtain a better understanding of high energy processes which take place in these objects.Other types of objects such as an active galaxy PKS0521-365 and a binary radio pulsar PSR1259-63 were also observed for TeV gamma-ray emission.