In this Letter we report the discovery of TeV gamma-ray emission from a supernova remnant made with the CANGAROO 3.8 m telescope. TeV gamma rays were detected at the sky position and extension coincident with the northeast rim of shell-type supernova remnant (SNR) SN 1006 (Type Ia). SN 1006 has been a most likely candidate for an extended TeV gamma-ray source, since the clear synchrotron X-ray emission from the rims was recently observed by ASCA (Koyama et al.), which is strong evidence for the existence of very high energy (up to hundreds of TeV) electrons in the SNR. The observed TeV gamma-ray flux was (2.4 ‫ע‬ 0.0.7 [systematic]) # 10 3.0 ‫ע‬ 0.9 (4.6 ‫ע‬ 0.6 ‫ע‬ 1.4) # 10 1.7 ‫ע‬ 0.5 from the 1996 and 1997 observations, respectively. Also, we set an upper limit on the TeV gamma-ray emission from the southwest rim, which is estimated to be cm Ϫ2 s Ϫ1 (≥ TeV, 95% confidence level) Ϫ12

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We have observed the Vela pulsar region at TeV energies using the 3.8 m imaging Cherenkov telescope near Woomera, South Australia between January 1993 and March 1995. Evidence of an unpulsed gamma-ray signal has been detected at the 5.8 sigma level. The detected gamma-ray flux is (2.9 +/- 0.5 +/- 0.4) x 10^-12 photons cm^-2 sec^-1 above 2.5 +/- 1.0 TeV and the signal is consistent with steady emission over the two years. The gamma-ray emission region is offset from the Vela pulsar position to the southeast by about 0.13 deg. No pulsed emission modulated with the pulsar period has been detected and the 95 % confidence flux upper limit to the pulsed emission from the pulsar is (3.7 +/- 0.7) x 10^-13 photons cm^-2 sec^-1 above 2.5 +/- 1.0 TeV.Comment: 18 pages, 3 figures, LaTeX with AASTeX, accepted for publication in ApJ Letter

A new imaging atmospheric Cherenkov telescope with a light-weight re ector has been constructed. Light, robust, and durable mirror facets of containing CFRP (Carbon Fiber Reinforced Plastic) laminates were developed for the telescope. The re ector has a parabolic shape (f/1.1) with a 30 m 2 surface area which consists of sixty spherical mirror facets. The image size of each mirror facet is 0 .08 (FWHM) on average. The attitude of each facet can be adjusted by stepping motors. After Preprint submitted to Elsevier Preprint 26 May 2 0 0 0 the rst in situ adjustment, a point image of about 0 .14 (FWHM) over 3 degree eld-of-view was obtained. The e ect of gravitational load on the optical system was con rmed to be negligible at the focal plane. The telescope has been in operation with an energy threshold for gamma-rays of < 300 GeV since May 1999.

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