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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

The cross section of 12 C+ 12 C fusion reactions determines the conditions of carbon ignition in stars. The presence of structures, which are likely to extend to low energies, makes the extrapolation of data collected at high energy to the stellar energy difficult and potentially inaccurate, so a direct measurement is desirable. Here we report on an extremely improbable two-step background process which prohibits the measurement of the 12 C(12 C,p) 23 Na carbon fusion reaction at low energies in the presence of deuterium contamination. It appears that with a modified setup and selected targets reliable measurements down to E cm =2.0 MeV are possible.. 11th Symposium on Nuclei in the Cosmos-NIC XI

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