Searches for gamma rays above 100 TeV from SN 1987A and above 50 TeV from Cen X-3 were carried out with an air shower array at Mount Chacaltaya over a period of 3 years. The array, which consists of 13 4 m2 and 28 1 m2 scintillation detectors, was located on a slope of about 30° facing southward to effectively observe air showers coming from the directions of these sources. In the analysis, a selection by shower age parameter was applied to reduce the background due to showers initiated by protons or nuclei. No significant excess of gamma rays (and/or neutral particles) from these sources was found; our upper limits on the flux of gamma rays above 100 TeV from SN 1987A and above 50 TeV from Cen X-3 are 2.2 × 10-13 and 3.5 × 10-13 photons cm-2 s-1 (95% confidence level), respectively.
- Gamma rays: observations
- Stars: individual (Centaurus X-3)
- Supernovae: Individual(SN 1987A)