X‐ray observations of SN1987A with Ginga

Continuous observations of the Large Magellanic CLoud region made with Ginga since February 25, 1987 revealed the X‐rays with unusual energy spectrum from the region of 0.2×0.3 deg2 including the supernova SN1987A. The first detection of a significant X‐ray flux from SN1987A was detected about 130 days after its explosion. The energy spectrum shows the presence of unusually hard component above 10–15 keV. The light curve shows the relatively large intensity variations in the low energy band of 5.8–16.1 keV, in contrast to small variations in high energy band of 16.1–27.8 keV. About 320 days after the explosion, the SN1987A showed large increase about factor of 6 in 20 days, and they decayed to the half of the peak flux level in 30 days.