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We report on the X-ray observation of the radio selected supernova SN1979C carried out with ASCA in December 1997. The supernova of type II$_{L}$ was first observed in the optical and occurred in the weakly barred, almost face on spiral galaxy NGC 4321 (M100) which is at a distance of 17.1 Mpc, and contains at least three other supernovae discovered in this century. No point source was detected at the radio position of SN1979C in a 3 diameter half power response circle in a 27.3 ks SIS exposure. The background and galaxy subtracted SN signal had a 3$sigma$ upper limit to the count rate of 1.2$times 10^{-3}$ cps in the full ASCA SIS band (0.4-10.0 keV). These measurements give the first ever x-ray flux limit of a Type II$_{L}$ SN in the higher energy band ($geq$ 2 keV) which is an important diagnostic of the {it outgoing} shock wave ploughing through the circumstellar medium.
We have observed a radio-quiet QSO Kaz 102 (z=0.136) with ASCA as a part of our program of complete spectral characterization of hard X-ray selected AGNs. We found that Kaz 102 shows unusual spectral properties. A simple power-law with absorption in
We report the results from an ASCA X-ray observation of the powerful Broad Line Radio Galaxy, 3C109. The ASCA spectra confirm our earlier ROSAT detection of intrinsic X-ray absorption associated with the source. The absorbing material obscures a cent
We have obtained a moderately long (100 kilosecond) ASCA observation of the Seyfert 1 galaxy Markarian 231, the most luminous of the local ultraluminous infrared galaxy (ULIRG) population. In the best-fitting model we do not see the X-ray source dire
We present the analysis of the X-ray data of the young active star HD35850 obtained with ASCA and ROSAT. Our main goal was to see if there is a difference in the elemental abundances of active stars between young and more evolved objects. A two tempe
SN 2005kd is among the most luminous supernovae (SNe) to be discovered at X-ray wavelengths. We have re-analysed all good angular resolution (better than $20$ FWHM PSF) archival X-ray data for SN 2005kd. The data reveal an X-ray light curve that decr