SUMMARY OF PROPOSAL 42042
DR KEN EBISAWA
LHEA/USRA
MD USA 20771
GREENBELT
CODE 668, NASA/GSFC

  E-mail: EBISAWA@SUBARU.GSFC.NASA.GOV	Tel: 301-286-1586	Fax: 301-286-1684
  Medium: 4GBDAT

Subject: X-RAY BINARIES                                              
  Title: THE FIRST X-RAY SPECTROSCOPY OF THE SUPER SOFT SOURCE CAL87                     


Abstract:
 The discovery of numerous Super Soft Sources (SSS) by ROSAT has confirmed that SSS
 are a new, important category of astronomical objects. Their nature is unclear,
 mainly because spectral information obtained by ROSAT is very limited. In our recent
 ASCA observation of the SSS RXJ0925.7-4758, which is effectively the first X-ray
 spectroscopy of SSS, we clearly detected absorption edge structures from highly
 ionized heavy elements, indicating the emission is from hot and optically thick
 white dwarf or neutron star atmosphere. We propose to carry out a similar spectral
 study of CAL87, which is a prototype of SSS and the only other SSS observable with
 ASCA. The ASCA high resolution spectra will be crucial in modeling the X-ray emission from SSS.

 Co-Is:
   1  KOJI MUKAI          	LHEA/USRA, NASA/GSFC          USA       
      (No Co-I contact data)
   2  ALAN SMALE          	LHEA/USRA, NASA/GSFC          USA       
   3  NICHOLAS WHITE      	NASA/GSFC                     USA       
   4  JOHN HEISE          	SRON                          NETH      
   5  WOUTER HARTMANN     	SRON                          NETH      


Target Name           PRI RA        Dec        Time TC  Off GIS SIS_Cts  Obs
-------------------   --- --------  --------   ---- --  --- --- -------  ---
CAL87                  0   86.6875  -71.1481    80   N   Y   P  0.05000   1