ROSAT Status Report #92

[REQUEST@rosat.gsfc.nasa.gov]

		ROSAT Status Report#92
		   April 25nd 1994


Correction to the PSPC Off-Axis PSF memo
________________________________________

Please note that the PSPC off-axis psf memo (cal_ros_93_015) contains 
2 errors. In equation 7, the term (4r_b/r_scatt)^2 should be deleted;
in equation 15 the denominator should contain G_sigma, not r_sigma.

A corrected version of the memo is now available on 
/rosat/doc/pspc/off_axis_psf/cal_ros_93_015/

We apologize for any confusion this may have caused.

Note: The fortran subroutine available on /rosat/software/fortran/
off_axis_psf/ and the ftools derived from that do not contain this error. 

Thanks to Bob Rutledge and Vinay Kashyap for reporting the errors.


Informal Study Note
____________________

A brief memo is now available on /rosat/doc/pspc/spectral_calib/
cal_ros_94_005/    reminding investigators to use caution in defining 
their PSPC spectral extraction cell to avoid "ghost imaging" 
enhancement or suppression of the soft counts (below channel 20 
in 256 channel spectra).  This memo is a response to questions received at 
GSFC from the community.