!  +====================+
!  | PED OUTPUT PRODUCT |
!  +====================+
!
!  /tmp_mnt/cerb/u1/golombek/proposals/6809.prop
!  Generated by PREPROCESSOR, version 6.0e
!  Date: Wed Jan 31 11:39:00 EST 1996

Proposal_Information
              Title: An Optical Counterpart to the X-Ray Point Source in the Puppis A Supernova Remnant?
  Proposal_Category: GO
Scientific_Category: HOT STARS
              Cycle: 6


Investigators

            PI_Name: P. Frank Winkler
     PI_Institution: Middlebury College


           CoI_Name: Robert Petre
    CoI_Institution: Goddard Space Flight Center
            Contact: 

           CoI_Name: Chris M. Becker
    CoI_Institution: Massachusetts Institute of Technology
            Contact: 

           CoI_Name: Dale A. Frail
    CoI_Institution: National Radio Astronomy Observatory -- Very Large Array
            Contact: 


Abstract:
Recent  ROSAT observations of the supernova remnant Puppis A
have identified an X-ray point source near its center.  No X-
ray or radio pulsations have been detected from this source,
though the present limits are not stringent. All the data are
consistent with the source being a hot neutron star formed at
the time of the supernova which produced Puppis A, some 4000
years ago.  We propose to search for an optical counterpart to
the X-ray source, using the power of  HST and the WFPC2 to
reach significantly deeper than can be achieved from the
ground.  If the hot neutron star interpretation is correct, we
would expect it to be well beyond the limits of detectability
even from  HST.\ \  But the limits achievable from  HST should
enable us to rule out virtually all known alternative compact
sources on the basis of an unreasonably high X-ray/optical
flux ratio.


Questions


    Observing_Description:
We propose to observe the source with one of the WFC chips
for one full orbit in each of two filters:  F606W (Wide  V)
provides the best match with the chip response and should
give the highest sensitivity for all but the most highly
reddened sources (or intrinsically very red objects).  For a
source in Puppis A itself, for which E(B-V) ~ 0.5, this
filter should give the best sensitivity.  F814W (Wide  I)
will have a higher sensitivity for very highly reddened
sources, such as  a background extragalactic object, and will
give color information to help classify any object bright
enough to be detected through both filters.  These
observations should give a 3Sigma\\ detection for any source
with f_opt/f_X >~ 10^-5\\ in either  V or  I band, an increase
in sensitivity by a factor of 20 or more over the existing
ground-based data. Observations through each filter will be
done in 3 exposures of ~800\\ s each, in order to eliminate
almost entirely the chance of cosmic-ray contamination while
maintaining sky-limited conditions.

  Real_Time_Justification:
None.

Calibration_Justification:
None.

      Additional_Comments:



Fixed_Targets

  Target_Number: 1
    Target_Name: STAR-082158-430016
Alternate_Names: PUP-A-CENTRAL-SOURCE
    Description: STAR,NEUTRON STAR,SUPERNOVA,ISM,SNR
       Position: RA=08H 21M 57.50S +/- 0.5S,DEC=-43D 00' 15.8" +/- 5"
        Equinox: 2000.
        RV_or_Z: 
          RA_PM: 
         Dec_PM: 
          Epoch: 
Annual_Parallax: 
           Flux: 
                V = 24.+/-1.
       Comments: FLUX IS UPPER LIMIT ONLY.


Visits

      Visit_Number: 01
Visit_Requirements: ORIENT 60D TO 90D
   !             SCHED 30%
                SCHED 40%
  On_Hold_Comments: 
    Visit_Comments: Orientation to avoid bright stars

     Exposure_Number: 10
         Target_Name: STAR-082158-430016
              Config: WFPC2
              Opmode: IMAGE
            Aperture: WF3
          Sp_Element: F814W
          Wavelength: 
 Optional_Parameters: DITHER-TYPE=LINE 
Number_of_Iterations: 1
   Time_Per_Exposure: 1000S
Special_Requirements: 
            Comments: Pair-Dither-Pair.

     Exposure_Number: 20
         Target_Name: STAR-082158-430016
              Config: WFPC2
              Opmode: IMAGE
            Aperture: WF3
          Sp_Element: F606W
          Wavelength: 
 Optional_Parameters: DITHER-TYPE=LINE 
Number_of_Iterations: 1
   Time_Per_Exposure: 1100S
Special_Requirements: 
            Comments: Pair-Dither-Pair

Data_Distribution         ! Defaults indicated; change if desired

         Medium: 8MM
Blocking_Factor: 10
        Ship_To: PI_Address*P. Frank Winkler*Department of Physics*Middlebury College*Middlebury, VT*05753
       Ship_Via: UPS
Recipient_Email: 

! Let us know what you think of this template and software!
! Please send a list of your likes and dislikes to your Program Coordinator