8553( 4) - 12/29/99 10:29 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8553 Version: 4 Check-in Date: 29-Dec-1999 10:28:35 1.Proposal Title: A Bright X-ray Transient in M31 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO/DD 8 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Michael Garcia Harvard-Smithsonian Center for Astrophysics CoI: Stephen S. Murray Chandra X-ray Center, SAO N CoI: Francis Primini Smithsonian Astrophysical Observatory N CoI: Jeffrey E. McClintock Smithsonian Astrophysical Observatory N ------------------------------------------------------------------------------------ 5. Abstract We have recently discovered a bright x-ray transient in M31 (IAUC 7291, Murray, Garcia, and Primini), which based on its x-ray luminosity and position near the core of M31 is very likely the first X-ray Nova (XRN) discovered outside the Milky Way (MW). We propose to observe this transient with the HST WFPC2 in order to search for a UV and optical counterpart, and to measure its optical decay rate. Discovery of a counterpart is both very possible (based on scaling MW XRN to M31) and would help euclidate the nature of this transient. ------------------------------------------------------------------------------------ Observations Description ------------------------ This should be a straightfoward set of U and V images using the PC mode of the WFPC2, aimed 6.5 arc-sec to the west of the core of M31 Real Time Justification ----------------------- The observations are being done to search for an x-ray transient found near the core of M31, and so must be done within a few weeks - the transient will fade on this timescale, so if the delay is subtantially longer the chance of finding the transient will decrease. Calibration Justification ------------------------- No special calibration is needed Additional Comments ------------------- We request the the PI be notified when an approximate date for the observations has been set, and as soon as the data is available. ------------------------------------------------------------------------------------ 8553( 4) - 12/29/99 10:29 - [ 2] Data Distribution Paper Products: YES Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 8553( 4) - 12/29/99 10:29 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 CXOJ004242.2 EXT-STAR, X-RAY RA=00H 42M 42.93S +/- .05S, J2000 V = 24.0+/-1 +411608 TRANSIENT DEC=41D 16' 10.49" +/- 0.01D 8553( 4) - 12/29/99 10:29 - [ 4] Visit: 01 Visit Priority: Visit Requirements: ORIENT 55D TO 60D BETWEEN 20-Jan-2000 AND 01-Mar-2000 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 CXOJ004242. WFPC2 IMAGE PC1 F336W CR-SPLIT=NO 3 500 S 2+411608 ------------------------------------------------------------------------------------------------------------------------------------ 30 CXOJ004242. WFPC2 IMAGE PC1 F555W 5 500 S 2+411608 ------------------------------------------------------------------------------------------------------------------------------------ 8553( 4) - 12/29/99 10:29 - [ 5] Summary Form for Proposal 8553 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO/DD ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 55D TO 60D BETWEEN 20-Jan-2000 AND 01-Mar-2000 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F336W F555W ------------------------------------------------------------------------------------------------------------------------------------ Target Names CXOJ004242.2+411608 ------------------------------------------------------------------------------------------------------------------------------------