8328( 5) - 08/25/99 09:37 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8328 Version: 5 Check-in Date: 25-Aug-1999 09:36:59 1.Proposal Title: HST ASTROMETRY TO GAUGE THE DISTANCE OF PSR0833-45 (VELA) and PSR0656+14 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 8 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Patrizia Caraveo Instituto di Fisica Cosmica, CNR CoI: Dr. Roberto Mignani ESA Space Telescope European Coordinating Y Facility CoI: Prof. Giovanni Bignami Agenzia Spaziale Italiana N ------------------------------------------------------------------------------------ 5. Abstract High angular resolution, coupled with sensitivity, makes HST the ideal instrument to measure tiny displacements of faint objects, such as those due to proper motions and annual parallaxes of Isolated Neutron Stars. In this proposal, we first include three exposures of the Vela pulsar aimed at the measure of its parallactic displacement (see GO 6526). Then we ask for one more exposure of PSR 0656+14, for which one PC observation is already in hand (GO 6136), to measure its proper motion. The distance values the Vela pulsar is highly disputed and a model-free measurement (or a reliable lower limit) would be very important, e.g., to assess the luminosity of this object at different wavelengths and measure how efficienctly it converts its rotational energy loss in optical, X and gamma radiation. ------------------------------------------------------------------------------------ 8328( 5) - 08/25/99 09:37 - [ 2] Observations Description ------------------------ Note that these targets have been previously detected by the HST, and we thus plan to use basically the same detector/filter set-ups and exposure times of the previous successful observations. Therefore for this program we ask: three PC exposures of Vela (3 orbits) with filter F555W to measure its parallax, and two additional exposures with filters F675W and F814W (2 orbits) to study, for the first time, the pulsar spectral distribution longwards 8000 $\AA$. For PSR 0656+14, we ask one PC exposure (2 orbits) with filter F555W to be coupled with our original jan. 1996 observation, taken with the same instrumental set up, to measure the pulsar proper motion. While for Vela the number of reference stars in the PC frame is certainly adequate for relative astrometry, regardless on the camera orientation, for PSR 0656+14 the situation is different. According to our experience, the ONLY COICHE to include a reasonable number of "good" reference stars is to CENTER the PC frame 8 ARCSEC NORTH of the pulsar position i.e. at: RA(2000): +06:59:48.12, DEC(2000): +14:14:29.53 and to keep the X, Y axis of the frame aligned along RA and DEC. Real Time Justification ----------------------- The three F555W observations of Vela should be performed at the time of their respective maximum parallactic displacements i.e. June/July 1999-Jan 2000- Jun/July 2000. Although the F675W/F814W observations are not time critical, we would prefer they are performed attached to the first visit of the target. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Paper Products: YES Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 8328( 5) - 08/25/99 09:37 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0835- STAR, NEUTRON STAR RA=8H 35M 20.67S +/- 0.019S, J2000 V = 23.6 4510 DEC=-45D 10' 35.75" +/- 0.29" B-V = 0.3 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1977.01 0.0032 -0.035 0.0 2 STAR- STAR, NEUTRON STAR RA=6H 59M 48.12S +/- 0.001S, J2000 V = 25 065948+14142 DEC=14D 14' 21.53" +/- 0.01" B-V = -0.2 1 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1989.07 0.0044 -0.028 0.0 8328( 5) - 08/25/99 09:37 - [ 4] Visit: 01 Visit Priority: Visit Requirements: PCS MODE F BETWEEN 30-JUN-1999 AND 30-JUL-1999 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0835-4 WFPC2 IMAGE PC1-FIX F555W 5407 CR-SPLIT=DEF,CR-TOLERANCE=0.2 1 2600 S 510 ------------------------------------------------------------------------------------------------------------------------------------ 8328( 5) - 08/25/99 09:37 - [ 5] Visit: 02 Visit Priority: Visit Requirements: PCS MODE F 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0835-4 WFPC2 IMAGE PC1-FIX F675W 6735 CR-SPLIT=DEF,CR-TOLERANCE=0.2 1 2600 S 510 ------------------------------------------------------------------------------------------------------------------------------------ 8328( 5) - 08/25/99 09:37 - [ 6] Visit: 03 Visit Priority: Visit Requirements: PCS MODE F 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0835-4 WFPC2 IMAGE PC1-FIX F814W 8269 CR-SPLIT=DEF,CR-TOLERANCE=0.2 1 2600 S 510 ------------------------------------------------------------------------------------------------------------------------------------ 8328( 5) - 08/25/99 09:37 - [ 7] Visit: 04 Visit Priority: Visit Requirements: PCS MODE F BETWEEN 1-JAN-2000 AND 30-JAN-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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0835-4 WFPC2 IMAGE PC1-FIX F555W 5407 CR-SPLIT=DEF,CR-TOLERANCE=0.2 1 2600 S 510 ------------------------------------------------------------------------------------------------------------------------------------ 8328( 5) - 08/25/99 09:37 - [ 8] Visit: 05 Visit Priority: Visit Requirements: PCS MODE F BETWEEN 30-JUN-2000 AND 30-JUL-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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0835-4 WFPC2 IMAGE PC1-FIX F555W 5407 CR-SPLIT=DEF,CR-TOLERANCE=0.2 1 2600 S 510 ------------------------------------------------------------------------------------------------------------------------------------ 8328( 5) - 08/25/99 09:37 - [ 9] Visit: 06 Visit Priority: Visit Requirements: PCS MODE F ORIENTation 45.0D TO 45.0D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-065948 WFPC2 IMAGE PC1-FIX F555W 5407 CR-SPLIT=0.5,CR-TOLERANCE=0.2 1 1600 S +141421 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-065948 WFPC2 IMAGE PC1-FIX F555W 5407 CR-SPLIT=0.5,CR-TOLERANCE=0.2 1 1600 S +141421 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-065948 WFPC2 IMAGE PC1-FIX F555W 5407 CR-SPLIT=0.5,CR-TOLERANCE=0.2 1 1200 S +141421 ------------------------------------------------------------------------------------------------------------------------------------ 8328( 5) - 08/25/99 09:37 - [ 10] Summary Form for Proposal 8328 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=DEF CR-TOLERANCE=0.2 CR-SPLIT=0.5 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PCS MODE F BETWEEN 30-JUN-1999 AND 30-JUL-1999 PCS MODE F PCS MODE F BETWEEN 1-JAN-2000 AND 30-JAN-2000 PCS MODE F BETWEEN 30-JUN-2000 AND 30-JUL-2000 PCS MODE F ORIENTation 45.0D TO 45.0D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F555W F675W F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names STAR-0835-4510 STAR-065948+141421 ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 5407 6735 8269 ------------------------------------------------------------------------------------------------------------------------------------