6836( 5) - 02/20/97 13:48 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6836 Version: 5 Check-in Date: 20-Feb-1997 13:47:28 1.Proposal Title: Light Curve of an Eclipsing Millisecond Pulsar Companion ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle BINARIES AND STAR FOR GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: JON BELL NRAL CoI: Ben Stappers Mount Stromlo and Siding Spring N Observatories CoI: Andy Fruchter Space Telescope Science Institute N CoI: Shri Kulkarni California Institute of Technology N CoI: Marten van Kerkwijk California Institute of Technology N ------------------------------------------------------------------------------------ 6. Abstract PSR J2051--0827 is an exciting new millisecond pulsar which is in a 2.38 hour circular orbit about a 0.03 solar mass companion which eclipses the pulsed radiation from the pulsar for 20 minutes each orbit. The companion is only the second eclipsing millisecond pulsar companion identified optically. It provides an excellent opportunity to test the evolutionary scenarios implied for eclipsing and solitary millisecond pulsar systems. An accurate measurement of the magnitude and colour temperature of the companion as it passes through minimum light will allow us to distinguish whether the companion is tidally powered, or bloated due to impinging radiation, or has a radius which is consistent with a low mass white dwarf. The nature and radius of the companion are vital discriminants in determining the source of the eclipsing material and whether the companion will eventually be ablated. The companion may also be the coldest object known providing a unique opportunity to study the emergent spectrum with a combined HST optical and ground based infrared program. ------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 2] Observations Description ------------------------ We propose to take 5 exposures per orbit for 7 space craft orbits. We chose the photometric filters because we believe that the better calibration outweighs signal-to- noise considerations. We will spend 4 orbits in F675W and 3 orbits F814W since the companion is brighter at longer wavelengths. The pulsar orbital phases for exposures are chosen to give more exposures near minimum light, and less at orbital phases away from minimum light. We wish to have each pair of orbits with the two different filters taken at the same pulsar orbital phases and close together in time, in order to minimise the effects that any long term variations in the color. However, the pairs can be well separated in time, allowing us to constrain long term variations in luminosity. Real Time Justification ----------------------- We wish to concentrate the observations between pulsar orbital phases 0.1 and 0.4 (ie during minimum light) in order to probe the dark side of the companion as deeply as possible. The bright side of the companion is sufficiently bright to be observed from ground based facilities. Since orbital period of the system is known to millisecond accuracy, we can provide the necessary ephemeris for planning the observations. We intend to propose for Keck observations to obtain an infrared light curve of this system, as we have already done for PSR B1957+20 (see Figure 2). By having the light curve in several widely separated bands, one obtains in effect a luminosity curve. With this, it will be possible to constrain the backside temperature even in the case that a crescent of the bright side is still visible. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: ------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 PSRJ2051- STAR,BINARY PULSAR RA=20H 51M 07.5119S +/- J2000.0 R = 23.34+/-0.06 0827 0.0003S,DEC=-08D 27' 37.78" +/- R-I = 0.7+/-0.17 0.02" E(B-V) = 0.045+/-0.015 Comments: The flux at min light will be substantially less than above 6836( 5) - 02/20/97 13:48 - [ 4] Visit: 01 Visit Requirements: GROUP 01-02 WITHIN 10D PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 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 PSRJ2051-08 WFPC2 IMAGE PC1 F675W CLOCKS=YES 2 800 S PHASE 0.07 TO 0.11 27 ------------------------------------------------------------------------------------------------------------------------------------ 2 PSRJ2051-08 WFPC2 IMAGE PC1 F675W CLOCKS=YES 1 500 S 27 ------------------------------------------------------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 5] Visit: 02 Visit Requirements: PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 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 PSRJ2051-08 WFPC2 IMAGE PC1 F814W CLOCKS=YES 2 800 S PHASE 0.07 TO 0.11 27 ------------------------------------------------------------------------------------------------------------------------------------ 2 PSRJ2051-08 WFPC2 IMAGE PC1 F814W CLOCKS=YES 1 500 S 27 ------------------------------------------------------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 6] Visit: 03 Visit Requirements: GROUP 03-04 WITHIN 10D PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 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 PSRJ2051-08 WFPC2 IMAGE PC1 F675W CLOCKS=YES 2 800 S PHASE 0.18 TO 0.22 27 ------------------------------------------------------------------------------------------------------------------------------------ 2 PSRJ2051-08 WFPC2 IMAGE PC1 F675W CLOCKS=YES 1 500 S 27 ------------------------------------------------------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 7] Visit: 04 Visit Requirements: PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 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 PSRJ2051-08 WFPC2 IMAGE PC1 F814W CLOCKS=YES 2 800 S PHASE 0.18 TO 0.22 27 ------------------------------------------------------------------------------------------------------------------------------------ 2 PSRJ2051-08 WFPC2 IMAGE PC1 F814W CLOCKS=YES 1 500 S 27 ------------------------------------------------------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 8] Visit: 05 Visit Requirements: GROUP 05-06 WITHIN 10D PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 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 PSRJ2051-08 WFPC2 IMAGE PC1 F675W CLOCKS=YES 2 800 S PHASE 0.96 TO 0.999 27 ------------------------------------------------------------------------------------------------------------------------------------ 2 PSRJ2051-08 WFPC2 IMAGE PC1 F675W CLOCKS=YES 1 500 S 27 ------------------------------------------------------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 9] Visit: 06 Visit Requirements: PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 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 PSRJ2051-08 WFPC2 IMAGE PC1 F814W CLOCKS=YES 2 800 S PHASE 0.96 TO 0.999 27 ------------------------------------------------------------------------------------------------------------------------------------ 2 PSRJ2051-08 WFPC2 IMAGE PC1 F814W CLOCKS=YES 1 500 S 27 ------------------------------------------------------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 10] Visit: 07 Visit Requirements: PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 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 PSRJ2051-08 WFPC2 IMAGE PC1 F675W CLOCKS=YES 2 800 S PHASE 0.07 TO 0.11 27 ------------------------------------------------------------------------------------------------------------------------------------ 2 PSRJ2051-08 WFPC2 IMAGE PC1 F675W CLOCKS=YES 1 500 S 27 ------------------------------------------------------------------------------------------------------------------------------------ 6836( 5) - 02/20/97 13:48 - [ 11] Summary Form for Proposal 6836 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CLOCKS=YES ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category BINARIES AND STAR FORMATION ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GROUP 01-02 WITHIN 10D PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 PHASE 0.07 TO 0.11 GROUP 03-04 WITHIN 10D PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 PHASE 0.18 TO 0.22 GROUP 05-06 WITHIN 10D PERIOD 0.0991102667D AND ZERO-PHASE JD2449642.673030 PHASE 0.96 TO 0.999 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F675W F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names PSRJ2051-0827 ------------------------------------------------------------------------------------------------------------------------------------