Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 2525c Report Date: 09-May-96:17:10 Version: ********** Check-in Date: ********** 1.Proposal Title: SEARCHING FOR THE GEMINGA (1E 0630+178) COUNTERPART WITH MULTI-COLOUR PHOTOMETRY ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID STELLAR ASTROPHYSICS GO Sub Category NEUTRON STARS ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Dr. Giovanni F. Bignami CNR, INSTITUTE OF COSMIC PHY ITALY 39-2-2367587 ------------------------------------------------------------------------------------ 7. Abstract The optical identification of 1E0630+178 is a long-standing puzzle for which the resources of ground-based astronomy have definitely been exhausted. The importance of understanding the nature of this object lies not only with the X-ray source, in itself unique, but also because it is most likely associated with the high-energy gamma-ray source Geminga, With a gamma-ray/X-ray flux ratio of about 1,000, and the same again (or more) X-ray/optical, the source is very likely to be associated with a compact object, probably a neutron star, as suggested also by the reported X-ray periodicity. The ST with multi colour photometry by the FOC can clearly help investigate the best optical candidate found so far (mb=26.5), and also look for others. ------------------------------------------------------------------------------------ 8. Scientific Key Words: GEMINGA-IDENTIFICATION-X/GAMMA RAY SOURCES-NETRON STAR ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 4.00 par: 0 10. Num targs pri: 1 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FOC ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 2525c PI: Dr. Giovanni F. Bignami Proposal Title: SEARCHING FOR THE GEMINGA (1E 0630+178) COUNTERPART WITH MULTI-COLOUR PHOTOMETRY ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Dr. P. A. Caraveo CNR, INSTITUTE OF COSMIC PHYSICS ITALY X Dr. S. Mereghetti CNR, INSTITUTE OF COSMIC PHYSICS ITALY X P.I. Giovanni F. Bignami CNR, INSTITUTE OF COSMIC PHYSICS ITALY X ------------------------------------------------------------------------------------ 3. Description of proposed observations. For the porposed scientific objectives, we need the FOC in direct image mode at f/96 (with blue and ultraviolet filters), thus reaching the required sensitivity in one to two hours, depending on the filters used. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. As mentioned in the scientific justification, ground-based astronomy has beem fully exploited in the case of Geminga. The use of ST is clearly required by the faintness of the objectives to be studied. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. The observing time required by this program has been computed according to the FOC handbook using the values of the magnitudes of G",i.e. the faintest object detected up to now in the error box, mr= 25.54 +/- 0.3, mv=25.37 +/- 0.2, mb=26.5 +/- 0.5. Realistic interstellar extinction values have been considered, as well as various sky background conditions. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). The Istituto di Fisica Cosmica has access to HP1000 and VAX computers equipped with IHAP and MIDAS software packages for image processing. Students from the Istituto di Fisica of the Universita' di Milano normally take active part in the data analysis. Funds will be provided by the Agenzia Spaziale Italiana and by the CNR. ------------------------------------------------------------------------------------ 11. Address Information Name: GIOVANNI F. BIGNAMI Category: PI Institution: ISTITUTO DI FISICA COSMICA Address: VIA BASSINI, 15 City: MILANO 20133 State: Zip Code: Country: ITALY Telephone: Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 2525c [ 3] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR- STAR RA = 06H 33M 53.98S +/- J2000 1 V = 25.3 +/- 0.2, E(B-V)=0.15 0633+1746 X-RAY STAR 0.5", 2 B = 26.5 +/- 0.5 GEMINGA NEUTRON STAR DEC = 17D 46' 11.20" +/- 0.5" Comments: THE LINES 1 AND 2 ABOVE REFER TO THE FAINTEST KNOWN OBJECT IN THE FIELD. STILL FAINTER OBJECTS MAY ALSO BE OF INTEREST. ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 2525c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR- FOC/96 IMAGE 512X512 F430W 1 4000S 10 2 1 0633+1746 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR- FOC/96 IMAGE 512X512 F320W 1 8540S 10 2 1 0633+1746 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 2525c [ 5] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOC/96 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 4.00 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR ASTROPHYSICS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category NEUTRON STARS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F430W F320W ------------------------------------------------------------------------------------------------------------------------------------ Target Names STAR-0633+1746 GEMINGA ------------------------------------------------------------------------------------------------------------------------------------