! $Id: 5484,v 5.1 1994/07/27 18:32:04 pepsa Exp $ coverpage: title_1: UNDERSTANDING THE GEMINGA (1E0630+178) OPTICAL COUNTERPART title_2: CYCLE 4 HIGH sci_cat: HOT STARS sci_subcat: NEUTRON STARS proposal_for: GO pi_fname: GIOVANNI pi_mi: F. pi_lname: BIGNAMI pi_inst: CNR ISTITUTO DI FISICA COSMICA, MILANO pi_country: ITALY pi_phone: 39-2-2367587 num_pri: 1 wf_pc: Y foc: Y time_crit: Y off_fname: GIULIANO off_lname: BOELLA off_title: DIRECTOR off_inst: 6408 off_addr_1: VIA BASSINI, 15 off_city: MILANO off_zip: 20133 off_country: ITALY off_phone: 39-2-2363542 ! end of coverpage abstract: line_1: The recent discovery of a common X/Gamma periodicity for GEMINGA line_2: and of the proper motion of the optical candidate have finally closed line_3: the X/Gamma/optical identification chain. The object is a rotating line_4: neutron star, the only one invisible in radio, but visible in the line_5: optical. Two main problems remain open for the understanding of line_6: Geminga: the physical characteristics of its emission and its distance. line_7: The first was the aim of our Cycle 1 proposal N.2525, approved with high line_8: priority but then deferred. In it we proposed to study this unique line_9: object through few color photometry with the FOC. The distance problem line_10: could be solved by measuring Geminga's annual parallax: this is the line_11: aim of the ongoing DD proposal N.4593, already approved for several PC line_12: observations covering both Cycles 3 and 4. The current proposal is a line_13: merging of the two, exploiting the post-refurbishment capabilities of line_14: the HST instruments. Establishing a reliable flux in line_15: near UV is crucial for grasping the overall energy balance and for line_16: distinguishing between non-thermal and thermal emission models, line_17: especially in comparison with the soft X-ray spectral information now line_18: available from ROSAT. Obviously, a measurement of the parallax would line_19: give for the first time a quantitative assesment of the multi-band line_20: luminosities of a neutron star. ! ! end of abstract general_form_proposers: lname: BIGNAMI fname: GIOVANNI inst: 6408 country: ITALY esa: Y ! lname: CARAVEO fname: PATRIZIA inst: 6408 country: ITALY esa: Y ! lname: MEREGHETTI fname: SANDRO inst: 6408 country: ITALY esa: Y ! lname: MIGNANI fname: ROBERTO inst: 6408 country: ITALY esa: Y ! lname: TAFF fname: LAURENCE inst: 3470 country: USA esa: N ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: For the proposed scientific objectives, we need the FOC in direct image line_2: mode at F/96 (with F320W filter),thus reaching the required sensitivity line_3: in about 8000 sec. line_4: For the PC images, we need to take three sequences of 2 exposures of line_5: about one orbit each. The first pair of one orbit exposure should be line_6: around March 21,1994,the second around Sept.21,1994 (when the parallatic line_7: displacement is maximum) and the third around March 21,1995. ! question: 3 section: 2 line_1: ! question: 4 section: 1 line_1: Near UV measurments are not possible from the ground, line_2: so that the post COSTAR FOC appears as a line_3: natural choice. line_4: To measure the parallatic displacement we need a very accurate position of our line_5: object (G"), together with few reference stars, taken 6 months apart. line_6: The very accurate position coupled with a large FOV can be obtained with the line_7: WFPC2. ! question: 5 section: 1 line_1: While the FOC image is time independent, the WFPC2 images must be performed line_2: when the parallatic displacement is expected to be maximum, i.e. near the spring line_3: and fall equinoxes.The FOC exposure has been added to the second pair of line_4: WFPC2 images in order to save acquisition time. ! question: 6 section: 1 line_1: NONE ! ! question: 8 section: 1 line_1: NONE ! question: 9 section: 1 line_1: NO RESULTS YET. TWO PROPOSALS DEVOTED TO THE STUDY OF THE GEMINGA line_2: OPTICAL COUNTERPART HAVE BEEN APPROVED, NAMELY 2525 FOR CYCLE 1 line_3: AND 4593 FOR CYCLE 3. WHILE PROP.2525 WAS DEFERRED, PROP. 4593 line_4: WAS PARTIALLY CARRIED OUT BUT THE WFPC1 WAS NOT ABLE TO DETECT line_5: THE FAINT GEMINGA OPTICAL COUNTERPART. BECAUSE OF THE FAILURE line_6: TO DETECT THE SOURCE, PART OF THE OBSERVING TIME ALLOCATED TO line_7: PROPOSAL 4593 WAS GIVEN UP. ! question: 10 section: 1 line_1: The Istituto di Fisica Cosmica has VAX and SUN WS equipped with MIDAS and IRAF line_2: (With STSDAS). Ph.D. students from the Istituto di Fisica of the Milan line_3: University normally take active part in the data analysis. line_4: Funds for the italian partecipants will be provided by the Agenzia Spaziale line_5: Italiana and by the CNR. ! !end of general form text general_form_address: lname: BIGNAMI fname: GIOVANNI category: PI inst: 6408 country: ITALY phone: 39-2-2367587 telex: gfb@ifctr.mi.cnr.it ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: STAR-0633+1746 name_2: GEMINGA name_3: 1E0630+178 descr_1: A, 160 pos_1: RA = 06H 33M 53.98S +/- 0.5", pos_2: DEC = 17D 46' 11.20" +/- 0.5" equinox: J2000 fluxnum_1: 1 fluxval_1: V = 25.3 +/- 0.2, E(B-V)=0.15 fluxnum_2: 2 fluxval_2: B = 26.5 +/- 0.5 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 targname: STAR-0633+1746 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F555W wavelength: 5407 num_exp: 1 time_per_exp: 1400S s_to_n: 10 fluxnum_1: 1 priority: 1 req_1: AT 21-MAR-94 +/- 7D; CYCLE 4; req_2: GROUP 1-2 NO GAP; req_3: SAME ORIENT FOR 2 AS 1; ! linenum: 2.000 targname: STAR-0633+1746 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F555W wavelength: 5407 num_exp: 1 time_per_exp: 1700S s_to_n: 10 fluxnum_1: 1 priority: 1 req_1: CYCLE 4; ! linenum: 3.000 targname: STAR-0633+1746 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F555W wavelength: 5407 num_exp: 1 time_per_exp: 1400S s_to_n: 10 fluxnum_1: 1 priority: 1 req_1: AT 21-SEP-94 +/- 7D; CYCLE 4; req_2: GROUP 3-4.5 NO GAP; req_3: SAME ORIENT FOR 4 AS 3; ! linenum: 4.000 targname: STAR-0633+1746 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F555W wavelength: 5407 num_exp: 1 time_per_exp: 1700S s_to_n: 10 fluxnum_1: 1 priority: 1 req_1: CYCLE 4; ! linenum: 4.500 targname: STAR-0633+1746 config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F320W wavelength: 3360 num_exp: 1 time_per_exp: 8000S s_to_n: 10 fluxnum_1: 2 priority: 1 req_1: CYCLE 4; ! linenum: 5.000 targname: STAR-0633+1746 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F555W wavelength: 5407 num_exp: 1 time_per_exp: 1400S s_to_n: 10 fluxnum_1: 1 priority: 1 req_1: AT 21-MAR-95 +/- 7D; CYCLE 4; req_2: GROUP 5-6 NO GAP; req_3: SAME ORIENT FOR 6 AS 5; ! linenum: 6.000 targname: STAR-0633+1746 config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F555W wavelength: 5407 num_exp: 1 time_per_exp: 1700S s_to_n: 10 fluxnum_1: 1 priority: 1 req_1: CYCLE 4; ! ! end of exposure logsheet ! No scan data records found