! $Id: 5697,v 10.1 1995/01/17 15:00:29 pepsa Exp $ coverpage: title_1: CIR-X1 REVISITED: SPECTROSCOPY THROUGHOUT THE 16.6 title_2: DAY CYCLE OF THE REAL OPTICAL CANDIDATE: CYCLE 4 CARRYOVER sci_cat: STELLAR ASTROPHYSICS sci_subcat: X-RAY BINARIES proposal_for: GO/CAR cont_id: 4930 pi_fname: PATRIZIA pi_mi: A pi_lname: CARAVEO pi_inst: ISTITUTO DI FISICA COSMICA DEL CNR pi_country: ITALY pi_phone: 39-2-2367587 hours_pri: 2.80 num_pri: 2 fos: Y time_crit: Y off_fname: GIULIANO off_lname: BOELLA off_title: DIRECTOR off_inst: ISTITUTO DI FISICA COSMICA DEL CNR off_addr_1: VIA BASSINI, 15 off_city: MILANO 20133 off_country: ITALY off_phone: 39-2-2363542 ! end of coverpage abstract: line_1: Circinus X-1 is a very strong and highly variable X-ray, IR and radio line_2: source. Its optical identification was, until very recently, line_3: wrongly attributed to a star which recent NTT observations, done in line_4: superb seeing, have resolved in three objects.Of these one, very red, line_5: coincides with the accurate VLA position for the radio source line_6: (varying in phase with the X-ray), and is thus the real candidate. line_7: Only HST can now do meaningful line_8: work on the true counterpart of Cir X-1: even small seeing conditions line_9: variations would render incomparable measurements taken from the ground line_10: over the 16.6 day (binary\?) source cycle. A new line_11: FOS spectrum, taken at critical line_12: time during the cycle, will help to understand this line_13: 17-19 mag variable object, responsible for a truly bizarre line_14: X-ray/radio object. ! ! end of abstract general_form_proposers: lname: BIGNAMI fname: GIOVANNI mi: F inst: ISTITUTO DI FISICA COSMICA DEL CNR country: ITALY esa: Y ! lname: CARAVEO fname: PATRIZIA title: PI mi: A inst: ISTITUTO DI FISICA COSMICA DEL CNR country: ITALY esa: Y ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: We plan line_2: to use the red detector line_3: of the FOS with the grism G570H using a 0.5 arcsec aperture line_4: to obtain a spectrum of line_5: the proposed counterpart of Cir X-1. We have chosen this set-up line_6: in order to cover Halpha as well as the most prominent ISM absorption features line_7: which could give and independent measure of the source distance. line_8: We need to use the small aperture in order line_9: to avoid contamination from the nearby (about 1.5 arcsec) field line_10: stars. ! question: 4 section: 1 line_1: In order to study the temporal behaviour of the Cir X1 optical counterpart, line_2: now known to lye 1.5 arcsec from two unrelated objects,one needs EXCELLENT line_3: and CONSTANT SEEING CONDITIONS. Clearly this can only be achievable with HST line_4: whose angular resolution is both very good and stable. ! question: 6 section: 1 line_1: Since the strong and clearly correlated X-ray,Radio,IR flux variabilities of line_2: Cir X-1 are known to follow a 16.6 day cyclic behaviour. For this corryover, line_3: we propose to observe the source during the X-ray maximum. ! ! question: 9 section: 1 line_1: 3432 and 4930: same title cycle 2. line_2: 3432 Early acquisition, using WFPC, to compute the offset parameters needed to line_3: point our faint target. line_4: 4930 three FOS spectra taken using the PRISM as disperser: not line_5: satisfactory owing to non linear dispersion and very poor resolution line_6: in the red part of the spectrum. ! question: 10 section: 1 line_1: The Istituto di Fisica Cosmica has SUN WS equipped with MIDAS and line_2: IRAF (with STSDAS). Students from the Istituto di Fisica of the Milano line_3: University normally take active part in the data analysis. line_4: Funds will be provided by the Agenzia Spaziale Italiana and by CNR ! !end of general form text general_form_address: lname: CARAVEO fname: PATRIZIA mi: A category: PI inst: ISTITUTO DI FISICA COSMICA DEL CNR addr_2: VIA BASSINI, 15 city: MILANO 20133 country: ITALY phone: 39-2-2367587 telex: 313839 ! ! end of general_form_address records fixed_targets: targnum: 2 name_1: CIR-X1-OFFSET descr_1: I,603 pos_1: RA = 15H 20M 39.683S +/- 0.1", pos_2: DEC =-57D 09' 16.42"+/- 0.1" equinox: 2000 comment_1: OFFSET STAR fluxnum_1: 1 fluxval_1: R = 18.7 +/- 0.5 ! targnum: 3 name_1: STAR-1520-5710-SPECTRUM name_2: CIR-X1 descr_1: B,165 pos_1: RA-OFF = 1.173S +/- 0.1S, pos_2: DEC-OFF = -43.379" +/- 0.1", pos_3: FROM 2 equinox: 2000 comment_1: OFFSET FROM 2 fluxnum_1: 1 fluxval_1: R = 19.0 +/- 0.5 fluxnum_2: 1 fluxval_2: V = 20.0 +/- 0.5 fluxnum_3: 1 fluxval_3: I = 18.6 +/- 0.5 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 8.000 targname: CIR-X1-OFFSET config: FOS/RD opmode: ACQ/PEAK aperture: 4.3 sp_element: MIRROR num_exp: 1 time_per_exp: 25S priority: 1 req_1: ONBOARD ACQ FOR 8.1; req_2: req_3: CYCLE 4/8-9; param_1: SEARCH-SIZE-X=1 param_2: SEARCH-SIZE-Y=3 param_3: SCAN-STEP-Y=1.204 comment_1: ASSUME A K5 V STAR comment_2: FOR THE OFFSET STAR. ! linenum: 8.100 targname: CIR-X1-OFFSET config: FOS/RD opmode: ACQ/PEAK aperture: 1.0 sp_element: MIRROR num_exp: 1 time_per_exp: 25S priority: 1 param_1: SEARCH-SIZE-X=6 param_2: SEARCH-SIZE-Y=2 param_3: SCAN-STEP-X=0.602 param_4: SCAN-STEP-Y=0.602 req_1: ONBOARD ACQ FOR 8.2; req_2: ! linenum: 8.200 targname: STAR-1520-5710-SPECTRUM config: FOS/RD opmode: ACQ/PEAK aperture: 0.5 sp_element: MIRROR num_exp: 1 time_per_exp: 35S priority: 1 param_1: SEARCH-SIZE-X=3 param_2: SEARCH-SIZE-Y=3 param_3: SCAN-STEP-X=0.29 param_4: SCAN-STEP-Y=0.29 req_1: ONBOARD ACQ FOR 8.3; ! linenum: 8.300 targname: STAR-1520-5710-SPECTRUM config: FOS/RD opmode: ACQ/PEAK aperture: 0.3 sp_element: MIRROR num_exp: 1 time_per_exp: 50S priority: 1 param_1: SEARCH-SIZE-X=4 param_2: SEARCH-SIZE-Y=4 param_3: SCAN-STEP-X=0.11 param_4: SCAN-STEP-Y=0.11 req_1: ONBOARD ACQ FOR 9; ! linenum: 9.000 targname: STAR-1520-5710-SPECTRUM config: FOS/RD opmode: ACCUM aperture: 0.5 sp_element: G570H wavelength: 4571-6820 num_exp: 1 time_per_exp: 86M s_to_n: 10 fluxnum_1: 1 priority: 1 req_1: PHASE 0.0 +/- 0.1; req_2: PERIOD 16.5678D +/- 0.0000353D; req_3: ZERO-PHASE JD 2443076.87 +/- 0.01D; ! ! end of exposure logsheet