! File: 2941C.PROP ! Database: PEPDB ! Date: 17-FEB-1994:23:44:36 coverpage: title_1: HIGH SPEED ASTROMETRY - A SEARCH FOR PLANETARY COMPANIONS title_2: TO LOW-MASS STARS PART THREE sci_cat: SOLAR SYSTEM proposal_for: GTO/AST longterm: 2 pi_title: DR. pi_fname: WILLIAM pi_mi: H. pi_lname: JEFFERYS pi_inst: UNIVERSITY OF TEXAS pi_country: USA pi_phone: (512)471-3000 keywords_1: FINE GUIDANCE SENSORS, FGS, STELLAR COMPANIONS, keywords_2: EXTRASOLAR PLANETS hours_pri: 35.00 num_pri: 6 fgs: Y pi_position: PROFESSOR ! end of coverpage abstract: line_1: We propose to test the hypothesis that jupiter-like planets line_2: are formed at distances from the primary dictated by the line_3: 'freezing' temperature of the volatiles which comprise jovian line_4: planets. Predicted periods for jovian planets orbiting this sample line_5: of very late-type, low-mass stars range from 70 to 160 days. line_6: We shall monitor the positions of these nearby late-M stars with line_7: a time-resolution of 4 to 10 days in an attempt to detect positional line_8: perturbations caused by possible jovian companions. Detection line_9: limits for these proposed targets lie between 0.4 and one Jupiter line_10: mass. ! ! end of abstract general_form_proposers: lname: JEFFERYS fname: WILLIAM title: DR. mi: H. inst: UNIVERSITY OF TEXAS country: USA ! lname: BENEDICT fname: GEORGE title: DR. mi: F. inst: UNIVERSITY OF TEXAS country: USA ! lname: DUNCOMBE fname: RAYNOR title: DR. mi: L. inst: UNIVERSITY OF TEXAS country: USA ! lname: HEMENWAY fname: PAUL title: DR. mi: D. inst: UNIVERSITY OF TEXAS country: USA ! lname: SHELUS fname: PETER title: DR. mi: S. inst: UNIVERSITY OF TEXAS country: USA ! lname: FRANZ fname: OTTO title: DR. mi: G. inst: LOWELL OBSERVATORY country: USA ! lname: FREDRICK fname: LAURENCE title: DR. mi: W. inst: UNIVERSITY OF VIRGINIA country: USA ! lname: VAN ALTENA fname: WILLIAM title: DR. mi: F. inst: YALE UNIVERSITY country: USA ! ! end of general_form_proposers block general_form_text: question: 2 section: 1 line_1: Are planetary systems prevelent? Can we derive an line_2: observing strategy which will increase the likelihood of line_3: answering this question? line_4: Assumptions: line_5: 1. The processes which resulted in our Solar System are not line_6: unique. line_7: 2. A star's pre-planetary nebula scales ( in temperature ) as line_8: the luminosity ( bolometric absolute magnitude ) of the central line_9: star. line_10: 3. Looking ( astrometrically ) for planets implies looking for line_11: gas giants orbiting low-mass stars ( most favorable mass-ratio ). line_12: 4. Gas giants form at about the same temperature in the line_13: pre-planetray nebula and hence at a predictable distance line_14: from the central star. line_15: 5. The distance between a gas giant and the central star scales as line_16: 5.2*sqrt(Lstar/Lsun), where 5.2 AU represents the line_17: Sun - Jupiter separation. line_18: Choosing the lowest-mass, nearest stars known to be either line_19: wide binaries or single stars, one can calculate the period line_20: of a Jupiter-mass planet orbiting each at a distance calculated to line_21: provide the proper formation temperature. These periods range line_22: from 74 to 155 days. Values for the periods are quite uncertain line_23: since neither bolometric corrections nor masses for late-M ! question: 2 section: 2 line_1: stars are well known. Six primary objects will be observed. Should line_2: HST efficiency be greater than predicted, the two line_3: secondary objects will be observed. line_4: Black and Scargle ( Ap. J. 263:854. 1982 ) recommend a line_5: maximum observing interval of one-half the predicted period. line_6: Since we do not know the period of a postulated gas giant, we have line_7: chosen to take 25 observations over somewhat more than one line_8: predicted period, to provide adequate coverage. Thus, observing line_9: intervals range from 4 to 8 days. Gatewood et. al. line_10: ( Icarus 41:205. 1980 ) have devised an algorithm for line_11: calculating the minimum detectable mass of an unseen companion. line_12: This was used to obtain the results below for the Primary Targets. line_13: PARAMETER PROXIMA BARNARD W359 L726-8A L726-8B R248 line_14: --------- ------- ------- ---- ------- ------- ---- line_15: parallax 0.757 0.553 0.428 0.370 0.370 0.314 line_16: vmag 11.22 9.54 13.55 12.95 12.50 12.29 line_17: abs. bol. mag. 11.7 10.9 12.2 11.76 12.14 12.0 line_18: Sp type dM5e M5 M8e M6e M6e M6e line_19: stellar line_20: mass/solar 0.10 0.15 0.07 0.12 0.11 0.07 line_21: lum/solar 0.0016 0.0033 0.001 0.001 0.001 0.001 line_22: gg r in AU 0.21 0.30 0.16 0.17 0.17 0.16 line_23: gg P in days 106 153 88 82 82 88 ! question: 2 section: 3 line_1: Number of obs 30 30 30 30 30 30 line_2: obs spacing line_3: in days 5 8 4 4 4 4 line_4: Minimum detectable line_5: mass/solar 0.00036 0.00064 0.0007 0.001 0.001 0.0008 line_6: __________________________________ line_7: gg r = gas giant/primary seperation line_8: gg P = gas giant orbital period ! question: 3 section: 1 line_1: Acquire guide stars in the FGS units selected for guiding. line_2: Measure target, then reference stars, then target. line_3: Observations will be spaced 4 to 10 days over a time span of 100 to 250 days, line_4: depending on the target. Use FGS unit designated as Astrometry Prime. line_5: Cycle 0 = Exposures 13, 23 line_6: Cycle 1 = Exposures 13, 23, 33 ,45, 53, 63 line_7: Cycle 2 = Exposures 63 ! question: 4 section: 1 line_1: The minimum detectable mass depends directly on the accuracy line_2: of the positional measurements. Ground-based accuracies rarely exceed line_3: 50 milliarcseconds (mas). The assumed 2 mas accuracy of HST should line_4: let us detect 25 times less massive companions than from the ground. ! question: 7 section: 1 line_1: Data reduction will be performed using the ADRS within the SDAS line_2: system at STScI with other analyses being performed in Austin. line_3: The data will be put into the SDAS format for analysis using the line_4: GAUSS module. ! question: 13 section: 1 line_1: "High-Speed" Astrometry will be carried out on 6-8 low-mass stars in an line_2: effort to detect positional perturbations due to jovian planets. We assume line_3: that such planets will lie close to these low luminosity stars, and, hence, line_4: have fairly short orbital periods. Observations will be spaced 4 to 8 days line_5: apart. ! !end of general form text general_form_address: lname: JEFFERYS category: PI ! lname: BENEDICT fname: GEORGE mi: F. title: DR. category: CON addr_1: DEPARTMENT OF ASTRONOMY city: AUSTIN state: TX zip: 78712 country: USA phone: (512)471-3448 ! lname: JEFFERYS fname: WILLIAM mi: H. title: DR. category: PI inst: UNIVERSITY OF TEXAS addr_1: DEPARTMENT OF ASTRONOMY city: AUSTIN state: TX zip: 78712 country: USA phone: (512)471-1455 telex: TEXASTRO ! ! end of general_form_address records fixed_targets: targnum: 29 name_1: BARNARDS-STAR descr_1: HIGHEST PROPER MOTION STAR pos_1: RA = 17H 55M 20.94S +/- 2", pos_2: DEC = +4D 39' 21.40" +/- 2" equinox: 1950.0 pos_epoch_bj: B pos_epoch_yr: 1985.50 ra_pm_val: -0.050000 ra_pm_unct: 0.000667 dec_pm_val: 10.3100 dec_pm_unct: 0.0100 an_prlx_val: 0.5520 an_prlx_unct: 0.0050 fluxnum_1: 1 fluxval_1: V = 9.54 +/- 0.02 ! targnum: 30 name_1: BARNARD-GSC-1-REF descr_1: REFERENCE STAR FOR BARNARDS STAR pos_1: RA = 269.47687D +/- 0.0003D, pos_2: DEC = +4.680570D +/- 0.0003D equinox: 2000.0 fluxnum_1: 1 fluxval_1: V = 13.26 +/- 0.6 ! targnum: 31 name_1: BARNARD-75-REF descr_1: REFERENCE STAR FOR BARNARDS STAR pos_1: RA = 269.436264D +/- 0.0003D, pos_2: DEC = +4.690059D +/- 0.0003D equinox: 2000.0 fluxnum_1: 1 fluxval_1: V = 16.84 +/- 0.6 ! targnum: 32 name_1: BARNARD-81-REF descr_1: REFERENCE STAR FOR BARNARDS STAR pos_1: RA = 269.437087D +/- 0.0003D, pos_2: DEC = +4.679343D +/- 0.0003D equinox: 2000.0 fluxnum_1: 1 fluxval_1: V = 15.5 +/- 0.6 ! targnum: 33 name_1: BARNARD-90-REF descr_1: REFERENCE STAR FOR BARNARDS STAR pos_1: RA = 269.42924D +/- 0.0003D, pos_2: DEC = +4.666314D +/- 0.0003D equinox: 2000.0 fluxnum_1: 1 fluxval_1: V = 15.5 +/- 0.6 ! targnum: 34 name_1: BARNARD-GSC-2-REF descr_1: REFERENCE STAR FOR BARNARDS STAR pos_1: RA = 269.456590D +/- 0.0003D, pos_2: DEC = +4.706910D +/- 0.0003D equinox: 2000.0 fluxnum_1: 1 fluxval_1: V = 14.52 +/- 0.6 ! targnum: 35 name_1: BARNARD-93-REF descr_1: REFERENCE STAR FOR BARNARDS STAR pos_1: RA = 269.457916D +/- 0.0003D, pos_2: DEC = +4.674444D +/- 0.0003D equinox: 2000.0 fluxnum_1: 1 fluxval_1: V = 16.54 +/- 0.6 ! targnum: 36 name_1: BARNARD-GSC-3-REF descr_1: REFERENCE STAR FOR BARNARDS STAR pos_1: RA = 269.466480D +/- 0.0003D, pos_2: DEC = +4.705630D +/- 0.0003D equinox: 2000.0 fluxnum_1: 1 fluxval_1: V = 11.18 +/- 0.6 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 20.000 sequence_1: DEFINE sequence_2: SEQ21 targname: BARNARDS-STAR config: FGS opmode: POS aperture: PRIME sp_element: F583W num_exp: 1 time_per_exp: 10S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: DATA-RATE=32 req_3: SEQ 20-26 NON-INT; req_5: GUID TOL 0.007" comment_1: AVOID TERMINATOR CROSSING ! linenum: 20.500 sequence_1: DEFINE sequence_2: SEQ21 targname: BARNARD-GSC-1-REF config: ^ opmode: ^ aperture: ^ sp_element: ^ num_exp: ^ time_per_exp: 52S s_to_n: ^ fluxnum_1: ^ priority: ^ param_1: ^ ! linenum: 21.000 sequence_1: DEFINE sequence_2: SEQ21 targname: BARNARD-75-REF config: ^ opmode: ^ aperture: ^ sp_element: ^ num_exp: ^ time_per_exp: ^ s_to_n: ^ fluxnum_1: ^ priority: ^ param_1: ^ req_1: DO FOR TARG 31-33; comment_1: OBSERVE ONLY THOSE REFERENCE STARS comment_2: WITHIN THE ASTROMETRY PICKLE ! linenum: 22.000 sequence_1: DEFINE sequence_2: SEQ21 targname: BARNARDS-STAR config: ^ opmode: ^ aperture: ^ sp_element: ^ num_exp: ^ time_per_exp: 10S s_to_n: ^ fluxnum_1: ^ priority: ^ param_1: ^ ! linenum: 23.000 sequence_1: DEFINE sequence_2: SEQ21 targname: BARNARD-GSC-1-REF config: ^ opmode: ^ aperture: ^ sp_element: ^ num_exp: ^ time_per_exp: 52S s_to_n: ^ fluxnum_1: ^ priority: ^ param_1: ^ ! linenum: 24.000 sequence_1: DEFINE sequence_2: SEQ21 targname: BARNARD-GSC-2-REF config: ^ opmode: ^ aperture: ^ sp_element: ^ num_exp: ^ time_per_exp: ^ s_to_n: ^ fluxnum_1: ^ priority: ^ param_1: ^ req_1: DO FOR TARG 34-36; comment_1: OBSERVE ONLY THOSE REFERENCE STARS comment_2: WITHIN THE ASTROMETRY PICKLE ! linenum: 25.000 sequence_1: DEFINE sequence_2: SEQ21 targname: BARNARD-GSC-1-REF config: ^ opmode: ^ aperture: ^ sp_element: ^ num_exp: ^ time_per_exp: ^ s_to_n: ^ fluxnum_1: ^ priority: ^ param_1: ^ ! linenum: 26.000 sequence_1: DEFINE sequence_2: SEQ21 targname: BARNARDS-STAR config: ^ opmode: ^ aperture: ^ sp_element: ^ num_exp: ^ time_per_exp: 10S s_to_n: ^ fluxnum_1: ^ priority: ^ param_1: ^ ! linenum: 27.000 sequence_1: USE SEQ21 req_1: AT 4 -FEB-93 +/- 4D; req_2: REPEAT 27 EVERY 16D +/- 2D FOR 16 MORE req_3: TIMES; req_4: CYCLE 2; comment_1: BREAK IN SERIES AVOIDS HST SUN comment_2: CONSTRAINTS ! ! end of exposure logsheet ! No scan data records found