! $Id: 5780,v 12.1 1995/02/03 14:31:49 pepsa Exp $ COVERPAGE: TITLE_1: The Spectrum of LMC Pulsar B0540-69; Carryover SCI_CAT: Hot Stars PROPOSAL_FOR: AUG/HSP CONT_ID: 4888 PI_FNAME: Robert PI_MI: C. PI_LNAME: Bless PI_INST: University of Wisconsin PI_COUNTRY:U.S.A. PI_PHONE: 608-262-1715 HOURS_PRI: 3.1 NUM_PRI: 1 FOS: Y ! Authorizing Institution Official: OFF_FNAME: ! First name of authorizing official, X20 OFF_LNAME: ! Last name of authorizing official, X20 OFF_TITLE: ! Title of authorizing official, X20 OFF_INST: ! Institution number OFF_ADDR_1: ! Address of authorizing official, X60 OFF_ADDR_2: ! OFF_ADDR_3: ! OFF_CITY: ! X20 OFF_STATE: ! X3 OFF_ZIP: ! X9 OFF_COUNTRY: ! X20 OFF_PHONE: ! Telephone number of authorizing official, X20 ABSTRACT: LINE_1: PSR B0540-69, a 50 ms pulsar located in the Large Magellanic LINE_2: Cloud, is the most distant pulsar known. B0540-69 is one of LINE_3: the few pulsars for which a second time derivative of LINE_4: rotational frequency has been measured. High Speed Photometer LINE_5: observations in a UV + visible passband (1600 - 7000 angstroms) LINE_6: showed a pulse profile identical to that in the X-ray region, LINE_7: with the same pulsed fraction (van Citters et al 1994). The LINE_8: rotational frequency observed by HSP, when compared with LINE_9: previous measurements, gave a value of 2.28 (0.02) for the LINE_10:braking index. B0540-69 is similar to the Crab pulsar in its LINE_11:rotational perior and associated synchrotron-emitting nebula LINE_12:(a "plerion"), but its pulse profile and braking index are LINE_13:strikingly different. We propose her to obtain an objective LINE_14:prism spectrum of B0540-69 to compare its spectral energy LINE_15:distribution in the UV and blue with that of the Crab pulsar LINE_16:and to determine the fractional part of our UV plus visible LINE_17:pulse profile due to UV photons. Our objective prism spectrum LINE_18:with the FOS Blue detector will measure the relative energy LINE_19:distribution between ~1850 and ~5000 angstroms. GENERAL_FORM_PROPOSERS: ! Replicate the section below for each investigator (PI and CoI's): LNAME: Bless FNAME: Robert MI: C. INST: Univ. of Wisc COUNTRY: U.S.A. ESA: LNAME: van Citters FNAME: G. MI: W. INST: NSF COUNTRY: U.S.A. ESA: LNAME: Dolan FNAME: Joseph MI: F. INST: NASA GSFC COUNTRY: U.S.A. ESA: LNAME: Boyd FNAME: Patricia MI: T. INST: NASA GSFC COUNTRY: U.S.A. ESA: GENERAL_FORM_ADDRESS: ! The PI's address: LNAME: Bless FNAME: Robert MI: C. CATEGORY: PI INST: ! PI's institution number, X60 ADDR_1: Univ. of Wisconsin ADDR_2: Space Astronomy Laboratory ADDR_3: 1150 University Avenue CITY: Madison STATE: WI ZIP: 53706 COUNTRY:U.S.A. PHONE: 608-262-1715 TELEX: bless@larry.sal.wisc.edu ! The address of the primary contact for this proposal (if not PI): LNAME: Dolan FNAME: Joseph MI: F. CATEGORY: CON INST: ADDR_1: NASA Goddard SFC ADDR_2: Mail Code 681 CITY: Greenbelt STATE: MD ZIP: 20707 COUNTRY:U.S.A. PHONE: 301-286-5920 TELEX: tejfd@larry.sal.wisc.edu GENERAL_FORM_TEXT: QUESTION: 3 SECTION: 1 LINE_1: We will acquire B0540-69 by first acquiring a nearby V=12.3 LINE_2: guide star catalog star, and then offsetting a known distance LINE_3: and direction to the pulsar. This method, using the measured LINE_4: offset from a WFPC early acquisiton image taken for our HSP LINE_5: program, acquired the pulsar with better than 0.5" accuracy in LINE_6: an HSP 0.32" radius aperture. No emission or absorption line LINE_7: are expected in the spectrum of Bo540-69 because the standard LINE_8: model of pulsar emission predicts the radiation is a type of LINE_9: synchrotron emission. We will obtain an objective prism LINE_10:spectrum with the FOS Blue detector to measure the realtive LINE_11:energy distribution between ~1850 and ~5000 angstroms with LINE_12:spectral resolution ranging from ~5 angstroms in the far UV to LINE_13:~220 angstroms in the blue. Assuming a power-law spectrum LINE_14:for the pulsar proportional to 1/frequency, the FOS simulator LINE_15:predicts a count rate of 0.08 counts/s diode at 2700 angstroms LINE_16:(55 angstroms/diode). A 2 hour exposure would give 575 counts/ LINE_17:diode at 2700 angstroms, or a S/N of 24. The S/N would be LINE_18:about 8 at 1850 angstroms, and about 30 at 4000 angstroms. The LINE_19:spectrum should be well exposed longward of 2200 angstroms. LINE_20:Shortward of 2200 angstroms, individual diodes can be co-added LINE_21:to give a S/N of ~ 20. At 1850 angstroms, 7 diodes can be LINE_22:co-added to give a S/N of 20 at a resolution of 35 angstroms. QUESTION: 4 SECTION: 1 LINE_1: See Phase I Proposal QUESTION: 5 SECTION: 1 LINE_1: None QUESTION: 6 SECTION: 1 LINE_1: None QUESTION: 7 SECTION: 1 LINE_1: See Phase I Proposal QUESTION: 8 SECTION: 1 LINE_1: QUESTION: 9 SECTION: 1 LINE_1: See Phase I Proposal QUESTION: 10 SECTION: 1 LINE_1: See Phase I Proposal FIXED_TARGETS: targnum: 1 name_1: B0540-69 descr_1: B,160 pos_1: RA-OFF = -4.045S +/- 0.01S, pos_2: DEC-OFF = -37.889" +/- 0.01", pos_3: FROM 2 equinox: J2000 fluxnum_1: 1 fluxval_1: V=22.7 comment_1: PULSAR IN LMC ! targnum: 2 name_1: GS-9163-462 descr_1: A,104 pos_1: RA = 5H 40M 15.448S +/- 0.01S, pos_2: DEC = -69D 19' 16.367" +/- 0.07", equinox: J2000 pm_or_par: N fluxnum_1: 1 fluxval_1: V=12.3 comment_1: OFFSET TARGET FOR LMC PULSAR ! ! end of fixed targets ! No solar system records found ! No generic target records found EXPOSURE_LOGSHEET: linenum: 1.000 targname: GS-9163-462 config: FOS/BL opmode: ACQ/PEAK aperture: 4.3 sp_element: G400H num_exp: 1 time_per_exp: 5.0S fluxnum_1: 1 priority: 1 param_1: SCAN-STEP-Y=1.204, param_2: SEARCH-SIZE-X=1, param_3: SEARCH-SIZE-Y=3, req_1: ONBOARD ACQ FOR 1.2; req_2: CYCLE 4 / 1-2; req_3: SEQ 1-2 NON-INT; ! linenum: 1.200 targname: GS-9163-462 config: FOS/BL opmode: ACQ/PEAK aperture: 1.0 sp_element: G400H num_exp: 1 time_per_exp: 6.0S fluxnum_1: 1 priority: 1 param_1: SCAN-STEP-X=0.602, param_2: SCAN-STEP-Y=0.602, param_3: SEARCH-SIZE-X=6, param_4: SEARCH-SIZE-Y=2, req_1: ONBOARD ACQ FOR 1.4; ! linenum: 1.400 targname: GS-9163-462 config: FOS/BL opmode: ACQ/PEAK aperture: 0.3 sp_element: G400H num_exp: 1 time_per_exp: 8.0S fluxnum_1: 1 priority: 1 param_1: SCAN-STEP-X=0.172, param_2: SCAN-STEP-Y=0.172, param_3: SEARCH-SIZE-X=5, param_4: SEARCH-SIZE-Y=5, req_1: ONBOARD ACQ FOR 2.0; ! linenum: 2.000 targname: B0540-69 config: FOS/BL opmode: ACCUM aperture: 1.0 sp_element: PRISM num_exp: 1 time_per_exp: 2.0H fluxnum_1: 1 priority: 1 ! ! end of exposure logsheet ! No scan data records found ! This is the end of the General Form