6485( 7) - 06/24/96 10:13 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6485 Version: 7 Check-in Date: 24-Jun-1996 10:10:37 1.Proposal Title: GHRS Observations of NGC5548 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle AGN GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: SMITA MATHUR SMITHSONIAN ASTROPHYSICAL OBSERVATORY CoI: Dr. Belinda Wilkes Smithsonian Astrophysical Observatory Y CoI: Dr. Martin Elvis Smithsonian Astrophysical Observatory N ------------------------------------------------------------------------------------ 6. Abstract We have recently identified an X-ray/UV ionized absorber in NGC5548 whose physical conditions are well-constrained. We determine a `b' value (velocity spread parameter) of ~ 40 km s^-1, significantly narrower than the measured, partially resolved CIV absorption lines (~ 350 km s^-1). In order to confirm the unification of X-ray and UV absorbers (by directly measuring the b value) and to further study the velocity structure of the probably multi-component absorber, we propose to obtain high (20 -- 40 km s^-1) resolution data around the CIV absorption line. ------------------------------------------------------------------------------------ 6485( 7) - 06/24/96 10:13 - [ 2] Observations Description ------------------------ Our goal is to resolve lines at ~ 20 to 40 km/s (R~ 15000) in the observed wavelength range of 1557 to 1587 Angstrom\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ and to reach high signal to noise (S/N of 30 per bin) (see e.g. Petitjean et al 1994). We have chosen G160M on side 2 of GHRS for this purpose. The exposure time has been calculated using the GHRS handbook. The data from two diodes will be binned together requiring S/N of 21 per diode. The last orbit will be used to do the low resolution observations with G140L on side 1. The side switching will be done during the occultation. The observed UV flux values of NGC5548 at the positions of the absorption lines are used to determine the signal. The ultraviolet spectrum of NGC5548 is variable (e.g. Korista et al 1995). The total exposure time was calculated for the smallest observed flux. Target acquisition will be done with ACQ with LSA. Total number of required orbits were calculated using the GHRS worksheet. Note that here are two previous observations of NGC5548 with the GHRS; one with G140L and one with G200M. These were, however, calibration observations for 4.8 seconds each. No science data was accumulated. Here we propose for G160M observations. Our proposed observations are NOT duplications. begincenter Table 1: GHRS Observations of NGC5548. begintabularlrccccrc &&&&&&&, Name & RA (2000) & f_Lambda^a & z & Config. & Spec. El.& Exp. & Orbits , & Dec (2000) & & & & & (min)& , &&&&&&&, NGC5548 & 14 17 59.5 & 1.0 & 0.0174 & GHRS & G160M & 215 & 6, & +25 08 12.320 & & & & & & , & & & & & G140L & 36 & 1 endtabular endcenter a. f_Lambda is in the units of 10^-13 erg s^-1 cm^- 2 AA^-1. vspace*1in Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 6485( 7) - 06/24/96 10:13 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 999 NGC5548 GALAXY,SEYFERT,RADIO RA=14H 17M 59.57S +/- J2000 Z = F(1570)=1.0e-13 QUIET,NUCLEUS, 0.04S,DEC=25D 08' 12.23" +/- 0.0174 0.6",PLATE-ID=01TM Comments: The object is variable and the flux may be different by a factor of 2 or so. 6485( 7) - 06/24/96 10:13 - [ 4] Visit: 10 Visit Requirements: On Hold Comments: Additional Comments: I would like to observe CIV absorption lines on top of the CIV emission line profile. The doublet is observed at lambda lambda 1572.4 and 1575.4 angstroms. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 11 NGC5548 HRS ACQ 2.0 MIRROR-N2 BRIGHT=RETURN,SEARCH-SIZE=3, 1 10.8 S ONBOARD ACQ FOR 20-80 LOCATE=YES Comments: STEP-TIME is 10 sec. This will generate about 900 counts. If you think I could use smaller exposure times, I would like to know. (STEP-TIME changed to 1.2S per CS review - wmw 06/12/96) ------------------------------------------------------------------------------------------------------------------------------------ 20 NGC5548 HRS ACCUM 2.0 G160M 1572 FP-SPLIT=STD 1 435.2 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NGC5548 HRS ACCUM 2.0 G160M 1572 FP-SPLIT=STD 4 544 S ------------------------------------------------------------------------------------------------------------------------------------ 40 NGC5548 HRS ACCUM 2.0 G160M 1572 FP-SPLIT=STD 4 544 S ------------------------------------------------------------------------------------------------------------------------------------ 50 NGC5548 HRS ACCUM 2.0 G160M 1572 FP-SPLIT=STD 4 544 S ------------------------------------------------------------------------------------------------------------------------------------ 60 NGC5548 HRS ACCUM 2.0 G160M 1572 FP-SPLIT=STD 4 544 S ------------------------------------------------------------------------------------------------------------------------------------ 70 NGC5548 HRS ACCUM 2.0 G160M 1572 FP-SPLIT=STD 4 544 S ------------------------------------------------------------------------------------------------------------------------------------ 72 NGC5548 HRS ACCUM 2.0 G160M 1572 FP-SPLIT=STD 5 544 S Comments: The GHRS side will be switched to 2 after this exposure. ------------------------------------------------------------------------------------------------------------------------------------ 80 NGC5548 HRS ACCUM 2.0 G140L 1572 FP-SPLIT=STD 4 544 S Comments: I could not fill in last 5 minutes of this orbit; would like to use it if possible ------------------------------------------------------------------------------------------------------------------------------------ 6485( 7) - 06/24/96 10:13 - [ 5] Summary Form for Proposal 6485 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BRIGHT=RETURN SEARCH-SIZE=3 LOCATE=YES FP-SPLIT=STD ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category AGN ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 20-80 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-N2 G160M G140L ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC5548 ------------------------------------------------------------------------------------------------------------------------------------