6704( 12) - 03/28/96 15:30 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6704 Version: 12 Check-in Date: 28-Mar-1996 15:26:32 1.Proposal Title: Dust in the Broad-Line Regions of Seyfert Galaxies ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle AGN GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Robert Goodrich Space Telescope Science Institute CoI: Anuradha Koratkar Space Telescope Science Institute N CoI: Michael Eracleous University of California, Berkeley N ------------------------------------------------------------------------------------ 6. Abstract The classes of objects called Seyfert 1.8 and Seyfert 1.9 galaxies show weak broad Balmer lines and a weak nonstellar continuum. Two theories have been proposed to explain their characteristics: (1) dust along the line of sight to the broad -line region (BLR) and the continuum reddens and weakens the nuclear spectrum, and (2) low optical depth and low ionization parameter in the BLR, which has been shown to give large Balmer decrements. These competing theories can be critically tested by observing both LyAlpha and HAlpha and comparing their strengths. In the reddening hypothesis LyAlpha should be reduced by a factor of ~ 10^-4 from its intrinsic value, while in the other hypothesis the LyAlpha/HAlpha ratio should be similar to that seen in Seyfert 1 galaxies. We will use the GHRS and ground-based spectroscopy to obtain nearly simultaneous LyAlpha and HAlpha spectra of eight Seyfert 1.8 and 1.9 galaxies. This will provide a clear and unambiguous test of the two theories discussed above. ------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 2] Observations Description ------------------------ The primary goal of the project is to measure LyAlpha lines in eight Seyfert 1.8 and 1.9 galaxies using the GHRS and the G140L grating. At LyAlpha the GHRS is several times more sensitive than the FOS. While sensitivity measurements of STIS are not yet available, preliminary estimates from New Instruments for Second Servicing Mission indicate that it will not be greatly higher in sensitivity than GHRS at LyAlpha. Since our project does not require any of the unique capabilities of STIS, such as long-slit coverage, or large wavelength coverage, and since we obtain adequate data with one orbit per target using the GHRS, there is no reason to postpone this project until STIS becomes available. As a sample exposure calculation we assume the following: (a) a broad HAlpha flux of 100 * 10^-15 erg cm^-2 s^-1, (b) a LyAlpha/HAlpha ratio of 3, (c) a line width of 5000 km s^-1, and (d) a redshift of 0.04. These parameters are close to the actual parameters of, e.g., Mrk 883, and are typical of our targets, all of which are listed in Table 1. The line width corresponds to 21 Angstrom = 37 diodes. The sensitivity of the instrument is 150 * 10^11 ct s^-1 diode^-1 per incident erg cm^-2 s^-1 AA^-1, leading to an average count rate of 0.21 ct s^-1 diode^-1. This is well above the dark count of 0.008 ct s^-1 diode^-1, which we can safely ignore. The total count rate in LyAlpha is 7.9 ct s^-1, yielding ~ 14,000 total counts in a 30-minute exposure. The optical continuum flux in Seyfert 1.8s and 1.9s is lower than is typical for Seyfert 1 galaxies, and little is known about their UV continua. However, since broad LyAlpha dominates the continuum in Seyfert 1s, it seems safe to ignore the continuum noise in the above calculation. Our targets will be acquired by the FOS, the usual procedure for observing faint objects with the GHRS. After an 8- minute guide star acquisition we will require a 9 minute binary acquisition with the FOS/BL side, allowing ~ 35 minutes for the GHRS exposure. This will allow us to reach a limiting sensitivity of 10^-14 erg cm^-2 s^-1, perfectly adequate for our project. Real Time Justification ----------------------- None. When the appropriate application deadlines arrive we will propose to one or two ground-based optical telescopes for supporting optical spectroscopy. They key here is to get good HAlpha line fluxes at nearly the same time as the GHRS LyAlpha spectroscopy. The Lick spectrographs we plan to use allow coverage of HBeta as well as HAlpha. Goodrich (1995) used the 1.5-m Palomar reflector to produce high-quality spectra in one or two-hour exposures. Calibration Justification ------------------------- Additional Comments ------------------- Instead of ground-based H-alpha spectroscopy we can instead take a quick (~5 minute) exposure with the FOS/RD and G780H grating, since we are performing FOS -assisted acquisitions anyway. However, we must check whether we can find a guide star or guide stars available which is visible when the target is centered in both the FOS/RD and GHRS apertures. The area of overlap in the FGS pickles is roughly 50% of the total FGS area, so this is not an unreasonable hope. We must check each object individually, however, to be sure. Obtaining H- alpha and Ly-alpha in the same orbit has two added advantages over obtaining H- alpha separately from the ground. First, scheduling ground-based observations within a couple of months of the HST observations is all that can be hoped for, rather than within minutes as using FOS/RD will achieve. Secondly, the superior spatial resolution of HST will produce a spectrum with much less starlight contamination than a ground-based spectrum would have, making the broad H-alpha flux measurement more accurate. ------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 3] Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 MRK1018 GALAXY,SEYFERT, RA=02H 06M 16.01S +/- 0.5", DEC= J2000 Z = F(4500)=2.3e-15 -00D 17' 29.6" +/- 0.5", PLATE- 0.04237 F(6800)=1.3e-15 ID=0086 V = 15.75+/-0.15 B-V = 0.00+/-0.15 E(B-V) = 0.00 F-LINE(6563)=412+/-80e-15 W-LINE(6563)=100+/-20 Comments: The continuum fluxes at 4500 and 6800 are starlight- subtracted, and are what we used to estimate BIN/ACQ exposures, using starmag=15.75, power=0.62. We do *not* use the V and B-V magnitudes, since they are integrated over the whole galaxy profile, and are starlight-dominated. 2 NGC2622 GALAXY,SEYFERT, RA=08H 38M 10.98S +/- 0.5", J2000 Z = F(4500)=1.16e-15 DEC=+24D 53' 43.0" +/- 0.5", 0.02851 F(6800)=1.22e-15 PLATE-ID=0388 B = 16.20+/-0.19 E(B-V) = 0.01 F-LINE(6563)=451+/-90e-15 W-LINE(6563)=100+/-20 Comments: The continuum fluxes at 4500 and 6800 are starlight- subtracted, and are what we used to estimate BIN/ACQ exposures, using starmag=16.2, power=2.12. 3 MRK728 GALAXY,SEYFERT, RA=11H 01M 01.78S +/- 0.5", J2000 Z = F(4500)=0.27e-15 DEC=+11D 02' 48.4" +/- 0.5", 0.03565 F(7400)=0.3e-15 PLATE-ID=0258 V = 17.7+/-0.02 B-V = -0.63+/-0.60 E(B-V) = 0.00 F-LINE(6563)=164+/-30e-15 W-LINE(6563)=100+/-20 Comments: The continuum fluxes at 4500 and 7400 are starlight- subtracted, and are what we used to estimate BIN/ACQ exposures, using starmag=17.7, power=2.21. 4 MRK423 GALAXY,SEYFERT, RA=11H 26M 48.52S +/- 0.5", J2000 Z = F(4500)=1.65e-15 DEC=+35D 15' 03.1" +/- 0.5", 0.03217 F(7400)=1.25e-15 PLATE-ID=01PU V = 15.95+/-0.02 B-V = 0.49 E(B-V) = 0.00 F-LINE(6563)=188+/-40e-15 W-LINE(6563)=100+/-20 Comments: The continuum fluxes at 4500 and 7400 are starlight- subtracted, and are what we used to estimate BIN/ACQ exposures, using starmag=15.95, power=1.44. 6704( 12) - 03/28/96 15:30 - [ 5] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 5 NGC3786 GALAXY,SEYFERT, RA=11H 39M 42.57S +/- 0.5", J2000 Z = F(4500)=16.8e-15 DEC=+31D 54' 33.4" +/- 0.5", 0.00891 F(6800)=1.05e-15 PLATE-ID=01TE V = 13.6+/-0.02 B-V = -0.50+/-0.18 E(B-V) = 0.00 F-LINE(6563)=1080+/-40e-15 W-LINE(6563)=100+/-20 Comments: These are *not* starlight-subtracted, and to account for this we increased the estimated BIN/ACQ exposure times by a factor of two. The parameters used were starmag=13.6, power=0.86 (before increasing the exposure by x2). 6 UGC7064 GALAXY,SEYFERT, RA=12H 04M 43.36S +/- 2", J2000 Z = F(4500)=1.45e-15 DEC=+31D 10' 38.1" +/- 2", PLATE 0.02498 F(6800)=1.05e-15 -ID=00DJ B = 16.1+/-0.19 E(B-V) = 0.00 F-LINE(6563)=78+/-15e-15 W-LINE(6563)=100+/-20 Comments: The continuum fluxes at 4500 and 6800 are starlight- subtracted, and are what we used to estimate BIN/ACQ exposures, using starmag=16.1, power=1.22. 7 MRK883 GALAXY,SEYFERT, RA=16H 29M 52.85S +/- 0.5", J2000 Z = F(4500)=1.2e-15 DEC=+24D 26' 38.2" +/- 0.5", 0.03750 F(6800)=0.7e-15 PLATE-ID=02BA V = 16.5+/-0.2 E(B-V) = 0.03 F-LINE(6563)=187+/-40e-15 W-LINE(6563)=100+/-20 Comments: The continuum fluxes at 4500 and 6800 are starlight- subtracted, and are what we used to estimate BIN/ACQ exposures, using starmag=16.5, power=0.69. 8 MRK516 GALAXY,SEYFERT, RA=21H 56M 22.26S +/- 0.5", J2000 Z = F(4800)=0.55e-15 DEC=+07D 22' 00.4" +/- 0.5", 0.02913 F(6800)=0.5e-15 PLATE-ID=02BV B = 17.1+/-0.3 E(B-V) = 0.04 F-LINE(6563)=32+/-6e-15 W-LINE(6563)=100+/-20 Comments: The continuum fluxes at 4800 and 6800 are starlight- subtracted, and are what we used to estimate BIN/ACQ exposures, using starmag=17.1, power=1.73. 6704( 12) - 03/28/96 15:30 - [ 6] Visit: 01 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 MRK1018 FOS/RD ACQ/BIN 4.3 MIRROR 1 4S ONBOARD ACQ FOR 2-3 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 MRK1018 FOS/RD ACCUM 1.0 G780H 1 240S MAX DUR 100% Comments: H-alpha exposure ------------------------------------------------------------------------------------------------------------------------------------ 3 MRK1018 HRS ACCUM 2.0 G140L 1290 1 1033.6S Comments: Ly-alpha exposure. Note that the 9M charged to acquiring a new GS for the HRS is a bug...this will actucally go into the HRS exposure. REQUIRES manual merge in TRANS ------------------------------------------------------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 7] Visit: 02 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC2622 FOS/RD ACQ/BIN 4.3 MIRROR 1 10S ONBOARD ACQ FOR 2-3 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC2622 FOS/RD ACCUM 1.0 G780H 1 240S MAX DUR 100% Comments: H-alpha exposure ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC2622 HRS ACCUM 2.0 G140L 1290 1 1033.6S Comments: Ly-alpha exposure. Note that the 9M charged to acquiring a new GS for the HRS is a bug...this will actucally go into the HRS exposure. REQUIRES manual merge in TRANS ------------------------------------------------------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 8] Visit: 03 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 MRK728 FOS/RD ACQ/BIN 4.3 MIRROR 1 36S ONBOARD ACQ FOR 2-3 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 MRK728 FOS/RD ACCUM 1.0 G780H 1 240S MAX DUR 100% Comments: H-alpha exposure ------------------------------------------------------------------------------------------------------------------------------------ 3 MRK728 HRS ACCUM 2.0 G140L 1290 1 924.8S Comments: Ly-alpha exposure. Note that the 9M charged to acquiring a new GS for the HRS is a bug...this will actucally go into the HRS exposure. REQUIRES manual merge in TRANS. ------------------------------------------------------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 9] Visit: 04 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 MRK423 FOS/RD ACQ/BIN 4.3 MIRROR 1 6S ONBOARD ACQ FOR 2-3 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 MRK423 FOS/RD ACCUM 1.0 G780H 1 240S MAX DUR 100% Comments: H-alpha exposure ------------------------------------------------------------------------------------------------------------------------------------ 3 MRK423 HRS ACCUM 2.0 G140L 1290 1 1033.6S Comments: Ly-alpha exposure. Note that the 9M charged to acquiring a new GS for the HRS is a bug...this will actucally go into the HRS exposure. REQUIRES manual merge in TRANS. ------------------------------------------------------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 10] Visit: 05 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC3786 FOS/RD ACQ/BIN 4.3 MIRROR 1 1S ONBOARD ACQ FOR 2-3 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC3786 FOS/RD ACCUM 1.0 G780H 1 240S MAX DUR 100% Comments: H-alpha exposure ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC3786 HRS ACCUM 2.0 G140L 1290 1 1060.8S Comments: Ly-alpha exposure. Note that the 9M charged to acquiring a new GS for the HRS is a bug...this will actucally go into the HRS exposure. REQUIRES manual merge in TRANS. ------------------------------------------------------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 11] Visit: 06 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 UGC7064 FOS/RD ACQ/BIN 4.3 MIRROR 1 6S ONBOARD ACQ FOR 2-3 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 UGC7064 FOS/RD ACCUM 1.0 G780H 1 240S MAX DUR 100% Comments: H-alpha exposure ------------------------------------------------------------------------------------------------------------------------------------ 3 UGC7064 HRS ACCUM 2.0 G140L 1290 1 1060.8S Comments: Ly-alpha exposure. Note that the 9M charged to acquiring a new GS for the HRS is a bug...this will actucally go into the HRS exposure. REQUIRES manual merge in TRANS. ------------------------------------------------------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 12] Visit: 07 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 MRK883 FOS/RD ACQ/BIN 4.3 MIRROR 1 7S ONBOARD ACQ FOR 2-3 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 MRK883 FOS/RD ACCUM 1.0 G780H 1 240S MAX DUR 100% Comments: H-alpha exposure ------------------------------------------------------------------------------------------------------------------------------------ 3 MRK883 HRS ACCUM 2.0 G140L 1290 1 1033.6S Comments: Ly-alpha exposure. Note that the 9M charged to acquiring a new GS for the HRS is a bug...this will actucally go into the HRS exposure. REQUIRES manual merge in TRANS. ------------------------------------------------------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 13] Visit: 08 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 MRK516 FOS/RD ACQ/BIN 4.3 MIRROR 1 18S ONBOARD ACQ FOR 2-3 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 MRK516 FOS/RD ACCUM 1.0 G780H 1 240S MAX DUR 100% Comments: H-alpha exposure ------------------------------------------------------------------------------------------------------------------------------------ 3 MRK516 HRS ACCUM 2.0 G140L 1290 1 924.8S Comments: Ly-alpha exposure. Note that the 9M charged to acquiring a new GS for the HRS is a bug...this will actucally go into the HRS exposure. REQUIRES manual merge in TRANS. ------------------------------------------------------------------------------------------------------------------------------------ 6704( 12) - 03/28/96 15:30 - [ 14] Summary Form for Proposal 6704 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/RD HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category AGN ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 2-3 MAX DUR 100% ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G780H G140L ------------------------------------------------------------------------------------------------------------------------------------ Target Names MRK1018 NGC2622 MRK728 MRK423 NGC3786 UGC7064 MRK883 MRK516 ------------------------------------------------------------------------------------------------------------------------------------