! File: 4635C.PROP
! Database: PEPDB
! Date: 22-FEB-1994:20:36:45
coverpage:
title_1: TESTING THE ACCRETION DISK LINE-PROFILE HYPOTHESIS IN ARP 102B:
title_2: CYCLE3MEDIUM
sci_cat: QUASARS & AGN
sci_subcat: RADIO GALAXIES
proposal_for: GO
pi_title: PROF.
pi_fname: ALEXEI
pi_mi: V.
pi_lname: FILIPPENKO
pi_inst: UC-BERKELEY
pi_country: USA
hours_pri: 7.47
num_pri: 1
fos: Y
funds_length: 12
off_fname: MARION
off_mi: B.
off_lname: LENTZ
off_title: CONT/GRANTS OFFICER
off_inst: 1500
off_addr_1: SPONSORED PROJECTS OFFICE
off_addr_2: 336 SPROUL HALL
off_addr_3: UNIVERSITY OF CALIFORNIA
off_city: BERKELEY
off_state: CA
off_zip: 94720
off_country: USA
off_phone: 510-642-8120
! end of coverpage
abstract:
line_1: Arp 102B is the prototype of a set of ten broad-line radio galaxies whose
line_2: hydrogen Balmer line profiles are double-peaked, and which share several
line_3: additional distinguishing optical characteristics. We have recently established
line_4: the reality of this class through a comprehensive optical spectroscopic survey
line_5: of radio-loud AGNs at z < 0.4 (Eracleous and Halpern 1992a,b). We now propose
line_6: to obtain moderate-resolution spectra to study the UV emission lines and
line_7: nonstellar continuum of Arp 102B. Several theories have been suggested to
line_8: explain the unusual line profiles; the most specific is a model for emission
line_9: from the photoionized atmosphere of an accretion disk. The Balmer lines are the
line_10: only broad lines detected in ground-based spectra, and the optical nucleus is
line_11: dominated by starlight. Both of these limitations restrict further progress in
line_12: understanding the nature of this peculiar spectrum. But observations of the
line_13: UV emission lines and continuum could test this model by (1) measuring line
line_14: profiles of species with different ionization potentials, and (2) measuring the
line_15: nonstellar continuum, which should be different from that of most AGNs. Disk
line_16: photoionization models predict line shapes which are different among the UV
line_17: lines. The ionizing continuum is predicted to be nonthermal, arising in an
line_18: optically thin, ion-supported torus, rather than a blackbody accretion disk.
line_19: If supported by the results of HST spectra, our study of Arp 102B could
line_20: provide the most direct view of an accretion disk in an AGN.
!
! end of abstract
general_form_proposers:
lname: FILIPPENKO
fname: ALEXEI
title: PI
mi: V.
inst: UC-BERKELEY
country: USA
!
lname: HALPERN
fname: JULES
mi: P.
inst: COLUMBIA UNIVERSITY
country: USA
!
lname: CHEN
fname: KAIYOU
inst: LOS ALAMOS NATIONAL LAB
country: USA
!
lname: ERACLEOUS
fname: MICHAEL
mi: C.
inst: COLUMBIA UNIVERSITY
country: USA
!
! end of general_form_proposers block
general_form_text:
question: 3
section: 1
line_1: To detect faint lines, to model in detail the profiles of broad lines, and to
line_2: determine the overall shape of the continuum, we require spectra having good
line_3: S/N ratio and modest resolution over the entire accessible UV wavelength range.
line_4: We will connect the red end of the UV spectrum (around 3150 A) with our optical
line_5: spectra, obtained at ground-based observatories. This will give a reliable
line_6: continuum shape over the range 1150-10000 A, and it will allow us to obtain
line_7: accurate emission-line intensity ratios between UV and optical lines. Three HST
line_8: grating settings are needed, as follows:
line_9: (1) FOS, G130H grating, 1150-1608 A, 1.0 A/diode, blue digicon.
line_10: (2) FOS, G190H grating, 1573-2323 A, 1.5 A/diode, red digicon.
line_11: (3) FOS, G270H grating, 2227-3306 A, 2.1 A/diode, red digicon.
line_12: The FOS spectra will be obtained through the 4.3" X 4.3" aperture (effectively
line_13: 4.3" X 1.4", due to diode size). This yields the best throughput, and the
line_14: resulting resolution will be adequate for our purposes. At UV wavelengths,
line_15: the starlight contamination through this aperture will be small compared with
line_16: light from the active nucleus. Thus, the spherical aberration of HST does
line_17: not affect us very much (except for the broad wings on the line profile).
line_18: The first setting above gives us Ly-alpha and C IV 1549, two very important
line_19: lines. Most of the Ly-alpha profile will be redshifted away from the geocoronal
line_20: emission. The second setting includes He II 1640 and C III] 1909, while the
line_21: most important lines in the third setting are C II] 2326, [Ne IV] 2423, and
line_22: Mg II 2800. We might also detect Fe II blends. Together, these grating settings
line_23: will allow us to determine whether there is a UV bump in the continuum.
!
question: 4
section: 1
line_1: Until now, the hydrogen lines are the only broad lines which have been seen in
line_2: Arp 102B. IUE observations of Arp 102B have resulted in weak detections of
line_3: continuum and Ly-alpha. SWP and LWP exposures of duration 265 and 120 minutes,
line_4: respectively, barely detected continuum in the 1600-3000 A range (Chen
line_5: et al. 1989), consistent with an extrapolation of the optical continuum. The
line_6: only UV emission line detected by IUE was Ly-alpha, but the resolution and
line_7: S/N ratio are low. Its velocity width appears to be much less than that of
line_8: the Balmer lines, a very suggestive result. On the other hand, at least half
line_9: of the Ly-alpha flux could be coming from the narrow-line region, which would
line_10: be consistent with typical narrow-line ratios. We must obtain a much better
line_11: profile and a more accurate measurement the continuum shape if meaningful
line_12: conclusions about the origin of the emission lines are to be drawn. Other,
line_13: weaker UV lines must also be studied. HST is the only telescope that can
line_14: provide the necessary data on the emission lines and nonstellar continuum.
line_15: These data will test the theory of the origin of emission lines in a
line_16: photoionized disk atmosphere. If the theory survives the observations, physical
line_17: properties such as ionization parameter and density in the photoionized disk
line_18: atmosphere could be estimated for the first time in an AGN accretion disk.
line_19: An important supporting piece of data that will aid in the interpretation
line_20: of the ionizing continuum is the soft X-ray spectrum. X-ray observations
line_21: of Arp 102B have already been obtained with the ROSAT PSPC, and will be
line_22: available for archival analysis by the time the HST observations are made.
!
question: 4
section: 2
line_1: From the IUE data of Chen et al. (1989), we estimate that the observed
line_2: continuum flux density of Arp 102B at 1400 A, 1700 A, and 2300 A is 0.05 mJy,
line_3: 0.10 mJy, and 0.18 mJy, respectively.
line_4: FOS, G130H grating, blue digicon: At 1400 A, the efficiency is 0.007. The
line_5: throughput of the 4.3" X 4.3" aperture is 0.47 for point sources, and we have
line_6: 1.0 A/diode. Using equation (5) of Table 1.2.1 in the FOS Instrument Handbook,
line_7: we find a count rate of 0.008 per second per diode. Zodiacal light, airglow,
line_8: and diffuse Galactic light will not significantly affect our observations.
line_9: The dark current is comparable to the expected signal; thus, the exposure time
line_10: must be doubled to achieve the desired S/N ratio, compared with the case of
line_11: negligible dark current. Rebinning the data to 2 A/bin, we therefore require
line_12: 242 minutes for S/N = 11 in the continuum at 1400 A.
line_13: FOS, G190H grating, red digicon: At 1700 A, the efficiency is 0.02. The
line_14: throughput of the 4.3" X 4.3" aperture is 0.52, and we have 1.47 A/diode.
line_15: The derived count rate is 0.06 per second per diode in the continuum.
line_16: Background sky and dark current are negligible; thus, the integration time is
line_17: equal to (S/N)**2/count-rate. For S/N = 23, we require 143 minutes.
line_18: FOS, G270H grating, red digicon: At 2300 A, the efficiency is 0.06. The
line_19: point-source throughput is 0.55, and there are 2.09 A/diode. The derived
line_20: continuum count rate is 0.37 per second per diode. Sky and dark current are
line_21: entirely negligible. For S/N = 36, we require 60 minutes.
line_22: Please add 18M to G130H (total = 260M) and 3M to G190H (total = 146M) if the
line_23: extra time needed for ACQ/PEAK is not charged to the GO (see Question 5).
!
question: 5
section: 1
line_1: Originally I had assumed that ACQ/BINARY would be used to acquire the
line_2: target. However, during a visit to STScI I was told this would be quite risky
line_3: for a galaxy, even though it has a star-like nucleus (it is an active galaxy).
line_4: The reason is that the background is uneven, and also the apparent brightness
line_5: depends on how much of the "fuzz" is integrated. Moreover, the nucleus itself
line_6: might even be resolved on the 0.3" scale. So, I reluctantly decided to play
line_7: it safe and use ACQ/PEAK instead. Since the total spacecraft time exceeds
line_8: 6 hours, the peak-up has to be done for the blue and red sides separately
line_9: (i.e., side-switching is not allowed). I have put relatively long integration
line_10: times for the dwells, in order to be certain of getting enough counts for
line_11: successful acquisition. The first spatial scan will be 3 X 1 with the 4.3"
line_12: aperture; each dwell should be 1 s on the red side, and 8 s on the blue side.
line_13: The second spatial scan will be 2 X 6 with the 1" circular aperture; each
line_14: dwell should be 2 s on the red side, and 12 s on the blue side. (The object
line_15: is quite red.) The science observations will be conducted with the 4.3"
line_16: aperture.
line_17: If it turns out that the extra time for peak-up acquisitions is NOT
line_18: charged to the GO, please ADD 18M (total = 260M) to the FOS/BL G130H science
line_19: integration (exposure line 7), and ADD 3M (total = 146M) to the FOS/RD G190H
line_20: integration (exposure line 4). This will make the total time equal to
line_21: the allocated spacecraft time, if ACQ/BINARY had been used. Thank you.
!
question: 6
section: 1
line_1: None.
!
question: 7
section: 1
line_1: Measurement and analysis of the calibrated one-dimensional spectra will be
line_2: done with an extensive program written by the PI for his studies of optical
line_3: spectra. All emission lines will be measured (wavelengths, fluxes, equivalent
line_4: widths, velocity widths), and the continuum shape will be determined.
line_5: We will fit accretion disk line profiles to each broad emission line; the
line_6: variation of line emissivity with radius will be parametrized as a power-law
line_7: index. Alternatively, direct deconvolution techniques can be used to derive
line_8: the emissivity as a function of radius, without reference to an analytic form
line_9: Direct comparison with detailed photoionization predictions for the line
line_10: profiles can also be made. Comparisons of the derived radii for different
line_11: lines can be used to search for stratification into zones of different
line_12: ionization potential. The fit to the power-law emissivity index will yield
line_13: information about the geometry and extent of the ionizing source.
line_14: The UV-optical nonstellar continuum of Arp 102B will be compared with that
line_15: of other AGNs to look for similarities (e.g., UV bump and/or power law) and
line_16: differences. Perhaps a new type of spectrum, possibly attributable to the
line_17: hypothesized ion torus, will be found. There will also be information about
line_18: the soft X-ray/EUV spectrum from archival ROSAT observations that have already
line_19: been obtained, so that a better description of the ionizing continuum can be
line_20: made. These data will be used in a more accurate analysis of the energy budget
line_21: of the photoionized disk atmosphere. A true photoionization model which
line_22: incorporates the geometries of the disk and ionizing source will be attempted
line_23: with the observed and extrapolated ionizing spectrum.
!
question: 8
section: 1
line_1: When our HST observing dates become known, we will request nearly simultaneous
line_2: time at Lick and Keck Observatories to obtain optical spectra and images, IR
line_3: images, and IR spectra. These data will be combined with the UV spectra to
line_4: construct an overall continuum spanning a large wavelength range. A complete
line_5: analysis of the data will subsequently be done. No funds are being requested
line_6: here to support the ground-based observations.
!
question: 9
section: 1
line_1: A. V. Filippenko, PI: GO 2590, "Deep Imaging of the Site of SN 1961V, a
line_2: Possible Extragalactic Eta Carinae Analogue." Not related to this project.
line_3: A. V. Filippenko, Co-I: GO 3484, "Probing the Nuclear Regions of the
line_4: Seyfert Galaxy NGC 5548." (PI: B. M. Peterson). Not related to this project.
line_5: A. V. Filippenko, PI: GO 3507, "UV Spectroscopy and High-Resolution Imaging
line_6: of NGC 4395, the Least Luminous and Nearest Known Seyfert 1 Nucleus."
line_7: Not related to this project, but shows that the data quality for Arp 102B
line_8: should be adequate. (NGC 4395 is comparable to Arp 102B in UV brightness.)
line_9: A. V. Filippenko, Co-I: GO 3519, "UV Imaging of Nearby Galaxies."
line_10: (PI: D. Maoz.) Not related to this project.
line_11: A. V. Filippenko, Co-I: GO 3810, "The Stellar Content of Wolf-Rayet
line_12: Galaxies." (PI: P. Conti.) Not related to this project.
line_13: In addition, Filippenko was involved in one of the discoveries made by
line_14: the QSO Snapshot Survey (PI: J. N. Bahcall.)
!
question: 9
section: 2
line_1: GO 2590: Data were received a few months ago, and are currently being
line_2: analyzed. An object has been detected at the position of SN 1961V; color
line_3: information is being used to determine whether this is the supernova
line_4: remnant, the surviving "progenitor," or an unrelated object.
line_5: GO 3507: We recently received the data. Preliminary analysis reveals
line_6: strong emission lines similar to those of luminous Seyfert 1 nuclei (e.g.,
line_7: C IV 1549, C III] 1909, Mg II 2800) superposed on a weak continuum. The
line_8: nucleus seems unresolved on a scale of 1 pc (0.1"). Thus, NGC 4395 appears
line_9: to contain a bona fide Seyfert 1 nucleus, but with an absolute blue magnitude
line_10: of only -10 --- comparable to very luminous stars
line_11: Other proposals: Data not obtained yet.
!
question: 9
section: 3
line_1: "A Gravitational Lens Candidate Discovered with the Hubble Space
line_2: Telescope." D. Maoz, J. N. Bahcall, D. P. Schneider, R. Doxsey, N. A.
line_3: Bahcall, A. V. Filippenko, W. M. Goss, O. Lahav, and B. Yanny;
line_4: Astrophysical Journal (Letters), 386, L1, 1992.
!
question: 10
section: 1
line_1: Both U. C. Berkeley and Columbia University have extensive computing facilities
line_2: (VMS and UNIX) in their Astronomy Departments, as does Los Alamos National
line_3: Laboratory. Image-processing workstations, graphics terminals, laser printers,
line_4: large disks, and tape drives are all available. Many computer programs exist
line_5: for analysis of data. Both universities also have many highly capable graduate
line_6: students and postdoctoral fellows, some of whom may participate in various
line_7: aspects of this project. Ground-based complementary observations can readily be
line_8: obtained (with short notice) at Lick Observatory; proposals for Keck time will
line_9: also be submitted by the PI. The usual secretarial and technical support is
line_10: available at Berkeley, Columbia, and Los Alamos.
!
!end of general form text
general_form_address:
lname: FILIPPENKO
fname: ALEXEI
mi: V.
title: PROF.
category: PI
inst: UC-Berkeley
addr_1: DEPARTMENT OF ASTRONOMY
addr_2: 601 CAMPBELL HALL
addr_3: UNIVERSITY OF CALIFORNIA
city: BERKELEY
state: CA
zip: 94720
country: USA
phone: 510-642-1813
!
! end of general_form_address records
fixed_targets:
targnum: 1
name_1: ARP102B
descr_1: E,303,315,320,910
pos_1: RA = 17H 17M 56.34S +/- 0.04S,
pos_2: DEC = +49D 01' 49.6" +/- 0.6"
equinox: 1950.0
rv_or_z: Z = 0.02438
comment_1: MAGNITUDES AND FLUXES
comment_2: REFER TO NUCLEUS ONLY.
comment_3: BRIGHT NUCLEUS SUPERPOSED ON
comment_4: FAINTER GALAXY BACKGROUND.
comment_5: PI HAS COMPARED THESE COORDS TO
comment_6: GASP, AND PREFERS THESE. - 2/11/93
fluxnum_1: 1
fluxval_1: V = 16.0 +/- 0.3
fluxnum_2: 2
fluxval_2: B-V = 1.0 +/- 0.2
fluxnum_3: 3
fluxval_3: F-CONT(1400) = 7.6 +/- 2.3 E-16
fluxnum_4: 4
fluxval_4: F-CONT(1700) = 1.0 +/- 0.3 E-15
fluxnum_5: 5
fluxval_5: F-CONT(2300) = 1.0 +/- 0.3 E-15
!
! end of fixed targets
! No solar system records found
! No generic target records found
exposure_logsheet:
linenum: 1.000
targname: ARP102B
config: FOS/RD
opmode: ACQ/PEAK
aperture: 4.3
sp_element: MIRROR
num_exp: 1
time_per_exp: 1S
fluxnum_1: 1
fluxnum_2: 2
priority: 1
req_1: ONBOARD ACQ FOR 2;
req_2: SPATIAL SCAN;
req_3: CYCLE 3 / 1-7;
req_4: GROUP 1-4 NO GAP;
!
linenum: 2.000
targname: ARP102B
config: FOS/RD
opmode: ACQ/PEAK
aperture: 1.0
sp_element: MIRROR
num_exp: 1
time_per_exp: 2S
fluxnum_1: 1
fluxnum_2: 2
priority: 1
req_1: ONBOARD ACQ FOR 3-4;
req_2: SPATIAL SCAN;
!
linenum: 3.000
targname: ARP102B
config: FOS/RD
opmode: ACCUM
aperture: 4.3
sp_element: G270H
wavelength: 2760
num_exp: 1
time_per_exp: 60M
s_to_n: 36
fluxnum_1: 5
priority: 1
comment_1: IF THERE IS EXTRA TIME BEFORE
comment_2: EARTH OCCULTATION NEAR END OF
comment_3: EXPOSURE, CAN INCREASE EXPOSURE
comment_4: TIME TO INCREASE S/N RATIO.
!
linenum: 4.000
targname: ARP102B
config: FOS/RD
opmode: ACCUM
aperture: 4.3
sp_element: G190H
wavelength: 1950
num_exp: 1
time_per_exp: 143M
s_to_n: 23
fluxnum_1: 4
priority: 2
comment_1: IF THERE IS EXTRA TIME BEFORE
comment_2: EARTH OCCULTATION NEAR END OF
comment_3: EXPOSURE, CAN INCREASE EXPOSURE
comment_4: TIME TO INCREASE S/N RATIO.
!
linenum: 5.000
targname: ARP102B
config: FOS/BL
opmode: ACQ/PEAK
aperture: 4.3
sp_element: MIRROR
num_exp: 1
time_per_exp: 8S
fluxnum_1: 1
fluxnum_2: 2
priority: 3
req_1: ONBOARD ACQ FOR 6;
req_2: SPATIAL SCAN;
req_3: GROUP 5-7 NO GAP;
!
linenum: 6.000
targname: ARP102B
config: FOS/BL
opmode: ACQ/PEAK
aperture: 1.0
sp_element: MIRROR
num_exp: 1
time_per_exp: 12S
fluxnum_1: 1
fluxnum_2: 2
priority: 3
req_1: ONBOARD ACQ FOR 7;
req_2: SPATIAL SCAN;
!
linenum: 7.000
targname: ARP102B
config: FOS/BL
opmode: ACCUM
aperture: 4.3
sp_element: G130H
wavelength: 1380
num_exp: 1
time_per_exp: 242M
s_to_n: 11
fluxnum_1: 3
priority: 3
comment_1: IF THERE IS EXTRA TIME BEFORE
comment_2: EARTH OCCULTATION NEAR END OF
comment_3: EXPOSURE, CAN INCREASE EXPOSURE
comment_4: TIME TO INCREASE S/N RATIO.
!
! end of exposure logsheet
scan_data:
line_list: 1,5
fgs_scan:
cont_dwell: D
dwell_pnts: 3
dwell_secs: 1.00
scan_width: 0.0000
scan_length: 2.8000
sides_angle: 90.0000
number_lines: 1
scan_rate: 0.0000
first_line_pa: 0.0000
scan_frame: S/C
len_offset: 1.4000
wid_offset: 0.0000
!
line_list: 2,6
fgs_scan:
cont_dwell: D
dwell_pnts: 6
dwell_secs: 1.00
scan_width: 0.7000
scan_length: 3.5000
sides_angle: 90.0000
number_lines: 2
scan_rate: 0.0000
first_line_pa: 90.0000
scan_frame: S/C
len_offset: 1.7500
wid_offset: 0.3500
!
! end of scan data