! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal Template
! Id: 6112
!
! For help call your Program Coordinator: Max Mutchler
! Phone: 410 338-1321, E-mail: mutchler@stsci.edu
Proposal_Information
Title: UV-Bright LINERs and the AGN Connection
Proposal_Category: GO
Scientific_Category: AGN
Cycle: 5
Investigators
PI_name: Dan Maoz
PI_Institution: Tel-Aviv University
CoI_Name: A. V. Filippenko
CoI_Institution: University of California, Berkeley
Contact:
CoI_Name: Luis C. Ho
CoI_Institution: University of California, Berkeley
Contact:
CoI_Name: Joseph C. Shields
CoI_Institution: University of Arizona
Contact:
CoI_Name: A. Koratkar
CoI_Institution: Space Telescope Science Institute
Contact:
Abstract: ! Free format text (please update)
We propose UV spectroscopy of two LINER galaxies displaying
bright compact ultraviolet nuclear sources in HST FOC images.
Together with two additional objects already being observed in
Cycle 4, these are two of the four LINERs that were detected as
nuclear UV sources in a complete sample of over 100 nearby
galaxies imaged with HST. They may be the subgroup of LINERs
in which the ionizing continuum is unobscured along our line
of sight. As such, they are prime targets for studying the UV
properties of LINERs and relating them to AGNs as a whole. We
will measure the continuum shapes, emission-line fluxes and
absorption-line features of UV-bright LINERs. With these
measurements, we will discriminate between the excitation
mechanisms that have been proposed for LINERs. In particular,
we will test whether the observed UV sources are the weakest
manifestation of the quasar phenomenon, or else a compact
young stellar cluster. Placing LINERS (which exist in a large
fraction of all galaxies) into, or removing them from the AGN
zoo is important for understanding the nature of AGNs, their
number and evolution, and their contribution to the X-ray
background. Together with ASCA and ISO data and existing
optical spectra, HST will provide for the first time a
multiwavelength picture of a statistical sample of LINERs
which will be instrumental for deciphering their nature.
Questions ! Free format text (please update)
Observing_Description:
We will observe each of the two UV-bright LINERs through
three FOS gratings, G130H, G190H, and G270H, in order to
cover the 1150--3300 Angstrom range at 1-2 Angstrom (200-250
km/s) resolution. This will allow resolving and measuring line
-widths for some of the emission lines, especially in the
objects with broader lines. We will use the 0.86'' (1.0)
circular aperture. Based on the FOC images, we know the
sources are unresolved and the extended galaxy background
negligible at UV wavelengths. The large aperture will
therefore not degrade the spectral resolution. By using the
0.86'' aperture we will gain by maximizing the throughput,
and by being able to switch to the FOS/RD for the G190H and
G270H gratings to increase the efficiency without requiring a
new peakup acquisition. At ~ 3200Angstrom, where the
starlight from the underlying galaxy begins to dominate, the
0.86'' aperture will provide a fairly good match to our
ground-based 1''-aperture optical spectra of these objects.
Additional diffuse and point-sources which we have identified
in the FOC images around the bright central sources are
always >0.65'' away from the central sources, and so will be
nicely excluded by the 0.43''-radius aperture. From our FOC
data, we have accurate measurements of the broad-band (~
2300Angstrom) UV flux in each of the LINERs, with
f_Lambda(2270A) of (1 and 10) * 10^-15 erg s^-1cm^-2 A^-2 for
NGC 5055 and NGC 4569, respectively.
Assuming LINERs have a f_Nu\propto nu^-1
continuum like other low-luminosity AGNs, we can obtain a
good estimate of the expected flux. For NGC 5055 (Dec. +42)
we have 54-minutes visibility per orbit, allowing an A+B1+D1
peakup acquisition in one orbit (12 min GS acquisition, + 42
min A+B1+D1 = 54 minutes). Allowing for 6 minutes reacq time
and 7 minutes overhead time at the end of each of the next
orbits, we will integrate in the G130H grating for the next
three orbits, 41 minutes net integration time per orbit, and
so obtain a SNR of ~ 10 per
resolution element for the continuum in the 1200--
1600 Angstrom range. This will allow us to
measure the continuum shape and the strong emission and
absorption lines in this range. We will then side-switch
to the FOS red
side, and use the fifth orbit for a 41-minute exposure in
G190H (SNR~19) and the 6th orbit for a 41-minute exposure
in G270H (SNR~30). For NGC 4569 (Dec. +13)
we have 53 minutes visibility per orbit, requiring one orbit
for GS acq (12 min) plus an A+B1 peakup (7+13 min), and a
second orbit for GS reacq. (6 min) and D1 peakup (22 min),
leaving 18 minutes integration time in G130H in the second
orbit. The third orbit will be used for another 40 minutes
net integration time through G130H, giving a total SNR~22.
We will then side-switch
to the FOS red
side, and use the fourth orbit for a 22-minute exposure in
G190H (SNR~50) and an 11-minute exposure
in G270H (SNR~50). This will allow us to
and also search for weaker features in NGC 4569.
The typical SNRs per resolution element we are
presently aiming for (~ 10-20 in continuum, >10-20 in lines)
will provide the best measurement to date of the UV spectrum
of LINERs. We will consider requesting higher SNR data in
future Cycles, pending the results of these observations.
Real_Time_Justification:
Calibration_Justification:
Additional_Comments:
Fixed_Targets
Target_Number: 1
Target_Name: NGC4569
Alternate_Names: UGC7786
Description: GALAXY,SPIRAL,LINER
Position: RA=12H 36M 49.81S +/- 0.01S,
DEC=+13D 09' 45.8" +/- 0.1",
PLATE-ID=00IY
Equinox: 2000
RV_or_Z: V=-261
Flux: SURF(V)=14.0 +/- 1.0,
F-CONT(2270)=1+/-0.2 E-14
Comments: Nuclear UV sources observed in the FOC
Target_Number: 2
Target_Name: NGC5055
Alternate_Names: UGC8334
Description: GALAXY,SPIRAL,LINER
Position: RA=13H 15M 49.27S +/- 0.01S,
DEC=+42D 01' 46.3" +/- 0.1",
PLATE-ID=01PY
Equinox: 2000
RV_or_Z: V=+503
Flux: SURF(V)=14.0 +/- 1.0,
F-CONT(2270)=1+/-0.2 E-15
Comments: Nuclear UV sources observed in the FOC
Visits
Visit_Number: 1
Visit_Requirements:
On_Hold_Comments:
Visit_Comments:
Exposure_Number: 1
Target_Name: NGC4569
Config: FOS/BL
Opmode: ACQ/PEAK
Aperture: 4.3
Sp_Element: MIRROR
Wavelength:
Optional_Parameters: SCAN-STEP-Y=1.2
SEARCH-SIZE-X=1
SEARCH-SIZE-Y=3
Number_of_Iterations: 1
Time_Per_Exposure: 3s
Special_Requirements: ONBOARD ACQ FOR 2
Exposure_Number: 2
Target_Name: NGC4569
Config: FOS/BL
Opmode: ACQ/PEAK
Aperture: 1.0
Sp_Element: MIRROR
Wavelength:
Optional_Parameters: SCAN-STEP-X=0.61
SCAN-STEP-Y=0.61
SEARCH-SIZE-X=6
SEARCH-SIZE-Y=2
Number_of_Iterations: 1
Time_Per_Exposure: 5s
Special_Requirements: ONBOARD ACQ FOR 3
Exposure_Number: 3
Target_Name: NGC4569
Config: FOS/BL
Opmode: ACQ/PEAK
Aperture: 0.3
Sp_Element: MIRROR
Wavelength:
Optional_Parameters: SCAN-STEP-X=0.17
SCAN-STEP-Y=0.17
SEARCH-SIZE-X=5
SEARCH-SIZE-Y=5
Number_of_Iterations: 1
Time_Per_Exposure: 8s
Special_Requirements: ONBOARD ACQ FOR 4-6
Exposure_Number: 4
Target_Name: NGC4569
Config: FOS/BL
Opmode: ACCUM
Aperture: 1.0
Sp_Element: G130H
Optional_Parameters:
Number_of_Iterations: 1
Time_Per_Exposure: 50M
Special_Requirements: EXPAND
MAX DUR 300%
Comments:
Exposure_Number: 5
Target_Name: NGC4569
Config: FOS/RD
Opmode: ACCUM
Aperture: 1.0
Sp_Element: G190H
Optional_Parameters:
Number_of_Iterations: 1
Time_Per_Exposure: 22M
Special_Requirements: EXPAND
MAX DUR 300%
Comments:
Exposure_Number: 6
Target_Name: NGC4569
Config: FOS/RD
Opmode: ACCUM
Aperture: 1.0
Sp_Element: G270H
Optional_Parameters:
Number_of_Iterations: 1
Time_Per_Exposure: 11M
Special_Requirements: EXPAND
MAX DUR 300%
Comments:
Visits
Visit_Number: 2
Visit_Requirements:
On_Hold_Comments:
Visit_Comments:
Exposure_Number: 1
Target_Name: NGC5055
Config: FOS/BL
Opmode: ACQ/PEAK
Aperture: 4.3
Sp_Element: MIRROR
Wavelength:
Optional_Parameters: SCAN-STEP-Y=1.2
SEARCH-SIZE-X=1
SEARCH-SIZE-Y=3
Number_of_Iterations: 1
Time_Per_Exposure: 10s
Special_Requirements: ONBOARD ACQ FOR 2
Exposure_Number: 2
Target_Name: NGC5055
Config: FOS/BL
Opmode: ACQ/PEAK
Aperture: 1.0
Sp_Element: MIRROR
Wavelength:
Optional_Parameters: SCAN-STEP-X=0.61
SCAN-STEP-Y=0.61
SEARCH-SIZE-X=6
SEARCH-SIZE-Y=2
Number_of_Iterations: 1
Time_Per_Exposure: 10s
Special_Requirements: ONBOARD ACQ FOR 3
Exposure_Number: 3
Target_Name: NGC5055
Config: FOS/BL
Opmode: ACQ/PEAK
Aperture: 0.3
Sp_Element: MIRROR
Wavelength:
Optional_Parameters: SCAN-STEP-X=0.17
SCAN-STEP-Y=0.17
SEARCH-SIZE-X=5
SEARCH-SIZE-Y=5
Number_of_Iterations: 1
Time_Per_Exposure: 10s
Special_Requirements: ONBOARD ACQ FOR 4-6
Exposure_Number: 4
Target_Name: NGC5055
Config: FOS/BL
Opmode: ACCUM
Aperture: 1.0
Sp_Element: G130H
Optional_Parameters:
Number_of_Iterations: 1
Time_Per_Exposure: 123M
Special_Requirements: END ORBIT
Comments:
Exposure_Number: 5
Target_Name: NGC5055
Config: FOS/RD
Opmode: ACCUM
Aperture: 1.0
Sp_Element: G270H
Optional_Parameters:
Number_of_Iterations: 1
Time_Per_Exposure: 35M
Special_Requirements: END ORBIT
Comments:
Exposure_Number: 6
Target_Name: NGC5055
Config: FOS/RD
Opmode: ACCUM
Aperture: 1.0
Sp_Element: G190H
Optional_Parameters:
Number_of_Iterations: 1
Time_Per_Exposure: 41M
Special_Requirements: END ORBIT
Comments:
Data_Distribution ! Defaults indicated; change if desired
Medium: 8MM ! 8MM or 6250BPI or 1600BPI
Blocking_Factor: 10 ! 10 or 1
Ship_To: PI_address
Ship_Via: UPS ! UPS (2-day) or OVERNIGHT
! Overnight shipping done at PI expense
Recipient_Email: ! Needed if Ship_To: is not PI_Address
! <free-text>
__Diagnostic-Sum-Section__
Software-Version (Controller= 2.1)
Preprocessor (Errors= 0 Fatal-Errors= 0 )
Validation (Errors= 0 Fatal-Errors= 0 )
Transformation (Errors= 2 Fatal-Errors= 0 )
CASM (Errors= 0 Fatal-Errors= 0 )
__User-Comments__
Hi!
I am submitting this proposal as I am a co Investigator.
The PI is Dan Maoz.
Anuradha