8610( 4) - 05/01/00 06:10 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8610 Version: 4 Check-in Date: 01-May-2000 06:10:15 1.Proposal Title: A Black Hole Offset from the Host Galaxy Mass Center? ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 9 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Carole Mundell Liverpool John Moores University CoI: Prof. Andrew Wilson University of Maryland N CoI: Neil Nagar University of Maryland N CoI: Dr. Pierre Ferruit Observatoire de Lyon N ------------------------------------------------------------------------------------ 5. Abstract It has been suggested that the central regions of many galaxies are unlikely to be in a static steady state, with instabilities caused by sinking satellites, the influence of a supermassive black hole or residuals of galaxy formation, resulting in the nuclear black hole orbiting the galaxy center. The observational signature of such an orbiting black hole is an offset of the active nucleus (AGN) from the kinematic center defined by the galaxy rotation curve. This orbital motion may provide fuelling of the AGN, as the hole `grazes' on the ISM, and bent radio jets, due to the motion of their source. The early type (E/SO) Seyfert galaxy, NGC2110, with its striking twin, `S'-shaped radio jets, is a unique and valuable test case for the offset-nucleus phenomenon since, despite its remarkably normal rotation curve, its kinematically-measured mass center is displaced both spatially (260 pc) and kinematically (170 km s^-1) from the active nucleus, as seen both in optical and radio studies. However, the central kinematics, where the rotation curve rises most steeply, are inaccessible with ground-based resolutions. The proposed WFPC2 imaging and long-slit STIS spectroscopy of NGC 2110 will enable determination of the structure and kinematics of gas moving in the galactic potential on subarcsecond scales and investigate the origin of the off-set nucleus. ------------------------------------------------------------------------------------ 8610( 4) - 05/01/00 06:10 - [ 2] Observations Description ------------------------ We propose spatially resolved imaging and spectroscopy of the host galaxy of NGC2110. WFPC2 will be used to obtain the first post-COSTAR Ha image and STIS to obtain the first sub-arcsecond observations fo the host galaxy kinematics, also in Ha. The redshift of NGC2110 (V = 2402 km/s) requires the use of an LRF to image Ha, and FR680P15 will place the image on the PC chip. This high resolution PC image will then be used for direct comparison with our long slit spectra to define the precise location of the slit with respect to the spatial structure after the spectroscpic observations have been made. In addition, one continuum exposure with the F791W filter, which is effectively free from line contamination, will be obtained to provide accurate continuum determination and subtraction. The STIS observations will use a 52x0.2 slit, positioned along the galaxy kinematic major axis in PA 161 deg (which will cover both the active nucleus and kinematic (galaxy-mass) center determined from ground-based studies) with t he G750M grating (centered at 6581A to include the redshifted Ha line at 6615 A). The observations are separated into two visits, with one visit for a single imaging orbit and the other visit for two spectroscopy orbits. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8610( 4) - 05/01/00 06:10 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC2110 GALAXY, SEYFERT, EXT- RA=05H 52M 11.3762S +/- 0.015", J2000 V = 2404 SURF-LINE(6563)=9.9e-14 MEDIUM DEC=-07D 27' 22.513" +/- 0.015" SURF-CONT(5461)=1.7e-15 SURF-CONT(7164)=3.3e-15 Coordinate Source: OTHER_SOURCE Comments: Line emission surf-brightness from Mulchaey et al., 1994 (WF/PC deconvolved) - peak flux 1.3e-11 ergs/s/cm2/arcsec2 (filter width 131 A). Also from Mulchaey et al. (1994), red (7164 A) and green (5461 A)continuum peak fluxes of 3.3e-15 and 1.7e-15 ergs/s/cm2/A/arcsec resp. 8610( 4) - 05/01/00 06:10 - [ 4] Visit: 01 Visit Priority: 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 NGC2110 WFPC2 IMAGE PC1 F791W CR-SPLIT=0.5 1 260 S Comments: Line-free continuum exposure for 2 and 3. ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC2110 WFPC2 IMAGE LRF LRF 6615 CR-SPLIT=0.5 1 600 S Comments: The redshift of NGC2110 (V = 2402 km/s) requires the LRF to image Ha (FR680P15 will place the image on the PC chip). ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC2110 WFPC2 IMAGE LRF LRF 6615 CR-SPLIT=0.5 1 600 S ------------------------------------------------------------------------------------------------------------------------------------ 8610( 4) - 05/01/00 06:10 - [ 5] Visit: 02 Visit Priority: Visit Requirements: ORIENT 21D TO 31D ORIENT 201D TO 211D On Hold Comments: Additional Comments: Slit PA required to be 161 +- 5 deg, so ORIENT 21-31D or 201-211D are acceptable Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC2110 STIS/C ACQ F28X50L MIRROR ACQTYPE=DIFFUSE, 1 20 S CD P DIFFUSE-CENTER=FLUX-CENTROID, CHECKBOX=3 Comments: ONBOARD ACQ for 2 ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC2110 STIS/C ACCUM 52X0.2 G750M 6581 CR-SPLIT=6,BINAXIS1=2 1 1350 S POS TARG 0,-0.1521 CD ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC2110 STIS/C ACCUM 52X0.2 G750M 6581 CR-SPLIT=6,BINAXIS1=2 1 1350 S CD ------------------------------------------------------------------------------------------------------------------------------------ 5 NGC2110 STIS/C ACCUM 52X0.2 G750M 6581 CR-SPLIT=6,BINAXIS1=2 1 1350 S POS TARG 0, 0.1521 CD ------------------------------------------------------------------------------------------------------------------------------------ 8610( 4) - 05/01/00 06:10 - [ 6] Summary Form for Proposal 8610 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1 LRF F28X50LP 52X0.2 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 STIS/CCD ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ACQ ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=0.5 CHECKBOX=3 BINAXIS1=2 CR-SPLIT=6 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 21D TO 31D ORIENT 201D TO 211D POS TARG 0,-0.1521 POS TARG 0, 0.1521 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F791W LRF MIRROR G750M ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC2110 ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 6615 6581 ------------------------------------------------------------------------------------------------------------------------------------