15263( 2) - 11-Jul-2017 15:26:42 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15263 Version: 2 Check-in Time: 11-Jul-2017 15:26:42 STScI Edit Number: 0 Title The Host Galaxy of the Low Mass Black Hole in UGC 06728 ------------------------------------------------------------------------------------ Type Cycle GO 25 ------------------------------------------------------------------------------------ Investigators Contact? PI: Prof. Misty C. Bentz Georgia State University Research Y Foundation CoI: Dr. Merida Batiste Georgia State University Research N Foundation CoI: Dr. Monica Valluri University of Michigan N CoI: Dr. Christopher A. Onken Australian National University N CoI: Ms. Caroline Roberts Georgia State University Research N Foundation ------------------------------------------------------------------------------------ Abstract We propose to obtain high-resolution, multicolor imaging of the host-galaxy of UGC 06728, a nearby (z=0.0065) low-luminosity Seyfert. A recent reverberation-mapping campaign has constrained the black hole mass to 7x10^5 M_sun, but little is currently known about the host galaxy due to the lack of spatial resolution in existing, seeing-limited images. Based on the black hole mass and the bulge stellar velocity dispersion, it is likely that a black hole mass could also be derived from modeling the nuclear stellar dynamics of UGC 06728. The number of galaxies where comparison of stellar dynamics and reverberation mapping is possible is very small (<10) due to their non-overlapping technical requirements, so UGC 06728 is an important target for testing the consistencies of black hole masses from different techniques. The proposed images will allow us to characterize the host-galaxy features and morphology for the first time. They will also allow us to determine the central stellar surface brightness for follow-up AO-assisted near-IR integral field spectroscopy, accurately constrain the stellar mass-to-light ratio of the galaxy, and correct the AGN luminosity for starlight contamination (to include UGC 06728 at the low end of the AGN R-L relationship). We will also investigate the globular cluster population around the galaxy and the potential to determine its distance using the globular cluster luminosity function method. The proposed observations will facilitate the direct comparison of masses from reverberation mapping and stellar dynamics, which is critical to ensure that all black holes, from Local Group galaxies to z~7 quasars, are on the same mass scale. ------------------------------------------------------------------------------------ Observations Description ------------------------ We will obtain multi-color high-resolution imaging of the host galaxy of the nearby reverberation-mapped Seyfert UGC06728. We will use WFC3 in the following configurations: UVIS channel with filters F547M (medium V ) and F814W (I), and IR channel with the F160W (H) filter. The images will allow us to investigate the properties of the host galaxy, such as its basic morphological classification and the presence of bars, rings, 15263( 2) - 11-Jul-2017 15:26:42 - [ 2] nuclear spirals, and dust lanes. We will carry out detailed two-dimensional surface brightness decompositions of the images, allowing us to constrain the background sky contribution and separate the bright unresolved AGN from the faint, resolved host galaxy. The F160W filter will provide high spatial-resolution maps of the central stellar surface brightness that we need to plan our observations for constraining the black hole mass through AO-assisted near-IR integral field spectroscopy of the nuclear stellar dynamics. The F547M and F814W filters together will allow us to determine the stellar mass-to-light ratio through a commonly-used color, V-I (e.g., Bell & de Jong 2001). Furthermore, Into & Portinari (2013) find that the V-I color is least affected by dust extinction internal to a galaxy, which will be important for UGC06728 as it is inclined to our line of sight. The F547M and F160W filters will provide a second, separate probe of the galaxy stellar content that is also commonly used (V-H). Finally, the F547M filter will also ensure that we have an image of the host galaxy in a flat part of the stellar spectrum, consistent with HST images previously obtained for the reverberation sample, and facilitating the correction of the AGN continuum luminosity at rest-frame 5100A for contamination from starlight. This filter will additionally provide information on potential globular clusters in a passband similar to V , where the Milky Way population has been well calibrated. We require 2 orbits to acquire deep observations in all three filters. For optical observations of AGN host galaxies with HST, we have found that a set of short+long exposures provides the required dynamic range to separate the bright, unresolved AGN point source from the faint, extended host galaxy in the final drizzled images. The saturated pixels in the nucleus in the long exposures can be corrected by scaling up the same pixels in the shorter exposures by the appropriate exposure time ratio before drizzling the sets together. For the F547M and F814W images, we will take two sets of short+long exposures separated by a standard 2-point dithering pattern to facilitate the rejection of cosmic rays and detector artifacts (e.g., transient warm pixels). For the F160W observations, we will use the standard STEP50 sequence in MULTIACCUM mode, allowing for multiple samplings of the AGN PSF before it saturates and deep exposures for the fainter host galaxy. We will utilize a 4-point dithering strategy for the F160W observations. The galaxy is compact and will cleanly fit on one chip of the UVIS detector, but it is also inclined to our line of sight, so we will set some loose ORIENT constraints to ensure that the major axis is oriented more-or-less along the widest part of the chip. Based on our surface brightness decompositions of ground-based images, we estimate the AGN PSF to be g = 16.3mag and r = 16.0mag, although this is likely an overestimate of the brightness given our inability to cleanly separate the AGN from the bulge. But taking these estimates at face value, we estimate a time to saturation in F547M of 156 s and in F814W of 125 s in the central pixels of the AGN PSF. AGNs are highly variable, so we will keep our short exposures significantly shorter than these estimates to ensure that we do not saturate. The high declination of UGC06728 provides a visibility per orbit of approximately 60min. Accounting for the typical overheads of the observatory and instrument, the total estimated exposure times in each filter are 1750s for 15263( 2) - 11-Jul-2017 15:26:42 - [ 3] F547M, 1750s for F814W, and 1700s for F160W. Using the WFC3 exposure time calculator, we estimate that we will reach limiting surface brightnesses in each drizzled image (defined here as S/N~5 per pixel) of mu_V = 21.5mag/arcsec^2, mu_I = 21.0mag/arcsec^2, and mu_H = 22.0mag/arcsec^2. Additionally, we will be able to identify potential globular clusters at S/N~5 (for point sources in a 0.2" circular aperture) down to m_V = 26.25mag. The globular cluster luminosity function method relies on identifying clusters down to 1mag below the luminosity function turn over. These observations would allow us to constrain a turn over at a faint-end limit of m_V = 25.25mag, corresponding to a distance of D=38Mpc (assuming M(V, TO) = -7.68mag for the Milky Way; Rejkuba 2012). This is well beyond the estimated distance of the galaxy based on its observed redshift (z = 0.0065, D=27Mpc) and provides a large buffer for potentially strong peculiar velocities. ------------------------------------------------------------------------------------ 15263( 2) - 11-Jul-2017 15:26:42 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 UGC-6728 GALAXY, SEYFERT RA=11H45M16.0070S, J2000 V = 15.2 DEC=+79D40'53.41" Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 15263( 2) - 11-Jul-2017 15:26:42 - [ 5] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.145 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 46.84 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-BOX-MIN Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.572 Line_Spacing 0.365 Coordinate_Frame POS-TARG Pattern_Orient 18.528 Angle_Between_Sides 74.653 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 15263( 2) - 11-Jul-2017 15:26:42 - [ 6] Visit: 01 Visit Requirements: ORIENT 300D TO 10 D; ORIENT 120D TO 190 D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 UGC-6728 WFC3/UVI ACCUM UVIS1 F547M FLASH=11.0 1 75 S (150 PATTERN 1 1-2 S S) ------------------------------------------------------------------------------------------------------------------------------------ 2 UGC-6728 WFC3/UVI ACCUM UVIS1 F547M FLASH=3.0 1 810 S S (1620 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 UGC-6728 WFC3/IR MULTIAC IR F160W SAMP-SEQ=STEP50, NSAMP=13 1 DEF PATTERN 2 3 CUM (1596.934 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 UGC-6728 WFC3/UVI ACCUM UVIS1 F814W 1 900 S PATTERN 1 4-5 S (1800 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 UGC-6728 WFC3/UVI ACCUM UVIS1 F814W FLASH=10.0 1 75 S (150 S S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ UGC-6728 1 WFC3/UVI ACCUM UVIS1 F547M 1 none none none 1 N/A S UGC-6728 1 WFC3/UVI ACCUM UVIS1 F547M 2 none none none 1 N/A S UGC-6728 2 WFC3/UVI ACCUM UVIS1 F547M 1 none none none 1 N/A S UGC-6728 2 WFC3/UVI ACCUM UVIS1 F547M 2 none none none 1 N/A S UGC-6728 3 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM UGC-6728 3 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM UGC-6728 3 WFC3/IR MULTIAC IR F160W 3 none none none 2 N/A CUM UGC-6728 3 WFC3/IR MULTIAC IR F160W 4 none none none 2 N/A CUM UGC-6728 4 WFC3/UVI ACCUM UVIS1 F814W 1 none none none 2 N/A S UGC-6728 4 WFC3/UVI ACCUM UVIS1 F814W 2 none none none 2 N/A S 15263( 2) - 11-Jul-2017 15:26:42 - [ 7] Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ UGC-6728 5 WFC3/UVI ACCUM UVIS1 F814W 1 none none none 2 N/A S UGC-6728 5 WFC3/UVI ACCUM UVIS1 F814W 2 none none none 2 N/A S 15263( 2) - 11-Jul-2017 15:26:42 - [ 8] Summary Form for Proposal 15263 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR, UVIS1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR, WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters FLASH=10.0, FLASH=11.0, FLASH=3.0, NSAMP=13, SAMP-SEQ=STEP50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 120D TO 190 D, ORIENT 300D TO 10 D, PATTERN 1 1-2, PATTERN 1 4-5, PATTERN 2 3 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F160W, F547M, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names UGC-6728 ------------------------------------------------------------------------------------------------------------------------------------