The Future of Direct Supermassive Black Hole Mass Estimates

(Abridged) The repeated discovery of supermassive black holes (SMBHs) at the centers of galactic bulges, and the discovery of relations between the SMBH mass (M) and the properties of these bulges, has been fundamental in directing our understanding of both galaxy and SMBH formation and evolution. However, there are still many questions surrounding the SMBH - galaxy relations. For example, are the scaling relations linear and constant throughout cosmic history, and do all SMBHs lie on the scaling relations? These questions can only be answered by further high quality direct M estimates from a wide range in redshift. In this paper we determine the observational requirements necessary to directly determine SMBH masses, across cosmological distances, using current M modeling techniques. We also discuss the SMBH detection abilities of future facilities. We find that if different M modeling techniques, using different spectral features, can be shown to be consistent, then both 30 m ground- and 16 m space-based telescopes will be able to sample M 1e9Msol across ~95% of cosmic history. However, we find that the abilities of ground-based telescopes critically depend on future advancements in adaptive optics systems; more limited AO systems will result in limited effective spatial resolutions, and forces observations towards the near-infrared where spectral features are weaker and more susceptible to sky features. Ground-based AO systems will always be constrained by relatively bright sky backgrounds and atmospheric transmission. The latter forces the use of multiple spectral features and dramatically impacts the SMBH detection efficiency. The most efficient way to advance our database of direct SMBH masses is therefore through the use of a large (16 m) space-based UVOIR telescope.Comment: PASP Accepte

How Special Are Brightest Cluster Galaxies? The Impact of Near-Infrared Luminosities on Scaling Relations for BCGs

Using the extended J, H and K magnitudes provided by the 2MASS data archive, we consider the position of brightest cluster galaxies (BCGs) in the observed relations between inferred supermassive black hole (SMBH) mass and the host galaxy properties, as well as their position in the stellar velocity dispersion and luminosity ( ∗ − L) relation, compared to E and S0 galaxies. We find that SMBH masses (M•) derived from near-infrared (NIR) magnitudes do not exceed 3×109M⊙ and that these masses agree well with the predictions made from ∗. In the NIR, there is no evidence that BCGs leave the ∗ − L relation defined by less luminous galaxies. The higher SMBH masses predicted from V-band luminosities (M• . 1010.5M⊙) are attributed to the presence of extended envelopes around the BCGs, however, this will need to be confirmed using deeper multiwavelength imaging

High Accuracy Near-infrared Imaging Polarimetry with NICMOS

The findings of a nine orbit calibration plan carried out during HST Cycle 15, to fully determine the NICMOS camera 2 (2.0 micron) polarization calibration to high accuracy, are reported. Recently Ueta et al. and Batcheldor et al. have suggested that NICMOS possesses a residual instrumental polarization at a level of 1.2-1.5%. This would completely inhibit the data reduction in a number of GO programs, and hamper the ability of the instrument to perform high accuracy polarimetry. We obtained polarimetric calibration observations of three polarimetric standards at three spacecraft roll angles separated by ~60deg. Combined with archival data, these observations were used to characterize the residual instrumental polarization in order for NICMOS to reach its full potential of accurate imaging polarimetry at p~1%. Using these data, we place an 0.6% upper limit on the instrumental polarization and calculate values of the parallel transmission coefficients that reproduce the ground-based results for the polarimetric standards. The uncertainties associated with the parallel transmission coefficients, a result of the photometric repeatability of the observations, are seen to dominate the accuracy of p and theta. However, the updated coefficients do allow imaging polarimetry of targets with p~1.0% at an accuracy of +/-0.6% and +/-15deg. This work enables a new caliber of science with HST.Comment: 13 pages, 9 figures, PASP accepte

High Accuracy Imaging Polarimetry with NICMOS

The ability of NICMOS to perform high accuracy polarimetry is currently hampered by an uncalibrated residual instrumental polarization at a level of 1.2-1.5%. To better quantify and characterize this residual we obtained observations of three polarimetric standard stars at three separate space-craft roll angles. Combined with archival data, these observations were used to characterize the residual instrumental polarization to enable NICMOS to reach its full polarimetric potential. Using these data, we calculate values of the parallel transmission coefficients that reproduce the ground-based results for the polarimetric standards. The uncertainties associated with the parallel transmission coefficients, a result of the photometric repeatability of the observations, dominate the accuracy of p and theta. However, the new coefficients now enable imaging polarimetry of targets with p~1.0% at an accuracy of +/-0.6% and +/-15 degrees.Comment: 5 pages, 2 figures. Contributed talk, "Astronomical Polarimetry 2008. Science from Small to Large Telescopes" La Malbaie, Quebec, Canada, 200