211 citations · 427 across the 6 of their papers we have counts for
8 papers · 1 filter
Detecting Low-Mass Supermassive Black Holes
Himel Ghosh, Smita Mathur, Fabrizio Fiore +1
We demonstrate the feasibility of uncovering supermassive black holes in late-type, quiescent spiral galaxies by detecting signs of very low-level nuclear activity. We use a combin…
Finding Local Low-mass Supermassive Black Holes
Smita Mathur, Himel Ghosh, Laura Ferrarese +1
The low-mass end of the supermassive black hole mass function is unknown and difficult to determine. Here we discuss our successful program to find active nuclei of late type "norm…
Low-Level Nuclear Activity in Nearby Spiral Galaxies
Himel Ghosh, Smita Mathur, Fabrizio Fiore +1
We are conducting a search for supermassive black holes (SMBHs) with masses below 10^7 M_sun by looking for signs of extremely low-level nuclear activity in nearby galaxies that ar…
The Mass of the Black Hole in the Seyfert 1 Galaxy NGC 4593 from Reverberation Mapping
Kelly D. Denney, Misty C. Bentz, Bradley M. Peterson +15
We present new observations leading to an improved black hole mass estimate for the Seyfert 1 galaxy NGC 4593 as part of a reverberation-mapping campaign conducted at the MDM Obser…
A Reverberation-Based Mass for the Central Black Hole in NGC 4151
Misty C. Bentz, Kelly D. Denney, Edward M. Cackett +15
We have undertaken a new ground-based monitoring campaign to improve the estimates of the mass of the central black hole in NGC 4151. We measure the lag time of the broad H beta li…
Chandra Observations of Candidate "True" Seyfert 2 Nuclei
Himel Ghosh, Richard W. Pogge, Smita Mathur +2
The Unification Model for active galactic nuclei posits that Seyfert 2s are intrinsically like Seyfert 1s, but that their broad-line regions (BLRs) are hidden from our view. A Seyf…