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We present the results of a recent reverberation mapping campaign for UGC 06728, a nearby low-luminosity Seyfert 1 in a late-type galaxy. Nightly monitoring in the spring of 2015 allowed us to determine an H$beta$ time delay of $tau = 1.4 pm 0.8$ days. Combined with the width of the variable H$beta$ line profile, we determine a black hole mass of $M_{rm BH} = (7.1 pm 4.0) times 10^5$ M$_{odot}$. We also constrain the bulge stellar velocity dispersion from higher-resolution long slit spectroscopy along the galaxy minor axis and find $sigma_{star} = 51.6 pm 4.9$ km s$^{-1}$. The measurements presented here are in good agreement with both the $R_{rm BLR} - L$ relationship and the $M_{rm BH}-sigma_{star}$ relationship for AGNs. Combined with a previously published spin measurement, our mass determination for UGC 06728 makes it the lowest-mass black hole that has been fully characterized, and thus an important object to help anchor the low-mass end of black hole evolutionary models.
Intermediate mass black holes (IMBHs) have masses between the $10^2!-!10^6$ M$_odot$ and are key to our understanding of the formation of massive black holes. The known population of IMBH remains small, with a few hundred candidates and only a handfu
We present 0farcs{14}-resolution Atacama Large Millimeter/submillimeter Array (ALMA) CO(2$-$1) observations of the circumnuclear gas disk in UGC 2698, a local compact galaxy. The disk exhibits regular rotation with projected velocities rising to 450
The existence of binary supermassive black holes (SBHs) is predicted by models of hierarchical galaxy formation. To date, only a single binary SBH has been imaged, at a projected separation of 7.3 parsecs. Here we report the detection of a candidate
We present a multi-wavelength study of the active galactic nucleus in the nearby ($D=14.1$ Mpc) low mass galaxy IC 750, which has circumnuclear 22 GHz water maser emission. The masers trace a nearly edge-on, warped disk $sim$0.2 pc in diameter, coinc
We report results of the first reverberation mapping campaign of I Zwicky 1 during $2014$-$2016$, which showed unambiguous reverberations of the broad H$beta$ line emission to the varying optical continuum. From analysis using several methods, we obt