Broad Band Photometric Reverberation Mapping of NGC 4395
  We present results of broad band photometric reverberation mapping (RM) to
measure the radius of the broad line region, and subsequently the black hole
mass (M$_{\rm BH}$), in the nearby, low luminosity active galactic nuclei (AGN)
NGC 4395. Using the Wise Observatory's 1m telescope equipped with the SDSS
g$'$, r$'$ and i$'$ broad band filters, we monitored NGC 4395 for 9 consecutive
nights and obtained 3 light curves each with over 250 data points. The g$'$ and
r$'$ bands include time variable contributions from H$\beta$ and H$\alpha$
(respectively) plus continuum. The i$'$ band is free of broad lines and covers
exclusively continuum. We show that by looking for a peak in the difference
between the cross-correlation and the auto-correlation functions for all
combinations of filters, we can get a reliable estimate of the time lag
necessary to compute M$_{\rm BH}$. We measure the time lag for H$\alpha$ to be
$3.6 \pm 0.8 $ hours, comparable to previous studies using the line resolved
spectroscopic RM method. We argue that this lag implies a black hole mass of
M$_{\rm BH} = (4.9 \pm 2.6) \times 10^{4}$ \Msun .
