The broad-line region and dust torus size of the Seyfert 1 galaxy
  PGC50427
  We present the results of a three years monitoring campaigns of the $z =
0.024$ type-1 active galactic nucleus (AGN) PGC50427. Through the use of
Photometric Reverberation Mapping with broad and narrow band filters, we
determine the size of the broad-line emitting region by measuring the time
delay between the variability of the continuum and the H$\alpha$ emission line.
The H$\alpha$ emission line responds to blue continuum variations with an
average rest frame lag of $19.0 \pm 1.23$ days. Using single epoch spectroscopy
we determined a broad-line H$\alpha$ velocity width of 1020 km s$^{-1}$ and in
combination with the rest frame lag and adoption a geometric scaling factor $f
= 5.5$, we calculate a black hole mass of $M_{BH} \sim 17 \times 10^{6}
M_{\odot}$. Using the flux variation gradient method, we separate the host
galaxy contribution from that of the AGN to calculate the rest frame 5100\AA~
luminosity at the time of our monitoring campaign. The rest frame lag and the
host-subtracted luminosity permit us to derive the position of PGC50427 in the
BLR size -- AGN luminosity diagram, which is remarkably close to the
theoretically expected relation of $R \propto L^{0.5}$. The simultaneous
optical and NIR ($J$ and $K_{s}$) observations allow us to determine the size
of the dust torus through the use of dust reverberation mapping method. We find
that the hot dust emission ($\sim 1800K$) lags the optical variations with an
average rest frame lag of $46.2 \pm 2.60$ days. The dust reverberation radius
and the nuclear NIR luminosity permit us to derive the position of PGC50427 on
the known $\tau - M{V}$ diagram. The simultaneus observations for the
broad-line region and dust thermal emission demonstrate that the innermost dust
torus is located outside the BLR in PGC50427, supporting the unified scheme for
AGNs. (Abstract shortened, see the manuscript.)
