The Seoul National University AGN monitoring project. II. BLR size and
  black hole mass of two AGNs
  Active galactic nuclei (AGNs) show a correlation between the size of the
broad line region (BLR) and the monochromatic continuum luminosity at 5100 \AA,
allowing black hole mass estimation based on single-epoch spectra. However, the
validity of the correlation is yet to be clearly tested for high-luminosity
AGNs. We present the first reverberation-mapping results of the Seoul National
University AGN monitoring program (SAMP), which is designed to focus on
luminous AGNs for probing the high end of the size-luminosity relation. We
report time lag measurements of two AGNs, namely, 2MASS J10261389+5237510 and
SDSS J161911.24+501109.2, using the light curves obtained over a $\sim$1000 day
period with an average cadence of $\sim$10 and $\sim$20 days, respectively for
photometry and spectroscopy monitoring. Based on a cross-correlation analysis
and H$\beta$ line width measurements, we determine the H$\beta$ lag as
$41.8^{+4.9}_{-6.0}$ and $52.6^{+17.6}_{-14.7}$ days in the observed-frame, and
black hole mass as $3.65^{+0.49}_{-0.57} \times 10^7 M_{\odot}$ and
$23.02^{+7.81}_{-6.56} \times 10^7 M_{\odot}$, respectively for 2MASS J1026 and
SDSS J1619.
