Quasars physical properties study based on the medium-band photometric
  survey
  The study is about the quasars cosmological evolution. We used the
medium-band photometric survey at the 1-m Schmidt telescope of the Byurakan
Astrophysical Observatory. The HS47-22 field with an area of 2.38 square
degrees has been selected. We have classified objects and composed a sample of
quasars using broadband photometric data and morphological classification from
the DECaLS survey, infrared photometry from the WISE survey, spectroscopy from
the SDSS survey, ROSAT X-ray data, FIRST radio data and stellar parallax data
from the GAIA survey. We have compiled a sample of 682 quasars, determined
their photometric redshifts from the medium-band photometric data, and
calculated the absolute stellar magnitudes. The space density of quasars was
calculated for different luminosity ranges at different redshifts using the
$\lambda$-CDM model with $\Omega_m = 0.3$ and $\Omega_\lambda = 0.7$. In this
paper, we present the comparison of our results with other works.
