Optical Observations of star clusters NGC 1513 and NGC 4147; white dwarf
  WD1145+017 and $K$ band imaging of star forming region Sh2-61 with the 3.6
  meter Devasthal Optical Telescope
  The $UBVRI$ CCD photometric data of open star cluster NGC 1513 are obtained
with the 3.6-m Indo-Belgian Devasthal optical telescope (DOT). Analyses of the
GAIA EDR3 astrometric data have identified 106 possible cluster members. The
mean proper motion of the cluster is estimated as
$\mu_{\alpha}Cos{\delta}=1.29\pm0.02$ and $\mu_{\delta}=-3.74\pm0.02$ mas
yr$^{-1}$. Estimated values of reddening $E(B-V)$ and distance to the NGC 1513
are 0.65$\pm$0.03 mag and 1.33$\pm$0.1 kpc respectively. An age of $225\pm25$
Myr is assigned to the cluster by comparing theoretical isochrones with deep
observed cluster sequence. Using observations taken with the 3.6-m DOT, values
of distance and age of the galactic globular cluster NGC 4147 are estimated as
$18.2\pm0.2$ Kpc and $14\pm2$ Gyr respectively. The optical observations of
planetary transit around white dwarf WD1145+017 and $K$-band imaging of
star-forming region Sharpless Sh 2-61 demonstrate observing capability of 3.6-m
DOT. Optical and near-infrared observations of celestial objects and events are
being carried out routinely with the 3.6-m DOT. They indicate that the
performance of the telescope is at par with those of other similar telescopes
located elsewhere in the world. We therefore state that this observing facility
augurs well for multi-wavelength astronomy including study of astrophysical
jets.
