The disintegrating old open cluster Czernik 3
  We have performed a detailed analysis of the Czernik 3 (Cz3) open cluster by
using deep near-infrared photometry taken with TIRCAM2 on 3.6m Devasthal
optical telescope along with the recently available high quality proper motion
data from the {\it Gaia} DR2 and deep photometric data from Pan-STARRS1. The
cluster has a highly elongated morphology with fractal distribution of stars.
The core and cluster radii of the cluster are estimated as 0.5 pc and 1.2 pc,
respectively. We have identified 45 stars as cluster members using the {\it
Gaia} proper motion data. The distance and age of the cluster are found to be
$3.5\pm0.9$ kpc and $0.9^{+0.3}_{-0.1}$ Gyr, respectively. The slope of the
mass function $`\Gamma'$ in the cluster region, in the mass range
$\sim$0.95$<$M/M$_\odot$$<$2.2, is found to be $-1.01\pm0.43$. The cluster
shows the signatures of mass-segregation and is dynamically relaxed (dynamical
age=10 Myr). This along with its small size, big tidal radius, low
density/large separation of stars, and elongated and distorted morphology,
indicate that the Cz3 is a loosely bound disintegrating cluster under the
influence of external tidal interactions.
