In this paper we study the evolution of core and corona of nine open clusters using the projected radial density profiles derived from homogeneous CCD photometric data obtained through the 105-cm Kiso Schmidt telescope .
The age and galactocentric distance of the target clusters varies from 16 Myr to 2000 Myr and 9 kpc to 10.8 kpc respectively .
Barring Be 62 , which is young open cluster , other clusters show a uniform reddening across the cluster region .
The reddening in Be 62 varies from E ( B - V ) _ { min } = 0.70 mag to E ( B - V ) _ { max } = 1.00 mag .
The corona of six of the clusters in the present sample is found to be elongated , however on the basis of the present sample it is not possible to establish any correlation between the age and shape of the core .
The elongated core in the case of young cluster Be 62 may reflect the initial conditions in the parental molecular cloud .
The other results of the present study are ( i ) Core radius ‘ r _ { c } ’ and corona size `r _ { cn } ’ /cluster radius `r _ { cl } ’ are linearly correlated .
( ii ) The r _ { c } / r _ { cn } / r _ { cl } are linearly correlated with the number of stars in that region .
( iii ) In the age range 10-1000 Myr , the core and corona shrink with age .
( iv ) We find that in the galactocentric distance range 9 - 10 kpc , the core and corona/cluster extent of the clusters increase with the galactocentric distance .