Near-infrared study of open clusters Teutsch 10 and Teutsch 25

Abstract

The astrophysical parameters have been estimated for two unstudied open star clusters Teutsch 10 and Teutsch 25 using the Two Micron All Sky Survey (2MASS) database. Radius is estimated as 4.5 arcmin for both clusters using radial density profiles. We have estimated proper motion values in both RA and DEC directions as 2.28±0.3 and -0.38±0.11 mas yr−1 for Teutsch 10 and 0.48±0.3 and 3.35±0.16 mas yr−1 for Teutsch 25 using PPMXL1http://vizer.cfa.harvard.edu/vizbin/VizieR?-source=I/317.1 catalog. By estimating the stellar membership probabilities, we have identified 30 and 28 most likely members for Teutsch 10 and Teutsch 25 respectively. We have estimated the reddening as E(B-V)=0.96±0.3 mag for Teutsch 10 and 0.58±0.2 mag for Teutsch 25, while the corresponding distances are 2.4±0.2 and 1.9±0.1 kpc. Ages of 70±10 Myr for Teutsch 10 and 900±100 Myr for Teutsch 25 are estimated using the theoretical isochrones of metallicity Z = 0.019. The mass function slopes are derived as 1.23±0.30 and 1.09±0.35 for Teutsch 10 and Teutsch 25 respectively. Estimated mass function slope for both the clusters are close to the Salpeter value (x=1.35) within the errors. Estimated values of dynamical relaxation time are found to be less than cluster’s age for these objects. This concludes that both objects are dynamically relaxed. The possible reason for relaxation may be due to dynamical evolution or imprint of star formation or both.