Analysis of the young open cluster Trumpler 2 using Gaia DR3 data

Abstract

We present an investigation of the open cluster Trumpler 2 using Gaia DR3 photometric, astrometric and spectroscopic data. 92 stars were identified as likely members of the cluster, with membership probabilities greater than 0.5. The mean proper-motion components of the cluster are derived as ($\mu_{\alpha}\cos \delta$, $\mu_{\delta}$)=($1.494 \pm 0.004$, $-5.386 \pm 0.005$) mas yr$^{-1}$. By comparing the Gaia based colour-magnitude diagram with the PARSEC isochrones scaled to $z=0.0088$, age, distance modulus and reddening are simultaneously estimated as $t=110 \pm 10$ Myr, $\mu=10.027 \pm0.149$ mag and $E(G_{\rm BP}-G_{\rm RP})=0.452\pm 0.019$ mag, respectively. The total mass of the cluster is estimated as 162 $M/M_{\odot}$ based on the stars with membership probabilities $P > 0$. The Mass function slope is derived to be $\Gamma = 1.33 \pm 0.13$ for Trumpler 2. This value is in a good agreement with that of of Salpeter. Galactic orbit analyses show that the Trumpler 2 orbits in a boxy pattern outside the solar circle and belongs to the young thin-disc component of the Galaxy.