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تسجيل مستخدم جديدKinematic Properties of Young Intermediate- and Low-Mass Stars from the Gaia DR2 Catalogue
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We have studied the kinematic properties of young pre-main-sequence stars. We have selected these stars based on data from the Gaia DR2 catalogue by invoking a number of photometric infrared surveys. Using 4564 stars with parallax errors less than 20%, we have found the following parameters of the angular velocity of Galactic rotation: $Omega_0 =28.84pm0.10$ km s$^{-1}$ kpc$^{-1}$, $Omega^{}_0=-4.063pm0.029$ km s$^{-1}$ kpc$^{-2}$ and $Omega^{}_0=0.766pm0.020$ km s$^{-1}$ kpc$^{-3}$, where the Oort constants are $A=16.25pm0.33$ km s$^{-1}$ kpc$^{-1}$ and $B=-12.58pm0.34$ km s$^{-1}$ kpc$^{-1}$. The circular rotation velocity of the solar neighborhood around the Galactic center is $V_0=230.7pm4.4$ km s$^{-1}$ for the adopted Galactocentric distance of the Sun $R_0=8.0pm0.15$ kpc. The residual velocity dispersion for the stars considered is shown to be low, suggesting that they are extremely young. The residual velocity dispersion averaged over three coordinates is $sim$11 km s$^{-1}$ for Herbig Ae/Be stars and $sim$7 km s$^{-1}$ for T Tauri stars.
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