CAOSP abstracts, Volume: 55, No.: 1, year: 2025

Author(s): Elsanhoury, W.H.
Journal: Contributions of the Astronomical Observatory Skalnaté Pleso, vol. 55, no. 1, p. 38-59.
Date: 02/2025
Title: Kinematics of high-velocity stars utilizing LAMOST and Gaia DR3 archives within 100 kpc
Keyword(s): High-velocity stars, Gaia DR3, Kinematics, Oort constants.
Pages: 38 -- 59
DOI: https://doi.org/10.31577/caosp.2025.55.1.38
NASA ADS Abstract Service: 2025CoSka..55a..38E
Citation:
License: This work is licensed under a Creative Commons Attribution 4.0 International License

Abstract: The kinematic parameters identified from high-velocity stars situated within ∼ 100 kpc are examined and analyzed. We included three high-velocity programs comprising 591, 87, and 519 stars as a function of distances ranging from 0.10 kpc to nearly 109 kpc. In this analysis, we will determine the spatial velocities (U, V, W) in galactic coordinates along with their velocity dispersion (σ₁, σ₂, σ₃), the convergent point (A_o, D_o) and, therefore, the solar motion (S_☉). In conclusion, we are calculating the first Oort constant (A=11.94 ± 0.29 km s^-1 kpc^-1) and the second one (i.e., B=-17.78 ± 0.24 km s^-1 kpc^-1), the angular rotation rate |A - B| = 25.07 ± 5.01 km s^-1 kpc^-1, and the average rotational velocity V_o = 243.72 ± 15.61 km s^-1.