Kinematics And Ellipsoidal Motion Of The Mid To Late M-Type Stars

Abstract

Truly, kinematics in the Solar neighborhood has provided important information both for the structure and for the evolution of the Galaxy since the early 20th century. The relationship between Oort constants and the ratio of the velocity dispersion are important quantities in stellar kinematics. In the present paper, we calculated the kinematical parameters and the Oort constants of various samples of late to intermediate M-type stars. We calculated the velocity dispersion (σ_1,σ_2,σ_3 ) in units of km s-1 for the samples under study. The longitude of the vertex (l_2 ) having negative values with our analysis; i.e., the program I (538 stars), l_2 =-0_.^o 5410, program II (100 stars), l_2=-0_.^o 4937 and program III (60 stars), l_2=-0_.^o 9495. We calculate the Oort constants as A=14.69+-0.61 km s-1 kpc-1 and B=-16.70+-0.67 km s-1 kpc-1, and the rotational velocity V_o=257.38+-9.40 km s^(-1). A possible explanation for the overestimated values of the second Oort constants has been presented.

17 pages, 1 figure, 4 tables

References in corpus (8)

• Gaia Early Data Release 3: The astrometric solution
• Constraining the Age-Activity Relation for Cool Stars: The SDSS DR5 Low-Mass Star Spectroscopic Sample
• The First Direct Measurements of Magnetic Fields on Very Low-Mass Stars
• New Worlds on the Horizon: Earth-Sized Planets Close to Other Stars
• Local Stellar Kinematics and Oort Constants from the LAMOST A-type Stars
• An investigation of poorly studied open cluster NGC 4337 using multi-color photometric and Gaia DR2 astrometric data
• Analysis of galaxy kinematics based on Cepheids from the Gaia DR2 Catalogue
• Galactic Rotation Parameters Based on Stars from Activ Star-Forming Regions with Data from the Gaia DR2 Catalogue