Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2010-07-23
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
19 pages, 6 figures and 6 tables, accepted for publication in Publication of the Astronomical Society of Japan
Scientific paper
New high resolution spectra of the short period (P~1.76 days) young detached binary LT CMa are reported for the first time. By combining the results from the analysis of new radial velocity curves and published light curves, we determine values for the masses, radii and temperatures as follows: M_1= 5.59 (0.20) M_o, R_1=3.56 (0.07) R_o and T_eff1= 17000 (500) K for the primary and M_2=3.36 (0.14) M_o, R_2= 2.04 (0.05) R_o and T_eff2= 13140 (800) K for the secondary. Static absorbtion features apart from those coming from the close binary components are detected in the several spectral regions. If these absorbtion features are from a third star, as the light curve solutions support, its radial velocity is measured to be RV_3=70(8) km s^-1. The orbit of the binary system is proved to be eccentric (e=0.059) and thus the apsidal motion exists. The estimated linear advance in longitude of periastron corresponds to an apsidal motion of U=694+/-5 yr for the system. The average internal structure constant log k_2,obs=-2.53 of LT CMa is found smaller than its theoretical value of log k_2,theo=-2.22 suggesting the stars would have more central concentration in mass. The photometric distance of LT CMa (d=535+/-45 pc) is found to be much smaller than the distance of CMa OB1 association (1150 pc) which rules out membership. A comparison with current stellar evolution models for solar metallicity indicates that LT CMa (35 Myr) is much older than the CMa OB1 association (3 Myr), confirming that LT CMa is not a member of CMa OB1. The kinematical and dynamical analysis indicate LT CMa is orbiting the Galaxy in a circular orbit and belongs to the young thin-disk population.
Bakis Hicran
Bakis Volkan
Bilir Selcuk
Bulut Ibrahim
Demircan Osman
No associations
LandOfFree
Absolute Dimensions and Apsidal Motion of the Young Detached System LT Canis Majoris does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Absolute Dimensions and Apsidal Motion of the Young Detached System LT Canis Majoris, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Absolute Dimensions and Apsidal Motion of the Young Detached System LT Canis Majoris will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-138869