lundi 22 juin 2015, par Priyanka Chaturvedi, chercheuse du Physical Research Laboratory d’Ahmedabad (Inde)
Mercredi 1er juillet 2015 à 14h00 , Lieu : Salle de conférence du bâtiment 17
Single lined eclipsing binary systems via radial velocity technique give us a unique opportunity to study the sub stellar candidates and low mass end of the main sequence as companions to brighter primaries. Despite a large number of low mass stars present in our galaxy, masses and radii for these stars are still not determined at higher accuracies, primarily due to their fainter magnitudes in visible band. Radii for stars less massive than Sun are known to be 10% smaller theoretically than observed and temperatures are 5% higher. A high-resolution echelle spectrograph, Physical Research Laboratory Advanced Radial-velocity Abu-sky Search (PARAS) working at a resolution (R) of 67000, coupled with the Physical Research Laboratory Mt. Abu, India 1.2m telescope is used for making observations of primary stars of F, G and K spectral type. I will be presenting the intriguing method used to nail down the orbital parameters of such fascinating eclipsing binary systems followed by highlighting few results discovered by PARAS.