Determinations of its Absolute Dimensions and Distance by the Analyses of Light and Radial-Velocity Curves

• Main Authors: Jae Woo Lee, Chung-Uk Lee, Chun-Hwey Kim, Young Beom Kang, Jae-Rim Koo
• Format: Article
• Language: English
• Published: Korean Space Science Society (KSSS) 2004-12-01
• Series: Journal of Astronomy and Space Sciences
• Subjects: contact binary; CK Boo; absolute dimension; distance
• Online Access: http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2004/v21n4/OJOOBS_2004_v21n4_275.pdf

We completed the light curves of the contact binary CK Boo for 13 nights from June to July in 2004 using the 1-m reflector and BVR filters at Mt. Lemmon Optical Astronomy Observatory, and determined four new times of minimum light (three timings for primary eclipse, one for secondary). With contact mode of the 1998-version Wilson-Devinney binary model, we analyzed our BVR light curves and Rucinski & Lu (1999)'s radial-velocity ones. As a result, we found CK boo to be A-type overcontact binary (f=84%) with the low mass ratio (q=0.11) and orbital inclination (i=65°). Absolute dimensions of the system are determined from our new solution; M1=1.42M⊙, M2=0.15M⊙, R1=1.47R⊙, R2=0.59M⊙, and the distance to it is derived as about 129pc. Our distance is well consistent with that (157±33pc) from the Hipparcos trigonometric parallax within the limit of the error yielded by the latter.