Kalaya is the daughter-in-law of Chin Sophonpanich and the wife of Chote Sophonpanich. She graduated with a Bachelor of Science (Honors) from the Faculty of Science at Chulalongkorn University in 1961, and received a Colombo scholarship to study for a master's degree, also receiving scholarships at doctoral level to read nuclear physics at Imperial College London where she earned a Ph.D. in high-energy nuclear physics in 1970.