On the Anomaly of Balmer Line Profiles of A-Type Stars. Fundamental binary systems

In previous work, Gardiner et al. (1999) found evidence for a discrepancy between the T e f f obtained from Balmer lines with that from photometry and fundamental values for A-type stars. An investigation into this anomaly is presented using Balmer line profiles of stars in binary system with fundamental values of both T e f f and log g. A revision of the fundamental parameters for binary systems given by Smalley & Dworetsky (1995) is also presented. The T e f f obtained by fitting Hα and Hβ line profiles is compared to the fundamental values and those obtained from uvby photometry. We find that the discrepancy found by Gardiner et al. (1999) for stars in the range 7000 K ≤ T e f f ≤ 9000 K is no longer evident.