Gamma Coronae Borealis (γ CrB) is a star in the constellationCorona Borealis. A spectroscopic binary system, its components orbit each other every 92.94 years and are roughly as far apart from each other as the Sun and Neptune. The individual stars have visual magnitudes of 4.04 and 5.60, and spectral types B9V and A3V.
When discovered to be variable in 1970, it was classified as a Delta Scuti variable with the earliest known spectral type of any known at the time and an amplitude of 0.05 magnitudes, but it was soon realized that the nature of its variations was likely different from other Delta Scuti variables. It is now known that stars with such spectral types can have pulsations similar to those of Delta Scuti variables.
^Abt, Helmut A.; Morrell, Nidia I. (July 1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". Astrophysical Journal Supplement99: 135. Bibcode:1995ApJS...99..135A. doi:10.1086/192182.
^Veto, B.; Kovacs, G. (October 1981). "Standstill of gamma CrB". Information Bulletin on Variable Stars (2030): 1. Bibcode:1981IBVS.2030....1V.
^Lehmann, H.; Scholz, G.; Hildebrandt, G.; Yang, S. (November 1997). "The RV-variations of γ Coronae Borealis - a frequency analysis". Astronomy and Astrophysics327: 167–172. Bibcode:1997A&A...327..167L.