A New Class of Variable Stars

Gemini South spectra for three BLAPs. Best fits of stellar atmosphere models are shown with red lines. Effective temperatures, surface gravities, and helium abundances derived for these stars are similar to the values obtained from spectra for the prototype object previously studied. Credit: Gemini Observatory/AURA/NSF.

Astronomers using the Multi-Object Spectrograph (GMOS) on the Gemini South telescope have confirmed a new class of variable stars called Blue Large-Amplitude Pulsators (BLAPs). Pawel Pietrukowicz (Warsaw University Observatory, Poland) led the study as part of the Optical Gravitational Lensing Experiment (OGLE), a variability sky survey conducted on the 1.3-meter Warsaw Telescope at Las Campanas Observatory, Chile. For more details see the Gemini webfeature.