2008/12/28 by Lutz, R., Schuh, S., Silvotti, R. +2
#Astrophysics (astro-ph) #FOS: Physical sciences
paper · doi:10.48550/arxiv.0812.4859
Pulsating subdwarf B stars oscillate in short-period p-modes or long-period g-modes. HS 0702 + 6043 is one of currently three objects known to show characteristics of both types and hence is classified as hybrid pulsator. We briefly present our analysis of the g-mode domain of this star, but focus on first results from long-term photometric monitoring in particular of the p-mode oscillations. We present a high-resolution frequency spectrum, and report on our efforts to construct a multi-season O--C diagram. Additionally to the standard (although nontrivial) exercise in asteroseismology to probe the instantaneous inner structure of a star, measured changes in the pulsation frequencies as derived from an O--C diagram can be compared to theoretical evolutionary timescales. Within the EXOTIME program, we also use this same data to search for planetary companions around extreme horizontal branch objects.