Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-07-05
Astronomy and Astrophysics
Astrophysics
16 pages, submitted to Astrophysical Journal Letters
Scientific paper
We present a catalog of 15 RR Lyrae variable stars in the recently discovered Bootes galaxy -- the most metal-poor simple stellar population with measured RR Lyrae stars. The pulsational properties of the RR Lyrae conform closely to period-abundance trends extrapolated from more metal-rich populations and we estimate the distance of Bootes to be (m-M)_0=18.96+-0.12. The average period (0.69 days), the ratio of type c to type ab pulsators (0.53) and the RRab period shift (-0.07) indicate an Oosterhoff II classification for Bootes, a marked contrast to the other dSph galaxies, which are Oosterhoff intermediate. This supports the contention that the Oosterhoff dichotomy is a continuum -- that RR Lyrae properties, to first order, vary smoothly with abundance. The dSph galaxies are not distinct from the Galactic globular clusters, but bridge the Oosterhoff gap. The absence of any anomalous Cepheids in Bootes could indicate the lack of an intermediate age population.
No associations
LandOfFree
RR Lyrae Stars in the Bootes dSph does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with RR Lyrae Stars in the Bootes dSph, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and RR Lyrae Stars in the Bootes dSph will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-45652