RR Lyrae: the zero point of temperature and magnitude scales.

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

8

Stars: Fundamental Parameters, Stars: Oscillations, Stars: Variables: Others

Scientific paper

We find that the position in the HR diagram of the RR Lyrae variables of type ab is strictly related to properties defined in the period-amplitude plane: that is, both temperature and V magnitude of the static star are tightly correlated with blue amplitude and period. Using this pulsational approach, we show that the equilibrium temperature derived by the Baade-Wesselink (BW) method, using V and K bands, connects observational data with both pulsational and evolutionary theories in a self consistent scenario for an original helium of Y=0.23 . In contrast, we wholly confirm the inconsistency between temperature and luminosity level as derived by the BW procedure with the luminosity being wrong. We use the pulsational properties to compare the distance modulus derived by RRab variables with that obtained by the isochrone fitting procedure for a sample of galactic globular clusters (GGCs). We find a convergence to within about 0.1mag of uncertainty: in turn, this means that ages derived by both the {DELTA}V(ZAHB-TO) and the {DELTA}(B-V) methods agree to within approximately 2Gyr. Finally, we point out the following: a) the metal poor GGCs M92, M68 and M15 appear coeval (20Gyr old); b) an age spread of =~6Gyr is found in our sample of clusters.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

RR Lyrae: the zero point of temperature and magnitude scales. 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: the zero point of temperature and magnitude scales., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and RR Lyrae: the zero point of temperature and magnitude scales. will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1153361

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.