Journal
ASTROPHYSICAL JOURNAL
Volume 808, Issue 1, Pages -Publisher
IOP PUBLISHING LTD
DOI: 10.1088/0004-637X/808/1/50
Keywords
stars: evolution; stars: horizontal-branch; stars: oscillations; stars: variables: RR Lyrae
Categories
Funding
- PRIN-INAF Tracing the formation and evolution of the Galactic halo with VST
- PRIN-INAF The M4 Core Project with Hubble Space Telescope
- PRIN-MIUR Chemical and dynamical evolution of the Milky Way and Local Group galaxies [2010LY5N2T]
- Carnegie Observatories visitor program
Ask authors/readers for more resources
We present new nonlinear, time-dependent convective hydrodynamical models of RR Lyrae stars computed assuming a constant helium-to-metal enrichment ratio and a broad range in metal abundances (Z = 0.0001-0.02). The stellar masses and luminosities adopted to construct the pulsation models were fixed according to detailed central He-burning horizontal-branch evolutionary models. The pulsation models cover a broad range in stellar luminosity and effective temperatures and the modal stability is investigated for both fundamental (FU) and first overtone polsators (FOs). We predict the topology of the instability strip (IS) as a function of the metal content and new analytical relations for the edges of the IS in the observational plane. Moreover, a new analytical relation to constrain the pulsation mass of double pulsators as a function of the period ratio and the metal content is provided. We derive new Period-Radius-Metallicity relations for FU and FO pulsators. They agree quite well with similar empirical and theoretical relations in the literature. From the predicted bolometric light curves, transformed into optical (UBVRI) and near-infrared (NIR; JHK) bands, we compute the intensity-averaged mean magnitudes along the entire pulsation cycle and in turn new and homogenous metal-dependent (RIJHK) Period-Luminosity relations. Moreover, we compute new dual and triple-band optical, optical-NIR, and NIR Period-Wesenheit-Metallicity relations. Interestingly, we find that the optical Period-W(V, B-V) is independent of the metal content and that the accuracy of individual distances is a balance between the adopted diagnostics and the precision of photometric and spectroscopic data sets.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available