English

The Metallicity Gradient of the Old Galactic Bulge Population

Solar and Stellar Astrophysics 2015-06-22 v1

Abstract

Understanding the structure, formation and evolution of the Galactic Bulge requires the proper determination of spatial metallicity gradients in both the radial and vertical directions. RR Lyrae pulsators, known to be excellent distance indicators, may hold the key to determining these gradients. Jurcsik & Kovacs (1996) has shown that RR Lyrae light curves and the phase difference of their Fourier decomposition, {\phi}31, can be used to estimate photometric metallicities. The existence of galactic bulge metallicity gradients is a currently debated topic that would help pinpoint the Galaxy's formation and evolution. A recent study of the OGLE-III Galactic Bulge RR Lyrae Population by Pietrukowicz et al. (2012) suggests that the spatial distribution is uniform. We investigate how small a gradient would be detectable within the current S/N levels of the present data set, given the random and systematic errors associated with the derivation of a photometric metallicity versus spatial position relationship.

Keywords

Cite

@article{arxiv.1409.2278,
  title  = {The Metallicity Gradient of the Old Galactic Bulge Population},
  author = {Sara Alejandra Sans Fuentes and Joris De Ridder},
  journal= {arXiv preprint arXiv:1409.2278},
  year   = {2015}
}

Comments

Proc. of the workshop "Asteroseismology of stellar populations in the Milky Way" (Sesto, 22-26 July 2013), Astrophysics and Space Science Proceedings, (eds. A. Miglio, L. Girardi, P. Eggenberger, J. Montalban)