Empirical relationship between calcium triplet equivalent widths and [Fe/H] using Gaia photometry

<p>I present a new empirical relationship for red giant branch stars between the overall metallicity of the star and the sum of equivalent widths of the near-infrared calcium triplet (CaT) spectral lines. This method takes advantage of the all-sky photometry and astrometry of the Gaia&nbsp;mission, and the archival spectra from 2050 red giant branch stars from 18 globular clusters (-0.69&gt;[Fe/H]&gt;-2.44) acquired with the Anglo-Australian Telescope&#39;s AAOmega spectrograph.</p> <ul> <li>&lt;cluster_name&gt;.tar.gz <ul> <li>Raw and reduced spectra for 18 globular clusters (NGC104, NGC6752, NGC6809, NGC288, NGC7099, NGC362, NGC6218, NGC4590, IC4499, NGC1904, ESO452-SC06, ESO280-SC12, NGC1851, NGC6624, NGC2298, Pal 5, NGC5024, Terzan&nbsp;8, NGC5053)</li> <li>Lists of likely members</li> <li>Measured equivalent widths and radial velocities</li> </ul> </li> <li>code.tar.gz <ul> <li>running.py &ndash; calculates the equivalent widths and radial velocities of the stars from the spectra</li> <li>cat_new_params.py &ndash; calculates the best fitting empirical relationship</li> </ul> </li> <li>paper.tar.gz <ul> <li>The LaTeX source for the submitted RNAAS paper.</li> </ul> </li> </ul> <p>&nbsp;</p>