M30 stars Teff and [M/H]

We apply spectral synthesis methods to spectra observed with the GIRAFFE spectrograph on the VLT to estimate abundances of Mg, Ti, Fe, and Ba in stars in the metal-poor globular cluster M 30. To the abundances we fit trends of abundances predicted by stellar evolution models assuming different efficiencies of additional transport or mixing processes.

The fitting procedure attempts to take into account the effects of parameter-dependent systematic errors in the derived abundances. We find that the parameter T_0_, which describes the efficiency of additional transport or mixing processes, can almost certainly be constrained to the narrow range log_10_(T_0_/[K]) between 6.09 and 6.2. This corresponds to decreased abundances for stars at the main sequence turn-off point compared to the red giant branch by 0.2dex for Mg, 0.1dex for Fe, and 0.07dex for Ti.