VizieR Online Data Catalog: Spectroscopic observations on M4 AGB stars (MacLean+, 2018)
Abstract
The reduced M 4 high-resolution spectra and photometry used in this study are the same as those used in ML16 (2016MNRAS.460L..69M). Spectra were collected in 2014 August and 2015 July, using 2dF+HERMES on the AAT which provides R=28000 resolution spectra in four narrow spectral windows (Sheinis et al. 2015JATIS...1c5002S). In total, 121 targets were observed with average signal-to-noise ratio (SNR) of 70. The software package 2dfdr (AAO Software Team 2015ascl.soft05015A, v6.5) was used to reduce the spectral data for analysis. Photometry was taken from Momany et al. (2003A&A...407..303M, UBVI photometry and target IDs) and 2MASS (JHK photometry; Skrutskie et al. 2006AJ....131.1163S, Cat. VII/233). M 4 suffers from significant differential reddening, however constant reddening values were used in ML16. Here we improve upon this, with each star corrected using the reddening map of Hendricks et al. (2012AJ....144...25H). Individual corrections are included in Table 1. We found an average reddening value of E(B-V)=0.37 and a 1σ star-to-star scatter of +/-0.02. This differential reddening map, however, does not cover our entire sample, and some stars were only adjusted according to the average reddening value.
(3 data files).- Publication:
-
VizieR Online Data Catalog
- Pub Date:
- June 2022
- Bibcode:
- 2022yCat..74810373M
- Keywords:
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- Abundances;
- Clusters: globular;
- Stars: giant;
- Photometry: UBVRI;
- Photometry: infrared