Transformations between the 2MASS, SDSS, and BVI photometric systems for late‐type giants

Abstract

We present colour transformations from Two Micron All Sky Survey (2MASS) photometric system to Johnson‐Cousins system and to Sloan Digital Sky Survey (SDSS) system for late‐type giants and vice versa. The giant star sample was formed using surface gravity constraints (2 < log g ≤ 3) to Cayrel de Strobel et al.'s (2001) spectroscopic catalogue. 2MASS, SDSS and Johnson‐Cousins photometric data was taken from Cutri et al. (2003), Ofek (2008), and van Leeuwen (2007), respectively. The final sample was refined applying the following steps: (1) the data were dereddened, (2) the sample stars selected are of the highest photometric quality. We give two‐colour dependent transformations as a function of metallicity as well as independent of metallicity. The transformations provide absolute magnitudes and distance determinations which can be used in space density evaluations at relatively short distances where some or all of the SDSS magnitudes of late‐type giants are saturated (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Transformations from WISE to 2MASS, SDSS and BVI Photometric Systems: II. Transformation Equations for Red-Clump Stars

“…It is noticeable that even when the procedure used for the transformations for dwarfs was different in Bilir et al (2008Bilir et al ( , 2011a, we separated the dwarf sample into different metallicity sub-samples instead of adding a metallicity term to the transformation equations, we obtained here the same result, that is they were metallicity dependent. This dependence of the transformations on metallicity had been also confirmed in Yaz et al (2010).…”

“…As explained in Yaz et al (2010), this approach, that includes a metallicity term instead of deriving transformations for a set of stars with a metallicity range but omitting the metallicity term, can be …”

Absolute Magnitude Calibration for Red Giants Based on the Colour–Magnitude Diagrams of Galactic Clusters. III. Calibration with 2MASS

“…Accurate calibration in apparent magnitude provided accurate absolute magnitudes. The magnitudes and colours for the cluster M67 used in the calibration of M J and M K s absolute magnitudes are not original, but they are transformed from the V , B − V , and V − I data by means of the equations of Yaz et al (2010). The same case holds for the clusters NGC 188 and M68 which are used in the application of the procedure.…”

“…For the cluster M67, we transformed the V , B − V, and V − I data of Montgomery et al (1993) to (V − K s ) 0 by the following equation of Yaz et al (2010), and then we evaluated the K s 0 magnitudes by the combination of V 0 magnitudes and (V − K s ) 0 colours:…”

Colour Transformations between BVRc and g′r′i′ Photometric Systems for Giant Stars

“…However, the most accurate colours (g − V ) 0 , (g − r ) 0 and (r − i ) 0 come from the quadratic equations containing only (B − V ) 0 , or (V − R c ) 0 . The correlation coefficients given in Table 7 for inverse The transformation equations could be considered valid for the ranges of the magnitudes and colours used in the transformations: 7.10 < V 0 < 14.50, 7.30 < g 0 < 14.85,−0.20 < (B − V ) 0 < 1.41, −0.11 < (V − R c ) 0 < 0.73, −0.42 < (g − r ) 0 < 1.15, and −0.37 < (r − i ) 0 < 0.47 mag, rather larger than the ones provided by Yaz et al (2010), i.e. 0.25 < (B − V ) 0 < 1.35, 0.10 < (g − r) 0 < 0.95, and 0 < (r − i) 0 < 0.35.…”