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5.6.2 k-correction

The magnitudes and surface brightnesses were also k-corrected. For Johnson B and U we used the k-correction given by Pence (1976), see Table [*]. We used a linear interpolation in $z_{\rm hel}$. All the HydraI galaxies have $z_{\rm hel}$ in the range 0.00-0.02. For Gunn r we used the k-correction $2.5\log(1+{z_{\rm hel}})$ from JFK92. The value at ${z_{\rm hel}}= 0.02$ is listed in Table [*] for comparison with Johnson B and U. For the 8 galaxies without a measured redshift, the cluster mean of $cz_{\rm hel}$ = 3718 km/s (Zabludoff et al. 1990) was used. The k-corrections for the HydraI galaxies are given in Table [*].

Table: k-corrections for E and S0 Galaxies
Filter k-correction at ${z_{\rm hel}}= 0.02$ Reference
Gunn r 0.022 JFK92
Johnson B 0.092 Pence (1976)
Johnson U 0.065 Pence (1976)
Notes: The values from Pence (1976) assume a galactic extinction at the galactic poles of zero.

Properties of E and S0 Galaxies in the Clusters HydraI and Coma
Master's Thesis, University of Copenhagen, July 1997

Bo Milvang-Jensen (