Extended Data Fig. 1: Example spectra of two member galaxies of XLSSC 122.
From: Spectroscopic confirmation of a mature galaxy cluster at a redshift of 2
a, The brightest cluster galaxy (ID 526) as the black line with error bars with the best-fitting, redshifted galaxy template shown in red (see Methods). b, A fainter cluster member with strong emission lines (ID 1141) as the black line with error bars. Error bars indicate the 1-sigma measurement uncertainty. The vertical dashed lines show the observed frame location of [O ii] 3,727 Å, Hβ 4,861 Å and [O iii] 5,007 Å at a redshift of 1.963.