Near infrared spectrum of the z = 5.77 quasar SDS J0836+0054

Near infrared spectrum of the z = 5.77 quasar SDS J0836+0054. The line of C III] 1909 in the mid infrared spectrum, obtained with FLAMINGOS on Gemini South, was used to derive a more accurate value for the redshift. The particular red slope of the spectrum is illustrated by the comparison with a composite quasar spectrum (see dotted line). The quasar has a J magnitude of 17.89 +/- 0.05.