HD molecular lines in an absorption system at redshift z=2.3377

Having analyzed the spectrum of the quasar PKS 1232+0.82 taken by Petitjean et al. (2000), we identified HD molecular lines in an absorption system at redshift z = 2.3377. We estimated the column density of HD molecules in this system, N(HD) = (1-4) x 10(14) cm(-2). The excitation temperature of the first rotational level J=1 relative to the ground state J=0 is T-ex = 70 +/-7 K. As far as we know, this is the first detection of HD molecules at high redshift. (C) 2001 MAIK Nauka/Interperiodica.