A study of the absorption-line spectra of six high-redshift quasi-stellar objects

Six QSOs, PKS 0424-131, 0457+024 (OF 097), 0824+110, 0830+115, 1226+105, and 2351-154 (OZ-187), all with z/sub e/>2, have been studied at approx.1.5 A resolution using the imagetube spectrograph attached to the 4 m Mayall reflector at Kitt Peak National Observatory. Between 26 and 139 absorption lines are found in the approx.1500 A intervals observed in each object. Table 3 contains a list of all 520 absorption lines with their relative strengths. Multiple absorption redshifts were found in each object as follows: 18 in 0424-131 (seven certain, one probable, ten possible), eight in 0457+024 (one certain, one probable, six possible), 11 in 0824+110 (four certain, two probable, five possible), 33 in 0830+115 (eight certain, 10 probable, 15 possible), four in 1226+105 (one certain, one probable, two possible), and 11 in 2351-154 (one certain, two probable, eight possible). Details of all absorption systems are given in sectionIV and Tables 4-9. Despite the relatively large number of identifications, about 60% of all of the lines remain unidentified. Thirty of the absorption systems in 0830+115 are identified with the Lyman series, including one with z/sub a/>z/sub e/.However, ther remain some strong features in this QSO and in others longward of L..cap alpha.. emission which cannot be identified under any reasonable hypothesis.In 0424-131 we find evidence for multiple line locking between low-redshift low-ionization and high-redshift high-ionization systems. More than one-quarter of the identified lines are assigned to two or more redshift systems.