EMISSION LINE DATA

Table 1. Emission line data for quasars.

There are three other quasars which belong to the same spectral class (Varshni, 1976) as 0805+046. It is convenient to consider the four quasars together. It also helps in assessing the accuracy of the reported wavelengths. We summarize the data for the three important emission lines which have been observed in these quasars in Table I. For each quasar the first row shows the reported wavelengths. Below each wavelength, where known, are indicated the equivalent width and half-width (FWHM) of the line. A few other weak emission lines have been reported, but data on these are very uncertain and, hence, these lines are not included here.

0805+046

There are three sets of measurements available. (a) Lynds and Wills (1970) spectroscopic observations were made at Kitt Peak National observatory. (b) Osmer and Smith (1976) carried out absolute spectrophotometry using the SIT-vidicon spectrometer on the 1.5m telescope at CTIO. (c) Jian-sheng et al. (1981) obtained the spectra of this quasar with the AAT at 2 Å resolution.

0138-381

Two sets of data are available. (a) It was first observed by Osmer and Smith (1976) who carried out absolute spectrophotometry. (b) Whelan et al. (1979) observed it using the AAT in the wavelength region 4550-6400 Å. As Table I shows, these authors found the equivalent widths of the three lines in Table I to be a factor two lower than those determined previously by Osmer and Smith (1976). Subsequent absolute spectrophotometry by Whelan et al. (1979) using the Boksenberg IPCS confirmed Osmer and Smith's original value for line No.1 but yielded a value for the line No.3 close to what they had found originally. From the available evidence it would appear that there was a large change in the relative intensities of line Nos.1 and 3 between the times of observations of Osmer and Smith (1976) and those of Whelan et al. (1979). Such a change is readily understandable on the PLS model (Varshni, 1975a, 1979).

0316-203

The observations are due to White et al. (1980). Set (a) was obtained on 22 November, 1976 with a red sensitive image tube and set (b) on 17 October, 1978 with a blue sensitive image tube. There are large differences in the equivalent widths and FWHM's of the two sets. Line No. 1 is badly `eaten' by absorption lines and the wavelength of its peak is poorly determined.

1124+571

The quoted values are from Walsh et al. (1984) whose observations were made in April 1981 using the Multiple Mirror Telescope intermediate-dispersion spectrograph with a 300 line mm (1) grating used in first order, and an image-intensified, photon-counting reticon detector. The wavelength and equivalent width of line No.2 may have considerable uncertainty.

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