| |< | | < | | ^ | | > | | >| |
Q 1421+331
V = 16.7; z = 1.906; exp = 3600 s; coverage = 3818.6-6316.9
This QSO has been the subject of several studies (Weymann et al. 1979; Uomoto 1984; Foltz et al. 1986; Caulet 1989; SS92), which are described in SS92. The HIRES spectrum confirms complex C IV systems at z = 1.584, 1.717, (Caulet 1989) and 1.759 (Foltz et al. 1986). A previously unreported Mg II doublet at z = 0.8431 was discovered in the HIRES spectrum. Though the z = 0.4564 absorber was clearly detected in the HIRES spectrum, it was badly affected by poor signal to noise at the detector edge. It has not been included in this work.
z=0.843247 |DATA & VOIGT PROFILES| |EWs & AOD COLUMNS| |VP PARAMETERS|
There is no previous report of this system in the literature. However, Uomoto (1984) reported an unidentified "moderate, broad" line and an unidentified "weak" line in his spectrum. These two lines correspond to Fe II 2600 and 2374 at this redshift, respectively. The system was fit with a single VP component. Absorption was seen in all observed Fe II transitions and also in the Mg I transition. The Mg II to Fe II ratio of both the apparent column densities and the VP column densities is less than unity, which is not common. This may be indicative of an enhancement of iron group (Type Ia SN origins) relative to alpha-group (Type II SN origins) elements. Alternatively, the observed ratio log N(MgII)/N(FeII) = -0.35, and the ratio log N(MgII)/N(MgI) = 1.52, are somewhat consistent with collisionally ionized gas with T ~30,000 K, assuming solar abundances (e.g. Tytler et al. 1987). Thus, it is possible that the absorption arises in an H II region not unlike those found in the Galaxy. Depletion in H I photoionized gas, on the other hand, tends to increase the Mg II to Fe II column density ratio, which is 1.2 for solar abundances in the case of no depletion (Tytler et al. 1987). High resolution spectra of highly ionized species, especially C IV, N V, and O VI, and of the neutral hydrogen column density, could be very instrumental for obtaining a better appreciation of this absorption system. The Ca II 3934, 3969 doublet was not covered by the HIRES format. The Mn II triplet showed no absorption to the EW(rest) limits given in Table 3.44.
z=0.902871 |DATA & VOIGT PROFILES| |EWs & AOD COLUMNS| |VP PARAMETERS|This system was first reported by Uomoto (1984). The full profile was fit with a total of ten VP components. Fe II was present in each, whereas VP components of Mg I were found only in components six and seven. There are two subsystems based upon the ewregion algorithm, though the profile is more suggestive of three. In the strongest subsystem, the Fe II transitions reveal a "disk--like" profile, or the characteristic of organized motion with a density gradient along the line of sight. Mg I absorption is seen only in this subsystem, and it also exhibits a blueward asymmetry. The Mn II 2594 transition, tentatively reported by Uomoto (1984), is not seen in the HIRES spectrum, nor is a nearby unidentified absorption feature seen. The Ca II 3934, 3969 doublet was not covered by the HIRES format. The Mn II triplet showed no absorption to the EW(rest) limits given in Table 3.45.
z=1.172609 |DATA & VOIGT PROFILES| |EWs & AOD COLUMNS| |VP PARAMETERS|This system was also first reported by Uomoto (1984). The full profile was fit with a total of seven VP components over a single system (no subsystems). The profile is quite symmetric, though exhibits three strong centers of higher column density gas. Mg I has been detected in these three regions. The Ca II 3934, 3969 doublet and the Mn II 2594 transition were not covered by the HIRES format. The Mn II triplet showed no absorption to the EW(rest) limits given in Table 3.46.
|PREVIOUS QSO| |NEXT QSO| | QSO LISTING | |TABLE OF CONTENTS| |CWC HOME|