Astron. Astrophys. 332, 503-513 (1998)

Appendix A: notes on individual objects and comparison with previous NIR photometry

PKS 0208-512. The H band image of this z = 1.003 FSRQ shows quite a smooth morphology. The host galaxy is marginally resolved. Unfortunately, this source has no reference stars in the observed field. The profile fit shown in Fig. 2 has been derived using a PSF estimated from field stars in the frames taken as close as possible in time and with similar seeing conditions. With these assumptions, the implied host galaxy is the most luminous in the FSRQ sample (M(H) = LILLI30.3). However, due to the uncertainty in the PSF shape, we have omitted this FSRQ from the statistical analysis and discussion. No previous NIR photometry was found for PKS 0208-512.

PKS 0336-019. This source at z = 0.852 remains unresolved. Our H band magnitude in a aperture (16.39) is over a magnitude fainter than that found in the literature (Table 5).

Table 5. The range of NIR photometry from the literature.

PKS 0403-132. The H band image of this z = 0.571 source is marginally resolved, elongated roughly NE-SW, with possible fainter extended emission to N. Note also several other sources in the field, that may be companions. Our H band magnitude (14.97) agrees well with literature photometry (Table 5). Rönnback et al. (1996) studied this source as part of their R band survey of intermediate redshift RLQs. They derive M(H,host) and R(e) = 25 kpc. Both values are in excellent agreement with our results (see Table 3).

PKS 0405-123. This source at z = 0.574 is well resolved in our image. The host galaxy is elongated roughly N-S. Our photometry (H = 13.33) is slightly fainter, but in overall agreement with literature photometry (Table  5).

PKS 0420-014. This high redshift (z = 0.915) source is surprisingly well resolved in our image. There is a large range in the magnitudes quoted for this object that reflects the rather large flux variability of this object (Table 5).

PKS 0440-003. The H band image of this z = 0.844 source remains unresolved. No previous NIR photometry was found for PKS 0440-003.

PKS 0454-463. This z = 0.858 source is unresolved in our image. No previous NIR photometry was found for PKS 0454-463.

PKS 0605-085. The redshift (z = 0.872) was derived from one strong broad emission line interpreted as MgII 2800 Å  and a rather faint emission line of [NeV]3426 Å  (Wills 1976). In spite of the high redshift, the H band image of PKS 0605-085 appears well resolved. There is, however, a close companion object to SW, likely to be a red M-type galactic star (Wills 1976). The extended (possibly dust) emission from this star makes the derivation of the luminosity profile of PKS 0605-085 problematic, and we prefer only to show the profile, obtained by excluding the sector containing the companion, without attempting to model it. No previous NIR photometry was found for PKS 0605-085.

PKS 0637-752. This z = 0.654 source is marginally resolved in our image. There is another object N of it, with possible extension from PKS 0637-752 toward it, suggesting a physical companion. There are other, bright sources toward NE and S, and a jet-like feature to SE. Our H band magnitude (14.79) is over a magnitude fainter than that found in the literature (Table  5).

PKS 0736+017. This nearby well-studied source (z = 0.191) is well resolved in our image. The host reveals a rather smooth morphology. Our H band photometry (H = 13.66) agrees quite well with most previous studies (Table 5). T96 could not discriminate between a bulge or a disk fit for this source, although their disk model gave a slightly better fit. Their bulge (disk) fit resulted in M(H,host) = -26.1 (-24.9), M(H,nuc) = -27.3 (-27.0), LN/LG = 3.2 (10.2), and R(e) = 29 (38) kpc. Our result (Table 3) agrees reasonably well for the host and nuclear luminosity (both M(H) = -26.2), but we find much lower LN/LG ratio (1.0) and much lower effective radius (R(e) = 3.2 kpc). In the optical, the source has been imaged with sub-arcsec resolution and found to be well fit by a point source and an elliptical galaxy of M(R) = -23.5 and R(e) = 15 kpc (Falomo 1996). This yields R-H color of the host of 2.7.

PKS 1055+018. The H band image of this z = 0.888 source remains unresolved. Our H band magnitude (15.19) is somewhat fainter than that found in the literature (Table 5).

PKS 1226+023 = 3C 273. This extensively studied high-luminosity AGN at z = 0.158 is well resolved and shows quite a smooth morphology. Our photometry (H = 10.92) agrees well with most previous studies (Table 5). Early optical studies of the host galaxy of 3C 273 include Wyckoff et al. (1980), Tyson, Baum & Kreidl (1982) and Hutchings & Neff (1991), who found M(V) -22.8, -24.0, and -23.2, respectively, for the host. More recently, McLeod & Rieke (1994a) derived M(H,host) = -26.8, and Bahcall et al. (1997) present analysis of the 3C 273 host as part of their sample of 20 nearby luminous quasars observed with the HST. From a 2-D fit with a point source and a bulge, they derive M(V,host) = -23.6. Our result (Table 3) of M(H,host) = -27.0 is in good agreement with all these previous studies.

PKS 1253-055 = 3C 279. The H band image of this well-studied source at z = 0.538 was taken under poor seeing conditions and remains unresolved. Our H band magnitude (12.92) agrees reasonably well with previous photometry (Table 5) of this strongly variable quasar. Veron-Cetty & Woltjer (1990) derived M(V) = -25.0 for the host galaxy of 3C 279. For typical galaxy colour, this would indicate M(H) -28.0, but the host remains unresolved in our observations with an upper limit of M(H) .

PKS 1504-166. This source at z = 0.876 remains unresolved in our image. The target lies near the border of the array, where the surrounding region is quite noisy. No previous NIR photometry was found for PKS 1504-166.

PKS 1510-089. The H band image of this z = 0.361 source remains unresolved. Our H band magnitude (13.29) is much brighter than in most previous studies (Table 5). Veron-Cetty & Woltjer (1990) derived M(V) = -22.6 for the host galaxy of PKS 1510-089, indicating for typical galaxy colour M(H) -25.5 but the host remains unresolved in our data, probably due to poor seeing during the observations. An upper limit of M(H) = -26.0 is derived.

PKS 1954-388. The H band image of this z = 0.626 source is resolved, with a possible companion to NW. Our H band photometry (14.15) agrees reasonably well with literature (Table 5).

PKS 2128-123. This source at z = 0.501 is marginally resolved in our image. There is a possible companion to NE. Our H band magnitude (14.32) agrees well with literature (Table 5). Disney et al. (1995) have studied PKS 2128-123 with the HST. They found M(R,host) = -23.7, M(R,nuc) = -26.6, LN/LG = 13.5 and R(e) = 37.4 kpc. Our result (Table 3) indicates M(H,host) = -25.1, LN/LG = 44.0 and R(e) = 16 kpc. While the host magnitude we derive is 1 mag fainter than expected from the I-band for normal galaxy colours, this difference is not unreasonable, taking into account all the uncertainties in the derivation of the parameters for the marginally resolved hosts.

PKS 2145+067. The H band image of this z = 0.990 source is marginally resolved. Our H band magnitude (14.47) agrees well with literature (Table 5).

PKS 2243-123. This source at z = 0.630 is marginally resolved in our image. There is a possible companion source to SW. Our H band magnitude (14.91) is in excellent agreement with literature (Table 5).

PKS 2345-167. The H band image of this source at z = 0.576 is clearly resolved. Our H band photometry (13.43) is over 2 magnitudes brighter than found in the literature (Table 5).

© European Southern Observatory (ESO) 1998

Online publication: March 23, 1998
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