THE ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 112:415421, 1997 October
© 1997. The American Astronomical Society. All rights reserved. Printed in U.S.A.

Hubble Space Telescope Snapshot Survey of 3CR Radio Source Counterparts. II. Radio Galaxies with z > 0.5

PATRICK J. MCCARTHY, ¹ GEORGE K. MILEY, ² SIGRID DE KOFF, ^{2, 3} STEFI A. BAUM, ³ WILLIAM B. SPARKS, ³ DANIEL GOLOMBEK, ³ JOHN BIRETTA, ³ AND FERDINANDO MACCHETTO ³

Received 1996 June 24; accepted 1997 April 29

ABSTRACT

     We present images of 51 3CR radio galaxies with 0.5 < z < 2.5 obtained in the snapshot mode with the Hubble Space Telescope. The images are short exposures with the Planetary Camera and the F702W filter. A wide range of morphologies and surface brightness are seen on subarcsecond scales. Some are very strongly nucleated, and their light is most likely dominated by the nonstellar nucleus. Several galaxies have close companions or multiple components, while others have a close agreement between their optical/UV and radio sizes and orientations. These latter objects are primarily steep-spectrum doubles with angular sizes less than 5.

Subject headings: galaxies: structureradio continuum: galaxiessurveys

FOOTNOTES

     ¹ The Observatories of the Carnegie Institution, 813 Santa Barbara Street, Pasadena, CA 91101.

     ² Sterrewacht Leiden, Huygens Laboratorium, P.O. Box 9513, 2300 RA Leiden, The Netherlands.

     ³ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218.

§1. INTRODUCTION

     The morphologies of radio galaxies at large redshifts have been of considerable interest from the time that they were first observed in significant numbers (see, e.g., Lilly & Longair 1983; Spinrad & Djorgovski 1984a, 1984b). The apparent change in morphology with redshift that occurs at z 0.60.8 was tentatively identified as the result of galaxy interactions and bursts of star formation (Lilly & Longair 1983; Djorgovski et al. 1987). The dramatic change in the UV to visible colors, relative to present-day early-type galaxies, that accompanies the morphological evolution loaned strong support to the starburst origin for the change in radio galaxy hosts at high redshifts. The discovery of the alignment between the radio and visible/UV axes of radio galaxies at intermediate and high redshifts (McCarthy et al. 1987; Chambers, Miley, & van Breugel 1988) altered the situation substantially. Understanding the Alignment Effect has become the focus of considerable effort in recent years. The status of observational and theoretical work on this subject is summarized in McCarthy (1993), Best, Longair, & Rottgering (1996a), and Rush et al. (1997).

     One of the primary capabilities of the refurbished Hubble Space Telescope (HST) is its ability to reveal morphologies at subarcsecond levels, even in very faint objects. HST observations have had a significant impact on this field and will continue to do so. Deep images of the most distant radio galaxies (e.g., 4C 41.17: Miley et al. 1992; van Breugel et al. 1996) have revealed detailed correspondences between the radio and rest-frame UV morphologies to a degree that is currently not possible from ground-based observations. A number of other high-redshift radio galaxies have been observed in detail with HST with widely varying results (see, e.g., Longair, Best, & Rottgering 1995; Best et al. 1996a, 1996b; Rush et al. 1997). Some objects have fairly simply morphologies (e.g., 3C 65), while others (e.g., 3C 368) are quite complex.

     Unbiased samples of significant size are essential for statistical studies of the apparent evolution of the properties of radio galaxies or any other class of astronomical object. The large demand on HST makes it problematical to carry out large survey programs in the usual observing mode. The snapshot programs provide a means for performing surveys of significant numbers of objects in a timely manner. The limitation imposed by the snapshot program is that the exposure times are short; however, the sensitivity of WFPC-2 and the compact structures present in these galaxies make snapshot observations quite valuable nonetheless. The data presented here probe the morphologies of distant radio galaxies on scales <2 to 3 and to a surface brightness level of typically 23 mag arcsec^-2.

     We have carried out a snapshot survey of a large fraction of the complete 3CR catalog. This survey is described in some detail in de Koff et al. (1996; hereafter Paper I), and we will not repeat that discussion here. In this paper we present the results for the high-redshift radio galaxies in the 3CR sample, including only those with z > 0.5. The z < 0.1 galaxies and the 3CR quasars will be presented by Baum et al. (1997) and Lehnert et al. (1997), respectively. The compact steep spectrum sources are discussed by de Vries et al. (1997).

§2. SAMPLE DEFINITION, OBSERVATIONS, AND PROCESSING

     Our objects are drawn from the 3CR sample as defined by Bennett (1962) and compiled by Spinrad and coworkers (see, e.g., Spinrad et al. 1985 and unpublished updates; Djorgovski et al. 1988; Strom et al. 1990). This paper considers only those objects from the 3CR identified with galaxies having measured redshifts greater than 0.5. There are currently 75 galaxies that meet these criteria. We have observed 58 (77%) of these with the Planetary Camera II on HST. In Figure 1 we show the redshift distribution of the galaxies observed in this program and the galaxies from Paper I. The redshift distribution of the complete 3CR galaxy sample is shown for comparison.

Fig. 1

     The observations were all made with the F702W filter which spans the range 60008200. The requested exposure times were 300 s. Some of the observations were split into two exposures to facilitate cosmic-ray removal, resulting in two 140 s exposures. Others were observed for a single 300 s exposure. All of the exposures were made in the fine lock mode with the target centered in the Planetary Camera relay of the WFPC-2 (Burrows et al. 1995; Trauger et al. 1994). The details of the basic image processing and cosmic-ray removal are described in Paper I.

     The basic parameters of each observation are listed in Table 1. The calibration of the instrumental magnitudes was performed with the same zero-point values given in Paper I. For each object, we measured magnitudes in two circular apertures, one 2 in diameter, the other 4.

§3. RESULTS

§3.1. Detection Rates and Sensitivity

     Despite the constant exposure time and instrumental zero point, there is a significant dispersion in the detection limit from exposure to exposure. This arose from the variable sky background due to sunlight scattered by Earth's limb. The effective background levels varied from 23.5 to 21 magnitudes per square arcsecond, with the typical value being 23 mag arcsec^-2.

     Of the 58 objects from our sample that were observed, 43 were well detected, eight were marginally detected, and seven were not detected at all. The galaxies that were not detected (3C 68.2, z = 1.575; 3C 255, z = 1.355; 3C 257, z = 2.474; 3C 294, z = 1.786; 3C 326.1, z = 1.824; 3C 437, z = 1.48; 3C 470, z = 1.65) or were only marginally detected (e.g., 3C 225A, z = 1.56; 3C 454.1, z = 1.841) were primarily those at the largest redshifts. The nondetections are not included in the histogram in Figure 1. We give the derived positions and magnitudes for all of the detected objects in Table 2. For objects with close companions or multiple components, we list each component, beginning with what we believe to be the correct identification for the radio source. There are only one or two cases (e.g., 3C 356) for which there is any ambiguity as to which object is the correct identification.

     The galaxies that were well detected show a wide range of morphologies. Several are very strongly nucleated, and their light is most likely dominated by a nonstellar nucleus. This is almost certainly the case for the N-type galaxies 3C 22, 3C 208.1, and 3C 325. Several galaxies have close companions (e.g., 3C 54, 3C 55, 3C 247) or multiple components (e.g., 3C 194, 3C 210), while others have a close agreement between their optical and radio sizes and orientations (e.g., 3C 124, 3C 266, 3C 305.1). These latter objects are primarily steep-spectrum doubles with angular sizes less than 5, which supports the connection between the alignment effect and source size suggested by Best et al. (1996a).

     The 3CR galaxies have strong forbidden lines, and these lines make significant contributions to the observed structures in our F702W images for a number of the objects in our sample. The [O II] 3727 doublet is the strongest line within the F702W bandpass for the objects in the redshift range 0.6 < z < 1.22. There is a small interval in redshift, 0.5 < z < 0.63, for which [O III] 5007, 4959 falls within the F702W filter, and for objects in this redshift range, the line contamination can be quite severe. Indeed, line-free and [O III] 5007 images of 3C 330 (McCarthy et al. 1997) obtained with the linear ramp filter on HST show that most of the extended structure seen in our F702W image arises from line contamination. For the bulk of the objects, the contamination is due primarily to [O II] 3727, [Ne III] 3869, 3967, and [Ne V] 3426, 3346. The [Ne III] and [Ne V] lines contribute a flux that is 1/2 that of [O II] 3727 in the typical radio galaxy (see, e.g., McCarthy 1993; McCarthy & Lawrence 1996), although some objects (e.g., 3C 356) can have [Ne V] + [Ne III] > [O II] 3727.

     In Table 2 we give the rest-frame equivalent width of [O II] 3727 for many of the objects in our sample. Since the F702W filter is roughly 2200 Å wide, only lines with W(obs) > 500 will make large contributions. While such lines are rare (as Table 2 shows), we have very little information concerning the maximum equivalent widths of off-nuclear emission lines at HST resolution. The 3CR LRF snapshot survey will provide some information on this at low and intermediate redshifts.

§3.2. Presentation of the Data

     We show gray-scale images and contours for all the detected objects in Figures 219 (Plates 320). For each object we show a 45 × 45 image with north at the top and east to the left. The coordinate scales in the contour panels on the right often have small offsets. The coordinates listed in Table 3 were determined from the full images and are more accurate.

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9

Fig. 10

Fig. 11

Fig. 12

Fig. 13

Fig. 14

Fig. 15

Fig. 16

Fig. 17

Fig. 18

Fig. 19

§3.3. Notes on Individual Objects

     We briefly describe the morphologies of many of the objects in our sample. Where there is a strong connection to the radio, we note the source of the radio maps. Original source citations for radio maps for nearly all of these objects can be found in McCarthy, van Breugel, & Kapahi (1991) or McCarthy, Spinrad, & van Breugel (1995).

     3C 6.1 (z = 0.840; Fig. 2).The galaxy is well detected and is compact. The contour map shows extensions at the lower isophots in position angle (P.A.) 30°, roughly equal to that of the radio axis (Pooley & Henbest 1974). There is a faint companion object at , = (+07, + 1).

     3C 13.0 (z = 1.351; Fig. 2).The identification is well detected and is extended over nearly 4. There are two faint arm or tail-like structures to the south and east of the nucleus. The radio source is a 28 double oriented in P.A. 145°. The extended emission in both the nucleus and on the 1 scale is aligned with the radio axis.

     3C 22 (z = 0.937; Fig. 2).This compact galaxy has a extension of 05 from the nucleus in P.A. 87°, 16° from the axis of the 24 double radio source. Near-IR spectra (McCarthy et al. 1993; Rawlings et al. 1995; Evans 1996) reveal broad H emission, which suggests that this source is a moderately obscured quasar. The near-IR colors (Dunlop & Peacock 1993) of the identification and its variability (Walsh et al. 1985) also suggest a significant nonstellar contribution. A case for 3C 22 being a reddened quasar is made in Rawlings et al. (1995).

     3C 34 (z = 0.689; Fig. 3).The object lies in a compact cluster of galaxies (McCarthy et al. 1995), several of which are detected in our image. The central galaxy is diffuse with a lower surface brightness than most of the galaxies in our sample. Deeper HST images are given in Best et al. (1996b).

     3C 36 (z = 1.301; Fig. 3).This faint galaxy is compact, and only a central nuclear component is detected in our image.

     3C 41 (z = 0.794; Fig. 3).This galaxy is also compact but has some extended structure. A faint companion lies to the southeast at , = 25,15.

     3C 44 (z = 0.660; Fig. 4).This galaxy lies in a cluster as shown by Spinrad (1986) and McCarthy et al. (1995). The radio galaxy is either composed of two components oriented north-south or, more likely, is bisected by a dust lane running east-west. The radio source is a large double with small bends (van Breugel & McCarthy 1997).

     3C 54 (z = 0.8274; Fig. 4).The identification has a compact nucleus with an extension to the southwest in P.A. 220°. There is a compact object near the end of the 2 extension from the nucleus. It is unclear if the extension is a bridge, tidal tail, or jet. There is another companion object a few arcseconds to the southeast. The radio source is a large double oriented in P.A. 205° (Longair 1975).

     3C 55 (z = 0.7348; Fig. 4).This object resolves into two components separated by 08 and oriented in P.A. 115°, roughly along the radio axis. The western component lies within 05 (see Table 3) of the core positions reported in Fernini et al. (1993).

     3C 65 (z = 1.176; Fig. 5).The galaxy is faint and compact with a hint of extended structure. There is a faint companion located 2 west.

     3C 107 (z = 0.785; Fig. 5).The galaxy is resolved and has a component located 04 west in P.A. 115°.

     3C 114 (z = 0.815; Fig. 5).This low surface brightness galaxy is poorly detected in our image. We see a faint compact nucleus with several clumps within the central few arcseconds.

     3C 124 (z = 1.083; Fig. 6).The galaxy is very extended with a highly curved morphology. The galaxy can be traced to 3 and is aligned with the axis of the 5 double radio source. A 5 GHz VLA map by van Breugel et al. shows a weak core at = +01°15212, coincident with the gap in seen in the HST image (within the astrometric uncertainties). This galaxy, 3C 266, and 3C 305.1 are all similar in their morphologies, and all are strikingly different from the typical compact morphology seen in most of the images (e.g., 3C 107).

     3C 169.1 (z = 0.633; Figs. 6 and 7).There are two galaxies in this system, both with extended structure. The radio source host (southeast object) has a clear extension to the east and has a number of faint clumps within the central arcsecond. The two components lie along the radio axis, and the companion object has an extension pointing toward the radio galaxy. Spectroscopy by McCarthy, Baum, & Spinrad (1996) shows that the northwest object is blueshifted relative to the radio galaxy by 1000 km s^-1.

     3C 172 (z = 0.5191; Figs. 6 and 7).This is a complex system with four objects detected in our image, one of which is stellar. The galaxy located at , = -3.5, +3.5 in Figure 7 is the accepted identification, and we concur, even though the stellar object lies along the radio axis. An [O II] 3727 image in McCarthy et al. (1995) shows extended emission that is coincident with host galaxy and extends toward the stellar object to the southwest. Long-slit spectra confirm that the bulk of the line emission is associated with the northern galaxy. There are two galaxies lying to the southwest that appear to be associated with 3C 172, and they lie along the axis of the radio source. The image in Figure 6 is centered on the host galaxy.

     3C 184 (z = 0.994; Fig. 8).The galaxy is extended over 1 in P.A. 88°, close to the radio source axis. This image has a strong contribution from [O II] 3727, and so the extended structure may be dominated by line emission. There is a compact companion galaxy 17 east in P.A. 102°, essentially the same as the radio P.A. (106°). This companion galaxy is seen in the [O II] 3727 images given in McCarthy et al. (1995), and spectroscopy with the Hale 5 m telescope confirms that it lies at the same redshift as 3C 184. The radio source is 3 double oriented in P.A. 106° (Laing 1981).

     3C 194 (z = 1.185; Fig. 8).The galaxy is composed of two components separated by 2, as can be seen in the ground-based images given by Djorgovski et al. (1988) and Le Fèvre & Hammer (1988). We detect both components, but with low signal-to-noise ratios. The southern component is more compact and has higher surface brightness than the northern component. The position of this component is with 05 of the radio core (van Breugel & McCarthy 1997), and so it is most likely the correct identification. The two components are oriented roughly 15 from the radio axis.

     3C 208.1 (z = 1.02; Figs. 7 and 8).This N galaxy has a compact nucleus and a secondary component 06 northeast. Spectra of the compact object by Le Fèvre & Hammer (1990) reveal broad Mg II 2800 emission, which leads them to classify this object as a quasar. Our image (Fig. 7) shows that the galaxy identified by Le Fèvre & Hammer as a z = 0.159 Seyfert galaxy is resolved into two galaxies lying 27 east and south of 3C 208.1. Le Fèvre & Hammer suggest that 3C 208.1 is a quasar that is gravitationally amplified by this foreground galaxy (pair) by several tenths of a magnitude. It is possible that the compact companion to the radio source is a gravitationally lensed image. A 5 GHz VLA map by van Breugel shows an extension to the core that is in a similar position angle (35° vs. 21°) but that has twice the separation (12) from the core as that of the optical knot. The knot seen in our HST image is 5 mag fainter than the nucleus, whereas the northeast component in the radio is only 1.7 mag weaker than the core. An alternative explanation is that the secondary component is a synchrotron knot, similar to the features seen in HST images of 3CR quasars by Ridgway & Stockton (1997), although the P.A. of the knot is nearly orthogonal to the main axis of the source. The required spectral index between the 5 GHz and F702W images is then -0.56.

     3C 210 (z = 1.169; Fig. 9).This object is resolved into three or more components. The two brightest components are oriented in P.A. 190°, 30° away from the position angle (163°) of the 19 radio double (Strom et al. 1990). The two components are separated by 064, a possible fainter component lies 04 to the northwest. Deep K images obtained by M. Dickinson (private communication) suggest that this object lies in a cluster. This is a source in which the extended optical structure is more likely to be a result of the cluster environment than a manifestation of the alignment effect.

     3C 220.1 (z = 0.620; Fig. 9).This object is well detected and is extended over nearly 2 in P.A. 210°, 50° from the radio axis.

     3C 220.3 (z = 0.685; Fig. 9).This object is poorly detected in our image, and much of what we detect may be associated with the gravitational arc discovered by M. Dickinson (private communication).

     3C 222 (z = 1.34; Fig. 10).This is a very faint compact object and is not well detected in our image. It appears to be slightly extended in P.A. 90°.

     3C 225A (z = 1.56; Fig. 10).The radio source identification is very faint and is confused with a foreground spiral in ground-based images. We marginally detect the radio galaxy, but the signal-to-noise ratio is too poor for it to be of much use.

     3C 225B (z = 0.582; Fig. 10).We detect a compact object near the midpoint of this 5 double source. A map of the source is given in Giovannini et al. (1988). The position for the source given in Spinrad et al. (1985) is 22 east and 45 south of the true position.

     3C 228 (z = 0.5524; Fig. 11).The galaxy is compact with a high central surface brightness.

     3C 238 (z = 1.405, Fig. 11).This galaxy is not well detected. A compact nucleus is seen as is a faint extension 02 to the southwest. We do not detect the faint extension to the north seen in the Le Fèvre, Hammer, & Jones (1988) image taken with the CFHT.

     3C 239 (z = 1.781; Fig. 11).The galaxy is faint with an extension 02 to the northeast. There is a possible companion to the southwest at , = 12, -09.

     3C 247 (z = 0.7489; Fig. 12).This is a complex object with several objects or components within the central few arcseconds. These lie along the radio axis and are probably associated with a group or cluster centered on 3C 247.

     3C 263.1 (z = 0.824; Fig. 12).The galaxy is compact with a high central surface brightness. There is some faint structure surrounding the nucleus on the scale of several tenths of an arcsecond.

     3C 266 (z = 1.275; Fig. 12).This object is very extended with a spectacular morphology. The emission can be traced over more than 25 and is aligned with the radio source axis. The radio source is a 4 double, and the best VLA maps available to us do not reveal a core. The northern lobe lies just beyond the termination of the visible structure in our HST image. The F702W filter does not contain significant [O II] 3727 emission at this redshift. HST images taken with other filters can be found in Best et al. (1996a).

     3C 267 (z = 1.140; Fig. 13).The identification is nucleated. The companion lying 2 to the southwest seen in the ground-based images (see, e.g., McCarthy et al. 1995) is detected in our image and has a lower surface brightness than the nucleus. Long-slit spectra taken by McCarthy et al. (1996) show a velocity difference between the host and companion of 400 km s^-1. The extended structure in this source is significantly misaligned with the radio axis.

     3C 268.1 (z = 0.9737; Fig. 13).The galaxy is well detected and shows faint extended significant structure within the central 1.

     3C 272 (z = 0.994; Fig. 13).The ID is a faint galaxy with possible extension to the southwest, roughly along the axis (P.A. = 25°) of the large radio source. Alternatively, the galaxy might be bisected by a dust lane oriented normal to the radio axis.

     3C 277.2 (z = 0.766; Fig. 14).This galaxy shows complex structure in the inner 2. Much of the curved and clumpy structure seen here may arise from [O II] 3727 contamination in the F702W image. The low surface brightness continuum and [O II] 3727 emission lying 5 southwest seen in the images given by McCarthy et al. (1995) are not detected in our PC images.

     3C 292 (z = 0.713; Fig. 14).The galaxy has a low central surface brightness and is extended over more than 1 along P.A. 40°.

     3C 293.1 (z = 0.709; Fig. 14).The identification is very faint and is not well detected.

     3C 297 (z = 1.406; Fig. 15).The object has two components: a compact, unresolved component, and a resolved component lying 03 to the southeast in P.A. 125°. The southeast component is likely a foreground field galaxy, and it may amplify the radio source if it is sufficiently massive.

     3C 300.1 (z = 1.159; Fig. 15).This galaxy is only marginally detected.

     3C 305.1 (z = 1.132; Fig. 15).The galaxy is very extended with a complex morphology. Emission can be seen over more than 2 with a curved, roughly S-shaped structure in the inner 1. The orientation, size, and curved morphology of the structure seen in our PC image matches that seen in high-resolution radio maps remarkably well. The radio core lies in the gap between the components at = 77°0846 and = 77°0847.

     3C 322 (z = 1.681; Fig. 16).The galaxy is faint and poorly detected.

     3C 323 (z = 0.679; Fig. 16).The identification is well detected and shows symmetric structure over roughly 1.

     3C 325 (z = 0.86; Fig. 16).This N galaxy is very compact with a high central surface brightness.

     3C 330 (z = 0.550; Fig. 17).The galaxy shows considerable structure, but [O III] 5007 images with the linear ramp filter on HST by McCarthy et al. (1996) show that nearly all of this structure arises from line emission.

     3C 337 (z = 0.635; Fig. 17).The galaxy is well detected with a small extension to the southwest. Detailed optical and radio observations of 3C 337 are given in Pedelty et al. (1989b).

     3C 343.1 (z = 0.750; Fig. 17).The identification has a compact nucleus with a second component extending 02 to the west, along the axis of the small double radio source.

     3C 352 (z = 0.8057; Fig. 18).This object is well detected and shows extended structure over nearly 1 in P.A. 0°, similar to the radio source axis. The radio source is a 10 double.

     3C 356 (z = 1.079; Fig. 18).Ground-based images (see, e.g., Le Fevre et al. 1988; Rigler et al. 1992; McCarthy et al. 1995) of 3C 356 show two components. There is some uncertainty as to which of the two components contains the active nucleus that produces 3C 356, as compact radio components have been detected at both positions (see, e.g., Fernini et al. 1993; Pedelty et al. 1989a; Eales & Rawlings 1990). We detect only the northwest component in our image; we do not see the lower surface brightness component 4 to the southeast. Our image shows structure in the northwest component: there is a high surface brightness conelike structure and a fainter extension 06 to the northwest. We believe that the component detected in our image is the true nucleus since nearly all of the other 3CR galaxies at this redshift are detected in our images. A deeper HST image of this object is given by Best et al. (1996a), who also conclude that this component is the correct identification.

     3C 427.1 (z = 0.572 Fig. 18).This galaxy has a diffuse morphology extended over slightly more than 1 with no coherent structure.

     3C 441 (z = 0.707; Fig. 19).The host galaxy is well detected with a slight extension to the northwest, along the radio axis. The galaxy seen in the northwest lobe, as shown in the continuum and [O II] 3727 images given McCarthy et al. (1995), is well detected in our image as are several other potential cluster members.

     3C 454.1 (z = 1.841; Fig. 19).The identification is marginally detected. There are two components, oriented along the radio axis, as shown by Djorgovski et al. (1988) in their ground-based images. This is a small steep-spectrum double source (Pearson, Perley, & Readhead 1985), and it clearly shows a strong alignment effect in deep ground-based images.

     3C 469.1 (z = 1.336; Fig. 19).The galaxy is well detected and shows a double structure in P.A. 95°, not aligned with the radio axis.

§4. SUMMARY AND ACKNOWLEDGMENTS

     We have presented HST snapshot images of a sample of 51 3CR radio galaxies at large redshifts. These basic data will be used in subsequent papers to examine the apparent evolution in the morphology of powerful radio galaxies and to explore the alignment effect and the unification of radio galaxies and quasars.

ACKNOWLEDGMENTS

     We thank the support staff of the Space Telescope Science Institute for their assistance with the acquisition and processing of the data. G. K. M. acknowledges support from an EU research grant, a NATO research grant, and a Programme Subsidy from the Netherlands Organization for Pure Research (NWO).

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FIGURES

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TABLES

TABLE 2
RADIO AND SPECTROSCOPIC PROPERTIES: RADIO GALAXIES WITH z > 0.5

3CR (1)	z (2)	S(178) a (3)	log P b (4)	a (5)	LAS c (6)	P.A. (radio) d (7)	W([O II]) (8)	Remarks (9)
6.1...	0.840	13.7	35.89	0.80	25.8	26	59
13.0...	1.351	12.0	36.54	0.93	28.0	145	246
22.0...	0.937	12.1	35.96	0.78	24.5	103	111
34.0...	0.6220	11.9	35.64	1.06	46.0	85	215
36.0...	1.301	8.2	36.21	0.85	9.0	20	77
41.0...	0.794	10.6	35.67	0.51	23.1	41
44.0...	0.6600	7.9	35.42	0.83	65.0	11	77
54.0...	0.8274	8.8	35.67	0.82	52.0	25	115
55.0...	0.7348	21.5	35.96	1.04	69.0	94	86
65.0...	1.176	15.2	36.36	0.75	17.6	98	64
107.0...	0.785	10.8	35.75	1.02	20.7
114.0...	0.815	6.5	35.54	0.89	51.5	45	50
124.0...	1.083	10.3	36.08	1.18	1.3	7	373
169.1...	0.633	7.3	35.31	0.90	38.0	137
172.0...	0.5191	15.1	35.42	0.86	103.0	37	122
184.0...	0.994	13.2	36.10	0.86	4.4	106		Very strong [O II]
194.0...	1.185	9.9	36.15	0.79	14.2	151
208.1...	1.02	8.1	35.85	0.65	5.2	103
210.0...	1.169	9.5	36.13	0.78	19.0	167	77
220.1...	0.620	15.8	35.67	0.93	29.7	79
220.3...	0.685	15.7	35.79	0.75	7.1	117
222.0...	1.34	11.3	36.39	1.17
225A...	1.56	7.6	36.40	0.93	2.0	15	121
225B...	0.582	21.3	35.71	0.94	5.0	127
228.0...	0.5524	21.8	35.64	1.00	45.0	9	112
238.0...	1.405	16.6	36.65	0.82	7.6	163
239.0...	1.781	13.2	36.88	1.08	11.1	75	204 e
247.0...	0.7489	10.6	35.65	0.61	13.6	69	113
255.0...	1.355	12.5	36.44	0.87	00.7
263.1...	0.824	18.2	36.03	0.87	5.8	49
266.0...	1.275	11.1	36.38	1.01	4.0	177	522
267.0...	1.140	14.6	36.28	0.93	38.0	79	189
268.1...	0.9737	21.4	36.19	0.59	44.0	83	100
272.0...	0.944	8.0	35.83	0.87	57.0	25
277.2...	0.766	12.0	35.74	1.02	54.0	61	169
292.0...	0.713	10.1	35.56	0.80	132.0	162
293.1...	0.709	9.2	35.66	0.99	52.0	45		Very weak lines
297.0...	1.4061	10.3	36.29	0.98	4.0	167
305.1...	1.132	4.6	35.77	0.48	7.9	11	259
323.0...	0.679	8.4	35.49	0.81	32.0	9	61
325.0...	0.860	15.6	36.01	0.70	16.2	121		Weak [O II]
330.0...	0.550	27.8	35.73	0.71	62.0	62	143
337.0...	0.635	11.8	35.53	0.63	43.0	102	28
343.1...	0.750	11.5	35.72	0.32	0.2	97
352.0...	0.8057	11.3	35.81	0.88	10.2	164	158
356.0...	1.079	11.3	36.12	1.02	72.0	162	116
427.1...	0.572	26.6	35.81	0.97	23.1	140
441.0...	0.707	12.6	35.64	0.83	33.0	149	57
454.1...	1.847	9.8	36.83	0.82	1.7	167	521 e
469.1...	1.336	11.1	36.39	0.96	74.0	171	200

TABLE 3
POSITIONS AND MAGNITUDES

3CR	(1950)	(1950)	z	Magnitude (2)	Magnitude (4)	Remarks
6.1...	00 13 34.90	79 00 10.2	0.840	22.6	22.5
13.0...	00 34 14.79	39 24 12.1	1.351	23.3	23.1
22.0...	00 48 04.77	50 55 44.8	0.937	22.0	21.7
34.0...	01 07 32.61	31 31 22.6	0.6220	23.4	22.5
36.0...	01 15 03.47	45 20 36.7	1.301	23.6	23.4
41.0...	01 23 54.82	32 57 38.3	0.794	21.9	21.4
44.0...	01 28 43.94	06 08 37.6	0.6600	21.9	21.4
54.0...	01 52 25.91	43 31 20.9	0.8274	23.3	23.0
55.0...	01 54 19.15	28 37 02.4	0.7348	23.3	23.0
	01 54 19.09	28 37 02.6		23.9	23.6	NW object
65.0...	02 20 37.03	39 47 20.3	1.176	23.8	23.0
107.0...	04 09 49.88	-01 07 10.6	0.785	23.3	22.9
114.0...	04 17 29.05	17 46 48.6	0.815	23.9	23.1
124.0...	04 39 23.94	01 15 20.8	1.083	23.6	22.5
169.1...	06 47 35.16	45 13 06.5	0.633	21.8	21.3
	06 47 35.25	45 13 03.6	0.633	22.3	22.1	NW object
172.0...	06 59 04.17	25 18 15.9	0.5191	21.9	21.4	Nucleus
	06 59 03.99	25 18 12.9		21.5	21.5	Stellar object
	06 59 03.72	25 18 11.0		23.0	22.3	SW object
	06 59 03.96	25 18 06.4		23.2	22.8	SW object
184.0...	07 33 59.14	70 30 04.1	0.994	22.9	22.3
194.0...	08 06 37.98	42 36 57.3	1.185	24.8	24.4	SW object
	08 06 37.99	42 36 58.9		24.2	23.7	NE object
208.1...	08 51 53.31	14 17 19.8	1.02	20.0	19.9	Nucleus
	08 51 53.33	14 17 20.3				NE object
210.0...	08 55 10.92	28 02 35.9	1.169	23.5	22.7	Magnitude for both components
	08 55 10.93	28 02 36.6
220.1...	09 26 32.05	79 19 44.2	0.620	21.9	21.3
220.3...	09 31 12.58	83 28 54.8	0.685	23.8	23.3	Poorly detected
222.0...	09 33 55.20	04 35 38.8	1.34	24.7	24.7
225A...	09 39 25.20	14 05 36.5	1.56			Marginal detection
225B...	09 39 32.45	13 59 33.0	0.582	23.1	22.5:
228.0...	09 47 27.84	14 34 05.1	0.5524	22.0	21.6
238.0...	10 08 23.15	06 39 29.6	1.405	23.9	23.6
239.0...	10 08 39.04	46 43 08.4	1.781	23.6	23.2
247.0...	10 56 08.43	43 17 29.9	0.7489	22.4	21.8
255.0...	11 16 52.25	-02 46 25.7	1.355			Marginal detection
263.1...	11 40 49.26	22 23 34.6	0.824	21.9	21.7
266.0...	11 43 04.33	50 02 48.8	1.275	23.6	22.6
267.0...	11 47 22.11	13 04 00.0	1.140	24.2	23.8
	11 47 22.00	13 03 58.7		24.4	23.8	SW object
268.1...	11 57 49.33	73 17 28.5	0.9737	23.5	23.3
272.0...	12 22 00.87	42 23 12.9	0.944	23.7	23.4
277.2...	12 51 03.97	15 58 46.7	0.766	22.5	21.9
292.0...	13 49 13.40	64 44 22.3	0.713	23.3	22.8
293.1...	13 52 16.21	16 29 30.5	0.709	24.7		Poorly detected
297.0...	14 14 47.85	-03 46 59.3	1.4061	22.9	22.6	Nucleus
	14 14 47.84	-03 46 59.1		22.8	22.5	SE galaxy
300.1...	14 25 56.59	-01 10 48.7	1.159	23.7
305.1...	14 47 49.27	77 08 47.1	1.132	23.1	22.4
323.0...	15 40 48.44	60 25 01.5	0.679	22.9	22.3
325.0...	15 49 14.02	62 50 20.6	0.86	20.5	20.4
330.0...	16 09 14.20	66 04 19.7	0.550	21.1	20.7
337.0...	16 27 18.94	44 25 37.8	0.635	22.3	21.9
343.1...	16 37 55.31	62 40 34.5	0.750	22.4	21.8
352.0...	17 09 18.01	46 05 06.0	0.8057	23.1	22.5
356.0...	17 23 06.69	51 00 17.8	1.079	22.8	22.5
427.1...	21 04 44.98	76 21 06.8	0.572	23.1	22.7
441.0...	22 03 50.16	29 14 35.3	0.707	22.5	22.0	Nucleus
	22 03 49.46	29 14 42.9	0.707	23.3	22.6	NW lobe
454.1...	22 48 58.81	71 13 23.4	1.82			Poorly detected
469.1...	23 52 58.53	79 38 37.7	1.336	23.8	23.6