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The largest galaxies, and in particular central galaxies in clusters, offer unique insight into understanding the mechanism for the growth of nuclear black holes. We present Hubble Space Telescope kinematics for NGC1399, the central galaxy in Fornax. We find the best-fit model contains a black hole of 5.1 +-0.7 x 10^8 Msun (at a distance of 21.1 Mpc), a factor of over 2 below the correlation of black hole mass and velocity dispersion. We also find a dramatic signature for central tangential anisotropy. The velocity profiles on adjacent sides 0.5" away from the nucleus show strong bimodality, and the central spectrum shows a large drop in the dispersion. Both of these observations point to an orbital distribution that is tangentially biased. The best-fit orbital model suggests a ratio of the tangential to radial internal velocity dispersions of three. This ratio is the largest seen in any galaxy to date and will provide an important measure for the mode by which the central black hole has grown., Comment: 9 pages, accepted for publication in the Astrophysical Journal

We present observations of 77 early-type galaxies imaged with the PC1 CCD of the Hubble Space Telescope (HST) WFPC2. "Nuker-law" parametric fits to the surface brightness profiles are used to classify the central structure into "core" or "power-law" forms. Core galaxies are typically rounder than power-law galaxies. Nearly all power-law galaxies with central ellipticities ε ≥ 0.3 have stellar disks, implying that disks are present in power-law galaxies with ε < 0.3 but are not visible because of unfavorable geometry. A few low-luminosity flattened core galaxies also have disks; these may be transition forms from power-law galaxies to more luminous core galaxies, which lack disks. Several core galaxies have strong isophote twists interior to their break radii, although power-law galaxies have interior twists of similar physical significance when the photometric perturbations implied by the twists are evaluated. Central color gradients are typically consistent with the envelope gradients; core galaxies have somewhat weaker color gradients than power-law galaxies. Nuclei are found in 29% of the core galaxies and 60% of the power-law galaxies. Nuclei are typically bluer than the surrounding galaxy. While some nuclei are associated with active galactic nuclei (AGNs), just as many are not; conversely, not all galaxies known to have a low-level AGN exhibit detectable nuclei in the broadband filters. NGC 4073 and 4382 are found to have central minima in their intrinsic starlight distributions; NGC 4382 resembles the double nucleus of M31. In general, the peak brightness location is coincident with the photocenter of the core to a typical physical scale of < 1 pc. Five galaxies, however, have centers significantly displaced from their surrounding cores; these may be unresolved asymmetric double nuclei. Finally, as noted by previous authors, central dust is visible in about half of the galaxies. The presence and strength of dust correlates with nuclear emission; thus, dust may outline gas that is falling into the central black hole. The prevalence of dust and its morphology suggest that dust clouds form, settle to the center, and disappear repeatedly on ∼ 108 yr timescales. We discuss the hypothesis that cores are created by the decay of a massive black hole binary formed in a merger. Apart from their brightness profiles, there are no strong differences between core galaxies and power-law galaxies that demand this scenario; however, the rounder shapes of core, their lack of disks, and their reduced color gradients may be consistent with it. © 2005. The American Astronomical Society. All rights reserved.

Observations of nearby galaxies reveal a strong correlation between the mass of the central dark object M and the velocity dispersion sigma of the host galaxy, of the form log(M/M_sun) = a + b*log(sigma/sigma_0); however, published estimates of the slope b span a wide range (3.75 to 5.3). Merritt & Ferrarese have argued that low slopes (, 37 pages, 9 figures

We put active galactic nuclei (AGNs) with low-mass black holes on the fundamental plane of black hole accretion---the plane that relates X-ray emission, radio emission, and mass of an accreting black hole---to test whether or not the relation is universal for both stellar-mass and supermassive black holes. We use new Chandra X-ray and Very Large Array radio observations of a sample of black holes with masses less than $10^{6.3}\ M_{\scriptscriptstyle \odot}$, which have the best leverage for determining whether supermassive black holes and stellar-mass black holes belong on the same plane. Our results suggest that the two different classes of black holes both belong on the same relation. These results allow us to conclude that the fundamental plane is suitable for use in estimating supermassive black hole masses smaller than $\sim 10^7\ M_{\scriptscriptstyle \odot}$, in testing for intermediate-mass black holes, and in estimating masses at high accretion rates., ApJL accepted. 5 pages

Black hole (BH) masses that have been measured by reverberation mapping in active galaxies fall significantly below the correlation between bulge luminosity and BH mass determined from spatially resolved kinematics of nearby normal galaxies. This discrepancy has created concern that one or both techniques suffer from systematic errors. We show that BH masses from reverberation mapping are consistent with the recently discovered relationship between BH mass and galaxy velocity dispersion. Therefore the bulge luminosities are the probable source of the disagreement, not problems with either method of mass measurement. This result underscores the utility of the BH mass -- velocity dispersion relationship. Reverberation mapping can now be applied with increased confidence to galaxies whose active nuclei are too bright or whose distances are too large for BH searches based on spatially resolved kinematics., Comment: 4 pages, 1 figure, ApJ Letters accepted, minor revisions

We describe a correlation between the mass M_BH of a galaxy's central black hole and the luminosity-weighted line-of-sight velocity dispersion sigma_e within the half-light radius. The result is based on a sample of 26 galaxies, including 13 galaxies with new determinations of black hole masses from Hubble Space Telescope measurements of stellar kinematics. The best-fit correlation is M_BH = 1.2 (+-0.2) x 10^8 M_sun (sigma_e/200 km/s)^(3.75 (+-0.3))over almost three orders of magnitude in M_BH; the scatter in M_BH at fixed sigma_e is only 0.30 dex and most of this is due to observational errors. The M_BH-sigma_e relation is of interest not only for its strong predictive power but also because it implies that central black hole mass is constrained by and closely related to properties of the host galaxy's bulge., Comment: 4 pages, accepted ApJ Letters, figure added and minor corrections

We present new ROSAT PSPC X-ray pointed observations of nine Abell clusters that contain wide- angle tailed (WAT) radio galaxies. The sample of WAT clusters was selected from a VLA radio survey of the Abell catalog at 20 cm and the ROSAT All-Sky Survey (RASS). We found that up to eight (89%) clusters show some evidence of X-ray substructure. These clusters also have clear evidence of isophotal twisting, ellipticity variation, and isophote centroid variation as a function of distance from the central X-ray peak. Moreover, none of these WAT clusters have signi—cant cluster-wide cooling —ows in spite of the presence of dominant elliptical (radio) galaxies. We performed temperature —ts to the X-ray emission by applying a Raymond-Smith —t to the spectra and a ii broadband ˇˇ temperature technique. One strik- ing correlation with the radio sources was discovered: there is a strong relationship between the orienta- tion of the WAT tails and the direction of X-ray elongations within the core of the clusters. We believe that this is consistent with WAT clusters undergoing mergers with groups or subclusters of galaxies. We compared our results with numerical hydro/N-body simulations of merging galaxy clusters to test this hypothesis. We found that the X-ray synthetic images generated by the simulations reproduce all the major morphological properties that we found in our sample. Furthermore, the simulations also show that the bulk —ow of gas within the ICM present during the merger could be responsible for the corre- lation between the X-ray elongations and the direction of the bending of the radio tails. Subject headings: galaxies: clusters: generalgalaxies: interactionsgalaxies: structure ¨ intergalactic mediumradio continuum: galaxiesX-rays: galaxies

We present HST STIS observations of the galaxy NGC 4382 (M85) and axisymmetric models of the galaxy to determine mass-to-light ration (M/L, V-band) and central black hole mass (M_BH). We find M/L = 3.74 +/- 0.1 (solar units) and M_BH = 1.3 (+5.2, -1.2) \times 10^7 M_sun at an assumed distance of 17.9 Mpc, consistent with no black hole. The upper limit, M_BH < 9.6 \times 10^7 M_sun (2{\sigma}) or M_BH < 1.4 \times 10^8 M_sun (3{\sigma}) is consistent with the current M-{\sigma} relation, which predicts M_BH = 8.8 \times 10^7 M_sun at {\sigma}_e = 182 km/s, but low for the current M-L relation, which predicts M_BH = 7.8 \times 10^8 M_sun at L_V = 8.9 \times 10^10 L_sun,V. HST images show the nucleus to be double, suggesting the presence of a nuclear eccentric stellar disk, in analogy to the Tremaine disk in M31. This conclusion is supported by the HST velocity dispersion profile. Despite the presence of this non-axisymmetric feature and evidence of a recent merger, we conclude that the reliability of our black hole mass determination is not hindered. The inferred low black hole mass may explain the lack of nuclear activity., Comment: 10 pages, 8 figures, accepted by ApJ

We report five new measurements of central black hole masses based on STIS and WFPC2 observations with the Hubble Space Telescope and on axisymmetric, three-integral, Schwarzschild orbit-library kinematic models. We selected a sample of galaxies within a narrow range in velocity dispersion that cover a range of galaxy parameters (including Hubble type and core/power-law surface density profile) where we expected to be able to resolve the galaxy's sphere of influence based on the predicted value of the black hole mass from the M-sigma relation. We find masses in units of 10^8 solar masses for the following galaxies: NGC 3585, M_BH = 3.4 (+1.5, -0.6); NGC 3607, M_BH = 1.2 (+0.4, -0.4); NGC 4026, M_BH = 2.1 (+0.7, -0.4); and NGC 5576, M_BH = 1.8 (+0.3, -0.4), all significantly excluding M_BH = 0. For NGC 3945, M_BH = 0.09 (+0.17, -0.21), which is significantly below predictions from M-sigma and M-L relations and consistent with M_BH = 0, though the presence of a double bar in this galaxy may present problems for our axisymmetric code., 15 pages, 21 figures, 13 tables. Accepted by ApJ

We derive improved versions of the relations between supermassive black hole mass (M_BH) and host-galaxy bulge velocity dispersion (sigma) and luminosity (L) (the M-sigma and M-L relations), based on 49 M_BH measurements and 19 upper limits. Particular attention is paid to recovery of the intrinsic scatter (epsilon_0) in both relations. We find log(M_BH / M_sun) = alpha + beta * log(sigma / 200 km/s) with (alpha, beta, epsilon_0) = (8.12 +/- 0.08, 4.24 +/- 0.41, 0.44 +/- 0.06) for all galaxies and (alpha, beta, epsilon_0) = (8.23 +/- 0.08, 3.96 +/- 0.42, 0.31 +/- 0.06) for ellipticals. The results for ellipticals are consistent with previous studies, but the intrinsic scatter recovered for spirals is significantly larger. The scatter inferred reinforces the need for its consideration when calculating local black hole mass function based on the M-sigma relation, and further implies that there may be substantial selection bias in studies of the evolution of the M-sigma relation. We estimate the M-L relationship as log(M_BH / M_sun) = alpha + beta * log(L_V / 10^11 L_sun,V) of (alpha, beta, epsilon_0) = (8.95 +/- 0.11, 1.11 +/- 0.18, 0.38 +/- 0.09); using only early-type galaxies. These results appear to be insensitive to a wide range of assumptions about the measurement errors and the distribution of intrinsic scatter. We show that culling the sample according to the resolution of the black hole's sphere of influence biases the relations to larger mean masses, larger slopes, and incorrect intrinsic residuals., Comment: 27 pages, 18 figures, 7 tables, ApJ accepted

We determine the mass of the black hole at the center of the spiral galaxy NGC 4258 by constructing axisymmetric dynamical models of the galaxy. These models are constrained by high spatial resolution imaging and long-slit spectroscopy of the nuclear region obtained with the {\em Hubble Space Telescope}, complemented by ground-based observations extending to larger radii. Our best mass estimate is $\MBH = (3.3 \pm 0.2) \times 10^7 \MSun $ for a distance of 7.28 Mpc (statistical errors only). This is within 15% of $ (3.82\pm 0.01) \times 10^7 \MSun$, the mass determined from the kinematics of water masers (rescaled to the same distance) assuming they are in Keplerian rotation in a warped disk. The construction of accurate dynamical models of NGC 4258 is somewhat compromised by an unresolved active nucleus and color gradients, the latter caused by variations in the stellar population and/or obscuring dust. These problems are not present in the $\sim 30$ other black hole mass determinations from stellar dynamics that have been published by us and other groups; thus, the relatively close agreement between the stellar dynamical mass and the maser mass in NGC 4258 enhances our confidence in the black hole masses determined in other galaxies from stellar dynamics using similar methods and data of comparable quality., 58 pages, submitted to ApJ. Some figures excluded due to size. The entire paper is at http://www.noao.edu/noao/staff/lauer/nuker_papers.html

Black hole masses predicted from the Mbh-sigma relationship conflict with those predicted from the Mbh-L relationship for the most luminous galaxies, such as brightest cluster galaxies (BCGs). This is because stellar velocity dispersion, sigma, increases only weakly with L for BCGs and other giant ellipticals. The Mbh-L relationship predicts that the most luminous BCGs may have Mbh approaching 10^{10}M_sol, while the M-sigma relationship always predicts Mbh3X10^9M_sol may be nearly an order of magnitude richer than that inferred from the Mbh-sigma relationship. The volume density of QSOs at earlier epochs may favor the predictions from the Mbh-L relationship., 62 pages, 18 figures, submitted to the Astrophysical Journal; revised after initial review

We present stellar kinematics for a sample of 10 early-type galaxies observed using the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope and the Modular Spectrograph on the MDM Observatory 2.4 m telescope. These observations are a part of an ongoing program to understand the coevolution of supermassive black holes and their host galaxies. Our spectral ranges include either the calcium triplet absorption lines at 8498, 8542, and 8662 Åor the Mg b absorption at 5175 Å. The lines are used to derive line-of-sight velocity distributions (LOSVDs) of the stars using a maximum penalized likelihood method. We use Gauss-Hermite polynomials to parameterize the LOSVDs and find predominantly negative h4 values (boxy distributions) in the central regions of our galaxies. One galaxy, NGC 4697, has significantly positive central h4 (high tail weight). The majority of galaxies have a central velocity dispersion excess in the STIS kinematics over ground-based velocity dispersions. The galaxies with the strongest rotational support, as quantified with vmax/σSTIS have the smallest dispersion excess at STIS resolution. The best-fitting, general, axisymmetric dynamical models (described in a companion paper) require black holes in all cases, with masses ranging from 106.5 to 10 9.3 M⊙. We replot these updated masses on the M BH-σ relation and show that the fit to only these 10 galaxies has a slope consistent with the fits to larger samples. The greatest outlier is NGC 2778, a dwarf elliptical with relatively poorly constrained black hole mass. The two best candidates for pseudobulges, NGC 3384 and NGC 7457, do not deviate significantly from the established relation between MBH and σ. Neither do the three galaxies that show the most evidence of a recent merger, NGC 3608, NGC 4473, and NGC 4697.

We used HST WFPC2 images to identify six early-type galaxies with surface- brightness profiles that decrease inward over a limited range of radii near their centers. The implied luminosity density profiles of these galaxies have local minima interior to their core break radii. NGC 3706 harbors a high surface brightness ring of starlight with radius ~20 pc. Its central structure may be related to that in the double-nucleus galaxies M31 and NGC 4486B. NGC 4406 and NGC 6876 have nearly flat cores that on close inspection are centrally depressed. Colors for both galaxies imply that this is not due to dust absorption. The surface brightness distributions of both galaxies are consistent with stellar tori that are more diffuse than the sharply defined system in NGC 3706. The remaining three galaxies are the brightest cluster galaxies in A260, A347, and A3574. Color information is not available for these objects, but they strongly resemble NGC 4406 and NGC 6876 in their cores. The thin ring in NGC 3706 may have formed dissipatively. The five other galaxies resemble the endpoints of some simulations of the merging of two gas-free stellar systems, each harboring a massive nuclear black hole. In one version of this scenario, diffuse stellar tori are produced when stars initially bound to one black hole are tidally stripped away by the second black hole. Alternatively, some inward-decreasing surface-brightness profiles may reflect the ejection of stars from a core during the hardening of the binary black hole created during the merger., 35 pages, 17 postscript figures, submitted to the Astronomical Journal

We present axisymmetric, orbit superposition models for 12 galaxies using data taken with the Hubble Space Telescope (HST) and ground-based observatories. In each galaxy, we detect a central black hole (BH) and measure its mass to accuracies ranging from 10% to 70%. We demonstrate that in most cases the BH detection requires both the HST and ground-based data. Using the ground-based data alone does provide an unbiased measure of the BH mass (provided they are fit with fully general models), but at a greatly reduced significance. The most significant correlation with host galaxy properties is the relation between the BH mass and the velocity dispersion of the host galaxy; we find no other equally strong correlation, and no second parameter that improves the quality of the mass-dispersion relation. We are also able to measure the stellar orbital properties from these general models. The most massive galaxies are strongly biased to tangential orbits near the BH, consistent with binary BH models, while lower-mass galaxies have a range of anisotropies, consistent with an adiabatic growth of the BH., 25 pages, accepted for publication in The Astrophysical Journal

Galaxies that contain bulges appear to contain central black holes whose masses correlate with the velocity dispersion of the bulge. We show that no corresponding relationship applies in the pure disk galaxy M33. Three-integral dynamical models fit Hubble Space Telescope WFPC2 photometry and STIS spectroscopy best if the central black hole mass is zero. The upper limit is 1500 M_sun. This is significantly below the mass expected from the velocity dispersion of the nucleus and far below any mass predicted from the disk kinematics. Our results suggest that supermassive black holes are associated only with galaxy bulges and not with their disks., Comment: 8 pages, AJ accepted, November issue

`Wakes' of X-ray emission have now been detected trailing behind a few (at least seven) elliptical galaxies in clusters. To quantify how widespread this phenomenon is, and what its nature might be, we have obtained a deep (70 ksec) X-ray image of the poor cluster Abell 160 using the ROSAT HRI. Combining the X-ray data with optical positions of confirmed cluster members, and applying a statistic designed to search for wake-like excesses, we confirm that this phenomenon is observed in galaxies in this cluster. The probability that the detections arise from chance is less than 0.0038. Further, the wakes are not randomly distributed in direction, but are preferentially oriented pointing away from the cluster centre. This arrangement can be explained by a simple model in which wakes arise from the stripping of their host galaxies' interstellar media due to ram pressure against the intracluster medium through which they travel., Comment: 7 pages, 7 figures, accepted for publication in MNRAS

We present new redshifts and positions for 635 galaxies in nine rich clusters containing Wide-Angle Tailed (WAT) radio galaxies. Combined with existing data, we now have a sample of 18 WAT-containing clusters with more than 10 redshifts. This sample contains a substantial portion of the WAT clusters in the VLA 20 cm survey of Abell clusters, including 75% of WAT clusters in the complete survey (z0.09. It is a representative sample which should not contain biases other than selection by radio morphology. We graphically present the new data using histograms and sky maps. A semi-automated procedure is used to search for emission lines in the spectra in order to add and verify galaxy redshifts. We find that the average apparent fraction of emission line galaxies is about 9% in both the clusters and the field. We investigate the magnitude completeness of our redshift surveys with CCD data for a test case, Abell 690. This case indicates that our galaxy target lists are deeper than the detection limit of a typical MX exposure, and they are 82% complete down to R=19.0. The importance of the uniformity of the placement of fibers on targets is posited, and we evaluate this in our datasets. We find some cases of non-uniformities which may influence dynamical analyses. A second paper will use this database to look for correlations between the WAT radio morphology and the cluster's dynamical state., 15 pages, 5 figures, 7 tables. To appear in the Astronomical Journal

We present WFPC2 images of the core of the cooling flow cD galaxy in Abell 1795. An irregular, asymmetric dust lane extends 7 \h75 kpc in projection to the north-northwest. The dust shares the morphology observed in the H$\alpha$ and excess UV emission. We see both diffuse and knotty blue emission around the dust lane, especially at the ends. The dust and emission features lie on the edge of the radio lobes, suggesting star formation induced by the radio source or the deflection of the radio jets off of pre-existing dust and gas. We measure an apparent R$_V$ significantly less than 3.1, implying that the extinction law is not Galactic in the dust lane, or the presence of line emission which is proportional to the extinction. The dust mass is at least 2$\times10^{5} h_{75}^{-2}$ M\solar\ and is more likely to be 6.5$\times10^{5} h_{75}^{-2}$ M\solar., Comment: 14 pages, LaTeX, Figure 4 included, Postscript Figs. 1-3 available at ftp://astro.nmsu.edu/pub/JASON/A1795/, accepted for publication in ApJ Letters

New ROSAT X‐ray imaging of clusters with extended radio galaxies is described. We present evidence for a strong correlation between the positions of radio galaxies and clumped X‐ray emission within galaxy clusters. This correlation is interpreted as the result of mergers between clusters. We argue that radio galaxies are good probes of the dynamical state of clusters. In particular, wide‐angle tailed radio sources may be the best tool that presently exists for sampling large‐scale gas motions in clusters which have undergone mergers. We also present hybrid Hydro/N‐body simulations of cluster mergers which show that (1) cluster gas cores are heated via shocks, (2) cooling cores are likely destroyed during mergers, (3) bulk gas motions of ≊1000 km/s persist for about 5 Gyr following the mergers, and (4) the intracluster gas may not be in hydrostatic equilibrium for clusters with significant X‐ray substructure.

We present results of a study of the dynamics of the rich cluster Abell 2634. Spectroscopic observations were obtained using the MX spectrometer on the Steward Observatory 2.3 m telescope. The spectrometer utilizes 2‘ diameter silica fibers which are independently positioned in the telescope focal plane by micoprocessor controlled mechanical arms. We have obtained ∼100 radial velocities of galaxies in this cluster with an accuracy of ∼100 km/s. This cluster is of particular interest since its cD galaxy (NGC 7720) has been identified with the wide‐angle tail radio source 3C 465. The tail has a northwest extent of 130 kpc. The observations of Scott, Robertson and Tarenghi (1977) indicate that NGC 7720 has a peculiar velocity of ∼330 km/s with respect to the mean cluster velocity. We do not measure a significant peculiar motion for the cD galaxy. We also do not find evidence of substructure in this cluster or deviations from normality of the galaxy velocity distribution.

New x-ray, optical, and redshift data are presented for the cluster of galaxies associated with the giant, 1 Mpc diameter, wide-angle tailed (WAT) radio galaxy 1919+479. The ROSAT Position-Sensitive Proportional Counter (PSPC) pointed observation shows an x-ray peak on the WAT and elongated diffuse emission tracing the galaxy distribution. In addition, an asymmetric extension of emission exists between the tails of the WAT. The fitting of a Raymond-Smith thermal model to the x-ray spectra suggests an approximately = 2 keV temperature intracluster medium (ICM). The cooling time and irregular morphology rule out a cluster-wide cooling flow. The x-ray luminosity and temperature are consistent with the velocity dispersion, 480 km/s, estimated from 31 galaxy velocities. However, this velocity distribution is significantly non-Gaussian, which along with the x-ray morphology, suggests incomplete virialization in the cluster. Substructure analysis does not reveal significant clumping in the velocities/positions; but, the spatial distribution of galaxies is very elongated. Also, the cD galaxy producing the WAT does not have a significant radial peculiar velocity with respect to the cluster centroid. These characteristics are consistent with a merger scenario in which a subcluster has crossed the cluster core in the plane of the sky and has dispersed. We compare this cluster with the post-merger cluster Abell 2634 (Pinkney et al., 1993), containing the prototype WAT, and with a recent N-Body/Hydro simulation of merging clusters. The similarities indicate that the cluster 1919+479 may be the poor extreme of a class of clusters in which the bulk motion in the ICM, caused by a subcluster merger, in shaping the central WAT.

We have made a comparison of the X-ray and radio morphologies for a sample of 41 rich cluster fields using Einstein Observatory Imaging Proportional Counter (IPC) and Very Large Array (VLA) 20 cm images. Surprisingly, we find that 75% of the radio galaxies have a statistically significant X-ray peak or subclump within 5 min of the radio galaxy position. The X-ray luminosity and the generally extended nature of the X-ray subclumps suggest that these subclumps are overdense regions emitting free-free radiation, although there is also evidence for Active Galactic Nuclei (AGN) X-ray emission coming from some of the more compact, high surface brightness X-ray peaks. Some interesting correlations with radio morphology were also discovered. For clusters which contain wide-angle-tailed radio sources associated with centrally dominant galaxies, there are significant elongations or clumps in the central X-ray emission which are unusual for this type of cluster. We suggest that cluster radio galaxies are pointers to particular clusters or regions within clusters that have recently undergone mergers between cluster subsystems.

We have collected a large sample of galaxy velocities for the nearby, rich cluster of galaxies Abell 2634, which contains the prototypical wide-angle tailed (WAT) radio source 3C 465 associated with the central cD galaxy. Robust indicators of location (i.e., velocity mean) and scale (velocity dispersion) and their confidence intervals are used to determine the velocity structure of the cluster. We find a cD peculiar radial velocity of −219±98 km s −1 . The Dressler-Shectman δ-test reveals significant deviations in the local dynamics on the east side of the cluster, probably due to subcluster contamination. The velocity distribution is Gaussian except for a few outliers, where the velocity outliers tend to be spatial outliers