The Tolman Surface Brightness Test for the Reality of the Expansion. III. HST Profile and Surface Brightness Data for Early-Type Galaxies in Three High-Redshift Clusters

Photometric data for 34 early-type galaxies in the three high-redshift clusters Cl 1324+3011 (z = 0.76), Cl 1604+4304 (z = 0.90), and Cl 1604+4321 (z = 0.92), observed with the Hubble Space Telescope (HST) and with the Keck 10-meter telescopes by Oke, Postman & Lubin, are analyzed to obtain the photometric parameters of mean surface brightness, magnitudes for the growth curves, and angular radii at various Petrosian eta radii. The angular radii at eta = 1.3 mag for the program galaxies are all larger than 0.24". All of the galaxies are well resolved at this angular size using HST whose point-spread function is 0.05", half width at half maximum. The data for each of the program galaxies are listed at eta = 1.0, 1.3, 1.5, 1.7, and 2.0 mag. They are corrected by color equations and K terms for the effects of redshift to the rest-frame Cape/Cousins I for Cl 1324+3011 and Cl 1604+4304 and R for Cl 1604+4321. The K corrections are calculated from synthetic spectral energy distributions derived from evolving stellar population models of Bruzual & Charlot which have been fitted to the observed broad-band (BVRI) AB magnitudes of each program galaxy. The listed photometric data are independent of all cosmological parameters. They are the source data for the Tolman surface brightness test made in Paper IV.Comment: 17 pages, 7 figures; accepted for publication in the Astronomical Journa

A Statistical Treatment of the Gamma-Ray Burst "No Host Galaxy" Problem: II. Energies of Standard Candle Bursts

With the discovery that the afterglows after some bursts are coincident with faint galaxies, the search for host galaxies is no longer a test of whether bursts are cosmological, but rather a test of particular cosmological models. The methodology we developed to investigate the original "no host galaxy" problem is equally valid for testing different cosmological models, and is applicable to the galaxies coincident with optical transients. We apply this methodology to a family of models where we vary the total energy of standard candle bursts. We find that total isotropic energies of E<2e52~erg are ruled out while log(E)~53 erg is favored.Comment: To appear in Ap.J., 514, 15 pages + 7 figures, AASTeX 4.0. Revisions are: additional author, updated data, and minor textual change

The Dipole Anisotropy of the First All-Sky X-ray Cluster Sample

We combine the recently published CIZA galaxy cluster catalogue with the XBACs cluster sample to produce the first all-sky catalogue of X-ray clusters in order to examine the origins of the Local Group's peculiar velocity without the use of reconstruction methods to fill the traditional Zone of Avoidance. The advantages of this approach are (i) X-ray emitting clusters tend to trace the deepest potential wells and therefore have the greatest effect on the dynamics of the Local Group and (ii) our all-sky sample provides data for nearly a quarter of the sky that is largely incomplete in optical cluster catalogues. We find that the direction of the Local Group's peculiar velocity is well aligned with the CMB as early as the Great Attractor region 40 h^-1 Mpc away, but that the amplitude of its dipole motion is largely set between 140 and 160 h^-1 Mpc. Unlike previous studies using galaxy samples, we find that without Virgo included, roughly ~70% of our dipole signal comes from mass concentrations at large distances (>60 h^-1 Mpc) and does not flatten, indicating isotropy in the cluster distribution, until at least 160 h^-1 Mpc. We also present a detailed discussion of our dipole profile, linking observed features to the structures and superclusters that produce them. We find that most of the dipole signal can be attributed to the Shapley supercluster centered at about 150 h^-1 Mpc and a handful of very massive individual clusters, some of which are newly discovered and lie well in the Zone of Avoidance.Comment: 15 Pages, 9 Figures. Accepted by Ap

Optical and X-ray clusters as tracers of the supercluster-void network. I Superclusters of Abell and X-ray clusters

We study the distribution of X-ray selected clusters of galaxies with respect to superclusters determined by Abell clusters of galaxies and show that the distribution of X-ray clusters follows the supercluster-void network determined by Abell clusters. We find that in this network X-ray clusters are more strongly clustered than other clusters. Poor, non-Abell X-ray clusters follow the supercluster-void network as well: these clusters are embedded in superclusters determined by rich clusters and populate filaments between them. We present a new catalog of superclusters of Abell clusters out to a redshift of z_{lim}=0.13, a catalog of X-ray clusters located in superclusters determined by Abell clusters, and a list of additional superclusters of X-ray clusters.Comment: LaTex (sty files added), 16 pages, 3 ps figures, submitted to Astronomical Journal. Animations of the 3D distribution of superclusters of Abell and X-ray clusters at http://www.aai.ee/~maret/SCLVnet.ht

The Tolman Surface Brightness Test for the Reality of the Expansion. I. Calibration of the Necessary Local Parameters

The extensive CCD photometry by Postman & Lauer (1995, ApJ, 440, 28) in the Cape/Cousins R photometric band for first ranked cluster elliptical and S0 galaxies in 118 low redshift clusters is analyzed for the correlations between average surface brightness, linear radius, and absolute magnitude. The purpose is to calibrate the correlations between these three parameters in the limit of zero redshift. These local correlations provide the comparisons to be made in Paper IV with the sample of early-type galaxies at high redshift in search of the Tolman surface brightness signal of (1 + z)^4 if the expansion is real. Surface brightness averages are calculated at various metric radii in each galaxy in the sample. The definition of such radii by Petrosian (1976, ApJ, 209, L1) uses ratios of observed surface photometric data. The observed surface brightnesses are listed for 118 first ranked cluster galaxies at Petrosian eta radii of 1.0, 1.3, 1.5, 1.7, 2.0, and 2.5 mag. The three local diagnostic correlation diagrams are defined and discussed. We review the Tolman test and show that, although recipes from the standard cosmological model that already have the Tolman signal incorporated are required to calculate linear radii and absolute magnitudes from the observed data, the test is nevertheless free from the hermeneutical circularity dilemma occasionally claimed in the literature. The reasons are the observed mean surface brightness (1) is independent of any assumptions of cosmological model, (2) does not depend on the existence of a Tolman signal because it is calculated directly from the data using only angular radii and apparent magnitudes, and (3) can be used to search for the Tolman signal because it carries the bulk of that signal.Comment: 34 pages, 4 figures; accepted for publication in Astronomical Journa

The Rest-Frame Extreme Ultraviolet Spectral Properties of QSOs

We use a sample of 332 Hubble Space Telescope spectra of 184 QSOs with z > 0.33 to study the typical ultraviolet spectral properties of QSOs, with emphasis on the ionizing continuum. Our sample is nearly twice as large as that of Zheng et al. (1997) and provides much better spectral coverage in the extreme ultraviolet (EUV). The overall composite continuum can be described by a power law with index alpha_EUV = -1.76 +/- 0.12 (f_nu ~ nu^alpha) between 500 and 1200 Angstroms. The corresponding results for subsamples of radio-quiet and radio-loud QSOs are alpha_EUV = -1.57 +/- 0.17 and alpha_EUV = -1.96 +/- 0.12, respectively. We also derive alpha_EUV for as many individual objects in our sample as possible, totaling 39 radio-quiet and 40 radio-loud QSOs. The typical individually measured values of alpha_EUV are in good agreement with the composites. We find no evidence for evolution of alpha_EUV with redshift for either radio-loud or radio-quiet QSOs. However, we do find marginal evidence for a trend towards harder EUV spectra with increasing luminosity for radio-loud objects. An extrapolation of our radio-quiet QSO spectrum is consistent with existing X-ray data, suggesting that the ionizing continuum may be represented by a single power law. The resulting spectrum is roughly in agreement with models of the intergalactic medium photoionized by the integrated radiation from QSOs.Comment: 14 pages using emulateapj, 15 figures, accepted for publication in Ap

The Tolman Surface Brightness Test for the Reality of the Expansion. IV. A Measurement of the Tolman Signal and the Luminosity Evolution of Early-Type Galaxies

We review a sample of the early literature in which the reality of the expansion is discussed, explain Hubble's reticence to accept the expansion as real, and contrast the Tolman surface brightness test with three other modern tests. We search for the Tolman surface brightness depression with redshift using the Hubble Space Telescope (HST) data from Paper III for 34 early-type galaxies from the three clusters Cl 1324+3011 (z=0.76), Cl 1604+4304 (z=0.90), and Cl 1604+4321 (z=0.92). Depressions of the surface brightness relative to the zero-redshift fiducial lines in the mean surface brightness, log linear radius diagrams of Paper I are found for all three clusters. Expressed as the exponent, n, in 2.5 log (1 + z)^n mag, the value of n for all three clusters is n = 2.59 +/- 0.17 in the R band and 3.37 +/- 0.13 in the I band for a q_o = 1/2 model. The sensitivity of the result to the assumed value of q_o is shown to be less than 23% between q_o = 0 and +1. For a true Tolman signal with n = 4, the luminosity evolution in the look-back time, expressed as the exponent in 2.5 log (1+z)^(4-n) mag, must then be between 1.72 to 1.19 in the R band and 0.94 to 0.45 in the I band. We show that this is precisely the range expected from the evolutionary models of Bruzual & Charlot. We conclude that the Tolman surface brightness test is consistent with the reality of the expansion. We have also used the high-redshift HST data to test the ``tired light'' speculation for a non-expansion model for the redshift. The HST data rule out the ``tired light'' model at a significance level of better than 10 sigma.Comment: 36 pages, 6 figures; accepted for publication in the Astronomical Journa

The Effects of Inhomogeneities on Evaluating the mass parameter Ωm\Omega_m and the cosmological constant Λ\Lambda

Analytic expressions for distance-redshift relations which have been corrected for the effects of inhomogeneities in the Friedmann-Lema\^itre-Robertson-Walker (FLRW) mass density are given in terms of Heun functions and are used to illustrate the significance of inhomogeneities on a determination of the mass parameter $\Omega_m$ and the cosmological constant $\Lambda$. The values of these parameters inferred from a given set of observations depend on the fractional amount of matter in inhomogeneities and can significantly differ from those obtained by using the standard magnitude-redshift ($m$-$z$) result for pure dust FLRW models. As an example a determination of $\Omega_m$ made by applying the homogeneous distance-redshift relation to SN 1997ap at $z=0.83$ could be as much as 50% lower than its true value.Comment: 39 pages including 8 figures and captions. To appear in ApJ 507 (Nov. 1998

A Serendipitous Galaxy Cluster Survey with XMM: Expected Catalogue Properties and Scientific Applications

This paper describes a serendipitous galaxy cluster survey that we plan to conduct with the XMM X-ray satellite. We have modeled the expected properties of such a survey for three different cosmological models, using an extended Press-Schechter (Press & Schechter 1974) formalism, combined with a detailed characterization of the expected capabilities of the EPIC camera on board XMM. We estimate that, over the ten year design lifetime of XMM, the EPIC camera will image a total of ~800 square degrees in fields suitable for the serendipitous detection of clusters of galaxies. For the presently-favored low-density model with a cosmological constant, our simulations predict that this survey area would yield a catalogue of more than 8000 clusters, ranging from poor to very rich systems, with around 750 detections above z=1. A low-density open Universe yields similar numbers, though with a different redshift distribution, while a critical-density Universe gives considerably fewer clusters. This dependence of catalogue properties on cosmology means that the proposed survey will place strong constraints on the values of Omega-Matter and Omega-Lambda. The survey would also facilitate a variety of follow-up projects, including the quantification of evolution in the cluster X-ray luminosity-temperature relation, the study of high-redshift galaxies via gravitational lensing, follow-up observations of the Sunyaev-Zel'dovich effect and foreground analyses of cosmic microwave background maps.Comment: Accepted to ApJ. Minor changes, e.g. presentation of temperature errors as a figure (rather than as a table). Latex (20 pages, 6 figures, uses emulateapj.sty

Large-scale periodicity in the distribution of QSO absorption-line systems

The spatial-temporal distribution of absorption-line systems (ALSs) observed in QSO spectra within the cosmological redshift interval z = 0.0--4.3 is investigated on the base of our updated catalog of absorption systems. We consider so called metallic systems including basically lines of heavy elements. The sample of the data displays regular variations (with amplitudes ~ 15 -- 20%) in the z-distribution of ALSs as well as in the eta-distribution, where eta is a dimensionless line-of-sight comoving distance, relatively to smoother dependences. The eta-distribution reveals the periodicity with period Delta eta = 0.036 +/- 0.002, which corresponds to a spatial characteristic scale (108 +/- 6) h(-1) Mpc or (alternatively) a temporal interval (350 +/- 20) h(-1) Myr for the LambdaCDM cosmological model. We discuss a possibility of a spatial interpretation of the results treating the pattern obtained as a trace of an order imprinted on the galaxy clustering in the early Universe.Comment: AASTeX, 13 pages, with 9 figures, Accepted for publication in Astrophysics & Space Scienc