Evidence for large-scale structure on scales about $\sim 300 \,h^{-1}$ Mpc

Plionis, M.; Valdarnini, R.

doi:10.1093/mnras/249.1.46

Cited by 44 publications

(61 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The Shapley supercluster (hereafter SSC) because of its peculiar richness and location, lying in the direction of the dipole anisotropy of the Cosmic Microwave Background (CMB), was investigated as responsible of at least a fraction of the Local Group acceleration (Scaramella et al 1989;Raychaudhury 1989;Plionis & Valdarnini 1991;Quintana et al 1995;Kocevski et al 2004;Feindt et al 2013, and references therein). To assess the role of this structure in the acceleration of the Local Group a robust estimate of its mass is required.…”

Section: The Target: Shapley Superclustermentioning

confidence: 99%

Shapley Supercluster Survey: Galaxy evolution from filaments to cluster cores

Merluzzi

Busarello

Haines

et al. 2014

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We present an overview of a multi-wavelength survey of the Shapley supercluster (SSC; z∼0.05) covering a contiguous area of 260 h (SC 1327-312, SC 1329 showing evidence of cluster-cluster interactions. Optical (ugri) and near-infrared (K) imaging acquired with VST and VISTA allow us to study the galaxy population down to m ⋆ +6 at the supercluster redshift. A dedicated spectroscopic survey with AAOmega on the Anglo-Australian Telescope provides a magnitude-limited sample of supercluster members with 80% completeness at ∼m ⋆ +3. We derive the galaxy density across the whole area, demonstrating that all structures within this area are embedded in a single network of clusters, groups and filaments. The stellar mass density in the core of the SSC is always higher than 9×10 9 M ⊙ Mpc −3 , which is ∼40× the cosmic stellar mass density for galaxies in the local Universe. We find a new filamentary structure (∼7 Mpc long in projection) connecting the SSC core to the cluster A 3559, as well as previously unidentified density peaks. We perform a weak-lensing analysis of the central 1 deg 2 field of the survey obtaining for the central cluster A 3558 a mass of M 500 = 7.63 +3.88 −3.40 × 10 14 M ⊙ , in agreement with X-ray based estimates.

show abstract

Section: The Target: Shapley Superclustermentioning

confidence: 99%

Shapley Supercluster Survey: Galaxy evolution from filaments to cluster cores

Merluzzi

Busarello

Haines

et al. 2014

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

show abstract

“…2 With cluster surveys avoiding the Galactic plane, the distribution of large-scale structures that are the accelerators of such flows in this region has remained largely unknown. A variety of techniques have been used to reconstruct the ZOA, ranging from uniform filling (Strauss & Davis 1988;Lahav 1987) to a spherical harmonics approach that extends structures above and below the plane into the ZOA (Plionis & Valdarnini 1991;cf. Brunozzi et al 1995), but the value of these reconstruction techniques is limited if the MW does indeed obscure dynamically significant structures, as has been suggested.…”

Section: The Zone Of Avoidancementioning

confidence: 99%

A Systematic X‐Ray Search for Clusters of Galaxies behind the Milky Way. II. The Second CIZA Subsample

Kocevski¹,

Ebeling²,

Mullis³

et al. 2007

ApJ

101

103

View full text Add to dashboard Cite

We present the latest results of the Clusters in the Zone of Avoidance (CIZA) survey, which is mapping large-scale structures behind the Milky Way by performing the first systematic search for galaxy clusters at low Galactic latitudes. The survey's approach, which uses X-ray emission to locate cluster candidates, minimizes the problems faced by optically selected cluster surveys, which have traditionally avoided this region of the sky due to the severe extinction present along the Galactic plane. We here present the second flux-limited CIZA cluster catalog, containing 57 X-ray-selected galaxy clusters, of which 88% are new discoveries. We use this sample to examine the degree to which known large-scale structures extend into the zone of avoidance and highlight newly discovered structures that have previously gone unnoticed. We note that the CIZA survey has thus far found fewer rich clusters in the Great Attractor region than would be expected given the region's proposed mass. Instead, we find a significant increase in the number of clusters behind the Great Attractor, with the most notable being an association of clusters near the Shapley supercluster. We propose that these clusters trace an extension of the large-scale filament network in which the Shapley concentration is embedded. We also highlight an association of clusters near the Galactic anticenter, which form the first supercluster found to be completely hidden by the Milky Way. Our preliminary findings of a less massive Great Attractor and the detection of significant structures behind the complex support studies that suggest the motion of nearby galaxies is due, in part, to a large-scale bulk flow, which is induced by overdensities beyond the Hydra-Centaurus region.

show abstract

“…[94], [93]). Later studies, indicated that another very massive and more distant (∼ 140 h −1 Mpc) attractor could play a significant role in shaping the local dynamics ( [151], [152], [122]). It seems that the coherence scale of the velocity field could extend to even larger distances than what originally thought (cf.…”

Section: Thermal Beginning Of the Universementioning

confidence: 99%

“…Now, galaxy clusters, being the largest gravitationally-collapsed structures in the universe and luminous enough to be detected to very large distances, have also been used to probe the local acceleration field. Most studies are based on the optically selected abell/aco clusters [1] and they provide strong evidence that the LG dipole has significant contributions from depths up to ∼ 160h −1 Mpc (see Fig.12 and [152], [122], [26]). However, due to the the volume incompleteness of richness class R=0 clusters (cf.…”

Section: Local Group Dipolementioning

confidence: 99%

“…Furthermore the galaxy and cluster distributions produce Local Group acceleration profiles that are directly proportional to each other (see Fig.13), while the dipole in equal volume shells, seems to be roughly aligned with the CMB dipole direction out to very large depths (cf. [122], [11]). This implies that there is a coherent anisotropy in the mass distribution over a region with a diameter of ∼ 300 h −1 Mpc, which then sets a lower limit to the scales over which the Cosmological Principle applies.…”

Section: Local Group Dipolementioning

confidence: 99%

See 1 more Smart Citation

The Quest for the Cosmological Parameters

Plionis

2002

Cosmological Crossroads

Self Cite

View full text Add to dashboard Cite

Abstract. The following review is based on lectures given in the 1 st Samos Cosmology summer school. It presents an attempt to discuss various issues of current interest in Observational Cosmology, the selection of which as well as the emphasis given, reflects my own preference and biases. After presenting some Cosmological basics, for which I was aided by excellent text-books, I emphasize on attempts to determine some of the important cosmological parameters; the Hubble constant, the curvature and total mass content of the Universe. The outcome of these very recent studies is that the concordance model, that fits the majority of observations, is that with04 and spectral index of primordial fluctuations, the inflationary value n ≃ 1. I apologise before hand for the many important works that I have omitted and for the possible misunderstanding of those presented. Background-PrerequisitesThe main task of Observational Cosmology is to identify which of the idealized models, that theoretical Cosmologists construct, relates to the Universe we live in. One may think that since we cannot perform experiments and study, in a laboratory sense, the Universe as a whole, this is a futile task. Nature however has been graceful, and through the detailed and exhaustive analysis of the detected electromagnetic radiation emitted from the different photon-generating processes, we can do wonders! Among the many important tasks of Observational Cosmology is the determination of the total mass-energy density of the Universe, the rate of its expansion, its age, the amount of ordinary and exotic matter that it contains, as well as to quantify in a objective and bias free manner the large-scale distribution of matter, as traced by galaxies, clusters of galaxies and AGN's for example.However, these tasks are not easy to fulfil. Subjective (instrumentation, available funds, technological limitations etc) as well as objective (observational biases, limitations due to our position in space-time, etc) difficulties exist. Furthermore, we do not know whether the Universe accessible to our observations is representative of the whole Universe. A positive answer to this question is essential in order to meaningfully compare observations with theory. Under the assumption that the Universe is homogeneous and isotropic (in a statistical sense), well separated regions can be viewed as independent realizations of the same formation process. Therefore many of such regions constitute an ensemble and thus we can employ statistical techniques in our study.

show abstract

Evidence for large-scale structure on scales about $\sim 300 \,h^{-1}$ Mpc

Cited by 44 publications

References 0 publications

Shapley Supercluster Survey: Galaxy evolution from filaments to cluster cores

Shapley Supercluster Survey: Galaxy evolution from filaments to cluster cores

A Systematic X‐Ray Search for Clusters of Galaxies behind the Milky Way. II. The Second CIZA Subsample

The Quest for the Cosmological Parameters

Contact Info

Product

Resources

About