Large‐Scale Structures in the Early Sloan Digital Sky Survey: Comparison of the North and South Galactic Strips

Abstract We test the hypothesis that environments play a key role in enabling the growth of enormous radio structures spanning more than 700 kpc, an extreme population of radio galaxies called giant radio galaxies (GRGs). To achieve this, we explore (1) the relationships between the occurrence of GRGs and the surface number density of surrounding galaxies, including satellite galaxies and galaxies from neighboring halos, as well as (2) the GRG locations towards large-scale structures. The analysis is done by making use of a homogeneous sample of 110 GRGs detected from the LOFAR Two-metre Sky Survey in combination with photometric galaxies from the DESI Legacy Imaging Surveys and a large-scale filament catalog from the Sloan Digital Sky Survey. Our results show that the properties of galaxies around GRGs are similar with that around the two control samples, consisting of galaxies with optical colors and luminosity matched to the properties of the GRG host galaxies. Additionally, the properties of surrounding galaxies depend on neither their relative positions to the radio jet/lobe structures nor the sizes of GRGs. We also find that the locations of GRGs and the control samples with respect to the nearby large-scale structures are consistent with each other. These results demonstrate that there is no correlation between the GRG properties and their environments traced by stars, indicating that external galaxy environments are not the primary cause of the large sizes of the radio structures. Finally, regarding radio feedback, we show that the fraction of blue satellites does not correlate with the GRG properties, suggesting that the current epoch of radio jets have minimal influence on the nature of their surrounding galaxies.

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Identification of Extremely Large Scale Structures in SDSS-III

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316010036 ◽

2014 ◽

Vol 11 (S308) ◽

pp. 299-300

Author(s):

Shishir Sankhyayan ◽

J. Bagchi ◽

P. Sarkar ◽

V. Sahni ◽

J. Jacob

Keyword(s):

Large Scale ◽

Sloan Digital Sky Survey ◽

Limited Sample ◽

Large Scale Structures ◽

Large Structures ◽

Density Peaks ◽

Redshift Surveys ◽

Sky Survey ◽

Scale Structures ◽

The Universe

AbstractWe have initiated the search and detailed study of large scale structures present in the universe using galaxy redshift surveys. In this process, we take the volume-limited sample of galaxies from Sloan Digital Sky Survey III and find very large structures even beyond the redshift of 0.2. One of the structures is even greater than 600 Mpc which raises a question on the homogeneity scale of the universe. The shapes of voids-structures (adjacent to each other) seem to be correlated, which supports the physical existence of the observed structures. The other observational supports include galaxy clusters' and QSO distribution's correlation with the density peaks of the volume limited sample of galaxies.

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The orientation of galaxy pairs with filamentary structures: dependence on morphology

Astronomy and Astrophysics ◽

10.1051/0004-6361/201832910 ◽

2018 ◽

Vol 619 ◽

pp. A24 ◽

Cited By ~ 6

Author(s):

Valeria Mesa ◽

Fernanda Duplancic ◽

Sol Alonso ◽

Maria Rosa Muñoz Jofré ◽

Georgina Coldwell ◽

...

Keyword(s):

Large Scale ◽

Elliptical Galaxies ◽

Sloan Digital Sky Survey ◽

Morphological Classification ◽

Large Scale Structures ◽

Significant Alignment ◽

Sky Survey ◽

The Galaxy ◽

High Fraction ◽

Scale Structures

Aims. With the aim of performing an analysis of the orientations of galaxy pair systems with respect to the underlying large-scale structure, we study the alignment between the axis connecting the pair galaxies and the host cosmic filament where the pair resides. In addition, we analyze the dependence of the amplitude of the alignment on the morphology of pair members as well as filament properties. Methods. We build a galaxy pair catalog requiring rp < 100 h−1 kpc and ΔV < 500 km s−1 within redshift z < 0.1 from the Sloan Digital Sky Survey (SDSS). We divided the galaxy pair catalog taking into account the morphological classification by defining three pair categories composed by elliptical–elliptical (E–E), elliptical–spiral (E–S) and spiral–spiral (S–S) galaxies. We use a previously defined catalog of filaments obtained from SDSS and we select pairs located closer than 1 h−1 Mpc to the filament spine, which are considered as members of filaments. For these pairs, we calculate the relative angle between the axis connecting each galaxy, and the direction defined by the spine of the parent filament. Results. We find a statistically significant alignment signal between the pair axes and the spine of the host filaments consistent with a relative excess of ∼15% aligned pairs. We obtain that pairs composed by elliptical galaxies exhibit a stronger alignment, showing a higher alignment signal for pairs closer than 200 h−1 kpc to the filament spine. In addition, we find that the aligned pairs are associated with luminous host filaments populated with a high fraction of elliptical galaxies. The findings of this work show that large-scale structures play a fundamental role in driving galactic anisotropic accretion as induced by galaxy pairs exhibiting a preferred alignment along the filament direction.

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X-Ray and Radio Emissions of AWM and MKW Clusters

Proceedings of the Wisconsin Space Conference ◽

10.17307/wsc.v0i0.41 ◽

2012 ◽

Author(s):

Michael Ramuta

Keyword(s):

Large Scale ◽

Life Cycles ◽

Sloan Digital Sky Survey ◽

X Ray ◽

Large Scale Structures ◽

Sky Survey ◽

Scale Structures ◽

Using Data ◽

And Behavior ◽

The Universe

A grasp of the life-cycles of large-scale structures is critical to understanding the Universe. This can be accomplished through the study of poor clusters-- that is, younger clusters that are likely evolving to another state. The selected clusters are significant in that they are poor but also possess a type-cD galaxy. This brighter central galaxy suggests that these clusters may be dynamically evolved and are potential candidates for fossil groups. In order to more fully understand the structure and behavior of poor galaxy clusters, 12 clusters were selected and analyzed. Using data from the Sloan Digital Sky Survey, Chandra X-Ray Archive, and the VLA FIRST Survey, we present x-ray profiles and radio observations of these 12 galaxy clusters.Â

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An Obscured Galaxy Redshift Survey with FLAIR

Publications of the Astronomical Society of Australia ◽

10.1071/as97126a ◽

1997 ◽

Vol 14 (1) ◽

pp. 126-126 ◽

Cited By ~ 1

Author(s):

K. Wakamatsu ◽

M. Malkan ◽

Q. A. Parker ◽

H. Karoji

Keyword(s):

Large Scale ◽

Wall Structure ◽

Galactic Centre ◽

Large Scale Structures ◽

Sky Survey ◽

Centre Region ◽

Redshift Survey ◽

Galaxy Redshift ◽

Scale Structures ◽

Zone Of Avoidance

A problem for studies of large scale structures in nearby space (cz < 10,000 km s-1) is the presence of the Zone of Avoidance which is so large and wide on the sky that potentially important clusters and voids remain undetected. A prime example was the Ophiuchus cluster discovered by Wakamatsu and Malkan (1981) as a heavily obscured cD cluster close to the Galactic centre region (l = 0·5°, b = +9·5°). It is the second brightest X-ray cluster after Perseus. A hidden galaxy survey was performed by visually searching ESO/SERC Sky Survey (R and J) copy films of the region centred at l = 355°, b = +10° finding more than 4000 galaxies in six fields. Several irregular clusters adjacent to Ophiuchus were found forming a supercluster which may be connected to the Hercules supercluster by a wall structure parallel to the local supergalactic plane (Wakamatsu et al. 1994). In front of this supercluster, an 'Ophiuchus Void' is suggested (cz = 4,500 km s-1). The Ophiuchus supercluster at cz = 8,500 km s-1 is similar to the Hercules supercluster (cz = 11,000 km s-1), and extends north toward the latter supercluster.

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A New 1.4 GHz Radio Continuum Map of the Sky South of Declination +25°

Publications of the Astronomical Society of Australia ◽

10.1017/pasa.2013.36 ◽

2014 ◽

Vol 31 ◽

Cited By ~ 40

Author(s):

Mark R. Calabretta ◽

Lister Staveley-Smith ◽

David G. Barnes

Keyword(s):

Large Scale ◽

Thermal Emission ◽

High Sensitivity ◽

Radio Continuum ◽

Archival Data ◽

Large Scale Structures ◽

Low Level ◽

Sky Survey ◽

Scale Structures ◽

Zone Of Avoidance

AbstractArchival data from the HI Parkes All-Sky Survey (HIPASS) and the HI Zone of Avoidance (HIZOA) survey have been carefully reprocessed into a new 1.4 GHz continuum map of the sky south of δ = +25°. The wide sky coverage, high sensitivity of 40 mK (limited by confusion), resolution of 14.4 arcmin (compared to 51 arcmin for the Haslam et al. 408 MHz and 35 arcmin for the Reich et al. 1.4 GHz surveys), and low level of artefacts make this map ideal for numerous studies, including: merging into interferometer maps to complete large-scale structures; decomposition of thermal and non-thermal emission components from Galactic and extragalactic sources; and comparison of emission regions with other frequencies. The new map is available for download.

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Large Scale Structure in the Local Universe — The 2MASS Galaxy Catalog

Publications of the Astronomical Society of Australia ◽

10.1071/as04050 ◽

2004 ◽

Vol 21 (4) ◽

pp. 396-403 ◽

Cited By ~ 64

Author(s):

Thomas Jarrett

Keyword(s):

Large Scale ◽

Near Infrared ◽

Local Universe ◽

Extended Source ◽

Large Scale Structures ◽

Photometric Redshift ◽

Sky Survey ◽

Nearby Galaxies ◽

Scale Structures ◽

Zone Of Avoidance

AbstractUsing twin ground-based telescopes, the Two-Micron All Sky Survey (2MASS) scanned both equatorial hemispheres, detecting more than 500 million stars and resolving more than 1.5 million galaxies in the near-infrared (1–2.2 μm) bands. The Extended Source Catalog (XSC) embodies both photometric and astrometric whole sky uniformity, revealing large scale structures in the local Universe and extending our view into the Milky Way's dust-obscured ‘Zone of Avoidance’. The XSC represents a uniquely unbiased sample of nearby galaxies, particularly sensitive to the underlying, dominant, stellar mass component of galaxies. The basic properties of the XSC, including photometric sensitivity, source counts, and spatial distribution, are presented here. Finally, we employ a photometric redshift technique to add depth to the spatial maps, reconstructing the cosmic web of superclusters spanning the sky.

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The Universe Behind the Southern Milky Way

Symposium - International Astronomical Union ◽

10.1017/s0074180900196640 ◽

2005 ◽

Vol 216 ◽

pp. 203-210 ◽

Cited By ~ 2

Author(s):

Renée C. Kraan-Korteweg ◽

Lister Staveley-Smith ◽

Jennifer Donley ◽

Bärbel Koribalski ◽

Patricia A. Henning

Keyword(s):

Surface Brightness ◽

Large Scale ◽

High Surface ◽

Star Forming ◽

Large Scale Structures ◽

The North ◽

Low Surface Brightness ◽

Scale Structures ◽

Zone Of Avoidance ◽

The Universe

A first analysis of a deep blind HI survey covering the southern Zone of Avoidance plus an extension towards the north (196† ≤ ℓ ≤ 52†) obtained with the Multibeam receiver at the 64-m Parkes telescope reveals slightly over a thousand galaxies within the latitude completeness limit of |b| ≤ 5†. The characteristics and the uncovered large-scale structures of this survey are described, in particular the prominence of the Norma Supercluster, the possible cluster around PKS 1343–601 (both in the Great Attractor region), as well as the Local Void and the clustering in the Puppis region. In this blind HI survey HIZOA J0836–43 was discovered, one of the most massive spiral galaxies known to date (MHI = 7.3 × 1010 M⊙, MT = 1.1 × 1012 M⊙; H0 = 75 km/s/Mpc). Although of similar mass to Malin 1-like objects, this galaxy does not share their typical low-surface brightness properties, but seems an exceptionally massive but normal, high surface brightness, star-forming galaxy.

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Some comments about observations and image processing of comet 29P/Schwassmann-Wachmann 1

International Astronomical Union Colloquium ◽

10.1017/s0252921100031493 ◽

1999 ◽

Vol 173 ◽

pp. 243-248

Author(s):

D. Kubáček ◽

A. Galád ◽

A. Pravda

Keyword(s):

Image Processing ◽

Large Scale ◽

Harvard College ◽

Oak Ridge ◽

Large Scale Structures ◽

Short Period Comet ◽

Short Period ◽

Scale Structures ◽

Harvard College Observatory ◽

Period Comet

AbstractUnusual short-period comet 29P/Schwassmann-Wachmann 1 inspired many observers to explain its unpredictable outbursts. In this paper large scale structures and features from the inner part of the coma in time periods around outbursts are studied. CCD images were taken at Whipple Observatory, Mt. Hopkins, in 1989 and at Astronomical Observatory, Modra, from 1995 to 1998. Photographic plates of the comet were taken at Harvard College Observatory, Oak Ridge, from 1974 to 1982. The latter were digitized at first to apply the same techniques of image processing for optimizing the visibility of features in the coma during outbursts. Outbursts and coma structures show various shapes.

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