Mass-to-Light Ratios of Early- and Late-Type Galaxies

AbstractWe present the first measurement of the growth rate of structure at z=0.8. It has been obtained from the redshift-space distortions observed in the galaxy clustering pattern in the VIMOS Public Redshift survey (VIPERS) first data release. VIPERS is a large galaxy redshift survey probing the large-scale structure at 0.5 < z < 1.2 with an unprecedented accuracy. This measurement represents a new reference in the distant Universe, which has been poorly explored until now. We obtain σ8 = 0.47 ± 0.08 at z = 0.8 that is consistent with the predictions of standard cosmological models based on Einstein gravity. This measurement alone is however not accurate enough to allow the detection of possible deviations from standard gravity.

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Supernovae and their host galaxies – VII. The diversity of Type Ia supernova progenitors

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2940 ◽

2020 ◽

Vol 499 (1) ◽

pp. 1424-1440

Author(s):

A A Hakobyan ◽

L V Barkhudaryan ◽

A G Karapetyan ◽

M H Gevorgyan ◽

G A Mamon ◽

...

Keyword(s):

Light Curve ◽

Early Type ◽

Young Population ◽

Late Type ◽

Host Galaxies ◽

Decline Rate ◽

Type Ia ◽

First Time ◽

Global Parameters ◽

Host Relations

ABSTRACT We present an analysis of the light curve (LC) decline rates (Δm15) of 407 normal and peculiar supernovae (SNe) Ia and global parameters of their host galaxies. As previously known, there is a significant correlation between the Δm15 of normal SNe Ia and global ages (morphologies, colours, and masses) of their hosts. On average, those normal SNe Ia that are in galaxies from the Red Sequence (early-type, massive, old hosts) have faster declining LCs in comparison with those from the Blue Cloud (late-type, less massive, younger hosts) of the colour–mass diagram. The observed correlations between the Δm15 of normal SNe Ia and hosts’ parameters appear to be due to the superposition of at least two distinct populations of faster and slower declining normal SNe Ia from older and younger stellar components. We show, for the first time, that the Δm15 of 91bg- and 91T-like SNe is independent of host morphology and colour. The distribution of hosts on the colour–mass diagram confirms the known tendency for 91bg-like SNe to occur in globally red/old galaxies, while 91T-like events prefer blue/younger hosts. On average, the youngest global ages of 02cx-like SNe hosts and their positions in the colour–mass diagram hint that these events likely originate from young population, but they differ from 91T-like events in the LC decline rate. Finally, we discuss the possible explosion channels and present our favoured SN Ia models that have the potential to explain the observed SN–host relations.

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Large-Scale Structure from 2dFGRS

Symposium - International Astronomical Union ◽

10.1017/s0074180900196524 ◽

2005 ◽

Vol 216 ◽

pp. 77-94 ◽

Cited By ~ 1

Author(s):

J. A. Peacock

Keyword(s):

Large Scale ◽

Essential Role ◽

Broad Band ◽

Relative Bias ◽

Joint Analysis ◽

Early Type ◽

Full Data ◽

Distortion Parameter ◽

Redshift Survey ◽

Galaxy Redshift

The 2dF Galaxy Redshift Survey is now complete, and the full data are public. 2dFGRS was the first survey to observe more than 100,000 redshifts, making possible precise measurements of many aspects of galaxy clustering, which can be studied as a function of galaxy spectral type, and also of broad-band colour. Early-type galaxies are more strongly clustered than late types, with a relative bias of b = 1.25 ± 0.09 on large scales. For both types, luminosity dependence of clustering is detected at high significance, and is well described by a relative bias of b/b* = 0.85 + 0.15(L/L*). This is consistent with the observation that L* in rich clusters is brighter than the global value by 0.28 ± 0.08 mag. Redshift-space distortions from large-scale infall velocities measure the distortion parameter β = Ω0.6m/b = 0.49 ± 0.09. The power spectrum is measured to ≲ 10% accuracy for k > 0.02 h Mpc--1, and is well fitted by a CDM model with Ωmh = 0.18 ± 0.02 and a baryon fraction of 0.17 ± 0.06. The 2dFGRS plays an essential role in breaking model degeneracies inherent in CMB data; a joint analysis with WMAP results requires Ωm = 0.25 ± 15% and h = 0.73 ± 5%, assuming scalar fluctuations.

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Morphological Distribution of Galaxies in Some Nearby Clusters

Open Astronomy ◽

10.1515/astro-2019-0007 ◽

2019 ◽

Vol 28 (1) ◽

pp. 98-109

Author(s):

Mariwan A. Rasheed ◽

Khalid K. Mohammad

Keyword(s):

Survey Data ◽

Concentration Index ◽

Color Space ◽

Sloan Digital Sky Survey ◽

Early Type ◽

Late Type ◽

Sky Survey ◽

Data Release ◽

The Galaxy ◽

Morphological Distribution

Abstract We study the morphological distribution of galaxies in some nearby clusters, using the Sloan Digital Sky Survey – Data Release 9 (SDSS-DR9). The segregation between early-type galaxies and late-type ones is investigated in g – r / u – g color space, using the color cut u – r = 2.22. The results are compared with those obtained using a color cut that changes with magnitude. They are found to be consistent, particularly for late-type galaxies. The results obtained by the fixed color-cut criterion are also found to be consistent with those obtained by the inverse concentration index parameter, especially for early-type galaxies. Comparable results are obtained for the stacked sample, whose morphologies, given by the fixed color-cut criterion are compared with the visual morphologies provided by the Galaxy Zoo project. A good degree of consistency is seen, which becomes more evident for late-type galaxies.

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Color and magnitude dependence of galaxy clustering

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316010012 ◽

2014 ◽

Vol 11 (S308) ◽

pp. 293-294

Author(s):

Volker Müller

Keyword(s):

Quantitative Study ◽

Galaxy Formation ◽

Absolute Magnitude ◽

Analytical Models ◽

Galaxy Clustering ◽

Data Release ◽

Redshift Survey ◽

Galaxy Redshift

AbstractA quantitative study of the clustering properties of galaxies in the cosmic web as a function of absolute magnitude and colour is presented using the SDSS Data Release 7 galaxy redshift survey. We compare our results with mock galaxy samples obtained with four different semi-analytical models of galaxy formation imposed on the merger trees of the Millenium simulation.

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The DEEP3 Galaxy Redshift Survey: the impact of environment on the size evolution of massive early-type galaxies at intermediate redshift★†

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2011.19938.x ◽

2011 ◽

Vol 419 (4) ◽

pp. 3018-3027 ◽

Cited By ~ 117

Author(s):

Michael C. Cooper ◽

Roger L. Griffith ◽

Jeffrey A. Newman ◽

Alison L. Coil ◽

Marc Davis ◽

...

Keyword(s):

Early Type ◽

Size Evolution ◽

Redshift Survey ◽

Galaxy Redshift ◽

The Impact ◽

Intermediate Redshift

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Anisotropic infall in the outskirts of OmegaWINGS galaxy clusters

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa545 ◽

2020 ◽

Vol 493 (4) ◽

pp. 4950-4959

Author(s):

Juan Manuel Salerno ◽

Héctor J Martínez ◽

Hernán Muriel ◽

Valeria Coenda ◽

Benedetta Vulcani ◽

...

Keyword(s):

Phase Space ◽

Survey Data ◽

Galaxy Clusters ◽

Galaxy Groups ◽

Data Release ◽

Long Time ◽

Redshift Survey ◽

Galaxy Redshift ◽

First Time ◽

Field Galaxy

ABSTRACT We study the effects of the environment on galaxy quenching in the outskirts of clusters at 0.04 < z < 0.08. We use a subsample of 14 WINGS and OmegaWINGS clusters that are linked to other groups/clusters by filaments and study separately galaxies located in two regions in the outskirts of these clusters according to whether they are located towards the filaments’ directions or not. We also use samples of galaxies in clusters and field as a comparison. Filamentary structures linking galaxy groups/clusters were identified over the Six Degree Field Galaxy Redshift Survey Data Release 3. We find a fraction of passive galaxies in the outskirts of clusters intermediate between that of the clusters and the field’s. We find evidence of a more effective quenching in the direction of the filaments. We also analyse the abundance of post-starburst (PS) galaxies in the outskirts of clusters focusing our study on two extreme sets of galaxies according to their phase-space position: backsplash and true infallers. We find that up to $\sim 70{{\ \rm per\ cent}}$ of PS galaxies in the direction of filaments are likely backsplash, while this number drops to $\sim 40{{\ \rm per\ cent}}$ in the isotropic infall region. The presence of this small fraction of galaxies in filaments that are falling into clusters for the first time and have been recently quenched, supports a scenario in which a significant number of filament galaxies have been quenched long time ago.

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Locations of Satellite Galaxies in the Two-Degree Field Galaxy Redshift Survey

ISRN Astronomy and Astrophysics ◽

10.5402/2011/958973 ◽

2011 ◽

Vol 2011 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Ingólfur Ágústsson ◽

Tereasa G. Brainerd

Keyword(s):

Star Formation ◽

Selection Criteria ◽

Photometric Data ◽

Star Forming ◽

Confidence Levels ◽

Isotropic Distribution ◽

Redshift Survey ◽

Galaxy Redshift ◽

Satellite Galaxies ◽

Field Galaxy

We compute the locations of satellite galaxies in the Two-Degree Field Galaxy Redshift Survey using two sets of selection criteria and three sources of photometric data. Using the SuperCOSMOS photometry, we find that the satellites are located preferentially near the major axes of their hosts, and the anisotropy is detected at a highly significant level (confidence levels of 99.6% to 99.9%). The locations of satellites that have high velocities relative to their hosts are statistically indistinguishable from the locations of satellites that have low velocities relative to their hosts. Additionally, satellites with passive star formation are distributed anisotropically about their hosts (99% confidence level), while the locations of star-forming satellites are consistent with an isotropic distribution. These two distributions are, however, statistically indistinguishable. Therefore it is not correct to interpret this as evidence that the locations of the star-forming satellites are intrinsically different from those of the passive satellites.

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