The metal absorption systems of the QSO 0103-260 and the galaxy redshift distribution in the FORS Deep Field

ABSTRACT We revisit our mapping of the ‘Local Hole’, a large underdensity in the local galaxy redshift distribution that extends out to redshift z ≈ 0.05 and a potential source of outflows that may perturb the global expansion rate and thus help mitigate the present ‘H0 tension’. First, we compare local peculiar velocities measured via the galaxy average redshift–magnitude Hubble diagram, $\overline{z}(m)$, with a simple dynamical outflow model based on the average underdensity in the Local Hole. We find that this outflow model is in good agreement with our peculiar velocity measurements from $\overline{z}(m)$ and not significantly inconsistent with Type Ia supernova peculiar velocity measurements from at least the largest previous survey. This outflow could cause an ≈2–3 per cent increase in the local value of Hubble’s constant. Second, considering anisotropic motions, we find that the addition of the outflow model may improve the $\overline{z}(m)$ fit of a bulk flow where galaxies are otherwise at rest in the Local Group frame. We conclude that the Local Hole plus neighbouring overdensities such as the Shapley Supercluster may cause outflow and bulk motions out to ≈150 h−1 Mpc that are cosmologically significant and that need to be taken into account in estimating Hubble’s constant.

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A study of the galaxy redshift distribution towards the cosmic microwave background cold spot in the Corona Borealis supercluster

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2010.16222.x ◽

2010 ◽

Vol 403 (3) ◽

pp. 1531-1540 ◽

Cited By ~ 3

Author(s):

Ricardo Génova-Santos ◽

Carmen Pilar Padilla-Torres ◽

José Alberto Rubiño Martín ◽

Carlos M. Gutiérrez ◽

Rafael Rebolo

Keyword(s):

Cosmic Microwave Background ◽

Cold Spot ◽

Microwave Background ◽

Redshift Distribution ◽

The Galaxy ◽

Galaxy Redshift

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Self-consistent redshift estimation using correlation functions without a spectroscopic reference sample

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz502 ◽

2019 ◽

Vol 485 (3) ◽

pp. 3642-3660 ◽

Cited By ~ 1

Author(s):

Ben Hoyle ◽

Markus Michael Rau

Keyword(s):

Dark Matter ◽

Correlation Functions ◽

Reference Sample ◽

Data Driven ◽

Model Parameters ◽

Redshift Distribution ◽

Self Consistent ◽

The Galaxy ◽

Consistent Manner ◽

Order Of Magnitude

ABSTRACT We present a new method to estimate redshift distributions and galaxy-dark matter bias parameters using correlation functions in a fully data driven and self-consistent manner. Unlike other machine learning, template, or correlation redshift methods, this approach does not require a reference sample with known redshifts. By measuring the projected cross- and auto-correlations of different galaxy sub-samples, e.g. as chosen by simple cells in colour–magnitude space, we are able to estimate the galaxy-dark matter bias model parameters, and the shape of the redshift distributions of each sub-sample. This method fully marginalizes over a flexible parametrization of the redshift distribution and galaxy-dark matter bias parameters of sub-samples of galaxies, and thus provides a general Bayesian framework to incorporate redshift uncertainty into the cosmological analysis in a data-driven, consistent, and reproducible manner. This result is improved by an order of magnitude by including cross-correlations with the cosmic microwave background and with galaxy–galaxy lensing. We showcase how this method could be applied to real galaxies. By using idealized data vectors, in which all galaxy-dark matter model parameters and redshift distributions are known, this method is demonstrated to recover unbiased estimates on important quantities, such as the offset Δz between the mean of the true and estimated redshift distribution and the 68 per cent, 95 per cent, and 99.5 per cent widths of the redshift distribution to an accuracy required by current and future surveys.

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Probing the accelerating Universe with redshift-space distortions in VIPERS

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316010693 ◽

2014 ◽

Vol 11 (S308) ◽

pp. 617-622

Author(s):

Sylvain de la Torre

Keyword(s):

Growth Rate ◽

Large Scale ◽

Large Scale Structure ◽

Einstein Gravity ◽

Accelerating Universe ◽

Data Release ◽

The Galaxy ◽

Redshift Survey ◽

Galaxy Redshift ◽

Clustering Pattern

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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Luminosity Functions from the 2dF Galaxy Redshift Survey

Publications of the Astronomical Society of Australia ◽

10.1071/as04041 ◽

2004 ◽

Vol 21 (4) ◽

pp. 352-355 ◽

Cited By ~ 1

Author(s):

Matthew Colless

Keyword(s):

Spectral Type ◽

Surface Brightness ◽

Luminosity Function ◽

Local Density ◽

Luminosity Functions ◽

The Galaxy ◽

Redshift Survey ◽

Galaxy Redshift ◽

Galaxy Luminosity Function

AbstractA summary of the main results from the 2dF Galaxy Redshift Survey of over 221 000 galaxies on the galaxy luminosity function and its dependence on surface brightness, spectral type, environment, and local density.

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Mapping the Dark Matter Using Weak Lensing

Symposium - International Astronomical Union ◽

10.1017/s0074180900196573 ◽

2005 ◽

Vol 216 ◽

pp. 140-151

Author(s):

Henk Hoekstra

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Gravitational Lensing ◽

Cosmological Parameters ◽

Weak Lensing ◽

Major Step ◽

Redshift Distribution ◽

Panoramic Cameras ◽

The Galaxy ◽

Cosmic Shear

Weak gravitational lensing of distant galaxies by foreground structures has proven to be a powerful tool to study the mass distribution in the universe. The advent of panoramic cameras on 4-m class telescopes has led to a first generation of surveys that already compete with large redshift surveys in terms of the accuracy with which cosmological parameters can be determined. The next surveys, which already have started taking data, will provide another major step forward. At the current level, systematics appear under control, and it is expected that weak lensing will develop into a key tool in the era of precision cosmology, provided we improve our knowledge of the non-linear matter power spectrum and the source redshift distribution. In this review we will briefly describe the principles of weak lensing and discuss the results of recent cosmic shear surveys. We show how the combination of weak lensing and cosmic microwave background measurements can provide tight constraints on cosmological parameters. We also demonstrate the usefulness of weak lensing in studies of the relation between the galaxy distribution and the underlying dark matter distribution (“galaxy biasing”), which can provide important constraints on models of galaxy formation. Finally, we discuss new and upcoming large cosmic shear surveys.

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The Giant Radio Galaxy 0319-45 (MSH 03-43)

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000022979 ◽

1989 ◽

Vol 8 (1) ◽

pp. 81-85 ◽

Cited By ~ 6

Author(s):

P. A. Jones

Keyword(s):

Radio Galaxy ◽

Level Structure ◽

Radio Galaxies ◽

Radio Sources ◽

Low Level ◽

Extended Radio ◽

The Galaxy ◽

Galaxy Redshift ◽

Nearby Source ◽

Extended Radio Source

AbstractThe extended radio source 0319-453 (MSH 03-43) was observed with the Molonglo Observatory Synthesis Telescope as part of a program to study a large sample of southern extragalactic radio sources. The low level structure showed a ridge pointing towards the nearby source 0317-456, which also showed low level structure. It is suggested that the two sources are the asymmetric lobes of a radio galaxy identified with the magnitude 15 peculiar dust-land galaxy AM 0319-452. The galaxy redshift of z = 0.0633 and the radio size of 25.6 arcmin give a projected size of 1.27 Mpc (H = 100 kms−1 Mpc−1). Thus it is one of the largest radio galaxies.

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Hawaii Two-0: high-redshift galaxy clustering and bias

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa432 ◽

2020 ◽

Vol 493 (2) ◽

pp. 2318-2328

Author(s):

Róbert Beck ◽

Conor McPartland ◽

Andrew Repp ◽

David Sanders ◽

István Szapudi

Keyword(s):

High Redshift ◽

Self Organizing Map ◽

Redshift Distribution ◽

Galaxy Clustering ◽

Photometric Redshift ◽

Redshift Galaxy ◽

The Galaxy ◽

Strategic Program ◽

Galaxy Bias ◽

The University

ABSTRACT We perform an analysis of two-point galaxy clustering and galaxy bias using Subaru Hyper-Suprime Cam (HSC) data taken jointly by the Subaru Strategic Program and the University of Hawaii in the Cosmic Evolution Survey (COSMOS) field over an area of 1.8 sq deg. The depth of the data is similar to the ongoing Hawaii Two-0 (H20) optical galaxy survey, thus the results are indicative of future constraints from tenfold area. We measure the angular autopower spectra of the galaxy overdensity in three redshift bins, defined by dropouts from the g, r, and i bands, and compare them to the theoretical expectation from concordance cosmology with linear galaxy bias. We determine the redshift distribution of each bin using a standard template-based photometric redshift method, coupled with a self-organizing map to quantify colour space coverage. We also investigate sources of systematic errors to inform the methodology and requirements for H20. The linear galaxy bias fit results are $b_{\mathrm{gal,g}} = 3.90 \pm 0.33 (\mathrm{stat}) \substack{ +0.64 \\ -0.24 } (\mathrm{sys})$ at redshift z ≃ 3.7, $b_{\mathrm{gal,r}} = 8.44 \pm 0.63 (\mathrm{stat}) \substack{ +1.42 \\ -0.72 } (\mathrm{sys})$ at z ≃ 4.7, and $b_{\mathrm{gal,i}} = 11.94 \pm 2.24 (\mathrm{stat}) \substack{ +1.82 \\ -1.27 } (\mathrm{sys})$ at z ≃ 5.9.

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MusE GAs FLOw and Wind (MEGAFLOW) IV. A two sightline tomography of a galactic wind

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3607 ◽

2019 ◽

Vol 492 (3) ◽

pp. 4576-4588 ◽

Cited By ~ 2

Author(s):

Johannes Zabl ◽

Nicolas F Bouché ◽

Ilane Schroetter ◽

Martin Wendt ◽

Thierry Contini ◽

...

Keyword(s):

Detailed Analysis ◽

Gas Flow ◽

Wind Model ◽

Conical Flow ◽

Distant Galaxy ◽

Velocity Shift ◽

Galactic Winds ◽

Metal Absorption ◽

The Galaxy ◽

First Time

ABSTRACT Galactic outflows are thought to eject baryons back out to the circumgalactic medium. Studies based on metal absorption lines (Mg ii in particular) in the spectra of background quasars indicate that the gas is ejected anisotropically, with galactic winds likely leaving the host in a bi-conical flow perpendicular to the galaxy disc. In this paper, we present a detailed analysis of an outflow from a z = 0.7 ‘green-valley’ galaxy [log (M*/M⊙) = 9.8; $\mbox{SFR}=0.5\, \mathrm{M}_{\odot }\, \mathrm{yr}^{-1}$] probed by two background sources from the MusE GAs FLOw and Wind (MEGAFLOW) survey. Thanks to a fortuitous configuration with a background quasar (SDSSJ1358 + 1145) and a bright background galaxy at z = 1.4, both at impact parameters of $\approx\! 15\, \hbox{kpc}$, we can – for the first time – probe both the receding and approaching components of a putative galactic outflow around a distant galaxy. We measure a significant velocity shift between the Mg ii absorption from the two sightlines ($84\pm 17\, \hbox{km~s$^{-1}$}$), which is consistent with the expectation from our simple fiducial wind model, possibly combined with an extended disc contribution.

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The 2dF Galaxy Redshift Survey as a Cosmological Laboratory

Publications of the Astronomical Society of Australia ◽

10.1071/as04052 ◽

2004 ◽

Vol 21 (4) ◽

pp. 404-407 ◽

Cited By ~ 4

Author(s):

Ofer Lahav

Keyword(s):

Cosmological Parameters ◽

Hubble Constant ◽

Intrinsic Properties ◽

Upper Limit ◽

Matter Model ◽

The Galaxy ◽

Redshift Survey ◽

Galaxy Redshift ◽

Galaxy Population ◽

Dark Matter Model

AbstractThe 2dF Galaxy Redshift Survey (2dFGRS) of 230 000 redshifts of nearby (z ~ 0.1) galaxies is now complete. It has allowed the 2dFGRS Team and others to estimate fundamental cosmological parameters and to study galaxy intrinsic properties. Here we highlight three recent key results from the survey: (a) an upper limit of about 2 eV on the total mass of the three neutrino flavours, and an intriguing reasonable fitting of the 2dFGRS power spectrum to a Mixed Dark Matter model without a Cosmological Constant but with a low Hubble constant; (b) the bimodality of the galaxy population in both spectral parameterisation and in colour; and (c) the clustering of different galaxy types and evidence for relative stochastic biasing.

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