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Related papers: Measuring Omega with Galaxy Streaming Velocities

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The geometry of Freedman-Roberston-Walker cosmological models is fixed by the mass density parameter, Omega_M, and the cosmological constant, Omega_Lambda. The classical volume-redshift cosmological relation is a sensitive…

Astrophysics · Physics 2007-05-23 R. G. Carlberg

The reconstruction of the peculiar velocity field from the 1.936~Jy iras selected sample of galaxies is compared to a similar reconstruction from an optically selected sample. A general method for combining different samples to reconstruct…

Astrophysics · Physics 2015-06-24 Wolfram Freudling , Luiz Nicolaci da Costa , Paulo S. Pellegrini

We report on the first measurement of the average mass and mass-to-light ratio of galaxy groups by analysing the weak lensing signal induced by these systems. The groups, which have velocity dispersions of 50-400 km/s, have been selected…

Our peculiar velocity imprints a dipole on galaxy density maps derived from redshift surveys. The dipole gives rise to an oscillatory signal in the multipole moments of the observed power spectrum which we indicate as the…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-04 Mohamed Yousry Elkhashab , Cristiano Porciani , Daniele Bertacca

Peculiar velocities are an important probe of the growth rate of mass density fluctuations in the Universe. Most previous studies have focussed exclusively on measuring peculiar velocities at intermediate ($0.2 < z < 1$) redshifts using…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Michael J. Hudson , Stephen J. Turnbull

This work investigates the use of a well-known empirical correlation between the velocity dispersion, metallicity, and luminosity in H beta of nearby HII galaxies to measure the distances to HII-like starburst galaxies at high redshifts.…

We study the expansion of the nearby Universe using a sample of Type Ia supernovae at redshifts below 0.08. These supernovae allow peculiar velocities to be measured at unprecedented precision. We have investigated in detail the possibility…

Astrophysics · Physics 2007-05-23 Lifan Wang

We have developed a technique to systematically discover and study high-redshift supernovae that can be used to measure the cosmological parameters. We report here results based on the initial seven of >28 supernovae discovered to date in…

We investigate the feasibility of determining the pairwise velocity dispersion (PVD) for Lyman Break Galaxies (LBGs), and of using this quantity as a discriminator among theoretical models. We find that when the Two Point Correlation…

Astrophysics · Physics 2009-11-07 D. H. Zhao , Y. P. Jing , G. Boerner

We derive oxygen abundances for a sample of 40 luminous (M_{B} < -19), star-forming, mostly disk, field galaxies with redshifts in the range 0.2 < z < 0.8$, with a median of <z> = 0.45. Oxygen abundances, relative to hydrogen, of the…

Astrophysics · Physics 2009-11-11 M. Mouhcine , S. P. Bamford , A. Aragon-Salamanca , O. Nakamura

Via the magnification bias, gravitational lensing by large-scale structures causes angular cross-correlations between distant quasars and foreground galaxies on angular scales of arc minutes and above. We investigate the three-point…

Astrophysics · Physics 2007-05-23 Brice Menard , Matthias Bartelmann , Yannick Mellier

The purpose of this work is to make available new gas-phase oxygen abundance measurements for a serendipitous sample of 27 galaxies with redshift 0.35<z<0.52. We measured the equivalent widths of the [O II]{\lambda}3727, H{\beta}, and [O…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 L. Morelli , V. Calvi , A. Cardullo , A. Pizzella , E. M. Corsini , E. Dalla Bontà

The systemic velocity or redshift of galaxies is a convenient tool to calculate their distances in the absence of primary methods, but the uncertainties on these flow distances may be substantial due to galaxy peculiar motions. Here, we…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-23 Konstantin Haubner , Federico Lelli , Enrico Di Teodoro , Francis Duey , Stacy McGaugh , James Schombert

The gravitational potential well of an $M>10^{13}$ $M_\odot$ galaxy will lead to a gravitational redshift differential of order 1 km/s between the galaxy core and its outskirts. Current surveys of massive galaxies with spatially resolved…

Astrophysics of Galaxies · Physics 2019-01-21 Hongyu Zhu , Shadab Alam , Rupert A. C. Croft , Shirley Ho , Elena Giusarma , Alexie Leauthaud , Michael Merrifield

This work presents a study of galactic outflows driven by stellar feedback. We extract main sequence disc galaxies with stellar mass $10^9\le$ M$_{\star}/$M$_{\odot} \le 5.7\times10^{10}$ at redshift $z=0$ from the highest resolution…

It is shown that the average magnitude - redshift diagram for a magnitude-limited sample of galaxies can be effectively used for mapping galaxy velocity field. This new approach is quantitatively introduced and applied to the CfA, ESO/LV…

Astrophysics · Physics 2016-06-08 Jacek Choloniewski

Studies of the distribution and evolution of galaxies are of fundamental importance to modern cosmology; these studies, however, are hampered by the complexity of the competing effects of spectral and density evolution. Constructing a…

Astrophysics · Physics 2009-10-31 R. J. Brunner , A. J. Connolly , A. S. Szalay

The evolution of the galaxy cluster abundance depends sensitively on the value of the cosmological density parameter, Omega_0. Recent ASCA data are used to quantify this evolution as measured by the X-ray temperature function. A chi^2…

Astrophysics · Physics 2009-10-30 V. R. Eke , S. Cole , C. S. Frenk , J. P. Henry

The accuracy and robustness of a simple method to estimate the total mass profile of a galaxy is tested using a sample of 65 cosmological zoom-simulations of individual galaxies. The method only requires information on the optical surface…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 N. Lyskova , E. Churazov , I. Zhuravleva , T. Naab , L. Oser , O. Gerhard , X. Wu

The Galactic bulge shows a double red clump in sight lines with |b| > 5 deg and -3 deg < l < 4 deg. It is interpreted as a signature of an X-shaped structure seen almost edge-on. We measure the proper motions of the stars belonging to the…

Astrophysics of Galaxies · Physics 2015-06-15 R. Poleski , A. Udalski , A. Gould , M. K. Szymanski , I. Soszynski , M. Kubiak , G. Pietrzynski , K. Ulaczyk , L. Wyrzykowski
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