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Related papers: Studying the Peculiar Velocity Bulk Flow in a Spar…

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Peculiar velocities are one of the only probes of very large-scale mass density fluctuations in the nearby Universe. We present new "minimal variance" bulk flow measurements based upon the "First Amendment" compilation of 245 Type Ia…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Stephen J. Turnbull , Michael J. Hudson , Hume A. Feldman , Malcolm Hicken , Robert P. Kirshner , Richard Watkins

Context. Our Local Group of galaxies appears to be moving relative to the cosmic microwave background with the source of the peculiar motion still uncertain. While in the past this has been studied mostly using galaxies as distance…

We study large-scale coherent motion in our universe using the existing Type IA supernovae data. If the recently observed bulk flow is real, then some imprint must be left on supernovae motion. We run a series of Monte Carlo Markov Chain…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 De-Chang Dai , William H. Kinney , Dejan Stojkovic

We present the Democratic Samples of Supernovae (DSS), a compilation of 775 low-redshift Type Ia and II supernovae (SNe Ia & II), of which 137 SN Ia distances are derived via the newly developed snapshot distance method. Using the objects…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-26 Benjamin E. Stahl , Thomas de Jaeger , Supranta S. Boruah , WeiKang Zheng , Alexei V. Filippenko , Michael J. Hudson

The peculiar velocity field offers a unique way to probe dark matter density field on large scales at low redshifts. In this work, we have compiled a new sample of 465 peculiar velocities from low redshift $(z < 0.067)$ Type Ia supernovae.…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-05 Supranta S. Boruah , Michael J. Hudson , Guilhem Lavaux

We re-analyze the detectability of large scale dark flow (or local bulk flow) with respect to the CMB background based upon the redshift-distance relation for Type Ia supernovae (SN Ia). We made two independent analyses: one based upon…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-19 G. J. Mathews , B. Rose , P. Garnavich , D. Yamazaki , T. Kajino

We study the bulk flow of the local universe using Type Ia supernova data by considering a class of cosmological model which is spatially flat,(FRW) space-times and contains cold dark matter and $Q$ component (QCDM models) of the fluid as a…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-31 A. Salehi , M. Yarahmadi , S. Fathi

The question of the transition to global isotropy from our anisotropic local Universe is studied using the Union 2 catalogue of Type Ia supernovae (SNe Ia). We construct a "residual" statistic sensitive to systematic shifts in their…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jacques Colin , Roya Mohayaee , Subir Sarkar , Arman Shafieloo

We measure the bulk flow of the local Universe using the 6dF Galaxy Survey peculiar velocity sample (6dFGSv), the largest and most homogeneous peculiar velocity sample to date. 6dFGSv is a Fundamental Plane sample of $\sim10^4$ peculiar…

We have compared the bulk flow of recent large-scale peculiar velocity surveys (SMAC, SC, Lauer and Postman, Willick, EFAR and Tonry's SNIa sample) to each other, allowing for the errors due to sparse sampling. We conclude that, contrary to…

Astrophysics · Physics 2007-05-23 Michael J Hudson

It has been argued recently that the galaxy peculiar velocity field provides evidence of excessive power on scales of $50\hmpc$, which seems to be inconsistent with the standard $\Lambda$CDM cosmological model. We discuss several…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Yin-Zhe Ma , Douglas Scott

Peculiar velocity surveys have non-uniform spatial distributions of tracers, so that the bulk flow estimated from them does not correspond to that of a simple volume such as a sphere. Thus bulk flow estimates are generally not strictly…

Astrophysics · Physics 2010-11-24 Richard Watkins , Hume A. Feldman , Michael J. Hudson

Type Ia supernovae have only recently been employed to measure the peculiar motions of galaxies. The great distances to which SNe Ia can be seen makes them particularly well-suited to constraining large-scale velocity flows. The high…

Astrophysics · Physics 2007-05-23 Adam G. Riess

A maximum-likelihood method, tested as an unbiased estimator from numerical simulations, is used to estimate cosmic bulk flow from peculiar velocity surveys. The likelihood function is applied to four observational catalogues (ENEAR, SFI++,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Yin-Zhe Ma , Jun Pan

We test the isotropy of the local Universe using low redshift supernova data from various catalogs and the non-parametric method of smoothed residuals. Using a recently developed catalog which combines supernova data from various surveys,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Stephen Appleby , Arman Shafieloo , Andrew Johnson

The {\em bulk flow} in the Local Universe is a collective phenomenon due to the peculiar motions of matter structures, which, instead of moving in random directions, appears to follow an approximate dipole velocity flow. We apply a…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-04 Maria Lopes , Armando Bernui , Camila Franco , Felipe Avila

We study the implications of a recent estimate of the bulk flow of a sample of galaxies containing supernovae type Ia by Riess, Press, and Kirshner. We find that their results are quite consistent with power spectra from several currently…

Astrophysics · Physics 2009-10-28 Richard Watkins , Hume A. Feldman

I address the following issues: All bulk velocity measurements (but one) are consistent with our standard gravitational instability theory. New accurate data and reconstruction methods allow high-resolution dynamical analysis nearby,…

Astrophysics · Physics 2007-05-23 Avishai Dekel

Separating the components of redshift due to expansion and peculiar motion in the nearby universe ($z<0.1$) is critical for using Type Ia Supernovae (SNe Ia) to measure the Hubble constant ($H_0$) and the equation-of-state parameter of dark…

We revisit the effect of peculiar velocities on low-redshift type Ia supernovae. Velocities introduce an additional guaranteed source of correlations between supernova magnitudes that should be considered in all analyses of nearby supernova…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-18 Dragan Huterer , Daniel L. Shafer , Fabian Schmidt
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