A Measurement of Large-Scale Peculiar Velocities of Clusters of Galaxies: Results and Cosmological Implications

By A. Kashlinsky, F. Atrio-Barandela, D. Kocevski, H. Ebeling. 2008

302 citations recorded by the source corpus.

Peculiar velocities of clusters of galaxies can be measured by studying the fluctuations in the cosmic microwave background (CMB) generated by the scattering of the microwave photons by the hot X-ray-emitting gas inside clusters. While for individual clusters such measurements result in large errors, a large statistical sample of clusters allows one to study cumulative quantities dominated by the overall bulk flow of the sample with the statistical errors integrating down. We present results from such a measurement using the largest all-sky X-ray cluster catalog combined to date and the 3 yr WMAP CMB data. We find a strong and coherent bulk flow on scales out to at least ≳300 h−1 Mpc, the limit of our catalog. This flow is difficult to explain by gravitational evolution within the framework of the concordance ΛCDM model and may be indicative of the tilt exerted across the entire current horizon by far-away pre-inflationary inhomogeneities.

Subfields: Astronomy and Astrophysics, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/d4a86f35e01009a9660b87584d6c87f54d0fb5f2

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. H. Ebeling
2. S. Allen
3. A. Mantz
4. M. Hudson
5. R. Watkins
6. H. Feldman
7. August E. Evrard
8. Roya Mohayaee

In Statistical and Nonlinear Physics

1. R. Watkins
2. M. Hudson
3. H. Feldman
4. H. Ebeling
5. August E. Evrard
6. S. Allen
7. D. Kocevski
8. A. Shafieloo

Citations in the corpus

• The 2M++ galaxy redshift catalogue (2011, background): “Recently, several intriguing measurements (Kashlinsky et al. 2008; Watkins et al. 2009; Lavaux et al. 2010; Kashlinsky et al. 2010; Feldman et al. 2010) of the mean or “bulk” flow on scales larger than 100h−1 Mpc suggest a high velocity of our local ∼ 100 h−1 Mpc volume with respect to the Cosmic…”
• Cosmic flows on 100 h−1 Mpc scales: standardized minimum variance bulk flow, shear and octupole moments (2009, background): “Recently, Kashlinsky et al. (2008, 2010) and Atrio-Barandela et al. (2010) claimed to have detected a dipole in filtered WMAP CMB temperature maps measured at the locations of rich clusters.”
• A NEW MEASUREMENT OF THE BULK FLOW OF X-RAY LUMINOUS CLUSTERS OF GALAXIES (2009, background): “Our discovery of a coherent large-scale flow of galaxy clusters with significantly larger amplitude than expected out to 300 Mpc (Kashlinsky et al. 2008, 2009, KABKE1,2) represents a challenge to the gravitational instability paradigm.”
• Cosmological Parameters from Observations of Galaxy Clusters (2011, result): “Although some initial results based on such measurements have been reported (e.g. Kashlinsky et al. 2008, 2010; Keisler 2009; Osborne et al. 2010), the technique has not yet reached the maturity of those discussed above and is not discussed further in this review.”
• The X-ray brightest clusters of galaxies from the Massive Cluster Survey (2010, background): “…Crawford et al. 1995, 1999; Ebeling et al. 1997; Hudson & Ebeling 1997; Edge et al. 1999, Smith et al. 2001; Schuecker et al. 2001; Allen et al. 2003; Kocevski et al. 2004, 2006; Smith et al. 2005; Stanek et al. 2006; Kocevski & Ebeling 2006; AtrioBarandela et al. 2008; Kashlinsky et al. 2008).”
• Consistently large cosmic flows on scales of 100 h−1 Mpc: a challenge for the standard ΛCDM cosmology (2008, methodology): “Our bulk flow result is in excellent directional agreement (6◦) with that found by Kashlinsky et al. (2008b).”
• Cosmic flows in the nearby universe from Type Ia supernovae (2011, background): “An alternative explanation for the bulk flow has been proposed, namely that the CMB temperature dipole, or part thereof, is intrinsic and does not represent the peculiar velocity of the LG (A ‘tilted’ Universe: Turner 1991; Kashlinsky et al. 2008; Ma, Gordon & Feldman 2011).”
• SEVEN-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: COSMOLOGICAL INTERPRETATION (2010, unknown): “…et al. 2003; Hernández-Monteagudo & Rubiño-Mart́ın 2004; Hernández-Monteagudo et al. 2004; Myers et al. 2004; Afshordi et al. 2005; Lieu et al. 2006; Bielby & Shanks 2007; Afshordi et al. 2007; Atrio-Barandela et al. 2008; Kashlinsky et al. 2008; Diego & Partridge 2009; Melin et al. 2010).”
• A structure in the early Universe at z ∼ 1.3 that exceeds the homogeneity scale of the R-W concordance cosmology (2012, background): “Such mass concentrations could conceivably be associated with the cosmic (dark) flows on scales of ∼ 100-1000 Mpc as reported by, for example, Kashlinsky et al. (2008); Watkins, Feldman & Hudson (2009); Feldman, Watkins & Hudson (2010); and Kashlinsky et al. (2010).”
• Probing the anisotropic local Universe and beyond with SNe Ia data (2010, methodology): “…the discrepancy between the luminosity distance of Union 2 SNe Ia and the value predicted by the standard CDM model, for z < 0.06 (top panel) 2 Kashlinsky et al. (2008, 2010) have reported an even faster coherent flow out to at least ∼800 Mpc, using measurements of the kinematic Sunyaev–…”
• Probing cosmic isotropy with a new X-ray galaxy cluster sample through the LX–T scaling relation (2020, background): “…Tiwari & Nusser 2016; Bengaly et al. 2018, 2019; Colin et al. 2019), gamma-ray bursts (Řípa & Shafieloo 2017; Andrade et al. 2019), peculiar velocities of galaxy clusters (Kashlinsky et al. 2008, 2010, 2011; Watkins et al. 2009; Atrio-Barandela et al. 2015) and of SNIa (Appleby et al. 2015) etc.”