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Title: Probing the Dark Flow signal in WMAP 9 yr and PLANCK cosmic microwave background maps
Author: Fernando Atrio-Barandela, Alexander Kashlinsky, Harald Ebeling, Dale J. Fixsen, Dale Kocevski

The "dark flow" dipole is a statistically significant dipole found at the position of galaxy clusters in filtered maps of Cosmic Microwave Background (CMB) temperature anisotropies. The dipole measured in WMAP 3, 5 and 7 yr data releases was roughly aligned with the all-sky CMB dipole and correlated with cluster X-ray luminosity. We analysed the final WMAP 9 yr and the first Planck data releases using a catalogue of 980 clusters outside the Kp0 mask to test our earlier findings. The dipoles measured on these new data sets are fully compatible with our earlier estimates, being similar in amplitude and direction to our previous results and in disagreement with the results of an earlier study by the Planck Collaboration. Further, in Planck data dipoles are independent of frequency, ruling out the Thermal Sunyaev-Zeldovich as the source of the effect. The signal is dominated by the most massive clusters, with a statistical significance better than 99%, slightly larger than in WMAP. Since both data sets differ in foreground contributions, instrumental noise and other systematics, the agreement between WMAP and Planck dipoles argues against them being due to systematic effects in either of the experiments.

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Blobrana


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Blow for 'dark flow' in Planck's new view of the cosmos

A potential portal to other universes seems to have closed. The sharpest map yet made of light from the infant universe shows no evidence of "dark flow" - a stream of galaxy clusters rushing in the same direction that hinted at the existence of a multiverse.
That is the conclusion of 175 scientists working with data from the European Space Agency's Planck spacecraft. But champions of dark flow are not ready to give up yet, including one Planck scientist who says his team's analysis is flawed. 
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Blobrana


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A new study from UB contradicts the dark-flow theory, showing that exploding stars in different parts of the universe do not appear to be moving in sync.
Working with data on 557 such stars, called supernovae, UB scientists deduced that while the supernovae closest to Earth all shared a common motion in one direction, supernovae further out were heading somewhere else. The difference in motion became pronounced for stars 680 million or more light years away from Earth.
An article announcing the research results will appear in a forthcoming edition of the peer-reviewed Journal of Cosmology and Astroparticle Physics.
Though the findings disagree with the "dark-flow" hypothesis, they coincide with the predictions of another model of the universe: Lambda-Cold Dark Matter, the standard model of cosmology.
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Blobrana


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Mysterious Cosmic 'Dark Flow' Tracked Deeper into Universe

Distant galaxy clusters mysteriously stream at a million miles per hour along a path roughly centred on the southern constellations Centaurus and Hydra. A new study led by Alexander Kashlinsky at NASA's Goddard Space Flight Centre in Greenbelt, Md., tracks this collective motion -- dubbed the "dark flow" -- to twice the distance originally reported.
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