Cold imprint of supervoids in the Cosmic Microwave Background re-considered with Planck and BOSS DR10

We analyze publicly available void catalogs of the Baryon Oscillation Spectroscopic Survey Data Release 10 at redshifts $0.4<z<0.7$. The first goal of this paper is to extend the Cosmic Microwave Background stacking analysis of previous spectroscopic void samples at $z<0.4$. In addition, the DR10 void catalog provides the first chance to spectroscopically probe the volume of the Granett et al. (2008) supervoid catalog that constitutes the only set of voids which has shown a significant detection of a cross-correlation signal between void locations and average CMB chill. We found that the positions of voids identified in the spectroscopic DR10 galaxy catalog typically do not coincide with the locations of the Granett et al. supervoids in the overlapping volume, in spite of the presence of large underdense regions of high void-density in DR10. This failure to locate the same structures with spectroscopic redshifts may arise due to systematic differences in the properties of voids detected in photometric and spectroscopic samples. In the stacking measurement, we first find a $\Delta T = - 11.5 \pm 3.7~\mu K$ imprint for 35 of the 50 Granett et al. supervoids available in the DR10 volume. For the DR10 void catalog, lacking a prior on the number of voids to be considered in the stacking analysis, we find that the correlation measurement is fully consistent with no correlation. However, the measurement peaks with amplitude $\Delta T = - 9.8 \pm 4.8~\mu K$ for the a posteriori-selected 44 largest voids of size $R>65~Mpc/h$ that does match in terms of amplitude and number of structures the Granett et al. observation, although at different void positions.Comment: 9 pages, 7 figures, accepted for publication in MNRA

Vibrating-chamber levitation systems

Systems are described for the acoustic levitation of objects, which enable the use of a sealed rigid chamber to avoid contamination of the levitated object. The apparatus includes a housing forming a substantially closed chamber, and means for vibrating the entire housing at a frequency that produces an acoustic standing wave pattern within the chamber

Gravity enhanced acoustic levitation method and apparatus

An acoustic levitation system is provided for acoustically levitating an object by applying a single frequency from a transducer into a resonant chamber surrounding the object. The chamber includes a stabilizer location along its height, where the side walls of the chamber are angled so they converge in an upward direction. When an acoustic standing wave pattern is applied between the top and bottom of the chamber, a levitation surface within the stabilizer does not lie on a horizontal plane, but instead is curved with a lowermost portion near the vertical axis of the chamber. As a result, an acoustically levitated object is urged by gravity towards the lowermost location on the levitation surface, so the object is kept away from the side walls of the chamber

Cross-correlation of WMAP7 and the WISE Full Data Release

We measured the cross-correlation of the Wilkinson Microwave Anisotropy Probe (WMAP) 7 year temperature map and the full sky data release of the Wide-field Infrared Survey Explorer (WISE) galaxy map. Using careful mapmaking and masking techniques we find a positive cross-correlation signal. The results are fully consistent with a Lambda-CDM Universe, although not statistically significant. Our findings are robust against changing the galactic latitude cut from |b|>10 to |b|>20 and no color dependence was detected when we used WMAP Q, V or W maps. We confirm higher significance correlations found in the preliminary data release. The change in significance is consistent with cosmic variance.Comment: 5 pages, 4 figures, Accepted for publication in MNRAS Letter

A Map of the Integrated Sachs-Wolfe Signal from Luminous Red Galaxies

We construct a map of the time derivative of the gravitational potential traced by SDSS Luminous Red Galaxies. The potential decays on large scales due to cosmic acceleration, leaving an imprint on cosmic microwave background (CMB) radiation through the integrated Sachs-Wolfe (ISW) effect. With a template fit, we directly measure this signature on the CMB at a 2-sigma confidence level. The measurement is consistent with the cross-correlation statistic, strengthening the claim that dark energy is indeed the cause of the correlation. This new approach potentially simplifies the cosmological interpretation. Our constructed linear ISW map shows no evidence for degree-scale cold and hot spots associated with supervoid and supercluster structures. This suggests that the linear ISW effect in a concordance Lambda-CDM cosmology is insufficient to explain the strong CMB imprints from these structures that we previously reported.Comment: 9 pages, 12 figures, accepted to ApJ. Updated discussion about redshift cut

The Integrated Sachs-Wolfe Signal from BOSS Super-Structures

Cosmic structures leave an imprint on the microwave background radiation through the integrated Sachs-Wolfe effect. We construct a template map of the linear signal using the SDSS-III Baryon Acoustic Oscillation Survey at redshift 0.43 < z < 0.65. We verify the imprint of this map on the Planck CMB temperature map at the 97% confidence level and show consistency with the density-temperature cross-correlation measurement. Using this ISW reconstruction as a template we investigate the presence of ISW sources and further examine the properties of the Granett-Neyrinck-Szapudi supervoid and supercluster catalogue. We characterise the three-dimensional density profiles of these structures for the first time and demonstrate that they are significant structures. Model fits demonstrate that the supervoids are elongated along the line-of-sight and we suggest that this special orientation may be picked out by the void-finding algorithm in photometric redshift space. We measure the mean temperature profiles in Planck maps from public void and cluster catalogues. In an attempt to maximise the stacked ISW signal we construct a new catalogue of super-structures based upon local peaks and troughs of the gravitational potential. However, we do not find a significant correlation between these structures and the CMB temperature.Comment: Updated to match journal articl

Cross-correlation of WISE Galaxies with the Cosmic Microwave Background

We estimated the cross-power spectra of a galaxy sample from the Wide-field Infrared Survey Explorer (WISE) survey with the 7-year Wilkinson Microwave Anisotropy Probe (WMAP) temperature anisotropy maps. A conservatively-selected galaxy sample covers ~13000sq.deg, with a median redshift of z=0.15. Cross-power spectra show correlations between the two data sets with no discernible dependence on the WMAP Q, V and W frequency bands. We interpret these results in terms of the the Integrated Sachs-Wolfe (ISW) effect: for the |b|>20 deg sample at l=6-87, we measure the amplitude (normalized to be 1 for vanilla LambdaCDM expectation) of the signal to be 3.4+-1.1, i.e., 3.1 sigma detection. We discuss other possibilities, but at face value, the detection of the linear ISW effect in a flat universe is caused by large scale decaying potentials, a sign of accelerated expansion driven by Dark Energy.Comment: 5 pages, 5 figures. Accepted for publication in MNRA

Cosmological Density Fluctuations on 100Mpc Scales and their ISW Effect

We measure the matter probability distribution function (PDF) via counts in cells in a volume limited subsample of the Sloan Digital Sky Survey Luminous Red Galaxy Catalog on scales from $30 h^{-1}$Mpc to $150 h^{-1}$Mpc and estimate the linear Integrated Sachs--Wolfe effect produced by supervoids and superclusters in the tail of the PDF. We characterize the PDF by the variance, $S_3$, and $S_4$, and study in simulations the systematic effects due to finite volume, survey shape and redshift distortion. We compare our measurement to the prediction of $\Lambda$CDM with linear bias and find a good agreement. We use the moments to approximate the tail of the PDF with analytic functions. A simple Gaussian model for the superstructures appears to be consistent with the claim by Granett et al. that density fluctuations on $100 h^{-1}$Mpc scales produce hot and cold spots with $\Delta T \approx 10\mu K$ on the cosmic microwave background.Comment: 9 pages, 9 figures, 2 tables, Updates to match the article accepted to Ap