Abstract
Based on cosmic microwave background (CMB) maps from the
2013 Planck Mission data release, this paper presents the
detection of the integrated Sachs-Wolfe (ISW) effect,
that is, the correlation between the CMB and large-scale
evolving gravitational potentials. The significance of
detection ranges from 2 to 4s, depending on which method
is used. We investigated three separate approaches, which
essentially cover all previous studies, and also break
new ground. (i) We correlated the CMB with the Planck
reconstructed gravitational lensing potential (for the
first time). This detection was made using the
lensing-induced bispectrum between the low-l and high-l
temperature anisotropies; the correlation between lensing
and the ISW effect has a significance close to 2.5s. (ii)
We cross-correlated with tracers of large-scale
structure, which yielded a significance of about 3s,
based on a combination of radio (NVSS) and optical (SDSS)
data. (iii) We used aperture photometry on stacked CMB
fields at the locations of known large-scale structures,
which yielded and confirms a 4s signal, over a broader
spectral range, when using a previously explored
catalogue, but shows strong discrepancies in amplitude
and scale when compared with expectations. More recent
catalogues give more moderate results that range from
negligible to 2.5s at most, but have a more consistent
scale and amplitude, the latter being still slightly
higher than what is expected from numerical simulations
within ?CMD. Where they can be compared, these
measurements are compatible with previous work using data
from WMAP, where these scales have been mapped to the
limits of cosmic variance. Planck's broader frequency
coverage allows for better foreground cleaning and
confirms that the signal is achromatic, which makes it
preferable for ISW detection. As a final step we used
tracers of large-scale structure to filter the CMB data,
from which we present maps of the ISW temperature
perturbation. These results provide complementary and
independent evidence for the existence of a dark energy
component that governs the currently accelerated
expansion of the Universe.
Original language | English |
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Article number | A19 |
Number of pages | 23 |
Journal | Astronomy and Astrophysics |
Volume | 571 |
DOIs | |
Publication status | Published - 2014 |
MoE publication type | A1 Journal article-refereed |
Keywords
- cosmic background radiation
- large-scale structure of Universe
- dark energy
- galaxies
- data analysis