Detectability of Gravitational Lensing Effect on the Two-point Correlation Function of Hotspots in the CMB maps

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Accepted by ApJ. Received June 14, Accepted August 24. 24 pages including 9 figures

Scientific paper

10.1086/318305

We present quantitative investigations of the weak lensing effect on the two-point correlation functions of local maxima (hotspots), $\xipk(\theta)$, in the cosmic microwave background (CMB) maps. The lensing effect depends on the projected mass fluctuations between today and the redshift $z_{\rm rec}\approx1100$. If adopting the Gaussian assumption for the primordial temperature fluctuations field, the peak statistics can provide an additional information about the intrinsic distribution of hotspots that those pairs have some characteristic separation angles. The weak lensing then redistributes hotspots in the observed CMB maps from the intrinsic distribution and consequently imprints non-Gaussian signatures onto $\xipk(\theta)$. Especially, since the intrinsic $\xipk(\theta)$ has a pronounced depression feature around the angular scale of $\theta\approx 70'$ for a flat universe, the weak lensing induces a large smoothing at the scale. We show that the lensing signature therefore has an advantage to effectively probe mass fluctuations with large wavelength modes around $\lambda\approx 50 h^{-1}{\rm Mpc}$. To reveal the detectability, we performed numerical experiments with specifications of {\em MAP} and {\em Planck Surveyor} including the instrumental effects of beam smoothing and detector noise. It is then found that our method can successfully provide constraints on amplitude of the mass fluctuations and cosmological parameters in a flat universe with and without cosmological constant, provided that we use maps with 65% sky coverage expected from Planck.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Detectability of Gravitational Lensing Effect on the Two-point Correlation Function of Hotspots in the CMB maps does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Detectability of Gravitational Lensing Effect on the Two-point Correlation Function of Hotspots in the CMB maps, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Detectability of Gravitational Lensing Effect on the Two-point Correlation Function of Hotspots in the CMB maps will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-346567

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.