Dipole leakage and low CMB multipoles

@article{Das2014DipoleLA,
  title={Dipole leakage and low CMB multipoles},
  author={Santanu Das and Tarun Souradeep},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
  year={2014},
  volume={484},
  pages={012029}
}
A number of studies of WMAP-7 have highlighted that the power at the low multipoles in CMB power spectrum is lower than their theoretically predicted value. Angular correlation between the orientations of these low multipoles have also been discovered. While these observations may have cosmological ramification, it is important to investigate possible observational artifacts that can mimic them. The CMB dipole, which is much higher than the quadrupole, can get leaked to the higher multipoles… Expand

Figures and Tables from this paper

Estimating SI violation in CMB due to non-circular beam and complex scan in minutes
Mild, unavoidable deviations from circular-symmetry of instrumental beams along with scan strategy can give rise to measurable Statistical Isotropy (SI) violation in Cosmic Microwave Background (CMB)Expand
sitoolbox: A package for Bayesian estimation of the isotropy violation in the CMB sky
  • Santanu Das
  • Physics
  • Monthly Notices of the Royal Astronomical Society
  • 2019
The standard model of cosmology predicts a statistically isotropic (SI) cosmic microwave background (CMB) sky. However, the SI violation signals are always present in an observed sky-map. DifferentExpand

References

SHOWING 1-10 OF 17 REFERENCES
CMB power spectrum estimation using noncircular beams
The measurements of the angular power spectrum of the Cosmic Microwave Background (CMB) anisotropy have proved crucial to the emergence of cosmology as a precision science in recent years. In thisExpand
Induced CMB quadrupole from pointing offsets
Recent claims in the literature have suggested that the WMAP quadrupole is not primordial in origin, and arises from an aliasing of the much larger dipole field because of incorrect satelliteExpand
Double inflation and the low CMB quadrupole
Recent released WMAP data show a low value of quadrupole in the CMB temperature fluctuations, which confirms the early observations by COBE. In this Letter we consider a model of two inflatons withExpand
Cosmic microwave background power spectrum estimation with non-circular beam and incomplete sky coverage
Over the last decade, measurements of the cosmic microwave background (CMB) anisotropy have spearheaded the remarkable transition of cosmology into a precision science. However, addressing theExpand
Removing beam asymmetry bias in precision CMB temperature and polarization experiments
Asymmetric beams can create significant bias in estimates of the power spectra from cosmic microwave background (CMB) experiments. With the temperature power spectrum many orders of magnitudeExpand
SEVEN-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP *) OBSERVATIONS: ARE THERE COSMIC MICROWAVE BACKGROUND ANOMALIES?
A simple six-parameter ?CDM model provides a successful fit to WMAP data. This holds both when the WMAP data are analyzed alone or in combination with other cosmological data. Even so, it isExpand
Three Year Wilkinson Microwave Anistropy Probe (WMAP) Observations: Polarization Analysis
The Wilkinson Microwave Anisotropy Probe (WMAP) has mapped the entire sky in five frequency bands between 23 and 94 GHz with polarization sensitive radiometers. We present three-year full-sky maps ofExpand
Elliptical beams in CMB temperature and polarization anisotropy experiments: An analytic approach
We present an analytic approach to the estimation of beam asymmetry effects in cosmic microwave background (CMB) temperature and linear polarization anisotropy experiments. We derive via perturbativeExpand
Measuring Planck beams with planets
Aims. Accurate measurement of the cosmic microwave background (CMB) anisotropy requires precise knowledge of the instrument beam. We explore how well the Planck beams will be determined fromExpand
High resolution foreground cleaned CMB map from WMAP
We perform an independent foreground analysis of the Wilkinson Microwave Anisotropy Probe (WMAP) maps to produce a cleaned cosmic microwave background (CMB) map (available online) useful forExpand
...
1
2
...