Suppressing CMB low multipoles with ISW effect

Understand

Recent results of Planck data reveal that the power in the low multipoles of the CMB angular power spectrum, approximately up to $l=30$, is significantly lower than the theoretically predicted in the best fit $\Lambda$CDM model.

• In this paper we investigate the possibility of invoking the Integrated Sachs-Wolfe (ISW) effect to explain this power deficit at low multipoles.
• The ISW effect that originates from the late time expansion history of the universe is rich in possibilities given the limited understanding of the origin of dark energy (DE).
• It is a common understanding that the ISW effect adds to the power at the low multipoles of the CMB angular power spectrum.