We discuss the effects on the cosmic microwave background (CMB), cosmic infrared background (CIB), and thermal Sunyaev-Zeldovich effect due to the peculiar motion of an observer with respect to the CMB rest frame, which induces boosting effects. After a brief review of the current observational and theoretical status, we investigate the scientific perspectives opened by future CMB space missions, focussing on the Cosmic Origins Explorer (CORE) proposal. The improvements in sensitivity offered by a mission like CORE, together with its high resolution over a wide frequency range, will provide a more accurate estimate of the CMB dipole. The extension of boosting effects to polarization and cross-correlations will enable a more robust determination of purely velocity-driven effects that are not degenerate with the intrinsic CMB dipole, allowing us to achieve an overall signal-to-noise ratio of 13; this improves on the Planck detection and essentially equals that of an ideal cosmic-variance-limited experiment up to a multipole ℓ2000. Precise inter-frequency calibration will offer the opportunity to constrain or even detect CMB spectral distortions, particularly from the cosmological reionization epoch, because of the frequency dependence of the dipole spectrum, without resorting to precise absolute calibration. The expected improvement with respect to COBE-FIRAS in the recovery of distortion parameters (which could in principle be a factor of several hundred for an ideal experiment with the CORE configuration) ranges from a factor of several up to about 50, depending on the quality of foreground removal and relative calibration. Even in the case of 1 % accuracy in both foreground removal and relative calibration at an angular scale of 1-, we find that dipole analyses for a mission like CORE will be able to improve the recovery of the CIB spectrum amplitude by a factor 17 in comparison with current results based on COBE-FIRAS. In addition to the scientific potential of a mission like CORE for these analyses, synergies with other planned and ongoing projects are also discussed.
Bibliographical noteFunding Information:
Partial support by ASI/INAF Agreement 2014-024-R.1 for the Planck LFI Activity of Phase E2 and by ASI through the contract I-022-11-0 LSPE is acknowledged. C.H.-M. acknowledges financial support of the Spanish Ministry of Economy and Competitiveness via I+D project AYA-2015-66211-C2-2-P. J.G.N. acknowledges financial support from the Spanish MINECO for a Ramon y Cajal fellowship (RYC-2013-13256) and the I+D 2015 project AYA2015-65887-P (MINECO/FEDER). C.J.M. is supported by an FCT Research Professorship, contract reference IF/00064/2012, funded by FCT/MCTES (Portugal) and POPH/FSE (EC). M.Q. is supported by the Brazilian research agencies CNPq and FAPERJ. We acknowledge the use of the ESA Planck Legacy Archive. Some of the results in this paper have been derived using the HEALPix package. The use of the computational cluster at INAF-IASF Bologna is acknowledged. It is a pleasure to thank Arpine Kozmanyan for useful discussions on the CosmoMC sampler.
© 2018 IOP Publishing Ltd and Sissa Medialab.
- CMBR experiments
- CMBR theory
- high redshift galaxies