Cross-correlation power spectra and cosmic birefringence of the CMB via photon-neutrino interaction

Abstract

In the context of the standard model of particles, the weak interaction of cosmic microwave background (CMB) and cosmic neutrino background (CνB), can generate non-vanishing TB and EB power spectra in the order of one loop forward scattering, in the presence of scalar perturbation, which is in contrast with the standard scenario cosmology. Comparing our results with the current experimental data may provide, significant information about the nature of CνB, including CMB-CνB forward scattering for TB, TE, and EB power spectra. To this end, different cases were studied, including Majorana CνB and Dirac CνB. On the other hand, it was shown that the mean opacity due to cosmic neutrino background could behave as an anisotropic birefringent medium and change the linear polarization rotation angle. Considering the contributions from neutrino and anti-neutrino forward scattering with CMB photons (in the case of Dirac neutrino), we introduce relative neutrino and anti-neutrino density asymmetry (δν = Δnν /nν = nν -nν̅ /nν ). Then, using the cosmic birefringence angle reported by the Planck data release β = 0.30° ± 0.11° (68%C.L.), some constraints can be put on δν . Also, the value of cosmic birefringence due to Majorana CνB medium is estimated at about β| ν ≃ 0.2 rad. In this respect, since Majorana neutrino and anti-neutrino are exactly the same, both CB contributions will be added together. However, this value is at least two orders larger than the cosmic birefringence angle reported by the Planck data release, β = 0.30° ± 0.11° (68%C.L.). Finally, we shortly discussed this big inconsistency. It is noteworthy that to calculate the contribution of photon-neutrino forward scattering for cosmic birefringence, we just consider the standard model of particles and the standard scenario of cosmology.

Can we explain cosmic birefringence without a new light field beyond Standard Model?

“…As mentioned above, this operator is reduced to c EB E • B with ċEB = J 0 . Roughly estimating ċEB ∼ Hc EB with the Hubble parameter H, we see that the induced ICB angle β could be comparable to the reported value β ∼ O(0.1 • ) for the neutrino background J 0 ∼ n ν due to the significant enhancement factor H −1 [61][62][63]83]. However, in this scenario, the symmetry allows the photon mass in the vacuum.…”

“…For example, a Stueckelberg scalar makes it possible to add the photon mass term A µ A µ in the action. When a Stueckelberg field is given by a two-form field B µν [61][62][63]83], we can add the BF term B µν F µν , which is known to induce the photon mass [84]. Since the experimental upper bound on the photon mass is O(10 −18 ) eV [85,86], we need a mechanism to forbid or suppress these operators.…”

Generation of the CMB cosmic birefringence through axion-like particles, sterile and active neutrinos

“…In this section, we first study right-handed sterile neutrinos (according to the new scenario [44]) whose coupling to the photon would induce a rotation of the polarization plane of the CMB, and try to investigate their properties through CMB birefringence. Next, we re-analyze some results of [24], regarding the contribution of CνB-CMB interaction in producing the CB angle.…”

“…For instance, authors in [23] proposed a CPT-even sixdimensional effective Lagrangian and considered the effect of neutrino density asymmetry on CB angle. Moreover, the weak interaction of the CMB and cosmic neutrino background (CνB) can produce non-vanishing EB power spectra at the level of one loop forward scattering in the presence of scalar perturbation, which generates part of the CB angle [24]. In addition, the impact of dipolar dark matter (DM), as well as sterile neutrino DM interaction with photons in producing the CB effect of the CMB has been studied by authors in [25].…”

“…Next, we provide a short review of the generation of the CB angle due to the CνB with the CMB following Ref. [24]. Section 4 is devoted to studying the CB effect due to the interaction between the CMB photons and ALPs.…”