Related papers: CMB $V$ modes from photon-photon forward scatterin…
When a cosmic microwave background (CMB) photon travels from the surface of last scatter through spacetime metric perturbations, the polarization vector may rotate about its direction of propagation. This gravitational rotation is distinct…
When the last electron-photon scattering takes place in a magnetized environment, the degree of circular polarization of the outgoing radiation depends upon the magnetic field strength. After deriving the scattering matrix of the process,…
It is known that in contrast with the E-mode polarization, the B-mode polarization of the Cosmic Microwave Background cannot be generated by the Compton scattering in the case of scalar mode of metric perturbation. However it is possible to…
The changes in the cosmic microwave background (CMB) spectrum seen as an increase of temperature due to a strong magnetic field are determined and their influence on the polarization of the radiation is exhibited. The effect is due to the…
Spectral distortions of the cosmic microwave background (CMB) provide stringent constraints on energy and entropy production in the post-BBN (Big Bang Nucleosynthesis) era. This has been used to constrain dark photon models with COBE/FIRAS…
We study a new contribution to the polarization of the Cosmic Microwave Background induced at the epoch of recombination by the second-order quadrupole moment of the photon distribution. At second order in perturbation theory the quadrupole…
We present a new upper limit on CMB circular polarization from the 2015 flight of SPIDER, a balloon-borne telescope designed to search for $B$-mode linear polarization from cosmic inflation. Although the level of circular polarization in…
CMB foregrounds consist of all radiation between the surface of last scattering and the detectors, which can interfere with the cosmological interpretation of CMB data. Fortunately, in temperature (intensity), even though the foregrounds…
The curl (B) modes of cosmic microwave background (CMB) polarization anisotropies are a unique probe of the primordial background of inflationary gravitational waves (IGWs). Unfortunately, the B-mode polarization anisotropies generated by…
The cosmic microwave background (CMB) spectrum is an extraordinary tool for exploring physics beyond the Standard Model. The exquisite precision of the measurement makes it particularly sensitive to small effects caused by hidden sector…
We discuss fluctuations in the cosmic microwave background (CMB) polarization due to scattering from reionized gas at low redshifts. Polarization is produced by re-scattering of the primordial temperature anisotropy quadrupole and of the…
The linear polarization of the Cosmic Microwave Background (CMB) is highly sensitive to parity-violating physics at the surface of last scattering, which might cause mixing of E and B modes, an effect known as {\it cosmic birefringence}.…
Conventional indirect dark matter (DM) searches look for an excess in the electromagnetic emission from the sky that cannot be attributed to known astrophysical sources. Here, we argue that the photon polarisation is an important feature to…
We evaluate the expected level of foreground contamination to the cosmic microwave background (CMB) polarised radiation, focusing on the diffuse emission from our own Galaxy. In particular, we perform a first attempt to simulate an all sky…
Electron scattering induces a polarization in the cosmic microwave background (CMB) signal measured in the direction of a galaxy cluster due to the presence of a quadrupole component in the CMB temperature distribution. Measuring the…
We use a simple model to investigate the effect of polarized Galactic foreground emission on the ability of planned CMB missions to detect and model CMB polarization. Emission from likely polarized sources (synchrotron and spinning dust)…
Compton scattering of Cosmic Microwave Background (CMB) photons on galaxy cluster electrons produces a linear polarization, which contains some information on the local quadrupole at the cluster location. We use N-body simulations to…
Searching for the signal of primordial gravitational waves in the B-modes (BB) power spectrum is one of the key scientific aims of the cosmic microwave background (CMB) polarization experiments. However, this could be easily contaminated by…
A B-mode polarization signal in the cosmic microwave background (CMB) is widely regarded as smoking gun evidence for gravitational waves produced during inflation. Here, we demonstrate that tensor perturbations sourced during…
Probing primordial curvature perturbations on small scales, beyond those accessible using cosmic microwave background (CMB) primary anisotropies and Lyman-$\alpha$ forest data, remains a major open challenge. Current constraints on the…