CMB part II

1
CMB part II
2
Polarization of the CMB
General applies to primary anisotropy and
reionization induced polarization
no polarization if photon sees an isotropic
radiation field
polarized radiation by radiation from one
direction
3
Polarization of the CMB
General applies to primary anisotropy and
reionization induced polarization
Needed for polarization component of radiation
where different amplitude of radiation are
coming at the electron at 90 degrees between
then this is the property of quarupole
distribution
4
Polarization of the CMB
Polarization in the primary anisotropies
single mode potential fluctuation
Where does the quarupole come from during
recombination? Convergent velocity field in
potenrial wells/peaks as the fluid
oscillates. Then, have to get the projection of
these on the plane of the observers sky. Most
polarization will be seen on scales that
correspond to maximum fluid velocity at 90deg
away from maximum fluid compression. Polarization
peaks will be between the temperature fluctuation
peaks.
5
Polarization fluctuations
peaks in temp. fluct. correspond to troughs in
pol. fluct.
Primary polarization and reionization pol.
Quadrupole radiation field is that of the CMB
primary anisotropies, z10
6
Observed polarization correlation