•The Sunyaev-Zeldovich
Effect:
–Look toward hot
intercluster medium in galaxy clusters…Thomson
scattering can affect the CMBR seen through such a
medium
–Optical thickness is τT = ∫σTne dl
–Cluster properties can indeed “hamper” the
CMBR
–The CMBR is heated by the ICM, altering the frequency: Δν/ν = 4kTe/mec2,
leading to:
–ΔT/T = - ∫ 2kTe/mec2 dτT (hν << kTe)
–At low frequencies, REDUCES the temperature of the CMBR.
–Can get distance estimates from S-Z effect.