The Sunyaev-Zeldovich effect reference article from the English Wikipedia on 24-Apr-2004
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Sunyaev-Zeldovich effect

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The Sunyaev-Zeldovich effect (SZ effect or Sunyaev-Zeldovich theory) is due to high energy electrons distorting thecosmic microwave background radiation (CMB) through the inverse Compton effect, in which some of the high energy of the electrons is transferred to the low energy photons. This Compton effect between the photons and electrons alters the CMB spectrum observed, though current detectors are not sensitive enough for the small scale SZ effect.

High energy of the negative particles cause photons to receive energy. The background radiation's isotropy, such that of a plasma state in all directions, increases this induction. The plasmas of galaxies scatters the cosmic background radiation and relatively distort the background spectrum, thus contributing to statistical uncertainties. This Compton effect between the photons and electrons alters the CMB spectrum observed. When investigated, the Compton effect between the "photons" and the "electrons" alters the spectrum observed by the detectors, though the detectors are not sensitive enough for the small scale SZ effect.

The Sunyaev-Zeldovich theory relies on:

Sunyaev and Zeldovich predicted the effect, and conducted research in 1969, 1972, and 1980. The Sunyaev-Zeldovich effect is of major astrophysical and cosmological interest. It determines disk accretion and photon-electron scattering. It can also help determine the value of the Hubble constant and universal motion parameters.

Observed distortions of the microwave background spectrum are used to detect the of density perturbations of the universe. Using the Sunyaev-Zeldovich theory, research on very large scale velocity fields has been carried out, and future CMB detection experiments will have to account for the contributions from various mediums generated through the effect. Current research is focused on the distinctive type of angular fluctuations from the effect in the microwave background, due to plasma galaxy clusters redshifts, to measure the scale of the universe. Hydrodynamic structure formation experiments are being studied to gain data on thermal and kinetic effects in the theory. Observations are difficult due to the size of the effect and other discrete electromagnetic fluctuations.


See also: 
Background radiation,
Compton effect,
Cosmic background radiation,
Cosmic microwave background radiation,
Non-standard cosmology,
Quasar, Redshifts and Controversies,
Rashid Sunyaev

External links and references