COHERENT BREMSSTRAHLUNG AT B-FACTORIES

Coherent bremsstrahlung (CBS) is a specific type of radiation at colliders with short bunches. In the present paper I calculate the main characteristics of CBS for known projects of B-factories. At these colliders it will be emitted dN(gamma)similar to 10(8)dE(gamma)/E(gamma) photons for a single collision in the energy range E(gamma) less than or similar to 10 keV. It seems that CBS can be a potential tool for optimizing collisions and for measuring beam parameters. Indeed, the bunch length sigma(z) can be found from the CBS spectrum because critical energy E(c) proportional to 1/sigma(z); the horizontal transverse bunch size sigma(x) is related to dN(gamma)proportional to 1/sigma(x)(2). Moreover, CBS may be very useful for a fast control over an impact parameter R between the colliding bunch axes because a dependence of dN(gamma) on R has a very specific behavior.