Polarized triplet production by circularly polarized photons

A process of the pair production by a circularly polarized photon in the field of unpolarized atomic electron has been considered in the Weizaecker-Williams approximation. The degree of longitudinal polarization of positron and electron has been calculated. An exclusive cross-section as well as a spectral distribution are obtained. We estimate the accuracy of our calculations at the level of a few percent. We show the identity of the positron polarization for considered process and for process of pair production in the screened Coulomb field of nucleus.Comment: 9 pages, 3 picture

Mjerenje linearne polarizacije realnih fotona

A survey of known methods of analyzing linear polarization of high-energy photons is presented. The methods of pair photoproduction in single crystals and in amorphous targets are briefly discussed. The method of measurement of photon linear polarization using azimuthal asymmetry of the recoil electrons from pair photoproduction on electron (triplet photoproduction process) is considered in details. The optimum region of kinematic parameters of emitted particles in which analyzing power increases is discussed. Possibility of using CLAS for the measurement of linear photon polarization by analyzing the recoil-electron distribution in triplet photoproduction process (when shielding magnet is turned off) is considered.Daje se pregled poznatih metoda za određivanje linearne polarizacije visokoenergijskih fotona. Raspravlja se kratko tvorba parova u monokristalima i amorfnim metama. Podrobno se razmatra metoda mjerenja polarizacije određivanjem azimutalne asimetrije elektrona od fototvorbe na elektronima (trojna fototvorba). Raspravlja se najpovoljnije područje kinematičkih parametara izlaznih čestica. Izlaže se mogćcnost primjene CLASa za određivanje linearne polarizacije fotona mjerenjem raspodjele odbijenih elektrona iz trojnog fototvorbenog procesa (za vrijeme mjerenja CLASov magnet bi se isključio)

Mjerenje linearne polarizacije realnih fotona

A survey of known methods of analyzing linear polarization of high-energy photons is presented. The methods of pair photoproduction in single crystals and in amorphous targets are briefly discussed. The method of measurement of photon linear polarization using azimuthal asymmetry of the recoil electrons from pair photoproduction on electron (triplet photoproduction process) is considered in details. The optimum region of kinematic parameters of emitted particles in which analyzing power increases is discussed. Possibility of using CLAS for the measurement of linear photon polarization by analyzing the recoil-electron distribution in triplet photoproduction process (when shielding magnet is turned off) is considered.Daje se pregled poznatih metoda za određivanje linearne polarizacije visokoenergijskih fotona. Raspravlja se kratko tvorba parova u monokristalima i amorfnim metama. Podrobno se razmatra metoda mjerenja polarizacije određivanjem azimutalne asimetrije elektrona od fototvorbe na elektronima (trojna fototvorba). Raspravlja se najpovoljnije područje kinematičkih parametara izlaznih čestica. Izlaže se mogćcnost primjene CLASa za određivanje linearne polarizacije fotona mjerenjem raspodjele odbijenih elektrona iz trojnog fototvorbenog procesa (za vrijeme mjerenja CLASov magnet bi se isključio)

Bremsstrahlung photon polarization for ee±→(eγ)e±ee^\pm\to (e\gamma)e^\pm, and ep→(eγ)pep\to (e\gamma)p high energy collisions

The polarization of bremsstrahlung photon in the processes $ee^\pm\to (e\gamma)e^\pm$, and $ep\to (e\gamma)p$ is calculated for peripheral kinematics, in the high energy limit where the cross section does not decrease with the incident energy. When the initial electron is unpolarized(longitudinally polarized) the final photon can be linearly (circularly) polarized. The Stokes parameters of the photon polarization are calculated as a function of the kinematical variables of process: the energy of recoil particle, the energy fraction of scattered electron, and the polar and azimuthal angles of photon. Numerical results are given in form of tables, for typical values of the relevant kinematic variables.Comment: 9 pages, 3 figure