Spin-polarization effects in the processes of synchrotron radiation and electron-positron pair production by a photon in a magnetic field

Abstract

Spin and polarization effects and correlations between them in the processes of pair production by a photon and synchrotron radiation in a magnetic field are considered. Expressions for the probabilities of the processes with arbitrary polarizations of the particles are obtained. These expressions are analyzed in detail in both the Lowest Landau Levels and ultrarelativistic approximations. PACS numbers: 12.20.-mQuantum electrodynamics , 13.88.+ePolarization in interactions and scattering

Pair production in a magnetic and radiation field in a pulsar magnetosphere

“…Let us analyze Eqs. (17)- (19). When the pair is produced in the energetically low spin state (µ e = −1, µ p = 1) the process has the greatest rate because the corresponding expression (18) contains the small parameter b in the lowest power.…”

“…After carrying out corresponding calculations, the process rate with arbitrary spin projections takes the form [19]:…”

Electron-positron pair production by an electron in a magnetic field near the process threshold

“…To estimate the emission probability, it is necessary to use the ultrarelativistic approximation [7,14]. Choosing the initial electron energy to be 3m, we will obtain an estimate of the total synchrotron emission probability: However, this includes the processes of photon emission with an energy insufficient for pair production.…”

“…First of all, note that the total probability contains no singularities, when the longitudinal particle momenta are zero, characteristic of the photoproduction process γ → ee + [12][13][14]. From Eqs.…”

“…The magnetic field is h = 0.1 (≈ 4.4 · 10 12 G). For the photoproduction probability, we use an expression derived in the ultraquantum approximation [14,17]. Let us take the initial photon frequency to be ω = 2m, the electron and positron level numbers to be l f = 0, and the magnetic field to be h = 0.1.…”