33 research outputs found
Photon splitting above the pair creation threshold in a strong magnetic field
The process of photon splitting in a strong
magnetic field is investigated both below and above the pair creation
threshold. Contrary to the statement by Baier et al., the ``allowed'' channel
\alw is shown not to be a comprehensive description of splitting in the
strong field because the ``forbidden'' channel \frb is also essential. The
partial amplitudes and the splitting probabilities are calculated taking
account of the photon dispersion and large radiative corrections near the
resonance.Comment: 13 pages, 3 figures, LaTeX, uses epsf.sty, numerical error in eq.(11)
corrected, typos fixed, presentation improved, accepted to Physics Letters
The influence of strong magnetic field on photon-neutrino reactions
The two-photon two-neutrino interaction induced by magnetic field is
investigated. In particular the processes and
are studied in the presence of strong magnetic
field. An effective Lagrangian and partial amplitudes of the processes are
presented. Neutrino emissivities due to the reactions and are calculated taking into
account of the photon dispersion and large radiative corrections. A comparison
of the results obtained with previous estimations and another inducing
mechanisms of the processes under consideration is made.Comment: 16 pages, LATEX, 3 EPS figures, based on the talk presented at XXXI
ITEP Winter School of Physics, Moscow, Russia, February 18 - 26, 200
Matter-induced vertices for photon splitting in a weakly magnetized plasma
We evaluate the three-photon vertex functions at order and in a
weak constant magnetic field at finite temperature and density with on shell
external lines. Their application to the study of the photon splitting process
leads to consider high energy photons whose dispersion relations are not
changed significantly by the plasma effects. The absorption coefficient is
computed and compared with the perturbative vacuum result. For the values of
temperature and density of some astrophysical objects with a weak magnetic
field, the matter effects are negligible.Comment: 14 pages, 1 figure. Accepted for publication in PR
Formation of "Lightnings" in a Neutron Star Magnetosphere and the Nature of RRATs
The connection between the radio emission from "lightnings" produced by the
absorption of high-energy photons from the cosmic gamma-ray background in a
neutron star magnetosphere and radio bursts from rotating radio transients
(RRATs) is investigated. The lightning length reaches 1000 km; the lightning
radius is 100 m and is comparable to the polar cap radius. If a closed
magnetosphere is filled with a dense plasma, then lightnings are efficiently
formed only in the region of open magnetic field lines. For the radio emission
from a separate lightning to be observed, the polar cap of the neutron star
must be directed toward the observer and, at the same time, the lightning must
be formed. The maximum burst rate is related to the time of the plasma outflow
from the polar cap region. The typical interval between two consecutive bursts
is ~100 s. The width of a single radio burst can be determined both by the
width of the emission cone formed by the lightning emitting regions at some
height above the neutron star surface and by a finite lightning lifetime. The
width of the phase distribution for radio bursts from RRATs, along with the
integrated pulse width, is determined by the width of the bundle of open
magnetic field lines at the formation height of the radio emission. The results
obtained are consistent with the currently available data and are indicative of
a close connection between RRATs, intermittent pulsars, and extreme nullers.Comment: 24 pages, no figures, references update
Photon splitting in a strongly magnetized, charge-asymmetric plasma
The process of the photon splitting, γ → γγ, is investigated in the presence of strongly magnetized charge-asymmetric cold plasma. The dispersion properties of photons and the new polarization selection rules are obtained in such plasma. The absorption rate of the leading photon splitting channel are calculated with taking account of the photon dispersion and wave function renormalization. In addition, a comparison of the photon splitting and the Compton scattering processes is performed
Photon splitting in a strongly magnetized, charge-asymmetric plasma
The process of the photon splitting, γ → γγ, is investigated in the presence of strongly magnetized charge-asymmetric cold plasma. The dispersion properties of photons and the new polarization selection rules are obtained in such plasma. The absorption rate of the leading photon splitting channel are calculated with taking account of the photon dispersion and wave function renormalization. In addition, a comparison of the photon splitting and the Compton scattering processes is performed
Photon splitting in strongly magnetized medium with taking into account positronium influence
The process of the photon splitting, γ → γγ, is investigated in strongly magnetized vacuum with taking into account positronium influence. The dispersion properties of photons and the new polarization selection rules are obtained. The absorption rate of the leading photon splitting channels are calculated with taking account of the photon dispersion and wave function renormalization
Photon splitting in strongly magnetized medium with taking into account positronium influence
The process of the photon splitting, γ → γγ, is investigated in strongly magnetized vacuum with taking into account positronium influence. The dispersion properties of photons and the new polarization selection rules are obtained. The absorption rate of the leading photon splitting channels are calculated with taking account of the photon dispersion and wave function renormalization