اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدBBGKY kinetic approach for an e-e+gamma plasma created from the vacuum in a strong laser-generated electric field: The one-photon annihilation channel
113
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
In the present work a closed system of kinetic equations is obtained from the truncation of the BBGKY hierarchy for the description of the vacuum creation of an electron - positron plasma and secondary photons due to a strong laser field. This truncation is performed in the Markovian approximation for the one-photon annihilation channel which is accessible due to the presence of the strong external field. Estimates of the photon production rate are obtained for different domains of laser field parameters (frequency nu and field strength E). A huge quantity of optical photons of the quasiclassical laser field is necessary to satisfy the conservation laws of energy and momentum of the constituents (e-, e+, gamma) in this channel. Since the number of these optical photons corresponds to the order of perturbation theory, a vanishingly small photon production rate results for the optical region and strongly subcritical fields E << E_c. In the gamma-ray region nu <~ m the required number of laser photons is small and the production rate of photons from the one-photon annihilation process becomes accessible to observations for subcritical fields E <~ E_c. In the infrared region the photon distribution has a 1/k spectrum typical for flicker noise.
قيم البحث
اقرأ أيضاً
It is well known that in the presence of strong external electromagnetic fields many processes forbidden in standard QED become possible. One example is the one-photon annihilation process considered recently by the present authors in the framework o
f a kinetic approach to the quasiparticle e-e+ gamma plasma created from vacuum in the focal spot of two counter-propagating laser beams. In these works the domain of large values of the adiabaticity parameter gamma >> 1 (corresponding to multiphoton processes) was considered. In the present work we estimate the intensity of the radiation stemming from photon annihilation in the framework of the effective mass model where gamma < 1, corresponding to large electric fields E < E_c=m^2/e and high laser field frequencies (the domain characteristic for X-ray lasers of the next generation). Under such limiting conditions the resulting effect is sufficiently large to be accessible to experimental observation.
In the present work a closed system of kinetic equations is obtained for the description of the vacuum creation of an electron - positron plasma and secondary photons due to a strong laser field. An estimate for the photon energy distribution is obta
ined. In the Markovian approximation the photon distribution has a 1/k spectrum (flicker noise).
We consider vacuum polarization effects in the one-photon annihilation channel within a kinetic description of the e+ e- plasma produced from the vacuum in the focal spot of counter-propagating laser beams. This entails essential changes in the struc
ture of the photon kinetic equation. We investigate the domain of large adiabaticity parameters gamma >> 1 where the photon radiation turns out to be very small. A more thorough examination of the domain gamma < 1 needs separate investigation. However, an exploratory study has shown that the one-photon annihilation channel can lead for some domains of laser field parameters (e.g., for the XFEL) to contributions accessible for observation.
The process of electron-positron pair production by a photon with subsequent annihilation to a single photon in a strong magnetic field has been studied. The general amplitude has been calculated and the process rate have been found in the low Landau
levels approximation (resonant and nonresonant cases). The comparison of resonant and nonresonant cases shows a significant excess of the resonant rate. The polarization of the final photon in a strong magnetic field has also been found. It has been shown that polarizations of the initial and the final photons are independent except for the case of normal linear polarization of the initial photon.
If the $X(3872)$ is a weakly bound charm-meson molecule, it can be produced in $e^+ e^-$ annihilation by the creation of $D^{*0} bar D^{*0}$ from a virtual photon followed by the rescattering of the P-wave charm-meson pair into the $X$ and a photon.
A triangle singularity produces a narrow peak in the cross section for $e^+ e^- to X gamma$ 2.2 MeV above the $D^{*0} bar{D}^{*0}$ threshold. We predict the normalized cross section in the region of the peak. We show that the absorptive contribution to the cross section for $e^+ e^- to D^{*0} bar D^{*0} to X gamma$, which was calculated previously by Dubynskiy and Voloshin, does not give a good approximation to the peak from the triangle singularity.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
