相关论文: Photon splitting above the pair creation threshold…
The Breit-Wheeler pair production process in $2+1$ dimensional spacetime is investigated. In the perturbative regime, non-vanishing rates at the energy threshold are found when odd numbers of photons take part on the reaction. This…
We analyze atomic photoexcitation into the discrete states by twisted photons, or photons carrying extra orbital angular momentum along their direction of propagation. From the angular momentum and parity considerations, we are able to…
We examine angular distribution of the probability of correlated fluorescence photon emission from a linear chain of identical equidistant two-level atoms. We selectively excite one of the atoms by a resonant laser field. The atoms are…
Precise total cross-sections and invariant-mass distributions have been measured for photoproduction of pion pairs off the proton producing $p\pi^0\pi^0$ and $n\pi^+\pi^0$ final states from the threshold region up to 800 MeV incident photon…
The recent association of soft gamma repeaters (SGRs) with counterparts in other wavebands has sparked much interest in these sources. One of the recent models for these objects is that they originate in the environs of neutron stars with…
The probability-generating function of the number of electron-positron pairs produced in a uniform electric field is constructed. The mean and variance of the numbers of pairs are calculated, and analytical expressions for the probability…
Magnetic monopoles, if they exist, would be produced amply in strong magnetic fields and high temperatures via the thermal Schwinger process. Such circumstances arise in heavy ion collisions and in neutron stars, both of which imply lower…
Two-photon transitions between atomic states of total electronic angular momentum $J_a=0$ and $J_b=1$ are forbidden when the photons are of the same energy. This selection rule is analogous to the Landau-Yang theorem in particle physics…
Postselection is a non-deterministic mechanism to entangle subsystems, often used in weakly-excited systems. We here show how highly-excited ensembles of two-level emitters can be entangled by photon detection. A collective spin is formed,…
The process of electron positron pair annihilation, driven by strong fields (Inverse Schwinger mechanism) and high-frequency waves, is studied using the Dirac Heisenberg Wigner formalism. In an electron positron plasma, the presence of a…
In this work I studied the production of particles (electron-positron pairs and photons) in the presence of overcritic ($\gg 4.4\cdot 10^{13} \text{gauss}$) slowly varying magnetic fields. The calculations are performed in the framework of…
We present an exploratory study of two pion photo-- and electroproduction off the nucleon in the threshold region. To calculate the pertinent amplitudes, we make use of heavy baryon chiral perturbation theory. We show that due to finite…
The emissivity for the neutrino pair synchrotron radiation in strong magnetic fields has been calculated both analytically and numerically for high densities and moderate temperatures, as can be found in neutron stars. Under these…
A double-slit experiment with entangled photons is theoretically analyzed. It is shown that, under suitable conditions, two entangled photons of wavelength $\lambda$ can behave like a \emph{biphoton} of wavelength $\lambda/2$. The…
The paper is withdrawn and will be replaced at a later time by a significantly revised and extended version.
Ultraperipheral heavy-ion collisions (UPCs) offer unique opportunities to study processes under strong electromagnetic fields. In these collisions, highly charged fast-moving ions carry strong electromagnetic fields that can be effectively…
It is shown that in strongly magnetized neutron stars, there exist upper limits of magnetic field strength, beyond which the self energies for both neutron and proton components of neutron star matter become complex in nature. As a…
Magnetic fields observed across cosmic scales are difficult to explain within conventional physics. A primordial origin is, thus, often assumed. While a nonminimal coupling of the inflaton with the electromagnetic field could theoretically…
An electron-positron pair ($e^- e^+$) is created in vacuum above a critical electric field strength $E_{crt}$ which is quite large in the laboratory scale. The photon, thus the field, annihilates in the pair creation process. Here, we…
We show that polarized gamma p -> \pi^+ n in the threshold region is an excellent candidate for measuring the leading parity-violating pion-nucleon coupling h_{\pi NN}^{(1)} to an uncertainty of 20% if it has a natural size from dimensional…