Related papers: Two-photon annihilation into pion pairs
We investigate a method to produce photon pairs by four-wave mixing in photonic crystal fibers (PCFs). By controlling the wavelength of the pump light, which determines the phase matching condition for four-wave mixing, we can obtain a…
Starting from a bound-state model of weakly bound quarks for ($q \bar{q}$) mesons, we derive a formalism for computing the production or decay of such mesons, whatever the value of their internal orbital angular momentum L. That approach…
Quantum entanglement in high-energy collisions is often obscured by finite lifetimes, dynamical evolution, and final-state interactions, complicating the identification of genuinely quantum correlations. Ultra-peripheral heavy-ion…
We propose a new method for generating photon pairs from coherent light using polarization-dependent two-photon absorption. We study the photon statistics of two orthogonally polarized modes by solving a master equation, and show that when…
A simple model of a composite nucleon is developed in which a fermion and a boson, representing quark and diquark constituents of the nucleon, form a bound state owing to a contact interaction. Photon and pion couplings to the quark provide…
Two photon collisions offer a variety of physics studies that can be performed at the future electron-positron colliders. Using the planned CEPC parameters as a benchmark we consider several topics to be studied in the two-photon…
Two-photon emission of an electron in an electromagnetic plane wave of vanishing frequency is calculated. The unpolarised probability is split into a two-step process, which is shown to be exactly equal to an integration over polarised…
We study the hard exclusive production of two pions in the virtual photon fragmentation region with various invariant masses including the resonance region. The amplitude is expressed in terms of two-pion light cone distribution amplitudes…
We calculated the production of the Higgs boson (H) by two-photon interaction with the equivalent photon approximation in nucleus-nucleus collision, proton-nucleus collision, and proton-proton collision. The numerical results show that the…
The cross section for exclusive production of $\pi^+ \pi^-$ and $\pi^0 \pi^0$ meson pairs in ultrarelativistic heavy ion collisions is calculated for LHC energy $\sqrt{s_{NN}} =$ 3.5 TeV taking into account photon-photon mechanism. We…
We study exclusive $\pi^+ \pi^-$ pair production near $\rho^0$ resonance peak in ultraperipheral heavy ion collisions. Pion pair can either be produced via two photon fusion process or from the decay of $\rho^0$ in photon-nuclear reaction.…
The production of hard photons and neutral pions in 190 MeV proton induced reactions on C, Ca, Ni, and W targets has been for the first time concurrently studied. Angular distributions and energy spectra up to the kinematical limit are…
We show that exclusive production of a pair of high transverse momentum photons in pion-nucleon collisions can be systematically studied in QCD factorization approach if the photon's transverse momentum $q_T$ with respect to the colliding…
This work extends our previous studies of two-photon annihilation into baryon-antibaryon pairs from spin-1/2 octet to spin-3/2 decuplet baryons. Our approach is based on perturbative QCD and treats baryons as quark-diquark systems. Using…
We explore the photoproduction mechanisms for charged and neutral pion pairs off a heavy nucleus at threshold. We calculate the production of charged pairs in the Coulomb field of the nucleus in the Born approximation using explicit…
In this paper, we have given the spin states of two-photon, which are expressed by the quadratic combination of two single photon spin states, they are a kind of quantum expression. Otherwise, we give all entanglement states of two-photon,…
We isolate the two-step mechanism involving a real intermediate photon from the one-step mechanism involving a virtual photon for the trident process in a constant crossed field. The two-step process is shown to agree with an integration…
In an intense laser field, an electron may decay by emitting a pair of photons. The two photons emitted during the process, which can be interpreted as a laser-dressed double Compton scattering, remain entangled in a quantifiable way:…
We derive the pair-production probability in a constant electric field in Rindler coordinates in a quasi-classical approximation. Our result is different from the pair-production probability in an inertial frame (Schwinger formula). In…
This review covers selected results from the LEP experiments on the structure of quasi-real and virtual photons. The topics discussed are the total hadronic cross-section for photon-photon scattering, hadron production, jet cross-sections,…