相关论文: Diphoton Generalized Distribution Amplitudes
Propagation of gamma-beam in the anisotropic medium is considered. The simpliest example of such a medium of the general type is a combination of the two linearly polarized monochromatic laser waves with different frequencies (dichromatic…
Generalized distribution amplitudes (GDAs) are one type of three-dimensional structure functions, and they are related to the generalized distribution functions (GPDs) by the $s$-$t$ crossing of the Mandelstam variables. The GDA studies…
In this paper, we discuss computational aspects to obtain accurate inferences for the parameters of the generalized gamma (GG) distribution. Usually, the solution of the maximum likelihood estimators (MLE) for the GG distribution have no…
Quantum simulation of quantum field theories offers a new way to investigate properties of the fundamental constituents of matter. We develop quantum simulation algorithms based on the light-front formulation of relativistic field theories.…
The photon energy spectrum in inclusive weak radiative B -> X_s gamma decay is computed to order alpha_s^2 beta_0. This result is used to extract a value for the HQET parameter $\bar\Lambda$ from the average <1-2E_\gamma/m_B>, and a value…
An approach is proposed to calculate Generalized Parton Distributions (GPDs) in a Constituent Quark Model (CQM) scenario. These off-diagonal distributions are obtained from momentum space wave functions to be evaluated in a given non…
We present a novel approach to compute Generalized Parton Distributions within the Lightfront Wave Function overlap framework. We show how to systematically extend Generalized Parton Distributions computed within the DGLAP region to the…
The ratio of the cross sections for the transversely and longitudinally virtual photon polarizations, $\sigma^{\gamma^{*}p}_{L/T}$, at high photon-hadron energy scattering is studied. I investigate the relationship between the gluon…
We compute the exclusive photoproduction of a $\gamma\,\pi^\pm$ pair using the collinear factorisation framework, in the kinematic regime where the pair has a large invariant mass. This exclusive channel presents a new avenue for the…
The quark generalised parton distributions of the pion are calculated from lightcone wavefunctions in transverse lattice gauge theory at large N_c. The pion effective size is found to decrease with increasing momentum transfer. An analytic…
Generalized parton distributions (GPDs) have been investigated in the deeply virtual Compton scattering (DVCS) to solve the proton spin puzzle. On the other hand, the generalized distribution amplitudes (GDAs) can be studied in the…
We study the diffractive production of photons in gamma-p and gamma-gamma collisions. We specifically compute the rates for gamma*-p -> gamma-X and for gamma*-gamma* -> gamma-gamma, where X denotes the proton dissociation. We focus on the…
A method to derive the convenient representations for many two-photon amplitudes is suggested. It is based on the use of the gauge in which the photon propagator has only space components. The amplitudes obtained have no any strong…
A generic model for alternating lags in QPO harmonics is presented where variations in the photon spectrum are caused by oscillations in two parameters that characterize the spectrum. It is further assumed that variations in one of the…
We derive the Leading Order DGLAP evolution of gluon distribution function in the target light cone gauge starting from its standard operator definition. The derivation is performed using the background field formalism also employed in the…
A better understanding of the optical properties of random photonic structures is beneficial for many applications, such as random lasing, optical imaging and photovoltaics. Here we investigated the light transmission properties of…
The concepts of Generalized Parton Distributions (GPD) are reviewed in an introductory and phenomenological fashion. These distributions provide a rich and unifying picture of the nucleon structure. Their physical meaning is discussed. The…
We propose a new complete method, based on the Wigner distributions of photons, how to calculate differential distributions of dileptons created via photon-photon fusion in semicentral ($b<2R_A$) $AA$ collisions. The formalism is used to…
We investigate through a Generalized Langevin formalism the phenomenon of anomalous diffusion for asymptotic times, and we generalized the concept of the diffusion exponent. A method is proposed to obtain the diffusion coefficient…
The molecular motion in heterogeneous media displays anomalous diffusion by the mean-squared displacement $\langle X^2(t) \rangle = 2 D t^\alpha$. Motivated by experiments reporting populations of the anomalous diffusion parameters $\alpha$…