HYPERgeometric functions DIfferential REduction: MATHEMATICA based packages for differential reduction of generalized hypergeometric functions: Horn hypergeometric functions of two variables

HYPERDIRE is a project devoted to the creation of a set of Mathematica-based programs for the differential reduction of hypergeometric functions. The current version allows for manipulations involving the full set of Horn-type hypergeometric functions of two variables, including 30 functions.Comment: minor corrections, publushed versio

Derivatives of Horn-type hypergeometric functions with respect to their parameters

We consider the derivatives of Horn hypergeometric functions of any number variables with respect to their parameters. The derivative of the function in $n$ variables is expressed as a Horn hypergeometric series of $n+1$ infinite summations depending on the same variables and with the same region of convergence as for original Horn function. The derivatives of Appell functions, generalized hypergeometric functions, confluent and non-confluent Lauricella series and generalized Lauricella series are explicitly presented. Applications to the calculation of Feynman diagrams are discussed, especially the series expansion in $\epsilon$ within dimensional regularization. Connections with other classes of special functions are discussed as well.Comment: 27 page

A distribution of the temperature in a ring of the incompressible, viscous liquid with two free boundaries. Exact solutions

It has been found the exact solutions for nonstationary distribution of the temperature in the liquid ring with two viscosities and two free boundaries of the ring

On the measurement of χ2(3P2)\chi_2(^3P_2) quarkonium state in the processes e++e−→pˉ+pe^++e^-\to \bar p+p and pˉ+p→e++e−\bar p+p\to e^++e^-

The intermediate quarkonium state $\chi_2(^3P_2)$ in electron-positron annihilation to proton and antiproton as well as in antiproton-proton annihilation to electron and positron can produce backward-forward asymmetry, when populated through two photon exchange. We use the dispersion relation method, which permits to express the asymmetry in terms of partial widths of quarkonium decay. The asymmetry dependence on the center of mass energy in the range near the resonance is presented. The comparison with a similar effect in these reactions with the neutral $Z$-boson in the intermediate state is given. We show that these effects are $\le 10^{-3}$. The main source of asymmetry is of pure QED origin ($\sim 10^{-2}$) which arises from the interference between initial and final state real photon emission