Electron-positron annihilation above charm threshold

ELECTRON - POSITRON ANNIHILATION ABOVE 2 GeV AND THE NEW PARTICIZS

New states above charm threshold

In the short time since the Belle Collaboration reported sighting the “missing” charmonium state η c(2 S0) in exclusive B → KKSK π decays [1], new states associated with charmonium have appeared in great profusion. Apart from the long-sought hc(1 P1), recently observed by the CLEO Collaboration in the decay ψ(2S) → πhc → (γγ)(γηc) [2, 3], all the newly observed states lie near or above charm th...

Interference fragmentation functions in electron-positron annihilation

We study the process of electron-positron annihilation into back-to-back jets, where in each jet a pair of hadrons is detected. The orientation of these two pairs with respect to each other can be used to extract the interference fragmentation functions in a clean way, for instance from BELLE or BABAR experiment data. This is of relevance for studies of the transversity distribution function. I...

Positron Annihilation Studies of f-Electron Compounds

We present a theoretical analysis of positron annihilation studies of two isostructural f -electron compounds CeIn3 and UGa3. The interpretation of twodimensional angular correlation of annihilation radiation experiment (2D-ACAR) is based on a parameter-free density functional theory calculations. Our analyses show, that the f -electrons in CeIn3 behave as well localized while in UGa3 it was th...

Semiexclusive production in electron-positron annihilation.

We present a thorough analysis of the direct semiexclusive production in quantum chromodynamics (QCD) of single, highly isolated mesons from electron-positron or two-photon initial states. Corrections of higher order and of subleading twist are considered, and potential divergences in the naive calculation are contained. Monte Carlo methods are used to relate the QCD calculations to experimenta...