Spin Observables in Transition-Distribution-Amplitude Studies

Abstract

Exclusive hadronic reactions with a massive lepton pair (l^+l^-) in the final state will be measured with PANDA at GSI-FAIR and with Compass at CERN, both in p+p-bar -> l^+l^-+pi and pi+N -> N'+l^+l^-. Similarly, electroproduction of a meson in the backward region will be studied at JLAB. We discuss here how the spin structure of the amplitude for such processes will enable us to disentangle various mechanisms. For instance, target-transverse-spin asymmetries are specific of a partonic description, where the amplitude is factorised in terms of baryon to meson or meson to baryon Transition Distribution Amplitudes (TDAs) as opposed to what is expected from baryon-exchange contributions.

Contributed to the 19th International Spin Physics Symposium (SPIN 2010), September 27 - October 2, 2010, Juelich, Germany. 8 pages, 7 figures, uses jpconf.cls, jpconf11.clo, iopams.sty (included)

References in corpus (4)

• Production of a pion in association with a high-Q2 dilepton pair in antiproton-proton annihilation at GSI-FAIR
• Testing axial and electromagnetic nucleon form factors in time-like regions in the processes $\bar{p}+n\to {\pi }^{-}+{\ell }^{-}+{\ell }^{+}$ and $\bar{p}+p\to {\pi }^0+{\ell }^{-}+{\ell }^{+}$, $\ell =e$, $\mu$
• A spectral representation for baryon to meson transition distribution amplitudes
• Backward DVCS and Proton to Photon Transition Distribution Amplitudes

Cited by in corpus (6)

• A consistent model for πN transition distribution amplitudes and backward pion electroproduction
• Hard exclusive pion electroproduction at backward angles with CLAS
• Transition distribution amplitudes and hard exclusive reactions with baryon number transfer
• Revisiting the production of charmonium plus a light meson at PANDA
• Baryon-to-meson transition distribution amplitudes: formalism and models
• Toward an advanced phenomenology of $\pi N$ transition distribution amplitudes