Deeply virtual vector meson electroproduction at small Bjorken-x

It is reported on an analysis of vector meson electroproduction at small Bjorken-x within the handbag approach. Using a model for the generalized parton distribution and calculating the partonic subprocess, electroproduction off gluons, within the modified perturbative approach, cross sections and spin density matrix elements are evaluated. The numerical results agree fairly well with recent HERA data.Comment: 4 pages, 4 figures, contribution to DIS05, Madison, US

Transversity in exclusive electroproduction of pseudoscalar mesons

In this talk it is reported on an analysis of hard exclusive electroproduction of pseudoscalar mesons within the handbag approach. It is argued that recent measurements of pion electroproduction performed by HERMES and CLAS clearly indicate the occurence of strong contributions from transversely polarized photons. Within the handbag approach such transitions are described by the transversity GPDs accompanied by twist-3 pion wave functions. It is shown that this handbag approach leads to results on cross sections and single-spin asymmetries in fair agreement with experiment. The surprising result is that the pi0 cross section is dominated by gamma_T -> pion transitions. Predictions for other pseudoscalar meson channels are also discussed.Comment: 6 pages, 8 figures, using PoS.cls talk presented at QNP2012, Paris (2012

Fully Realizing Partial Realization

There has been a movement in philosophy, growing over the last twenty years, to treat dispositionality as irreducible and, in turn, offer dispositional accounts of important metaphysical matters such as the laws of nature, free will, causation, and modality. However, unlike the earlier turn towards possible worlds in metaphysics, the turn towards dispositions hasn’t had much impact in semantics. But this is, in my view, largely because semanticists have yet to consider what dispositional analyses of (say) tense, aspect, generics, or modals would look like. My aim in this paper is to push the dispositionality movement forward on the semantics front by considering a dispositional analysis of the progressive aspect