2011/09/01 by Bastian B. Brandt, Brandt, Bastian B., Andreas Juttner +3
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Phenomenology (hep-ph) #Nuclear Theory (nucl-th) #hep-lat #hep-ph #nucl-th
paper · pdf · doi:10.48550/arxiv.1109.0196
4 pages, 4 figures, talk presented at Hadron 2011: 14th International Conference on Hadron Spectroscopy, Munich, Germany
arxiv created 2011/09/01 · arxiv updated 2011/09/02
We present a lattice calculation of the vector form factor of the pion for two flavours of non-perturbatively O(a) improved Wilson fermions. For the measurements we utilise the CLS ensembles which include various lattice spacings and pion masses down to about 250 MeV. To obtain a fine momentum resolution near zero momentum transfer (q2) partially twisted boundary conditions are employed using several twist angles. Due to the fine resolution around q2=0 we are able to determine the slope of the form factor and, in turn, extract the charge radius of the pion without any model dependence. The results for the form factor and the charge radius are then compared to chiral perturbation theory and phenomenological models which are used to extrapolate the results to the physical point.