Dynamics Of Hadronization From Nuclear Semi Inclusive Deep Inelastic Scattering.pdfVIP

Dynamics of Hadronization from Nuclear Semi Inclusive Deep Inelastic Scattering Kawtar Hafidi – on behalf of the CLAS collaboration Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA The CLAS experiment E02-104, part of the EG2 run at Jefferson Lab, was performed to study the hadronization process using semi inclusive deep inelastic scattering off nuclei. Electron beam energy of 5 GeV and the CLAS large acceptance detector were used to study charged pion production. The high luminosity available at Jefferson Lab and the CLAS large acceptance are key factors for such measurements allowing high statistics and therefore multidimensional analyses of the data. Both the multiplicity ratio and the transverse momentum broadening for carbon, iron and lead relative to deuterium are measured. Preliminary results for positive pions are discussed. Keywords: Hadronization, nuclear attenuation, transverse momentum broadening PACS: 13.87.Fh, 13.60.-r, 14.20.-c, 14.40.-n Introduction Hadronization is the mechanism by which the quark, when ejected from a nucleon neutralizes its color to from many hadrons in the final state. The description of hadronization in terms of fragmentation functions is known in the vacuum, but the physical information on its dynamics is still a mystery. The time-space evolution of the hadron formation is unknown due to the fact that it is a non perturbatif process and therefore is hard to calculate at the most fundamental level. Unfortunately, Lattice QCD calculations are not yet helpful in this matter. To access this dynamic, the nucleus will play the role of the detector since the production length is comparable with the nuclear size. The nuclear environment provides a un