Conference paper
New results on perturbative colour transparency in quasi-exclusive electroproduction
Pankaj Jain
; Physics Department, I.I.T. Kanpur, 208016, India
Bijoy Kundu
; Physics Department, I.I.T. Kanpur, 208016, India
John Ralston
; Department of Physics & Astronomy, University of Kansas, Lawrence, KS 66045, U.S.A.
Jim Samuelsson
; Physics Department, I.I.T. Kanpur, 208016, India
Abstract
We review the perturbative QCD formalism of hadronic electromagnetic form factors and the colour transparency ratio for quasi-exclusive electroproduction of the proton and pion from nuclear targets. We have completed the first full calculations including all leading-order quark subprocesses and integrations over distribution amplitudes, including Sudakov effects. For the case of the proton, the calculated result shows scaling beyond Q2 = 10 GeV2. The calculation incorporating filtering due to the nuclear medium is cleaner than the corresponding calculation in free space because of attenuation of large distance amplitudes. We find that the colour transparency ratio is rather insensitive to theoretical uncertainties inherent in the perturbative formalism, such as the choice of the hadron distribution amplitude.
Keywords
proton and pion quasi-exclusive electroproduction; nuclear targets; perturbative QCD formalism; hadronic electromagnetic form factors; colour transparency ratio
Hrčak ID:
305359
URI
Publication date:
1.6.1999.
Visits: 397 *