Problems in Neutrino-Nucleus Scattering
G. T. Garvey
LANL
Recently published differential cross sections for
neutrino+12C charged current quasi-elasttic scattering (CCQE) by the MiniBooNE
collaboration are ~40% larger than typical impulse approximation calculations of CCQE.
Some of the difference is due to poor communication betwen the theoriats and
experimentalists as to what constitutes CCQE scattering. More fundamntally the observed
cross section appears to be larger than the CCQE on 6 free neutrons. A prominent
theorist in the field claims "a new paradigm ... will be required." There have been
several recent publications failing to account for the observed cross sections. In order to
proceed with analysis of their data in the search for nm*ne oscillation the MiniBooNE
collaboration fit the neutrino+12C CCQE yield by using MA=1.35 GeV for the nucleon axial
form factor. The world average for MA is 1.02 +/- 0.02 GeV. There exists an RPA
calculation that finds good agreement with the measured yield but does no reproduce the
measured angular distribution. Earler work on electron quasi-elastic scattering
demonstrated that short-range correlations plus two-body currents grealtly enhanced the
nuclear transverse vector response in agreement with expriment. Extending this
approach to neutrino CCQE appears attractive. The current state of affairs in this active
area will be presented, noting improvements needed in theory and experiment for neutrino-
nucleus scattering in the range of 0.3