Scattering and Reactions of Intermediate Energy Projectiles

This grant will support the experimental work of the

Intermediate Energy Nuclear Physics Group at Rutgers University.

The Rutgers group carries out experiments primarily

at the continuous electron beam accelerator, CEBAF, located at the

Thomas Jefferson National Accelerator Facility

in Newport News, Virginia. Their experiments are aimed at

improving our understanding of the structure of nucleons. Although

we know the basic building blocks of nucleons are quarks and gluons,

how they interact to give the nucleon its observed properties is

still not well known. Our experiments use spin, a fundamental property

of sub-atomic particles, as a sensitive probe of the

nucleon. One type of experiment measures the polarization of

ejected protons when polarized (spin-aligned) electrons are scattered

from nucleons. This determines the distributions of charge and

magnetization in the proton, and how those distributions are changed

when the proton is bound in a nucleus. Another type of experiments

uses polarized photons absorbed on deuterium. The polarization of

the outgoing protons is sensitive to the mechanism of the absorption,

and hence to the way the quarks and gluons interact in the deuteron.

The third major type of experiments use electrons scattered from a

polarized helium target to study the quark spin structure of the neutron.