Measurement of quasi-elastic 12C(p,2p) scattering at high momentum transfer

We measured the high-momentum quasi-elastic 12C(p,2p) reaction (at center of mass angle near 90 degrees) for 6 and 7.5 GeV/c incident protons. The three-momentum components of both final state protons were measured and the missing energy and momentum of the target proton in the nucleus were determined. The validity of the quasi-elastic picture was verified up to Fermi momenta of about 450 MeV/c, where it might be questionable. Transverse and longitudinal Fermi momentum distributions of the target proton were measured and compared to independent particle models which do not reproduce the large momentum tails. We also observed that the transverse Fermi distribution gets wider as the longitudinal component increases in the beam direction, in contrast to a simple Fermi gas model.Comment: 4 pages including 3 figure

Study of a Depolarizing Resonance at the IUCF Cooler Ring

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Microwave-induced control of Free Electron Laser radiation

The dynamical response of a relativistic bunch of electrons injected in a planar magnetic undulator and interacting with a counterpropagating electromagnetic wave is studied. We demonstrate a resonance condition for which the free electron laser (FEL) dynamics is strongly influenced by the presence of the external field. It opens up the possibility of control of short wavelength FEL emission characteristics by changing the parameters of the microwave field without requiring change in the undulator's geometry or configuration. Numerical examples, assuming realistic parameter values analogous to those of the TTF-FEL, currently under development at DESY, are given for possible control of the amplitude or the polarization of the emitted radiation.Comment: 14 pages, 5 figures, accepted for publication in Phys. Rev.

Siberian Snake and Depolarizing Resonance Studies at the Cooler Ring

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Siberian Snake Overcomes "Overlapping" Depolarizing Resonances

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

RF Induced Depolarizing Resonanaces, Spin Flip, and Partial Siberian Snakes

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Possibilities of polarized protons in Sp anti p S and other high energy hadron colliders

The requirements for collisions with polarized protons in hadron colliders above 200 GeV are listed and briefly discussed. Particular attention is given to the use of the ''Siberan snake'' to eliminate depolarizing resonances, which occur when the spin precession frequency equals a frequency contained in the spectrum of the field seen by the beam. The Siberian snake is a device which makes the spin precession frequency essentially constant by using spin rotators, which precess the spin by 180/sup 0/ about either the longitudinal or transverse horizontal axis. It is concluded that operation with polarized protons should be possible at all the high energy hadron colliders. (LEW

ACCELERATION OF DEUTERONS OR ALPHA PARTICLES IN THE AGS. Internal Report

Possible experiments that could be performed at the Brookhaven alternating gradient synchrotron using highenergy deuterons and heavier nuclei are reviewed. Particular attention is given to production of high-energy neutrons by stripping. A brief analysis of changes needed to accelerate heavier nuclei reveals such modifications would not be prohibitive. (D.C.W.