Evidence of particle trapping has been observed in a beam driven Plasma Wake Field Accelerator (PWFA) experiment, E164X, conducted at the Stanford Linear Accelerator Center by a collaboration which includes USC, UCLA and SLAC. Such trapping produces plasma dark current when the wakefield amplitude is above a threshold value and may place a limit on the maximum acceleration gradient in a PWFA. T...

By MERLE LOVELL LEWIS, PH.D. AND ARNOLD G. WARE, P11.1). T HE CONCEPT of blood coagulationi has undergone drastic revision inn the past decade. A number of different names have beenn gin-cnn to the substannces in serum arid plasma w-hich accelerate the comnversiomn of prothrombin to thrombimn. In ann effort to resolve some of the resultant comnfusiomn inn nomenclature, the Josiah Macy Conferenc...

A fiber-based four-channel heterodyne interferometer has been developed to study the properties of pulsed plasma. The accuracy phase measurements was 0.03 rad, which corresponds an error in measuring concentration free electrons ± 1· 10 19 m -2 . Measurements electron density and plasma velocity accelerator have carried out.. Keywords: laser interferometer, interferometer.

A demonstration of high-quality electron beams from a plasma accelerator driven by low-energy, few-cycle duration laser pulse showcases promising low-cost alternative to large traditional accelerators.

The plasma wakefield accelerator (PWFA) concept has been proposed [1] as a potential energy doubler for present or future electron-positron colliders. Recent particle-in-cell (PIC) simulations have shown [2] that the self-fields of the required electron beam driver can tunnel ionize neutral Li, leading to plasma wake dynamics differing significantly from that of a preionized plasma. It has also...

A novel mechanism for generating large (> 1 GeV/m) accelerating wakes in a plasma is considered. We employ two slightly detuned counter-propagating laser beams, an ultra-short timing pulse and a long pump, which exchange photons and deposit the recoil momentum into the plasma electrons. A rapidly rising electron current is thereby generated, inducing an plasma wake with phase velocity equal to ...

In a visit on Oct. 28, 1996 to the Center for Ultrafast Optical Studies at U. Michigan I had interesting conversations with Gerard Mourou and Don Umstadter about possible mechanisms for positron production in a plasma that is illuminated with a strong laser. I argue that positron production via a trident process (which includes Bethe-Heitler pair production) involving an isolated nucleus is pos...

For particle-beam-driven plasma wakefield accelerators, a long and fully-ionized plasma is desirable. We describe an experiment at UCLA to develop a prototype of such plasma using a pulsed-current discharge. Scaling of the plasma density with glass-tube diameter and with discharge-circuit parameters is currently underway. We have found that 4 Torr of Argon can be fully ionized to a density of a...