Plasma and Particle Beam Theory
My research interests are in advanced accelerator concepts, intense laser-plasma interaction and the basic equilibrium, stability, and radiation properties of intense charged particle beams. The research includes basic theory, simulation and the development of proof-of-principle experiments.
My current research is on wake excitation in plasma channels, collisionless relaxation in beam-plasma systems, neutrino factories and muon colliders, intense laser pulse compression in plasmas, and long timescale dynamics in nonneutral plasmas.
High-energy accelerators have served as the main tool with which physicists have explored the building blocks of matter for more than sixty years. During this time there has been an exponential increase in the energy of accelerated particles. This increase has been made possible by a combination of improvements in existing machines and the invention of new acceleration techniques. Historically, whenever a given type of accelerator has reached the limit of its performance, an innovative idea for particle manipulation, storage, cooling or acceleration has made possible experiments at ever higher energies. The US High Energy Physics community faces serious challenges over the next two decades. A new high-energy Hadron collider, the LHC, is being built at CERN, while there are no major new facilities planned for the US. This situation lends some urgency to innovation and the serious examination of new ideas.
A significant part of our research is on laser-plasma accelerators and intense muon beams for neutrino factories and colliders. These nascent concepts may turn into the workhorses of high-energy physics in the 21st century. Plasma accelerators, at lower energies, may be used to produce high density ultra-short bunches for a variety of applications. The propagation of intense short-pulse lasers in plasmas is rich in nonlinear phenomena. Prominent among these are parametric instabilities, such as Raman scattering. We are trying to exploit this instability as a mechanism for energy transfer between counter propagating plasma waves. This has the potential of achieving much higher laser intensities than can be realized with conventional chirped pulse amplification.
The concept of Muon-Muon Colliders originates in the 70’s. More recently, a collaboration led by BNL, FNAL and LBNL has undertaken detailed studies of the muon collider and the neutrino factory. Our research has been on the most challenging aspect of these machines, cooling the muon beam so that it can be accelerated.
A final area of research is on the theoretical understanding of nonneutral plasmas under conditions where the plasma dynamics closely resemble that of a two-dimensional Eulerian fluid.
J. S. Wurtele, “Advanced accelerator concepts,” Physics Today (1994).
J. S. Wurtele, “Towards very high-energy accelerators,” International Journal of Modern Physics A15, Suppl. 1B, (19th International Symposium on Lepton-Photon Interactions at High Energies, Stanford, CA, 9-14 Aug. 1999), World Scientific, 816-39 (2000).
E. Yu. Backhaus and J. S. Wurtele, “Coupled moment expansion model for the dynamics in a beam–plasma system,” Physics of Plasmas 7, 4729 (2000).
G. Penn and J. S. Wurtele, “Beam envelope equations for cooling of muons in solenoid fields,” Phys. Rev. Lett. 85, 764 (2000).
C. Schroeder, D. H. Whittum, and J. S. Wurtele, “Multimode analysis of the hollow plasma channel wakefield accelerator,” Phys. Rev. Lett. 82, 1177 (1999).
E. Yu. Backhaus, R. Govil, W. P. Leemans, and J. S. Wurtele, “Observation of return current effects in a passive plasma lens,” Phys. Rev. Lett. 83, 3202 (1999).
B. A. Shadwick and J. S. Wurtele, “General moment model of beam transport,” Proceedings of 1999 Particle Accelerator Conference, New York, 1999.