March 30, 2001

"Ultrabright Multikilovolt X-Ray Source for Biological Microimaging"
Charles Rhodes
Department of Physics
University of Illinois at Chicago

Detailed molecular structural information is of enormous significance to the medical and biological communities. Since hydrated biologically active structures are small delicate complex three-dimensional (3D) entities, it is essential to have molecular scale spatial resolution, high contrast, distortionless, direct 3D modalities of visualization of specimens in the living state in order to faithfully reveal their full molecular architectures. An x-ray holographic microscope equipped with an x-ray laser as the illuminator would be uniquely capable of providing these images. In this lecture, Dr. Rhodes will present specific findings which experimentally demonstrate that, at 2.9 angstroms, the operation of a new concept capable of producing the ideal conditions for amplification of multikilovolt x-rays and prove the feasibility of a compact x-ray illuminator that can cost-effectively achieve the mission of x-ray biological microholography and likewise serve an array of other applications involving the fabrication and measurement of solid state nanostructures.

Bio Sketch
Dr. Rhodes received a BEE and MEE from Cornell and MIT respectively and a Ph. D. in physics from MIT. He is The Albert A. Michelson Professor of Physics, a distinguished appointment in the University of Illinois system, Professor of Electrical Engineering and Computer Science, and the Director of the Laboratory for Experimental Astrophysics and Computational Cosmology in the Department of Physics.

His research, which combines experimental and theoretical components, has two main centers of activity. One involves advanced forms of X-ray generation and biological X-ray microholography. The second concerns multidisciplinary activity in Computational Physics which incorporates

• high power density plasmas,
• cosmology and particle physics, and
• protein structure and dynamics.

Additional activities outside of those described above include the pursuit of squash playing and the preparation of a book entitled, On Board the Heavenly Seesaw.

SMSI Minutes: 30 March 2001
Ultrabright Multikilovolt X-ray Source for Biological Microimaging by Charles K Rhodes.

With an efficient selective collisional ejection mechanism for inner shell population inversion in laser-driven plasmas (J. of Physics B 14 Feb. 01 v34 n3 297), Rhodes described the dynamics of optimized stable channel formation of intense laser pulses with the relativistic/charge-displacement mechanism (J of Physics B 28 July. 99 v32 n14 3511) and evidence of enhanced multiphoton (248nm) coupling from single-pulse energy measurements of Xe(L) emission induced from Xe clusters (J of Physics B 14 Nov. 97 v30 n21 L767) which produced stable self-channeling of intense ultraviolet pulses in underdense plasma, producing channels exceeding 100 Rayleigh lengths (J of the Optical Society of America B 1 Oct. 94 v11 n10 1941). It vaporized a 1.5 mm hole in a 12.5 mm Ti foil. The synchrotron hits a goal confined in one direction with vanishing density while the Xe(L) beam is solid density but with greater light and lower cost by magnitudes. Ni would be the best material as a spherical reference source.

Respectfully submitted 01 April 01, Stan Schmidt, Recording Secretary