MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October 1999 An X-Band Photoinjector for Intense MM-Wave and Tunable X-Ray Generation E.C. Landahl, H. A. Baldis, J.E. Boggan, D. Gibson, F.V. Hartemann, J.P. Heritage, C.H. Ho (a), K. Li, E. Schamiloglu (b), A.L. Troha, N.C. Luhmann, Jr. University of California, Davis, CA Lawrence Livermore National Laboratory, Livermore, CA (a) Synchrotron Radiation Research Center, Hsinchu, Taiwan (b) Department of Electrical and Computer Engineering, University of New Mexico

MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October 1999 Chirped-Pulse Free-Electron Maser Seed Pulse Pre-bunched Electron Beam Diffraction Grating Amplified Output Pulse Smith-Purcell Maser (in collaboration with UNM)

MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October 1999 UC Davis X-Band Photoinjector

MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October MW X-Band RF System Tuning Curve Pulse Amplitude

MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October 1999 Recent X-Band RF Gun Results In Phase Gun Probes Signal 

MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October 1999 Compact Tunable X-Ray Source for Biomedical Applications is a Spin-Off of MURI Funded Research The photoinjector parameters are also optimal for x-ray generation Facilities developed for FEL research are currently being upgraded

MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October 1999 High Brightness X-Rays for Medicine “Brightness” is the Figure Of Merit for electromagnetic radiation sources in many applications The brightness of a light source determines how much spectral power can be delivered to a particular volume Brightness = Photons/second/area/solid-angle/bandwidth Blackbody Radiation Bremsstrahlung Spontaneous Emission Synchrotron Radiation Lasers (Low Brightness Sources) (High Brightness Sources) Existing medical x-ray sources combine bremsstrahlung (radiation by electrons as they slow down while passing through material) with K-shell emission lines and result in a wide x-ray energy spectrum The Compton scattering x-ray source uses relativistic electrons moving in response to applied EM fields in a manner similar to synchrotrons except that lasers rather than magnets provide the “wiggler” field to create discrete x-ray energies

MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October 1999 High Brightness X-Rays for Medicine The utility of high brightness x-rays for medical imaging has been demonstrated at synchrotron radiation facilities Breast tissue biopsy study (Reproduced from Radiology 1995; 195: ; permission courtesy of M. Gambaccini) X-ray imaging using a conventional x-ray source (left); the same sample examined using synchrotron radiation showing considerably more detail (right) Early detection of small cancers enhances significantly the probability for successful treatment and recovery Additional advanced imaging and treatment methods may be developed with high brightness x-rays, including subtraction imaging with Contrast Enhancing Media, chemical tagging (via monoclonal antibodies or other chemical markers), phase-contrast imaging, x-ray phototherapy, and gamma-ray “scalpels”

MVE MURI 99 Kick-off Meeting R. Barker, Technical Monitor Started 1 May 99 October 1999 Development of a Compact Compton Scattering X-Ray Source Developments in high-gradient, high-frequency electron accelerators and synchronized state-of-the-art high peak power ultrashort lasers are being combined to create a clinically feasible high brightness x-ray source in our laboratory at LLNL. The emphasis on compact systems in the MURI program (efficient lasers, high gradient accelerators) is a feature of our x-ray effort which is important to the medical community. Existing high-brightness x-ray sources either do not provide the required x-ray energies and average powers for medical applications (e.g. plasma x-ray lasers) or are too large and expensive for use in a clinical environment (synchrotrons, shown at left) High brightness x-rays are also critical to advances in surface science and protein crystallography, among other fields. 1/2 mile 30 feet 10 feet Advanced Photon Source, Argonne, IL