Synchrotron Facilities And Free El t Electron Lasers L Vashek Vylet, TJNAF James Liu, SLAC James Liu, SLAC HPS Professional Development School, Oakland, CA January 31 – February 2 2, 2008
Overview Introduction S S SR Sources: Dipole and Insertion Devices i l d i i SR Facilities: Components, Operation, RP SR Beamlines: Components, Hazards, g , y y Shielding Calculations, Safety System • Free Electron Lasers
• • • •
INTRODUCTION
INTRODUCTION • What What is Synchrotron Radiation (SR)? is Synchrotron Radiation (SR)? • SR is elmag radiation emitted when a charged particle travels along a curved trajectory particle travels along a curved trajectory. • Di Discovered as byproduct at first d b d fi synchrotrons (causing problems) • Soon applications were found, giving rise to 1st generation of SR facilities
N S
e-
B N S
Generations of SR Facilities Generations of SR Facilities • 1st generation SR facilities: running in parasitic generation SR facilities: running in parasitic mode, not optimized for SR production • 2nd generation SR facilities were first facilities generation SR facilities were first facilities dedicated solely to SR. High & stable current and large number of beam lines for users and large number of beam lines for users • 3rd generation: optimized to increase brilliance and use of insertion devices d fi i d i • 4th generation: FELs
Which particles? Which particles? • SR SR power radiated by a particle of mass m power radiated by a particle of mass m is is proportional to m‐4 • Most SR facilities therefore use electrons, some use positrons (ALS) some use positrons (ALS)
SR Applications SR Applications eV
m
7
SR Applications SR Applications • Biology: Biology: protein crystallography, drug design, protein crystallography drug design dynamic studies of cellular/viral processes… • Material science: crystallography, surface Material science: crystallography surface studies, changing material properties • Chemistry: molecular structure, dynamics of Ch i l l d i f chemical processes • Microchip lithography, micro‐welding, … gy • Nanotechnology
SR Facilities SR Facilities • Probably Probably over 100 SR facilities around the over 100 SR facilities around the world • Large national and multinational centers: Large national and multinational centers: ESRF(EU), SPRING8(JP), PAL(KO), BESY‐II (GE), Diamond (GB) Diamond (GB), … • US: NSLS, SSRL, ALS, APS, … • Smaller facilities at a number of universities and industry
SR SOURCES
SR Sources SR Sources • When a charge moves, information (el. field) is transmitted @ speed of light – spherical wave. Angle‐dependent Doppler shift occurs at electron velocities approaching speed of light.
Adapted from D. Attwood, UC Berkeley
v