FLS 2006 - List of Keywords (radiation)

A B C D E G I L O P Q R S U V

radiation

Paper	Title	Other Keywords	Page
PLT14	Short Radiation Pulses in Storage Rings	electron, laser, storage-ring, synchrotron	14
	S. Khan Uni HH, Hamburg
	Funding: Funded by the Bundesminister für Bildung und Forschung and by the Land Berlin The time resolution of experiments with synchrotron radiation, presently limited by a typical bunch length of 30–100 ps in electron storage rings, can be improved by making the bunches shorter (e.g. reducing the momentum-compaction factor or increasing the rf gradient) or by establishing a temporal-transverse correlation (e.g. transverse rf deflection or fs-laser slicing). Several methods, their present status and their respective merits or shortcomings are discussed.
	Slides

PLT31	Summary of WG1 – Storage Ring Based Radiation Sources	storage-ring, emittance, lattice, photon	18
	K. C. Harkay ANL, Argonne, Illinois A. Ropert ESRF, Grenoble
	Summary of the Storage Ring Based Radiation Sources working group The proposed topics of discussion in the Storage Ring Radiation Sources Working Group are presented. The questions addressed to the participants are the following: What ring parameters may lead to new science? Can we go beyond the present state of the art sources? What critical accelerator technologies require development? Upgrade of existing sources: What is feasible? Is it worth building cost-effective but lower performing rings? Should we build multipurpose or specialised sources?
	Slides

WG112	Proposal of a Synchrotron Radiation Facility to Supply Ultraviolet Light, X-Ray, MeV-photon, GeV-photon and Neutron	laser, photon, synchrotron, electron	24
	Y. Kawashima JASRI/SPring-8, Hyogo-ken
	This is a proposal of new facility, which consists of 1 GeV-linac, booster synchrotron and storage ring. The synchrotron accelerates electron beam from 1 GeV to 10 GeV. The storage ring stores the beam at arbitrary energy from 1 GeV to 10 GeV and top-up operation is carried out at any stored beam energy. The stored beam current depends on the beam energy. In the energy region of 8 GeV to 10 GeV, maximum beam current is around 100mA. Under the energy of 4 GeV, the targeted maximum current is 1 A. The storage ring supplies ultraviolet light, MeV-photon, GeV-photon and neutron for solid-state physics, biology, protein structure analysis, drug development and particle physics. The main feature of the facility is to be able to supply the monoenergetic MeV-photon and neutron. With CO₂ laser and stored electron beam, monoenergetic MeV-photons are produced through the inverse Compton process. To obtain the target monoenergetic MeV-photon, the wavelength of the laser is constant; on the other hand stored beam energy is changed. Using a superconducting wiggler, a lot of MeV photons are radiated from the wiggler. With the radiated MeV-photon and beryllium target, neutrons are produced.

WG343	Production of Coherent X-Rays with a Free-Electron Laser Based on Optical Wiggler	laser, electron, emittance, collective-effects	39
	C. Maroli, V. Petrillo Universita' degli Studi di Milano, Milano A. Bacci INFN/LASA, Segrate (MI) M. Ferrario INFN/LNF, Frascati (Roma) L. Serafini INFN-Milano, Milano
	Funding: Istituto Nazionale di Fisica Nucleare(INFN) - Sezione di milano The interaction between high-brightness electron beams and counter-propagating laser pulses produces X-rays via Thomson scattering. If the laser source is long enough the electrons bunch on the scale of the emitted X-ray wavelength and a regime of collective (coherent) emission can be established. The emitted radiation grows exponentially and the system behaves as a FEL with optical undulator. The bandwidth of the emitted X-rays is sharper than that of the usual incoherent emission. Emittance of the beam and gradients and irregularities of the laser intensity spatial distribution are the principal factors that limit the growth of the X-ray signal. The characters of the emission and the corresponding X-ray spectra are analyzed on the basis of a 3D code. The scalings typical of the optical wiggler with very short gain lengths and short time duration of the ineteraction allow considerable emissions also in violation of criteria valid for static wigglers. The parameters chosen in the cases examined allow a classical treatment of the lasing process.
	Slides

WG512	Longitudinal Diagnostics with THz Radiation	diagnostics, electron, linac, synchrotron	48
	H. Delsim-Hashemi, P. Schmüser Uni HH, Hamburg O. Grimm, B. Schmidt DESY, Hamburg
	According to the FEL theory, the longitudinal charge distribution in an electron bunch has an important effect on lasing process. For FLASH at DESY, structures in the order of 10 μm play a crucial role in SASE production. The investigation of the electron bunch longitudinal charge distribution and its bunch to bunch changes is one of the most important issues for optimizing the operation of the machine and improving its stability. Single shot spectroscopic in the 10–200 μm regime is beyond the capability of existing spectroscopic diagnostic tools. This paper introduces a new diagnostics method based on fast spectrally resolved detection of coherent infrared radiation from electron bunches. Measurement results at FLASH with this spectrometer in both scanning mode and single shot mode are presented and discussed.
	Slides

WG517	X-ray Pulse Length Characterization Using the Surface Magneto Optic Kerr Effect	laser, polarization, electron, photon	51
	P. Krejcik SLAC, Menlo Park, California
	It will be challenging to measure the temporal profile of the hard X-ray SASE beam independently from the electron beam in the LCLS and other 4th generation light sources. A fast interaction mechanism is needed that can be probed by an ultra-fast laser pulse in a pump-probe experiment. It is proposed to exploit the rotation in polarization of light reflected from a thin magnetized film, known as the surface magneto optic Kerr effect (SMOKE), to witness the absorption of the X-ray pulse in the thin film. The change in spin orbit coupling induced by the X-ray pulse occurs on the sub-femtosecond time scale and changes the polarization of the probe beam. The limitation to the technique lies with the bandwidth of the probe laser pulse and how short the optical pulse can be made. The SMOKE mechanism will be described and the choices of materials for use with 1.5 Å X-rays. A schematic description of the pump-probe geometry for X-ray diagnosis is also described.
	Slides