Free electron laser facilities

Figure 12-3. IR-UV double resonance spectrum of GC (structure C) in the mid-IR frequency range (recorded at the FELIX free electron laser facility), compared with three types of ab intio calculations. Harmonic frequencies were obtained at the RI-MP2/cc-pVDZ, RI-MP2/TZVPP, and semiempirical PM3 levels of electronic structure theory. Anharmonic frequencies were obtained by the CC-VSCF method with improved PM3 potential surfaces [30]...

The experiments described here were performed on a guided ion beam tandem mass spectrometer [18] that was temporarily installed at the free electron laser facility FELIX (free electron laser for infrared experiments, FOM Institute for Plasma Physics, Nieuwegein, The Netherlands) [19]. A schematic of the experimental setup is shown in Fig. 3.2. Ions are generated in the ion source region (not... 

Transition radiation is considerably weaker than Cerenkov radiation, however since it is a surface phenomenon it avoids problems with radiator thickness and reflections inherent to Cerenkov-generating silica plates. Optical TR can be measured using a streak camera. An optical TR system has been used to time-resolve the energy spread of an electron macropulse in a free-electron laser facility [10]. Interferometry of coherent, far-infrared TR has been used to measure picosecond electron pulse widths and detect satellite pulses at the UCLA Satumus photoinjector, using charges on the order of 100 pC [11],... 

Table X lists Free Electron Laser Facilities and their typical parameter values.

On the other hand, synchrotron X-rays have a distinct advantage, which is the relatively high flux density of radiation. Synchrotron X-ray beams can routinely deliver six orders of magnitude more (monochromatic) X-ray photons (per unit area per unit time) than the best neutron sources available at present. With the advent of free electron laser facilities, the flux difference is expected to grow even larger. 

Oepts D, van der Meer AFG, van Amersfoort PW (1995) The free-electron-laser facility FELIX. Infrared Phys Technol 36 297-308... 

A VUV Free Electron Laser at the TESLA Test Facility at DESY -Conceptual Design Report (DESY Print, Hamburg 1995). 

The RF photocathode electron gun is the newest type of accelerator used for pulse radiolysis. Such devices have been under development since the mid-1980s as electron beam sources for experimental physics facilities and free-electron laser development. They are typically used to produce electron beams in the 4-10-MeV range. The unique quality (low emittance and clean position-momentum relationships) of the electron beams they produce makes extremely sophisticated beam manipulation possible. 

VaUe, J.J. Eyler, J.R. Oomens, J. Moore, D.T. van der Meer, A.F.G. von Helden, G. Meijer, G. Hendrickson, C.L. Marshall, A.G. Blakney, G.T. Free electron laser-Fourier transform ion cyclotron resonance mass spectrometry facility for obtaining infrared multiphoton dissociation spectra of gaseous ions. Rev. Sci. Instrum. 2005, 76.023103. 

In conclusion, free-electron laser research and development is international in scope with a wide range of experiments and user facilities either in operation or in the planning stages throughout the United States, Etrrope,... 

FIGURE 11 The average brilliance predicted for the Linac Coherent Light Source (LCLS) and TESLA Test Facility (TTF) free-electron laser (FEL) facilities in comparison with present-day synchrotron light sources. APS, ESRF, ALS, SBLC. 

R. Bonifacio, C. Pellegrini, I.M. Narducci Opt. Commun. 50, 373 (1984) A VUV Free Electron Laser at the TESLA Test Facility at DESY Conceptual Design Report (DESY Print, Hamburg 1995)... 

Valle JJ, Eyler JR, Oomens J, Moore DT, van der Meer AFG, von Helden G, Meijer G, Hendrickson CL, Marshall AG, Blakney G (2005) free electron laser-Foniier transform ion cyclotron resonance mass spectrometry facility for obtaining infinred multiphoton dissociation spectra of gaseous ions. Rev Sci Instrum 76 023103... 

Unfortunately, powerful IR lasers tunable over a significant frequency range are difficult to obtain. Currently, the most effective but highly demanding approach to this end is represented by the free-electron laser (FEL). FEL facilities are limited and offer access for researchers to perform their experiments at dedicated ports on a tight schedule (Fig. 9.35). Alternatively, optical parametric oscil-lator/amplifiers (OPO/As) can serve as tunable IR light sources [139,156]. 

A few interesting sources for future FT-IR spectrometers have been reported in the past 10 years, including the synchrotron and free electron laser (FEL) [4]. Using the radiation from a synchrotron beam line, spectra of samples as small as 10 pm in diameter (the diffraction Unfit) may be measured with veiy high SNR in times as short as 1 second. Obviously the use of these sources requires the spectroscopist to travel to a synchrotron or FEL facility with a mid-infrared beam line equipped with a FT-IR nficrospectrometer. Such facilities are available in several countries and can be used at minimal cost provided that the potential user can make a good case for the measurement... 

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