scholarly journals High‐resolution beamline 9.3.2 in the energy range 30–1500 eV at the Advanced Light Source: Design and performance

1996 ◽  
Vol 67 (9) ◽  
pp. 3372-3372 ◽  
Author(s):  
Z. Hussain ◽  
W.R.A. Huff ◽  
S.A. Kellar ◽  
E.J. Moler ◽  
P.A. Heimann ◽  
...  
1997 ◽  
Vol 68 (5) ◽  
pp. 1945-1951 ◽  
Author(s):  
P. A. Heimann ◽  
M. Koike ◽  
C. W. Hsu ◽  
D. Blank ◽  
X. M. Yang ◽  
...  

2016 ◽  
Vol 30 (15) ◽  
pp. 1650204 ◽  
Author(s):  
Jun Li ◽  
Jian Dang Liu ◽  
Song Bin Zhang ◽  
Bang Jiao Ye

K-shell photoionization (PI) of Li, Be[Formula: see text] and B[Formula: see text] from ground state [Formula: see text] have been studied by using the [Formula: see text]-matrix method with pseudostates. The K-shell PI process is featured with the contributions from the core-excited metastable states or dominated by the Auger states 2Po. The resonant parameters of the Auger states 2Po and the PI cross-sections have been calculated and compared with the available experimental and theoretical works. Our results agree very well with that of the published works. It is worth noting that compared with previous theoretical calculations, our results of B[Formula: see text] show better agreements with the latest high-resolution advanced light source measurements [A. Müller et al., J. Phys. B 43 (2010) 135602].


Author(s):  
W. Meyer-Ilse ◽  
H. Medecki ◽  
C Magowan ◽  
R. Balhorn ◽  
M. Moronne ◽  
...  

A new x-ray microscope (XM-1) has been installed at the Advanced Light Source in Berkeley. This transmission microscope uses zone-plates for a resolution exceeding visible light microscopies. Samples can be as thick as 10 microns, for wet or dry specimens. These features make x-ray microscopy a valuable complement to other advanced techniques.There are two types of x-ray microscopes, scanning and conventional (imaging) microscopes. The scanning type minimizes radiation dose to the sample and is convenient for high resolution use of fluorescent labels; however, it requires a spatially coherent x-ray source and as a result involves long exposure times. The conventional type provides a higher potential for ultimate resolution as there is no scanning stage needed, and it can operate with an incoherent light source. It therefore has a shorter exposure time, but does require a higher radiation dose due to lens inefficiencies. The new XM-1 is of the second type. Its optical layout is very similar to the Gottingen x-ray microscope operated at the BESSY facility in Berlin, Germany.


2020 ◽  
Vol 27 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Aleksandr Kalinko ◽  
Wolfgang A. Caliebe ◽  
Roland Schoch ◽  
Matthias Bauer

The design and performance of the high-resolution wavelength-dispersive multi-crystal von Hamos-type spectrometer at PETRA III beamline P64 are described. Extended analyzer crystal collection available at the beamline allows coverage of a broad energy range from 5 keV to 20 keV with an energy resolution of 0.35–1 eV. Particular attention was paid to enabling two-color measurements by a combination of two types of analyzer crystals and two two-dimensional detectors. The performance of the spectrometer is demonstrated by elastic-line and emission-line measurements on various compounds.


1996 ◽  
Vol 74 (11-12) ◽  
pp. 713-721 ◽  
Author(s):  
Michael S. Lubell

The Advanced Light Source (ALS) at Lawrence Berkeley Laboratory is a "third generation" synchrotron radiation machine that incorporates wigglers and undulators to enhance the spectral brightness of the emitted radiation. Commissioned in October 1993, its performance to date has been nothing short of spectacular. Its demonstrated characteristics make it an ideal tool for carrying out high resolution measurements of photoionization studies of two-electron atomic and ionic systems. ALS Beamline 9.0.1, a facility dedicated to the study of photoprocesses in atoms, molecules, and ions, utilizes an undulator with an 8 cm period and a monochromator with spherical gratings to produce light at energies between 20 and 300 eV. At a photon energy of, 50 eV, the beamline is designed to deliver about 1.5 × 1013 photons/s into a spot measuring approximately 50 × 800 μm with a resolving power of 10 000. Measurements of low-lying autoionizing resonances in He, carried out shortly after the ALS was commissioned, provided the first confirmation of the essential beamline characteristics. The 1.0 meV line width, more recently observed for the 2p3d double-excitation state of He at 64.12 eV, demonstrates that the actual resolving power of the beamline far exceeds the design value. The properties of the ALS, combined with improvements in the reliability and operating characteristics of ion sources, make it possible to extend high-resolution synchrotron experiments beyond the study of neutral systems. Investigations of low-Z ions are important, because they provide an easy way to vary the relative contribution of the electron–electron interaction. An international collaboration has recently been formed to perform such studies. Its list of priorities includes the doubly excited spectra and the threshold region for two-electron photoionization in Li+ and H−. Metastable He*, formed by resonant charge transfer from He+, will provide access totriplet states.


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