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Several recent reports have identified the scientific requirements for a future soft X-ray light source [1, 2, 3, 4, 5], and a high-repetition-rate free-electron laser (FEL) facility responsive to them is being studied at Lawrence Berkeley National Laboratory (LBNL) [6]. The facility is based on a continuous-wave (CW) superconducting linear accelerator with beam supplied by a high-brightness, high-repetition-rate photocathode electron gun operating in CW mode, and on an array of FELs to which the accelerated beam is distributed, each operating at high repetition rate and with even pulse spacing. Dependent on the experimental requirements, the individual FELs may be configured for either self-amplified spontaneous emission (SASE), seeded high-gain harmonic generation (HGHG), echo-enabled harmonic generation (EEHG), or oscillator mode of operation, and will produce high peak and average brightness X-rays with a flexible pulse format ranging from sub-femtoseconds to hundreds of femtoseconds. This new light source would serve a broad community of scientists in many areas of research, similar to existing utilization of storage ring based light sources. [ABSTRACT FROM AUTHOR]

Laser pump and X-ray probe core-level photoemission experiments probe surface photovoltage transients on p-type Si (111) surfaces. The data are consistent with a picture where the dynamics of mobile surface charge dominate the photovoltage shift, with changes in the surface-states charge density of only secondary importance. A value for the equilibrium band binding is determined, which suggests that a residual oxide layer reduces the density of surface states. [ABSTRACT FROM AUTHOR]

The development of high-resolution, grazing-incidence soft x-ray monochromators is discussed, and the performance of competing designs is reviewed in terms of efficiency, ultimate resolution, and order sorting. In particular, the characteristics of astigmatically corrected spherical grating monochromator systems (SGM) is examined. A new design is presented in which a variable angle premirror is used to eliminate the wavelength dependent image distance of the SGM and allows the use of order sorting ranges. The properties of a competing design using a plane variable angle premirror, plane grating, and spherical mirror combination are presented, and similarities between this and the corrected SGM are discussed. Flux and resolution data are presented for an undulator monochromator of this latter design. [ABSTRACT FROM AUTHOR]

A correction to the article "Compact cryogenically cooled Ti: Sapphire dual multi-kilohertz amplifiers for synchrotron radiation ultra-fast x-ray applications" which was published in May, 28 2013 issue of the journal is presented.