Successful user operation of a superconducting radio-frequency photoelectron gun with Mg cathodes

At the electron linac for beams with high brilliance and low emittance (ELBE) center for high-power radiation sources, the second version of a superconducting radio-frequency (SRF) photoinjector has been put into operation and has been routinely applied for user operation at the ELBE electron accelerator. SRF guns are suitable for generating a continuous wave electron beam with high average currents and high beam brightness. The SRF gun at ELBE has the goal to generate short electron pulses with bunch charges of 200–300 pC at typical repetition rates of 100 kHz for the production of superradiant, coherent terahertz radiation. The SRF gun includes a 3.5-cell, 1.3-GHz niobium cavity and a superconducting solenoid. A support system with liquid nitrogen (LN2) cooling allows the operation of normal-conducting, high quantum efficiency photocathodes. We present the design and performance of the SRF gun as well as beam measurement results of the operation with Mg photocathodes at an acceleration gradient of 8  MV/m (4 MeV kinetic energy). In the last section, we discuss the SRF gun application for production of coherent terahertz radiation at the ELBE facility

Intense ultrashort terahertz pulses: generation and applications

TOPICAL REVIEW: Ultrashort terahertz pulses derived from femtosecond table-top sources have become a valuable tool for time-resolved spectroscopy during the last two decades. Until recently, the pulse energies and field strengths of these pulses have been generally too low to allow for the use as pump pulses or the study of nonlinear effects in the terahertz range. In this review article we will describe methods of generation of intense single cycle terahertz pulses with emphasis on optical rectification using the tilted-pulse-front pumping technique. We will also discuss some applications of these intense pulses in the emerging field of nonlinear terahertz spectroscopy

Immunohistochemical assessment angioarchitecture a vaginal side at women in a postovariectomy state

In article the disturbance problem of blood flow the vaginas of the woman in a state of a medicamental and surgical menopause after spent этиопатогенетического the treatment including total husterectomy, radiation therapy and polychemotherapy by results of an expression Cd34 and bloods steroid sexual hormonesis, in particular aestradiolum. Comparison with bunch of women in a state of the postovariectomy which have educed after surgical treatment concerning good-quality diseases of internial genital. The pathogenetic role of surgical and radial influences on a vagina of the woman is proved

Adjoint Calculation using Time-minimal Program Reversals For Multi-Processor Machines

For computational purposes such as debugging, derivative computations using the reverse mode of automatic differentiation, or optimal control by Newton's method, one may need to reverse the execution of a program. The simplest option is to record a complete execution log and then to read it backwards. As a result, massive amounts of storage are normally required. This pape