One loop photon-graviton mixing in an electromagnetic field: Part 2

In part 1 of this series compact integral representations had been obtained for the one-loop photon-graviton amplitude involving a charged spin 0 or spin 1/2 particle in the loop and an arbitrary constant electromagnetic field. In this sequel, we study the structure and magnitude of the various polarization components of this amplitude on-shell. Explicit expressions are obtained for a number of limiting cases.Comment: 31 pages, 3 figure

Commissioning of the European XFEL Injector

The European XFEL Injector consists of an L-Band RF photoinjector, a TESLA type 1.3 GHz module, a 3rd har-monic RF section, a laser heater and an extensive diag-nostic section to determine projected and slice properties of the beam. The commissioning of the complete system has been started in December 2015 after several years of construction. We will report on commissioning results and perspectives for the later XFEL operation

Pohang Light Source' Current Status and Future, and Synchrotron X-ray and HANARO Neutron Beam Applications in Polymer Science

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ESTIMATIONS FOR DEMAGNETIZATION OF ID PERMANENT MAGNETS DUE TO INSTALLATION OF OTR

Abstract Demagnetization due to installation of OTR to check the electron beam performance during the operation has been estimated for the permanent magnets of insertion device of XFEL/SPring-8. The estimation of the demagnetization has been performed quantitatively as functions of the electron energy, the gap width of the ID, and the dependence on material of the OTR

OPERATION STATUS OF C-BAND HIGH-GRADIENT ACCELERATOR FOR XFEL/SPRING-8 (SACLA)

Abstract To fit our XFEL machine of SACLA (SPring-8 Angstrom Compact Free Electron Laser) in the small campus of SPring-8, a C-band (5712 MHz) high-gradient accelerator with a designed acceleration gradient of 35 MV/m is indispensable. Highly-stable acceleration for an energy chirp in bunch compression process is required for stable lasing. The low-trip rate and the low-dark current of C-band accelerating structures are also crucial for stable accelerator operation. After 1000 hours of the RF conditioning, the C-band accelerator has daily accelerated electron beams up to 7.0-7.4 GeV, with the designed accelerator gradient of about 35 MV/m. The trip rate of the whole accelerator is once per 30 minutes, which is an acceptable rate for beam commissioning. The energy stability of the electron beam was 0.014% (STD), owing to the stabilization of a PFN charging voltage with a 10 ppm (STD) accuracy by a high-precision high-voltage charger. The amount of dark current was several pC/pulse, which was small enough for operation