Search

Beam position monitors (BPMs) with a resolution in a few nanometers range are required to control beams in the locations that are close to the interaction point (IP) of the international linear collider (ILC). ATF2 at KEK has considered as a test facility to investigate this requirement. In order to measure beam position stability at ATF2 final focus, a kind of IP-BPM has been developed at KEK and it has been tested in the ATF extraction line. We have designed an IP-BPM with lower Q-value than the IP-BPM in the extraction line in order to achieve smaller resolution. It enables easier separation of individual bunches in a multi-bunch signal. We have performed the design study for IP-BPM by using of the electromagnetic simulation program MAFIA and HFSS. The designed IP-BPM consists of one cell sensor cavity and one cell reference cavity. The results of the design studies showed signal decay time of 20 ns and the resolution of a few nm. We present the results of design studies in which include effects of common mode contamination in the IP-BPM, as well as preliminary test results on the proto-type IP-BPM.

A compact and high quality X-ray source is required from various fields, such as medical diagnosis, drug manufacturing and biological sciences. A laser-Compton based X-ray source that consists of a compact electron storage ring and a pulsed-laser super-cavity is one of the solutions for a compact X-ray source. A pulsed-laser super-cavity has been developed for a compact high brightness X-ray sources at KEK-ATF. The pulsed-laser super-cavity increases the laser power and stably makes small laser beam size at the collision point with the electron beam. Recently, 357 MHz mode-locked Nd:VAN laser pulses can be stacked stably in a 420 mm long Fabry-Pe acuterot cavity with 600 enhancement in our R&D. Therefore, we have planned a compact hard X-ray source using 40 MeV multi-bunch electrons and a pulse stacking technology with 42 cm Fabry-Pe acuterot cavity (LUCX Project at KEK). The photon flux is multiplied with the number of bunches by using multi-bunch beam and a super-cavity. Development of the super-cavity and present results of LUCX will be presented at the conference.