JASRI/SPring-8, Hyogo, Japan
A newly designed pulse-by-pulse X-ray beam position monitor (XBPM), which is photoemission type, has been demonstrated successfully in the SPring-8 synchrotron radiation beamline. Conventional XBPMs work in the direct-current (DC) mode, because it is difficult to measure a beam position in the pulse mode under the sever heat load condition. The key point of the design is aiming at improving heat-resistance property without degradation of high frequency property [1]. This monitor is equipped with microstripline structure for signal transmission line to achieve pulse-by-pulse beam position signal. A photocathode is titanium electrode that is sputtered on a diamond heat sink to achieve high heat resistance. We have manufactured the prototype, and demonstrated feasibility at the SPring-8 bending magnet beamline. As a result, we observed a unipolar single pulse with the pulse length of less than 1 ns FWHM and confirmed that it has pulse-by-pules position sensitivity [2]. Furthermore, this monitor can be also used in the direct-current mode with good stability and good resolution. The operational experience will be also presented.
[1] http://accelconf.web.cern.ch/AccelConf/medsi2016/papers/wepe10.pdf
[2] http://www.pasj.jp/webpublish/pasj2017/proceedings/PDF/THOM/THOM06.pdf
