Measurement of nanometer electron beam sizes with laser interference using Shintake Monitor

作者：Yan Jacqueline^*; Yamaguchi Yohei; Kamiya Yoshio; Komamiya Sachio; Oroku Masahiro; Okugi Toshiyuki; Terunuma Nobuhiro; Kubo Kiyoshi; Tauchi Toshiaki; Urakawa Junji

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2014, 740: 131-137.

DOI：10.1016/j.nima.2013.11.041

• ILC
• Laser
• IP
• Beam size
• Shintake Monitor

The Shintake Monitor is an essential beam tuning device installed at the interaction point (IF) of ATF2 [1], the final focus test beam line of the Accelerator Test Facility (ATF) to measure its nanometer order vertical e beam sizes (sigma(y)*). The e beam collides with a target of laser interference fringes, and sigma(y)* is derived from the modulation depth of the resulting Compton signal photons measured by a downstream photon detector. By switching between several laser crossing angle modes, it is designed to accommodate a wide range of sigma(y)* from 20 nm to a few micrometers with better than 10% accuracy. Owing to this ingenious technique, Shintake Monitor(1) [2,3] is the only existing device capable of measuring sigma(y)* < 100 nm, and is crucial for verifying AM's Goal 1 of focusing sigma(y)* down to the design value of 37 nm. Shintake Monitor has demonstrated stable sigma(y)* measurement with 5-10% stability. Major improvements in hardware and measurement schemes contributed to the suppression of error sources. This paper describes the design concepts and beam time performance of Shintake Monitor, as well as an extensive study of systematic errors with the aim of precisely extracting sigma(y)* from the measured modulation.

• 出版日期2014-3-11