Speaker
Ms
Jacqueline Yan
(University of Tokyo, School of Science)
Description
One of ATF2’s major goals is to verify the Local Chromaticity Correction scheme by focusing the vertical e- beam size (σy ) down to its design 37 nm. Indispensable for this mission and for R&D of future linear colliders is the Shintake Monitor installed at ATF2’s virtual IP. It is the only existing beam size monitor capable of measuring σy < 100 nm. , The e- beam is collided against laser interference fringes, and σy is derived from the modulation depth of the resulting Compton scattered photons. A wide measurable range from 20 nm to a few μm, is enabled by switching between several laser crossing angle modes.
σy < 150 nm have been achieved by Feb, 2012. Major upgrades in the laser optics suppressed various systematic errors and signal jitters, improved resolution, and led to remarkably stable contribution during continuous ATF2 beam runs in 2012 winter, during which the smallest σy ever of about 70 nm had been confirmed. This record was renewed in spring 2013 to stable measurements ofσy < 60 nm. Further hardware upgrades and dedicated error studies are ongoing to realize focusing and stable measurement of σy < 50 nm.
Primary author
Ms
Jacqueline Yan
(University of Tokyo, School of Science)
