TY - CPAPER
AU - Masaki, M.
AU - Shimosaki, Y.
AU - Takano, S.
AU - Takao, M.
TI - Novel Emittance Diagnostics for Diffraction Limited Light Sources Based on X-ray Fresnel Diffractometry
J2 - Proc. of IBIC2014
AB - A novel emittance diagnostics technique with high sensitivity using X-ray Fresnel diffraction by a single slit has been developed to measure micron-order electron beam sizes at insertion devices (IDs) of photon beamlines. The X-ray Fresnel diffractometry (XFD)* is promising for diagnostics especially of a so-called diffraction limited storage ring (DLSR) with ultra-low emittance. In the DLSR, due to inevitable field errors of strong quadrupole and sextupole magnets, unwanted distortion of lattice functions and local betatron coupling will result in a different light source size at each beamline. Therefore, measurements of electron beam sizes at the ID source points will be essential to ensure the absence of degradation of brilliance and transverse coherence of radiation at the beamlines. The XFD observes a double-lobed diffraction pattern that emerges by optimizing the single slit width. The principle is based on a correlation between the depth of a median dip in the double-lobed pattern and the light source size at the ID. The validity of the new technique was theoretically and experimentally studied. The achievable resolution of the XFD will be also discussed.
PB - JACoW
CY - Geneva, Switzerland
SP - 274
EP - 278
KW - emittance
KW - electron
KW - radiation
KW - diagnostics
KW - betatron
DA - 2014/10
PY - 2014
SN - 978-3-95450-141-0
UR - http://jacow.org/IBIC2014/papers/tuczb1.pdf
ER -