Naumenko, A.

Paper	Title	Page
THOALH02	Development of the Non-invasive Beam-size Monitor using ODR	256
	T. Muto, S. Araki, H. Hayano, V. Karataev, N. Terunuma, J. Urakawa KEK, Ibaraki R. Hamatsu TMU, Hatioji-shi,Tokyo A. Naumenko, A.P. Potylitsyn Tomsk Polytechnic University, Physical-Technical Department, Tomsk
	The beam-size monitor based on Optical Diffraction Radiation (ODR) has been developed at the KEK-ATF. Because of its non-invasive nature, the ODR monitor might be one candidate to measure the extreme-low emittance electron beam for future LC?s and x-ray free electron lasers. To evaluate the beam-size, the angular distribution of the ODR emitted by the beam when crossing a slit in a metallic foil was measured. In the first trial, we observed interference patterns between ODR and backgrounds which may be the synchrotron radiation from most nearest bending magnet at the ATF extracted line. By the installation of the ceramic mask in front of our target, this interference was vanished. And comparing with the result of ODR measurements, we installed the wire scanner in the same position of our monitor. In this paper, we will present developments of the ODR monitor with some experimental results.
	Video of talk
	Transparencies
THPLT067	Development of Optical Diffraction Radiation Beam Size Diagnostics at KEK Accelerator Test Facility	2643
	V. Karataev, H. Hayano, T. Muto, N. Terunuma, J. Urakawa KEK, Ibaraki R. Hamatsu TMU, Hatioji-shi,Tokyo A. Naumenko, A.P. Potylitsyn Tomsk Polytechnic University, Physical-Technical Department, Tomsk
	Extremely low emittance high current beam is required for the accelerators of the next generation such as linear collider to achieve a reasonable luminosity. However, up to now there is no a simple non-invasive technique for beam diagnostics. A method based on optical diffraction radiation (ODR) appearing when a charged particle passes through a slit between two semi-planes can be one of the promising approaches. The estimations show that it might be possible to measure the beam size as small as 10mcm for a single shot. For a test of the proposed technique we designed an experimental setup and installed it at the extraction line of the KEK-ATF (1.26GeV beam energy, 1010 e/bunch, rms beam size > 10mcm). The electron beam was moving through a 0.26mm wide slit. We have measured backward ODR angular distribution. We have observed the beam size effect on the measured quantities. The sensitivity to the beam size as small as 20mcm was achieved. However, some undesirable factors such as X-ray background, SR photons coming through the mask slit, big detector angular acceptance have to be reduced. In this case a few micrometers beam size could be measured.