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Paper	Title	Other Keywords	Page
MOO3A01	Optical Transition Radiation Monitor for High Intensity Proton Beam at the J-PARC	radiation, target, proton, beam-losses	30
	A. Toyoda, A. Agari, E. Hirose, M. Ieiri, Y. Katoh, M. Minakawa, H. Noumi, Y. Sato, Y. Suzuki, H. Takahashi, M. Takasaki, K. H. Tanaka, H. Watanabe, Y. Yamanoi KEK, Tsukuba
	The OTR is a powerful tool to observe 2-dimensional information of beam profile at the high intensity beamline because the OTR intensity only depends on the screen reflectivity so that we can minimize a beam loss. However, it is necessary to overcome large background due to the Cerenkov radiation and low radiation tolerance of camera system. The purpose of the present effort is to achieve small background and good S/N and to prolong the lives of the camera system. This requires that amount of potential Cerenkov radiator be minimized and radiation level at the camera system be suppressed. For this requirement, we design and develop an OTR monitor with the optical system of a Newtonian telescope type. Detail design of the optical system and a result of background measurement performed at one of primary proton beam lines of our old 12 GeV Proton Synchrotron will be presented.
MOO3A02	Beam Induced Fluorescence (BIF) Monitor for Transverse Profile Determination of 5 to 750 MeV/u Heavy Ion Beams	ion, vacuum, photon, electron	33
	F. Becker, C. A. Andre, P. Forck GSI, Darmstadt D. Hoffmann TU Darmstadt, Darmstadt
	In the frame of the FAIR-project (facility for antiproton and ion research) at GSI, high intensity beams from protons to Uranium ions in the energy range from 100 MeV/u to 30 GeV/u are foreseen. In transport lines between the synchrotrons and in front of production targets a precise beam alignment is mandatory. Since the beam energy will increase from 90 Joule to about 104 Joule per ion pulse, conventional intercepting beam diagnostics may not be used. For transverse profile determination we investigated a non-intercepting Beam Induced Fluorescence (BIF) monitor in residual nitrogen. An image intensified CCD camera was used to record the fluorescence images representing the beam profile. The photon yield and background contribution were determined for different ion species, beam energies and N2 pressures. Applying narrowband 10 nm interference filters we mapped the spectral response and associated it with the N2 transitions. Profile distortions were compared to simulations taking into account effects as momentum transfer, gas dynamics and the electrical field of the ion beam. Additionally the feasibility and appropriate layout for different diagnostic tasks is discussed.
	Slides
TUPB01	A Fiber Profile Monitor for low Beam Intensities.	vacuum, secondary-beams, target, controls	51
	G. R. Tassotto, H. Nguyen, D. P. Schoo, G. W. Sellberg Fermilab, Batavia, Illinois
	A scintillating Fiber Profile Monitor (FPM) has been prototyped, built and tested for the new low intensity Meson Test (M-Test) beamline at Fermilab. The beamline has the following beam parameters: E = 1-120 GeV, I from a few hundreds to 700,000 particles/spill, and the spill length is 4.5 seconds. Segmented Wire Ion Chambers (SWICs) and Proportional Wire Chambers (PWCs) do not display the beam profile accurately below about 10,000 particles. For the prototype FPM detector a modified SWIC vacuum can was used. An (x, y) array of fibers replaced the chamber containing windows, gas, and AuW wires soldered on a ceramic substrate. The fibers were purchased from Saint Gobain and are of the type BCF-12 MC, 420 nm wavelength They have a diameter of 0.75 mm and are coated with black EMA for optical isolation. The 64 channel fibers are positioned and then epoxied in a vacuum feed-thru “cookie” to match a Burle 64 channel multianode microchannel plate PMT of the type Planacon # 85011-501. The gain of the Planacon PMT is 800,000 at –2400 Volts. Unlike SWICs or PWCs, this device will allow for vacuum continuity. Comparative data with PWCs will be presented.