FROAN —  Sources and Medium Energy II   (01-Apr-11   08:30—09:30)
Chair: K.W. Jones, LANL, Los Alamos, New Mexico, USA

Paper	Title	Page
FROAN1	The European Spallation Source	2549
	S. Peggs, H. Danared, M. Eshraqi, H. Hahn, A. Jansson, M. Lindroos, A. Ponton, K. Rathsman, G. Trahern ESS, Lund, Sweden S. Bousson IPN, Orsay, France R. Calaga BNL, Upton, Long Island, New York, USA G. Devanz, R.D. Duperrier CEA/DSM/IRFU, France J. Eguia Fundación TEKNIKER, Eibar (Gipuzkoa), Spain S. Gammino INFN/LNS, Catania, Italy S.P. Møller ISA, Aarhus, Denmark C. Oyon SPRI, Bilbao, Spain R.J.M.Y. Ruber Uppsala University, Uppsala, Sweden T. Satogata JLAB, Newport News, Virginia, USA
	The European Spallation Source (ESS) is a 5 MW, 2.5 GeV long pulse proton linac, to be built and commissioned in Lund, Sweden. The Accelerator Design Update (ADU) project phase is under way, to be completed at the end of 2012 by the delivery of a Technical Design Report. Improvements to the 2003 ESS design will be summarised, and the latest design activities will be presented.
	Slides FROAN1 [1.650 MB]
FROAN2	DIANA, a Next Generation Deep Underground Accelerator Facility	2552
	D. Leitner NSCL, East Lansing, Michigan, USA M. Couder, M. Wiescher Notre Dame University, Notre Dame, Iowa, USA A. Hodgkinson, A. Lemut, J.S. Saba LBNL, Berkeley, California, USA M. Leitner FRIB, East Lansing, Michigan, USA
	Funding: This work was supported by the National Science Foundation NSF-09-500 grant (DUSEL S4), Proposal ID 091728 DIANA (Dakota Ion Accelerators for Nuclear Astrophysics) is a next generation nuclear astrophysics accelerator facility proposed to be built as part of the US DUSEL (Deep Underground Science and Engineering Laboratory) project. The scientific goals of DIANA are focused on experiments related to nucleosynthesis processes. Reaction cross-sections at stellar temperature are extremely low, which makes these experiments challenging. Small signal rates are overwhelmed by large background rates associated with cosmic ray-induced reactions, background from natural radioactivity in the laboratory environment, and the beam-induced background on target impurities. By placing the DIANA facility deep underground (1.4 km) the cosmic ray induced background can be eliminated. In addition, the DIANA accelerator is being designed to achieve large laboratory reaction rates by delivering high ion beam currents (up to 100 mA) to a high density super-sonic jet-gas target (up to 1018 atoms/cm2). Two accelerators are coupled to enable measurements over a wide energy range from 30 keV to 3 MeVin a consistent manner. The accelerators design and its technical challenges are presented.
	Slides FROAN2 [4.231 MB]
FROAN3	High-Intensity, High-Brightness Polarized and Unpolarized Beam Production in Charge- Exchange Collisions	2555
	A. Zelenski, G. Atoian, J. Ritter, D. Steski, V. Zubets BNL, Upton, Long Island, New York, USA V.I. Davydenko, A.V. Ivanov, V.V. Kolmogorov BINP SB RAS, Novosibirsk, Russia
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Basic limitations on the high-intensity H− ion beam production were experimentally studied in charge-exchange collisions of the neutral atomic hydrogen beam in the Na- vapor jet ionizer cell. These studies are the part of the polarized source upgrade (to 10 mA peak current and 85% polarization) project for RHIC. In the source the atomic hydrogen beam of a 3-5 keV energy and total (equivalent) current up to 5 A is produced by neutralization of proton beam in pulsed hydrogen gas target. Formation of the proton beam (from the surface of the plasma emitter with a low transverse ion temperature ~0.2 eV) is produced by four-electrode spherical multi-aperture ion-optical system with geometrical focusing. The hydrogen atomic beam intensity up to 1.0 A /cm2 (equivalent) was obtained in the Na-jet ionizer aperture of a 2.0 cm diameter. At the first stage of the experiment H− beam with 36 mA current, 5 keV energy and ~1.0 cm-mrad normalized emittance was obtained using the flat grids and magnetic focusing. The experimental results of the high-intensity neutral hydrogen beam generation and studies of the charge-exchange polarization processes of this intense beam will be presented.
	Slides FROAN3 [6.093 MB]
FROAN4	Femtosecond RF Gun Based MeV Electron Diffraction	2558
	J. Yang, K. Kan, Y. Murooka, N. Naruse, K. Tanimura, Y. Yoshida ISIR, Osaka, Japan J. Urakawa KEK, Ibaraki, Japan
	Ultrafast time-resolved electron diffraction based on a photocathode rf electron gun is being developed in Osaka University to reveal the hidden dynamics of intricate molecular and atomic processes in materials. A new structure rf gun has been developed to generates a low-emittance femtosecond-bunch electron beam, and has been used successfully for the single-shot MeV electron diffraction measurement. The transverse emittance, bunch length and energy spread were measured. The growths of the emittance, bunch length and energy spread due to the rf and the space charge effects in the rf gun were investigated by changing the laser injection phase, the laser pulse width and the bunch charge. The same demonstrations of the electron diffraction measurement were reported.
	Slides FROAN4 [5.097 MB]