THOBN —  Advanced Concepts and Future Directions III   (31-Mar-11   10:00—12:00)
Chair: P. Muggli, USC, Los Angeles, California, USA

Paper	Title	Page
THOBN1	R&D Toward a Neutrino Factory and Muon Collider	2056
	M.S. Zisman LBNL, Berkeley, California, USA
	Funding: Work supported by U.S. Dept. of Energy, Office of High Energy Physics, under Contract No. DE-AC02-05CH11231. Significant progress has been made in recent years in R&D towards a neutrino factory and muon collider. The U.S. Muon Accelerator Program (MAP) has been formed recently to expedite the R&D efforts. This talk will review the US MAP R&D programs for a neutrino factory and muon collider. Muon ionization cooling research is the key element of the program. The first muon ionization cooling demonstration experiment, MICE (Muon Ionization Cooling Experiment) is under construction now at RAL (Rutherford Appleton Laboratory) in UK. Status of MICE as well as the U.S. contribution to MICE will be presented.
	Slides THOBN1 [1.987 MB]
THOBN2	Muon Collider Final Cooling in 30-50 T Solenoids	2061
	R. B. Palmer, R.C. Fernow BNL, Upton, Long Island, New York, USA J.L. Lederman UCLA, Los Angeles, California, USA
	Muon ionization cooling to the required transverse emittance of 25 microns can be achieved with liquid hydrogen in high field solenoids, provided that the momenta are low enough. At low momenta, the longitudinal emittance rises because of the negative slope of energy loss versus energy. Assuming initial emittances that have been achieved in six dimensional cooling simulations, optimized designs are given using solenoid fields limited to 30, 40, and 50 T. The required final emittances are achieved for the two higher field cases.
	Slides THOBN2 [0.319 MB]
THOBN3	Proof-of-Principle Experiment for FEL-based Coherent Electron Cooling	2064
	V. Litvinenko, I. Ben-Zvi, J. Bengtsson, A.V. Fedotov, Y. Hao, D. Kayran, G.J. Mahler, W. Meng, T. Roser, B. Sheehy, R. Than, J.E. Tuozzolo, G. Wang, S.D. Webb, V. Yakimenko BNL, Upton, Long Island, New York, USA G.I. Bell, D.L. Bruhwiler, B.T. Schwartz Tech-X, Boulder, Colorado, USA A. Hutton, G.A. Krafft, M. Poelker, R.A. Rimmer JLAB, Newport News, Virginia, USA
	Funding: This work is supported the U.S. Department of Energy Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, high-intensity hadron-hadron and electron-hadron colliders*. In a CEC system, a hadron beam interacts with a cooling electron beam. A perturbation of the electron density caused by ions is amplified and fed back to the ions to reduce the energy spread and the emittance of the ion beam. To demonstrate the feasibility of CEC we propose a proof-of-principle experiment at RHIC using one of JLab’s SRF cryo-modules. In this paper, we describe the experimental setup for CeC installed into one of RHIC's interaction regions. We present results of analytical estimates and results of initial simulations of cooling a gold-ion beam at 40 GeV/u energy via CeC. * Vladimir N. Litvinenko, Yaroslav S. Derbenev, Physical Review Letters 102, 114801
	Slides THOBN3 [1.379 MB]
THOBN4	Experiment to Demonstrate Acceleration in Optical Photonic Bandgap Structures	2067
	R.J. England, E.R. Colby, R. Laouar, C. McGuinness, D. Mendez, C.-K. Ng, J.S.T. Ng, R.J. Noble, K. Soong, J.E. Spencer, D.R. Walz, Z. Wu, D. Xu SLAC, Menlo Park, California, USA E.A. Peralta Stanford University, Stanford, California, USA
	Funding: This work was funded by Department of Energy Grants DE-AC02-76SF00515, DE-FG06-97ER41276. Optical scale dielectric structures offer a promising medium for high-gradient, compact, low-cost acceleration of charged particles. An experimental program is underway at the SLAC E163 facility to demonstrate acceleration in photonic bandgap structures driven by short laser pulses. We present initial experimental results, discuss structure and experimental design, and present first estimates of achievable gradient.
	Slides THOBN4 [5.925 MB]
THOBN5	Design and Testing of Advanced Photonic Bandgap (PBG) Accelerator Structures	2071
	B.J. Munroe, M.A. Shapiro, R.J. Temkin MIT/PSFC, Cambridge, Massachusetts, USA V.A. Dolgashev, S.G. Tantawi, A.D. Yeremian SLAC, Menlo Park, California, USA R.A. Marsh LLNL, Livermore, California, USA
	Photonic Band-gap (PBG) structures continue to be an area of promising research for high gradient accelerators with wakefield suppression. Experimental results on an 11.4 GHz PBG structure tested at high power and high repetition rate at SLAC have shown that high gradients can be achieved in these structures. For PBG structures with thin rods, however, pulsed heating of the inner row of rods is a problem. Following these preliminary results, two new PBG structures have been designed. One structure, designated 1C-SW-A5.65-T4.6-Cu-PBG2-SLAC1, utilizes elliptical inner rods to reduce pulsed heating to an acceptable level; it will be tested at SLAC. A second PBG structure with round rods will be tested at 17.1 GHz at MIT. The MIT research will use the improved diagnostic access of the PBG structure to obtain a better understanding of the breakdown process. We will present preliminary results for the design and testing of these PBG structures.
	Slides THOBN5 [0.752 MB]
THOBN6	Wakefield Breakdown Test of a Diamond-Loaded Accelerating Structure	2074
	S.P. Antipov, C.-J. Jing, A. Kanareykin, P. Schoessow Euclid TechLabs, LLC, Solon, Ohio, USA M.E. Conde, D.S. Doran, W. Gai, J.G. Power, Z.M. Yusof ANL, Argonne, USA
	Funding: DOE SBIR Diamond has been proposed as a dielectric material for dielectric loaded accelerating (DLA) structures. It has a very low microwave loss tangent, the highest available thermoconductive coefficient and high RF breakdown field. In this paper we report the results from a wakefield breakdown test of diamond-loaded rectangular accelerating structure and development of a cylindrical diamond DLA. We expect to achieve field levels on the order of 100 MV/m in the structure using the 100nC beam at the Argonne Wakefield Accelerator Facility. Single crystal diamond plates produced by chemical vapor deposition (CVD) are used in the structure. The structure is designed to yield up to 0.5 GV/m fields on the diamond surface to test it for breakdown. A surface analysis of the diamond is performed before and after the beam test.
	Slides THOBN6 [1.629 MB]