CERN Accelerating science

Article
Title	Beam-Based Alignment in the RHIC eCooling Solenoids
Author(s)	Cameron, Peter ; Ben-Zvi, Ilan ; Dawson, William C ; Kewisch, Jorg ; Litvinenko, Vladimir N ; Luo, Yun ; MacKay, William W ; Montag, Christoph ; Niedziela, Jennifer ; Ptitsyn, Vadim ; Satogata, Todd ; Schultheiss, Carl ; Yakimenko, Vitaly
Affiliation	(BNL, Upton, Long Island, New York)
Publication	2005
In:	21st IEEE Particle Accelerator Conference, Knoxville, TN, USA, 16 - 20 May 2005, pp.2771
Subject category	Accelerators and Storage Rings
Abstract	Accurate alignment of the electron and ion beams in the RHIC electron cooling solenoids is crucial for well-optimized cooling. Because of the greatly differing rigidities of the electron and ion beams, to achieve the specified alignment accuracy it is required that transverse magnetic fields resulting from imperfections in solenoid fabrication be down by five orders of magnitude relative to the pure solenoid fields. Shimming the solenoid field to this accuracy might be accomplished by survey techniques prior to operation with beam, or by methods of beam-based alignment. We report on the details of a method of beam-based alignment, as well as the results of preliminary measurements with the ion beam at RHIC