The Neutrino Factory and Muon Collider Collaboration A HIGH-FIELD PULSED SOLENOID MAGNET FO.pdfVIP

The Neutrino Factory and Muon Collider Collaboration A HIGH-FIELD PULSED SOLENOID MAGNET FOR LIQUID METAL TARGET STUDIES H.G. Kirk1, M. Iarocci, J. Scaduto, R.J. Weggel BNL, Upton, NY 11973, USA G. Mulholland Applied Cryogenics Technology, Ovilla, TX 75154, USA P. Titus MIT, Cambridge, MA 02139, USA K.T. McDonald Princeton University, Princeton, NJ 08544, USA ABSTRACT The target system for a muon collider/neutrino factory requires the conjunction of an intense proton beam, a high-Z liquid target and a high-field solenoid magnet. We describe here the design parameters for a pulsed solenoid, including the magnet cryogenic system and power supply, that can generate transient fields of greater than 10T with a flat-tops on the order of 1 second. It is envisioned to locate this device at the Brookhaven AGS for proof- of-principle testing of a liquid-jet target system with pulses of 1e13 protons. Harold G. Kirk PAC 2003, May 13, 2003 1 The Neutrino Factory and Muon Collider Collaboration 1 THE TARGETRY CONCEPT A muon collider or a neutrino factory based on a muon storage ring [1] require intense beams of muons, which are obtained from the decay of pions produced in proton-nucleus collisions. To max- imize the yield, pions of momentum near 300 MeV/c should be captured. For proton energies above 10 GeV, the pion yield per unit of proton beam energy is larger for a high-Z target. For pro- ton beam energies in the MW range, beam heating would melt or crack a stationary high-Z target, so a moving target must be used. A mercury jet target is the main focus of BNL E951 [2], although RD is also being conducted on a carbon target option as might be suitable for a low-energy proton source, and conceptual studies have been carried out for rotating-band targets, a tantalum/water target, and a liquid-lithium target. The low-energy pions are produced with relatively large angles to the proton beam, and efficient capture into a decay and phase- rotation channel is obtained by surrounding