Minutes -- Mucool meeting -- 11 Feb '00 Scribe: Dave Carey S. Geer _______ What are colling needs and how do we meet those need ? Table of potential cooling channel problems and corresponding experimental tests discussed last time, and in the minutes of the meeting last week. Updated table presented this week. Whre are we with defining the beam tests ? Need to resolve: 1) Do we need a precise scattering experiment. 2) What parameters is a cooling channel sensitive to (what do we have to measure and with what precision ?) Listed current mucool R&D projects. -- What can be pushed and what can't 1) RF development 2) Absorber development Push on design studies, plan beam test. 3) Prelim. Engineering design -- Ed Black plus initial cost estimate. 4) Initial cooling experiment Must understand what we have to measure -- including scattering and straggling. Need to know impact of errors on cooling. Alvin has just produced nice note. 5) Cooling channel beam test Need cooling design that works -- need to know sensitivities to errors. Is cooling essential for neutrino factory. Discussion on the need to determine the precise absorber dimensions before the test beam is built and tested. Greg Penn at LBL ________________ Simulation activity. Focus on phase rotation in induction linac. Get .03 muons per proton. Emittance is pretty close to target emittance. Define target emittance as hard cut at 3*sigma. Mary Anne Cummings __________________ LH2 absorber tests at FNAL. Bob Trendler is setting up safety review. No hard plan for absorber. Problem factorizes -- can work on several things simultaneously. 1) Windows and pressure test 2) Absorber assembly 3) Cryo plumbing and refrigeration 4) Pressure and temperature measurements Presented budget, which was in color and landscaped. Total cost with magnets $1,382,481 Total cost without magnets 582,481 Absorber assembly includes large window. Showed picture of absorber. Discussion about cost of refrigeration. Ed Black ________ Last week active with new FOFO. Put drawings on web. Showed first stage DFOFO cooling channel lattice. Flanges on each end of vessel don't fit. Trouble with disassembly. Volume of 6 gallons. Assume we we have to move volume --> 2.5 liters/sec. Need more than one nozzle to facilitate movement of liquid. Discussion about heat dissipation. Showed picture of EFOFO lattice. Gigantic 2.7 meter diameter vacuum chamber. Chun-Xi Wang ____________ Cooling formulae. Second moments for cylindrical symmetric beam. Moments significantly simplified. Reduces number of variables from ten to four. Derive moment equations. Parameterize beam moments. Similar to Twiss parameters. Everything consistent with well-known parameterization -- e.g. beta*gamma = 1 + alpha**2. Greg worked with = epsilon_{n}*beta_{perp}, similarity with Twiss parameters. Beta_{perp} is different with angular momentum. Beta is still for single particles. Can get equation governing evolution of envelope. Derive equations for emittance and angular momentum. Many ways to solve it. First-order homogenous equation. Solutions are described. Considers equilibrium emittance and equilibrium angular momentum. Want to minimize both. Shows plots of four curves 1) ICOOL 2) DPGEANT 3) ICOLL without correlation between amplitude and energy. 4) Analytical formulae (within 10% of simulation) Showed cases of transverse cooling factor for different channels using simulations vs. analytical formulae. Jim Norem _________ Phase II mu-cool experiment: Must make assumptions. Want to have a high power beam line ASAP. Requirements for coolings. Showed diagram for high-power facility. Momentum analyzed beam going into absorber. Has been using Penn's formalism. Beta functions between Penn and ICOOL do not agree. Start with alternating solenoid lattice for p about 120 MeV/c. Assume rf frequency is 805 MHz. Can get a lot of numbers with lattice. Described what can we do with this setup. Listed advantages of lower momentum.