Alpha Helium-3 Protons Deuterons particles ions ------- --------- --------- -------- Maximum energy (Mev) 730 460 910 1140 Energy spread (Mev) 55 Beam intensity Average current ([mu]a) 0.75 0.75 0.25 Peak current ([mu]a) 120 120 40 Beam radius, maximum (in.) 82 82 82 82 Time required for acceleration (msec) 6 4.5 4.5 Number of revolutions during acceleration 75,000 60,000 60,000 Distance traveled during acceleration (miles) 450 360 360 Velocity at maximum energy (% of speed of light) 82 60 60 69 Mass increase at maximum energy (% of rest mass) 75 25 25 40 Range of full-energy particles (in. of aluminum) 37 12 7 _External Beams_ Physics cave Meson cave ----------------------- ------------------- Protons Neutrons [pi]^+ [pi]^+ [pi]^- ------- -------- ------ -------- --------- Energy (Mev) 730 310 100|250 100| 300 Energy spread (Mev) 14 10| 20 10| 30 Beam area (cm^2) 25 40 100|100 100| 100 Flux (particles/cm^2-sec) 2×10^10 5×10^5 5×10^4 1000|100 1500|1000 _Acceleration chamber (vacuum tank)_ Size length (ft) 25 width (ft) 20 height (ft) 4 Material: mild steel Operating pressure (mm Hg) 10^-5 Vacuum pumps: six 20-in. oil-diffusion pumps with 8-in. boosters: one Beach-Russ 750-cfm; one Kinney 300-cfm; two Kinney 105-cfm. Pumping speed of oil-diffusion pumps (liters/sec) 20,000 _Magnet_