COLLECTION OPTICS WITH THE HORN TYPE FOCUCING ELMENT MADE WITH SEPARATE CONDUCTORS
We describe the device for focusing of charged particles by the system of separated conductors which follow the parabolic profile. Basically this is a horn-type focuser, but with the individual conductors instead of continuous surface. This device allows substantial reduction of fabrication cost with the same focusing properties as the continuous parabolic surface. We recommend this “bird-cage” type system for focusing pions/muons in the projects under discussion in many Laboratories around the World. OVERVIEW Necessity for good quality secondary beams is well argumented topic for the high energy physics [1]-[3]. The horn-like focusing elements (lenses) are broadly in use in many laboratories for collection of secondary particles in the proton lines. One example of usage of miniature copy of such lens for collection of positrons is known from Budker INP [4]. For collection of pions the horns reach sized of ~0.5 m in diameter and ~2 m long [5]. Fabrication of thin wall parabolic surface of this scale represents substantional technological difficulties. Typically it is fabricated from solid billets of 40-6061-T6 Aluminum with typical lengths of 40 cm [5]. Three segments are electron beam welded together. Typical thickness of the parabolic wall is around 2mm. In all horn-like focusing devises the secondary beams running through material of paraboloid. In this publication we made a proposition to approximate continuous surface of paraboloid with limited number of separate conductors. This approach delivers significant simplifications in technology of fabrication. The payoff for this-a distortions of trajectories can be made acceptable as the angular spread of secondary beams is significant. Any way it is comparable with divergences obtained as a result of multiple scattering in material of paraboloid.
Project X: A Multi-MW Proton Source at Fermilab
As the Fermilab Tevatron Collider program draws to a close a strategy has emerged of an experimental program built around the high intensity frontier. The centerpiece of this program is a superconducting H- linac that will support world leading programs in long baseline neutrino experimentation and he study of rare processes. Based on technology shared with the International Linear Collider (ILC), Project X will provide multi-MW beams at 60-120 GeV from the Main Injector, simultaneous with very high intensity beams at lower energies. Project X will also support development of a Muon Collider as a uture facility at the energy frontier.
Mathematical Modeling of Scour and Deposition
Electronic computers are opening up the field of sedimentation engineering by permitting the analysis of problems which heretofore have required too much time and effort. Movable stream bed profiles are being calculated in addition to water surface profiles. The initial gradation of sediment material in the stream bed may be prescribed to facilitate the calculation of an armor layer. This gradation is continually changed by the computer program in response to sediment particles being deposited on the stream bed and material on the stream bed being removed to satisfy transport capacity. Hydraulic sorting of sediment by grain size is accomodated. The stream bed does not have to be represented by a single grain size. Retardance of motion because of armor layer is calculated.