• W. Chou, A.I. Drozhdin, C. Hill, M.A. Kostin, J.-F. Ostiguy, Z. Tang
  Fermilab, Batavia, Illinois
• H.C. Bryant
  UNM, Albuquerque, New Mexico
• R.J. Macek
  LANL, Los Alamos, New Mexico
• G. Rees
  CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
• P.S. Yoon
  Rochester University, Rochester, New York

Fermilab is working on the design of an 8 GeV superconducting RF H^- linac called the Proton Driver. The energy of the H^- beam is an order of magnitude higher than any existing H^- beams. This brings up a number of new challenges to the transport, stripping and injection into the next machine (the Main Injector), such as blackbody radiation stripping, magnetic field and residual gas stripping, Stark states of hydrogen atoms, foil stripping efficiency, single and multiple Coulomb scattering, energy deposition, foil heating and stress, radiation activation, collimation, jitter correction, etc. This paper will give a summary of these studies.*

*For details the reader is referred to FERMILAB-TM-2285-AD-T.

• L. Michelotti, J.-F. Ostiguy
  Fermilab, Batavia, Illinois

We introduce CHEF, a program built on a "Collaborative Hierarchical Exploratory Framework" for doing optical calculations in accelerator physics. CHEF organizes and shares information between independent components that employ graphical user interfaces for interactive use. Among them are: a browser to display the beamline model's structure; a site viewer to show a line's geometry; phase space windows to oversee development of tracking calculations; a trace window to display the passage of a probe particle through beam position monitors; a plotter for displaying optical functions; a parser which constructs beamline models defined in MAD8 format and allows for interactive editing and debugging of the lattice files. Calculations are carried out by a hierarchy of C++ class libraries, most notably: MXYZPTLK handles automatic differentiation and differential algebra; BEAMLINE contains classes for modeling accelerator components; PHYSICS_TOOLKIT encapsulates specific calculations. Python bindings to these libraries and to CHEF's components, in conjunction with an embedded interpreter, provide a mechanism to extend and customize CHEF's functionality.

• J.-F. Ostiguy, M. Kriss, M. McCusker-Whiting, L. Michelotti
  Fermilab, Batavia, Illinois

Fermilab is a large accelerator complex with six rings and sixteen transfer beamlines operating in various modes and configurations, subject to modifications, improvements and occasional major redesign. Over the years, it became increasingly obvious that a centralized lattice repository with the ability to track revisions would be of great value. To that end, we evaluated potentially suitable revision systems, either freely available or commercial, and decided that expecting infrequent users to become fully conversant with complex revision system software was neither realistic nor practical. In this paper, we discuss technical aspects of the recently introduced FNAL Accelerator Division's Lattice Repository, whose fully web-based interface hides the complexity of Subversion, a comprehensive open source revision system. In particular we emphasize how the architecture of Subversion was a key ingredient in the technical success of the repository's implementation.