U.S. Particle Accelerator School

SNS II - Ring and Transport Systems course

Sponsoring University:

University of Wisconsin - Madison


SNS II - Ring and Transport Systems


Jie Wei, BNL and Yannis Papaphilippou, ESRF

The Spallation Neutron Source (SNS) is a new-generation, high-power accelerator complex that delivers a proton beam power above 1 MW for pulsed neutron applications. The complex consists of a H- ion source and front end, a superconducting RF linac, a full-energy accumulator ring, and a mercury target. The SNS accumulator ring and the transport lines are designed to handle a record intensity of 2 x 10^14 protons at a repetition rate of 60 Hz. This course is to introduce design principles and procedures, beam physics and technology for this high-intensity frontier machine. We will start with the design philosophy and the basic layout and functions of the ring and transport lines. Among beam dynamics subjects are machine lattice design and aperture selection, beam loss mechanisms, single-particle topics including kinematic nonlinearity, sextupole effects, magnetic imperfection and nonlinearity, magnet fringe field, resonance analysis, dynamic apertures, and multi-particle topics including space charge, coupling impedance, instabilities, and electron-cloud effects. Among accelerator system subjects are magnet, power-supply, vacuum, injection, extraction, collimation, RF, and diagnostics. Finally, we will review basic beam commissioning procedures. Prerequisites: Accelerator Fundamentals or Accelerator Physics course. Textbook to be provided: "AIP Conference Proceeding 642 High Intensity and High Brightness Hadron Beams: 20th ICFA Advanced Beam Dynamics Workshop on High Intensity and High Brightness Hadron Beams" edited by Chou et al, Springer publishers.