1 / 15

IPNS Third RF Cavity Status Report

Overview of IPNS accelerator facility delivering intense proton pulses to produce neutrons. Details on history, ion source, linac, RCS, and beamline operations. Future plans for third RF station.

schrum
Download Presentation

IPNS Third RF Cavity Status Report

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. IPNS Third RF Cavity Status Report G.E. McMichael Accelerator Facilities Manager Presentation at the Ninth SHRF/LOIA Collaboration Meeting June 14, 2004

  2. IPNS ACCELERATOR OVERVIEW • Accelerator delivers a short (70 ns) intense (3 x 1012 protons/pulse) pulse of 450 MeV protons to the depleted-uranium target 30 times per second • Each proton produces about 15 neutrons • IPNS is a user facility. Sole purpose of the accelerator is to produce neutrons (99% for the neutron-scattering instruments in Bldg. 375, remainder for an “exotic-beam” source for ATLAS)

  3. IPNS ACCELERATOR FACILITY • Three accelerators in series • 750 keV Preaccelerator • 50 MeV Linac • 450 MeV Rapid Cycling Synchrotron (RCS) • Ancillary Systems • RF (Variable Frequency Beam Feedback controlled) • Magnets and power supplies (Pulsed & DC) • Control, diagnostics and data acquisition • Vacuum • Safety (Personnel & Equipment) • Buildings and Utilities • AC Power • Water Systems • Air Conditioning

  4. HISTORY • Preaccelerator and linac entered service in 1961 as injector to the 12.5 GeV ZGS (Zero Gradient Synchrotron) high-energy physics accelerator • RCS developed in mid 1970's as a proposed booster for ZGS. Excess beam would have been available for a spallation neutron source • ZGS was shut down in 1979. RCS initially (1977-1980) provided beam into the ZING experimental target. First beam to IPNS target was in 1981 • Eight-billionth pulse 16 April, 2004

  5. ION SOURCE & PREACCELERATOR • Magnetron-type H- ion source, cesium getter • Extraction at 20 keV, magnet to separate electrons • Cockcroft-Walton generator, 750 Kv • Output H- beam, 30 mA peak, 70 µs pulses, 30 Hz

  6. LINAC • Alvarez-type “drift-tube linac” • Copper-clad steel tank, 33.5 m long, 0.93 m diameter • 124 drift tubes, each with a dc quadrupole magnet • 200 MHz rf transmitter, triode amplifier tube, 3.5 MW • Output H- beam 50 MeV, 10 mA peak, 70 µs pulses, 30 Hz

  7. 50 MEV TRANSPORTATION LINE • 8 Dipole horizontal bending magnets • 6 Dipole vertical steering magnets • 16 Quadrupole focusing magnets • 12 Wire scanners, 6 Beam position monitors • Transports H- beam ≈ 40 m from linac to RCS

  8. RAPID CYCLING SYNCHROTRON “ RCS” • 43 m circumference strong-focusing, combined-function synchrotron • 6-sector machine, magnet structure D00FDF0 • Betatron tune correction provided by two pairs of sextupole magnets • Multi-turn injection ( 130 turns, “3 mile string”) • Single-turn extraction by two ferrite-loaded kicker magnets and two septum magnets

  9. RAPID CYCLING SYNCHROTRON “ RCS” • Ring magnets are part of a biased 30 Hz resonant circuit. Generate a magnetic field that varies from 0.28 to 1 Tesla during the accelerating cycle • Thin carbon foil strips off the two electrons • Two rf cavities to bunch and accelerate the proton beam • Third rf cavity will be installed in L6 section • Output proton beam 450 MeV, 70-80 ns pulse, 30 Hz, 3 x 1012 protons/pulse

  10. PTS BEAMLINE • 4 Dipole horizontal bending magnets • 2 Dipole vertical steering magnets • 15 Quadrupole focusing magnets • 6 Segmented secondary emission monitors, 1 Segmented wire ion chamber • Transports H- beam ≈ 45 m from RCS to neutron-generating target

  11. ACCELERATOR OPERATIONS OPERATING PERIODS • Typically two to four weeks on and one to two weeks off • Six-hours reserved each Tuesday for machine research and moderator regeneration • Two longer shutdowns (Christmas and summer) for installations and larger maintenance jobs

  12. THIRD RF STATION • Cavity almost identical to two existing • Redesigned rf amplifier systems: • Pre-driven and final use new tubes • Driver is an updated version of existing systems • New low-level system • Provide second-harmonic rf for capture and initial acceleration • Provide additional fundamental at mid-cycle • Can function as on-line spare for existing fundamental systems • Installation to start in 6 months

  13. 2nd – HARMONIC RF • Propose to enhance 3rd rf system to operate at 2nd harmonicthroughout the acceleration cycle • Principal addition will be a new cavity with different ferrite • Funding and schedule uncertain

  14. SUMMARY • IPNS continues to have a moving 10-year window – to ensure reliable operation for the next 10 years • Recent budget problems have slowed the upgrade/assurance program. • Our interest in the collaboration remains strong - Shaoheng Wang will be joining our program

More Related