Monitoring the NuMI Primary Beam

   We are developing instrumentation to monitor the transport of the NuMI primary proton beam. NuMI extracts 120 GeV protons from the Main Injector and focuses these on a 1 meter graphite target to produce pions which decay to neutrinos. Along the way, the proton beam position and transverse size must be monitored to ensure proper beam transport.

Click on the pictures for an enlarged view
The photo is of the interior of one of our foil SEM's: the segmented foils are mounted at +-45 degrees on an open hexagonal frame that is actuated in-out on a 2" shaft through a bellows. The plots at right show the profiles of the NuMI beam on the 10th pulse extracted from the Main Injector Dec. 3, 2004. The beam made it all the way down to our absorber (although some scraping is evident on a couple of the profiles).

Documentation   

  • Specifications for our final NuMI SEM design.
  • Poster presented at "Beams Instrumentation Workshop '04" at Oak Ridge: paper, poster
  • Testbeam results from our prototype SEM: NIM article, NuMI-note
  • Design of our first prototype SEM (NuMI-B-933): pdf
  • Study of beam heating of SEM's: ps, pdf
  • Study of spring force of foil accordions: ps, pdf
  • Study of accuracy of LVDT measurements: ps, pdf

    Reviews, Progress Reports:   
    Following are several slide presentations made to other groups:

  • Presentation to the MI Department 12/10/04 describing our SEM.

    Following are several slide presentations culled from previous reviews and progress reports. These cover the following aspects of the SEM:

  • Results from our test beam conducted in the 8 GeV MiniBooNE transfer line.
  • Mounting of the foils on the paddle frame.
  • Motion actuator which drives the foils into or out of the beam.
  • Testing of the SEM under vacuum (out gas rates, ultimate pressure, RGA tests, etc).

    Below are internal NuMI project reviews on the SEM's:

  • Presentation at 10/24/03 review of NuMI Profile Monitor SEM's: pdf, ppt
  • Presentation at 10/14/02 review of conceptual design of NuMI Profile Monitor SEM's: pdf, ppt
  • Weekly status reports given to B.Baller and S.Childress.

      Links to Beam Instrumentation Groups.
    (other than our own!)

    Brookhaven National Laboratory CERN, Geneva, Switzerland
    Fermi National Accelerator Laboratory GSI, Germany