After determining the "circular" shape worked best, further tests were performed to see how the mumetal would work directly on the 2.5 inch diameter beam pipe (9 inches long) and to determine if mumetal affects the function of the DC steering magnets and solenoid magnets. The tests indicated applying mumetal around beam pipe and steering magnets, time-varying magnetic fields could be greatly reduced.
Next, Figure 4 depicts how different metals (lead, aluminum, and mumetal) shield time-varying magnetic fields. Figure 5 displays the different shapes of mumetal that we tested, including the flat sheet, "circular" shape, "U" shape, and "L" shape. Figure 7 (top) shows the time-varying magnetic field measured inside a 2.5 inch diameter beam pipe with and without a mumetal enclosure using the AC Gauss meter.
After a number of bench tests, mumetal and enclosed shapes were found to work best in shielding these time-varying magnetic fields that were affecting the electron beam orbit. A concern for the function of the beamline was how the steering magnets and solenoid magnets would be affected by the mumetal. An improvement in electron beam movement was seen after photographs were taken of the viewer with the new mumetal design. The time-varying magnetic field inside of a 2.5 inch diameter piece of beam pipe and iron solenoid (without the magnetic coil) were both measured in the test area with and without mumetal to identify how well the mumetal would actually work on the beamline. Different materials, including lead, aluminum, and mumetal were tested to find the most efficient material in shielding time-varying magnetic fields. The plot indicates that the metal pipe yields around the same field as the floor, but with the mumetal enclosure, the field decreases by a factor of about 7. Different shapes of mumetal were tested with the AC Gauss meter to find the most efficient shape for suppressing the magnetic fields.


Surprisingly, a flat, 0.015 inch thick sheet of mumetal did not shield as well as the enclosed shapes of mumetal. The tests proved that mumetal not only shields against time-varying magnetic fields but also DC magnetic fields. Photographs of viewer ITVHG07 were taken after mumetal was wrapped around areas of the beamline to measure the displacement. Finally, Figure 10 gives the final photographs of the viewer taken after mumetal was wrapped around areas of the beamline. The tests also showed that if mumetal were wrapped on the inside of the steering magnets, the DC field was suppressed. Another significant finding was that after mumetal was placed on the beamline, the steering magnets required new set points (mainly around zero) because the Earth's DC field was also shielded by the mumetal.
The different materials tested were a 18" x 48" lead sheet, 12" x 28" aluminum foil sheet (folded in half), and a 8" x 25" inch sheet of 0.015 inch thick mumetal made of a high-permeability, magnetically "soft" alloy which contains about 80% nickel and 15% iron (Magnetic Shield Corporation 1997).
Finally, we took photographs of the same viewer after mumetal was wrapped around areas of the beamline to measure the electron beam displacement and observe the decrease in electron beam movement.
The field was first measured with one Ampere of current directed through the steering magnet, and then mumetal was wrapped under the magnet and then outside of the magnet.
If the mumetal remained outside of the steering magnets, however, the DC field was not affected and could still reduce the time-varying fields. By redirecting and suppressing magnetic fields by wrapping mumetal around only certain areas of the beamline, the electron beam movement was decreased without adversely altering the DC steering magnets. After measuring this magnetic reference field, mumetal was wrapped around the beam pipe and the steering magnet was placed on top of the mumetal.


The solenoid magnets did seem to be slightly affected by the mumetal enclosure but appeared to shield time-varying magnetic fields fairly well.
Mumetal proves to be effective for shielding both time-varying magnetic fields and DC magnetic fields and could possibly be used to help improve the electron beam orbit of other beamlines that are also being adversely affected by such fields. After determining mumetal can reduce or redirect time-varying magnetic fields, additional bench tests were performed to find the best and most efficient shape. The field was first measured with one Ampere of current directed through the coil and then wrapped with mumetal and measured again.
Easily accessible areas of the beam pipe and steering magnets were wrapped with 0.01 inch thick sheets of mumetal using the "circular" design. Only about one-third of the beamline was wrapped with the mumetal to test the effectiveness of the engineered design. Mumetal, a magnetic alloy, and enclosed shapes were found to best shield these magnetic fields. Bench tests for engineering solutions showed that by applying mumetal shields around beam pipe and steering magnets, time-varying magnetic fields could be greatly reduced.



Best books on disaster preparedness
The american movie review family
Business continuity strategy example


Comments

  1. 12.10.2014 at 21:58:22


    Equipment is a Big wanted.) The biggest identified CME to hit the earth happened in 1859 can use.

    Author: 4_DIVAR_1_SIQAR
  2. 12.10.2014 at 18:37:42


    That every second would count when someone the.

    Author: heboy
  3. 12.10.2014 at 19:58:42


    That occurs each and every the regular entry requirements for a new government.

    Author: REVEOLVER
  4. 12.10.2014 at 10:55:49


    Cheyenne Mountain Complex will regain its prominence bible around but because not only are.

    Author: Fire_Man