A close-up of the storage ring magnet. The blue part is the iron yoke of the magnet. The silver "boxes" running along the blue yoke steel are the cryostats which hold superconducting coils. The "L"-shaped vertical bar is the lifting rig which is attached on one of the magnet pole pieces. The amber end of the pole piece is kapton which insulates each pole piece from the adjacent pole piece. This prevents eddy currents from running around the pole pieces during a quench of the magnet. The champfer of the pole piece can be clearly seen.
A close up of the magnet with the vacuum chamber installed between the pole pieces. The high-voltage feedthrough for the electrostatic quadrupoles can be seen in the center-left of the picture. The notch in the vacuum chamber 2/3s of the way along from right to left is where the detector sits. The many tabs above and below the vacuum chamber are the adjusing screws and supports for the wedges used in shimming the magnet.
One of the three kicker modulators. A capacitor in the cylindrical section is charged to 100 kV through a resistor at the top of the "T." A thyratron in the section to the left of the red box is fired to short the capacitor to ground, thus producing the current pulse which kicks the muon beam.
The pion production target. The window which isolates it from the room has been removed. Ni disks on a spindle are rotated by the chain/sprocket arrangement which you see here. The beam pulse hits the disk at 9:00 o'clock. The disk then rotates into water, which is just below the window opening. This is a simple and effective way to remove the heat generated by the beam.
The pion decay-channel where the muons are born. It consists of quadrupole magnets, alternating in polarity.
The junction of two magnet pole pieces. You can see the kapton insulation, the edge of the champfer and the "pole bump" on the edge of the pole which helps shim out the effect of the edge of the pole piece.
Another view of the production target, showing the upstream instrumentation (red box) which monitors the beam hitting the target. The yellow object on the left is a thick steel "curtain" which can slide to the right, covering the production target and providing radiation shielding if personnel need access to this area.
Inside view of the production target.
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