FRIB Operators

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E-Bends

The E-Bends consist of two pairs of electrostatic plates with each plate having its own separate power supply.
The E-bends are responsible for bending the beam by 90 degrees two times.
- First bend: beam goes from ULEBT section down into the VLEBT section.
- Second bend: beam goes from the VLEBT section and into the linac tunnel.
The plates of the E-Bends are inside the beam line.
- In each pair, one plate is called the 'inner' plate while the other is called 'outer' plate. This is because the beam is bent in a circular fashion. So, one plate is near the inner radius of the bend while the other is near the outer radius.
The E-Bends serve as beam inhibit devices as they ultimately determine whether or not beam can be sent into the linac tunnel to be accelerated.
The plates are individually connected to a HV relay that prevents the plates from being charged from beam impact when the E-Bends' power supplies are turned off. These relays provide grounding; no charge accumulation can occur from beam impact on the plates that would otherwise cause inadvertent beam deflection into the linac tunnel.
Since the E-Bends act as beam inhibit devices, their power supplies are tied to the PPS.
- The Linac RSS system of the PPS must be in 'Beam Permit' before the PPS will allow the E-Bends' power supplies to be turned on.
- If 'Beam Permit' is lost while the E-Bends are on, the PPS will quickly ground each of the plates and turn off their power supplies.

The E-Bends are located at the top and bottom of the VLEBT section of the beamline.