| Magnet Unit(s) | PR02 3018 |
|---|---|
| Typical BDES | < 1.88 kG |
| Typical Current | 200 A |
| Typical PS Voltage | 12 V |
| Nominal Beta X | 10 m |
| Nominal Eta X | -0.058 m |
| Nominal Beta Y | 130 m |
| Nominal Eta Y | -0.002 m |
LER QD1R TRIM one of three electrical circuits which augment the field of the IP QD1 permanent magnets. The three electrical circuits are QUAD, XCOR, and YCOR. The XCOR/YCOR have a 50 amp range, and the QUAD has a 250 amp range.
The purpose of the QD1 trim QUAD is twofold. First, it allows adjustablility of the overall QD1 strength (by a few percent) which is useful if it is desired to change the energy of the LER beam. Such would be done if for instance PEPII were to choose to run on the epsilon 5S resonance rather than the nominal design epsilon 4S resonance. Second, the QUAD TRIM is used to compensate the matter that the BaBar solenoid, in which whose field the QD1 magnets are immersed, is not uniform for the two QD1 magnets. The non-uniformity of the BaBar solenoid stems from the geometry of the BaBar flux return which is not symetric on the forward vs. backward side.