| Magnet Unit(s) | PR02 4052 |
|---|---|
| Typical BDES | -13.101 kG |
| Typical Current | 50 A |
| Typical PS Voltage | 20 V |
| Nominal Beta X | 3.7 m |
| Nominal Eta X | 0.29 m |
| Nominal Beta Y | 29 m |
| Nominal Eta Y | 0.02 m |
LER QDS4 is one of a family of arc magnets (QFS5,QDS4,QFS3,QDS2,QFS1) which are used to match the dispersion at the end of arc 3 adjacent to straight 2. These magnets are sometimes called "dispersion suppressors".
There is a set of these magnets at the end of arc 3 (the last 5 arc 3 quadrupoles) and at the beginning of arc 1 (the first 5 arc 1 quadrupoles).Unlike the similar dispersion suppressors adjacent to straights 4 and 12, these magnets are each powered individually. This is to allow compensation for the BaBar solenoid using arc magnets.