| Magnet Unit(s) | PR02 3149 |
|---|---|
| Typical BDES | 11.930 kG |
| Typical Current | 50 A |
| Typical PS Voltage | 20 V |
| Nominal Beta X | 38 m |
| Nominal Eta X | -0.60 m |
| Nominal Beta Y | 1.9 m |
| Nominal Eta Y | -0.012 m |
LER QFBM1 is one of a family of six quadrupole magnets (QDBM6,QFBM5,QFBM4, QDBM3,QFBM2, and QFBM1) early in straight two which match the optics from the exit of arc 3 into straight 2.
There is a set of these magnets at the entrance to IR2 (just after arc 3) and at the exit of IR2 (just before arc 1). These magnets live in the horizontal bending region close to the arcs.The LER IR2 lattice is complicated tremendously by the need to simultaneously deflect the beam down vertically to overlap the HER vertically, bend the beam horizontally to accommodate the horizontal IP separation scheme, taylor the beta functions at local sextupoles to cancel IP focusing chromaticity, achieve skew quadrupole cancellations of the rotations caused by off axis trajectory in the BaBar solenoid, and implement the strong focusing necessary to achieve small IP beta functions.
These magnets set the beta and eta functions at the entrance to the CCY/CCX section of LER IR2, just before the first vertical bend.