| Magnet Unit(s) | PR06 8044 |
|---|---|
| Typical BDES | < 7.0 kG |
| Typical Current | 50 A |
| Typical PS Voltage | <10 V |
| Nominal Beta X | 37 m |
| Nominal Eta X | 0 m |
| Nominal Beta Y | 8 m |
| Nominal Eta Y | 0.0 m |
SQG3 is one of a family of four global skew quads (SQG1 through SQG4) for the HER.
Skew quads introduce coupling or rotation. Like all quadrupoles, the (deflecting) field gradient is uniform across position in the quadrupole magnet's field. An upright quadrupole provides an X or Y deflection proportional to X or Y offset, with no Y deflection dependance upon X position and vice versa. A skew quadrupole (upright quadrupole rotated 45 degrees) provides X and Y deflection each of which varies with both X and Y offset.
HER has two families of skew quadrupoles: Global and IR2 local.
Global skew quadrupoles are intended to be used to tune away (cancel) unintended sources of coupling or rotation (upright quadrupole roll errors and nonzero vertical trajectory in sextupole magnets).
IR2 local skew quadrupoles are intended to be used to cancel beam rotation caused by the design off-axis and dispersive trajectory through the BaBar solenoid field.