The QPweak Spectrometer:
| The QPweak spectrometer is an eight-sector, water cooled, toroidal magnet with eight 4.3 meter long and 1.5 meter wide racetrack copper coils. Each coil weighs about 3300 kg. The maximum operating current for the spectrometer is 9500 Amperes, requiring 1.5 MW of power. The normal operating current when running with liquid hydrogen is 8921 Amperes. | Attach:Spectrometer.jpg Δ |
The purpose of the spectrometer is to focus those electrons that are elastically scattered at the desired angles (as selected by a set of collimators) onto the main electron detectors. In doing so, the spectrometer also steers away electrons (and other charged particles) with the wrong energy (i.e inelastically scattered electrons), so that they don't hit the detectors, which reduces what we refer to as background.