| 5 | | The BPm operates by rotating a helical wire through the beam. The axis of rotation is 45^^o^^ to the horizontal plane of the beam. The wire rotates at 19 cycles per second. During one complet rotation the wire passes through the beam once horizontally and once vertically due to the shape of the wire. When the wire passes through the beam, secondary electrons are released and collected. The magnitude of the electron current. |
| | 5 | The BPM operates by rotating a helical wire through the beam. The axis of rotation is 45^^o^^ to the horizontal plane of the beam. The wire rotates at 19 cycles per second. During one complete rotation the wire passes through the beam once horizontally and once vertically due to the shape of the wire. When the wire passes through the beam, secondary electrons are released and collected. |
| | 6 | This electron current is measured as a function of time. By matching the corresponding signal within the timing of one rotation you can measure the electron current induced when the wire scans vertically and horizontally. The magnitude of the electron current is prortional to the magnitude of the beam current, hence giving us our vertical and horizonal profiles. |
