Numbers of installed units:
MEBT: 5
DTL: 6
CCL: 8
SCL: 32
HEBT: 11
Responsible parties:
Analog electronics: Chris Rose and John Power, LANL.
Digital electronics: Matt Stettler, LANL.
MEBT & HEBT Pickups: Peter Cameron, BNL
DTL, CCL, SCL Pickups: Ross Meyer, LANL
Measurement:
The harp system provides a measurement of beam position and
profile.
Key specifications:
Scanning modes:
Fly mode and step mode. Step mode will average given number of beam
pulses per step.
Beam pulse length:
Limited by wire heating. At least 50 us ramped for DTL and CCL units,
at least 100 us ramped for SCL units.
Peak beam current range:
5 to 60 mA.
Position accuracy:
±2 mm when
data is fitted with a Gaussian profile.
Width accuracy: 10% when data is
fitted with a Gaussian profile.
Positioning accuracy of wire:
0.25 mm (consistent with beam box alignment accuracy).
Position read back accuracy: 0.25
mm.
Wire positioning rate:
5 Hz in step mode.
Bandwidth:
35 kHz (see note 1 below).
Number of signal wires:
3 (x, y, and x-y).
Signal wire bias:
~ 100 V dc, bi-polar.
Stroke:
All wires must scan entire beam pipe aperture. The fork and wire mounting
fixtures must never be in the beam pipe aperture.
Normalization
Using a nearby current monitor. Normalization performed by an EPICS
application or by a data concentrator.
Inputs:
Signal cables from wire scanner actuator.
Wire position readback.
RTDL/event link.
120 Vac (on/off control via control system).
Channel Access
Outputs:
Wire position control.
Channel Access.
Machine Protect if signal from wire exceeds threshold, to
prevent wire damage.
Delivery schedule:
DTL – Spring 2002.
CCL – Fall. 2002.
SCL – Spring 2003.