TY  - JOUR
AU  - Marco-Hernandez, R.
AU  - Bau, M.
AU  - Ferrari, M.
AU  - Ferrari, V.
AU  - Pedersen, F.
AU  - Soby, L.
PY  - 2017
DA  - 2017//
TI  - A Low-Noise Charge Amplifier for the ELENA Trajectory, Orbit, and Intensity Measurement System
T2  - IEEE Trans. Nucl. Sci.
JO  - IEEE Transactions on Nuclear Science
SP  - 2465
EP  - 2473
VL  - 64
IS  - 9
PB  - Ieee-Inst Electrical Electronics Engineers Inc
KW  - Beam position monitor (BPM)
KW  - charge sensitive amplifier
KW  - instrumentation for accelerators
KW  - low-noise amplifier
KW  - particle accelerators
KW  - printed circuits
AB  - A low-noise head amplifier has been developed for the extra low energy antiproton ring beam trajectory, orbit, and intensity measurement system at CERN. This system is based on 24 double-electrode electrostatic beam position monitors installed around the ring. A head amplifier is placed close to each beam position monitor to amplify the electrode signals and generate a difference and a sum signal. These signals are sent to the digital acquisition system, about 50 m away from the ring, where they are digitized and further processed. The beam position can be measured by dividing the difference signal by the sum signal while the sum signal gives information relative to the beam intensity. The head amplifier consists of two discrete charge preamplifiers with junction field effect transistor (JFET) inputs, a sum and a difference stage, and two cable drivers. Special attention has been paid to the amplifier printed circuit board design to minimize the parasitic capacitances and inductances at the charge amplifier stages to meet the gain and noise requirements. The measurements carried out on the head amplifier showed a gain of 40.5 and 46.5 dB for the sum and difference outputs with a bandwidth from 200 Hz to 75 MHz and an input voltage noise density lower than 400 pV/v Hz. Twenty head amplifiers have been already installed in the ring and they have been used to detect the first beam signals during the first commissioning stage in November 2016.
SN  - 0018-9499
UR  - https://doi.org/10.1109/TNS.2017.2740238
DO  - 10.1109/TNS.2017.2740238
LA  - English
N1  - WOS:000411029500002
ID  - Marco-Hernandez_etal2017
ER  -