Design and performance of a high resolution, low latency stripline beam position monitor system

Abstract

A high-resolution, low-latency beam position monitor (BPM) system has been developed for use in particle accelerators and beam lines that operate with trains of particle bunches with bunch separations as low as several tens of nanoseconds, such as future linear electron-positron colliders and free-electron lasers. The system was tested with electron beams in the extraction line of the Accelerator Test Facility at the High Energy Accelerator Research Organization (KEK) in Japan. It consists of three stripline BPMs instrumented with analogue signal-processing electronics and a custom digitizer for logging the data. The design of the analogue processor units is presented in detail, along with measurements of the system performance. The processor latency is 15.6 AE 0.1 ns. A single-pass beam position resolution of 291 AE 10 nm has been achieved, using a beam with a bunch charge of approximately 1 nC.

Design and operation of a prototype interaction point beam collision feedback system for the International Linear Collider

“…The FONT stripline BPMs (Fig. 9) each consist of four 12-cm-long strips, arranged as two orthogonal diametrically opposed pairs separated by 23.9 mm [22]. BPMs P1, P2 and P3 are each mounted on a M-MVN80 and M-ILS50CCL Newport mover system [23] that can translate the BPM vertically and horizontally in the plane perpendicular to the beam, allowing the beam to be centered within each BPM aperture.…”

A high-resolution, low-latency, bunch-by-bunch feedback system for nano-beam stabilization

“…The stripline kicker (Fig. 13) is a modified stripline BPM [9] and consists of two conducting strips, ∼12.5 cm in length and separated by 24 mm, at the top and bottom of the inside of the beam-pipe. The custommade kicker amplifier (see eg.…”

“…group [8] has developed several generations of prototype bunch-by-bunch beam-stabilization feedback systems which have been tested at the ATF. A feedback system was deployed in the upstream section of the ATF2 extraction line, using high-resolution bunchposition measurements from stripline beam-position monitors (BPMs) [9], to demonstrate [10] the resolution, correction-range and latency requirements for the ILC IP beam collision feedback system [11]. An extended feedback system based on this hardware was recently used to stabilize the beam trajectory before its entrance to the final-focus region, and yielded a significant reduction in the impact of 'wakefields' on the beam-size growth [12].…”

A sub-micron resolution, bunch-by-bunch beam trajectory feedback system and its application to reducing wakefield effects in single-pass beamlines

“…2016 measurements with the system demonstrated a position resolution of 157 ± 8 nm for a beam charge of 1.3 nC (0.82 × 10 10 electrons/bunch) [8]. The processed BPM signals are input to a custom-made digital feedback ('FONT5') board [5,7]. The FONT5 board design features a Field-Programmable Gate Array (FPGA) along with nine analogue-to-digital converters and a pair of digital-to-analogue converters.…”

“…The position of the bunch is derived from the ratio ∆/Σ. A beam position resolution of 291 ± 10 nm for this system in operation at ATF2 has been reported [11]. In 2016 the system was upgraded [12], resulting in an improved position resolution of 157 ± 8 nm (FIG.…”