Figure 1. From left to right: Shervin Shirmohammadi, President of the IEEE Instrumentation and Measurement Society;Jill Gostin, President-Elect of IEEE; Nikolai Beev, author, CERN; Roberto Ferrero, Editor-in-Chief of IEEE Transactions on Instrumentation and Measurement. Photo courtesy of IEEE.

By Michele Martino and Nikolai Beev (CERN)

The article Design and Metrological Characterization of a Digitizer for the Highest Precision Magnet Powering in the High Luminosity Large Hadron Collider, published in the IEEE Transactions on Instrumentation and Measurement (TIM), has received the 2025 Andy Chi award from the IEEE Instrumentation and Measurement Society. The recognition of this contribution to TIM highlights a specific intersection between accelerator engineering and high-precision measurement science.

The digitizer presented in the awarded paper directly contributes to the measurement subsystem of the warm powering system of the HiLumi LHC, enabling the level of accuracy required for magnet powering in the upgrade to the accelerator.

The award was officially presented at the I2MTC conference in Nancy, France on 27th May 2026. The paper is co‑authored by Nikolai Beev, Miguel Cerqueira Bastos, Michele Martino, Daniel Valuch of CERN, as well as Luis Palafox and Ralf Behr of PTB-Braunschweig. It results from a collaboration between the two institutes, and describes a new metrology-grade digitizer developed at CERN and tested and characterised extensively at the highest level using a Programmable Josephson Voltage Standard at PTB-Braunschweig.

Figure 2. Series units of HPM7177 (left), and characterization setup for the HPM7177 with the Programmable Josephson Voltage Standard at PTB-Braunschweig (right). Nikolai Beev / CERN

A highly selective award in a large-scale journal

The Andy Chi Award recognises the best paper published annually in TIM, which is a Q1 journal in both Electrical and Electronic Engineering and Instruments and Instrumentation. In recent years, the journal has grown significantly, publishing in the order of 2400 papers per year, selected among approximately 14,000–15,000 submissions annually. This corresponds to an acceptance rate of roughly 25% and places the award among the most selective recognitions in the field. In this context, the award-winning paper represents around 1 out of 2400 published papers, and ultimately 1 out of more than 10,000 submitted manuscripts.

Instrumentation at CERN and the TIM scope

CERN has strong and long-standing expertise in instrumentation, particularly in areas related to particle accelerators and detectors. However, the IEEE Transactions on Instrumentation and Measurement represents a specific niche within the broader instrumentation landscape, with a strong focus on measurement science and metrology, precision electronic instrumentation, and calibration and uncertainty evaluation.

CERN instrumentation activity is more commonly disseminated in journals dedicated to accelerator and detector technologies. As a result, the number of CERN publications in TIM remains relatively limited – only a small fraction of the journal’s annual output.

Seen in this context, the recognition of a CERN-led contribution in TIM highlights a specific intersection between accelerator engineering and high-precision measurement science, rather than a core publication channel for CERN activities.

A specialised contribution within accelerator systems

The awarded paper addresses the design and metrological characterisation of a high-precision digitizer (ADC-based measurement system), allowing for reaching the unprecedneted precisions for magnet powering in the HiLumi era. Within the overall domain of particle accelerators, such systems constitute a highly specialised subset, focusing on precision current measurement, stability, and noise performance at very low frequencies, and aspects of traceability and calibration.

Quantum voltage standards based on the Josephson effect are the most accurate voltage sources in existence, allowing for ultimate precision testing of electrical metrology equipment. PTB-Braunschweig is one of the pioneers and global leaders in the development and application of Josephson voltage standards.

Relevance for the Hilumi LHC and the project’s Warm Powering work package

This work fits directly within the scope of the HiLumi LHC Work Package (WP) 6B, responsible for warm powering, and therefore the development and deployment of power converters and associated systems for the upgraded machine.

WP6B aims to deliver high-performance power converters for new circuits in the interaction regions – systems achieving unprecedented precision and stability and high availability through state-of-the-art measurement and control subsystems.

Within this framework, measurement electronics – including precision digitizers – play a crucial role, as power converters are fundamentally composed of three subsystems: power, measurement, and control.

The digitizer presented in the awarded paper directly contributes to the measurement subsystem, enabling the level of accuracy required for HiLumi LHC magnet powering and thus supporting the overall machine performance targets.

Figure 3. The series of HPM7177 to be used in the HiLumi LHC (left), and a 2 kA power converter cabinet installed in IT-String, which uses the HPM7177 digitizers (right). Nikolai Beev / CERN

Open Hardware contribution

An additional noteworthy aspect of the work is that the presented digitizer has been released as Open Hardware. This approach facilitates dissemination and reuse, promotes transparency in metrological performance, and aligns with CERN’s broader commitment and strategic objectives to foster open science and technology transfer in support of the European technological landscape.

Perspective

The award recognises a contribution that lies at the intersection of accelerator engineering and high-precision measurement science. While this is not the primary focus of CERN’s publication activity, it is a domain where the requirements of the HiLumi LHC push instrumentation towards state‑of‑the‑art performance.

In this sense, the distinction reflects not only the quality of the work, but also the ability to address very specific and demanding technical challenges arising from the HiLumi LHC project.

Link to the manuscript in IEEE Xplore

Link to the Andy Chi award page at the IEEE Instrumentation and Measurement Society website