• Dr.
    • Johan Messchendorp
    • GSI-FAIR - Germany
    • Nuclear Physics

Subatomic physics at extremes

Subatomic physicists try to unravel the building blocks of visible matter by colliding particles at extreme energies and intensities to investigate the underlying physics on impressively tiny scales, smaller than the size of a proton. The aim is to discover new forms of particles to challenge our standard model of particle physics and to shed further light on how subatomic matter is being formed from its elementary building blocks. Large particle-accelerator facilities at various places in the world are in construction or being planned to push the limits even further. At the same time, the instruments used to observe the radiation products during particle collisions are becoming immensely complex. The number and diversity of sensors of modern particle detectors are impressively large. Under very harsh conditions with unprecedented data rates, a complex computational network composed of autonomously operating processes is developed with the aim to reliably and in-situ extract valuable information from the raw data registered by the many sensors. In many cases, researchers are hunting for rare processes, i.e. searching for a tiny needle in a huge haystack. Machine learning methods have become a standard in the development of fast low-level pattern recognition, particle identification, clustering and reconstruction algorithms. These techniques will become even more important for the online operation of the experiment, leading to a paradigm shift in the data handling and experiment control. The third wave of artificial intelligence is emerging, also in the field of experimental subatomic physics!


Johan Messchendorp did his PhD research at KVI (Groningen), the former nuclear physics laboratory in the Netherlands, and obtained his degree in 1999 at the university of Groningen. After a period of 3-4 years as a postdoc at the university of Giessen, Germany, he became assistant professor at the RuG (KVI-CART) and got promoted in 2010 to an associated professor. During the time in Groningen, he was the principal investigator of the spin-physics program at KVI-CART, thereby constructing a complex detection system and performing a series of high-precision few-nucleon scattering experiments. Moreover, he joined two international large-scale projects in the field of hadron (QCD-driven) physics, namely PANDA (Germany) and BESIII (China), leading various computing and physics activities. As a pioneer of the center of data science and system complexity (DSSC) at the RuG, he represented the data science aspects in the context of particle physics. Since 2017, he is the scientific coordinator of the PANDA collaboration leading the development of its broad physics program and coordinating the various analysis activities. In 2022, he moved to GSI/FAIR in Darmstadt, Germany, as a group leader at the FFN department and in charge of the conceptual design of the FAIR computing infrastructure.