Welcome to the Institute for Nuclear Physics

The Mainzer Microtron MAMI, an electron accelerator for energies of up to 1,6 GeV, is the core of experimental investigations. Additionally, scientists at the Institute of Nuclear Physics are working on the theoretical description and interpretation of the experimental results and of external experiments in, for example, Beijing (IHEP), Darmstadt (GSI) and Geneva (CERN).

Current news – FB 08 – Kernphysik (eng)

New physics in parity violation: From the Thomson limit to the energy frontier / Funding worth EUR 3.2 million

11 April 2024

Professor Maarten Boonekamp, Professor Frank Maas, Professor Jens Erler (photo/©: private / Sabrina Hopp)

The consortium of Professor Maarten Boonekamp from Université Paris-Saclay as spokesperson and Professor Jens Erler and Professor Frank Maas of Johannes Gutenberg University Mainz has been awarded an ERC Advanced Grant for their project Zeptometry. This project aims to combine new precision measurements at the highest LHC energies at the European Organization for Nuclear Research CERN with challenging new precision measurements at very low energies with the upcoming MESA accelerator in Mainz in connection with the theory interpretation of the experimental results. The funding will be dedicated to the study of interactions between the Z boson and the fermions, i.e., the quarks and leptons constituting ordinary matter, to which end the upcoming experiment P2 at the Mainz electron accelerator MESA will be crucial.

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Quelle: 2003-2024 CERN / Herwig Schopper, CC BY-SA 4.0 Deed

The founding director of our Institute turns 100 today

28 Feb 2024

Herwig Schopper, a pioneer in experimental particle physics in Germany and Europe and the founding director of the Institute of Nuclear Physics at the Johannes Gutenberg University Mainz celebrates his 100th birthday today.

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photo: W. Gradl

The "International Conference on Meson-Nucleon Physics and the Structure of the Nucleon (MENU 2023)" took place in the historic building of the Erbacher Hof in the old town of Mainz from October 16 to 20, 2023. More than 140 participants from 15 countries discussed their research results on topics in the field of hadron physics and related areas in 26 plenary and 77 parallel lectures sessions. Future developments in this field of research, such as the Electron-Ion-Collider in the USA and the Mainz Energy Recovering Accelerator MESA in Mainz, as well as new forward-looking developments in theory, also played a major role.

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In order to operate the new electron accelerator MESA, an extensive technical infrastructure is required in addition to the actual accelerator components: for example, a cryogenic system based on liquid helium for cooling the superconducting accelerator units. This cryosystem was designed by the scientists and technicians of the Institute of Nuclear Physics to be recoverable, i.e. the part of the liquid helium that evaporates during the cooling process is subsequently fed back into a liquefaction plant and can thus be reused. A central component for this is the so-called sub-atmospheric compressor, which has now been successfully installed by the staff of our technical operating unit "Vacuum" together with the manufacturing company. This large compressor with a footprint of about three by six meters is used to first compress the helium vaporized in the system from a pressure of around 16 mbar back to atmospheric pressure (~1 bar) before it is then furher increased to the liquefier's working pressure of around 10 bar via another group of compressors.


Powerful magnets for MAGIX

Core components for the upcoming MESA experiment MAGIX have arrived in Mainz

photo: Kathrin Schlimme

One of the key projects of the Mainz Cluster of Excellence PRISMA+ is the construction of the new energy-recovering particle accelerator MESA, which will enable experiments with unprecedented precision in the future. One of these experiments is called MAGIX. It is a sophisticated spectrometer setup with which scientists hope to answer some of the most fundamental questions in modern physics: How big is the proton? Can we find evidence for dark photons? Can we understand more precisely the fusion of carbon and helium into oxygen inside stars? Now, with two magnet systems weighing 18 tons each, very crucial components for MAGIX have arrived in Mainz.

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The "25th European Conference on Few-Body Problems in Physics" took place this year on the campus of JGU Mainz. In 13 sessions over 5 days more than 150 scientists from all over the world discussed current issues in the fields of hadrons, (hyper-)nuclear physics, cold atoms and molecular physics. Ukrainian researchers were connected online, as they were unable to attend on site due to the war in Ukraine.

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After years of development work, the new Pixel Vertex Detector (PXD2) was successfully installed in the international Belle-II experiment at the SuperKEKB electron-positron accelerator in Japan. Concettina Sfienti's group at the Institute of Nuclear Physics was also involved in the design and construction. Under Mainz leadership, real-time monitoring of data quality was implemented and key sections of the software controlling the PXD2 were programmed. In addition, sensor modules were tested at MAMI for their radiation hardness.

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From 26.06.23 to 30.06.23, this year's workshop of the "Proton Radius European Network" (PREN 2023) and the "Muonic Atom Spectroscopy Theory Initiative" (µASTI) took place in the premises of HIM at JGU Mainz. Over the five days, more than 50 scientists from more than a dozen countries discussed their research on the structure of nucleons and nuclei, as well as the search for New Physics, by confronting precise theory predictions with electron scattering experiments and spectroscopy of in part exotic atoms and molecules. "Overall, we had a very diverse program with many exciting discussions that motivate and inspire us to work even more closely on common issues in the future. We are already looking forward to the next event," summed up local organizers Franziska Hagelstein (Institute of Nuclear Physics) and Randolf Pohl (Institute of Physics).

We congratulate Dr. Micro Christmann on the completed dissertation entitled

"Design Studies for the Beam Dump Experiment DarkMESA"

In his PhD thesis Mirco Christmann from the group of Prof. Achim Denig has performed a full scale design study for one of the three experiments under construction for MESA - the DarkMESA experiment. This uses the P2 beam trap as a target for the possible production of light dark matter particles. In the DarkMESA detector, which is well shielded more than 20 meters behind the beam catcher, there is the possibility to detect the dark matter particles by interaction with the electrons in the detector material.

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We congratulate Dr. Robert Heine, who successfully completed his habilitation with his inaugural lecture on the topic

The Milliamp Booster MAMBO or "How to build an injector linac for MESA ?"

More about the new electron accelerator MESA and the planned experiments can be found here.