Research into the basic building blocks of matter and their fundamental interactions is part of global research efforts. Numerous large-scale international experiments, which have either already begun collecting data or will start operating over the next decade, are dedicated to this exciting challenge. PRISMA++ scientists are involved in many of them. They aim to make important contributions to answering a number of fundamental open questions in this field of research:
- Are there new particles or new forces beyond the Standard Model of Particle Physics?
- What is the origin of mass?
- Why does the universe have more matter than antimatter?
- What is dark matter made of?
To find answers to these questions, research at PRISMA++ encompasses five fundamental, interconnected fields of research. The common goal is to investigate fundamental forces and symmetries, their connections to the existence of new particles, the internal structure of ordinary (visible) matter, and the nature of dark matter and its interactions with the visible sector.
At JGU, the exploration of the fundamental building blocks and interactions of nature is characterized by a wide range of complementary approaches and methods used to answer these questions, such as:
- Experiments at particle accelerators
- Neutrino telescopes and experiments to search for dark matter
- Precision spectroscopy and magnetometry, as well as experiments with atom and ion traps
- Reactor-based experiments with cold and ultracold neutrons
- Theoretical calculations and modeling
PRISMA++ particularly benefits from the expertise available in Mainz in the areas of numerical methods and high-performance computing, as well as the extensive experience in the design and operation of large experimental and accelerator facilities.
The PRISMA++ research program targets some of the most interesting aspects of modern Particle Physics, astroparticle and hadron physics. It consists of five fields of research:
RA-A is dedicated to the unique physics opportunities offered by the MESA accelerator and its MAGIX and P2 experiments. With the P2 experiment, PRISMA++ scientists will set a new precision standard for the measurement of the electroweak mixing angle at low energy and initiate a new generation of experiments for parity-violating procedures required for the clause of the neutron skin in heavy nuclei. The MAGIX spectrometer with its novel gas target will make it possible to measure the scattering of electrons with low momentum transfer, improving our understanding of nucleon form factors and charge radii.
The main goal of RA-B is to prove the existence of particles beyond the Standard Model by studying quantum loop effects. Its main activities include resolving the Cabibbo angle anomaly and making precise measurements of the neutron’s lifetime, the weak mixing angle, and nuclear charge radii. The program also involves a comprehensive investigation of the muon’s anomalous magnetic moment. This research relies significantly on innovative investigative methods developed by PRISMA++ scientists, such as laser spectroscopy of muonic atoms and neutron magnetic traps, as well as contributions to major international experiments, including ATLAS and NA62 at CERN and Ï„SPECT at PSI. High-precision calculations complement these experimental efforts, maximizing sensitivity to new physics effects via loop corrections.
RA-C explores physics beyond the Standard Model by investigating the properties of neutrinos and the origin of their masses. Key contributions to the international experiments JUNO, IceCube, Project 8 and DUNE address the problem of neutrino mass hierarchy and the absolute scale of neutrino masses. In particular, a combined analysis of the neutrino oscillation data with a focus on the IceCube Upgrade and JUNO experiments is crucial for the resolving of the mass ordering. In addition, the combination of expertise in advanced scintillator technologies at the PRISMA Detector Lab will enable the demonstration of new technologies for future experiments.
RA-D is pursuing a broad range of innovative approaches in the search for dark matter. These include the search for new particles and forces as well as research into new types of probes for the early universe. The GNOME and CASPEr experiments in Mainz use highly innovative methods to search for axions and axion-like particles. The underground DARWIN/XLZ experiment with its improved sensitivity is used for the direct detection of dark matter in the GeV-TeV range. In addition, the ATLAS experiment uses data from the high luminosity phase of the LHC to also search for weakly interacting dark matter in the TeV range. The sensitivity will be further improved by the new SHiP experiment at CERN.
The activities of RA-E explore fundamental physics on all scales. Theorists from PRISMA++ work at the forefront of innovative methods in quantum field theory, such as perturbative high-order calculations, applications of effective field theories, and new procedures in Lattice Gauge Theory. Other important fields of research include physics beyond the Standard Model, astroparticle physics, mathematical physics, and string theory. Additionally, numerical techniques developed using machine-learning tools improve the close interplay between theory and experiment, greatly enhancing the prospects for discovering new physics.
For many years, scientists in Mainz have benefited from the excellent and unique local research infrastructure on the JGU campus. This currently includes the MAMI accelerator, which is built and operated by the Institute for Nuclear Physics, and the research reactor TRIGA Mainz at the Institute for Nuclear Chemistry, which serves as a high-quality source of ultracold neutrons.
These institutions are complemented at PRISMA++ by:
With MESA, we are exploring the possibilities that the recently established Energy-Recovery-Linac (ERL) accelerator technology offers for physical experiments. This new technology enables very high luminosities of the electron beam, which is aimed at “internal” targets at low energies. MESA is the first accelerator to use multi-turn energy recovery in a superconducting environment. The machine will thus serve as a test environment for other large-scale facilities worldwide, such as the LHeC [1].
The MESA accelerator and the associated experiments will extend over several basement levels and also include a new experimental hall, which will be built as part of the CFP research building. Im April 2024 wurde erstmals ein Elektronenstrahl mit MESA erzeugt.
MESA is not only a groundbreaking project for ERL applications, the accelerator also paves the way for important experiments in Particle Physics. Several key experiments are currently under development. Two of these, P2 and MAGIX, are already in an advanced stage of development.
The P2 experimentconducted in extracted beam mode will outperform existing measurements of the electroweak mixing angle at low energies by more than an order of magnitude. In addition, it enables a new generation of parity violation experiments needed for the clause of the neutron skin of heavy nuclei. With MAGIX offers the world’s first opportunity to operate a high-intensity ERL beam in combination with an internal gas target. The MAGIX multipurpose spectrometer also allows the precise measurement of proton form factors and the search for dark photons. The direct search for dark matter particles is carried out in DarkMESA and will benefit from the exceptionally high number of accelerated electrons in the MESA accelerator.
Collaborations:
In June 2015, the Joint Science Conference (GWK) approved the grant for the new research building “Center for Fundamental Physics (CFP)”. The new research building provides the necessary infrastructure for the expanded PRISMA++ research program. It consists of two separate parts: Once completed, the CFP will offer office space and laboratory space on the one hand and an underground experimental hall on the other.
The underground experimental hall provides the necessary space and infrastructure for the MESA accelerator and its experimental facilities. The hall thus covers the additional space requirements resulting from the significantly expanded research program at MESA.
Some of the newly established work groups will be housed in the above-ground part of the new complex. In addition, special laboratories for detector development will be institutionalized there, including a clean room and an assembly hall where large detector parts can be assembled. A conference room and offices for visiting scholars and the PRISMA++ administration will also be housed there.
In the spring of 2018, construction work began on the underground part of the CFP research building. In order to be able to build the experimental hall of the new MESA particle accelerator at a depth of ten meters, old ancillary and workshop buildings on the site of the Institute for Nuclear Physics first had to give way. The new workshops have already been occupied.
The PRISMA Detector Laboratory promotes collaboration as well as the exchange of experience and technology within PRISMA++. It provides laboratories and workplaces to offer scientists with different hardware expertise a common research environment and infrastructure.
As part of this collaboration, the detector laboratory offers access to its own special laboratories, high-quality equipment and design software. The electron and photon beams at MAMI and the irradiation facility at the TRIGA reactor are also available for the examination and characterization of detectors and electronics.
The MITP is one of the main initiatives of the cluster and is intended to take on the role of an international theory center in the long term. It was founded in November 2012 as part of the cluster of excellence PRISMA; the founding director is Professor Matthias Neubert (JGU Mainz). The MITP unites the theoretical activities in all fields of research of PRISMA++ under one roof and promotes collaboration between the various fields.
To this end, the institute organizes scientific programs, workshops and conferences with the involvement of external researchers. In this way, it offers scientists from different research areas of theoretical physics the opportunity for interdisciplinary exchange.
Approximately 100 doctoral candidates and 90 postdoctoral researchers are currently conducting research in the various areas of the Mainz cluster of excellence PRISMA++. With their commitment, their ideas and their thirst for knowledge, they make an indispensable contribution to the implementation of the PRISMA++ research program. In no particular order, in the section “What are you currently researching?” we present young researchers and their research projects.
The PRISMA++ cluster of excellence thrives on the excellence and diversity of its members. They form an interdisciplinary network with innovative research approaches and international experience. In the “New at PRISMA” section, we introduce you to the outstanding scientists we have been able to recruit for our cluster. We are delighted to welcome these new co-workers to our scientific community!
