Péter Lévai, Director of the Institute for Particle and Nuclear Physics and Director General of Wigner Research Centre for Physics, outlines recent research activities in Csillebérc, Budapest, in the area of modern physics.
Hungarian traditions in physics
In books on the history of science, the interested reader will quickly find Hungarian-born scientists well-recognised in the fields of modern physics during the first half of the 20th century. Roland Eötvös, Eugene P Wigner, Edward Teller, Leo Szilard, Theodore von Karman, and John Neumann have created fundamental pillars of classical and quantum physics, nuclear physics, particle physics and computer science. In the last 70 years, many Hungarian physicists working in Hungary and all around the world were eager to demonstrate that they are worthy successors of these Titans of science, on both the theoretical and experimental sides.
In 2012, the Hungarian Academy of Sciences established the Wigner Research Centre for Physics (RCP), merging together the Institute for Particle and Nuclear Physics and the Institute for Solid State Physics and Optics (originally both institutes were established in 1975). The name of Eugene P Wigner connects the past and the present, generating an outstanding scientific mission for 300 scientists which attracts many young people to several fields of modern science cultivated at Wigner RCP. The main focus of the Research Centre is on fundamental research, but we always welcome opportunities for applications and innovations. Located within the Budapest suburb of Csillebérc, the Wigner RCP is ideally positioned to perform fundamental research and to establish high-tech laboratories. Here, both environmental conditions and human resources are available for cutting-edge research activities. Below, we explore how Hungarian scientists have used these opportunities during the last decade and what they are planning for the near future.
CERN at Wigner mission: Pillar of high energy nuclear and particle physics
Hungary joined CERN in 1992 and, over the last 30 years, around 100 Hungarian physicists have participated in international collaborations near the Super Proton Synchrotron (SPS), Large Electron-Positron (LEP) collider, and now at the Large Hadron Collider (LHC). In addition, we are also now looking forward to the Future Circular Collider (FCC).
We searched relentlessly for new symmetries of the fundamental interactions, the scalar Higgs, the quark-gluon plasma, exotic particles, and we are continuously trying to reach beyond the Standard Model. In the meantime, we have built detectors, special sensors, and electronics for data acquisition, and we have carefully analysed the huge amount of physical data collected. Aside from being a successful and reliable collaboration partner, we transferred a large part of the collected knowledge from CERN to Hungary. Several young colleagues remained in the field of high energy nuclear and particle physics, but many of them moved on to European and Hungarian companies in industry, offering their international experience and competence to both small- and large-scale enterprises.
New local opportunities for Hungarian scientists
Initially, most of the Hungarian scientists were positioned at the CERN site in Geneva, but the opening of new laboratories at Wigner RCP has enabled numerous R&D projects to be executed locally over the last ten years. The detectors at LHC are a good example. We participated in the construction of the ALICE and CMS detectors on-site in Geneva around 20 years ago, but we were able to carry out work during the LHC’s Long Shutdown 2 (LS2) on part of ALICE’s new Time Projection Chambers (TPC) in our Innovative Detector Laboratory locally, in Csillebérc. Now, our clean laboratories (ISO6) are ready to start quality-assurance-related works for the CMS PIXEL upgrade and are already in consideration for the local construction of certain elements of the ALICE3 upgrade. In parallel, Remote Operation Stations have been established for CMS and ALICE to perform high-quality data collection 1,300km from Geneva. These stations were extremely effective during the COVID-19 pandemic, as they enabled most service work to be performed from Budapest without a need to travel. This activity will be broadened in the future, decreasing cost, and assuring sustainable participation in international collaborations.
In the Innovative Detector Laboratory, large-size multilayer gaseous detectors were developed to precisely determine the path and direction of charged particles. During the last five years, these detectors improved in size, energy consumption, robustness, mobility, and autonomy. The latest versions are excellent instruments for cosmic ray measurements in harsh environments, capable of scanning extremely large-size objects by cosmic muons. This method is known as muography. Recently, the Sakurajima Muography Observatory has been installed and operated in North Japan, and, in collaboration with the University of Tokyo, Hungarian physicists are monitoring the level of hot lava inside this active volcano, demonstrating the successful applicability of this method. A new collaboration is also underway at the Etna volcano in Sicily.
High-performance detectors demand high-quality data handling. In the DAQ Laboratory, electronic devices are developed for high-speed data acquisition by engineers with vast experience working on FPGA and other special electronic units. This group is responsible for the operation of the DAQ system at LHC, the ALICE detector and, recently, group members have performed R&D activity for improving other detectors at CERN, GSI/Fair, and JINR/NICA. In recent years, the experience with FPGAs has been beneficial in the process of installing cutting-edge data acquisition instruments in different projects (e.g., in geophysical experiments) and exploring their applicability in massively parallel computers and in quantum computer emulators, which is our parallel mission.
We have a long history of developing detectors and DAQ units, but the recent upgrade activity at LHC and construction plans for the Future Circular Collider (FCC) at CERN led us to establish a new research group for R&D on superconducting accelerator magnets. Currently, the group is focusing on special kick-out magnets for beam control. Extended simulation work led to new solutions, and the production of these instruments is now taking place in a newly established laboratory.
VLAB for international collaborations
These activities and units were integrated into the Vesztergombi High Energy Laboratory (VLAB) in 2017, which is operated as an Open Laboratory offering services for other players of high energy physics. György Vesztergombi (1943-2016), a worthy successor of Eugene P Wigner, is well-recognised for his career as a high energy physicist, and his coordination of Hungarian participation in CERN experiments for 25 years. His experience demonstrates the importance of a mission-guided, well-prepared scientist, and shows how opening opportunities can be converted into successful scientific projects. His students are some of the most trustworthy staff members of the Wigner RCP today.
VLAB includes the Janossy Underground Research Laboratory (JURLab) at Csillebérc, located 30m underground, where cosmic ray experiments were performed from 1950-1960. After this time, single-photon interference was investigated, testing basic statements of quantum mechanics. The leader of this research was Lajos Jánossy (1912-1978), Director of the first Central Research Institute for Physics in Csillebérc from 1956-1970. The JURLab has recently been renovated and modernised, creating a perfect environment for experiments that demand low noise, consistent temperature and humidity. In parallel, the Mátra Gravitational and Geophysical Laboratory (MGGL) was established in 2015, 80m underground in the Mátra Mountain Range, 80km from Budapest in a closed ore mine. These underground units of VLAB offer excellent opportunities for the development of detectors for muography, alongside the ability to host other scientific experiments, especially in gravity. Today, long-term experiments are running remotely in the JURLab, with modernised Eötvös balance studying the nature of Newtonian Noise and earthquakes in geophysics, as well as the decay of short lifetime rare isotopes.
The Vesztergombi High Energy Laboratory integrates all experiment-related R&D activities in the Institute of Particle and Nuclear Physics. In 2021, the VLAB received the qualification to be listed amongst the Top 50 research infrastructures of Hungary.
In 2021, the European Committee of Future Accelerators (ECFA) released the Roadmap on Detector R&D and the Roadmap on Accelerator R&D, unifying the efforts of European research laboratories and institutes for the creation of modern research instruments. In April 2021, the initiative of Joint ECFA-NuPECC-APPEC Activities (JENAA) was launched as a special, large-scale collaboration among institutes working on high energy physics, nuclear physics, and astroparticle physics to explore and mitigate opportunities of mutual R&D activity, increasing the efficacy and sustainability for the benefit of all disciplines. The aim of VLAB is to offer a solid basis for a fruitful participation of Wigner RCP in the above initiatives of the European R&D efforts.
Development of plasma-wake accelerators
Traditional accelerators consist of electromagnetic elements with macroscopic size. In recent years, the exploration of laser-plasma interaction and the study of plasma wakefield has led to a new direction promising compact accelerators. The core idea is connected to the creation of strong wakefields in plasma by laser or particle beams. Fortunately, in one of the local laboratories, atom-laser interaction was studied for decades in low temperature rubidium vapour and world-class knowledge on resonant interaction was collected, both on the experimental and theoretical (simulation) sides.
In 2015, the installation of a Coherent Hydra Ti:Sa laser system with pulse energy 30mJ and pulse duration 30fs turned the group activity into this new direction. The group’s unique knowledge on resonant interaction with rubidium and the local laboratory setup gained the team access to join the CERN AWAKE collaboration and to participate in the experimental study of plasma wakefield phenomena as a new, innovative method of particle acceleration. The progress in the field generated an enhanced interest in Europe and the EUPRAXIA collaboration was established to create small-size electron accelerators with low-energy consumption and easy operation, allowing for a variety of biological, medical and industrial applications. Hungary joined the EUPRAXIA initiative at the national level. In 2021, EUPRAXIA was accepted into the ESFRI Roadmap 2021 and Wigner RCP, with this laboratory, became the active participant of this European endeavour.
CERN at Wigner mission: Pillar of informatics
High energy particle and nuclear physics would not prosper without modern information technology and the application of cutting-edge developments of the IT-sector. We are recognised for using the most modern computers in our institute. This story dates back to the 1960s, when the first URAL computer was installed to support research activity at Csillebérc. From 1985, personal computers and DEC workstations helped to accomplish world-class theoretical projects and data analysis in experiments. In 1995, we invested in a 64-bit Silicon Graphics cluster, with graphical software capable of generating very informative graphical output on large-size monitors, which were included in the daily research activity (uttering a more effective era of computing intense sciences). In 2000, an SGI ICE supercomputer was installed to support the preparation work of the CERN LHC, performing superb simulations and theoretical investigations in high energy physics – parallel ways executing early DNS-sequencing projects in collaboration with experts of bioinformatics. In 2002, following the demand of the CERN LHC ALICE and CMS collaborations, the first CERN Tier-2 grid unit was put into operation with 200 vCPU. Over the last 20 years, this Tier-2 was expanded to a 4000 vCPU unit and is continuously working as one of the top three Tier-2 sites of CMS, pertaining reliability and performance.
The Wigner Data Centre
In 2012, CERN set up a new initiative, turning the on-site Tier-0 capacity into a distributed Tier-0 network. The main aim was to extend the capacity of the on-site 3 MW IT centre. Wigner RCP participated in the tender and won the procurement process. We constructed the Wigner Data Centre with 4 MW IT-capacity and 2×100 Gbit/sec connection to CERN. In January of 2013, the Data Centre began hosting the CERN computers and became the extension of CERN Tier-0 in the seven years that followed. We were able to serve CERN with the highest IT standards, generally without interruption. This was a fantastic collaboration, and many Hungarian experts attained additional knowledge on distributed computer technologies, and high-efficiency grid-computing. In 2020, CERN changed its priorities and started to construct a huge on-site IT centre, concluding our contract. However, the positive outcome was that we regained a world-class Data Centre to support local IT requests.
WSCLab for supporting research
Today, one hall of the Wigner Data Centre, with 1MW capacity, is already serving scientific missions. The Wigner Scientific Computing Laboratory (WSCLab) integrates several dedicated IT resources supporting research activities. Near the CERN ALICE and CMS Tier-2 sites, a special test-cluster, the ALICE Analysing Facility, is located with 3700 vCPU and offers the opportunity to develop cluster software for multicore environments. A dedicated Tier-2 cluster for VIRGO Collaboration on gravitational wave detection is operating with 1000 vCPU, and a smaller cluster will soon serve the EUPRAXIA initiative on laser-plasma accelerators. The WSCLab is open for scientific missions, especially if they are listed on the ESFRI Roadmap. In 2021, the WSCLab also received the qualification to be listed amongst the Top 50 research infrastructures of Hungary.
GPUs, FPGAs, and Quantum Computing
The GPU-focused studies have a decade-long history at Wigner RCP, motivated by the ever-growing demand for computing power from high energy physics and theoretical physics. Today, WSCLab offers cutting-edge hardware elements for experienced users to execute their scientific studies promptly (8×Ampere A100 SXM4 and 14×Tesla T4). Beginners can join the annual meetings and training courses, deepening their knowledge in multiplatform, fast calculations. The latest WSCLab project is connected to quantum programming, and a Maxeler FPGA Unit computer will soon serve the eager community as a quantum computer simulator. This development is connected to CERN’s Quantum Technology Initiative (QTI), which has recently launched its roadmap, integrating international efforts. New proposals are under construction to the HORIZON EUROPE DIGITAL-QCI Calls on quantum information and the deployment of an operating national network.
At the beginning of 2020, the new Department of Computational Sciences was established at the Institute for Particle and Nuclear Physics to accumulate local and foreseen scientific expertise. The research groups of this department are very active in the fields of Artificial Intelligence (AI) and brain research, Machine Learning (ML), deep learning, big data analysis, machine-human interfaces, quantum programming, and quantum information. Our scientific credo is based on the close collaboration between cutting-edge science and information technology.
GW at Wigner: Gravitational waves
Traditionally, gravitation experiments are not part of HEP activity, however the two disciplines have recently started to merge. The Grand Unification Theories (GUT) of particle physics and the study of extra dimensions consider electrodynamical, weak and strong interactions together with gravitation in many aspects, however the experimental sides have been separated so far. The idea of a giant European underground facility for detecting gravitational waves at never-before-seen precision drove these disciplines closer. The Feasibility Studies of the Einstein Telescope (ET – 30km triangle tunnel) and the Future Circular Collider (FCC – 100km circular tunnel) highlighted so many similarities that recently CERN has accepted an agreement on mutual studies and R&D programmes with the organisers of the ET to collaboratively solve these overlapping technological problems. Thus, high energy physics and gravitation will be strongly connected not only theoretically, but instrumentally, as well. At Wigner RCP, we are ready to join these mutual efforts to develop our expertise.
Gravity roots deep in the Hungarian spirit. At the end of the 19th century, Roland Eötvös constructed and fine-tuned the Eötvös balance to measure the weak equivalence principle, the gravitational constant and, as a side-effect, to explore underground ore and oil reserves. Modern theoretical studies started 40 years ago at Wigner RCP, and 15 years ago we joined the VIRGO Collaboration to measure gravitational waves. Our colleagues were awarded by the Breakthrough Prize in Fundamental Physics in 2016 as members of the LIGO/VIRGO Collaboration for the direct detection of gravitational waves. Today, we are actively participating in the planning of the Einstein Telescope. Data analysis, computer grid operation (see Virgo/ET-Grid), infrasound and dedicated seismic investigations have been performed at Csillebérc and the aforementioned MGGL underground laboratory in the Mátra mountain. We would like to extend our activity, and currently collaborations are taking place on ET-related engineering and laser technologies. Fortunately, young students are ready to join to these studies and R&D activities, so we foresee interesting and important diploma and PhD theses in these fields.
A bright future for scientific research
This short overview demonstrates the recent activity of Wigner RCP in different fields of high energy physics and related scientific disciplines. However, many activities presently cultivated or prepared for the future of science were not mentioned, including theoretical studies. We pertain that scientific research has a bright future and we are eager to contribute both experiments and R&D efforts, as well as theoretical studies.
Please note, this article will also appear in the ninth edition of our quarterly publication.