image: JGU President Professor Dr. Georg Krausch welcomes the participants of the annual meeting of the ATLAS Collaborative Research Center
Credit: Bernd Eßling
The connections between particles and their mass, the composition of the universe out of matter and antimatter and the search for previously unknown particles such as the so-called “dark matter” are the focus of researchers at the research center CERN in Geneva, which is celebrating its 70th birthday this year with events all around the world. In four large-scale experiments, scientists at the Large Hadron Collider (LHC) are getting to the bottom of the secrets of the universe. This particle accelerator offers researchers the unique opportunity to recreate the energetic conditions shortly after the Big Bang and thus investigate fundamental questions of elementary particle physics and cosmology: Two high-energy proton beams of 3.5 tera-electronvolts each have been colliding at the LHC since March 2010, resulting in a center-of-mass energy of 7 tera-electronvolts. This was increased to 13.6 tera-electronvolts in 2022 after a multi-year upgrade phase. The interactions that take place in these collisions are measured using two multipurpose detectors. The larger of these is called ATLAS, weighs 7,000 tons and is an impressive 46 meters long and 25 meters in diameter. It was used to discover the Higgs boson in 2012, the properties of which have since been researched in more detail by several working groups. The international ATLAS collaboration has a total of around 6,000 members from 41 countries.
Mainz contribution to the ATLAS experiment
In Germany, 17 universities and research institutions are involved in the ATLAS experiment, including Johannes Gutenberg University Mainz (JGU), represented by the Experimental Particle and Astroparticle Physics (ETAP) group at the Institute of Physics (working groups of Professor Volker Büscher, Professor Lucia Masetti, and Professor Stefan Tapprogge), which is an important part of the Cluster of Excellence PRISMA+. JGU is responsible for instance for the construction and operation of high-speed electronics for the so-called trigger of the ATLAS detector, which is used to decide fully automatically 40 million times per second which data from the detector will be stored for later analysis. The research is funded by the German Federal Ministry of Education and Research (BMBF) via a collaborative research center (Forschungsschwerpunkt, FSP) within the framework program “Exploration of the Universe and Matter” (ErUM).
Annual meeting back at JGU after 14 years
The German research groups involved in the ATLAS experiment work closely together on the operation, data analysis and upgrade of the detector and make key contributions to the development, construction and upgrade of all ATLAS detector systems. These include, for example, the pixel detector, the liquid argon calorimeters and the muon detectors, as well as various trigger systems that can be used to select specific particle collisions at the LHC. Once a year, the members of the ATLAS-FSP meet to discuss results of the ATLAS experiment, analyze the recorded data and coordinate future work. This year, the meeting will take place on the JGU campus for the first time since 2010 and will mainly focus on data analysis from the third run of the LHC (“Run 3”) and the upgrade of the ATLAS detector planned for 2030: The LHC will be upgraded to the so-called “High-Luminosity LHC” (HL-LHC), which will allow the beam intensity to be increased almost tenfold, but will also pose new challenges for the ATLAS detector. “Johannes Gutenberg University Mainz is grateful to host this workshop to promote scientific exchange between the German ATLAS groups,” emphasized JGU President Professor Georg Krausch. “As president, I am pleased that JGU will continue to make a strong contribution to the High-Lumi LHC in the future and, in doing so, promote our university’s international visibility.” “With the new data from Run 3 and the HL-LHC in particular, we have the unique opportunity to precisely study the newly discovered and still very mysterious Higgs particle and thus make completely new discoveries about the physics of our universe,” explains Professor Volker Büscher. The annual meeting of the ATLAS-FSP ends tomorrow, Friday, September 13.