It combines research, research training and education of young researchers in three fields:
- Elementary Particle Physics (Theory and Experiment)
- Astroparticle Physics (Theory and Experiment)
- Advanced Technologies
The research topics in these three fields are given below. In each of the topics various PhD theses are possible.
The Pierre Auger Observatory covers an area of 3000 square kilometres in the Argentine Pampa with more than 1600 autonomous tanks: In highly pure water, energetic particles produce light flashes. In addition, four stations with 27 telescopes at the edge of the detector field observe the light tracks of cosmic particle showers. Underground muon detectors and an array of radio antenna stations complete the experimental set-up.
At lower energies experimental efforts in measuring cosmic rays were performed by the experiment KASCADE-Grande on KIT’s northern campus. The data are still being analysed and prepared for public use via the web interface KCDC. Other activities in this research field concern cosmic ray measurements from space (JEM-EUSO) and in the Siberian taiga (TUNKA-REX) as well as the air shower simulation package CORSIKA.
High-energy Neutrino Astronomy
IceCube is the neutrino observatory located at the South Pole consisting of optical modules within a cubic kilometer of Antarctic ice. Neutrinos, as almost elusive particles, are great cosmic messengers possibly pointing to the extreme astrophysical sources and giving insight to processes involved in creating highest energy particles. The surface part of IceCube, IceTop, including 162 ice Cherenkov tanks, enables the study of cosmic-ray air-showers and acts as a veto for astrophysical events. Our group at KIT is mainly working in the frame of the next generation of the IceCube experiment, IceCube-Gen2.
We search for Dark Matter particles by looking for collisions of WIMPs (weakly interacting massive particles) in germanium crystals. In the EDELWEISS experiment, up to 40 Ge detectors of 800 g each are cooled down to extremely low temperatures (20 milli-Kelvin). If a WIMP collides with a germanium nucleus, energy is deposited which leads to a temperature rise of the crystal of a few micro-Kelvin in coincidence with a charge signal. Requiring a characteristic ratio of both signals, background from radioactivity can be suppressed by more than 5 orders of magnitude.
EDELWEISS is a European project operated in the LSM underground lab. With its cutting-edge detector technology, it is one of the leading experiments in the international quest searching for Dark Matter particles. With EURECA, this technology will be expanded to a target mass in the ton range in a world-wide cooperation with the US-Canadian SuperCDMS collaboration.
Indirect Dark Matter Searches
Dark Matter makes up more than 80% of all matter in the universe. Assuming the Dark Matter particles to be thermal relics from the Big Bang, we only know that they must be WIMPs (Weakly Interacting Massive Particles). Such particles only exist in extensions of the Standard Model of Particle Physics, like Supersymmetry. They are predicted to annihilate into equal amounts of matter and antimatter. Such annihilations are similar to electron-positron annihilation, as studied in detail at accelerators, so the signatures are known, if WIMP annihilation really exists. To search for antimatter production from WIMP annihilation, one needs to have a magnetic spectrometer with redundant particle identification in space, since antimatter particles would annihilate in the earth atmosphere before reaching a detector on earth.
Quantum Field Theory
The fundamental building-blocks of matter, elementary particles, are described by the so-called standard model which provides information about their properties and the forces acting between them.
The research groups at KIT which work in theoretical particle physics perform complex perturbative calculations and non-perturbative considerations within the standard model or of hypothetical theories of New Physics in order to test the quantum nature of the theory and to extract fundamental constants of nature.
Experimental Collider Physics
Teams from KIT research at the world’s most powerful particle accelerators: the high luminosity electron-positron collider Super KEKb at KEK laboratory in Tsukuba, Japan, at the Tevatron Collider at Fermilab (USA) and at the Large Hadron Collider (LHC) at CERN, Switzerland. At the LHC which started operation in 2009, conditions are generated for reactions that took place about 10-12 seconds after the Big Bang. The CMS detector is one of four large detectors installed at the LHC to investigate these reactions.
Teams from KSETA member institute ETP have contributed since 1995 to the construction of the detector and to the data analysis which culminated in 2012 in the discovery of the Higgs Boson said to be responsible for the generation of mass. With this discovery, the Standard Model of particles and forces has been completed. The aim of the forthcoming runs is mostly to measure accurately the properties of the Higgs Boson and its interactions with other particles and to search for signs of physics beyond the Standard Model such as Dark Matter particles which may be produced at the LHC.
Theoretical Collider Physics
Information about the forces acting between elementary particles is obtained by experiments, in which particles are scattered at very high energies. Highest energies and, hence, smallest distances are reached at modern colliders, such as the LHC at Geneva. Theoretical collider physics makes predictions for these experiments and helps interpreting the data.
Matter comes in flavours providing a rich spectrum of phenomena to be studied. Doing this with highest precision for processes, that the standard theory of particle physics suppresses or forbids, allows to find hints for physics beyond the known and for mass scales beyond any direct reach. Especially the subtle breaking of symmetries and processes with quantum loops are promising. But only if theoretical wit and experimental finesse are optimally combined to assemble the splintered and scattered hints to a full mosaic of the fundamental picture.
The Belle II experiment will take data with an integrated luminosity 1000 times that of its closest competitor LHCb.
Neutrinos play a key role for our understanding of the Universe at the largest scales, as truly enormous numbers of neutrinos have been produced in the Big Bang. Their investigation touches and unifies fundamental questions of particle physics and cosmology.
To understand the role of these weakly interacting particles one has to measure the uncharted mass scale and mass hierarchy of neutrinos. The Karlsruhe Tritium Neutrino Experiment KATRIN will be the first worldwide to measure directly and in a model-independent way the mass of neutrinos with a sufficient sensitivity to determine their role as cosmic architects. But also in particle physics the neutrino properties like the mass scale measured by KATRIN provide unique access to extensions of the Standard Model of particle physics.
Computational Physics (GridKa)
The research fields of particle and astroparticle physics are not feasible without the use of high-performance computers and distributed high throughput computing infrastructures, like the Worldwide LHC Computing Grid (WLCG).
GridKa at SCC, one of 12 Tier-1 centres of WLCG, is a major hub for computing and data distribution of all four of the LHC experiments as well as other HEP experiments and Auger. In addition to huge amounts of storage and archiving capacity and compute power, GridKa provides highly available Grid services used by the various experiment collaborations.
To optimize the use of computing and storage resources, KIT develops effective algorithms and optimized software to solve physical problems in particle and astroparticle physics.
Already at the startup of the largest particle accelerator of the world, the LHC at CERN, Geneva, scientists of KCETA are working on the development of novel detectors for the next accelerator generation. It is aimed at increasing the resistance of the detector against radiation damage and at increasing the solid angle acceptance by using new cooling techniques.
For the KATRIN experiment unprecedented high vacuum systems and large superconducting magnet systems are designed and brought into operation. Locating the KATRIN experiment at KIT allows to make use of the unique expertise of the on-site Tritium Laboratory Karlsruhe (TLK), which is the only scientific laboratory equipped with a closed tritium cycle and licensed to handle the required amount of tritium.
The development of radio antennas for the detection of radio signals from air showers (LOPES) supports new promising options in the investigation of cosmic radiation. The method is optimized in prototype experiments.
We find refrigeration technology and cryotechnology in several of the research topics. They usually have the characteristic of an enabling technology in order to take advantage of special physical effects (e.g. supraconductivity)
KSETA PIs working in this field are Jürgen Becker, Beate Bornschein, , Ralph Engel, Steffen Grohmann, Andreas Haungs, Bernhard Holzapfel, Tim Huege, Bianca Keilhauer, Matthias Kleifges, Andreas Kopmann (KATRIN), Ivan Perić, Markus Roth, Oliver Sander, Rainer Stotzka, Ralf Ulrich, , Marc Weber, Sascha Wüstling (KATRIN) and Sebastian Kempf.
Accelerator Research at KARA
On the area of the Karlsruhe Institute of Technology, the Synchrotron Radiation Facility KARA is located in a hall of 5000 m2. There, electrons are accelerated in a storage ring to the energy of 2.5 GeV.
KARA is equipped with beamlines, which offer facilities for analytical research with synchrotron radiation in the spectral region between infrared/Terahertz and hard X-ray energies. Activities include hard X-ray lithographic microstructuring, spectroscopy, microscopy, diffraction, and imaging.
The KARA Accelerator Group is responsible for operation, maintainance and development of the KARA accelerator complex. This complex consists of the storage ring and its injector chain: e-gun, microtron and booster synchrotron. The Accelerator Development Program covers a variety of topics from the fields of single and multi-particle beam dynamics and optics. It includes design and study of new lattices for the storage ring as well as studies of new modes of operation like the dedicated low alpha mode for the production of short bunches.
KARA also offers a linac-based accelerator test facility called FLUTE.
The scientific topics are continuously developed. The driving forces in this dynamical process are the scientific curiosity as well as the program cycles of the funding programs mentioned above. Presently, we discuss as possible new activities the multi-messenger astroparticle physics with cosmic rays, the extended and intensified search for Dark Matter in direct collision experiments and at accelerators, the constitution of the theoretical astroparticle physics , the close interconnection of theoretical and experimental studies by the evaluation of LHC data and the application of GRID computing.