Research Field Matter
The Helmholtz research field Matter explores the constituent parts of matter and the forces acting between them over completely different orders of magnitude, from the smallest units, elementary particles, to the largest structures in the universe.
Insights into Research Field Matter
Here, we present projects currently being carried out by scientists at the Helmholtz Centres.
Evidence of heavy elements in neutron star mergers
GSI Helmholtz Centre for Heavy Ion Research
In 2017, an international team of researchers announced that gravitational and electromagnetic waves originating from the merger of two neutron stars had been detected. Neutron star mergers could potentially be the astrophysical source for heavy elements such as gold, platinum, and uranium. An international collaboration headed by researchers from the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt and Columbia University in the US had already indicated that the synthesis of heavy elements in a neutron star merger process leads to the emission of a unique electromagnetic signal. The electromagnetic signal that has now been observed does in fact exhibit the predicted characteristic pattern. This confirms that the astrophysical source of the heavy elements has been found, solving one of the eleven most significant unsolved questions in the field of physics as identified by the US National Academies.
A number of observations suggest that the electromagnetic signal is generated by the radioactive decay of so-called r-process nuclei. It is estimated that the event produced approximately 0.06 solar masses of r-process material, including ten times the Earth’s mass in gold and uranium. According to the predictions of those involved in the collaboration, the light emitted by the neutron star merger would be a thousand times brighter than that produced by a nova and would reach its maximum after approximately one day. The event was therefore dubbed “kilonova.” This prediction has now also been confirmed by the observation of the counterpart of the gravitational wave of the neutron star merger in the optical and infrared range.
The r-process is the least understood element production process in the universe. Nuclei involved in the process are so rich in neutrons that it has not been possible to produce them in the laboratory thus far. The FAIR (Facility for Antiproton and Ion Research) accelerator complex, which is currently being constructed at GSI, will offer unique opportunities to produce and study the r-process nuclei. Up until its completion, the theorists at GSI will be gaging which information is key in terms of fully characterizing the electromagnetic signal of neutron star mergers and what conclusions can be drawn regarding r-process nucleosynthesis.
First experiments at the European XFEL
Deutsches Elektronen-Synchrotron DESY
A research team from DESY has successfully completed the first experiments at Europe’s new X-ray laser, the European XFEL. Their goal is to record previously unknown atomic structures and processes in real time, including those of biomolecules that are interesting from a medical perspective. The European XFEL’s very intensive, ultra-short X-ray laser flashes are a fundamental requirement for this measuring method. A high-speed detector developed at DESY enabled the researchers to capture the first structural images at an extremely high resolution.
Ambassadors from distant galaxies
Karlsruhe Institute of Technology (KIT)
Extremely high-energy cosmic particles that enter the Earth’s atmosphere have been known to exist since the early 1960s. Since then, scientists have been trying to uncover the origin of these particles and the process responsible for their high energy. Researchers at the Pierre Auger Observatory in Argentina, the world’s largest cosmic ray detector, have now proven that these particles originate outside our own galaxy. The communications and project management office of the international Pierre Auger Observatory are located at KIT.
How biomolecules protect themselves from light
Helmholtz-Zentrum Berlin für Materialien und Energie (HZB)
Together with partners from Sweden and the US, a team at HZB studied how biomolecules such as DNA protect themselves against light damage. Based on experiments at the BESSY II synchrotron source at HZB and in California, they observed that biomolecules absorb the energy from photons and release it again by ejecting a proton (hydrogen nucleus). Important bonds are preserved in the process. The observation was carried out at BESSY II using a sensitive measurement procedure known as resonant inelastic X-ray scattering (RIXS).
In Neptune, it’s raining diamonds
For the first time, an international team of researchers headed by HZDR physicist Dominik Kraus succeeded in observing in real time that the extreme pressure and high temperature in ice planets results in the splitting of hydrocarbons to form diamonds and hydrogen. They achieved this by using the LCLS X-ray laser at the Stanford Linear Accelerator Center to simulate the conditions in the interior of the cosmic giants. The researchers are planning to conduct similar experiments at the Helmholtz International Beamline for Extreme Fields (HIBEF), which HZDR is currently constructing at the European XFEL.
Friction Stir Welding in an X-ray Beam
Helmholtz-Zentrum Geesthacht Centre for Material and Coastal Research (HZG)
FlexiStir, a new type of sample environment developed at HZG, enables in situ observation of what is referred to as the friction stir welding process at a measuring station in a synchrotron beam at DESY. This makes it possible to monitor changes in the microstructure of the material via diffraction and small-angle scattering. The advanced experimental technique resulted in both a deeper understanding of the material transformation process as well as significant improvements in the process simulation. Results from this simulation are used in the construction of aircraft, among other applications.
When do atomic nuclei become unstable?
When atomic nuclei contain too many neutrons, they break apart. An international team of physicists has now developed a method that makes it possible to precisely calculate the exact point at which the nuclei first become unstable. The Jülich Nuclear Physics Institute/Institute for Advanced Simulation played a decisive role in the study, and the calculations were carried out using JUQUEEN, a Jülich supercomputer. The results offer a detailed insight into the structure of the atomic nuclei – and should help to provide a better understanding of how the elements developed following the Big Bang.