Scientists crack the secret of the halo cores!

Scientists crack the secret of the halo cores!

Scientists from several institutions have successfully tested a new method for analyzing halo nuclei. The group consists of researchers from Johannes Gutenberg University Mainz, Texas A&M University, Brookhaven National Laboratory, Michigan State University and the University of Surrey. This method, known as the ratio method, has been proven experimentally and published in the renowned journal Review Physics Letters published.

Halo nuclei, a class of atomic nuclei, are characterized by their size and unstable properties. An example is beryllium-11, whose half-life is only 13 seconds. These nuclei have the potential to break away from one or two neutrons, forming a diffuse halo around a compact nucleus.

The ratio method in detail

The ratio method was originally developed in 2011 by Pierre Capel, Ronald C. Johnson and Filomena M. Nunes. The aim of this method is to precisely determine the structure of the halo nuclei by analyzing the ratio of their scattering and decay angle cross sections. This allows experimental influences to be minimized, resulting in greater accuracy.

It was crucial for the experimental team to create beryllium-11 at Texas A&M University. They then collided this isotope with carbon-12. The results showed that the scattering and decay cross sections have similar characteristics, which confirmed the validity of the ratio method.

Outlook and future experiments

As part of their research, the scientists plan to also examine carbon-19. These future experiments should enable a more precise determination of the separation energy and provide valuable information about the halo structure. The associated experiment will take place at the FRIB (Facility for Rare Isotope Beams), which is considered the most powerful heavy ion accelerator and is largely operated by Michigan State University.

Additionally, data from the FRIB experiment are expected to contribute to the simultaneous measurement of elastic scattering and decay cross sections for carbon-19. This could provide important insights into the properties of carbon-18, carbon-19 and boron-18. The project is funded by the U.S. Department of Energy (DOE) and its Office of Science, which serves as the largest supporter of basic research in the physical sciences in the United States.

The ratio method thus represents a significant advance in nuclear physics as it enables improved accuracy in the analysis of unstable isotopes. The combined expertise of the participating institutions promises to shed light on fundamental questions in nuclear astrophysics and fundamental interactions.