STRASSE Liquid Hydrogen Target System Developed for Nuclear Structure Studies at RIKEN
Researchers have developed a compact liquid hydrogen target system called STRASSE for use at the RIKEN Nishina Center's RIBF facility in Japan. The system is designed for proton-induced quasi-free scattering experiments in inverse kinematics, featuring a cylindrical cell of up to 125 mL and thin Mylar walls to reduce measurement errors. The instrument will enable high-precision nuclear structure studies using missing-mass and in-flight gamma-ray spectroscopy techniques.
A new liquid hydrogen target system has been developed as part of the STRASSE (Silicon Tracker for RAdioactive nuclei Studies at SAMURAI Experiments) project at the RIKEN Nishina Center in Japan. The system is purpose-built for proton-induced quasi-free scattering measurements conducted in inverse kinematics, a technique used to study short-lived radioactive nuclei. Its customizable cylindrical cell can hold up to 125 mL of liquid hydrogen, increasing reaction rates and luminosity for experiments. The cryogenic system operates at 20 Kelvin and is optimized for rapid cool-down of five hours or less, minimizing experimental downtime during empty-target calibration measurements. Thin Mylar walls are used to reduce angular straggling of protons, which is critical for measurement precision. The setup will support two complementary nuclear structure investigation methods: missing-mass spectroscopy and in-flight prompt gamma-ray spectroscopy. The paper has been accepted for publication in Nuclear Instruments and Methods in Physics Research Section A.
What's missing
The paper describes the technical design and capabilities of the instrument but does not report experimental physics results obtained with it; the scientific outcomes from its deployment at RIBF remain to be published.
What different sources said
- arXiv physicsCenter
The STRASSE liquid hydrogen target system
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