STRASSE Liquid Hydrogen Target System Developed for Nuclear Structure Studies at RIKEN
Researchers at RIKEN's Nishina Center have developed a compact liquid hydrogen target system called STRASSE for studying nuclear structure through proton-induced quasi-free scattering measurements. The system features a customizable cylindrical cell up to 125 mL with thin Mylar walls and operates at 20 K with rapid cool-down capabilities to minimize experimental downtime. This advancement enables high-precision nuclear structure investigations using missing-mass and in-flight gamma-ray spectroscopy techniques at the RIBF facility.
The STRASSE (Silicon Tracker for RAdioactive nuclei Studies at SAMURAI Experiments) liquid hydrogen target system represents a specialized instrumentation development for nuclear physics research. The compact design incorporates a customizable cylindrical cell with a maximum volume of 125 mL, which increases reaction rates and luminosity for experiments. Key technical features include thin Mylar walls that minimize angular straggling of protons, and a cryogenic system optimized to operate at 20 K with cool-down times of 5 hours or less. The system is specifically engineered for proton-induced quasi-free scattering measurements in inverse kinematics, a technique used to study the structure of atomic nuclei. The rapid cool-down capability and provisions for empty-target measurements reduce experimental dead time, improving overall efficiency. This apparatus will support advanced nuclear spectroscopy studies at RIKEN's Radioactive Isotope Beam Factory (RIBF).
What's missing
The study does not discuss comparative performance metrics against previous target systems, specific experimental results or preliminary data from STRASSE operations, or the timeline for full deployment and first physics results at the RIBF facility.
What different sources said
- arXiv physicsCenter
The STRASSE liquid hydrogen target system
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