Bulk Micromegas Detector Characterized for Nuclear Astrophysics Time Projection Chamber
Researchers at the Saha Institute of Nuclear Physics have experimentally characterized a bulk Micromegas detector for use in an active target Time Projection Chamber designed to study the Hoyle state of carbon-12. The detector was tested with alpha particles and X-rays using two different gas mixtures, with results compared to hydrodynamic transport simulations. The successful validation of both the detector performance and numerical model supports its use in upcoming nuclear astrophysics experiments measuring decay branching ratios.
Scientists have completed experimental characterization of a bulk Micromegas detector intended for the Saha Active Target TPC (SAT-TPC), a specialized instrument under development for nuclear astrophysics research. The detector was tested using 5.9 keV X-rays and 5.48 MeV alpha particles from radioactive sources, with performance evaluated across two gas mixtures: Ar + CO₂ (90:10) and Ar + i-C₄H₁₀ (95:5) at atmospheric pressure. Researchers employed a hydrodynamic transport model to simulate the charge-deposit profile of alpha-particle tracks on the Micromegas readout and compared these simulations to experimental measurements. The good agreement between experimental data and numerical predictions validated both the detector's suitability for the SAT-TPC prototype and the accuracy of the hydrodynamic modeling approach. This work supports the detector's application in measuring the branching ratio of direct and sequential decay modes of the Hoyle state in carbon-12, an important target for understanding stellar nucleosynthesis.
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- arXiv physicsCenter
Experimental Characterization of Bulk Micromegas for Development of Active Target Time Projection Chamber for Nuclear Astrophysics Studies
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