High-resolution hadronic-atom x-ray spectroscopy with cryogenic detectors

2017 Fiscal Year Final Research Report

• Project/Area Number: 26707014
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Okada Shinji 国立研究開発法人理化学研究所, 東原子分子物理研究室, 協力研究員 (70391901)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 超伝導検出器 / マイクロカロリメータ / X線分光 / エキゾチック原子 / ハドロニック原子 / K中間子 / J-PARC / 国際情報交換

Outline of Final Research Achievements

This project aims to pioneer the next-generation high-resolution x-ray spectroscopy of hadronic atoms. We use a novel cryogenic x-ray spectrometer: an array of superconducting transition-edge-sensor (TES) microcalorimeters, offering unprecedented energy resolution of less than 5 eV (FWHM) at 6 keV. The 240 pixel spectrometer array will have a large collecting area of about 20 mm^2 thanks to recent technological advances in multiplexed readout. This will open a new door to investigate kaon-nucleus strong interactions.

In 2014, a pathfinding experiment was conducted by measuring pionic-atom x rays at the PSI, and successfully demonstrated the feasibility of TES-based exotic-atom x-ray spectroscopy in a hadron-beam environment. In 2016, a commissioning experiment at the actual kaon beamline of J-PARC was performed. Based on these results, the proposed experiment (J-PARC E62) for measuring kaonic atom x-rays with TES was accepted, and the beam time was finally assigned in June 2018.

Free Research Field

ストレンジネス核物理