K. Kasami

Absorption of scintillation light in a 100 l liquid xenon γ-ray detector and expected detector performance

An 800L liquid xenon scintillation

LN2-free Operation of the MEG Liquid Xenon Calorimeter by using a High-power Pulse Tube Cryocooler

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Test Results of Superconducting Combined Function Prototype Magnets for the J-PARC Neutrino Beam Line

ray detector is being developed for the MEG experiment which will search for

Development of a High‐Power Coaxial Pulse Tube Refrigerator for a Liquid Xenon Calorimeter

\mu^+\to\mathrm{e}^+\gamma

High-Power Pulse Tube Cryocooler for Liquid Xenon Particle Detectors

decay at the Paul Scherrer Institut. Absorption of scintillation light of xenon by impurities might possibly limit the performance of such a detector. We used a 100L prototype with an active volume of 372x372x496 mm

Performance Tests of Superconducting Combined Function Magnets in the First Full-Scale Prototype Cryostat for the J-PARC Neutrino Beam Line

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Magnetic Field Measurement System in Superconducting Combined Function Magnets for the J-PARC Neutrino Beam Line

to study the scintillation light absorption. We have developed a method to evaluate the light absorption, separately from elastic scattering of light, by measuring cosmic rays and

Cryogenic characteristics of a large thin superconducting solenoidal magnet cooled by forced two-phase helium

\alpha

PERFORMANCE OF A LIQUID XENON CALORIMETER CRYOGENIC SYSTEM FOR THE MEG EXPERIMENT

sources. By using a suitable purification technique, an absorption length longer than 100 cm has been achieved. The effects of the light absorption on the energy resolution are estimated by Monte Carlo simulation.

Pressure drop of two-phase helium flowing in a large solenoidal magnet cooling path and a long transfer line

A high‐power coaxial pulse tube cryocooler, originally developed in KEK and technology‐transferred to Iwatani Industrial Gases Corp (IIGC), has been installed in a large liquid xenon calorimeter to evaluate liquid nitrogen‐free (LN2‐free) operation of the rare μ‐particle decay experiment (MEG). Features of this pulse tube cryocooler include the cold‐end heat exchanger, designed with sufficient surface area to ensure high‐power cooling, and a cylindrical regenerator placed inside the pulse tube giving compact design and ease of fabrication. This production‐level cryocooler provides a cooling power of ∼200 W at 165 K, using a 6 kW Gifford‐McMahon (GM)‐type compressor. The paper describes the detailed configuration of the cryocooler, and the results of the continuous LN2‐free operation of the large prototype liquid xenon calorimeter, which ran for more than 40 days without problems.