Eur. Phys. J. Plus (2011) 126: 108
https://doi.org/10.1140/epjp/i2011-11108-7

Regular Article

Design and performance of horizontal-type neutron reflectometer SOFIA at J-PARC/MLF

¹ Neutron Science Division, High Energy Accelerator Research Organization (KEK), 203-1 Shirakata, Tokai, Naka, 319-1106, Ibaraki, Japan
² Department of Chemistry for Materials, Mie University, Tsu, Mie, Japan
³ Takahara Soft Interfaces Project, JST,ERATO, Fukuoka, Japan
⁴ Institute for Materials Chemistry and Engneering, Kyushu University, Fukuoka, Japan
⁵ Graduate School of Engineering, Hokkaido University, Sapporo, Japan
⁶ Department of Nuclear Engineering, Kyoto University, Kyoto, Japan
⁷ Research Reactor Institute, Kyoto University, Kumatori, Osaka, Japan
⁸ Nuclear Professional School, The University of Tokyo, Tokai, Ibaraki, Japan
⁹ Department of Nuclear Engineering and Management, The University of Tokyo, Hongo, Tokyo, Japan

^* e-mail: norifumi.yamada@kek.jp

Received: 30 April 2011
Revised: 5 June 2011
Accepted: 27 September 2011
Published online: 11 November 2011

Abstract

Neutron reflectometry is a powerful method for investigating the surface and interfacial structures of materials in the spatial range from nanometers to sub-micrometers. At the Japan Proton Accelerator Research Complex (J-PARC), a high-intensity pulsed neutron beam is produced with a proton accelerator at 220kW, which will be upgraded to 1MW in future. Beamline 16 (BL16) at the Materials and Life Science Experimental Facility (MLF) in J-PARC is dedicated to a horizontal-type reflectometer, and in this beamline, neutrons are transported downward at two different angles, 2.2^° and 5.7^° , relative to the horizontal. In December 2008, we started to accept the neutron beam at BL16 with the old ARISA reflectometer relocated from the KENS facility, KEK, Japan; and we have now replaced it with the brand-new reflectometer SOFIA (SOFt Interface Analyzer). With a high-flux beam and instrumental upgrade, the observable reflectivity of SOFIA reaches around 10⁻⁷ within a few hours for specimens on 3” substrates. In this paper, we will present the design and performance of the SOFIA reflectometer, and discuss some preliminary results on the device development for further upgrade.