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The mid-infrared range is an important spectrum range where materials exhibit a characteristic response corresponding to their molecular structure. A free-electron laser (FEL) is a promising candidate for a high-power light source with wavelength tunability to investigate the nonlinear response of materials. Although the self-amplification spontaneous emission (SASE) scheme is not usually adopted in the mid-infrared wavelength range, it may have advantages such as layout simplicity, the possibility of producing a single pulse, and scalability to a short-wavelength facility. To demonstrate the operation of a mid-infrared SASE FEL system in an energy recovery linac (ERL) layout, we constructed an SASE FEL setup in cERL, a test facility of the superconducting linac with the ERL configuration. Despite the adverse circumstance of space charge effects due to the given boundary condition of the facility, we successfully established the beam condition at the undulators and observed FEL emission at a wavelength of 20 μm. The results show that the layout of cERL has the potential for serving as a mid-infrared light source.

Novel horizontal-type time-of-flight neutron reflectometer SOFIA (SOFt Interface Analyzer) was installed in BL 16 of Materials and Life Science Experimental Facility at the Japan Proton Accelerator Research Complex (J-PARC). The design and performance of SOFIA reflectometer was described based on the preliminary results of the neutron reflectivity (NR) measurements of deuterated polystyrene (d-PS) thin films, Langmuir–Blodgett film and at deuterium oxide/ polymer brush interfaces. Time-resolved in-situ NR measurement at 1-min intervals was also demonstrated to observe interfacial mixing of d-PS on the PS brush surface during annealing.

We are developing a fiber type two-dimentional (2-D) position-sensitive detector having a spatial resolution less than 0.5 mm in order to use it in the time-of-flight (TOF) measurements. The detector performance was examined, and some experiments on the TOF radiography were performed using this detector. The results indicated that the detector could be applied successfully to the TOF measurement and that the TOF radiography was very useful since it gave more informative data than those obtained by the conventional radiography using a broad energy band.

In 2011, two SR sources of KEK, PF-ring and PF-AR, needed to change the operation schedule because of the unprecedented earthquake on March 11. Though the injector linac and the storage rings suffered a serious damage, temporary recovery was accomplished quickly and the trial operation started in May. The regular user operation could be resumed in October 2011. In the restoration work after the earthquake, some old vacuum components were removed from PF-ring. This work fortunately brought an effect of settling the quadrupole-mode longitudinal instability. For the top-up injection of PF-ring, the pulsed sextupole magnet has been used instead of the conventional kicker magnets since 2011. The hybrid-fill mode in place of the single-bunch mode has become available. Recently, the 10-Hz orbit switching for the tandem circularly polarized undulators has been developed for the user operation.

A remote-controlled neutron collimator system and a 2-dimensional movement stand have been developed for beam tests of neutron detectors Both collimator system and movement stand employ motorized linear stages.Each motor driver is controlled by one microcomputer, and thus a PC based control program allows users to control the whole axes simultaneously.

To gain in intensity and realize a grazing-incidence small-angle scattering (GISAS) measurement on a pulsed neutron reflectometer, we are now developing focusing devices using a cylindrically bent supermirror coated on a flat float glass substrate. They have been characterized at pulsed neutron sources, and we successfully focused neutron beam into about 1mm width in either vertical or horizontal direction using the bent mirror with the focal distance of about 4 m.

A novel neutron reflectometer with horizontal geometry will be established at BL16 in Materials and Life Science Experimental Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC) as a successor of a reflectometer ARISA-II. ARISA-II corresponding to a single neutron beam downward at 2.22 deg has achieved off-specular and time-resolved reflectivity measurements. The novel reflectometer is designed so as to receive two tilted neutron beams (2.22 & 5.71 deg), which gives us an opportunity in investigation on a free liquid surface. The reflectometer can provide a micro-sized beam by slit collimation and obtain a fair reflectivity with small sample area. Also, T0 chopper and neutron focusing mirror are newly introduced. The T0 chopper can suppress the background due to fast neutrons. The focusing mirror produces further reduction of measurement time not only for specular reflection by focusing neutrons on a sample, but also grazing incidence small-angle neutron scattering (GISANS) measurements by focusing on a detector.

Super High Resolution Powder Diffractometer, SuperHRPD, is located at about 100 m from a thin side of a decoupled poisoned moderator at the Materials and Life Science Experimental Facility in the Japan Proton Accelerator Research Complex. The first neutron was produced successfully from a spallation neutron source in J-PARC in the end of May of 2008, and SuperHRPD has achieved the world best resolution Δ d / d = 0.035% in June using the existing Sirius 1) chamber. In the summer of 2009, a new SuperHRPD chamber was installed aiming at increasing the detector solid angle and expanding d -range / Q -range, with at most 1500 one-dimensional 3 He position-sensitive detectors of 1/2 inch in diameter. The on-beam commissioning of the new SuperHRPD was started in the autumn of 2009.