A compact TOF-SANS using focusing lens and very cold neutrons |
| |
Authors: | Masako Yamada Yoshihisa IwashitaToshiji Kanaya Norifumi L. YamadaHirohiko M. Shimizu Kenji MishimaMasahiro Hino Masaaki KitaguchiKatsuya Hirota Peter GeltenbortBruno Guerard Giuliana ManzinKen Andersen Jyotsana LalJohn M. Carpenter Markus BleuelShane J. Kennedy |
| |
Affiliation: | a ICR, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan b KEK, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan c KURRI, 2-1010 Kumatori, Osaka 590-0494 Japan d RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan e Institut Laue-Langevin, 6 Rue Jules Horowitz, B.P.156, F-38042 Grenoble Cedex 9, France f Biosciences Division, ANL, IL 60439, USA g APS Engineering Support Division, ANL, IL 60439, USA h Reactor Institut Delft TU, Mekelweg 15, 2629 JB Delft, The Netherlands i Bragg Institute, ANSTO, Lucas Heights, NSW 2234, Australia |
| |
Abstract: | We are developing a high-resolution small angle neutron scattering instrument for very cold neutrons (VCN). Our concept includes a magnetic lens for focusing of the beam at the detector plane. The lens consists of one permanent-magnet sextupole array rotating outside another stationary sextupole array, to focus a pulsed white beam of neutrons. Thus the instrument operates in time of flight mode. The prototype magnetic lens has a bore of 15 mm diameter and length of 66 mm, producing a magnetic field gradient oscillating from 1.5×104 to 5.9×104 T/m2, with frequency ≤25 Hz. A torque-canceling magnet around the lens suppresses the torque of rotation from the outer array to 1/3.We have demonstrated the performance of the lens, over wavelength range from 30 to 48 Å, on the PF2-VCN beam line at the Institut Laue-Langevin, France. The focused beam image was the same size as the source, without chromatic aberration, with focal length of 1.14 m. We also studied the performance of this configuration for high-resolution SANS, in a compact geometry (just 5 m long). The measurable q range of this system was 0.009 Å−1≤q≤0.3 Å−1 or 0.004 Å−1≤q≤0.08 Å−1 for sample to detector distances of 100 and 465 mm, respectively. Here, we present the results of our lens characterization study along with the SANS results on a tri-block copolymer (F127 Pluronic) and on a stretched polymer blend (with the Shish-Kebab structure). |
| |
Keywords: | Focusing lens Rot-PMSx Pulsed neutron beams TOF High resolution Compact instrument VCN Focusing-SANS |
本文献已被 ScienceDirect 等数据库收录! |
|