Expected performance of time-gradient magnetic field SESANS diffractometer at pulsed reactor IBR-2

International Conference on Polarised Neutrons for Condensed Matter Investigations

Bodnarchuk, V.^1 ; Sadilov, V.^1,2 ; Manoshin, S.^1 ; Erhan, R.V.^1,3 ; Ioffe, A.^4

Joint Institute for Nuclear Research, Frank Laboratory of Neutron Physics, Joliot Curie 6, Dubna, Moscow region

141980, Russia^1

Lomonosov Moscow State University, Faculty of Physics, Leninskiye Gory 1, Moscow

119991, Russia^2

Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering, Department of Nuclear Physics, Reactorului 30, Bucharest-Magurele

077125, Romania^3

Jülich Centre for Neutron Science, Heinz Maier-Leibnitz Centre (JCNS MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, Garching

85747, Germany^4

关键词: Neutron spin echo;    Neutron wavelengths;    Pulsed reactor;    Simulation packages;    Small angle scattering;    Time gradients;    Time of flight;    Virtual experiments;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/862/1/012003/pdf
DOI  :  10.1088/1742-6596/862/1/012003

来源: IOP

【 摘 要 】

The application of the time-gradient magnetic field neutron spin-echo technique (TGF-NSE) aiming to extend the possibilities of the REFLEX reflectometer at the pulsed reactor IBR-2 (Dubna, Russia) towards a high and medium resolution small-angle scattering is considered. This technique requires the use of a linearly increasing magnetic field in the form of the sequence of saw-teeth pulses. Such a technique is well-suited to the pulsed structure of the neutron beam at the IBR-2 reactor. The wide range of neutron wavelengths employed in the time-of-flight (TOF) operation mode allows for the simultaneous coverage of a wide range of spin-echo lengths (corresponding to a wide Q-range in conventional SANS). Virtual experiments carried out using the VITESS simulation package demonstrate that such a setup at IBR-2 will allow for the coverage of the length scales from 100 Å to 6000 Å in a single instrument setting. The use of the TGF-NSE technique in the TOF mode leads to gaps in the measured SANS curves due to the jumps of magnetic field at the end of saw-teeth pulses. However, crucially, these do not harm the quality of the data. Moreover, the lost data can be retrieved by an additional measurement with a delayed start of the magnetic pulse sequence.