摘要:

We present version 1.0 of the McStas freeware program package for neutron simulations. The package is based upon a special meta-language designed for Monte Carlo ray-tracing calculations and includes a library of spectrometer components and visualization tools. A detailed simulation of the Rise triple-axis spectrometer TASl shows good agreement with experiments. We invite neutron researchers to use this package and to contribute to the development of the component library.

ISSN:1044-8632    

DOI:10.1080/10448639908233684

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The name “neutron camel” is connected with an unusual profile of the back-face rocking curve (BFRC) discovered at the Bonse-Hart neutron double-crystal diffractometer, Oak Ridge National Laboratory (ORNL) 11. At that time, effort was focused on the problem of the low signal-to-noise ration of the neutron doublecrystal diffractometers based on triple-bounce Si(111) channel-cut crystals. This parameter for neutron instruments was about two orders of magnitude worse than for X-ray analogs, and this created a serious limitation of the Bonse-Hart technique for small-angle neutron scattering applications. After the first measurements of a rocking curve and comparison with calculations based on the Darwin [2] and Ewald [3] theories and the classical X-ray rocking curves obtained by Bonse and Hart [4], a hypothesis about parasitic neutron scattering generated inside a thick transparent channel-cut crystal was proposed [1]. According to this hypothesis, the main source of the parasitic signal is the single-bounce back-face (BF) reflection from the long wall of channelcut crystal. This hypothesis was based on dynamical diffraction studies carried out in the early 70s by C.G. Shull [5].

ISSN:1044-8632    

DOI:10.1080/10448639908233685

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:1044-8632    

DOI:10.1080/10448639908233686

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:1044-8632    

DOI:10.1080/10448639908233687

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor