Neutron collimator with rectangular beam profile

Cussen, L.D.; Høghøj, Peter; Anderson, I. S.

doi:10.1016/s0168-9002(00)01077-9

Cited by 13 publications

(10 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fig. 2 of Cussen et al (2001) shows the measured and predicted rocking curves of the ®rst tests of a full-size re¯ecting collimator. The excellent agreement suggests that such technical dif®culties may prove to be small.…”

Section: Resultsmentioning

confidence: 99%

“…Cussen (1998) proposed a construction technique for such rectangular-pro®le collimators, exploiting today's techniques and materials. Two groups [Krist & Mezei (2000) at the Hahn Meitner Institute in Germany, and Cussen et al (2001) at the Institut Laue-Langevin in France] have independently produced working prototypes. The devices are not yet in use, seemingly because the development effort needed appears to be large.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Scan profiles for neutron spectrometers. II. Rectangular-profile elements by acceptance-diagram methods

Cussen

2003

J Appl Cryst

View full text Add to dashboard Cite

The recent development of neutron collimators with rectangular transmission pro®les (intensity versus angular divergence) extends hope of improved count rates on neutron scattering instruments. It is usually assumed that a more effective use of beam angular spread in these devices should increase count rates by about a factor of two. However, real beams have both angular and wavevector spread and both these spreads are governed by the allowed collimation. In this extended view, the gains from ideal rectangular-pro®le elements (angle ®lters) are shown to be much larger (about a factor of four). The mirror re¯ections used to achieve the rectangular pro®les in real devices complicate the resolution effects. Speci®cally, the re¯ections disturb the wavevector±angular divergence correlation in the beams, leading to unusual peak shapes characterized by triple peaks on powder diffractometers. Thus, these re¯ecting collimators are likely to be universally useful only before the monochromator and immediately preceding the detector, where wavevector± angle correlations have no effect. This reduces the potential gains to a factor of two or so. Note that the gains are as previously expected but for quite different reasons than imagined. This remains a very signi®cant gain in a ®eld where most work is intensity-limited.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Scan profiles for neutron spectrometers. II. Rectangular-profile elements by acceptance-diagram methods

Cussen

2003

J Appl Cryst

View full text Add to dashboard Cite

show abstract

“…The collimation angle is then obtained by analyzing the fitted parameters. Meister and Weckermann introduced a method for analyzing the collimation angle of a neutron Soller collimator [5], and until now many experiment results have been analyzed using this method [6][7][8]. A mathematical model for the neutron source and neutron transmission of a collimator was given according to the experiment process.…”

Section: Theorymentioning

confidence: 99%

A new method for analyzing the collimation angle of a neutron Soller collimator

Gao¹,

Liu²,

Chen³

2016

Chinese Phys. C

View full text Add to dashboard Cite

A new method for analyzing the collimation angle of a neutron Soller collimator is described. A Gaussian distribution formula is used to define the angular distribution function of the neutron source and the neutron transmission function of the Soller collimator. A relationship between the FWHM of the collimator rocking curve and the collimation angle is derived. Using this method, some rocking curve experiment results are analyzed. The results show that the new function can be a good theoretical model for fitting the experimental data, especially for the data of two collimators with different collimation angles.

show abstract

“…Each multilayer will reflect neutrons as a cylindrical concave mirror in a limited angular range determined by the multilayer length and the nominal source-mirror distance. Stacks of silicon wafers with coated reflecting and/or absorbing surfaces have already been used in neutron scattering instruments as collimators, 11,12 benders, 13 or multiple reflection focusing microguides. 14,15 More recently, Johnson and Daymond suggested the possibility of using sets of silicon-based elliptic or parabolic reflecting surfaces as a neutron lens.…”

Section: Neutron Lens By Superposition Of Glancing Reflectionsmentioning

confidence: 99%