[ Identification | Description | Examples | Input parameters | Links ]

The PSI_DMC Instrument

McStas model of the DMC powder diffractometer at PSI, CH.

Identification

• Site: PSI
• Author: Peter Willendrup (Risoe), Uwe Filges (PSI), Lukas Keller (PSI)
• Origin: PSI
• Date: May 7th, 2008

Description

McStas model of the DMC powder diffractometer at PSI, CH.

Please note that this instrument file does not include the radial collimator of DMC.
To generate the full 800-bin angle coverage at DMC, you should combine two simulations
using this instrumentfile, with SHIFT=0 and 0.1. This will displace the detector by half
a bin-width, which is a standard procedure at the DMC diffractometer

Examples

(Test cases in bold)

• Test: lambda=2.5666 Detector: Detector_I=7.5965E+02

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
lambda	AA	Choice of wavelength, affects both monochromator and source component	2.5666
R	1	Reflectivity of non-curved guides	0.87
R_curve	1	Reflectivity of curved guides	0.87
filename	str	Choice of reflection list file, e.g. from McStas data dir	"Na2Ca3Al2F14.laz"
D_PHI	deg	Focusing 'd_phi' for PowderN, see mcdoc page	6
SHIFT	deg	Rotation of detector, set to 0.1 to displace by half a bin	0
PACK	1	Powder packing factor	0.7
Dw	1	Powder Debye-Waller factor	0.8
BARNS	1	Flag to define if powder reflection file |F2| is in Barns or fm	1
SPLITS			58

Links

• Source code for PSI_DMC.instr.
• The PSI Monte-Carlo website.
• P Willendrup, U Filges, L Keller, E Farhi, K Lefmann: Validation of a realistic powder sample using data from DMC at PSI, ICNS 2005 (Physica B, 386, (2006), 1032.)

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[ Identification | Description | Examples | Input parameters | Links ]

Generated for mcstas 3.8.4

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Last Modified: Friday, 11-Sep-2026 15:00:09 CEST