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

The SE_example Instrument

Mockup of transmission Spin-Echo, written for PNCMI 2010 school in Delft.

Identification

• Site: Tests_polarization
• Author: Erik Knudsen, Peter Willendrup
• Origin: Risoe
• Date: June 2010

Description

This instrument shows the use of essential McStas polarisation components, including Pol_mirror, Pol_Bfield and MeanPolLambda_monitor.

Pol_mirror is used to polarize and analyze the incoming and scattered beams.
Pol_Bfield is used to define guidefields and flippers.
MeanPolLambda_montior is used to monitor beam polarisation.

Example: mcrun SE_example.instr dBz=-0.0001,0.0001 -N41 -n1e5

Examples

(Test cases in bold)

• TestScan: mcrun SE_example.instr dBz=-0.0001,0.0001 -N41 -n1e5 Detector: detector_I={41 values}

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
POL_ANGLE	deg	Reflection angle of polarizer/analyzer	2
SAMPLE	1	Flag to include (0) or exclude incoherent scatterer	0
Bguide	T	Field magnitude in guide fields	0.1
Bflip	T	Magnitude of flipper fields,	3e-4
dBz	T	Magnitude field perturbation in first guide field	0
Lam	AA	Mean wavelength of neutrons emitted from source	8
dLam	AA	Wavelength spread of neutrons emitted from source	0.8

Links

• Source code for SE_example.instr.
• Requires mcstas 1.12b (or beta). PolLambda_monitor has been modified to work (nL->nlam)

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

Generated for mcstas 3.10.0

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Last Modified: Friday, 23-Oct-2026 18:32:10 CEST