McXtrace - An X-ray ray-trace simulation package

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

The Template_Johann_spec Instrument

Template instrument for a curved crystal Johann-spectrometer

Identification

• Site: Templates
• Author: Erik B Knudsen (erkn@fysik.dtu.dk)
• Origin: DTU Physics
• Date: Jan 2019

Description

This is a template instrument for a Johann spectrometer intended
for easy inclusion in other "real" instrument simulations.

The source is a divergent line like source which illumnates the
full crystal. The analyzer crystal itself is modelled as a single
bent crystal curved to a primary radius of 2*Rowland-radius.

To include a Johann spectrometer in an instrument the sample should be put where
source is in this template. and otherwis copy-paste.

Examples

(Test cases in bold)

• Test: L=2 dtheta_s=0 Detector: det4_I=9.5640e-05

Input parameters

Parameters in boldface are required; the others are optional.

Name	Unit	Description	Default
L	m	Length of the analyzer crystal.	0.2
r_Row	m	Radius of the Rowland circle. Also governs the crystal curvature (2*r_Row).	0.5
theta_inc	deg	Angle of incidence at the crystal centre	78.5
dtheta_s	deg	Rotation angle of the Source. To allow scanning with a pencil beam across the crystal face.	0
phi_s	deg	Opening angle of source. If 0 it is set to cover the full crystal (and some).	0

Links

• Source code for Template_Johann_spec.instr.

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

Generated for mcxtrace 3.8.4

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Last Modified: Friday, 11-Sep-2026 15:00:07 CEST