McXtrace logo

McXtrace - An X-ray ray-trace simulation package

ESRF; SAXSLAB Niels Bohr Institute DTU Physics


 Linux Installation (deb/rpm)
 Mac OSX Installation
 Unix Install (src code)
 Windows Installation

Project Status
 Project Partners
 Project People

Mailing list



Minutes of Meetings

McXtrace Art

About McXtrace



McXtrace: Chopper_simple Component

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

The Chopper_simple Component

Written by; Erik Knudsen Ideal chopper


  • Author:(Unknown)
  • Origin: Risoe
  • Date: August 2011
  • Version:(Unknown)


Ideal model of a chopper situated at Z=0. If a photon arrives at the chopper plane
at a time of t = [t0 +-n*T: t0 +-n*T +tau], where T is the period of the chopper, t0 the initial delay
and tau the opening time of the chopper, it is left untouched - otherwise it is ABSORBed. 
If on a continous source the isfirst parameter may be used. In this case the photon time is _defined_
by the chopper. In other words no photons are absorbed, the photon time is merely sampled within the chopper window.
t_rise is the rise-time of the chopper opening giving a trapezoidal shape.
Limitations: this component does not take chopper geometry into account. If isfirst only samples in the first chopper opening window.

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
t0 s Initial delay of the opening time 0
T s Period of the chopper 1
tau s Opening time of the chopper 0.1
xwidth m height of the chopper opening 0.1
yheight m width of the chopeper opening 0.1
isfirst is the chopper the first chopper on a continous source. 0
t_rise s Rise time of the chopper pulse. 0
tjit Timing jitter in terms of the opening time tau. For each ray the opening window will be shifted by a random amount within t=[-tjit*.5*tau,tjit*.5*tau] 0

Output parameters

Name Unit Description Default


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

Generated automatically by McDoc, Peter Willendrup <> / Tue Apr 28 09:59:35 2020

Last Modified: Tuesday, 28-Apr-2020 11:59:35 CEST
Search website mailinglist archive SVN repos McCode Trac