[ Identification | Description | Input parameters | Links ]

# The `ISIS_GEM` Instrument

McStas instrument for simulating the GEM diffractometer at ISIS TS1.

## Identification

- Site: ISIS
- Author: E. Farhi, G. Cuello, M. Tucker
- Origin: ISIS
- Date: September 20, 2006

## Description

    McStas instrument for simulating GEM at ISIS TS1.
    The sample is a powder. The detector is simplified as a banana shaped one.

    The General Materials Diffractometer is a new generation neutron diffractometer
    recently constructed at the ISIS pulsed neutron source. GEM can be used to
    perform high intensity, high resolution experiments to study the structure of
    disordered materials and crystalline powders.

## Input parameters

Parameters in boldface are required; the others are optional.

Name | Unit | Description | Default
l_min | AA | Minimum wavelength produced at source | 0.1
l_max | AA | Maximum wavelength produced at source | 4.2
dist | m | Sample-detector distance (detector radius) | 1.3795
sample | string | Reflection list for powder sample | "Y2O3.laz"

## Links

- Source code for `ISIS_GEM.instr`.
- The ESS Instrument workshops website.
- The GEM instrument at ISIS

[ Identification | Description | Input parameters | Links ]