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&DETECT

 

This record is used to describe detector specific parameters. In version 1.2 up to 5 different x-ray and electron detectors may be specified. The detector locations may be adjusted in the &MSETUP namelist.

EDTHSZ --- Solid Angle of Acceptance (Electron)

In Sesame 1.2 electron detectors (analysers) are assumed to be annular. This variable specifies the polar angle spread of acceptance of the detector. A minimum and a maximum value is to be specified.
Example: For a CMA with an angular spread of specify :
EDTHSZ = 39,45

ENFWHM --- Reference Energy for FWHM

This variable specifies a reference energy in eV at which the energy resolution is determined by the full width at half maximum value specified by means of the FWHM variable. According to the equation in Chapter 6.3 the energy-dependent resolution can be calculated for all x-ray peaks. The index of ENFWHM refers to the detector number. The default value of 5899 eV corresponds to the line. For further information see Chapter 6.3.

FEDTRN --- Transmission of Analyser (Electron)

With FEDTRN files containing the energy dependent transmission curve of the electron analyser can be specified. The file format is analog to the format described for FEDEFF. In the current version a maximum of 50 datapoints can be specified. During simulation transmission of the analyser is linear interpolated to obtain values intermediate to the specified energies. Caution: transmission is cut off at maximum and minimum specified energy value. If no transmission is specified, transmission is assumed to be unity at all energies (default). For further information see also Chapter 6.4.

FWHM --- Full Width at Half Maximum

This variable specifies the full width at half maximum at the reference energy defined by means of the ENFWHM variable. According to the equation in Chapter 6.3 the energy-dependent resolution can be calculated for all x-ray peaks. The index of FWHM refers to the detector number. The default value is 150 and corresponds to the energy resolution of a common energy-dispersive x-ray detector at the energy of the line. For further information see Chapter 6.3.

SOLIDA --- Solid Angle of Detection

This variable specifies the solid angle of detection in steradians. The index of SOLIDA refers to the detector number. For further information see Chapter 6.3.

XDTYPE --- X-ray Detector Type

This variable specifies the x-ray detector type. Energy-dispersive or wavelength-dispersive detector systems may be chosen. The index of XDTYPE refers to the detector number. The default value refers to an energy-dispersive detector. For further information see Chapter 6.3.

XFDEFF --- File Name for X-ray Detector Efficiency

This variable specifies the file name of an ASCII file containing the x-ray detector efficiency. The format of this file is: 1. column: Energy 2. column: Detector Efficiency. Comment lines must show a ''#'' as the first character of the line (see also Chapter 6.3).

XLAYDN --- X-Ray Detector Layer Density

This variable specifies the densities in of all layers of an x-ray Si(Li)-detector, including the detector window and the active area (see also Chapter 6.3).

XLAYMAT --- X-Ray Detector Layer Materials

This variable specifies the compositions of the x-ray detector layers. XLAYMAT is exactly defined according to ATMAT, the array for specifying the target composition, in the &TARGET namelist. XLAYMAT contains the chemical abbreviations of all elements of the detector layers and their relative fractions. The chemical abbreviations in one layer as well as the strings describing different layers must be separated by commas ( Note: strings must be enclosed by single quotes!). Relative fractions of elements in one layer must, if necessary at all, be specified right after the corresponding chemical abbreviation without a blank, comma or any other character inbetween. XLAYMAT(2,3)='AL2,O3', for instance, means that the 3rd layer of detector number 2 consists of two parts aluminum and three parts oxygen. The relative fractions in each region will be automatically normalized to unity. This means 'AL2,O3' and AL0.4,O0.6 is equivalent.

XLAYTH --- X-Ray Detector Layer Thicknesses

This variable specifies the thicknesses of all layers of an x-ray detector system in microns, including the detector window and the active area. The last entry in the XLAYTH array with a value greater than zero is considered to describe the active area. The detector efficiency is calculated according to Beer's law (see Chapter 6.3).



next up previous contents
Next: &OUTPUT Up: Input Records Previous: &INSTR



Horst Wagner
Tue Mar 19 10:24:55 MET 1996