gov.nist.microanalysis.EPQLibrary
Class CzyzewskiMottCrossSection

java.lang.Object
  gov.nist.microanalysis.EPQLibrary.CzyzewskiMottCrossSection

public class CzyzewskiMottCrossSection
extends java.lang.Object

A simple class for loading tables of Mott cross-section values and then interpolating between them to return cross-sections. The tables are those of Czyzewski, MacCallum, Romig & Joy in J. Appl. Phys. Vol 68, No 7, 1990 as downloaded from http://pciserver.bio.utk.edu/metrology/htm/download.shtml. I have noticed that the tables for the Rb cross section may be in error. The Rb cross section has a bulge at high scattering angle. The result is too large a backscattered electron yield.

Copyright: Pursuant to title 17 Section 105 of the United States Code this software is not subject to copyright protection and is in the public domain

Company: National Institute of Standards and Technology

Version:

1.0

Author:

Nicholas W. M. Ritchie

Field Summary

static double	MaxEnergy
static int	SpecialAngleCount
static int	SpecialEnergyCount

Constructor Summary

CzyzewskiMottCrossSection(Element el)
MottCrossSection - Creates an object representing the Mott cross section for the specified element.

Method Summary

Element	getElement()
static int	getEnergyIndex(double energy) getEnergyIndex - Returns the index of the energy value that is strictly equal to or larger than the specified energy.
static double	getSpecialAngle(int index) getSpecialAngle - Gets the i-th angle which is actually represented in the tables.
static double	getSpecialEnergy(int index) getSpecialEnergy - Returns the i-th energy at which the cross-section is actually represented in the table.
double	meanFreePath(double energy) meanFreePath - Calculates the mean free path for this element at the specified element (in meters)
double	partialCrossSection(double elevation, double energy) partialCrossSection - Computes the partial cross-section for an electron of the specified energy scattered to the specified elevation.
double	partialCrossSection(double elevation, double azimuth, double energy) partialCrossSection - Computes the partial cross-section for an electron of the specified energy scattered to the specified elevation and azimuth.
java.lang.String	toString() toString
double	totalCrossSection(double energy) totalCrossSection - Calculates the total cross-section for an electron of the specified energy.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

SpecialEnergyCount

public static final int SpecialEnergyCount

See Also:

Constant Field Values

SpecialAngleCount

public static final int SpecialAngleCount

See Also:

Constant Field Values

MaxEnergy

public static final double MaxEnergy

Constructor Detail

CzyzewskiMottCrossSection

public CzyzewskiMottCrossSection(Element el)

MottCrossSection - Creates an object representing the Mott cross section for the specified element.

Parameters:

el - Element

Method Detail

toString

public java.lang.String toString()

toString

Overrides:

toString in class java.lang.Object

Returns:

String (non-Javadoc)

See Also:

Object.toString()

getElement

public Element getElement()

getSpecialEnergy

public static double getSpecialEnergy(int index)

getSpecialEnergy - Returns the i-th energy at which the cross-section is actually represented in the table.

Parameters:

index - int

Returns:

double - The energy in Joules

getSpecialAngle

public static double getSpecialAngle(int index)

getSpecialAngle - Gets the i-th angle which is actually represented in the tables.

Parameters:

index - int

Returns:

double

getEnergyIndex

public static int getEnergyIndex(double energy)

getEnergyIndex - Returns the index of the energy value that is strictly equal to or larger than the specified energy.

Parameters:

energy - double

Returns:

int

totalCrossSection

public double totalCrossSection(double energy)

totalCrossSection - Calculates the total cross-section for an electron of the specified energy.

Parameters:

energy - double - The electron energy in Joules

Returns:

double

partialCrossSection

public double partialCrossSection(double elevation,
                                  double azimuth,
                                  double energy)

partialCrossSection - Computes the partial cross-section for an electron of the specified energy scattered to the specified elevation and azimuth.

Parameters:

elevation - angle double - The angle in radians.

azimuth - double - The angle in radians.

energy - double - The energy in Joules.

Returns:

double

partialCrossSection

public double partialCrossSection(double elevation,
                                  double energy)

partialCrossSection - Computes the partial cross-section for an electron of the specified energy scattered to the specified elevation. The cross section is integrated over azimuthal angle.

Parameters:

elevation - double - The elevation angle in radians.

energy - double - The energy in Joules.

Returns:

double

meanFreePath

public double meanFreePath(double energy)

meanFreePath - Calculates the mean free path for this element at the specified element (in meters)

Parameters:

energy - double

Returns:

double