Package xal.model.elem

Class ThickMatrix

java.lang.Object

xal.model.elem.Element

xal.model.elem.ThickElement

xal.model.elem.ThickMatrix

All Implemented Interfaces:

IComponent, IElement

public class ThickMatrix
extends ThickElement

User element representing a general beamline element. Arbitrary beamline elements are specified by providing the transfer matrix generator, elapsed time, and energy gain a priori. Note that for this element the transfer matrix, elapsed time, and energy gain are independent of any probe objects. Note also that the generator for the transfer matrix is specified, NOT the actual transfer matrix. Thus, this class should be used carefully.

This element is derived from the ThickElement base so that space charge kicks may be applied throughout the element.

Denoting the generator matrix as A, then the transfer matrix M(s) for a section of length s is given by

M(s) = e^sA

where e^A is the matrix exponential.

NOTE:

Currently the class implements the matrix exponential only to second order. Therefore

M(s) = I + sA + ½s²A² ( + O(s³) )

Author:

Christopher K. Allen

Field Summary

Fields

Modifier and Type	Field	Description
static final String	TYPE	string type identifier for all ThickMatrix objects

Fields inherited from class xal.model.elem.Element

dblNodeLen, dblNodePos

Fields inherited from interface xal.model.IElement

LIGHT_SPEED, PERMEABILITY, PERMITTIVITY, UNIT_CHARGE

Constructor Summary

Constructors

Constructor	Description
ThickMatrix()	JavaBean constructor - creates a new uninitialized instance of ThickMatrix BE CAREFUL
ThickMatrix(String strId, double dblLen)	Creates a new instance of ThickMatrix.
ThickMatrix(String strId, double dblLen, PhaseMatrix matPhiSub)	Creates a new instance of ThickMatrix.
ThickMatrix(String strId, double dblLen, PhaseMatrix matPhiSub, double dblDelW)	Creates a new instance of ThickMatrix

Method Summary

Modifier and Type	Method	Description
double	elapsedTime(IProbe probe, double dblLen)	Returns the time taken for any probe to drift through part of the element.
double	energyGain(IProbe probe, double dblLen)	Returns the energy gain imparted to any probe when going through part of the element.
void	setElapsedTime(double dblDelT)	Set the total elapsed time for all probes to propagate the entire element.
void	setEnergyGain(double dblDelW)	Set the total energy gain imparted to any probe propagating through entire element.
void	setTransferMapGenerator(PhaseMatrix matGen)	Set the transfer map generator A for the element.
PhaseMap	transferMap(IProbe probe, double dblLen)	Returns the transfer map produced by the generator matrix over the distance dblLen.

Methods inherited from class xal.model.elem.ThickElement

applyErrors, getLength, initializeFrom, isFirstSubslice, isLastSubslice, longitudinalPhaseAdvance, setLength

Methods inherited from class xal.model.elem.Element

addCloseElements, backPropagate, backPropagate, compDriftingTime, compProbeLocation, getAlignX, getAlignY, getAlignZ, getCloseElements, getHardwareNodeId, getId, getLatticePosition, getNodeLen, getNodePos, getParent, getPhiX, getPhiY, getPhiZ, getPosition, getType, getUID, print, propagate, propagate, setAlign, setAlignX, setAlignY, setAlignZ, setHardwareNodeId, setId, setParent, setPhiX, setPhiY, setPhiZ, setPosition, toString

Methods inherited from class java.lang.Object

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

Field Details

TYPE

public static final String TYPE

string type identifier for all ThickMatrix objects

See Also:

• Constant Field Values

Constructor Details

ThickMatrix

public ThickMatrix(String strId,
 double dblLen,
 PhaseMatrix matPhiSub,
 double dblDelW)

Creates a new instance of ThickMatrix

Parameters:

strId - identifier of this ThickMatrix object

dblLen - length of the element (in meters)

matPhiSub - 7x7 transfer matrix for a subelement

dblDelW - energy gain imparted of this element (in electron-volts)

ThickMatrix

public ThickMatrix(String strId,
 double dblLen,
 PhaseMatrix matPhiSub)

Creates a new instance of ThickMatrix. Energy gain for each subelement is initialized to zero.

Parameters:

strId - identifier of this ThickMatrix object

dblLen - length of the element (in meters)

matPhiSub - 7x7 transfer matrix for a subelement

ThickMatrix

public ThickMatrix(String strId,
 double dblLen)

Creates a new instance of ThickMatrix. The sub-element energy gain is initialized to zero. The sub-element transfer matrix is initialized to the 7x7 identity.

Parameters:

strId - identifier of this ThickMatrix object

dblLen - length of the element (in meters)

ThickMatrix

public ThickMatrix()

JavaBean constructor - creates a new uninitialized instance of ThickMatrix BE CAREFUL

Method Details

setElapsedTime

public void setElapsedTime(double dblDelT)

Set the total elapsed time for all probes to propagate the entire element.

Parameters:

dblDelT - elapsed time through element in seconds

setEnergyGain

public void setEnergyGain(double dblDelW)

Set the total energy gain imparted to any probe propagating through entire element.

Parameters:

dblDelW - energy gain imparted to all probes (in electron-volts)

setTransferMapGenerator

public void setTransferMapGenerator(PhaseMatrix matGen)

Set the transfer map generator A for the element. The transfer map M(s) over a distance s is then given by M(s) = Exp(s*A) where Exp() is the matrix exponential function. Thus, the map M generated by A is also a matrix.

Parameters:

matGen - transfer matrix generator (probe independent)

elapsedTime

public double elapsedTime(IProbe probe,
 double dblLen)

Returns the time taken for any probe to drift through part of the element. The value dT(dblLen) returned by this method is given by dT(dblLen) = dblLen/getLength() * dblDelT where dblDelT is the value given to #setElapsedTime.

Specified by:

elapsedTime in interface IElement

Specified by:

elapsedTime in class ThickElement

Parameters:

probe - dummy argument

dblLen - length of subsection to propagate through meters

Returns:

the elapsed time through sectionUnits: seconds

energyGain

public double energyGain(IProbe probe,
 double dblLen)

Returns the energy gain imparted to any probe when going through part of the element. The value dW(dblLen) returned by this method is given by DW(dblLen) = dblLen/getLength() * dblDelW where dblDelW is the value given to #setEnergyGain.

Specified by:

energyGain in interface IElement

Specified by:

energyGain in class ThickElement

Parameters:

dblLen - dummy argument

probe - dummy argument

Returns:

energy gain for each subelement (in electron-volts)

transferMap

public PhaseMap transferMap(IProbe probe,
 double dblLen)
                     throws ModelException

Returns the transfer map produced by the generator matrix over the distance dblLen. NOTE: Currently the transfer map returned is accurate only to order two. That is the matrix exponential function is approximated by its first three terms.

Specified by:

transferMap in interface IElement

Specified by:

transferMap in class ThickElement

Parameters:

dblLen - propagation length in meters

probe - dummy argument

Returns:

computed transfer map

Throws:

ModelException - this should not occur

See Also:

• setTransferMapGenerator(xal.tools.beam.PhaseMatrix)