org.lcsim.recon.tracking.trfdca

Class DistSurface

java.lang.Object

org.lcsim.recon.tracking.trfutil.RootFindLinear

org.lcsim.recon.tracking.trfdca.DistSurface

All Implemented Interfaces:

RootFinder

public class DistSurface
extends RootFindLinear

DistSurface.java This is a class for finding the propagation distance of a track to an arbitrary surface in a uniform magnetic field. The constructor arguments include the initial track position (x, y, z), direction (phid, tlam), the helix rate or curvature wc (abs(wc) = cos(lambda) / radius), the destination surface and limits (smin, smax). The limits are used to resolve multiple solution ambiguities (otherwise the nearest solution is used). Return value status codes can be found in trfutil/RootFindLinear.h

Version:

1.0

Author:

Norman A. Graf

Field Summary

Fields

Modifier and Type	Field and Description
private double	_b
private double	_clam
private boolean	_dca
private double	_phi
private double	_phib
private double	_phid
private double	_r
private double	_slam
private double	_smax
private double	_smin
private Surface	_srf
private double	_tlam
private double	_wc
private double	_x
private double	_y
private double	_z

Fields inherited from class org.lcsim.recon.tracking.trfutil.RootFindLinear

INVALID_FUNCTION_CALL, INVALID_LIMITS, OK, OUT_OF_RANGE, TOO_MANY_ITERATIONS

Constructor Summary

Constructors

Constructor and Description
DistSurface(double x, double y, double z, double phid, double tlam, double wc, Surface srf) Creates a new instance of DistSurface using the initial track parameters and the destination surface.
DistSurface(double x, double y, double z, double phid, double tlam, double wc, Surface srf, double smin, double smax) Creates a new instance of DistSurface using the initial track parameters and the destination surface.

Method Summary

Methods

Modifier and Type	Method and Description
double	derivative(double s) Calculate derivative wrt s of function calculated by method evaluate.
StatusDouble	distance() Find distance to the destination surface.
StatusDouble	distanceToCylinder() Return distance to cylinder surface.
StatusDouble	distanceToStraightDca() Find distance to straight dca surface.
StatusDouble	distanceToTiltedDca() Find distance to tilted dca surface.
StatusDouble	evaluate(double s) Evaluate function whose zero gives distance to tilted dca surface.
String	toString() String representation of this object.

Methods inherited from class org.lcsim.recon.tracking.trfutil.RootFindLinear

solve

Methods inherited from class java.lang.Object

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

Field Detail

_x

private double _x

_y

private double _y

_z

private double _z

_phid

private double _phid

_tlam

private double _tlam

_wc

private double _wc

_srf

private Surface _srf

_smin

private double _smin

_smax

private double _smax

_dca

private boolean _dca

_r

private double _r

_phi

private double _phi

_slam

private double _slam

_clam

private double _clam

_b

private double _b

_phib

private double _phib

Constructor Detail

DistSurface

public DistSurface(double x,
           double y,
           double z,
           double phid,
           double tlam,
           double wc,
           Surface srf)

Creates a new instance of DistSurface using the initial track parameters and the destination surface.

Parameters:

x - track x position

y - track y position

z - track z position

phid - Azimuth (phi) of track momentum vector.

tlam - Latitude (tangent(lambda) of track momentum vector.

wc - Parametric cyclotron frequency (rad/cm).

srf - Destination surface.

DistSurface

public DistSurface(double x,
           double y,
           double z,
           double phid,
           double tlam,
           double wc,
           Surface srf,
           double smin,
           double smax)

Creates a new instance of DistSurface using the initial track parameters and the destination surface.

Parameters:

x - track x position

y - track y position

z - track z position

phid - Azimuth (phi) of track momentum vector.

tlam - Latitude (tangent(lambda) of track momentum vector.

wc - Parametric cyclotron frequency (rad/cm).

srf - Destination surface.

smin - Minimum allowed distance.

smax - Maximum allowed distance.

Method Detail

distance

public StatusDouble distance()

Find distance to the destination surface.

Returns:

Distance with status.

evaluate

public StatusDouble evaluate(double s)

Evaluate function whose zero gives distance to tilted dca surface.

Parameters:

s - Distance parameter.

Returns:

Function value with success status.

derivative

public double derivative(double s)

Calculate derivative wrt s of function calculated by method evaluate.

Parameters:

s - Distance parameter.

Returns:

Function derivative.

distanceToStraightDca

public StatusDouble distanceToStraightDca()

Find distance to straight dca surface.

Returns:

Distance with success status.

distanceToTiltedDca

public StatusDouble distanceToTiltedDca()

Find distance to tilted dca surface.

Returns:

Distance with status.

distanceToCylinder

public StatusDouble distanceToCylinder()

Return distance to cylinder surface.

Returns:

Distance with status.

toString

public String toString()

String representation of this object.

Overrides:

toString in class Object

Returns:

String representation of this object.