Acts::ChargeHypothesis Class Reference

Charge and momentum interpretation for arbitrarily charged particles. More...

#include <Acts/EventData/ChargeHypothesis.hpp>

Public Member Functions
constexpr	ChargeHypothesis (float absoluteCharge) noexcept
	Construct with the magnitude of the input charge.
constexpr float	absoluteCharge () const noexcept
	Get the absolute charge magnitude.
constexpr float	extractCharge (double qOverP) const noexcept
	Extract the signed charge from q/p.
constexpr double	extractMomentum (double qOverP) const noexcept
	Extract momentum magnitude from q/p.
constexpr bool	operator== (const ChargeHypothesis &rhs) const noexcept=default
	Compare for equality.
constexpr double	qOverP (double momentum, float signedQ) const noexcept
	Compute q/p from momentum and signed charge.

Detailed Description

Charge and momentum interpretation for arbitrarily charged particles.

Only a charge magnitude identical to zero is interpreted as representing a neutral particle. This avoids ambiguities that might arise from using an approximate comparison with an arbitrary epsilon.

Constructor & Destructor Documentation

ChargeHypothesis()

Acts::ChargeHypothesis::ChargeHypothesis ( float absoluteCharge )

explicitconstexprnoexcept

Construct with the magnitude of the input charge.

Parameters

absoluteCharge

The absolute value of the charge magnitude

Member Function Documentation

absoluteCharge()

float Acts::ChargeHypothesis::absoluteCharge ( ) const

constexprnoexcept

Get the absolute charge magnitude.

Returns

Absolute charge magnitude (0 for neutral particles)

extractCharge()

float Acts::ChargeHypothesis::extractCharge ( double qOverP ) const

constexprnoexcept

Extract the signed charge from q/p.

Parameters

qOverP

Charge over momentum

Returns

Signed charge with correct magnitude (0 for neutral)

extractMomentum()

double Acts::ChargeHypothesis::extractMomentum ( double qOverP ) const

constexprnoexcept

Extract momentum magnitude from q/p.

Parameters

qOverP

Charge over momentum

Returns

Momentum magnitude (handles both charged and neutral particles)

operator==()

bool Acts::ChargeHypothesis::operator== ( const ChargeHypothesis & rhs ) const

constexprdefaultnoexcept

Compare for equality.

Parameters

rhs	The ChargeHypothesis to compare to

Returns

True if the two ChargeHypothesis objects are equal, false otherwise

qOverP()

double Acts::ChargeHypothesis::qOverP ( double momentum, float signedQ ) const

constexprnoexcept

Compute q/p from momentum and signed charge.

Parameters

momentum	Particle momentum magnitude
signedQ	Signed charge (must match stored charge magnitude)

Returns

Charge over momentum (handles both charged and neutral particles)