marley::GammaStrengthFunctionModel Class Reference

Abstract base class for models of gamma-ray strength functions. More...

#include <GammaStrengthFunctionModel.hh>

Inheritance diagram for marley::GammaStrengthFunctionModel:

Public Types
enum class	TransitionType { electric , magnetic , unphysical }
	Electromagnetic transitions in nuclei may be classified by their multipolarity (electric vs. magnetic multipole radiation)

Public Member Functions
	GammaStrengthFunctionModel (int Z, int A)
virtual double	strength_function (TransitionType type, int l, double e_gamma)=0
	Returns the gamma-ray strength function (MeV –2 \(\ell\)–1) for the requested gamma energy and multipolarity. More...
virtual double	transmission_coefficient (TransitionType type, int l, double e_gamma)=0
	Returns the gamma-ray transmission coefficient (dimensionless) for the requested gamma energy and multipolarity. More...

Static Protected Member Functions
static void	check_multipolarity (int l)
	Check that l > 0 and throw a marley::Error if it is not. More...

Protected Attributes
int	A_
	Mass number.
int	Z_
	Atomic number.

Detailed Description

Abstract base class for models of gamma-ray strength functions.

Classes derived from GammaStrengthFunctionModel may be used to simulate gamma-ray emission in situations where nuclear level data are unavailable. In particular, the HauserFeshbachDecay class uses instances of GammaStrengthFunctionModel to model the competition between gamma-ray emission and particle evaporation for highly-excited nuclear states.

Constructor & Destructor Documentation

GammaStrengthFunctionModel()

marley::GammaStrengthFunctionModel::GammaStrengthFunctionModel	(	int	Z,
		int	A
	)

Parameters

Z	Atomic number of the desired nuclide
A	Mass number of the desired nuclide

Member Function Documentation

check_multipolarity()

void marley::GammaStrengthFunctionModel::check_multipolarity ( int  l )

staticprotected

Check that l > 0 and throw a marley::Error if it is not.

Todo:

Improve error message

strength_function()

virtual double marley::GammaStrengthFunctionModel::strength_function ( TransitionType  type, int  l, double  e_gamma  )

pure virtual

Returns the gamma-ray strength function (MeV ^{–2 \(\ell\)–1}) for the requested gamma energy and multipolarity.

Parameters

type	Electric or magnetic transition
l	Multipolarity of the transition
e_gamma	Gamma-ray energy (MeV)

Implemented in marley::WeisskopfSingleParticleModel, and marley::StandardLorentzianModel.

transmission_coefficient()

virtual double marley::GammaStrengthFunctionModel::transmission_coefficient ( TransitionType  type, int  l, double  e_gamma  )

pure virtual

Returns the gamma-ray transmission coefficient (dimensionless) for the requested gamma energy and multipolarity.

The gamma-ray transmission coefficient and strength function are related via \(\text{T}_{\text{X}\ell}(\text{E}_\gamma) = 2\pi f_{\text{X}\ell}(\text{E}_\gamma)\text{E}_\gamma^{(2\ell + 1)},\) where X is the type of transition (electric or magnetic), \(\ell\) is the multipolarity, \(\text{T}_{\text{X}\ell}\) is the transmission coefficient, \(f_{\text{X}\ell}\) is the strength function, and \(\text{E}_\gamma\) is the gamma-ray energy.

Parameters

type	Electric or magnetic transition
l	Multipolarity of the transition
e_gamma	Gamma-ray energy (MeV)

Implemented in marley::WeisskopfSingleParticleModel, and marley::StandardLorentzianModel.

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The documentation for this class was generated from the following files:

• /Users/gardiner/marley/include/marley/GammaStrengthFunctionModel.hh
• /Users/gardiner/marley/src/GammaStrengthFunctionModel.cc