marley::Event Class Reference

Container for ingoing and outgoing momentum 4-vectors from a reaction. More...

#include <Event.hh>

Public Member Functions
	Event (double Ex=0.)
	Create an event with dummy particles.
	Event (const marley::Particle &a, const marley::Particle &b, const marley::Particle &c, const marley::Particle &d, double Ex=0.)
	Create a two-two scattering event. More...
	Event (const Event &other_event)
	Copy constructor.
	Event (Event &&other_event)
	Move constructor.
void	add_final_particle (const marley::Particle &p)
	Add a Particle to the vector of final particles.
void	add_initial_particle (const marley::Particle &p)
	Add a Particle to the vector of initial particles.
const marley::Particle &	ejectile () const
	Get a const reference to the ejectile.
marley::Particle &	ejectile ()
	Get a non-const reference to the ejectile.
double	Ex () const
	Get the excitation energy of the residue just after the initial two-body reaction.
const std::vector < marley::Particle * > &	get_final_particles () const
	Get a const reference to the vector of final particles.
std::vector< marley::Particle * > &	get_final_particles ()
	Get a non-const reference to the vector of final particles.
const std::vector < marley::Particle * > &	get_initial_particles () const
	Get a const reference to the vector of initial particles.
std::vector< marley::Particle * > &	get_initial_particles ()
	Get a non-const reference to the vector of initial particles.
Event &	operator= (const Event &other_event)
	Copy assignment operator.
Event &	operator= (Event &&other_event)
	Move assignment operator.
void	print (std::ostream &out) const
	Print this event to a std::ostream. More...
const marley::Particle &	projectile () const
	Get a const reference to the projectile.
marley::Particle &	projectile ()
	Get a non-const reference to the projectile.
void	read (std::istream &in)
	Read in this event from a std::istream. Any previous contents of this event will be deleted. More...
const marley::Particle &	residue () const
	Get a const reference to the residue.
marley::Particle &	residue ()
	Get a non-const reference to the residue.
const marley::Particle &	target () const
	Get a const reference to the target.
marley::Particle &	target ()
	Get a non-const reference to the target.
marley::JSON	to_json () const
	Create a JSON representation of this event.
void	write_hepevt (size_t event_num, std::ostream &out) const
	Write a HEPEvt record for this event to a std::ostream. Use the spacetime origin (t = 0 mm/c, x = 0 mm, y = 0 mm, z = 0 mm) as the initial position 4-vector for all particles. More...

Protected Attributes
double	Ex_
	Excitation energy (MeV) of the residue. More...
std::vector< marley::Particle * >	final_particles_
	Vector of pointers to each of the final state particles.
std::vector< marley::Particle * >	initial_particles_
	Vector of pointers to each of the initial state particles.

Detailed Description

Container for ingoing and outgoing momentum 4-vectors from a reaction.

For a two-two scattering reaction a + b → c + d, this class calls the ingoing particles the projectile (a) and target (b). The outgoing particles are called the ejectile (c) and residue (d). If the residue is a composite particle (e.g., a nucleus), then the class member Ex_ stores its excitation energy just after the two-two reaction occurred. After MARLEY simulates its de-excitation, the residue Particle object will be in its ground state, and the final_particles_ member of this class will include Particle objects representing the de-excitation products.

Note

This class manually manages memory (using the “rule of 5”) for the Particle objects that it owns. A better implementation from a modern C++ perspective would be to use vectors of std::unique_ptr<marley::Particle> objects and let those manage the memory (i.e., use the “rule of zero”). This design choice was made to ensure compatibility with ROOT 5, which cannot generate dictionaries for C++11 classes like std::unique_ptr.

Constructor & Destructor Documentation

marley::Event::Event	(	const marley::Particle &	a,
		const marley::Particle &	b,
		const marley::Particle &	c,
		const marley::Particle &	d,
		double	Ex = 0.
	)

Create a two-two scattering event.

Parameters

a	the projectile
b	the target
c	the ejectile
d	the residue
Ex	residue excitation energy (MeV) just after the two-two reaction

Member Function Documentation

void marley::Event::print

(

std::ostream &

out

)

const

Print this event to a std::ostream.

Parameters

out	The std::ostream to which this event will be written

void marley::Event::read

(

std::istream &

in

)

Read in this event from a std::istream. Any previous contents of this event will be deleted.

Parameters

in	The std::istream from which this event will be read

void marley::Event::write_hepevt	(	size_t	event_num,
		std::ostream &	out
	)		const

Write a HEPEvt record for this event to a std::ostream. Use the spacetime origin (t = 0 mm/c, x = 0 mm, y = 0 mm, z = 0 mm) as the initial position 4-vector for all particles.

Parameters

event_num	The event number to use in the output HEPEvt record
out	The std::ostream to which the HEPEvt record will be written

Todo:

Alter marley::Event::write_hepevt() so that the user can specify a vertex position 4-vector to use.

Member Data Documentation

double marley::Event::Ex_

protected

Excitation energy (MeV) of the residue.

Note

The Ex_ class member is always zero for residues that have no excited states.

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

• include/marley/Event.hh
• src/Event.cc