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PseudoSersicGeometry Class Reference

#include <PseudoSersicGeometry.hpp>

Inheritance diagram for PseudoSersicGeometry:
Inheritance graph
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Public Member Functions

double density (double r) const override
 
double effectiveRadius () const
 
double index () const
 
double randomRadius () const override
 
double Sigmar () const override
 
- Public Member Functions inherited from SpheGeometry
virtual double density (double r) const =0
 
double density (Position bfr) const override
 
int dimension () const override
 
Position generatePosition () const override
 
virtual double randomRadius () const =0
 
virtual double Sigmar () const =0
 
double SigmaX () const override
 
double SigmaY () const override
 
double SigmaZ () const override
 
virtual double density (Position bfr) const =0
 
virtual int dimension () const =0
 
virtual Position generatePosition () const =0
 
virtual double SigmaX () const =0
 
virtual double SigmaY () const =0
 
virtual double SigmaZ () const =0
 
- Public Member Functions inherited from SimulationItem
template<class T >
T * find (bool setup=true) const
 
template<class T >
T * interface (int levels=-999999, bool setup=true) const
 
virtual string itemName () const
 
void setup ()
 
string typeAndName () const
 
- Public Member Functions inherited from Item
 Item (const Item &)=delete
 
virtual ~Item ()
 
void addChild (Item *child)
 
const vector< Item * > & children () const
 
virtual void clearItemListProperty (const PropertyDef *property)
 
void destroyChild (Item *child)
 
virtual bool getBoolProperty (const PropertyDef *property) const
 
virtual vector< double > getDoubleListProperty (const PropertyDef *property) const
 
virtual double getDoubleProperty (const PropertyDef *property) const
 
virtual string getEnumProperty (const PropertyDef *property) const
 
virtual int getIntProperty (const PropertyDef *property) const
 
virtual vector< Item * > getItemListProperty (const PropertyDef *property) const
 
virtual ItemgetItemProperty (const PropertyDef *property) const
 
virtual string getStringProperty (const PropertyDef *property) const
 
int getUtilityProperty (string name) const
 
virtual void insertIntoItemListProperty (const PropertyDef *property, int index, Item *item)
 
Itemoperator= (const Item &)=delete
 
Itemparent () const
 
virtual void removeFromItemListProperty (const PropertyDef *property, int index)
 
virtual void setBoolProperty (const PropertyDef *property, bool value)
 
virtual void setDoubleListProperty (const PropertyDef *property, vector< double > value)
 
virtual void setDoubleProperty (const PropertyDef *property, double value)
 
virtual void setEnumProperty (const PropertyDef *property, string value)
 
virtual void setIntProperty (const PropertyDef *property, int value)
 
virtual void setItemProperty (const PropertyDef *property, Item *item)
 
virtual void setStringProperty (const PropertyDef *property, string value)
 
void setUtilityProperty (string name, int value)
 
virtual string type () const
 

Protected Member Functions

 PseudoSersicGeometry ()
 
void setupSelfBefore () override
 
- Protected Member Functions inherited from SpheGeometry
 SpheGeometry ()
 
- Protected Member Functions inherited from Geometry
 Geometry ()
 
Randomrandom () const
 
void setupSelfBefore () override
 
- Protected Member Functions inherited from SimulationItem
 SimulationItem ()
 
virtual bool offersInterface (const std::type_info &interfaceTypeInfo) const
 
virtual void setupSelfAfter ()
 
virtual void setupSelfBefore ()
 
- Protected Member Functions inherited from Item
 Item ()
 

Private Types

using BaseType = SpheGeometry
 
using ItemType = PseudoSersicGeometry
 

Private Attributes

double _bn
 
double _effectiveRadius
 
double _index
 
const double & _n
 
const double & _reff
 
double _rhon
 
Array _rv
 
Array _Xv
 

Friends

class ItemRegistry
 

Detailed Description

The PseudoSersicGeometry class is a subclass of the SpheGeometry class, and describes geometries that are a very good approximation of a Sersic density profile. This geometry, introduced by Prugniel & Simien (1997, A&A, 321,111) is an approximation of the Sersic geometry and has the advantage that the space density is known analytically rather than the density projected on the sky. The pseudo-Sersic geometry is characterized by the density profile,

ρ(r)=ρn(rreff)12n1exp[bn(rreff)1n].

The parameter bn is a dimensionless number given by

bn=2n13+4405n+4625515n2+1311148175n3.

The geometry has two free parameters: the Sersic index n and the effective radius reff.

This item type is displayed only if the Boolean expression "Level2" evaluates to true after replacing the names by true or false depending on their presence.

Constructor & Destructor Documentation

◆ PseudoSersicGeometry()

PseudoSersicGeometry::PseudoSersicGeometry ( )
inlineprotected

Default constructor for concrete Item subclass PseudoSersicGeometry : "a pseudo-Sérsic geometry" .

Member Function Documentation

◆ density()

double PseudoSersicGeometry::density ( double  r) const
overridevirtual

This function returns the density ρ(r) at the radius r. It just implements the analytical formula.

Implements SpheGeometry.

◆ effectiveRadius()

PseudoSersicGeometry::effectiveRadius ( ) const
inline

This function returns the value of the discoverable double property effectiveRadius : "the effective radius" .

This property represents a physical quantity of type "length" .

The minimum value for this property is "]0" .

◆ index()

PseudoSersicGeometry::index ( ) const
inline

This function returns the value of the discoverable double property index : "the Sérsic index n" .

The minimum value for this property is "]0.5" .

The maximum value for this property is "10]" .

The default value for this property is given by the conditional value expression "1" .

◆ randomRadius()

double PseudoSersicGeometry::randomRadius ( ) const
overridevirtual

This function returns the radius of a random position drawn from the pseudo-Sersic geometry. We just use the vector of cumulative masses stored internally.

Implements SpheGeometry.

◆ setupSelfBefore()

void PseudoSersicGeometry::setupSelfBefore ( )
overrideprotectedvirtual

This function calculates some frequently used values. The density scale ρn is set by the normalization condition that the total mass is equal to one. We easily find that

ρn=bn2n+124πreff3nΓ(2n+12).

We also set of a vector with the cumulative mass

M(r)=4π0rρ(r)r2dr

at a large number of radii. For the pseudo-Sersic model,

M(r)=P[12+2n,bn(rre)1/n]

where P(a,x) is the incomplete Gamma function.

Reimplemented from Geometry.

◆ Sigmar()

double PseudoSersicGeometry::Sigmar ( ) const
overridevirtual

This function returns the radial surface density, i.e. the integration of the density along a line starting at the centre of the coordinate system,

Σr=0ρ(r)dr.

For the pseudo-Sersic geometry, one finds

Σr=πnρ0reffbn.

Implements SpheGeometry.


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