Auxiliary class to make coordinate transformations for a specific geographical location of the detector. More...

#include <JAstronomy.hh>

Inheritance diagram for JASTRONOMY::JAstronomy:

Public Member Functions
	JAstronomy (const JGeographicalLocation &location)
	Constructor. More...

JNeutrinoDirection	getDirectionOfNeutrino (const double &t1, const JSourceLocation &pos) const
	Get direction pointing to source. More...

JSourceLocation	getLocationOfSource (const double t1, const JNeutrinoDirection &dir) const
	Get location of source. More...

const double &	getLatitude () const

const double &	getLongitude () const

Protected Attributes
double	__latitude

double	__longitude

Detailed Description

Auxiliary class to make coordinate transformations for a specific geographical location of the detector.

Note: SLALIB ref. system : (x,y,z) = (N,E,up) ANTARES ref. system for d10_c00_s00 : (x,y,z) = (N,W,up) ANTARES ref. system for real det. : (x,y,z) = (E,N,up)

Definition at line 277 of file JAstronomy.hh.

Constructor & Destructor Documentation

JASTRONOMY::JAstronomy::JAstronomy ( const JGeographicalLocation & location )

inline

Constructor.

Parameters

location location of detector

Definition at line 287 of file JAstronomy.hh.

                                                       :
       JGeographicalLocation(location)
     {}

Member Function Documentation

JNeutrinoDirection JASTRONOMY::JAstronomy::getDirectionOfNeutrino	(	const double &	t1,
		const JSourceLocation &	pos
	)		const

inline

Get direction pointing to source.

Parameters

t1	number of seconds since MJD
pos	source location

Returns: direction of neutrino

Definition at line 299 of file JAstronomy.hh.

     {
       double mjd       = t1 / NUMBER_OF_SECONDS_PER_DAY;     // [days]
 
       double longitude = getLongitude();
       double latitude  = getLatitude();
 
       // Convert current mjd (UTC) to local sidereal time, 
       // taking into account the Equation of the Equinoxes:
       // Note: LST = GMST + local longitude, where l.l. is +/- if east/west of prime meridian
 
       double gmst      = sla_gmst_ (mjd);                    // gmst = Greenwich mean sidereal time
       double eqeqx     = sla_eqeqx_(mjd);                    // Note: Equation of the Equinoxes < 1.15 secs
       double lst       = gmst + longitude + eqeqx;
       
       // Transform time-independent equatorial coordinates to time-dependent equatorial coordinates (i.e.\ ra->ha):
 
       double dec = pos.getDeclination();
       double ra  = pos.getRightAscension();
       double ha  = lst - ra;
       
       // Convert time-dependent equatorial coordinates to local horizontal coordinates:
       // Note: azimuth: [0,2pi] and elevation: [-pi,pi]
 
       double azimuth;
       double elevation;
       
       sla_de2h_(ha, dec, latitude, azimuth, elevation);
 
       double theta = -elevation + JMATH::PI/2.0;
       double phi   = -azimuth   + JMATH::PI/2.0;
 
       // invert direction
 
       theta = JMATH::PI  - theta;
       phi   = phi + JMATH::PI;
 
       if (phi > JMATH::PI)
         phi -= 2.0*JMATH::PI;
 
       return JNeutrinoDirection(theta,phi);
     }

JSourceLocation JASTRONOMY::JAstronomy::getLocationOfSource	(	const double	t1,
		const JNeutrinoDirection &	dir
	)		const

inline

Get location of source.

Parameters

t1	number of seconds since MJD
dir	direction of neutrino

Returns: source location

Definition at line 351 of file JAstronomy.hh.

     {
       double longitude = getLongitude();
       double latitude  = getLatitude();
       
       // invert direction
 
       double theta = JMATH::PI  - dir.getZenith();
       double phi   = dir.getAzimuth() - JMATH::PI;
 
       if (phi < 0.0) {
         phi += 2.0*JMATH::PI;
       }
 
       double elevation = -theta  + JMATH::PI/2.0;
       double azimuth   = -phi    + JMATH::PI/2.0;
       
       // Convert time-dependent equatorial coordinates to local horizontal coordinates:
       // Note: azimuth: [0,2pi] and elevation: [-pi,pi]
 
       double ha;
       double dec;
       
       sla_dh2e_(azimuth, elevation, latitude, ha, dec);
       
       // Get current mjd (UTC):
 
       double mjd = t1 / NUMBER_OF_SECONDS_PER_DAY;       // [days]
       
       // Convert current mjd (UTC) to local sidereal time, 
       // taking into account the Equation of the Equinoxes:
       // Note: LST = GMST + local longitude, where l.l. is +/- if east/west of prime meridian
 
       double gmst  = sla_gmst_ (mjd);                    // gmst = Greenwich mean sidereal time
       double eqeqx = sla_eqeqx_(mjd);                    // Note: Equation of the Equinoxes < 1.15 secs
       double lst   = gmst + longitude + eqeqx;
       
       // Transform time-independent equatorial coordinates to time-dependent equatorial coordinates (i.e.\ ra->ha):
 
       double ra = lst - ha;
 
       if (ra > JMATH::PI) {
         ra -= 2.0*JMATH::PI;
       }
 
       return JSourceLocation(dec, ra);
     }