ATAtmosphere.h

Go to the documentation of this file.

//# ATAtmosphere.h: Model of atmospheric opacity
//# Copyright (C) 2004
//# Associated Universities, Inc. Washington DC, USA.
//#
//# This library is free software; you can redistribute it and/or modify it
//# under the terms of the GNU Library General Public License as published by
//# the Free Software Foundation; either version 2 of the License, or (at your
//# option) any later version.
//#
//# This library is distributed in the hope that it will be useful, but WITHOUT
//# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
//# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
//# License for more details.
//#
//# You should have received a copy of the GNU Library General Public License
//# along with this library; if not, write to the Free Software Foundation,
//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
//#
//# Correspondence concerning AIPS++ should be addressed as follows:
//#        Internet email: aips2-request@nrao.edu.
//#        Postal address: AIPS++ Project Office
//#                        National Radio Astronomy Observatory
//#                        520 Edgemont Road
//#                        Charlottesville, VA 22903-2475 USA
//#
//#---------------------------------------------------------------------------

#ifndef ATNF_ATATMOSPHERE_H
#define ATNF_ATATMOSPHERE_H

//  includes
#include <casa/aips.h>
#include <casa/Arrays/Vector.h>
//#include <complex>
#include <casa/namespace.h>
namespace casa {

class ATAtmosphere {
public:
  explicit ATAtmosphere(Double wvScale = 1540., Double maxAlt = 10000.0, Int nLayers = 50);
   
  ATAtmosphere(Double temperature, Double pressure, Double humidity, Double lapseRate = 0.0065, 
               Double wvScale = 1540., Double maxAlt = 10000.0, Int nLayers = 50);
   
  void setWeather(Double temperature, Double pressure, Double humidity);

  void setObservatoryElevation(Double elev);

  Double zenithOpacity(Double freq) const;

  Vector<Double> zenithOpacities(const Vector<Double> &freqs) const;
  
  Double opacity(Double freq, Double el) const;

  Vector<Double> opacities(const Vector<Double> &freqs, Double el) const;
          
protected:
  void recomputeAtmosphereModel();
  
  Int nLayers() const;
  
  static Double wvSaturationPressure(Double temperature);
   
  static DComplex dryRefractivity(Double freq, Double temperature, 
                     Double pDry, Double pVapour);
  
  static DComplex vapourRefractivity(Double freq, Double temperature, 
                     Double pDry, Double pVapour);
      
private:
  
  // heights of all model layers
  Vector<Double> itsHeights;
  
  // temperatures of all model layers
  Vector<Double> itsTemperatures;
  
  // partial pressures of dry component for all model layers
  Vector<Double> itsDryPressures;
  
  // partial pressure of water vapour for all model layers
  Vector<Double> itsVapourPressures;
  
  // ground level temperature (K)
  Double itsGndTemperature;
  
  // sea level pressure (Pascals)
  Double itsPressure;
  
  // ground level humidity (fraction)
  Double itsGndHumidity;
  
  // lapse rate (K/m)
  Double itsLapseRate;
  
  // water vapour scale height (m)
  Double itsWVScale;
  
  // altitude of the highest layer of the model (m)
  Double itsMaxAlt;
  
  // observatory elevation (m)
  Double itsObsHeight;
};

} // namespace casa

#endif // #ifndef ATNF_ATATMOSPHERE_H