Source code for pystellibs.kurucz

import numpy as np
from .stellib import AtmosphereLib
from .config import libsdir
from .simpletable import SimpleTable
try:
    from astropy.io import fits as pyfits
except ImportError:
    import pyfits


class Kurucz(AtmosphereLib):
    """
    The stellar atmosphere models by Castelli and Kurucz 2004 or ATLAS9

    * LTE
    * PP
    * line blanketing
    """
    def __init__(self, *args, **kwargs):
        self.name = 'Kurucz 2004'
        self.source = libsdir + '/kurucz2004.grid.fits'
        self._load_()
        AtmosphereLib.__init__(self, *args, **kwargs)

    def _load_(self):
        with pyfits.open(self.source) as f:
            # load data
            self._getWaveLength_(f)
            self._getTGZ_(f)
            self._getSpectra_(f)
            self._getWaveLength_units(f)

    def _getWaveLength_units(self, f):
        self.wavelength_unit = 'angstrom'

    def _getWaveLength_(self, f):
        self._wavelength = f[0].data[-1]

    def _getTGZ_(self, f):
        self.grid = SimpleTable(f[1].data)
        self.grid.header.update(f[1].header.items())
        self.grid.header['NAME'] = 'TGZ'

    def _getSpectra_(self, f):
        self.spectra = f[0].data[:-1]

    def bbox(self, dlogT=0.05, dlogg=0.25):
        """ Boundary of Kurucz 2004 library

        Parameters
        ----------
        dlogT: float
            log-temperature tolerance before extrapolation limit

        dlogg: float
            log-g tolerance before extrapolation limit

        Returns
        -------
        bbox: ndarray
            (logT, logg) edges of the bounding polygon
        """
        bbox = [(3.54406 - dlogT, 5.000 + dlogg),
                (3.55403 - dlogT, 0.000 - dlogg),
                (3.778, 0.000 - dlogg),
                (3.778 + dlogT, 0.000),
                (3.875 + dlogT, 0.500),
                (3.929 + dlogT, 1.000),
                (3.954 + dlogT, 1.500),
                (4.146, 2.000 - dlogg),
                (4.146 + dlogT, 2.000),
                (4.279 + dlogT, 2.500),
                (4.415 + dlogT, 3.000),
                (4.491 + dlogT, 3.500),
                (4.591 + dlogT, 4.000),
                (4.689 + dlogT, 4.500),
                (4.699 + dlogT, 5.000 + dlogg),
                (3.544 - dlogT, 5.000 + dlogg) ]

        return np.array(bbox)

    @property
    def logT(self):
        return self.grid['logT']

    @property
    def logg(self):
        return self.grid['logg']

    @property
    def Teff(self):
        return self.grid['Teff']

    @property
    def Z(self):
        return self.grid['Z']

    @property
    def logZ(self):
        return self.grid['logz']