@staticmethod
def make_spectra_table(nebins, spec_dict):
    """Construct the spectral values table

        Returns
        -------

        table : `astropy.table.Table`
            The table has these columns

        ref_mass : float
            The DM mass for this row in the table

        ref_chan : int
            The index of the DM interaction channel for this row
 
        ref_dnde : array
            The reference differential photon flux fpr each energy [ph / (MeV cm2 s)]

        ref_flux : array
            The reference integral photon flux for each energy [ph / (cm2 s)]

        ref_eflux : array
            The reference integral energy flux for each energy [MeV / (cm2 s)]

        """
    from astropy import table
    col_masses = table.Column(name='ref_mass', dtype=float, unit='GeV',
        data=spec_dict['mass'])
    col_chans = table.Column(name='ref_chan', dtype=int, data=spec_dict['chan']
        )
    col_dnde = table.Column(name='ref_dnde', dtype=float, shape=nebins,
        unit='ph / (MeV cm2 s)', data=spec_dict['dnde'])
    col_flux = table.Column(name='ref_flux', dtype=float, shape=nebins,
        unit='ph / (cm2 s)', data=spec_dict['flux'])
    col_eflux = table.Column(name='ref_eflux', dtype=float, shape=nebins,
        unit='MeV / (cm2 s)', data=spec_dict['eflux'])
    table = table.Table(data=[col_masses, col_chans, col_dnde, col_flux,
        col_eflux])
    return table
