code: def refl(scatterer, h_pol=True):
      
      return scatterer.wavelength**4/(np.pi**5*scatterer.Kw_sqr) * \
          radar_xsect(scatterer, h_pol)
docs: Reflectivity (with number concentration N=1) for the current setup.
  
      Args:
          scatterer: a Scatterer instance.
          h_pol: If True (default), use horizontal polarization.
          If False, use vertical polarization.
  
      Returns:
          The reflectivity.
  
      NOTE: To compute reflectivity in dBZ, give the particle diameter and
      wavelength in [mm], then take 10*log10(Zi).