Faint spectrophotometric standard stars for large optical telescopes. I

The authors present spectral energy distributions over the range λλ3300 - 10000 for a set of five spectrophotometric standards four of which are white dwarfs. These stars are faint (V ≡ 15m.5), equatorial, and exhibit nearly featureless continua, so they can be observed without neutral density filters to calibrate the response of photon-counting spectrographs on large telescopes in both hemispheres.