CONTINUOUS ENERGY DISTRIBUTION

Oke (1970) carried out photoelectric spectrophotometry of 0805+046 and obtained the absolute spectral-energy distribution from 3220 to 9000. It was found that there was a drop of intensity by a factor of 2 at 3420. We identify this drop with the helium discontinuity at 3422 (the ionization limit from the 2³P state of helium). This helium discontinuity was first observed by Popper (1947) in the helium-rich star HD 124448.

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