Bibcode
Cuesta, L.; Phillips, J. P.
Referencia bibliográfica
Astronomy and Astrophysics (ISSN 0004-6361), vol. 270, no. 1-2, p. 379-392.
Fecha de publicación:
3
1993
Número de citas
12
Número de citas referidas
7
Descripción
We have undertaken high resolution spectroscopy and IR photometry of the
extended planetary nebula Sh 2-71. As a consequence, we note evidence
for a discoidal expanding emission region size about 100 arcsec, tilted
to the line of sight, and enveloping a core high-excitation source
associated with velocities about +/- 500 km/s. Both NIR and optical
continua are consistent with the presence of a high temperature central
star with about 1300 solar luminosities, together with a very much
cooler companion with spectral type A7V, while there is also evidence
for core densities not less than 21,000/cu cm, high emission measures
about 1.6 10 exp 6 pc cm exp -6 and, in all probability, Balmer line
self-absorption. It is proposed that high velocities in the core result
from the bipolar expulsion of gas near the central star, perhaps
collimated by the enveloping disk. Such results may be explained if the
central star represents one component of a short-period binary, with
mass-loss primarily deriving from a much cooler, lower luminosity
companion.