Atomic hydrogen in planetary nebulae

Journal Article · Sun Mar 01 04:00:00 EST 1987 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/165086· OSTI ID:6167514

Schneider, S E; Silverglate, P R; Altschuler, D R; Giovanardi, C

The authors searched for neutral atomic hydrogen associated with 22 planetary nebulae and three evolved stars in the 21 cm line at the Arecibo Observatory. Objects whose radial velocities permitted discrimination from Galactic H I were chosen for observation. Hydrogen was detected in absorption from IC 4997. From the measurements new low limits are derived to the mass of atomic hydrogen associated with the undetected nebulae. Radio continuum observations were also made of several of the nebulae at 12.6 cm. The authors reexamine previous measurements of H I in planetary nebulae, and present the data on a consistent footing. The question of planetary nebula distances is considered at length. Finally, implications of the H I measurements for nebular evolution are discussed and it is suggested that atomic hydrogen seen in absorption was expelled from the progenitor star during the final 1000 yr prior to the onset of ionization. 68 references.

• Research Organization: Virginia Univ., Charlottesville; Perkin-Elmer Corp., Danbury, CT; Puerto Rico Univ., Rio Piedras; Arcetri, Osservatorio Astrofisico, Florence, Italy
• OSTI ID: 6167514
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 314; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
640105 -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHEMICAL COMPOSITION
COSMIC RADIO SOURCES
ELECTROMAGNETIC RADIATION
ELEMENTS
EMISSION SPECTRA
GALAXIES
HYDROGEN
INTERFEROMETRY
MILKY WAY
NEBULAE
NONMETALS
PLANETARY NEBULAE
RADIATIONS
RADIOWAVE RADIATION
SPECTRA
STAR EVOLUTION