Helium shell game - nonradial g-mode instabilities in hydrogen-deficient planetary nebula nuclei

Journal Article · Tue Jul 01 04:00:00 EDT 1986 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/184701· OSTI ID:7259542

Kawaler, S D; Winget, D E; Hansen, C J

Preliminary results of fully nonadiabatic g-mode pulsation calculations for evolutionary models of hydrogen-deficient planetary nebula nuclei (PNNs) with active helium-burning shells are reported. Instabilities are found that are driven by the epsilon-mechanism at the position of the helium-burning shell. The periods of the unstable modes range from 50 to 214 s. In all models, the presence of an active nuclear burning shell demands that some g-modes are unstable. It is suggested that if hydrogen-deficient PNNs contain helium-burning shells, then they should show such pulsations. 23 references.

• Research Organization: Texas Univ., Austin; Joint Institute for Laboratory Astrophysics, Boulder, CO; Illinois Univ., Urbana
• OSTI ID: 7259542
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 306; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DWARF STARS
FLUID MECHANICS
HELIUM BURNING
HYDRODYNAMICS
MAGNETOHYDRODYNAMICS
MECHANICS
NEBULAE
OSCILLATIONS
PLANETARY NEBULAE
PULSATIONS
STAR BURNING
STAR EVOLUTION
STARS
WHITE DWARF STARS