Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-30T23:26:58.946Z Has data issue: false hasContentIssue false

Dynamical Structures of Planetary Nebulae — Models Against Observations

Published online by Cambridge University Press:  07 August 2017

H. Marten
Affiliation:
1Institut für Theoretische Physik und Sternwarte der Universität Kiel Olshausenstr. 40, D-2300 Kiel, Germany
K. Gesicki
Affiliation:
2Copernicus Astronomical Center, Laboratory of Astrophysics ul. Chopina 12/18, 87-100 Toruń, Poland
R. Szczerba
Affiliation:
2Copernicus Astronomical Center, Laboratory of Astrophysics ul. Chopina 12/18, 87-100 Toruń, Poland

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Hydrodynamical calculations of Planetary Nebulae (PNe) over 25000 yrs of evolution which include timedependent effects of ionization as well as variable central stars winds and parameters consistent with stellar model calculations show a great variety of velocity and density structures which strongly deviate from the often assumed “homogeneous shells, expanding with constant velocities” (Marten & Schönberner, 1991, hereafter MS). By means of a static photoionization code we calculate the surface brightness in the 10 most prominent nebular emission lines for density structures of the model sequence “VS” as given by MS. The obtained radial emissivities are used together with the velocity and temperature structure of the ionized gas to calculate (thermally broadened) line profiles in order to derive “measured” expansion velocities. We compare the theoretical surface brightnesses with observations and demonstrate some difficulties in the interpretation of nebular expansion velocities, expansion distances and ages.

Type
IV. Planetary Nebulae Connection: Evolution from the AGB
Copyright
Copyright © Kluwer 1993 

References

Balick, B., 1987, AJ 94, 671 Google Scholar
Balick, B., 1992, these proceedings Google Scholar
Frank, A., 1992, these proceedings Google Scholar
Frank, A., Balick, B., Riley, J., 1990, AJ 100, 1903 Google Scholar
Heap, S., 1992, these proceedings Google Scholar
Marten, H., Schönberner, D., 1991, A&A 248, 590 Google Scholar
Terzian, Y., 1992, these proceedings Google Scholar