Expansion analyses on low-excitation planetary nebulae with stellar images
- Tohoku Univ., Sendai (Japan) Nobeyama Radio Observatory, Minamimaki (Japan)
The paper presents the results of analyses on the expansion characteristics of the low-excitation and unresolved planetary nebulae, M1-5, M1-9, K3-66, and K3-67. The sample nebulae are divided into two groups. The first includes the real compact planetary nebulae M1-5 and M1-9 based on their single-Gaussian profiles. The second one includes nebulae that are unresolved because of their large distances. The nebulae K3-66 and K3-67 should belong to the second group since they show the double-Gaussian components in the emission-line profiles. Relationships between expansion velocities and I(forbidden O III 5007 A)/I(H-beta) and between electron densities and expansion velocities give the basis for the above arguments and reveal that the nebulae IC 4997, Vy2-2, and M3-27 obviously are in different phases of evolution from those of other low-excitation planetary nebulae. 24 refs.
- OSTI ID:
- 5996110
- Journal Information:
- Publications of the Astronomical Society of the Pacific; (USA), Vol. 102; ISSN 0004-6280
- Country of Publication:
- United States
- Language:
- English
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