Expansion patterns and parallaxes for planetary nebulae
نویسندگان
چکیده
منابع مشابه
Hubble space telescope expansion parallaxes of the planetary nebulae
We have combined two epochs of Hubble Space Telescope WFPC2 imaging data with ground-based expansion velocities to determine distances to three planetary nebulae (NGC 6578, NGC 6884, and IC 2448). We used two variants of the expansion parallax technique—a gradient method and a magnification method— to determine the distances. The results from the two methods agree to within the errors. A fourth...
متن کاملOn expansion parallax distances for planetary nebulae
The distances to individual wind-driven bubbles such as Planetary Nebulae (PNe) can be determined using expansion parallaxes: the angular expansion velocity in the sky is compared to the radial velocity of gas measured spectroscopically. Since the one is a pattern velocity, and the other a matter velocity, these are not necessarily the same. Using the jump conditions for both shocks and ionizat...
متن کاملPlanetary Nebulae
Planetary nebulae (PNe) can be used to trace intermediate and old stellar populations in galaxies and the intracluster medium out to approximately 20 Mpc. PNe can be easily identified with narrow-band surveys, and their chemical abundances and radial velocities can be measured with multi-slit or multi-fiber spectrographs. We briefly review what has been accomplished to date, and include tables ...
متن کاملLetter to the Editor A comparison of Hipparcos parallaxes with planetary nebulae spectroscopic distances
The Hipparcos satellite has measured the parallax of a small sample of planetary nebulae. In this paper we consider the results for 3 planetary nebulae (PN) for which spectroscopic distances have also been determined from stellar gravities. These gravities in turn have been derived fromprofile fitting of selected hydrogen and helium lines (Mendez et al., 1988 a, b, 1992). A comparison of these ...
متن کاملInterpretation of the expansion law of planetary nebulae
We reproduce the expansion velocity–radius (Vexp–Rn) relation in planetary nebulae by considering a simple dynamical model, in order to investigate the dynamical evolution and formation of planetary nebulae. In our model, the planetary nebula is formed and evolving by interaction of a fast wind from the central star with a slow wind from its progenitor, the AGB star. In particular, taking accou...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2018
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201731788