The structure of planetary nebulae: theory vs. practice

Sabbadin, F.; Turatto, M.; Ragazzoni, Roberto; Benetti, S.

doi:10.1051/0004-6361:20054554

Cited by 25 publications

(36 citation statements)

References 64 publications

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“…2) resembles that of the optical image of many elliptical PNs, e.g., NGC 6826 (Balick 1987;Balick et al 1998). Cygnus A hot spots, i.e., the heads of the two jets, resemble the structure of pairs of ansae − two opposite dense blobs along the major axis of some elliptical PNs − suggesting that the ansae are formed by jets (see for example the ansae of the PN NGC 7009; Balick 1987;Balick et al 1998;Sabbadin et al 2003).…”

Section: Introductionmentioning

confidence: 79%

Bubbles in planetary nebulae and clusters of galaxies: Jet properties

Soker

2004

A&A

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Abstract. I derive constraints on jet properties for inflating pairs of bubbles in planetary nebulae and clusters of galaxies. This work is motivated by the similarity in morphology and some non-dimensional quantities between X-ray-deficient bubbles in clusters of galaxies and the optical-deficient bubbles in planetary nebulae, which were pointed out in an earlier work. In the present Paper I find that for inflating fat bubbles, the opening angle of the jets must be large, i.e., the half opening angle measured from the symmetry axis of the jets should typically be α > ∼ 40• . For such wide-opening angle jets, a collimated fast wind (CFW) is a more appropriate term. Narrow jets will form elongated lobes rather than fat bubbles. I emphasize the need to include jets with large opening angle, i.e., α 30−70• , in simulating bubble inflation in both planetary nebulae and (cooling flow) clusters of galaxies.

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Section: Introductionmentioning

confidence: 79%

Bubbles in planetary nebulae and clusters of galaxies: Jet properties

Soker

2004

A&A

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“…Leaving simplistic "modern views" of PN evolution out of consideration, we remark that updated 1D radiationhydrodynamical evolutionary models (Perinotto et al 2004b;Schönberner et al 2005) still partly fail in reproducing the positive expansion velocity gradient of the main shell (the Wilson's law;Wilson 1950;Weedman 1968), and the gas distribution observed in a representative sample of carefully deprojected "true" PNe (Sabbadin et al 2006, and references therein). Such model-PN vs. true-PN discrepancies suggest that the former tend to systematically overestimate the relative importance of wind interaction (as supported by a recent revision downward of mass-loss rates in PN central stars, due to clumping of the fast stellar wind; Kudritzki et al 2006;Prinja et al 2007).…”

Section: Introductionmentioning

confidence: 98%

The gas turbulence in planetary nebulae: quantification and multi-D maps from long-slit, wide-spectral range echellograms

Sabbadin¹,

Turatto

Benetti³

et al. 2008

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Context. This methodological paper is part of a short series dedicated to the long-standing astronomical problem of de-projecting the bi-dimensional, apparent morphology of a three-dimensional distribution of gas. Aims. We focus on the quantification and spatial recovery of turbulent motions in planetary nebulae (and other classes of expanding nebulae) by means of long-slit echellograms over a wide spectral range. Methods. We introduce some basic theoretical notions, discuss the observational methodology, and develop an accurate procedure disentangling all broadening components (instrumental resolution, thermal motions, turbulence, gradient of the expansion velocity, and fine structure of hydrogen-like ions) of the velocity profile in all spatial positions of each spectral image. This allows us to extract random, non-thermal motions at unprecedented accuracy, and to map them in 1-, 2-and 3-dimensions. Results. We discuss general and specific applications of the method. We present the solution to practical problems in the multidimensional turbulence-analysis of a testing-planetary nebula (NGC 7009), using the three-step procedure (spatio-kinematics, tomography, and 3D rendering) developed at the Astronomical Observatory of Padua (Italy). In addition, we introduce an observational paradigm valid for all spectroscopic parameters in all classes of expanding nebulae. Conclusions. Unsteady, chaotic motions at a local scale constitute a fundamental (although elusive) kinematical parameter of each planetary nebula, providing deep insights on its different shaping agents and mechanisms, and on their mutual interaction. The detailed study of turbulence, its stratification within a target and (possible) systematic variation among different sub-classes of planetary nebulae deserve long-slit, multi-position angle, wide-spectral range echellograms containing emissions at low-, medium-, and highionization, to be analyzed pixel-to-pixel with a straightforward and versatile methodology, extracting all the physical information (flux, kinematics, electron temperature and density, ionic and chemical abundances, etc.) stored in each frame at best.

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“…This factor is known to be relatively small. We assume Vf-s=5 km s −1 (Sabbadin et al, 2006 (Latter et al, 2000). The hot CSPN ionizes the surrounding gases in a shell which can be seen in a (stratified) multiple sub-shell structures of forbidden lines.…”

Section: Line Profile and Shell Expansion Velocitymentioning

confidence: 99%