相关论文: Morpho-kinematic and photoionization models of the…
We present narrow-band images and long-slit echelle spectra of the planetary nebula (PN) NGC 6778. The data show this PN as bipolar, with a very prominent low-excitation equatorial toroid, high-excitation lobes and two pairs of collimated…
We use a 3D photoionization modeling tool to study the morpho-kinematic properties of the Planetary Nebula (PN) NGC 3132. We show that it is possible to reproduce the low resolution observations (spectra and images) with an ellipsoidal…
We present a 3D photoionization model of the PN NGC 6302, one of the most complex objects of its kind. Our Mocassin model is composed of an extremely dense circumstellar disk and a large pair of diffuse bipolar lobes, a combination…
Although the planetary nebula NGC 6781 appears to possess an elliptical morphology, its kinematic and emission characteristics are in many ways unusual, and it is possible that it may represent a bipolar source oriented close to the line of…
The planetary nebula NGC 6881 displays in the optical a quadrupolar morphology consisting of two pairs of highly collimated bipolar lobes aligned along different directions. An additional bipolar ejection is revealed by the hydrogen…
We present 3D hydrodynamical simulations of an isotropic fast wind interacting with a previously ejected toroidally-shaped slow wind in order to model both the observed morphology and the kinematics of the planetary nebula (PN) NGC 6302.…
NGC 6337 is a member of the rare group of planetary nebulae where a close binary nucleus has been identified. The nebula's morphology and emission line profiles are both unusual, particularly the latter. We present a thorough mapping of…
The planetary nebula (PN) NGC 6778 harbors a binary central star with a short orbital period and displays two systems of fast collimated outflows. In order to assess the influence of the evolution through a common-envelope phase of the…
We present a study of the structure and kinematics of the triple-shell planetary nebula NGC 7662 based on long-slit echelle spectroscopic observations and HST archival narrow-band images. The structure of NGC 7662 main nebula consists of a…
The iconic planetary nebula (PN) NGC 7027 is bright, nearby (D ~ 1 kpc), highly ionized, intricately structured, and well observed. This nebula is hence an ideal case study for understanding PN shaping and evolution processes. Accordingly,…
We present an extensive, long-slit, high-resolution coverage of the complex planetary nebula (PN), NGC 7026. We acquired ten spectra using the Manchester Echelle Spectrometer at San Pedro Martir Observatory in Baja California, Mexico, and…
Continuing our series of papers on the three-dimensional (3-D) structures of and accurate distances to Planetary Nebulae (PNe), we present our study of the planetary nebula NGC6781. For this object we construct a 3-D photoionization model…
With its remarkable double-S shape, IC 4634 is an archetype of point-symmetric planetary nebulae (PN). In this paper, we present a detailed study of this PN using archival HST WFPC2 and ground-based narrow-band images to investigate its…
We present high-resolution images of the strongly bipolar planetary nebula NGC 6537, obtained with Hubble Space Telescope and with the infrared adaptive optics system on the Very Large Telescope. The central star is detected for the first…
The link between the shaping of bipolar planetary nebulae and the mass ejection activity of their central stars is still poorly understood. Appropriately characterizing the evolution of the shells ejected during the late stages of evolution…
We present a new modeling tool for planetary nebulae (PNe), based on 3D photoionization calculations. From models for two theoretical PNe, we show that the enhancement in the equatorial zone observed in several PNe is not necessarily due to…
In this paper we present the results of optical high-resolution imaging and spectroscopy of the complex planetary nebula (PN) NGC~3242. Our study is based on the analysis of the narrowband H$\alpha$ $\lambda$6563\AA , [O III]…
We present narrow-band near-infrared images of a sample of 11 Galactic planetary nebulae (PNe) obtained in the molecular hydrogen (H$_{2}$) 2.122 $\mu$m and Br$\gamma$ 2.166 $\mu$m emission lines and the $K_{\rm c}$ 2.218 $\mu$m continuum.…
We performed a detailed photometric analysis and photoionisation modelling on three high excitation multiple shell planetary nebulae: NGC 3242, NGC 6826 and NGC 7662. Archival HST/WFPC2 narrow band filter images were used to investigate…
NGC 6369 is a double-shell planetary nebula (PN) consisting of a bright annular inner shell with faint bipolar extensions and a filamentary envelope. We have used ground- and space-based narrow-band optical and near-IR images, broad-band…