Related papers: The 3-D ionization structure of the planetary nebu…

We present the first interferometric imaging of molecular line emission from the Ring Nebula, NGC~6720, in the form of Submillimeter Array (SMA) observations of CO $J=2\rightarrow 1$ emission. The SMA $^{12}$CO(2--1) mapping data, with…

Using the Planetary Camera on board the Hubble Space Telescope we have measured the projected separation of the binary components in the nucleus of the planetary nebula Abell 35 to be larger than 0.08 arcsecs but less than 0.14 arcsecs. The…

We present the results of a 25-year program to monitor the radio flux evolution of the planetary nebula NGC7027. We find significant evolution of the spectral flux densities. The flux density at 1465 MHz, where the nebula is optically…

NGC 2438 is a classical multiple shell or halo planetary nebula (PN). Its central star and the main nebula are well studied. Also it was target of various hydrodynamic simulations (Corradi et al. 2000). This initiated a discussion whether…

We have carried out a comprehensive multiwavelength study of Bright-Rimmed Globule TC2 in the Trifid Nebula using the IRAM~30m telescope, the VLA centimeter array and the Infrared Space Observatory (ISO). TC2 is one of the very few globules…

We present new narrow-band Ha, [N II], and [O III] high-resolution images of the quadrupolar planetary nebula (PN) NGC 6309 that show in great detail its bipolar lobes and reveal new morphological features. New high- and low-dispersion…

We describe high spectral resolution, high dynamic range integral field spectroscopy of IC418 covering the spectral range 3300-8950{\AA} and compare with earlier data. We determine line fluxes, derive chemical abundances, provide a spectrum…

Searching for variability, we have observed a sample of hot post-AGB stars and young Planetary Nebulae candidates with the Very Large Array at 4.8, 8.4, and 22.4 GHz. The sources had been previously detected in the radio continuum, which is…

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…

NGC 7129 is a bright reflection nebula located in the molecular cloud complex near l=105.4, b=+9.9, about 1.15 kpc distant. Embedded within the reflection nebula is a young cluster dominated by a compact grouping of four early-type stars:…

We develop an approximate analytical solution for the transfer of line-averaged radiation in the hydrogen recombination lines for the ionized cavity and molecular shell of a spherically symmetric planetary nebula. The scattering problem is…

We apply an axially symmetric pseudo-3D photoionization model, pyCloudy, to derive the structures of 6 bipolar nebulae and 2 suggested post-bipolars in a quest to constrain the bipolar planetary nebulae evolution. HST images and VLT/UVES…

We model particle growth in a turbulent, viscously evolving protoplanetary nebula, incorporating sticking, bouncing, fragmentation, and mass transfer at high speeds. We treat small particles using a moments method and large particles using…

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…

NGC 6302 is a spectacular bipolar planetary nebula (PN) whose spectrum exhibits fast outflows and highly ionized emission lines, indicating the presence of a very hot central star (~220,000 K). Its infrared spectrum reveals a mixed oxygen…

We have constructed photo-ionization models of five galactic bulge planetary nebulae using our automatic method which enables a fully self-consistent determination of the physical parameters of a planetary nebula. The models are constrained…

We report results from a Hubble Space Telescope (HST) and Near-Infrared Camera and Multiobject Spectrometer (NICMOS) program to study the distribution of hot neutral (molecular hydrogen) and ionized circumstellar material in the young…

We analyze the stellar and nebular energy distributions of starbursts using our evolutionary synthesis model PEGASE coupled to the photoionization code CLOUDY. The originality of this study is to relate the evolution and the metallicity of…

NGC 1360 is a large planetary nebula (PN) without an obvious shell morphology. We have analyzed H-alpha images and high-dispersion echelle spectra of NGC 1360 in order to construct spatio-kinematic models and to determine its density…

As part of the CALIFA survey, we conducted a thorough 2D analysis of the ionized gas in two E/S0 galaxies, NGC6762 and NGC5966, aiming to shed light on the nature of their warm ionized ISM. We present optical IFS obtained with the PMAS/PPAK…