Related papers: Diffuse X-ray Emission from Planetary Nebulae with…
In this contribution, I will briefly review the development of the theory of photoionized gaseous nebulae, highlighting some of the key events. I will then present some recent developments of deep spectroscopy of planetary nebulae (PNe) and…
We identify different dust features in our compilation of infrared spectra for 267 planetary nebulae (PNe) from the Spitzer, ISO, and IRAS telescopes. We classify 209 objects according to their dust type: mixed dust (MD), oxygen-rich dust…
We utilize deep Chandra X-ray Observatory imaging and spectra of M82, the prototype of a starbursting galaxy with a multiphase wind, to map the hot plasma properties along the minor axis of the galaxy. We extract spectra from 11 regions up…
We present Suzaku spectra of X-ray emission in the fields just off the LMC X-3 sight line. OVII, OVIII, and NeIX emission lines are clearly detected, suggesting the presence of an optically thin thermal plasma with an average temperature of…
CONTEXT: Until now, only one planetary nebula (PN) has been known in the Fornax dwarf spheroidal galaxy. AIMS: The discovery of a second PN candidate, associated with one of the 5 globular clusters in the Fornax dwarf, is reported. METHODS:…
Most stars form as members of large associations within dense, very cold (10-100 K) molecular clouds. The nearby giant molecular cloud in Orion hosts several thousand stars of ages less than a few million years, many of which are located in…
Radio continuum observations trace thermal emission of ionized plasma in planetary nebulae and bring useful information on nebular geometries. A model of homogeneous sphere or shell cannot fit the nebular spectra and brightness…
Planetary nebulae (PNe) are expected to have a ~10$^{5}$ K interface layer between the $\geq$10$^{6}$ K inner hot bubble and the ~10$^{4}$ K optical nebular shell. The PN structure and evolution, and the X-ray emission depend critically on…
In this study, we present the results of photoionization modeling for 124 planetary nebulae (PNe) in the Galactic bulge. Utilizing the {\scshape cloudy} code, we derived the effective temperatures (T$_{eff}$) of the central stars, with a…
The spatial structure of the emission lines and continuum over the 50 arcsecond extent of the nearby, O-rich, planetary nebula NGC 7009 (Saturn Nebula) have been observed with the MUSE integral field spectrograph on the ESO Very Large…
The nebular evolution is followed from the vicinity of the asymptotic-giant branch across the Hertzsprung-Russell diagram until the white-dwarf domain is reached, using various central-star models coupled to different initial envelope…
We present observations of O VI 1032 emission around the helium white dwarf KPD 0005+5106 obtained with the Far Ultraviolet Spectroscopic Explorer. Previously published data, reprocessed with an updated version of the calibration pipeline,…
We have searched the entire ROSAT archive for useful observations to study X-ray emission from Galactic planetary nebulae (PNs). The search yields a sample of 63 PNs, which we call the ROSAT PN sample. About 20-25% of this sample show X-ray…
The presence of luminous hot X-ray coronae in the dark matter halos of massive spiral galaxies is a basic prediction of galaxy formation models. However, observational evidence for such coronae is very scarce, with the first few examples…
Starburst galaxies are generally associated with extended X-ray and radio halos, giving a clear hint of an outflow of gas and relativistic particles from the disk into the halo. The driving agents are, not surprisingly, active star forming…
The radiation field of central stars of planetary nebulae (CSPNe) is crucial for determining the physical conditions of planetary nebulae (PNe). Many studies in the literature model PNe using the blackbody approximation (bb) or…
The goal of the present study is twofold. First, we employ new HST/STIS spectra and photoionization modeling techniques to determine the progenitor masses of eight planetary nebulae (IC 2165, IC 3568, NGC 2440, NGC 3242, NGC 5315, NGC 5882,…
Close binary systems undergoing mass transfer or common envelope interactions can account for the morphological properties of some planetary nebulae. The search for close binary companions in planetary nebulae is hindered by the difficulty…
We present an X-ray study of the massive edge-on Sa galaxy, Sombrero (M~104; NGC 4594), based on XMM-Newton and Chandra observations. A list of 62 XMM-Newton and 175 Chandra discrete X-ray sources is provided. At energies above 2 keV, the…
We present spectrophotometry of 12 Galactic and 3 Magellanic Cloud planetary nebulae (PNe). Nine of the Galactic PNe were observed by scanning the slit across the PN. We use the fluxes of collisionally excited lines (CELs) to derive…