Related papers: Study of Bubble Nebula using IUE high resolution S…
We analyse the remnants of CK Vul (Nova Vul 1670) using optical imaging and spectroscopy. The imaging, obtained between 1991 and 2010, spans 5.6% of the life-time of the nebula. The flux of the nebula decreased during the last 2 decades.…
Investigating the bubbles generated by the interaction between asymptotic giant branch stellar outflows and the interstellar medium (ISM) is pivotal for elucidating the mechanism by which evolved low- to intermediate-mass stars enrich the…
[Abridged] We present Far Ultraviolet Spectroscopic Explorer (FUSE) observations of the young, compact planetary nebula (PN) SwSt 1 along the line of sight to its central star HD 167362. We detect circumstellar absorption lines from several…
We present observations which probe the small-scale structure of the interstellar medium using diffuse interstellar bands (DIBs). Towards HD 168075/6 in the Eagle Nebula, significant differences in DIB absorption are found between the two…
In this paper we describe the results of the first optical kinematic study of the planetary nebula BD+30 3639. This system has a central star of the Wolf-Rayet type and is believed to be fairly young. Emission line spectra were obtained at…
New observations of the Magellanic Cloud Luminous Blue Variable candidate S119 (HD269687) show the relationship of the star to its environs. Echelle spectroscopy and high-resolution HST imagery reveal an expanding bubble centered on the…
We have carried out a multi-wavelength study of the infrared dust bubble N6 to extensively investigate the molecular environs and star-forming activities therein. Mapping observations in 12CO J=1-0 and 13CO J=1-0 performed with the Purple…
The internal velocity fields of planetary nebulae are studied with a resolution of 5 km s$^{-1}$. We analyze deep echelle spectra from three nebulae in the Bulge, the Sagittarius Dwarf and the SMC. No effects of metallicity is seen, except…
The low-density region of the interstellar medium (ISM) where the Sun is located is known as the Local Bubble, a cavity filled with high-temperature and low-density plasma that may be created by a series of supernova (SN) explosions over…
Thousands of ring-like bubbles appear on infrared images of the Galaxy plane. Most of these infrared bubbles form during expansion of HII regions around massive stars. However, the physical effects that determine their morphology are still…
Recent observations have revealed a superbubble associated with the young stellar cluster OCl 352 near the W4 H II region: a void in H I emission (Normandeau, Taylor, and Dewdney), and a bright shell in H alpha emission (Dennison, Topasna,…
Based on the molecular emission in the $^{12}$CO(2-1) and $^{13}$CO(2-1) lines, and the continuum emission in the MIR and FIR towards the S21 IR dust bubble, we analyze the physical characteristics of the gas and dust linked to the nebula…
Emission lines in ionized nebulae can provide strong and useful constraints on the properties of both ionizing and non-ionizing stellar populations in regions with star formation, provided that stellar evolution and stellar atmosphere…
Spectroscopic studies indicate that gas in the photospheres of young O stars moves at speeds up to the sound speed. We show, using two-dimensional radiation MHD calculations and results from a local linear analysis, that the motions may be…
We present a new model atmosphere analysis of nine central stars of planetary nebulae. This study is based on a new generation of realistic stellar model atmospheres for hot stars; state-of-the-art, hydrodynamically consistent, spherically…
The link between the shaping of bipolar planetary nebulae and their central stars is still poorly understood. The kinematics and shaping of the multipolar nebula M 1-75 are hereby investigated, and the location and nature of its central…
Most stars will experience episodes of substantial mass loss at some point in their lives. For very massive stars, mass loss dominates their evolution, although the mass loss rates are not known exactly, particularly once the star has left…
An isolated massive star can blow a bubble, while a group of massive stars can blow superbubbles. In this paper, we examine three intriguing questions regarding bubbles and superbubbles: (1) why don't we see interstellar bubbles around…
Here we present a possible solution to the apparent discrepancy between the observed properties of LMC bubbles and the standard, constant density bubble model. A two-dimensional model of a wind-driven bubble expanding from a flattened giant…
We present an analysis of XMM-Newton observations of the superbubble 30 Dor C and compare the results with the predictions from the standard wind-blown bubble model. We find that the observed X-ray spectra cannot be fitted satisfactorily…