Related papers: Angular Expansion of Nova Shells
Narrow-band H$\alpha$ and [N {\sc ii}] images and high-dispersion spatially-resolved echelle spectroscopy of the planetary nebula NGC 6891 are presented. These observations show a great wealth of structures. The bright central nebula is…
The shock interaction and evolution of nova ejecta with a wind from a red giant star in a symbiotic binary system are investigated via three-dimensional hydrodynamics simulations. We specifically model the March 2010 outburst of the…
A detailed understanding of the physics of star and planet formation requires study of individual objects as well as statistical assessment of global properties and evolutionary trends. Observational investigations of circumstellar material…
We present proper motion measurements of oxygen-rich ejecta of the LMC supernova remnant N132D using two epochs of Hubble Space Telescope Advanced Camera for Surveys data spanning 16 years. The proper motions of 120 individual knots of…
The age of a supernova remnant (SNR) is, though undoubtedly one of the most important properties for study of its evolution, difficult to estimate reliably in most cases. In this study, we compare the dynamical and plasma ages of the SNRs…
We present a second epoch of {\it Chandra} observations of the Type Ia LMC SNR 0509-68.7 (N103B) obtained in 2017. When combined with the earlier observations from 1999, we have a 17.4-year baseline with which we can search for evidence of…
Early expansion plays a fundamental role in the dynamical evolution of young star clusters. However, until very recently most of our understanding of cluster expansion was based only on indirect evidence or on statistically limited samples…
Massive stars live fast and die young. They shine furiously for a few million years, during which time they synthesize most of the heavy elements in the universe in their cores. They end by blowing themselves up in a powerful explosion…
Supernovae release an enormous amount of energy into the interstellar medium. Their remnants can observationally be traced up to several ten-thousand years. So far more than 230 Galactic supernova remnants (SNRs) have been identified in the…
The outer shells of young supernova remnants (SNRs) are the most plausible acceleration sites of high-energy electrons with the diffusive shock acceleration (DSA) mechanism. We studied spatial and spectral properties close to the shock…
A large sample of young stellar groups is analysed aiming to investigate their clustering properties and dynamical evolution. A comparison of the Q statistical parameter, measured for the clusters, with the fractal dimension estimated for…
Connections between novae with shells and historical observations are crucial for astrophysical understanding of long-term evolution of shells and cataclysmic variables. Three of five previously considered links are revisited here: extended…
We show that the expansion of ejecta in Tycho's supernova remnant (SNR) is consistent with a spherically symmetric shell, based on Suzaku measurements of the Doppler broadened X-ray emission lines. All the strong K_alpha line emission show…
A fraction of classical novae form dust during the early stages of their outbursts. The classical CO nova V5668 Sgr (Nova Sgr. 2015b) underwent a deep photometric minimum about 100 days after outburst that was covered across the spectrum. A…
The evolution of the luminosity of nova shells in the century following the nova outburst is studied for the lines H-alpha, H-beta, and [O III]. About 1200 flux measurements from 96 objects have been collected from the literature, from…
Context: Open clusters' dynamical evolution is driven by stellar evolution, internal dynamics and external forces, which according to dynamical simulations, will evaporate them in a timescale of about 1 Ga. However, about 10\% of the known…
We present investigations of the interaction between the relativistic, precessing jets of the microquasar SS433 with the surrounding, expanding Supernova Remnant (SNR) shell W50, and the consequent evolution in the inhomogeneous…
Context. Most stars form in clusters or associations but only a small number of these groups are expected to remain bound for longer than a few Myr. Once star formation has ended and the molecular gas around young stellar objects has been…
We report the results of our follow-up campaign of the peculiar supernova ASASSN-15no, based on optical data covering ~300 days of its evolution. Initially the spectra show a pure blackbody continuum. After few days, the HeI 5876 A…
Hydrodynamical interaction of spherical ejecta freely expanding at mildly relativistic speeds into an ambient cold medium is studied in semi-analytical and numerical ways to investigate how ejecta produced in energetic stellar explosions…