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Related papers: Clumping in the winds of O-type CSPNs

200 papers

I point to an interesting similarity in the morphology and some non-dimensional quantities between pairs of X-ray-deficient bubbles in clusters of galaxies and pairs of optical-deficient bubbles in planetary nebulae (PNs). This similarity…

Astrophysics · Physics 2009-11-10 Noam Soker

We review the various techniques through which wind properties of massive stars - O stars, AB supergiants, Luminous Blue Variables (LBVs), Wolf-Rayet (WR) stars and cool supergiants - are derived. The wind momentum-luminosity relation (e.g.…

Astrophysics · Physics 2015-05-20 Paul A. Crowther

Our knowledge of the presence and the strength of magnetic fields in massive O and B-type stars remains very poor. Recent observations indicate that the presence of magnetic fields is responsible for a wide range of phenomena observed in…

Solar and Stellar Astrophysics · Physics 2013-09-24 S. Hubrig , M. Schoeller , I. Ilyin , G. Lo Curto

We study the formation of photospheric emission lines in O stars and show that the rectangular profiles, sometimes double peaked, that are observed for some stars are a direct consequence of rotation, and it is unnecessary to invoke an…

Solar and Stellar Astrophysics · Physics 2015-06-05 D. John Hillier , Jean-Claude Bouret , Thierry Lanz , Joseph R. Busche

We present new results from our spectral analyses of very hot central stars achieved since the last IAU Symposium on planetary nebulae held in Canberra 2001. The analyses are mainly based on UV and far-UV spectroscopy performed with the…

Astrophysics · Physics 2009-11-13 K. Werner , A. I. D. Hoffmann , D. Jahn , T. Rauch , E. Reiff , I. Traulsen , J. W. Kruk , S. Dreizler

Many observed massive star-forming z\approx2 galaxies are large disks that exhibit irregular morphologies, with \sim1kpc, \sim10^(8-10)Msun clumps. We present the largest sample to date of high-resolution cosmological SPH simulations that…

In this paper we review the observational data for OB stars in the SMC concentrating on those aspects of their spectra which provide information on processes which may strongly influence their evolution, namely mass-loss, rotational mixing…

Astrophysics · Physics 2007-05-23 D. J. Lennon , C. J. Evans , C. Trundle

We propose that a significant fraction of the ultracompact HII regions found in massive star-forming clouds are the result of the interaction of the wind and ionizing radiation from a young massive star with the clumpy molecular cloud gas…

Astrophysics · Physics 2015-06-24 J. E. Dyson , R. J. R. Williams , M. P. Redman

Analyzing the spectra from Wolf-Rayet stars requires adequate non-LTE modeling of their expanding atmosphere. The numerical schemes for solving the radiative transfer in the co-moving frame of reference have been developed by Mihalas and…

Solar and Stellar Astrophysics · Physics 2014-11-20 W. -R. Hamann , G. Graefener , L. M. Oskinova , A. Feldmeier

The mass-loss rates of hot, massive, luminous stars are considered a decisive parameter in shaping the evolutionary tracks of such stars and influencing the interstellar medium on galactic scales. The small-scale structures (clumps)…

Astrophysics · Physics 2011-02-11 S. V. Marchenko , C. Foellmi , A. F. J. Moffat , F. Martins , J. -C. Bouret , E. Depagne

Observations at UV and optical wavelengths have revealed that galaxies at z~1-4 host star-forming regions, dubbed "clumps", which are believed to form due to the fragmentation of gravitationally unstable, gas-rich disks. However, the…

We characterize the morphological properties of a statistically relevant sample of H$\alpha$ and UV young star-forming clumps and optical complexes, observed with the \textit{Hubble Space Telescope} in six galaxies of the GASP sample…

Astrophysics of Galaxies · Physics 2023-10-12 Giunchi , E , Poggianti , B. M. , Gullieuszik , M. , Moretti , A. , Werle , A. , Zanella , A. , Vulcani , B. , Tonnesen , S. , Calzetti , D. , Bellhouse , C. , Scarlata , C. , Bacchini , C

We review the effects of clumping on the profiles of resonance doublets. By allowing the ratio of the doublet oscillator strenghts to be a free parameter, we demonstrate that doublet profiles contain more information than is normally…

Astrophysics · Physics 2007-08-08 D. Massa , R. K. Prinja , A. W. Fullerton

Nearly all types of massive stars with radiatively driven stellar winds are X-ray sources that can be observed by the presently operating powerful X-ray telescopes. In this review I briefly address recent advances in our understanding of…

Solar and Stellar Astrophysics · Physics 2016-07-27 Lidia Oskinova

A number of O stars are suspected to have (weak) magnetic fields because of the observed cyclical variability in their UV wind-lines. However, direct detections of these magnetic fields with optical spectropolarimetry have proven to be very…

The high luminosity of massive, early-type stars drives strong stellar winds through line scattering of the stars continuum radiation. Their momenta contribute substantially to the dynamics and energetics of the ambient interstellar medium…

Solar and Stellar Astrophysics · Physics 2024-06-24 Bharti Arora , Michael De Becker , Jeewan C. Pandey

Star-forming clumps have been found to significantly influence the star formation of gas-rich $z>1$ galaxies. Using public data from JWST/NIRCam (COSMOS-Web) and ALMA (FMOS-COSMOS), we study a sample of 32 massive ($>10^{10.5}\,\rm…

We seek to establish evidence in UV P Cygni line profiles that the signs of wind clumping and porosity vary with velocity. We aim to demonstrate empirically that while at most wind velocities optically thick clumps cover only a fraction of…

Solar and Stellar Astrophysics · Physics 2015-06-17 Raman Prinja , Derck Massa

We review the properties of carbon-sequence ([WC]) Wolf-Rayet central stars of planetary nebulae (CSPNe). Differences between the subtype distribution of [WC] stars and their massive WC cousins are discussed. We conclude that [WO]-type…

Astrophysics · Physics 2007-11-01 Paul A Crowther

The true mass-loss rates from massive stars are important for many branches of astrophysics. For the correct modeling of the resonance lines, which are among the key diagnostics of stellar mass-loss, the stellar wind clumping turned out to…

Solar and Stellar Astrophysics · Physics 2015-06-04 Brankica Šurlan , Wolf-Rainer Hamann , Jiří Kubát , Lidia M. Oskinova , Achim Feldmeier