@misc{MartinezNunezKretschmarBozzoetal.2017,
  author    = {Martinez-Nunez, Silvia and Kretschmar, Peter and Bozzo, Enrico and Oskinova, Lida and Puls, Joachim and Sidoli, Lara and Sundqvist, Jon Olof and Blay, Pere and Falanga, Maurizio and Furst, Felix and Gimenez-Garcia, Angel and Kreykenbohm, Ingo and Kuehnel, Matthias and Sander, Andreas Alexander Christoph and Torrejon, Jose Miguel and Wilms, Joern},
  title     = {Towards a Unified View of Inhomogeneous Stellar Winds in Isolated Supergiant Stars and Supergiant High Mass X-Ray Binaries},
  series = {Space science reviews},
  volume    = {212},
  journal   = {Space science reviews},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {0038-6308},
  doi       = {10.1007/s11214-017-0340-1},
  pages     = {59 -- 150},
  year      = {2017},
  abstract  = {Massive stars, at least similar to 10 times more massive than the Sun, have two key properties that make them the main drivers of evolution of star clusters, galaxies, and the Universe as a whole. On the one hand, the outer layers of massive stars are so hot that they produce most of the ionizing ultraviolet radiation of galaxies; in fact, the first massive stars helped to re-ionize the Universe after its Dark Ages. Another important property of massive stars are the strong stellar winds and outflows they produce. This mass loss, and finally the explosion of a massive star as a supernova or a gamma-ray burst, provide a significant input of mechanical and radiative energy into the interstellar space. These two properties together make massive stars one of the most important cosmic engines: they trigger the star formation and enrich the interstellar medium with heavy elements, that ultimately leads to formation of Earth-like rocky planets and the development of complex life. The study of massive star winds is thus a truly multidisciplinary field and has a wide impact on different areas of astronomy. In recent years observational and theoretical evidences have been growing that these winds are not smooth and homogeneous as previously assumed, but rather populated by dense "clumps". The presence of these structures dramatically affects the mass loss rates derived from the study of stellar winds. Clump properties in isolated stars are nowadays inferred mostly through indirect methods (i.e., spectroscopic observations of line profiles in various wavelength regimes, and their analysis based on tailored, inhomogeneous wind models). The limited characterization of the clump physical properties (mass, size) obtained so far have led to large uncertainties in the mass loss rates from massive stars. Such uncertainties limit our understanding of the role of massive star winds in galactic and cosmic evolution. Supergiant high mass X-ray binaries (SgXBs) are among the brightest X-ray sources in the sky. A large number of them consist of a neutron star accreting from the wind of a massive companion and producing a powerful X-ray source. The characteristics of the stellar wind together with the complex interactions between the compact object and the donor star determine the observed X-ray output from all these systems. Consequently, the use of SgXBs for studies of massive stars is only possible when the physics of the stellar winds, the compact objects, and accretion mechanisms are combined together and confronted with observations. This detailed review summarises the current knowledge on the theory and observations of winds from massive stars, as well as on observations and accretion processes in wind-fed high mass X-ray binaries. The aim is to combine in the near future all available theoretical diagnostics and observational measurements to achieve a unified picture of massive star winds in isolated objects and in binary systems.},
  language  = {en}
}
@misc{VinkHegerKrumholzetal.2012,
  author    = {Vink, Jorick Sandor and Heger, Alexander and Krumholz, Mark R. and Puls, Joachim and Banerjee, Shiladitya and Castro, Norberto and Chen, K.-J. and Chen{\`e}, A.-N. and Crowther, P. A. and Daminelli, A. and Gr{\"a}fener, G. and Groh, J. H. and Hamann, Wolf-Rainer and Heap, S. and Herrero, A. and Kaper, L. and Najarro, F. and Oskinova, Lida and Roman-Lopes, A. and Rosen, A. and Sander, A. and Shirazi, M. and Sugawara, Y. and Tramper, F. and Vanbeveren, D. and Voss, R. and Wofford, A. and Zhang, Y.},
  title     = {Very massive stars in the local universe},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {601},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-41522},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-415220},
  pages     = {29},
  year      = {2012},
  abstract  = {Recent studies have claimed the existence of very massive stars (VMS) up to 300 M⊙ in the local Universe. As this finding may represent a paradigm shift for the canonical stellar upper-mass limit of 150 M⊙, it is timely to discuss the status of the data, as well as the far-reaching implications of such objects. We held a Joint Discussion at the General Assembly in Beijing to discuss (i) the determination of the current masses of the most massive stars, (ii) the formation of VMS, (iii) their mass loss, and (iv) their evolution and final fate. The prime aim was to reach broad consensus between observers and theorists on how to identify and quantify the dominant physical processes.},
  language  = {en}
}
@inproceedings{Puls2007,
  author    = {Puls, Joachim},
  title     = {Discussion : X-rays},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18000},
  year      = {2007},
  abstract  = {Clumping in hot-star winds : proceedings of an international workshop held in Potsdam, Germany, 18. - 22. June 2007},
  language  = {en}
}
@inproceedings{KrtičkaPulsKubat2007,
  author    = {Krtička, Jiri and Puls, Joachim and Kub{\´a}t, Jiř{\´i}},
  title     = {The influence of clumping on predicted O star wind parameters},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17969},
  year      = {2007},
  abstract  = {We study the influence of clumping on the predicted wind structure of O-type stars. For this purpose we artificially include clumping into our stationary wind models. When the clumps are assumed to be optically thin, the radiative line force increases compared to corresponding unclumped models, with a similar effect on either the mass-loss rate or the terminal velocity (depending on the onset of clumping). Optically thick clumps, alternatively, might be able to decrease the radiative force.},
  language  = {en}
}
@inproceedings{UrbanejaKudritzkiPuls2007,
  author    = {Urbaneja, M. A. and Kudritzki, R.-P. and Puls, Joachim},
  title     = {Clumping in the winds of O-type CSPNs},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17801},
  year      = {2007},
  abstract  = {Recent studies of massive O-type stars present clear evidences of inhomogeneous and clumped winds. O-type (H-rich) central stars of planetary nebulae (CSPNs) are in some ways the low mass-low luminosity analogous of those massive stars. In this contribution, we present preliminary results of our on-going multi-wavelength (FUV, UV and optical) study of the winds of Galactic CSPNs. Particular emphasis will be given to the clumping factors derived by means of optical lines (Hα and Heii 4686) and "classic" FUV (and UV) lines.},
  language  = {en}
}
@inproceedings{NajarroPulsHerreroetal.2007,
  author    = {Najarro, F. and Puls, Joachim and Herrero, A. and Hanson, M. M. and Mart{\´i}n-Pintado, J. and Hillier, D. J.},
  title     = {Tracking the Clumping in OB Stars from UV to radio},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17701},
  year      = {2007},
  abstract  = {We review different line and continua diagnostics from the UV to radio, which can be utilized to simultaneously constrain the clumping structure throughout the stellar wind of massive OB stars.},
  language  = {en}
}
@inproceedings{PulsMarkovaNajarroetal.2007,
  author    = {Puls, Joachim and Markova, N. and Najarro, F. and Hanson, M. M.},
  title     = {Clumping in O-star winds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17683},
  year      = {2007},
  abstract  = {We review various diagnostics of clumping in O-star winds, with special emphasis on its radial stratification. Implications and problems are discussed, and promising NIR methods are presented.},
  language  = {en}
}