Search Results - "Gräfener, G."

Light-travel-time diagnostics in early supernova spectra: substantial mass-loss of the IIb progenitor of SN 2013cu through a superwind by Gräfener, G., Vink, J. S.

“…The progenitors of Type-IIb supernovae (SNe IIb) are believed to have lost their H-rich envelopes almost completely in the direct pre-SN phase. Recently the…”
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An excess of massive stars in the local 30 Doradus starburst by Schneider, F R N, Sana, H, Evans, C J, Bestenlehner, J M, Castro, N, Fossati, L, Gräfener, G, Langer, N, Ramírez-Agudelo, O H, Sabín-Sanjulián, C, Simón-Díaz, S, Tramper, F, Crowther, P A, de Koter, A, de Mink, S E, Dufton, P L, Garcia, M, Gieles, M, Hénault-Brunet, V, Herrero, A, Izzard, R G, Kalari, V, Lennon, D J, Maíz Apellániz, J, Markova, N, Najarro, F, Podsiadlowski, Ph, Puls, J, Taylor, W D, van Loon, J Th, Vink, J S, Norman, C

“…The 30 Doradus star-forming region in the Large Magellanic Cloud is a nearby analog of large star-formation events in the distant universe. We determined the…”
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The delay of shock breakout due to circumstellar material evident in most type II supernovae by Förster, F., Moriya, T. J., Maureira, J. C., Anderson, J. P., Blinnikov, S., Bufano, F., Cabrera-Vives, G., Clocchiatti, A., de Jaeger, T., Estévez, P. A., Galbany, L., González-Gaitán, S., Gräfener, G., Hamuy, M., Hsiao, E. Y., Huentelemu, P., Huijse, P., Kuncarayakti, H., Martínez, J., Medina, G., Olivares E., F., Pignata, G., Razza, A., Reyes, I., San Martín, J., Smith, R. C., Vera, E., Vivas, A. K., de Ugarte Postigo, A., Yoon, S.-C., Ashall, C., Fraser, M., Gal-Yam, A., Kankare, E., Le Guillou, L., Mazzali, P. A., Walton, N. A., Young, D. R.

“…Type II supernovae (SNe II) originate from the explosion of hydrogen-rich supergiant massive stars. Their first electromagnetic signature is the shock breakout…”
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The spectral variability and magnetic field characteristics of the Of?p star HD 148937 by Wade, G. A., Grunhut, J., Gräfener, G., Howarth, I. D., Martins, F., Petit, V., Vink, J. S., Bagnulo, S., Folsom, C. P., Nazé, Y., Walborn, N. R., Townsend, R. H. D., Evans, C. J.

“…We report magnetic and spectroscopic observations and modelling of the Of?p star HD 148937 within the context of the Magnetism in Massive Stars (MiMeS) Large…”
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Author Correction: The delay of shock breakout due to circumstellar material evident in most type II supernovae by Förster, F., Moriya, T. J., Maureira, J. C., Anderson, J. P., Blinnikov, S., Bufano, F., Cabrera-Vives, G., Clocchiatti, A., de Jaeger, T., Estévez, P. A., Galbany, L., González-Gaitán, S., Gräfener, G., Hamuy, M., Hsiao, E. Y., Huentelemu, P., Huijse, P., Kuncarayakti, H., Martínez, J., Medina, G., Olivares E., F., Pignata, G., Razza, A., Reyes, I., Martín, J. San, Smith, R. C., Vera, E., Vivas, A. K., de Ugarte Postigo, A., Yoon, S.-C., Ashall, C., Fraser, M., Gal-Yam, A., Kankare, E., Le Guillou, L., Mazzali, P. A., Walton, N. A., Young, D. R.

“…In the version of this Article originally published, the authors Pablo Huijse and Pablo Huentelemu were mistakenly affiliated with the University of…”
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An absence of binary companions to Wolf-Rayet stars in the Small Magellanic Cloud: implications for mass loss and black hole masses at low metallicity by Schootemeijer, A, Shenar, T, Langer, N, Grin, N, Sana, H, Schürmann, G. Gräfener C, Wang, C, Xu, X. -T

“…A&A 689, A157 (2024) In order to predict the black hole mass distributions at high redshift, we need to understand whether very massive single stars ($M>40$…”
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The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of He ii λ1640 in young star clusters by Crowther, Paul A., Caballero-Nieves, S. M., Bostroem, K. A., Apellániz, J. Maíz, Schneider, F. R. N., Walborn, N. R., Angus, C. R., Brott, I., Bonanos, A., de Koter, A., de Mink, S. E., Evans, C. J., Gräfener, G., Herrero, A., Howarth, I. D., Langer, N., Lennon, D. J., Puls, J., Sana, H., Vink, J. S.

“…We introduce a Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) stellar census of R136a, the central ionizing star cluster of 30…”
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WR 72: a born-again planetary nebula with hydrogen-poor knots by Gvaramadze, V V, Kniazev, A Y, Gräfener, G, Langer, N

“…ABSTRACT We report the discovery of a handful of optical hydrogen-poor (H-poor) knots in the central part of an extended infrared nebula centred on the [WO1]…”
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DISCOVERY OF THE MASSIVE OVERCONTACT BINARY VFTS 352: EVIDENCE FOR ENHANCED INTERNAL MIXING by Almeida, L. A., Sana, H., Mink, S. E. de, Tramper, F., Soszyn´ski, I., Langer, N., Barbá, R. H., Cantiello, M., Damineli, A., Koter, A. de, Garcia, M., Gräfener, G., Herrero, A., Howarth, I., Apellániz, J. Maíz, Norman, C., Ramírez-Agudelo, O. H., Vink, J. S.

“…ABSTRACT The contact phase expected to precede the coalescence of two massive stars is poorly characterized due to the paucity of observational constraints…”
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The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of He?ii ?1640 in young star clusters by Crowther, Paul A, Caballero-Nieves, S M, Bostroem, K A, Apellaniz, J Maiz, Schneider, F RN, Walborn, N R, Angus, C R, Brott, I, Bonanos, A, de Koter, A, deMink, S E, Evans, C J, Graefener, G, Herrero, A, Howarth, I D, Langer, N, Lennon, D J, Puls, J, Sana, H, Vink, J S

“…We introduce a Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) stellar census of R136a, the central ionizing star cluster of 30…”
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The spectral variability and magnetic field characteristics of the Of?p star HD 148937: The variability and magnetic field of HD 148937 by Wade, G. A., Grunhut, J., Gräfener, G., Howarth, I. D., Martins, F., Petit, V., Vink, J. S., Bagnulo, S., Folsom, C. P., Nazé, Y., Walborn, N. R., Townsend, R. H. D., Evans, C. J.

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Reverse Algols and hydrogen-rich Wolf-Rayet stars from very massive binaries by Sen, K, Langer, N, Pauli, D, Gräfener, G, Schootemeijer, A, Sana, H, Shenar, T, Mahy, L, Wang, C

“…A&A 672, A198 (2023) Massive star feedback affects the evolution of galaxies, where the most massive stars may have the largest impact. The majority of massive…”
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Binarity at LOw Metallicity (BLOeM): a spectroscopic VLT monitoring survey of massive stars in the SMC by Shenar, T, Bodensteiner, J, Sana, H, Crowther, P. A, Lennon, D. J, Abdul-Masih, M, Almeida, L. A, Backs, F, Berlanas, S. R, Bernini-Peron, M, Bestenlehner, J. M, Bowman, D. M, Bronner, V. A, Britavskiy, N, de Koter, A, de Mink, S. E, Deshmukh, K, Evans, C. J, Fabry, M, Gieles, M, Gilkis, A, González-Torà, G, Gräfener, G, Götberg, Y, Hawcroft, C, Hénault-Brunet, V, Herrero, A, Holgado, G, Janssens, S, Johnston, C, Josiek, J, Justham, S, Kalari, V. M, Katabi, Z. Z, Keszthelyi, Z, Klencki, J, Kubát, J, Kubátová, B, Langer, N, Lefever, R. R, Ludwig, B, Mackey, J, Mahy, L, Apellániz, J. Maíz, Mandel, I, Maravelias, G, Marchant, P, Menon, A, Najarro, F, Oskinova, L. M, Ovadia, A. J. G. O'Grady R, Patrick, L. R, Pauli, D, Pawlak, M, Ramachandran, V, Renzo, M, Rocha, D. F, Sander, A. A. C, Sayada, T, Schneider, F. R. N, Schootemeijer, A, Schösser, E. C, Schürmann, C, Sen, K, Shahaf, S, Simón-Díaz, S, Stoop, M, van Loon, J. Th, Toonen, S, Tramper, F, Valli, R, van Son, L. A. C, Vigna-Gómez, A, Villaseñor, J. I, Vink, J. S, Wang, C, Willcox, R

“…A&A 690, A289 (2024) Surveys in the Milky Way and Large Magellanic Cloud revealed that the majority of massive stars will interact with companions during their…”
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On the optically-thick winds of Wolf-Rayet stars by Gräfener, G, Owocki, S. P, Grassitelli, L, Langer, N

“…A&A 608, A34 (2017) (abridged) The strong winds of Wolf-Rayet (WR) stars are important for the mechanical and chemical feedback of the most massive stars and…”
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Light-travel-time diagnostics in early Supernova spectra: substantial mass loss of the IIb progenitor of SN 2013cu through a superwind by Gräfener, G, Vink, J. S

“…The progenitors of type-IIb supernovae (SNe) are believed to have lost their H-rich envelopes almost completely in the direct pre-SN phase. Recently the first…”
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Narrow He II emission in star-forming galaxies at low metallicity. Stellar wind emission from a population of Very Massive Stars by Gräfener, G, Vink, J. S

“…A&A 578, L2 (2015) In a recent study star-forming galaxies with HeII emission between redshifts 2 and 4.6 have been found to occur in two modes, distinguished…”
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A massive white-dwarf merger product before final collapse by Gvaramadze, V. V, Gräfener, G, Langer, N, Maryeva, O. V, Kniazev, A. Y, Moskvitin, A. S, Spiridonova, O. I

“…Nature 569, 684-687 (30 May 2019) Gravitational wave emission can lead to the coalescence of close pairs of compact objects orbiting each other. For the case…”
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The Galactic WN stars revisited. Impact of Gaia distances on fundamental stellar parameters by Hamann, W. -R, Gräfener, G, Liermann, A, Hainich, R, Sander, A. A. C, Shenar, T, Ramachandran, V, Todt, H, Oskinova, L. M

“…A&A 625, A57 (2019) Comprehensive spectral analyses of the Galactic Wolf-Rayet stars of the nitrogen sequence (i.e.\ the WN subclass) have been performed in a…”
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VLT/X-shooter spectroscopy of massive young stellar objects in the 30 Doradus region of the Large Magellanic Cloud by van Gelder, M. L, Kaper, L, Japelj, J, Ramírez-Tannus, M. C, Ellerbroek, L. E, Barbá, R. H, Bestenlehner, J. M, Bik, A, Gräfener, G, de Koter, A, de Mink, S. E, Sabbi, E, Sana, H, Sewiło, M, Vink, J. S, Walborn, N. R

“…A&A 636, A54 (2020) The process of massive star ($M\geq8~M_\odot$) formation is still poorly understood. Observations of massive young stellar objects (MYSOs)…”
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Stellar mass-loss near the Eddington limit. Tracing the sub-photospheric layers of classical Wolf-Rayet stars by Gräfener, G, Vink, J. S

“…Towards the end of their evolution hot massive stars develop strong stellar winds and appear as emission line stars, such as WR stars or LBVs. The quantitative…”
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