000006546 001__ 6546
000006546 005__ 20240109101949.0
000006546 0247_ $$2DOI$$a10.1051/0004-6361/202245650
000006546 037__ $$aSCART-2024-0003
000006546 100__ $$aVink, Jorick S.
000006546 245__ $$aX-Shooting ULLYSES: Massive stars at low metallicity. I. Project description 
000006546 260__ $$c2023
000006546 520__ $$aObservations of individual massive stars, super-luminous supernovae, gamma-ray bursts, and gravitational wave events involving spectacular black hole mergers indicate that the low-metallicity Universe is fundamentally different from our own Galaxy. Many transient phenomena will remain enigmatic until we achieve a firm understanding of the physics and evolution of massive stars at low metallicity (Z). The Hubble Space Telescope has devoted 500 orbits to observing ∼250 massive stars at low Z in the ultraviolet (UV) with the COS and STIS spectrographs under the ULLYSES programme. The complementary X-Shooting ULLYSES (XShootU) project provides an enhanced legacy value with high-quality optical and near-infrared spectra obtained with the wide-wavelength coverage X-shooter spectrograph at ESO's Very Large Telescope. We present an overview of the XShootU project, showing that combining ULLYSES UV and XShootU optical spectra is critical for the uniform determination of stellar parameters such as effective temperature, surface gravity, luminosity, and abundances, as well as wind properties such as mass-loss rates as a function of Z. As uncertainties in stellar and wind parameters percolate into many adjacent areas of astrophysics, the data and modelling of the XShootU project is expected to be a game changer for our physical understanding of massive stars at low Z. To be able to confidently interpret James Webb Space Telescope spectra of the first stellar generations, the individual spectra of low-Z stars need to be understood, which is exactly where XShootU can deliver. 
000006546 594__ $$aNO
000006546 6531_ $$astars: atmospheres
000006546 6531_ $$astars: early-type
000006546 6531_ $$astars: winds
000006546 6531_ $$aoutflows
000006546 6531_ $$astars: evolution
000006546 6531_ $$amethods: observational
000006546 6531_ $$agalaxies: dwarf
000006546 6531_ $$aAstrophysics - Solar and Stellar Astrophysics
000006546 6531_ $$aAstrophysics - Cosmology and Nongalactic Astrophysics
000006546 6531_ $$aAstrophysics - Astrophysics of Galaxies
000006546 6531_ $$aAstrophysics - High Energy Astrophysical Phenomena
000006546 700__ $$aMehner, A.
000006546 700__ $$aCrowther, P. A.
000006546 700__ $$aFullerton, A.
000006546 700__ $$aGarcia, M.
000006546 700__ $$aMartins, F.
000006546 700__ $$aMorrell, N.
000006546 700__ $$aOskinova, L. M.
000006546 700__ $$aSt-Louis, N.
000006546 700__ $$aud-Doula, A.
000006546 700__ $$aSander, A. A. C.
000006546 700__ $$aSana, H.
000006546 700__ $$aBouret, J. -C.
000006546 700__ $$aKubátová, B.
000006546 700__ $$aMarchant, P.
000006546 700__ $$aMartins, L. P.
000006546 700__ $$aWofford, A.
000006546 700__ $$avan Loon, J. Th.
000006546 700__ $$aGrace Telford, O.
000006546 700__ $$aGötberg, Y.
000006546 700__ $$aBowman, D. M.
000006546 700__ $$aErba, C.
000006546 700__ $$aKalari, V. M.
000006546 700__ $$aAbdul-Masih, M.
000006546 700__ $$aAlkousa, T.
000006546 700__ $$aBacks, F.
000006546 700__ $$aBarbosa, C. L.
000006546 700__ $$aBerlanas, S. R.
000006546 700__ $$aBernini-Peron, M.
000006546 700__ $$aBestenlehner, J. M.
000006546 700__ $$aBlomme, R.
000006546 700__ $$aBodensteiner, J.
000006546 700__ $$aBrands, S. A.
000006546 700__ $$aEvans, C. J.
000006546 700__ $$aDavid-Uraz, A.
000006546 700__ $$aDriessen, F. A.
000006546 700__ $$aDsilva, K.
000006546 700__ $$aGeen, S.
000006546 700__ $$aGómez-González, V. M. A.
000006546 700__ $$aGrassitelli, L.
000006546 700__ $$aHamann, W. -R.
000006546 700__ $$aHawcroft, C.
000006546 700__ $$aHerrero, A.
000006546 700__ $$aHiggins, E. R.
000006546 700__ $$aJohn Hillier, D.
000006546 700__ $$aIgnace, R.
000006546 700__ $$aIstrate, A. G.
000006546 700__ $$aKaper, L.
000006546 700__ $$aKee, N. D.
000006546 700__ $$aKehrig, C.
000006546 700__ $$aKeszthelyi, Z.
000006546 700__ $$aKlencki, J.
000006546 700__ $$ade Koter, A.
000006546 700__ $$aKuiper, R.
000006546 700__ $$aLaplace, E.
000006546 700__ $$aLarkin, C. J. K.
000006546 700__ $$aLefever, R. R.
000006546 700__ $$aLeitherer, C.
000006546 700__ $$aLennon, D. J.
000006546 700__ $$aMahy, L.
000006546 700__ $$aMaíz Apellániz, J.
000006546 700__ $$aMaravelias, G.
000006546 700__ $$aMarcolino, W.
000006546 700__ $$aMcLeod, A. F.
000006546 700__ $$ade Mink, S. E.
000006546 700__ $$aNajarro, F.
000006546 700__ $$aOey, M. S.
000006546 700__ $$aParsons, T. N.
000006546 700__ $$aPauli, D.
000006546 700__ $$aPedersen, M. G.
000006546 700__ $$aPrinja, R. K.
000006546 700__ $$aRamachandran, V.
000006546 700__ $$aRamírez-Tannus, M. C.
000006546 700__ $$aSabhahit, G. N.
000006546 700__ $$aSchootemeijer, A.
000006546 700__ $$aReyero Serantes, S.
000006546 700__ $$aShenar, T.
000006546 700__ $$aStringfellow, G. S.
000006546 700__ $$aSudnik, N.
000006546 700__ $$aTramper, F.
000006546 700__ $$aWang, L.
000006546 773__ $$cA154 (28pp)$$pAstronomy & Astrophysics$$v675$$y2023
000006546 8560_ $$fronny.blomme@ksb-orb.be
000006546 85642 $$ahttps://arxiv.org/abs/2305.06376
000006546 905__ $$apublished in
000006546 980__ $$aREFERD