Phase-resolved spectroscopic analysis of the eclipsing black hole X-ray binary M33 X-7: System properties, accretion, and evolution
Autor: | V. Ramachandran, L. M. Oskinova, W.-R. Hamann, A. A. C. Sander, H. Todt, D. Pauli, T. Shenar, J. M. Torrejón, K. A. Postnov, J. M. Blondin, E. Bozzo, R. Hainich, D. Massa |
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Přispěvatelé: | Low Energy Astrophysics (API, FNWI), Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Astronomía y Astrofísica |
Jazyk: | angličtina |
Rok vydání: | 2022 |
Předmět: |
stars
MODEL ATMOSPHERES evolution [Stars] FOS: Physical sciences Astronomy & Astrophysics fundamental parameters [Stars] outflows STELLAR WINDS massive TERMINAL VELOCITIES X-rays evolution massive [Stars] PRESUPERNOVA EVOLUTION black holes [Stars] winds [Stars] Solar and Stellar Astrophysics (astro-ph.SR) High Energy Astrophysical Phenomena (astro-ph.HE) HST UV SPECTRA Science & Technology IC 10 X-1 MASS-LOSS Astronomy and Astrophysics black holes winds Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science Physical Sciences binaries [X-rays] O-STARS binaries NGC 300 X-1 Astrophysics - High Energy Astrophysical Phenomena PHOTON IMAGING CAMERA fundamental parameters |
Zdroj: | Astronomy and Astrophysics, 667:A77. EDP Sciences |
ISSN: | 0004-6361 |
Popis: | M33 X-7 is the only known eclipsing black hole high mass X-ray binary. The system is reported to contain a very massive O supergiant donor and a massive black hole in a short orbit. The high X-ray luminosity and its location in the metal-poor galaxy M33 make it a unique laboratory for studying the winds of metal-poor donor stars with black hole companions and it helps us to understand the potential progenitors of black hole mergers. Using phase-resolved simultaneous HST- and XMM-Newton-observations, we traced the interaction of the stellar wind with the black hole. Our comprehensive spectroscopic investigation of the donor star (X-ray+UV+optical) yields new stellar and wind parameters for the system that differs significantly from previous estimates. In particular, the masses of the components are considerably reduced to 38 for the O-star donor and 11.4 for the black hole. The O giant is overfilling its Roche lobe and shows surface He enrichment. The donor shows a densely clumped wind with a mass-loss rate that matches theoretical predictions. We investigated the wind-driving contributions from different ions and the changes in the ionization structure due to X-ray illumination. Toward the black hole, the wind is strongly quenched due to strong X-ray illumination. For this system, the standard wind-fed accretion scenario alone cannot explain the observed X-ray luminosity, pointing toward an additional mass overflow, which is in line with our acceleration calculations. The X-ray photoionization creates an He II emission region emitting $10^{47}$ ph/s. We computed binary evolutionary tracks for the system using MESA. Currently, the system is transitioning toward an unstable mass transfer phase, resulting in a common envelope of the black hole and donor. Since the mass ratio is q~3.3 and the period is short, the system is unlikely to survive the common envelope, but will rather merge. Accepted for publication in Astronomy & Astrophysics |
Databáze: | OpenAIRE |
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