However, fast-wind Bondi-Hoyle accretion affects not only the orbital separation of the binary, but may also enhance the system eccentricity for a mass ratio <0.78 ( Dosopoulou & Kalogera 2016a, b). For hot stars, whose stellar winds are nearly spherically symmetric and fast, of ~1000 km s -1, Bondi-Hoyle accretion ( Bondi 1952) of these stellar winds onto the CO is far less effective as a MT mechanism to power an XRB than RLO. Stellar winds, on the other hand, play a less dominant role in shrinking the orbit and are relevant mostly for XRBs with massive donors that are able to generate winds sufficiently powerful to cause a high mass loss, such as those observed in Wolf-Rayet stars or red giants (e.g. RLO triggers MT through the first Lagrangian point directly into the potential well of the CO. Roche-lobe overflow (RLO) is initiated either when the donor star expands as a result of the restructuring of its stellar interior, for instance, when the star leaves the main sequence (MS) and expands outside its Roche lobe, or because angular momentum loss processes (e.g., gravitational wave radiation and magnetic braking) shrink the orbit.
In consequence of the mass transfer (MT), the orbital period of the system changes. A fraction of the lost mass is transferred to the CO that upon accretion emits X-rays, hence their name. The companion star, also known as the donor star, loses mass either because it is overflowing its Roche lobe or through stellar winds. X-ray binaries (XRBs) are evolved stellar binary systems containing a compact object (CO), a neutron star (NS) or a black hole (BH), and a companion star that is losing mass.
#BINARY SEQUENCES WHICH ARE EVENTUALLY ZERO FULL#
The full Table 2 is only available at the CDS via anonymous ftp to ( 130.79.128.5) or via At the onset of the Roche-lobe overflow, the orbit is circular and has a period of P RLO = 0.8−1.4 days. Following the SN, the system has a BH M BH,postSN = 6.4−8.2 M ⊙ and is set on an eccentric orbit. We find that a symmetric SN explosion with no or small natal kicks (a few tens of km s -1) imparted on the BH cannot be formally excluded, but large natal kicks in excess of ≳120 km s -1 increase the estimated formation rate by an order of magnitude. The orbital period decreased to 0.6−1.7 days and is still eccentric 0 ≤ e preSN ≤ 0.44. Immediately before the SN, the primary had a mass of M 1,preSN = 11.1−18.0 M ⊙, but the secondary star was largely unaffected. We find at 5% and 95% confidence, respectively, that LMC X-3 began as a ZAMS system with the mass of the primary star in the range M 1,ZAMS = 22–31 M ⊙ and a secondary star of M 2,ZAMS = 5.0−8.3 M ⊙, in a wide ( P ZAMS ≳ 2.000 days) and eccentric ( e ZAMS ≳ 0.18) orbit. We incorporated as model constraints the most up-to-date observational information throughout, which include the binary orbital properties, the companion star mass, effective temperature, surface gravity and radius, and the BH mass and spin. This allowed us to estimate potential natal kicks and the evolution of the BH spin. We used a hybrid approach that combined detailed calculations of the stellar structure and binary evolution with approximate population synthesis models. We estimated the properties of the system at four evolutionary stages: (1) at the zero-age main-sequence (ZAMS) (2) immediately before the supernova (SN) explosion of the primary (3) immediately after the SN and (4) at the moment when Roche-lobe overflow began. We have endeavoured to understand the formation and evolution of the black hole (BH) X-ray binary LMC X-3. Steiner 2, Vallia Antoniou 3, Georges Meynet 1 and Fani Dosopoulou 4ġ Observatoire de Genève, University of Geneva, Route de Sauverny, 1290 Versoix, SwitzerlandĮ-mail: MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139, USAģ Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USAĤ Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astrophysics, Northwestern University, Evanston, IL 60208, USAĪims. Mads Sørensen 1, Tassos Fragos 1, James F.
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