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ABSTRACT A large fraction of massive stars are found in higher order systems where the presence of a tertiary may significantly modify the system’s evolution. In particular, it can lead to increased numbers of compact object binaries and accelerate their mergers with important implications for gravitational wave observations. Using Gaia, we constrain the number of Galactic supernovae that produce unbound triples. We do this by searching 8 supernova remnants for stars with consistent Gaia parallaxes and paths intersecting near the centre of the supernova remnant at a time consistent with the age of the remnant. We find no candidates for unbound triple systems. Combined with prior work, less than 11.4 per cent of supernovae leave behind unbound triples at a 90 per cent confidence limit. The absence of such systems limits their role in the evolution of massive stars and the formation of merging compact objects.
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Supernovae producing unbound binaries and triples
ABSTRACT The fraction of stars that are in binaries or triples at the time of stellar death and the fraction of these systems that survive the supernova explosion are crucial constraints for evolution models and predictions for gravitational wave source populations. These fractions are also subject to direct observational determination. Here, we search 10 supernova remnants containing compact objects with proper motions for unbound binaries or triples using Gaia EDR3 and new statistical methods and tests for false positives. We confirm the one known example of an unbound binary, HD 37424 in G180.0−01.7, and find no other examples. Combining this with our previous searches for bound and unbound binaries, and assuming no bias in favour of finding interacting binaries, we find that 72.0 per cent (52.2–86.4 per cent, 90 per cent confidence) of supernova producing neutron stars are not binaries at the time of explosion, 13.9 per cent (5.4–27.2 per cent) produce bound binaries, and 12.5 per cent (2.8–31.3 per cent) produce unbound binaries. With a strong bias in favour of finding interacting binaries, the medians shift to 76.0 per cent were not binaries at death, 9.5 per cent leave bound binaries, and 13.2 per cent leave unbound binaries. Of explosions that do not leave binaries, $${\lt}18.9{{\ \rm per\ cent}}$$ can be fully unbound triples. These limits are conservatively for $$M\gt 5\, \mathrm{M}_\odot$$ companions, although the mass limits for some individual systems are significantly stronger. At birth, the progenitor of PSR J0538+2817 was probably a 13–$$19\, \mathrm{M}_\odot$$ star, and at the time of explosion, it was probably a Roche limited, partially stripped star transferring mass to HD 37424 and then producing a Type IIL or IIb supernova.
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- Award ID(s):
- 1814440
- PAR ID:
- 10348500
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 507
- Issue:
- 4
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- 5832 to 5846
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/mnras/stab2483
