{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"e643e064857a1a8c05a1fdc040f5642e04afbdef4cdaf6d7d8d6f0c14336be88","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["0a441ddb7c577e4fc1f88e4430a679e022128b3c40397b159fb3156aed7c2749","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"7f62878dad429b52b49616e0cbdae7b928688a29aa4c8b487214ae79e9ab80f0","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"astro.compact-binary-origins.common-envelope","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"Many merging pairs are thought to have shrunk when one star swelled and engulfed its companion, which spiraled in and blew off the shared envelope; whether the envelope can actually be thrown off and leave a tight enough orbit has not been shown.","posed_since":"1976","precise":"In common-envelope evolution the orbital energy released during inspiral must unbind the donor envelope, conventionally parametrized by $\\alpha_{\\mathrm{CE}}\\times\\lambda$. Determine from $3D$ hydrodynamics (with recombination energy, jets and post-plunge evolution) whether envelopes of $15\\ \\text{to}\\ 40\\ M_{\\mathrm{sun}}$ red supergiant donors are fully ejected, and whether final separations of a few $R_{\\mathrm{sun}}$, small enough to merge by gravitational waves within $1.4 \\times 10^{10}\\ \\mathrm{yr}$, result. Answer: final separation and ejected mass versus donor mass and radius, and the implied share of mergers from this route versus stable mass transfer.","problem_ref":"0a441ddb7c577e4fc1f88e4430a679e022128b3c40397b159fb3156aed7c2749","references":"","settled_by":"3D simulations followed to full envelope ejection or merger for massive donors, calibrated on observed post-common-envelope binaries.","status_note":"","title":"Can common-envelope ejection produce tight merging black-hole binaries?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"4d5b2c2572a2af0098fcc76192a38acbb656aef170d425b535919f8b81e6ef58","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"61067322944b599688ffffb8236d9ea2413661ab954f279cf4af14400aed7d26","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"ddh0OnVLIRbDvStzFUiw_b4qkaJfejLuoiOJK35IaHHiZIC8yT5K7AVHeBYOQCXDAgcLobSDwOLOR1CCtBtaBA"},"schema":"pubphys.envelope/1"},"record_hash":"4d5b2c2572a2af0098fcc76192a38acbb656aef170d425b535919f8b81e6ef58","leaf_index":2314}