{"paper":{"title":"The Stellar Merger Scenario for Black Holes in the Pair-instability Gap","arxiv_id":"2010.00705","primary_cat":"astro-ph.SR","submitted_at":"2020-10-01T22:04:22+00:00","version_compiled":"v2"},"notice":"Every quoted sentence is the authors' text from the arXiv listing abstract. Labels and probabilities are the outputs of classifier-1.13.0 on the question bank abstract-p1-20260923, exactly as returned. 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envelope.","hedge":{"p":0.55,"label":"asserted"},"own_p":0.05,"main_claim_p":0.04,"quantitative":false,"quantitative_p":0.07,"role_probabilities":{"gap":0.0,"method":0.0,"result":0.0,"background":0.99,"limitation":0.0,"future_work":0.0,"contribution":0.01,"interpretation":0.0}},{"i":2,"p":0.84,"id":"s2","own":true,"role":"method","text":"We explore this scenario with detailed stellar evolution calculations, starting with ad-hoc initial conditions enforcing no core growth during the merger.","hedge":{"p":0.96,"label":"asserted"},"own_p":0.91,"main_claim_p":0.03,"quantitative":false,"quantitative_p":0.05,"role_probabilities":{"gap":0.0,"method":0.84,"result":0.0,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.16,"interpretation":0.0}},{"i":3,"p":0.46,"id":"s3","own":true,"role":"contribution","text":"We outline the main challenges this scenario has to overcome, in particular the requirement to retain enough of its mass at merger time, in the subsequent evolution, and at core-collapse.","hedge":{"p":0.96,"label":"asserted"},"own_p":0.64,"main_claim_p":0.05,"quantitative":false,"quantitative_p":0.06,"role_probabilities":{"gap":0.07,"method":0.03,"result":0.0,"background":0.12,"limitation":0.3,"future_work":0.01,"contribution":0.46,"interpretation":0.01}},{"i":4,"p":0.98,"id":"s4","own":true,"role":"result","text":"We found that these massive merger products are likely helium-rich, and spend most of their remaining lifetime within regions of the Herzsprung-Russell diagram where envelope instabilities akin to luminous blue variable (LBV) eruptions are expected.","hedge":{"p":0.9,"label":"hedged_possibility"},"own_p":0.91,"main_claim_p":0.12,"quantitative":false,"quantitative_p":0.09,"role_probabilities":{"gap":0.0,"method":0.0,"result":0.98,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.0,"interpretation":0.02}},{"i":5,"p":0.83,"id":"s5","own":true,"role":"result","text":"An energetic estimate of the amount of mass loss neglecting the back-reaction of the star suggests that the total amount of mass that can be removed at low metallicity is . 1 M .","hedge":{"p":0.86,"label":"asserted"},"own_p":0.82,"main_claim_p":0.07,"quantitative":true,"quantitative_p":0.97,"role_probabilities":{"gap":0.0,"method":0.07,"result":0.83,"background":0.0,"limitation":0.06,"future_work":0.0,"contribution":0.04,"interpretation":0.0}},{"i":6,"p":0.52,"id":"s6","own":true,"role":"interpretation","text":"This is small enough that at core-collapse our models are retaining sufficient mass to form black holes in the pair-instability gap similar to the recent ones detected by LIGO/Virgo.","hedge":{"p":0.94,"label":"asserted"},"own_p":0.86,"main_claim_p":0.61,"quantitative":true,"quantitative_p":0.51,"role_probabilities":{"gap":0.0,"method":0.0,"result":0.48,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.0,"interpretation":0.52}},{"i":7,"p":0.64,"id":"s7","own":false,"role":"limitation","text":"However, mass loss at the 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