Population III stars, born from the primordial gas in the Universe, lose a negligible fraction of their mass via stellar winds and possibly follow a top-heavy mass function. Hence, they have often been regarded as the ideal progenitors of massive black holes (BHs), even above the pair instability mass gap. Here, we evolve a large set of Population III binary stars (metallicity Z = 10(-11)) with our population-synthesis code SEVN, and compare them with Population II binary stars (Z = 10(-4)). In our models, the lower edge of the pair-instability mass gap corresponds to a BH mass of approximate to 86 (approximate to 91) M-circle dot for single Population III (II) stars. Overall, we find only mild differences between the properties of binary BHs (BBHs) born from Population III and II stars, especially if we adopt the same initial mass function and initial orbital properties. Most BBH mergers born from Population III and II stars have primary BH mass below the pair-instability gap, and the maximum secondary BH mass is <50 M-circle dot. Only up to approximate to 3.3 per cent (approximate to 0.09 per cent) BBH mergers from Population III (II) progenitors have primary mass above the gap. Unlike metal-rich binary stars, the main formation channel of BBH mergers from Population III and II stars involves only stable mass transfer episodes in our fiducial model.

Massive binary black holes from Population II and III stars / Costa, Guglielmo; Mapelli, Michela; Iorio, Giuliano; Santoliquido, Filippo; Escobar, Gastón J; Klessen, Ralf S; Bressan, Alessandro. - In: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY. - ISSN 0035-8711. - 525:2(2023), pp. 2891-2906. [10.1093/mnras/stad2443]

Massive binary black holes from Population II and III stars

Costa, Guglielmo;Mapelli, Michela;Bressan, Alessandro
2023-01-01

Abstract

Population III stars, born from the primordial gas in the Universe, lose a negligible fraction of their mass via stellar winds and possibly follow a top-heavy mass function. Hence, they have often been regarded as the ideal progenitors of massive black holes (BHs), even above the pair instability mass gap. Here, we evolve a large set of Population III binary stars (metallicity Z = 10(-11)) with our population-synthesis code SEVN, and compare them with Population II binary stars (Z = 10(-4)). In our models, the lower edge of the pair-instability mass gap corresponds to a BH mass of approximate to 86 (approximate to 91) M-circle dot for single Population III (II) stars. Overall, we find only mild differences between the properties of binary BHs (BBHs) born from Population III and II stars, especially if we adopt the same initial mass function and initial orbital properties. Most BBH mergers born from Population III and II stars have primary BH mass below the pair-instability gap, and the maximum secondary BH mass is <50 M-circle dot. Only up to approximate to 3.3 per cent (approximate to 0.09 per cent) BBH mergers from Population III (II) progenitors have primary mass above the gap. Unlike metal-rich binary stars, the main formation channel of BBH mergers from Population III and II stars involves only stable mass transfer episodes in our fiducial model.
2023
525
2
2891
2906
https://doi.org/10.1093/mnras/stad2443
https://arxiv.org/abs/2303.15511
Costa, Guglielmo; Mapelli, Michela; Iorio, Giuliano; Santoliquido, Filippo; Escobar, Gastón J; Klessen, Ralf S; Bressan, Alessandro
File in questo prodotto:
File Dimensione Formato  
2303.15511.pdf

accesso aperto

Tipologia: Documento in Pre-print
Licenza: Non specificato
Dimensione 1.87 MB
Formato Adobe PDF
1.87 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11767/137691
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 2
  • ???jsp.display-item.citation.isi??? 0
social impact