Rapid population synthesis of double neutron stars Alejandro - PowerPoint PPT Presentation

Rapid population synthesis of double neutron stars Alejandro Vigna-Gómez avignagomez@nbi.ku.dk Bonn 2020 14th Bonn workshop on the formation and evolution of neutron stars

1 Double Neutron Stars (DNSs): Observations Data as presented in Vigna-Gómez+2018 (arXiv:1805.07974) * GW170817: Abbott+2017 (arXiv:1710.05832) ^GW190425 : Abbott+2019 (arXiv:2001.01761) χ < 0 . 89 10 Probability density χ < 0 . 05 ^GW190425 Galactic BNS 8 *GW170817: m tot = 2.74 , 2.82 Msol 6 4 2 0 2 . 00 2 . 25 2 . 50 2 . 75 3 . 00 3 . 25 3 . 50 3 . 75 4 . 00 m tot ( M � ) See Tauris+2017 and references therein.

2 Synthetic Population Period-eccentricity (P-e) diagram Hertzsprung-Russell diagram Vigna-Gómez+2020 (arXiv:2001.09829) https://zenodo.org/record/3593844

3 • Rapid population synthesis code • Isolated binary evolution • Sampling: MC/AIS • Integration over cosmic history • Interpolation using machine learning https://compas.science/ compas-user@googlegroups.com

4 Population Synthesis Initial Distributions p(M 1 ,q,e,a) ZAMS f acc V kick Mass γ M rem Supernovae Transfer Common Winds Envelope λ f WR α f LBV p(M 1 ,q,e,a) DNS Final Distributions

5 5 Galactic-like DNS population Galactic-like DNS population Data: https://zenodo.org/record/3593844 Data: https://zenodo.org/record/3593844

6 DNS Formation (69% of all DNSs) Credit: T. Rebagliato & A. Vigna-Gómez Plots: https://zenodo.org/record/3634498

7 DNS Formation (20% of all DNSs) Credit: T. Rebagliato & A. Vigna-Gómez Plots: https://zenodo.org/record/3634498

8 Distinctive Common-envelope Episodes Neutron star – Giant donor Single-core common-envelope episode Channel I (~70%) Giant donor – Giant companion Double-core common-envelope episode Channel II (~20%)

9 Sub-Populations Vigna-Gómez+2020 (arXiv:2001.09829)

10 Synthetic Population BLUE: single-core RED: double-core Vigna-Gómez+2020 (arXiv:2001.09829) https://zenodo.org/record/3593844

11 Binary Neutron Stars: Achille’s Heel Fryer Delayed, Z=0.0142

12 Conclusions Two formation channels: DNS merger rates (Gpc^3 yr^ − 1): • Single-core • GW170817 : 110–3840 Wide • GW190425 : 250–2810 • Galactic-like • • COMPAS^: 240–280 • Double-core Merging • LISA-like (?) • LIGO-like (?) • ^“Similar” results with MOBSE, ComBiNe, StarTrack, etc.