Detailed simulations of massive hierarchical triple star systems : Exploring the impact of the stellar physics on the evolutionary pathways of massive hierarchical triple systems

Article Article scientifique Article Detailed simulations of massive hierarchical triple star systems : Exploring the impact of the stellar physics on the evolutionary pathways of massive hierarchical triple systems eng 2025-06-17 2025-06 author Sciarini Luca Théo 0009-0001-7331-2238 945187 Département d'astronomie (ASTRO) author Ekström Sylvia 0000-0002-2564-5660 514725 Département d'astronomie (ASTRO) author Kummer Floris 0000-0002-6056-3070 author Rieder Steven 972300 author Bruenech Caspar 0009-0003-9851-771X author Toonen Silvia author Farrell Eoin 402585 A240 10.1051/0004-6361/202553955 0004-6361 https://www.aanda.org/10.1051/0004-6361/202553955 Context. Recent observations estimate that approximately 30% of early B- and O-type stars are found in triple systems. To date, the evolution of triple star systems has mainly been modeled using fast stellar codes. The accuracy of these codes is expected to decrease with increasing mass, which limits their reliability for predicting the evolutionary pathways of massive hierarchical triple star systems. Aims. Our aim was to investigate the discrepancies in the predicted evolution of massive stars between fast (Hurley tracks) codes and detailed ( MESA ) codes, and to assess how these differences can impact the evolutionary pathways of massive triple star systems. Methods. We coupled the TRES code, which by default uses SEBA to MESA to perform the first simulations of triple systems that combine a triple secular evolutionary code with a detailed, on-the-fly stellar code. After examining the differences between the single star evolution predicted by the two stellar codes ( MESA and SEBA ), we simulate the evolution of a set of triple systems and compare their predicted evolutionary pathways under identical initial conditions. Results. We show that among very massive stars ( M ≥ 50 M ⊙ ), the stellar tracks predicted by the two codes become increasingly divergent with increasing mass and wind mass-loss efficiency. Notably, the maximal radial extent, which is crucial for determining whether the components of the triple systems interact, can differ by up to two orders of magnitude between the two stellar codes in the considered mass range and with a standard mass-loss efficiency. We demonstrate that this has significant implications for the predicted evolutionary pathways of triple systems and leads to divergences between the predictions of simulations performed with MESA and SEBA . In particular, we show that using MESA as the stellar code, the minimum period for avoiding inner mass transfer is reduced by three orders of magnitude compared to what is predicted by SEBA . We highlight that this result has consequences for the formation of gravitational wave sources through the triple compact object channel. Conclusions. Our simulations offer new insights into the physics of triple star systems, as some relevant processes (mass-loss by stellar winds, radial expansion, tides, precession due to the distortion of the stars) can be treated more self-consistently. They indicate that the results of triple system population synthesis studies must be interpreted cautiously, in particular when the considered masses are outside the range of the grid the fast codes are based on and when significant stellar winds are considered. Dewey 520 Nederlandse Organisatie voor Wetenschappelijk Onderzoek 203.061 European Commission STARs at the EXtreme 833925 STAREX EU H2020 Swiss National Science Foundation From stars to stellar populations 212124 CH Projects 26 Département d'astronomie 12 false 867 Groupe Meynet Astronomy & astrophysics 698 4355452d-b22e-44cd-b22d-97ea7bfa13e7 Article (Published version) Public Article_scientifique_from_crossref.pdf 5473179 application/pdf CC BY-4.0 0454cbb7eb0a1bd7fe3f13307bfbd49ec01073bff9be206a10b9abde9d5bf81a openAccess Faculté des sciences / Département d'astronomie

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Detailed simulations of massive hierarchical triple star systems : Exploring the impact of the stellar physics on the evolutionary pathways of massive hierarchical triple systems	Astronomy & astrophysics	2025	25	25
Simulating star formation in spiral galaxies	Proceedings of the International Astronomical Union	2023	71	411

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