RT journal article
T1 Contribution of very massive stars to the sulfur abundance in star-forming galaxies: Role of pair-instability supernovae
A1 Goswami, Sabyasachi
A1 Vilchez, J.M.
A1 Pérez-Díaz, B.
A1 Silva, L.
A1 Bressan, A.
A1 Pérez-Montero, E.
A2 Física Aplicada
K1 Galaxies: luminosity function, mass function
K1 Galaxies: starburst;
K1 Galaxy: abundances;
K1 Stars: massive;
K1 Stars: Population II;
K1 Stars: Population III
AB Context. Recent work presented increasing evidence of high non-constant S/O abundance ratios observed in star-forming metal-poor galaxies that deviated from the constant canonical S/O across a wide range of O/H abundances. Similar peculiarly high Fe/O ratios have also recently been detected. Aims. We investigate whether these high S/O ratios at low metallicities could be explained when the process of pair-instability supernovae (PISN) in chemical modelling is included, through which a similar behaviour of the Fe/O ratios was reproduced successfully. Methods. We used chemical evolution models that considered the stages of PISN in the previously published yields and adopted a suitable initial mass function (IMF) to characterize this evolutionary stage appropriately. Results. The peculiarly high values and the behaviour of the observed S/O versus O/H relation can be reproduced when the ejecta of very massive stars that go through the process of PISN are taken into account. Additionally, a bimodal top-heavy IMF and an initial strong burst of star formation are required to reach the reported high S/O values. Conclusions. We show that the role of very massive stars going through the process of PISN should be taken into account to explain the chemical enrichment of sulphur and oxygen in metal-poor star-forming regions. © 2024 EDP Sciences. All rights reserved.
PB EDP Sciences
SN 1432-0746
YR 2024
FD 2024
LK http://hdl.handle.net/10498/35543
UL http://hdl.handle.net/10498/35543
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 11-nov-2026