@misc{10498/35543,
year = {2024},
url = {http://hdl.handle.net/10498/35543},
abstract = {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.},
publisher = {EDP Sciences},
keywords = {Galaxies: luminosity function, mass function},
keywords = {Galaxies: starburst;},
keywords = {Galaxy: abundances;},
keywords = {Stars: massive;},
keywords = {Stars: Population II;},
keywords = {Stars: Population III},
title = {Contribution of very massive stars to the sulfur abundance in star-forming galaxies: Role of pair-instability supernovae},
doi = {10.1051/0004-6361/202348231},
author = {Goswami, Sabyasachi and Vilchez, J.M. and Pérez-Díaz, B. and Silva, L. and Bressan, A. and Pérez-Montero, E.},
}