The impact of companions on stellar evolution

TL;DR

Recent advances highlight the significant influence of binary companions on stellar evolution, reshaping understanding of various astrophysical phenomena and prompting a comprehensive reevaluation of classical and new stellar events.

Contribution

This review synthesizes recent discoveries and perspectives on binary star interactions, emphasizing their role in phenomena previously attributed solely to single stars.

Findings

Binary interactions are crucial in explaining type Ia supernovae.

New phenomena like gravitational wave sources are linked to binary evolution.

Reassessment of classical phenomena includes binary effects in supernova classifications.

Abstract

Stellar astrophysicists are increasingly taking into account the effects of orbiting companions on stellar evolution. New discoveries, many thanks to systematic time-domain surveys, have underlined the role of binary star interactions in a range of astrophysical events, including some that were previously interpreted as due uniquely to single stellar evolution. Here, we review classical binary phenomena such as type Ia supernovae, and discuss new phenomena such as intermediate luminosity transients, gravitational wave-producing double black holes, or the interaction between stars and their planets. Finally, we examine the reassessment of well-known phenomena in light of interpretations that include both single and binary stars, for example supernovae of type Ib and Ic or luminous blue variables. At the same time we contextualise the new discoveries within the framework and nomenclature of the corpus of knowledge on binary stellar evolution. The last decade has heralded an era of revival in stellar astrophysics as the complexity of stellar observations is increasingly interpreted with an interplay of single and binary scenarios. The next decade, with the advent of massive projects such as the Large Synoptic Survey Telescope, the Square Kilometre Array, the James Webb Space Telescope and increasingly sophisticated computational methods, will see the birth of an expanded framework of stellar evolution that will have repercussions in many other areas of astrophysics such as galactic evolution and nucleosynthesis.