Evaluating chemically homogeneous evolution in stellar binaries: Electromagnetic implications -- Ionizing photons, SLSN-I, GRB, Ic-BL

Abstract

We investigate the occurrence of rapid rotation induced Chemically Homogeneous Evolution (CHE) caused by strong tides and mass accretion in binary systems. Using , we derive a relation for the minimum initial angular frequency required by a single star to experience CHE. This is then extended to derive a similar relation for accretion induced CHE in binaries by generalizing the analytical relation in Packet (1981). In contrast to traditionally assumed 5-10 per cent accretion of initial mass for spinning up an accretor (resulting in CHE) with 𝑍 0.004 and 𝑀 20M , this value can drop to ∼ 2 per cent for efficient angular momentum accretion. On the other hand, for certain systems, one might overestimate the efficiency of accretion induced spin-up. We conduct a population study using by evolving stars under the influence of strong tides in short-period binaries and also account for the updated effect of accretion induced rapid rotation. We find accretion CHE (compared to tidal CHE) to be the dominant means of producing homogeneous stars even at 10 per cent angular momentum accretion efficiency during mass transfer. Unlike tidal CHE, it is seen that CH stars arising due to accretion can retain a larger fraction of their angular momentum till core-collapse. Thus we show that accretion CHE could be an important formation channel for electromagnetic transients like GRBs/Ic-BL (SLSN-I/Ic-BL) under the collapsar (magnetar) formalism and a single CH star could lead to both the transients under their respective formation scenario.

The Role of Jets in Exploding Supernovae and in Shaping their Remnants

“…The above properties distinguish the jittering jets explosion mechanism from other jet-driven explosion mechanisms (e.g., LeBlanc & Wilson 1970;Khokhlov et al 1999;Aloy et al 2000;MacFadyen et al 2001;Burrows et al 2007;Barkov & Komissarov 2008;Wheeler et al 2008;Maeda et al 2012;López-Cámara et al 2013;Bromberg & Tchekhovskoy 2016;Nishimura et al 2017;Sobacchi et al 2017;Grimmett et al 2021;Gottlieb et al 2022aGottlieb et al , 2022cGhodla et al 2022;Perley et al 2022). In particular, these mechanisms assume a rapidly rotating precollapse core, something that is not required in the jittering jets explosion mechanism.…”

Searching for ejected supernova companions in the era of precise proper motion and radial velocity measurements

“…Pols et al 1991), in extreme cases this could lead to unusual evolution (such as homogeneous or quasi-homogeneous evolution, e.g. Eldridge et al 2011;Mandel & de Mink 2016;Ghodla et al 2022), or they can be polluted by winds from a stripped-envelope companion (Clark et al 2014). It has also been suggested that secondaries might appear inflated and red for a short time (∼1000 yr) after the supernova of a companion, as a result of the impact of the primary ejecta (Liu et al 2015;Hirai et al 2018;Ogata et al 2021).…”

“…Upcoming multi-object spectrographs and integral field units such as WEAVE (WHT Enhanced Area Velocity Explorer, Dalton et al 2014) and 4MOST (4-metre Multi-Object Spectrograph Telescope, de Jong et al 2014) also offer new opportunities to characterise candidates in the vicinity of supernova remnants and young neutron stars, through the identification of stars with high radial velocities, high rotational velocities or unusual chemical abundances, which may be indicative of past binary interactions (e.g. Clark et al 2014;Ghodla et al 2022).…”