Pulsational instability of supergiant protostars: Do they grow supermassive by accretion?

Understand

Supermassive stars (SMSs; M>10^5 Msun) and their remnant black holes are promising progenitors for supermassive black holes (SMBHs) observed in the early universe at z>7.

• It has been postulated that SMSs forms through very rapid mass accretion onto a protostar at a high rate exceeding 0.01 Msun/yr.
• According to recent studies, such rapidly accreting protostars evolve into "supergiant protostars", i.e.
• protostars consisting of a bloated envelope and a contracting core, similar to giant star.