2018MNRAS.475L..49M

We propose that massive Thorne-Zytkow objects can explode. A Thorne-Zytkow object is a theoretically predicted star that has a neutron core. When nuclear reactions supporting a massive Thorne-Zytkow object terminate, a strong accretion occurs towards the central neutron core. The accretion rate is large enough to sustain a super-Eddington accretion towards the neutron core. The neutron core may collapse to a black hole after a while. A strong large-scale outflow or a jet can be launched from the super-Eddington accretion disc and the collapsing Thorne-Zytkow object can be turned into an explosion. The ejecta have about 10 M_☉ but the explosion energy depends on when the accretion is suppressed. We presume that the explosion energy could be as low as ∼10⁴⁷ erg and such a low-energy explosion could be observed like a failed supernova. The maximum possible explosion energy is ∼10⁵² erg and such a high-energy explosion could be observed as an energetic Type II supernova or a superluminous supernova. Explosions of Thorne-Zytkow objects may provide a new path to spread lithium and other heavy elements produced through the irp process such as molybdenum in the Universe.