3 ms·

It’s totally plausible. But if the core of your star is sufficiently massive then the initial collapse takes it over the Chandrasekhar limit & it forms a black

by pja 6y ago

It’s totally plausible. But if the core of your star is sufficiently massive then the initial collapse takes it over the Chandrasekhar limit & it forms a black hole immediately. Then the rest of the stellar material just falls into it. The fine details vary depending on mass, composition & spin of the rest of the material: if the star is spinning fast enough an accretion disk might form and drive jets which is one possible method of generating a GRB.

sandworm101 6y ago
>> Then the rest of the stellar material just falls into it. Spherical chickens in a vacuum. This would be true of a non-spinning black hole. In reality they all spin. The star was spinning before collapse. So a tiny amount quietly falls in, but the bulk of the outer shell quickly accelerates, energizes, jets form and generally the massive releases of energy blasts material away.
- lmilcin 6y ago
  Having part of the star form accretion disc and then slowly radiate the energy is entirely different from the star converting significant part of its mass into energy and radiating it in couple of hours. Also jets are highly directional and you have good chance to be away from the cone. I am not a physicist but I suspect that extremely active star turning into black hole might be much less luminous than the star itself. Accretion disks can be very luminous but this is typically for very large holes in the centers of galaxies. Because we observe these huge stars only because they are so highly active, the act of converting it to much less luminous system might be undistinguishable from the star disappearing.
- pja 6y ago
  This is definitely outside my area of competence, but I believe that jets that manage to escape the stellar volume only form under a very specific set of circumstances: https://en.wikipedia.org/wiki/Gamma-ray_burst_progenitors#Collapsar_model https://en.wikipedia.org/wiki/Gamma-ray_burst_progenitors#Co... I believe current models suggest that a low-metallicity stars (which are the ones who’s core can collage straight to a black hole, with no intermediate neutron star) will typically collapse with no supernova or other visible trace. High mass (> 90 SM) might lead to a GRB, but not a supernovae. You can follow the references at https://en.wikipedia.org/wiki/Failed_supernova https://en.wikipedia.org/wiki/Failed_supernova & the supernova wikipedia page for the gory details.

by pja 6y ago

sandworm101 6y ago

>> Then the rest of the stellar material just falls into it. Spherical chickens in a vacuum. This would be true of a non-spinning black hole. In reality they all spin. The star was spinning before collapse. So a tiny amount quietly falls in, but the bulk of the outer shell quickly accelerates, energizes, jets form and generally the massive releases of energy blasts material away.

lmilcin 6y ago
Having part of the star form accretion disc and then slowly radiate the energy is entirely different from the star converting significant part of its mass into energy and radiating it in couple of hours. Also jets are highly directional and you have good chance to be away from the cone. I am not a physicist but I suspect that extremely active star turning into black hole might be much less luminous than the star itself. Accretion disks can be very luminous but this is typically for very large holes in the centers of galaxies. Because we observe these huge stars only because they are so highly active, the act of converting it to much less luminous system might be undistinguishable from the star disappearing.
pja 6y ago
This is definitely outside my area of competence, but I believe that jets that manage to escape the stellar volume only form under a very specific set of circumstances: https://en.wikipedia.org/wiki/Gamma-ray_burst_progenitors#Collapsar_model https://en.wikipedia.org/wiki/Gamma-ray_burst_progenitors#Co... I believe current models suggest that a low-metallicity stars (which are the ones who’s core can collage straight to a black hole, with no intermediate neutron star) will typically collapse with no supernova or other visible trace. High mass (> 90 SM) might lead to a GRB, but not a supernovae. You can follow the references at https://en.wikipedia.org/wiki/Failed_supernova https://en.wikipedia.org/wiki/Failed_supernova & the supernova wikipedia page for the gory details.