Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The fate of fallback matter around newly born compact objects   The presence of fallback disks around young neutron stars has been invoked
over the years to explain a large variety of phenomena. Here we perform a
numerical investigation of the formation of such disks during a supernova
explosion, considering both neutron star (NS) and black hole (BH) remnants.
Using the public code MESA, we compute the angular momentum distribution of the
pre-supernova material, for stars with initial masses M in the range 13 - 40
Msun, initial surface rotational velocities vsurf between 25% and 75% of the
critical velocity, and for metallicities Z of 1%, 10% and 100% of the solar
value. These pre SN models are exploded with energies E varying between 10^{50}
- 3x10^{52} ergs, and the amount of fallback material is computed. We find
that, if magnetic torques play an important role in angular momentum transport,
then fallback disks around NSs, even for low-metallicity main sequence stars,
are not an outcome of SN explosions. Formation of such disks around young NSs
can only happen under the condition of negligible magnetic torques and a
fine-tuned explosion energy. For those stars which leave behind BH remnants,
disk formation is ubiquitous if magnetic fields do not play a strong role;
however, unlike the NS case, even with strong magnetic coupling in the
interior, a disk can form in a large region of the {Z,M,vsurf,E} parameter
space. Together with the compact, hyperaccreting fallback disks widely
discussed in the literature, we identify regions in the above parameter space
which lead to extended, long-lived disks around BHs. We find that the physical
conditions in these disks may be conducive to planet formation, hence leading
to the possible existence of planets orbiting black holes.

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The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
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The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
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The categories of this paper are: econ
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat