Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Formation of planetary debris discs around white dwarfs I: Tidal
  disruption of an extremely eccentric asteroid   25%-50% of all white dwarfs (WDs) host observable and dynamically active
remnant planetary systems based on the presence of close-in circumstellar dust
and gas and photospheric metal pollution. Currently-accepted theoretical
explanations for the origin of this matter include asteroids that survive the
star's giant branch evolution at au-scale distances and are subsequently
perturbed onto WD-grazing orbits following stellar mass loss. In this work we
investigate the tidal disruption of these highly-eccentric (e > 0.98) asteroids
as they approach and tidally disrupt around the WD. We analytically compute the
disruption timescale and compare the result with fully self-consistent
numerical simulations of rubble piles by using the N-body code PKDGRAV. We find
that this timescale is highly dependent on the orbit's pericentre and largely
independent of its semimajor axis. We establish that spherical asteroids
readily break up and form highly eccentric collisionless rings, which do not
accrete onto the WD without additional forces such as radiation or sublimation.
This finding highlights the critical importance of such forces in the physics
of WD planetary systems.

16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th