Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Innermost stable circular orbits of a Kerr-like Metric with Quadrupole   The innermost stable circular orbit equation of a test particle is obtained
for an approximate Kerr-like spacetime with quadrupole moment. We derived the
effective potential for the radial coordinate by the Euler-Lagrange method.
This equation can be employed to measure the mass quadrupole by observational
means, because from this equation a quadratic polynomial for the quadrupole
moment can be found. As expected, the limiting cases of this equation are found
to be the known cases of Kerr and Schwarzschild.

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The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
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The categories of this paper are: comp-gas
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The categories of this paper are: cond-mat
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
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The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph