Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Head-on collision of unequal mass black holes: close-limit predictions   The close-limit method has given approximations in excellent agreement with
those of numerical relativity for collisions of equal mass black holes. We
consider here colliding holes with unequal mass, for which numerical relativity
results are not available. We try to ask two questions: (i) Can we get
approximate answers to astrophysical questions (ideal mass ratio for energy
production, maximum recoil velocity, etc.), and (ii) can we better understand
the limitations of approximation methods. There is some success in answering
the first type of question, but more with the second, especially in connection
with the issue of measures of the intrinsic mass of the colliding holes, and of
the range of validity of the method.

33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph