Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The TIGA technique for detecting gravitational waves with a spherical
  antenna   We report the results of a theoretical and experimental study of a spherical
gravitational wave antenna. We show that it is possible to understand the data
from a spherical antenna with 6 radial resonant transducers attached to the
surface in the truncated icosahedral arrangement. We find that the errors
associated with small deviations from the ideal case are small compared to
other sources of error, such as a finite signal-to-noise ratio. An in situ
measurement technique is developed along with a general algorithm that
describes a procedure for determining the direction of an external force acting
on the antenna, including the force from a gravitational wave, using a
combination of the transducer responses. The practicality of these techniques
was verified on a room-temperature prototype antenna.

2
The categories of this paper are: math
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci