Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: L\"uscher's finite size method with twisted boundary conditions: an
  application to $J/\psi$-$\phi$ system to search for narrow resonance   We investigate an application of twisted boundary conditions for study of
low-energy hadron-hadron interactions with L\"ushcer's finite size method. It
allows us to calculate the phase shifts for elastic scattering of two hadrons
at any small value of the scattering momentum even in a finite volume. We then
can extract model independent information of low-energy scattering parameters
such as the scattering length, the effective range and the effective volume
from the $S$-wave and $P$-wave scattering phase shifts through the effective
range expansion. This approach also enables us to examine the existence of
near-threshold and narrow resonance states, of which characteristic is observed
in many of newly discovered charmonium-like $XYZ$ mesons. As a simple example,
we demonstrate our method for low-energy $J/\psi$-$\phi$ scatterings to search
for Y(4140) resonance using 2+1 flavor PACS-CS gauge configurations at the
lightest pion mass, $m_{\pi}=156$ MeV.

14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
2
The categories of this paper are: math