I=2 pion scattering length from two-pion wave functions

CP-PACS Collaboration

Aoki S

Fukugita M

Ishikawa Kenichi

Ishizuka N

Iwasaki Y

Kanaya K

Kaneko T

Kuramashi Y

Okawa Masanori

Ukawa A

Yamazaki T

Yoshié T

Physical Review D

We calculate the two-pion wave function in the ground state of the I=2 S-wave system and find the interaction range between two pions, which allows us to examine the validity of the necessary condition for the finite-volume method for the scattering length proposed by Lüscher. We work in the quenched approximation employing a renormalization group improved gauge action for gluons and an improved Wilson action for quarks at 1/a=1.207(12) GeV on 163×80, 203×80, and 243×80 lattices. We conclude that the necessary condition is satisfied within the statistical errors for the lattice sizes L>=24 (3.92 fm) when the quark mass is in the range that corresponds to mpi2=0.273–0.736 GeV2. We obtain the scattering length with a smaller statistical error from the wave function than from the two-pion time correlator.

物理学 [ 420 ]

英語

The American Physical Society

Copyright (c) 2005 The American Physical Society

[ISSN] 1550-7998

[DOI] http://dx.doi.org/10.1103/PhysRevD.71.094504 ～の異版である