Abstract
We demonstrate the effectiveness of averaging over the Wilson parameter r (which has been proposed earlier) in removing the cutoff effects of naive Wilson fermions in both the anomaly term and the pseudoscalar density term in the flavor singlet axial Ward Takahashi identity at \( \mathcal{O}\left( {{g^2}} \right) \) involving slowly varying background gauge fields. We show that it is the physical fermion contribution which is largely influenced by the r averaging. We have studied the possible interplay between finite size and cutoff effects by investigating in detail naive, \( \mathcal{O}(a) \) improved and OStm Wilson fermion cases for a range of volumes and lattice fermion mass (am). For naive Wilson fermions r averaging is shown to remove the effects of the interplay. We have shown that for the pseudoscalar density term to \( \mathcal{O}\left( {{g^2}} \right) \) the lattice result differs from the continuum result by exhibiting considerable am dependence which appears to be a manifestation of cutoff effects with naive Wilson fermion. The pseudoscalar density term to \( \mathcal{O}\left( {{g^2}} \right) \) is shown to be almost independent of am when r-averaging is performed.
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A.K. De, A. Harindranath and S. Mondal, Chiral anomaly in lattice QCD with twisted mass Wilson fermion, Phys. Lett. B 682 (2009) 150 [arXiv:0910.5611] [SPIRES].
K. Osterwalder and E. Seiler, Gauge field theories on the lattice, Annals Phys. 110 (1978) 440 [SPIRES].
K.G. Wilson, Quarks and strings on a lattice, in New phenomena in subnuclear physics, Proceedings of the International School of Subnuclear Physics, Erice Italy, Jul 11–Aug 1 1975, A. Zichichi ed., Plenum Press, New York U.S.A. (1977) [SPIRES].
H.W. Hamber and C.M. Wu, Some predictions for an improved fermion action on the lattice, Phys. Lett. B 133 (1983) 351 [SPIRES].
H.W. Hamber and C.M. Wu, The axial vector current anomaly and the meson decay constants for the improved lattice fermion action, Phys. Lett. B 136 (1984) 255 [SPIRES].
W. Wetzel, Extending improvement to fermions, Phys. Lett. B 136 (1984) 407 [SPIRES].
T. Eguchi and N. Kawamoto, Improved lattice action for Wilson fermion, Nucl. Phys. B 237 (1984) 609 [SPIRES].
L.H. Karsten and J. Smit, Lattice fermions: species doubling, chiral invariance and the triangle anomaly, Nucl. Phys. B 183 (1981) 103 [SPIRES].
W. Kerler, Axial vector anomaly in lattice gauge theory, Phys. Rev. D 23 (1981) 2384 [SPIRES].
W. Kerler, Chiral fermions on the lattice and index relations, Int. J. Mod. Phys. A 16 (2001) 3117 [hep-lat/0007023] [SPIRES].
E. Seiler and I.O. Stamatescu, Lattice fermions and theta vacua, Phys. Rev. D 25 (1982) 2177 [Erratum ibid. D 26 (1982) 534] [SPIRES].
S. Aoki, New phase structure for lattice QCD with Wilson fermions, Phys. Rev. D 30 (1984) 2653 [SPIRES].
F. David and H.W. Hamber, Chiral condensate with Wilson fermions, Nucl. Phys. B 248 (1984) 381 [SPIRES].
R. Frezzotti and G.C. Rossi, Chirally improving Wilson fermions. I: O(a) improvement, JHEP 08 (2004) 007 [hep-lat/0306014] [SPIRES].
R. Frezzotti, Wilson fermions with chirally twisted mass, Nucl. Phys. Proc. Suppl. 119 (2003) 140 [hep-lat/0210007] [SPIRES].
S. Sint, Lattice QCD with a chiral twist, hep-lat/0702008 [SPIRES].
A. Shindler, Twisted mass lattice QCD, Phys. Rept. 461 (2008) 37 [arXiv:0707.4093] [SPIRES].
ETM collaboration, R. Baron et al., Light meson physics from maximally twisted mass lattice QCD, JHEP 08 (2010) 097 [arXiv:0911.5061] [SPIRES].
P. Dimopoulos, R. Frezzotti, C. Michael, G.C. Rossi and C. Urbach, O(a 2) cutoff effects in lattice Wilson fermion simulations, Phys. Rev. D 81 (2010) 034509 [arXiv:0908.0451] [SPIRES].
H.J. Rothe and N. Sadooghi, A new look at the axial anomaly in lattice QED with Wilson fermions, Phys. Rev. D 58 (1998) 074502 [hep-lat/9803026] [SPIRES].
T. Reisz, Renormalization of Feynman integrals on the lattice, Commun. Math. Phys. 117 (1988) 79 [SPIRES].
T. Reisz, A convergence theorem for lattice Feynman integrals with massless propagators, Commun. Math. Phys. 116 (1988) 573 [SPIRES].
S. Capitani, S. Dürr and C. Hölbling, Rationale for UV-filtered clover fermions, JHEP 11 (2006) 028 [hep-lat/0607006] [SPIRES].
S. Dürr et al., Scaling study of dynamical smeared-link clover fermions, Phys. Rev. D 79 (2009) 014501 [arXiv:0802.2706] [SPIRES].
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ArXiv ePrint: 1105.0762
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De, A.K., Harindranath, A. & Mondal, S. Effect of r averaging on chiral anomaly in lattice QCD with Wilson fermion: finite volume and cutoff effects. J. High Energ. Phys. 2011, 117 (2011). https://doi.org/10.1007/JHEP07(2011)117
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DOI: https://doi.org/10.1007/JHEP07(2011)117