Isospin breaking effects due to the up-down mass difference in lattice QCD

  • RM123 collaboration
  • G. M. de Divitiis
  • P. Dimopoulos
  • R. Frezzotti
  • V. Lubicz
  • G. Martinelli
  • R. Petronzio
  • G. C. Rossi
  • F. Sanfilippo
  • S. Simula
  • N. Tantalo
  • C. Tarantino
Article

Abstract

We present a new method to evaluate with high precision leading isospin breaking effects due to the small mass difference between the up and down quarks using lattice QCD. Our proposal is applicable in principle to any hadronic observable which can be computed on the lattice. It is based on the expansion of the path-integral in powers of the small parameter m d m u . In this paper, we apply this method to compute the leading isospin breaking effects for several physical quantities of interest: the kaon meson masses, the kaon decay constant, the form factors of semileptonic K 3 decays and the neutron-proton mass splitting.

Keywords

Lattice QCD Quark Masses and SM Parameters 

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Copyright information

© SISSA, Trieste, Italy 2012

Authors and Affiliations

  • RM123 collaboration
  • G. M. de Divitiis
    • 1
    • 2
  • P. Dimopoulos
    • 3
    • 4
  • R. Frezzotti
    • 1
    • 2
  • V. Lubicz
    • 5
    • 6
  • G. Martinelli
    • 7
    • 4
  • R. Petronzio
    • 1
    • 2
  • G. C. Rossi
    • 1
    • 2
  • F. Sanfilippo
    • 3
    • 4
  • S. Simula
    • 6
  • N. Tantalo
    • 1
    • 2
  • C. Tarantino
    • 5
    • 6
  1. 1.Dip. di FisicaUniversità di Roma “Tor Vergata”RomeItaly
  2. 2.INFN, Sez. di Roma “Tor Vergata”RomeItaly
  3. 3.Dip. di FisicaUniversità di Roma “La Sapienza”RomeItaly
  4. 4.INFN, Sezione di RomaRomeItaly
  5. 5.Dip. di FisicaUniversità Roma TreRomeItaly
  6. 6.INFN, Sez. di Roma IIIRomeItaly
  7. 7.SISSATriesteItaly

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