Chiral logs in twisted mass lattice QCD with large isospin breaking

Baer, Oliver

doi:10.1103/PHYSREVD.82.094505

Title: Chiral logs in twisted mass lattice QCD with large isospin breaking

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Abstract

The pion masses and the pion decay constant are calculated to 1-loop order in SU(2) twisted mass Wilson chiral perturbation theory, assuming a large pion mass splitting and tuning to maximal twist. Taking the large mass splitting at leading order in the chiral expansion leads to significant modifications in the chiral logarithms. For example, the result for the charged pion mass contains a chiral logarithm that involves the neutral pion mass instead of the charged one. Similar modifications appear in the results for the neutral pion mass and the decay constant. These new results are used in fits to lattice data obtained recently by the European twisted mass collaboration. The data can be fitted well, in general better than with the standard chiral perturbation theory expressions that ignore the mass splitting. The impact on the extraction of low-energy couplings is briefly discussed.

Authors:

Baer, Oliver ^[1]

Institute of Physics, Humboldt University Berlin, Newtonstrasse 15, 12489 Berlin (Germany)

Publication Date:: Mon Nov 01 00:00:00 EDT 2010

OSTI Identifier:: 21503813

Resource Type:: Journal Article

Journal Name:: Physical Review. D, Particles Fields

Additional Journal Information:: Journal Volume: 82; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.82.094505; (c) 2010 American Institute of Physics; Journal ID: ISSN 0556-2821

Country of Publication:: United States

Language:: English

Subject:: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHIRALITY; COUPLING; EXPANSION; EXTRACTION; ISOSPIN; MASS; MODIFICATIONS; PARTICLE DECAY; PERTURBATION THEORY; PIONS NEUTRAL; QUANTUM CHROMODYNAMICS; SU-2 GROUPS; BOSONS; DECAY; ELEMENTARY PARTICLES; FIELD THEORIES; HADRONS; LIE GROUPS; MESONS; PARTICLE PROPERTIES; PIONS; PSEUDOSCALAR MESONS; QUANTUM FIELD THEORY; SEPARATION PROCESSES; SU GROUPS; SYMMETRY GROUPS

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                    Baer, Oliver. Chiral logs in twisted mass lattice QCD with large isospin breaking.  United States: N. p., 2010. 
        Web.  doi:10.1103/PHYSREVD.82.094505.

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                    Baer, Oliver. Chiral logs in twisted mass lattice QCD with large isospin breaking.  United States.  https://doi.org/10.1103/PHYSREVD.82.094505

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                    Baer, Oliver. 2010.  
        "Chiral logs in twisted mass lattice QCD with large isospin breaking".  United States.  https://doi.org/10.1103/PHYSREVD.82.094505.

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@article{osti_21503813,

  title        = {Chiral logs in twisted mass lattice QCD with large isospin breaking},

  author       = {Baer, Oliver},

  abstractNote = {The pion masses and the pion decay constant are calculated to 1-loop order in SU(2) twisted mass Wilson chiral perturbation theory, assuming a large pion mass splitting and tuning to maximal twist. Taking the large mass splitting at leading order in the chiral expansion leads to significant modifications in the chiral logarithms. For example, the result for the charged pion mass contains a chiral logarithm that involves the neutral pion mass instead of the charged one. Similar modifications appear in the results for the neutral pion mass and the decay constant. These new results are used in fits to lattice data obtained recently by the European twisted mass collaboration. The data can be fitted well, in general better than with the standard chiral perturbation theory expressions that ignore the mass splitting. The impact on the extraction of low-energy couplings is briefly discussed.},

  doi          = {10.1103/PHYSREVD.82.094505},

  url          = {https://www.osti.gov/biblio/21503813},
  journal      = {Physical Review. D, Particles Fields},

  issn         = {0556-2821},

  number       = 9,

  volume       = 82,

  place        = {United States},

  year         = {Mon Nov 01 00:00:00 EDT 2010},

  month        = {Mon Nov 01 00:00:00 EDT 2010}

}

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