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تسجيل مستخدم جديدUpdate of the ALEPH non-strange spectral functions from hadronic $tau$ decays
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An update of the ALEPH non-strange spectral functions from hadronic $tau$ decays is presented. Compared to the 2005 ALEPH publication, the main improvement is related to the use of a new method to unfold the measured mass spectra from detector effects. This procedure also corrects a previous problem in the correlations between the unfolded mass bins. Results from QCD studies and for the evaluation of the hadronic vacuum polarisation contribution to the anomalous muon magnetic moment are derived using the new spectral functions. They are found in agreement with published results based on the previous set of spectral functions.
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Hadronic $tau$ decays provide a clean laboratory for the precise study of quantum chromodynamics (QCD). Observables based on the spectral functions of hadronic $tau$ decays can be related to QCD quark-level calculations to determine fundamental quant
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The vector and axial-vector ALEPH hadronic spectral functions from $tau$-decay are used to probe potential quark-hadron duality violations (DV). This is done in the framework of finite energy QCD sum rules (FESR). A pinched integration kernel is intr
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