Zobrazeno 1 - 10
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pro vyhledávání: '"Lanz, Stefan"'
Autor:
Lanz, Stefan
The decay $\eta \to 3 \pi$ proceeds exclusively through isospin violating operators and is therefore an excellent probe to examine the strength of isospin breaking in the strong interaction. The latter can be expressed through the quark mass ratio $Q
Externí odkaz:
http://arxiv.org/abs/1809.10110
The dispersive analysis of the decay $\eta\to3\pi$ is reviewed and thoroughly updated with the aim of determining the quark mass ratio ~$Q^2=(m_s^2-m_{ud}^2)/(m_d^2-m_u^2)$. With the number of subtractions we are using, the effects generated by the f
Externí odkaz:
http://arxiv.org/abs/1807.11937
Publikováno v:
Phys. Rev. Lett. 118, 022001 (2017)
The $\eta \to 3 \pi$ amplitude is sensitive to the quark mass difference $m_u-m_d$ and offers a unique way to determine the quark mass ratio $Q^2 \equiv (m_s^2-m_{ud}^2)/(m_d^2-m_u^2)$ from experiment. We calculate the amplitude dispersively and fit
Externí odkaz:
http://arxiv.org/abs/1610.03494
Publikováno v:
Nucl.Phys.B873:137-164,2013
We extend earlier work on leading logarithms in the massive nonlinear O(n) sigma model to the case of SU(N)xSU(N)/SU(N) which coincides with mesonic chiral perturbation theory for N flavours of light quarks. We discuss the leading logarithms for the
Externí odkaz:
http://arxiv.org/abs/1303.3125
Autor:
Lanz, Stefan
Publikováno v:
PoS CD12:007,2013
In recent years, the decay eta --> 3 pi has received considerable attention from experimental and theoretical side. It is of particular theoretical interest because it allows for the determination of (m_u - m_d). In addition, for many years now theor
Externí odkaz:
http://arxiv.org/abs/1301.7282
Publikováno v:
Nucl.Phys.B860:245-266,2012
We add the Wess-Zumino-Witten term to the N=3 massive nonlinear sigma model and study the leading logarithms in the anomalous sector. We obtain the leading logarithms to six loops for \pi^0 --> \gamma^*\gamma^* and to five loops for \gamma^*\pi\pi\pi
Externí odkaz:
http://arxiv.org/abs/1201.2608
Publikováno v:
Phys.Rev.D82:034506,2010
We apply the resummed version of the L\"uscher formula to analyze finite volume corrections to the mass of the nucleon and of heavy mesons. We show that by applying the subthreshold expansion of the scattering amplitudes one can express the finite vo
Externí odkaz:
http://arxiv.org/abs/1005.1485
Publikováno v:
PoS CD09:047,2009
We present a new dispersive analysis of the isospin breaking decay eta --> 3 pi. The resulting representation of the decay amplitude allows us to determine the quark mass double ratio Q and we find as a preliminary result Q = 22.3 +/- 0.4. Finally, w
Externí odkaz:
http://arxiv.org/abs/0910.0765
Publikováno v:
In European Neuropsychopharmacology 2012 22(2):81-91
Publikováno v:
In Journal of Pain 2011 12(10):1095-1101