Leptonic decay constants fK, fD and fDs with Nf = 2+1+1 twisted-mass lattice QCD

التفاصيل البيبلوغرافية
العنوان: Leptonic decay constants fK, fD and fDs with Nf = 2+1+1 twisted-mass lattice QCD
المؤلفون: Carrasco, N., Dimopoulos, P., Frezzotti, R., Lami, P., Lubicz, V., Nazzaro, F., Picca, E., Riggio, L., Rossi, G. C., Sanfilippo, F., Simula, S., Tarantino, C.
المصدر: Phys. Rev. D 91, 054507 (2015)
سنة النشر: 2014
المجموعة: High Energy Physics - Lattice
High Energy Physics - Phenomenology
مصطلحات موضوعية: High Energy Physics - Lattice, High Energy Physics - Phenomenology
الوصف: We present a lattice QCD calculation of the pseudoscalar decay constants fK, fD and fDs performed using the gauge configurations produced by the European Twisted Mass Collaboration with Nf = 2 + 1 + 1 dynamical quarks, which include in the sea, besides two light mass degenerate quarks, also the strange and charm quarks with masses close to their values in the real world. The simulations are based on a unitary setup for the two light mass-degenerate quarks and on a mixed action approach for the strange and charm quarks. We use data simulated at three different values of the lattice spacing in the range 0.06 - 0.09 fm and at pion masses in the range 210 - 450 MeV. Our main results are: fK+ / fpi+ = 1.184 (16), fK+ = 154.4 (2.0) MeV, which incorporate the leading strong isospin breaking correction due to the up- and down-quark mass difference, and fK = 155.0 (1.9) MeV, fD = 207.4 (3.8) MeV, fDs = 247.2 (4.1) MeV, fDs / fD = 1.192 (22) and (fDs / fD) / (fK / fpi) = 1.003 (14) obtained in the isospin symmetric limit of QCD. Combined with the experimental measurements of the leptonic decay rates of kaon, pion, D- and Ds-mesons our results lead to the following determination of the CKM matrix elements: |Vus| = 0.2269 (29), |Vcd| = 0.2221 (67) and |Vcs| = 1.014 (24). Using the latest value of |Vud| from superallowed nuclear beta decays the unitarity of the first row of the CKM matrix is fulfilled at the permille level.
Comment: 20 pp., 4 figures; revised version to appear in PRD; improved calculation of IB effects for fK+; minor changes in the final values. arXiv admin note: text overlap with arXiv:1403.4504
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevD.91.054507
URL الوصول: http://arxiv.org/abs/1411.7908
رقم الأكسشن: edsarx.1411.7908
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevD.91.054507