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+ /fπ+ = 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/fπ) = 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 β decays the unitarity of the first row of the CKM matrix is fulfilled at the permille level.

Carrasco, N., Dimopoulos, P., Frezzotti, R., Lami, P., Lubicz, V., Nazzaro, F., et al. (2015). Leptonic decay constants fK, fD, and fDs with Nf=2+1+1 twisted-mass lattice QCD. PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY, 91(5) [10.1103/physrevd.91.054507].

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

Frezzotti, R;Rossi, G;
2015-03-17

Abstract

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+ /fπ+ = 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/fπ) = 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 β decays the unitarity of the first row of the CKM matrix is fulfilled at the permille level.
17-mar-2015
Pubblicato
Rilevanza internazionale
Articolo
Esperti anonimi
Settore FIS/02 - FISICA TEORICA, MODELLI E METODI MATEMATICI
English
Carrasco, N., Dimopoulos, P., Frezzotti, R., Lami, P., Lubicz, V., Nazzaro, F., et al. (2015). Leptonic decay constants fK, fD, and fDs with Nf=2+1+1 twisted-mass lattice QCD. PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY, 91(5) [10.1103/physrevd.91.054507].
Carrasco, N; Dimopoulos, P; Frezzotti, R; Lami, P; Lubicz, V; Nazzaro, F; Picca, E; Riggio, L; Rossi, G; Sanfilippo, F; Simula, S; Tarantino, C...espandi
Articolo su rivista
File in questo prodotto:
File Dimensione Formato  
PhysRevD.91.054507.pdf

solo utenti autorizzati

Descrizione: articolo principale - file pdf
Tipologia: Versione Editoriale (PDF)
Licenza: Copyright dell'editore
Dimensione 324.2 kB
Formato Adobe PDF
324.2 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/263216
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 127
  • ???jsp.display-item.citation.isi??? 109
social impact