| Article | |
| Report number | arXiv:1308.1851 ; CERN-PH-TH-2013-173 ; IFIC-13-47 ; LPT-ORSAY-13-59 ; LTH-982 ; MITP-13-045 ; RM3-TH-13-6 ; ROM2F-2013-12 ; CERN-PH-TH-2013-173 |
| Title | B-physics from Nf=2 tmQCD: the Standard Model and beyond |
| Author(s) |
Carrasco, N. (Valencia U. ; Valencia U., IFIC) ; Ciuchini, M. (INFN, Rome3 ; Rome III U.) ; Dimopoulos, P. (Enrico Fermi Ctr., Rome ; Rome U., Tor Vergata) ; Frezzotti, R. (Rome U., Tor Vergata ; INFN, Rome2) ; Giménez, V. (Valencia U. ; Valencia U., IFIC) ; Herdoiza, G. (Mainz U., Inst. Kernphys.) ; Lubicz, V. (Rome III U. ; INFN, Rome3) ; Michael, C. (Liverpool U., Dept. Math.) ; Picca, E. (Rome III U.) ; Rossi, G.C. (Rome U., Tor Vergata ; INFN, Rome2) ; Sanfilippo, F. (Orsay, LPT) ; Shindler, A. (CERN) ; Silvestrini, L. (INFN, Rome ; Rome U.) ; Simula, S. (INFN, Rome3 ; Rome III U.) ; Tarantino, C. (Rome III U. ; INFN, Rome3) |
| Publication | 2014 |
| Imprint | 08 Aug 2013 |
| Number of pages | 52 |
| Note | Comments: 51 pages, 25 figures, 14 tables version accepted for publication in JHEP, extended discussion on error budget, lattice results unchanged, updated upper bound for C1 in Tables 5 and 6, references added; 55 pages, 25 figures, 14 tables |
| In: | JHEP 03 (2014) 016 |
| DOI | 10.1007/JHEP03(2014)016 |
| Subject category | Particle Physics - Lattice |
| Abstract | We present a lattice QCD computation of the b-quark mass, the B and B_s decay constants, the B-mixing bag parameters for the full four-fermion operator basis as well as determinations for \xi and f_{Bq}\sqrt{B_i^{(q)}} extrapolated to the continuum limit and to the physical pion mass. We used N_f = 2 twisted mass Wilson fermions at four values of the lattice spacing with pion masses ranging from 280 to 500 MeV. Extrapolation in the heavy quark mass from the charm to the bottom quark region has been carried out on ratios of physical quantities computed at nearby quark masses, exploiting the fact that they have an exactly known infinite mass limit. Our results are m_b(m_b, \overline{\rm{MS}})=4.29(12) GeV, f_{Bs}=228(8) MeV, f_{B}=189(8) MeV and f_{Bs}/f_B=1.206(24). Moreover with our results for the bag-parameters we find \xi=1.225(31), B_1^{(s)}/B_1^{(d)}=1.01(2), f_{Bd}\sqrt{\hat{B}_{1}^{(d)}} = 216(10) MeV and f_{Bs}\sqrt{\hat{B}_{1}^{(s)}} = 262(10) MeV. We also computed the bag parameters for the complete basis of the four-fermion operators which are required in beyond the SM theories. By using these results for the bag parameters we are able to provide a refined Unitarity Triangle analysis in the presence of New Physics, improving the bounds coming from B_{(s)}-\bar B_{(s)} mixing. |
| Copyright/License | publication: © 2014-2025 The Author(s) (License: CC-BY-4.0), sponsored by SCOAP³ preprint: © 2013-2025 CERN (License: CC-BY-3.0) |
Corresponding record in: Inspire
Element opprettet 2013-08-09, sist endret 2023-06-28
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