B meson semileptonic form factors from unquenched lattice QCD

Journal Article · Sat Apr 01 00:00:00 EST 2006 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.73.074502· OSTI ID:20782821

Gulez, Emel; Gray, Alan; Shigemitsu, Junko ^[1]; Wingate, Matthew ^[2]; Davies, Christine T. H. ^[3]; Lepage, G Peter ^[4]

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1. Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States)
2. Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1550 (United States)
3. Department of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ (United Kingdom)
4. Laboratory of Elementary Particle Physics, Cornell University, Ithaca, New York 14853 (United States)

The semileptonic process, B{yields}{pi}l{nu}, is studied via full QCD lattice simulations. We use unquenched gauge configurations generated by the MILC Collaboration. These include the effect of vacuum polarization from three quark flavors: the s quark and two very light flavors (u/d) of variable mass allowing extrapolations to the physical chiral limit. We employ nonrelativistic QCD to simulate the b quark and a highly improved staggered quark action for the light sea and valence quarks. We calculate the form factors f{sub +}(q{sup 2}) and f{sub 0}(q{sup 2}) in the chiral limit for the range 16 GeV{sup 2}{<=}q{sup 2}<q{sub max}{sup 2} and obtain 16 GeV{sup 2}({integral}(q{sub max}{sup 2}))[d{gamma}/dq{sup 2}]dq{sup 2}/V{sub ub}{sup 2}=1.46(35) ps{sup -1}. Combining this with a preliminary average by the Heavy Flavor Averaging Group (HFAG'05) of recent branching fraction data for exclusive B semileptonic decays from the BABAR, Belle and CLEO Collaborations leads to V{sub ub}=4.22(30)(51)x10{sup -3}.

• OSTI ID: 20782821
• Journal Information: Physical Review. D, Particles Fields, Vol. 73, Issue 7; Other Information: DOI: 10.1103/PhysRevD.73.074502; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
B QUARKS
BRANCHING RATIO
CESR STORAGE RING
CHIRAL SYMMETRY
CHIRALITY
COMPUTERIZED SIMULATION
EXTRAPOLATION
FLAVOR MODEL
FORM FACTORS
LATTICE FIELD THEORY
MULTIPARTICLE SPECTROMETERS
PARTICLE IDENTIFICATION
QUANTUM CHROMODYNAMICS
REST MASS
S QUARKS
SEMILEPTONIC DECAY
VACUUM POLARIZATION
VALENCE