J. Foley

Symanzik flow on HISQ ensembles

The MILC Collaboration, A. Bazavov, C. Bernard +13

We report on a scale determination with gradient-flow techniques on the $N_{f} = 2 + 1 + 1$ HISQ ensembles generated by the MILC collaboration. The lattice scale $w_{0} / a$ , originally…

The $D_{s}$ , $D^{+}$ , $B_{s}$ and $B$ decay constants from $2 + 1$ flavor lattice QCD

A. Bazavov, C. Bernard, C. Bouchard +23

We present a study of the $D$ and $B$ leptonic decay constants on the MILC $N_{f} = 2 + 1$ asqtad gauge ensembles using asqtad-improved staggered light quarks and clover heavy quarks in…

Charmed and light pseudoscalar meson decay constants from four-flavor lattice QCD with physical light quarks

A. Bazavov, C. Bernard, C. M. Bouchard +20

We compute the leptonic decay constants $f_{D^{+}}$ , $f_{D_{s}}$ , and $f_{K^{+}}$ , and the quark-mass ratios $m_{c} / m_{s}$ and $m_{s} / m_{l}$ in unquenched lattice QCD using the experimentally de…

Two-point Correlator Fits on HISQ Ensembles

A. Bazavov, C. Bernard, C. Bouchard +22

We present our methods to fit the two point correlators for light, strange, and charmed pseudoscalar meson physics with the highly improved staggered quark (HISQ) action. We make u…

Extended hadron and two-hadron operators of definite momentum for spectrum calculations in lattice QCD

C. Morningstar, J. Bulava, B. Fahy +5

Multi-hadron operators are crucial for reliably extracting the masses of excited states lying above multi-hadron thresholds in lattice QCD Monte Carlo calculations. The constructio…

Heavy-meson semileptonic decays for the Standard Model and beyond

Yuzhi Liu, Ran Zhou, Jon A. Bailey +25

We calculate the form factors for the semileptonic decays $B_{s} \to K ℓ I^½$ and $B \to K ℓℓ$ with lattice QCD. We work at several lattice spacings and a range of light quark mas…

hep-ph2012

Refining new-physics searches in B -> D tau nu decay with lattice QCD

Jon A. Bailey, A. Bazavov, C. Bernard +23

The semileptonic decay channel B -> D tau nu is sensitive to the presence of a scalar current, such as that mediated by a charged-Higgs boson. Recently the BaBar experiment reporte…

hep-ph2014

Determination of $∣ V_{u s} ∣$ from a lattice-QCD calculation of the $K \to I ¨ ℓ I^½$ semileptonic form factor with physical quark masses

A. Bazavov, C. Bernard, C. Bouchard +21

We calculate the kaon semileptonic form factor $f_{+} (0)$ from lattice QCD, working, for the first time, at the physical light-quark masses. We use gauge configurations generated by…

Kaon semileptonic decay form factors with HISQ valence quarks

E. Gamiz, J. A. Bailey, A. Bazavov +22

We report on the status of our kaon semileptonic form factor calculations using the highly-improved staggered quark (HISQ) formulation to simulate the valence fermions. We present…

Kaon semileptonic vector form factor and determination of |V_{us}| using staggered fermions

A. Bazavov, C. Bernard, C. M. Bouchard +21

Using staggered fermions and twisted boundary conditions, we calculate the K meson semileptonic decay vector form factor at zero momentum transfer. The HISQ formulation is used for…

Electromagnetic contributions to pseudoscalar masses

S. Basak, A. Bazavov, C. Bernard +16

We report on the calculation by the MILC Collaboration of the electromagnetic effects on kaon and pion masses. These masses are computed in QCD with dynamical (asqtad staggered) qu…

hep-lat2016

Electromagnetic effects on the light pseudoscalar mesons and determination of $m_{u} / m_{d}$

MILC Collaboration, S. Basak, A. Bazavov +15

The MILC Collaboration has completed production running of electromagnetic effects on light mesons using asqtad improved staggered quarks. In these calculations, we use quenched ph…

Charmed and light pseudoscalar meson decay constants from HISQ simulations

A. Bazavov, C. Bernard, C. Bouchard +20

We compute the leptonic decay constants $f_{D^{+}}$ , $f_{D_{s}}$ , and $f_{K^{+}}$ , and the quark-mass ratios $m_{c} / m_{s}$ and $m_{s} / m_{l}$ in unquenched lattice QCD. We use the MILC highly imp…

hep-ph2013

Leptonic decay-constant ratio f_{K^+}/f_{pi^+} from lattice QCD with physical light quarks

A. Bazavov, C. Bernard, C. DeTar +15

A calculation of the ratio of leptonic decay constants f_{K^+}/f_{Ï^+} makes possible a precise determination of the ratio of CKM matrix elements |V_{us}|/|V_{ud}| in the Standard…

hep-lat2015

Electromagnetic effects on the light hadron spectrum

MILC Collaboration, S. Basak, A. Bazavov +16

For some time, the MILC Collaboration has been studying electromagnetic effects on light mesons. These calculations use fully dynamical QCD, but only quenched photons, which suffic…

Multi-hadron states in Lattice QCD spectroscopy

J. Foley, J. Bulava, K. J. Juge +3

The ability to reliably measure the energy of an excited hadron in Lattice QCD simulations hinges on the accurate determination of all lower-lying energies in the same symmetry cha…

hep-lat2011

A novel algorithm for computing quark propagators for lattice hadron spectroscopy

J. Bulava, J. Foley, Y. C. Jhang +5

We report on our progress in computing the excitation spectrum in Lattice QCD. We focus on the isospin 0, 1 and 2 channels using the stochastic LapH algorithm for the quark propaga…

Status of the MILC calculation of electromagnetic contributions to pseudoscalar masses

S. Basak, A. Bazavov, C. Bernard +16

We calculate pseudoscalar masses on gauge configurations containing the effects of 2+1 flavors of dynamical asqtad quarks and quenched electromagnetism. The lattice spacings vary f…

Polarised correlators at finite temperature

G. Aarts, C. R. Allton, S. J. Hands +2

QCD undergoes a deconfining transition at high temperature to a "quark-gluon plasma" phase where hadrons may become unbound. In this work, meson correlation functions at non-zero m…

hep-lat2011

Progress Report on Computing Excited-State Hadron Masses in Lattice QCD

C. Morningstar, A. Bell, J. Bulava +4

Our progress in computing the spectrum of excited baryons and mesons in lattice QCD is described. Sets of spatially-extended hadron operators with a variety of different momenta ar…

hep-lat2011

Excited-State Hadrons using the Stochastic LapH Method

C. Morningstar, A. Bell, J. Bulava +4

Progress in computing the spectrum of excited baryons and mesons in lattice QCD is described. Large sets of spatially-extended hadron operators are used. A new method of stochastic…

Update of $∣ V_{c b} ∣$ from the $B ˉ \to D^{*} ℓ I^ˉ ½$ form factor at zero recoil with three-flavor lattice QCD

Jon A. Bailey, A. Bazavov, C. Bernard +20

We compute the zero-recoil form factor for the semileptonic decay $B ˉ^{0} \to D^{*+} ℓ^{-} I^ˉ ½$ (and modes related by isospin and charge conjugation) using lattice QCD with thr…

K semileptonic form factor with HISQ fermions at the physical point

E. GÃ¡miz, A. Bazavov, C. Bernard +21

We present results for the form factor $f_{+}^{K I ¨ } (0)$ , needed to extract the CKM matrix element $∣ V_{u s} ∣$ from experimental data on semileptonic $K$ decays, on the HISQ $N_f=2+1+…

Pseudoscalar meson physics with four dynamical quarks

A. Bazavov, C. Bernard, C. Bouchard +22

We present preliminary results for light, strange and charmed pseudoscalar meson physics from simulations using four flavors of dynamical quarks with the highly improved staggered…

Finite-volume effects and the electromagnetic contributions to kaon and pion masses

S. Basak, A. Bazavov, C. Bernard +14

We report on the MILC Collaboration calculation of electromagnetic effects on light pseudoscalar mesons. The simulations employ asqtad staggered dynamical quarks in QCD plus quench…

The excited hadron spectrum in lattice QCD using a new variance reduction method

Colin Morningstar, A. Bell, C. Y. Chen +6

Progress in calculating the spectrum of excited baryons and mesons in lattice QCD is described. Correlation matrices of sets of spatially-extended hadron operators have been studie…

$B \to I ¨ ℓ I^½$ semileptonic form factors from unquenched lattice QCD and determination of $∣ V_{u b} ∣$

J. A. Bailey, A. Bazavov, C. Bernard +22

We compute the $B \to I ¨ ℓ I^½$ semileptonic form factors and update the determination of the CKM matrix element $∣ V_{u b} ∣$ . We use the MILC asqtad ensembles with $N_{f} = 2 + 1$ sea quark…

Charmed and strange pseudoscalar meson decay constants from HISQ simulations

A. Bazavov, C. Bernard, C. Bouchard +20

We update our determinations of $f_{D^{+}}$ , $f_{D_{s}}$ , $f_{K}$ , and quark mass ratios from simulations with four flavors of HISQ dynamical quarks. The availability of ensembles with l…

Update on the 2+1+1 flavor QCD equation of state with HISQ

A. Bazavov, C. Bernard, C. DeTar +11

We present recent results on the QCD equation of state with 2+1+1 flavors of highly improved staggered quarks (HISQ). We focus on three sets of ensembles with temporal extent 6, 8…

hep-lat2016

Gradient flow and scale setting on MILC HISQ ensembles

MILC Collaboration, A. Bazavov, C. Bernard +11

We report on a scale determination with gradient-flow techniques on the $N_{f} = 2 + 1 + 1$ highly improved staggered quark ensembles generated by the MILC Collaboration. The ensembles inc…

The excited hadron spectrum in lattice QCD using a new method of estimating quark propagation

C. Morningstar, A. Bell, J. Bulava +7

Progress in determining the spectrum of excited baryons and mesons in lattice QCD is described. Large sets of carefully-designed hadron operators have been studied and their effect…

hep-lat2016

$B \to K l^{+} l^{-}$ decay form factors from three-flavor lattice QCD

Jon A. Bailey, A. Bazavov, C. Bernard +24

We compute the form factors for the $B \to K l^{+} l^{-}$ semileptonic decay process in lattice QCD using gauge-field ensembles with 2+1 flavors of sea quark, generated by the MILC Colla…

B_s->D_s/B->D Semileptonic Form-Factor Ratios and Their Application to BR(B^0_s->Î¼^+Î¼^-)

Jon A. Bailey, A. Bazavov, C. Bernard +23

We calculate form-factor ratios between the semileptonic decays \bar{B}->D^+\ell^-\barÎ½ and \bar{B}_s->D_s^+\ell^-\barÎ½ with lattice QCD. These ratios are a key theoretical input…

hep-lat2015

The $B \to D ℓ I^½$ form factors at nonzero recoil and $∣ V_{c b} ∣$ from $2 + 1$ -flavor lattice QCD

Fermilab Lattice, MILC Collaborations, : +24

We present the first unquenched lattice-QCD calculation of the hadronic form factors for the exclusive decay $B \to D ℓ I^½$ at nonzero recoil. We car…