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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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DOE OSTI2011

In-Medium QCD Sum Rules for {rho}-Meson and Chiral Scale

In this talk, chiral scale, 4{pi}f{sub {pi}{approx}1} GeV, was introduced as an indicator of partial restoration of chiral symmetry at finite density or temperature, rather than the argument between mass shift and collisional broadening. We use the finite energy sum rules to determine the chiral scale identified with the separation scale of the low-energy resonance part from the high-energy continuum part of {rho}-meson spectral function. In this framework, in-medium {rho}-meson mass should be discussed in terms of the first two moments of the spectral function.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Search for charmonium and charmoniumlike states in Υ ( 2 S ) radiative decays

Using a sample of 158 x 10⁶ Υ(2S) events collected with the Belle detector, charmonium and charmoniumlike states with even charge parity are searched for in Υ(2S) radiative decays. No significant Xcl or nc signal is observed, and the following upper limits at 90% confidence level (C. L.) are obtained: Β(Υ(2S)→YXco)<1.0×10 - ⁴, Β(Υ(2S)→yxc1)<3.6×10 - ⁶, Β(Υ(2S)→yxc2)<1.5 x 10 - ⁵, and Β(Υ(2S)→ync)<2.7×10 - ⁵. No significant signal of any charmoniumlike state is observed, and we obtain the limits Β(Υ(2S)→yX(3872)) x Β(X(3872)→π⁺π⁻J/ψ)<0.8×10-6, Β(Υ(2S)→γX(3872))× Β(X(3872)→ π⁺π⁻π⁰Jlψ)<2.4 x 10⁻⁶, Β(Υ(2S)→γX(3915))× Β(X(3915)→ωJ/ψ)<2.8×10⁻⁶, Β(Υ(2S)→γY(4140)) x Β(Y(4140)→$\phi$J/ψ))<1.2 x 10 - ⁶, and Β(Υ(2S)→yX(4350))× Β(X(4350)→$\phi$J/ψ))<1.3×10⁻⁶ at 90% C. L.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Observation of the Rare Decay B+ \to K+pi0pi0 and Measurement of the Quasi-two Body Contributions B+ \to K*(892)+pi0, B+ \to f0(980)K+ and B+ \to chic0K+

We report an analysis of charmless hadronic decays of charged B mesons to the final state K{sup +}{pi}{sup 0}{pi}{sup 0}, using a data sample of (470.9 {+-} 2.8) x 10{sup 6} B{bar B} events collected with the BABAR detector at the {Gamma}(4S) resonance. We observe an excess of signal events, with a significance above 10 standard deviations including systematic uncertainties, and measure the branching fraction and CP asymmetry to be {Beta}(B{sup +} {yields} K{sup +}{pi}{sup 0}{pi}{sup 0}) = (16.2 {+-} 1.2 {+-} 1.5) x 10{sup -6} and A{sub CP}(B{sup +} {yields} K{sup +}{pi}{sup 0}{pi}{sup 0}) = -0.06 {+-} 0.06 {+-} 0.04, where the uncertainties are statistical and systematic, respectively. Additionally, we study the contributions of the B{sup +} {yields} K{sup +}(892){sup +}{pi}{sup 0}, B{sup +} {yields} f{sub 0}(980)K{sup +}, and B{sup +} {yields} {chi}{sub c0}K{sup +} quasi-two-body decays. We report the world's best measurements of the branching fraction and CP asymmetry of the B{sup +} {yields} K{sup +}{pi}{sup 0}{pi}{sup 0} and B{sup +} {yields} K{sup +}(892){sup +}{pi}{sup 0} channels.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2012

Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar

We present experimental measurements of branching fraction and longitudinal polarization fraction in charmless hadronic B decays into vector, axial vector and tensor final states with the final dataset of BABAR. Measurements of such kind of decays are a powerful tool both to test the Standard Model and search possible sources of new physics. In this document we present a short review of the last experimental results at BABAR concerning charmless quasi two-body decays in final states containing particles with spin 1 or spin 2 and different parities. This kind of decays has received considerable theoretical interest in the last few years and this particular attention has led to interesting experimental results at the current b-factories. In fact, the study of longitudinal polarization fraction f{sub L} in charmless B decays to vector vector (VV), vector axial-vector (VA) and axial-vector axial-vector (AA) mesons provides information on the underlying helicity structure of the decay mechanism. Naive helicity conservation arguments predict a dominant longitudinal polarization fraction f{sub L} {approx} 1 for both tree and penguin dominated decays and this pattern seems to be confirmed by tree-dominated B {yields} {rho}{rho} and B{sup +} {yields} {Omega}{rho}{sup +} decays. Other penguin dominated decays, instead, show a different behavior: the measured value of f{sub L} {approx} 0.5 in B {yields} {phi}K* decays is in contrast with naive Standard Model (SM) calculations. Several solutions have been proposed such as the introduction of non-factorizable terms and penguin-annihilation amplitudes, while other explanations invoke new physics. New modes have been investigated to shed more light on the problem.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

N* production from pp and p-barp collisions

With an effective Lagrangian approach, we give a full analysis on the NN{yields}NN{pi}{pi} and pp{yields}pn{pi}{sup +} reactions for proton beam energy from 1 to 1.5 GeV. The results are very consistent with the experiment data from CELSIUS, KEK, COSY, and so on. Based on these results, we consider the N-barN{yields}N-barN{pi}{pi} and p-barp{yields}p-barn{pi}{sup +} for proton beam energy up to 4 GeV. Compare to the pp collisions, there are many benefits to study N* resonances in these two reactions. And for the high proton beam energy up to 15 GeV, we consider some new resonances with hidden charm which are definitely beyond three constituent quarks model in the p-barp{yields}p-barpJ/{psi} and p-barp{yields}p-barp{eta}{sub c}, where there are very nice places to find these new N{sub cc}-bar*. The predicted results about p-barp collisions can be looked for at the forthcoming PANDA/FAIR experiments.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Binding Energies of Hyperonic Matter and Applications to Neutron Stars

The conserving nonlinear, nonchiral {sigma}-{omega}-{rho} hadronic mean-field approximation is applied to saturation properties of nuclear and hyperonic matter, properties of hadron and hadron-quark neutron stars. Nonlinear interactions are renormalized self-consistently as effective coupling constants, effective masses, and sources of equations of motion by maintaining thermodynamic consistency to the mean-field approximation. The effective masses and coupling constants become density-dependent, and they simultaneously determine binding energies and saturation properties of nuclear matter and hyperonic matter. The conserving nonlinear {sigma}-{omega}-{rho} mean-field approximation with vacuum fluctuation corrections and strange quark matter defined by the MIT-bag model were employed to examine properties of hadron-(strange) quark stars. We found that hadron-quark stars become more stable at high densities compared to pure hadronic and strange quark stars.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Influence of nucleus potential on kaon and antikaon pairs decayed from short lived particles in a nucleus

We propose a possible way to probe the interactions of kaon- and antikaon-nucleus by measuring K{sup +}K{sup -} pairs decayed from {phi}(1020) meson in a nuclear target. The K{sup +}K{sup -} pairs emerged from nuclei can be affected by hadronic potentials and the difference of kaon- and antikaon-nucleus potential maybe modify invariant masses of K{sup +}K{sup -} decayed from {phi} mesons. The {phi} mesons can be produced with a lead target for the energy region 1.5{approx}2.4 GeV at LEPS facility in Super Photon Ring 8-GeV (Spring-8). By comparing results of Monte Carlo calculation with experimental data, we can probe kaon-, and antikaon-nucleus potential.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Nuclear medium effects in {nu}/{nu}-bar-A DIS

Nuclear medium effects in the weak structure functions F{sub 2}(x,Q{sup 2}) and F{sub 3}(x,Q{sup 2}) have been studied for deep inelastic neutrino/antineutrino reactions in iron nucleus by taking into account Fermi motion, binding, pion and rho meson cloud contributions, target mass correction, shadowing and anti-shadowing corrections. The calculations have been performed in a local density approximation using relativistic nuclear spectral functions which include nucleon correlations. Using these structure functions we have obtained the ratio R{sub F2,F3}{sup A}(x,Q{sup 2}) = (2F{sub 2,3}{sup A}(x,Q{sup 2})/AF{sub 2,3}{sup D}(x,Q{sup 2})), the differential scattering cross section (1/E)(d{sup 2}{sigma}/dxdy) and the total scattering cross section {sigma}. The results of our numerical calculations in {sup 56}Fe are compared with the experimental results of NuTeV and CDHSW collaborations.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Radiative {phi}{yields}{sigma}{gamma} Vertex in QCD Sum Rules and Phenomenological Approach

We estimate the coupling constant g{sub {phi}{sigma}{gamma}} by using the three-point correlation function and we also investigate this coupling constant by studying the effective lagrangians. Here we consider the effect the {phi}-{omega} mixing effect to the calculation. Besides, a comparison of our predictions with the theoretical results existing in literature is presented.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Measuring the fourth-generation b{yields}s quadrangle at the LHC

We show that simultaneous precision measurements of the CP-violating phase in time-dependent B{sub s}{yields}J/{psi}{phi} study and the B{sub s}{yields}{mu}{sup +}{mu}{sup -} rate, together with measuring m{sub t'} by direct search at the LHC, would determine V{sub t's}*V{sub t'b} and therefore the b{yields}s quadrangle in the four-generation standard model. The forward-backward asymmetry in B{yields}K*l{sup +}l{sup -} provides further discrimination.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2025

𝐵 → 𝜌⁢ℓ⁢$\bar{v}$ Resonance Form Factors from 𝐵→ 𝜋⁢𝜋⁢ℓ⁢$\bar{v}$ in Lattice QCD

The decay 𝐵 → 𝜌⁢ℓ⁢$\bar{v}$ is an attractive process for determining the magnitude of the smallest Cabibbo-Kobayashi-Maskawa matrix element, |𝑉 𝑢⁢𝑏 |, and can provide new insights into the origin of the long-standing exclusive-inclusive discrepancy in determinations of this standard-model parameter. This requires a nonperturbative QCD calculation of the 𝐵 → 𝜌 form factors 𝑉, 𝐴 0 , 𝐴 1 , and 𝐴 12 . The unstable nature of the 𝜌 resonance has prevented precise lattice QCD calculations of these form factors to date. Here, we present the first lattice QCD calculation of the 𝐵 → 𝜌 form factors in which the 𝜌 is treated properly as a resonance in 𝑃-wave 𝜋⁢𝜋 scattering. To this end, we use the Lellouch-Lüscher finite-volume formalism to compute the 𝐵 → 𝜋⁢𝜋 form factors as a function of both momentum transfer and 𝜋⁢𝜋 invariant mass, and then analytically continue to the 𝜌 resonance pole. This calculation is performed with 2 + 1 dynamical quark flavors at a pion mass of approximately 320 MeV, and demonstrates a clear path toward results at the physical point.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Masses of vector bosons in two-color dense QCD based on the generalized hidden local symmetry

We study the dependence of 'vector' and 'axial-vector' boson masses (mesons and diquark baryons with J{sup P} = 1{sup {+-}} on the baryon density {mu}{sub B} for two-color QCD. We show that the baryonic axial-vector boson has a finite vacuum expectation value (VEV) at the finite {mu}{sub B} where the U(1){sub B} symmetry is spontaneously broken. We also find that the VEV causes the mixing between 'vector' and 'axial-vector' bosons. As a result of the mixing, our model can reproduce the {mu}{sub B} dependence of '(axial-) vector' boson masses shown by the lattice data.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Heavy Quark Hadrons and Exotics a challenge for QCD

Exotic hadrons with heavy quarks can confirm in the same multiquark system that the qq-bar interaction is much stronger than the qq interaction and produces color structures totally different from those of normal hadrons. Unusual heavy tetraquark structure may explain unusual properties of newly discovered mesons like the X(3872). Both charged and neutral B decays produce this narrow neutral resonant state that decays to both J/{psi}{rho} and J/{psi}{omega}, while no charged resonances in the same multiplet are found. This suggests that the X is an isoscalar resonance whose production conserves isospin, while isospin is violated only in the decay by an electromagnetic interaction allowing the isospin-forbidden J/{psi}{rho} decay. New data for X production in B decays provide a separation between production and decay, sharpen several experimental puzzles and impose serious constraints on all models. A proposed isoscalar tetraquark model agrees with all present data, conserves isospin in its production and breaks isospin only in an electromagnetic X(3872)J/{psi}{rho}{sup o} decay. The narrow X decay width results from the tiny phase space available for the J/{psi}{omega} decay and enables competition with the electromagnetic isospin-forbidden J/{psi}{rho} decay which has much larger phase space. Experimental tests are proposed for this isospin production invariance.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Extended Chiral ({sigma},{pi},{omega}) Mean-Field Model with Vacuum Fluctuation Corrections

Density-dependent relations among saturation properties of symmetric nuclear matter and properties of hadronic stars are discussed by applying the conserving chiral nonlinear ({sigma},{pi},{omega}) mean-field theory. The chiral nonlinear ({sigma},{pi},{omega}) mean-field theory is an extension of the conserving nonlinear (nonchiral){sigma}-{omega} mean-field theory, which is thermodynamically consistent, relativistic and Lorentz-covariant. In the extended chiral ({sigma},{pi},{omega}) mean-field model, all the masses of hadrons are produced by the spontaneous chiral symmetry breaking, which is different from conventional chiral partner models. By comparing both nonchiral and chiral mean-field approximations, the effects of the chiral symmetry breaking mechanism on the mass of {sigma}-meson, coefficients of nonlinear interactions and Fermi-liquid properties are investigated in nuclear matter and neutron stars.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Revisit the radiative decays of J/{psi} and {psi}{sup '}{yields}{gamma}{eta}{sub c}({gamma}{eta}{sub c}{sup '})

With the new measurements of J/{psi} and {psi}{sup '}{yields}{gamma}{eta}{sub c}({gamma}{eta}{sub c}{sup '}) from the CLEO and BES-III collaboration, we reinvestigate the intermediate meson loop (IML) contributions to these radiative decays in association with the quark model M1 transitions in an effective Lagrangian approach. It shows that the ''unquenched'' effects due to the intermediate hadron loops can be better quantified by the new data for J/{psi}{yields}{gamma}{eta}{sub c}. Although the IML contributions are relatively small in J/{psi}{yields}{gamma}{eta}{sub c}, they play a crucial role in {psi}{sup '}{yields}{gamma}{eta}{sub c}({gamma}{eta}{sub c}{sup '}). A prediction for the IML contributions to {psi}(3770){yields}{gamma}{eta}{sub c}({gamma}{eta}{sub c}{sup '}) is made. Such unquenched effects allow us to reach a coherent description of those three radiative transitions, and gain some insights into the underlying dynamics.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

{rho} meson decay in 2+1 flavor lattice QCD

We perform a lattice QCD study of the {rho} meson decay from the N{sub f}=2+1 full QCD configurations generated with a renormalization group improved gauge action and a nonperturbatively O(a)-improved Wilson fermion action. The resonance parameters, the effective {rho}{yields}{pi}{pi} coupling constant and the resonance mass, are estimated from the P-wave scattering phase shift for the isospin I=1 two-pion system. The finite size formulas are employed to calculate the phase shift from the energy on the lattice. Our calculations are carried out at two quark masses, m{sub {pi}=}410 MeV (m{sub {pi}/}m{sub {rho}=}0.46) and m{sub {pi}=}300 MeV (m{sub {pi}/}m{sub {rho}=}0.35), on a 32{sup 3}x64 (La=2.9 fm) lattice at the lattice spacing a=0.091 fm. We compare our results at these two quark masses with those given in the previous works using N{sub f}=2 full QCD configurations and the experiment.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗