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The precision of lattice QCD calculations has been steadily improving for some time and is now approaching, or has surpassed, the 1% level for multiple quantities. At this level QED effects, i.e. the fact that quarks carry electric as well as color charge, come into play. In this report we will summarise results from the first lattice QCD+QED computations of the properties of ground-state charmonium and bottomonium mesons by the HPQCD Collaboration.

We use our lattice QCD computation of the B_{c}→J/ψ form factors to determine the differential decay rate for the semitauonic decay channel and construct the ratio of branching fractions R(J/ψ)=B(B_{c}^{-}→J/ψτ^{-}ν[over ¯]_{τ})/B(B_{c}^{-}→J/ψμ^{-}ν[over ¯]_{μ}). We find R(J/ψ)=0.2582(38) and give an error budget. We also extend the relevant angular observables, which were recently suggested for the study of lepton flavor universality violating effects in B→D^{*}ℓν, to B_{c}→J/ψℓν and make predictions for their values under different new physics scenarios.

Predicting the B_{s}^{0}-B[over ¯]_{s}^{0} width difference ΔΓ_{s} relies on the heavy quark expansion and on hadronic matrix elements of ΔB=2 operators. We present the first lattice QCD results for matrix elements of the dimension-7 operators R_{2,3} and linear combinations R[over ˜]_{2,3} using nonrelativistic QCD for the bottom quark and a highly improved staggered quark (HISQ) action for the strange quark. Computations use MILC Collaboration ensembles of gauge field configurations with 2+1+1 flavors of sea quarks with the HISQ discretization, including lattices with physically light up or down quark masses. We discuss features unique to calculating matrix elements of these operators and analyze uncertainties from series truncation, discretization, and quark mass dependence. Finally we report the first standard model determination of ΔΓ_{s} using lattice QCD results for all hadronic matrix elements through O(1/m_{b}). The main result of our calculations yields the 1/m_{b} contribution ΔΓ_{1/m_{b}}=-0.022(10) ps^{-1}. Adding this to the leading order contribution, the standard model prediction is ΔΓ_{s}=0.092(14) ps^{-1}.

Calculations of pseudoscalar decay constants of B, Bs, K and p mesons with physical light quarks are presented. We use HISQ ensembles that include u;d;s and c sea quarks at three lattice spacings. HISQ is used for the valence light quarks and a radiatively improved NRQCD action for the heavy quarks. The key results are fB+ = 0:184(4) GeV, fBs = 0:224(4) GeV, fBs=fB+ = 1:217(8), f K+=f p+ = 1:1916(21), f K+ = 155:37(34) MeV, giving a significant improvement over previous results that required chiral extrapolation. We also calculate the Wilson flow scale w0, finding w0 = 0:1715(9) fm.

As part of a three year study of the use of reed beds for the treatment of wastewater, two pilot scale constructed wetlands (30m × 5m), one planted with Phragmites australis and the other serving as an unplanted control, were used to treat primary domestic sewage. This paper describes an experiment conducted to test the hypothesis that increasing available oxygen by aeration of the wastewater in the treatment beds could increase nitrification, and hopefully nitrogen removal rates. Prior to aeration, the influent nitrogen load in the wastewater passing through the beds was reduced by approximately 45% and 10% in the planted and control beds respectively. With aeration of the wastewater as it passed through each bed, nitrogen removal was approximately 51% and 20% for the planted and control beds respectively. High rates of nitrification were recorded for the planted bed with aeration, but removal of nitrogen by denitrification was limited, probably because of the absence of a suitable carbon source (indicat...

We present the first lattice QCD calculation of the decay constants f(B) and f(B(s)) with physical light quark masses. We use configurations generated by the MILC Collaboration including the effect of u, d, s, and c highly improved staggered quarks in the sea at three lattice spacings and with three u/d quark mass values going down to the physical value. We use improved nonrelativistic QCD (NRQCD) for the valence b quarks. Our results are f(B)=0.186(4) GeV, f(B(s))=0.224(4) GeV, f(B(s))/f(B)=1.205(7), and M(B(s))-M(B)=85(2) MeV, superseding earlier results with NRQCD b quarks. We discuss the implications of our results for the standard model rates for B((s))→μ(+)μ(-) and B→τν.

Five experiments were carried out to measure the effects of seed rate and fertilizers on the establishment and early growth of reseeded grass mixtures in the Falkland Islands. Experiments 1 and 2 compared seed rates within the range 7·5-35kg ha−1. Experiment 3 assessed the effects of three levels of each of nitrogen (N), P2O5, K2O and CaCO3 applied as seedbed fertilizers. Experiments 4 and 5 were similar in intent to Experiment 3, but treatments consisted of either nil or a very heavy application of the same fertilizer elements. In all experiments, the grass seed mixtures were sown in late summer after rotavation and burning of Cortaderia pilosa dominant indigenous vegetation on peaty soils. Percentage ground cover was estimated in the following spring and dry matter production through the first year was determined by sample harvests. Initially, heavier seed rates resulted in higher percentage ground cover of sown species, but dry matter production over the season following sowing showed a significant increase only between the 25 and 35 kg ha−1 rates in Experiment 2. The modest levels of seedbed fertilizers applied in Experiment 3 had no significant effect on either percentage ground cover of sown species or dry matter production. Even at the higher levels used in Experiments 4 and 5, only N consistently increased dry matter yields, although a significant positive response was also obtained from CaCO3 in the final harvests. The implications of the results to farmers in the Falkland Islands who may be contemplating reseeding are discussed.

Constructed wetlands bave the capability to treat industrial wastewater containing a wide range of chemicals, including priority pollutants such as phenols and cresols, by processes such as absorption and bacterial breakdown, chemical oxidation, adsorption onto the bed matrix and sedimentation. A brief overview of this technique is presented along with details of preliminary trials carried out on textile dyeing and processing water. The trials were conducted in a horizontal flow, gravel bed reed (30m × 5m), located in Melbourne, Australia. The textile dye wastewater was applied at an influent rate of 10 1/min., resulting in a retention time in the reed beds of 3–4 days, results indicated that breakdown of the visible dye occurred mainly in the first one third of the bed.

The inertia of the moving parts of high-speed planar mechanisms creates a shaking force that is variable in magnitude, direction and line of action throughout a cycle. Alternatively, the instantaneous shaking force vector can be represented by an equal parallel force acting through an arbitrarily chosen origin, together with a moment about that origin. The two components of the force and the moment can be computed by kinetostatic analysis at discrete intervals of a cycle to create three arrays. The discrete Fourier transform converts these arrays from the time to the frequency domain. The lowest frequency term of order k = 1 is of cycle frequency. Terms of higher order k > 1 have frequencies that are k times cycle frequency. The shaking force frequency term of order k can be represented by two contra-rotating force vectors of constant, but generally unequal, magnitude rotating at k times cycle frequency. The forces can be eliminated by equal and opposite forces exerted by counterweights mounted on contra-rotating shafts rotating at the same speed. However, if the locations of these shafts are both arbitrarily chosen, a shaking couple of order k will generally remain unbalanced. Fast Fourier transform (FFT) analysis of the array of moments as well as the force components enables suitable shaft locations to be determined in such a way that this couple vanishes. The couple vanishes if the balancing shafts are coaxial with a centre at an invariant location in the plane. The couple can also be eliminated even though the location of either shaft, but not both, is chosen arbitrarily. The location of the second shaft is then determinate and two procedures are explained to determine that location.

We determine D and D(s) decay constants from lattice QCD with 2% errors, 4 times better than experiment and previous theory: f(D(s))=241(3) MeV, f(D)=207(4) MeV, and fD(s))/f(D)=1.164(11). We also obtain f(K)/f(pi)=1.189(7) and (f(D(s))/f(D))/(f(K)/f(pi))=0.979(11). Combining with experiment gives V(us)=0.2262(14) and V(cs)/V(cd) of 4.43(41). We use a highly improved quark discretization on MILC gluon fields that include realistic sea quarks, fixing the u/d, s, and c masses from the pi, K, and eta(c) meson masses. This allows a stringent test against experiment for D and D(s) masses for the first time (to within 7 MeV).

We obtain a new value for the QCD coupling constant by combining lattice QCD simulations with experimental data for hadron masses. Our lattice analysis is the first to (1) include vacuum polarization effects from all three light-quark flavors (using MILC configurations), (2) include third-order terms in perturbation theory, (3) systematically estimate fourth and higher-order terms, (4) use an unambiguous lattice spacing, and (5) use an [symbol: see text](a2)-accurate QCD action. We use 28 different (but related) short-distance quantities to obtain alpha((5)/(MS))(M(Z)) = 0.1170(12).

Capitalizing on recent advances in lattice QCD, we present a calculation of the leptonic decay constants f(B(s)) and f(D(s)) that includes effects of one strange sea quark and two light sea quarks via an improved staggered action. By shedding the quenched approximation and the associated lattice scale uncertainty, lattice QCD greatly increases its predictive power. Nonrelativistic QCD is used to simulate heavy quarks with masses between 1.5m(c) and m(b). We arrive at the following results: f(B(s))=260+/-7+/-26+/-8+/-5 and f(D(s))=290+/-20+/-29+/-29+/-6 MeV. The first quoted error is the statistical uncertainty, and the rest estimate the sizes of higher order terms neglected in this calculation. All of these uncertainties are systematically improvable by including another order in the weak coupling expansion, the nonrelativistic expansion, or the Symanzik improvement program.

A study has been made of recoil halogen species ejected from gaseous ethyl bromide and iodide after neutron capture. The results demonstrate that a fraction of the radio‐halide fragments carry a positive charge. The fraction charged is 12 percent for the 4.4‐hr Br80m, 25 percent for the 36‐hr Br82, and 50 percent for the 25‐min I128. The corresponding estimate for the 18‐min Br80 is very approximately 18 percent. The positive charges are attributed to internal conversion processes in the stabilization of the compound nucleus formed by neutron capture. The fraction of positive recoil ions is interpreted as the minimum fraction of neutron capture processes which are followed by an internal conversion process. A comment is made upon the possible significance of the ions in the study of chemical reactions induced by radiative neutron capture.A study of the 18‐min Rb88 from β‐decay of the 2.8‐hr Kr88 was made using the procedures and equipment employed in the halogen experiments. The results show that all Rb88 atoms are positively charged as expected.

Considerable improvement has been achieved in rough grazings by fairly frequent close mowing with the forage harvester or flail mower, particularly when combined with manuring and surface seeding. The implement has proved capable of tackling very tough vegetation and converting it into grazing swards of fair value and good botanical composition. Undesirable species have been largely eliminated by treatment over two growing seasons. The method is believed to compare favourably in cost with sward renovation by cultivation or by herbicides.

The concept of glass as a polymer of silicon, phosphorus, or other glassforming atoms connected by oxygen atoms suggests that fibers with oriented linear chains may be prepared. Previous attempts to demonstrate such orientation have failed, however, with glasses of the usual compositions. The composition in which linear chains seem most likely to occur is that of the “meta” salts in which each glassformer is bound, on the average, to two others through oxygen atoms. Under drawing conditions indicated by the theory of viscoelastic properties of high polymers, fibers of sodium metaphosphate glass have been prepared that show birefringence and give X-ray diffraction patterns similar to those of organic fibers with oriented chain molecules. Under analogous treatment sodium metasilicate failed to give such effects.

A list of 134 species of Mycetophilidae and Sciaridae (Diptera) is given with notes on abundance or scarcity in relation to trap catches only, and at 1 particular site.

The space between two concentric copper‐amalgam electrodes was filled to several microns pressure with ethyl bromide containing 4.4‐hr. Br80*. The distribution between electrode surfaces of 18‐min. Br80 dissociated from ethyl bromide in consequence of the isomeric transition process was determined. The results establish the presence of positively charged 18‐min. Br80 species among the decay products. At least 50 percent of the dissociations yield positive Br80 species. The remainder yield uncharged Br80 species.

This editorial analysis and comment introduces the materials relevant to the Oak Ridge “Security Risk” cases presented on the following six pages of the BULLETIN. Dr. Davies is assistant professor of chemistry and member of the Institute for Nuclear Studies at the University of Chicago.