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Using lattice QCD simulations with $O(a)$-improved Wilson quarks and physical up, down and strange quark masses, we investigate the properties of thermal QCD matter at the temperatures $T=\{128,154,192\}\mathrm{MeV}$ with a fixed lattice spacing $a=0.064\mathrm{fm}$ and volume $V=(6.1\text{fm})^3$. We find that the pion quasiparticle, defined as the low-energy pole in the two-point function of the axial charge, becomes lighter as the temperature increases and give an argument based on hydrodynamics as to why the pole becomes purely diffusive above the chiral crossover. We study the thermal modification of the isovector vector spectral function using the Backus-Gilbert method, finding an enhancement at low energies and a depletion at energies around $1\mathrm{GeV}$.The analogous study of the axial-vector channel reveals a larger enhancement at energies below $1\mathrm{GeV}$, and we show that these findings are consistent with rigorous spectral sum rules. The difference between vector and axial-vector correlators, an order parameter for chiral symmetry, turns out to be overall suppressed by more than an order of magnitude at the crossover., Comment: 47 pages, 20 figures. arXiv admin note: text overlap with arXiv:2211.15558

The baryon masses on CLS ensembles are used to determine the LEC that characterize QCD in the flavor-SU(3) limit with vanishing up, down, and strange quark masses. Here we reevaluate some of the baryon masses on flavor-symmetric ensembles with much-improved statistical precision, in particular for the decuplet states. These additional results then lead to a more significant chiral extrapolation of the Lattice data set to its chiral SU(3) limit. Our results are based on the chiral Lagrangian with baryon octet and decuplet fields considered at the one-loop level. Finite-box and discretization effects of the Lattice data are considered systematically. While in our global fit of the data we insist on large-Nc sum rules for the LEC that enter at N3LO, all other LEC are unconstrained. In particular, we obtain values for the chiral limit of the pion decay constant and the isospin-limit of the quark-mass ratio compatible with the FLAG report., Comment: 30 pages, 6 figures and 11 tables, further two figures and tables. arXiv admin note: text overlap with arXiv:2301.06837

Phonetics is the scientific field concerned with the study of how speech is produced, heard and perceived. It abounds with data, such as acoustic speech recordings, neuroimaging data, or articulatory data. In this paper, we provide an introduction to different areas of phonetics (acoustic phonetics, sociophonetics, speech perception, articulatory phonetics, speech inversion, sound change, and speech technology), an overview of the statistical methods for analyzing their data, and an introduction to the signal processing methods commonly applied to speech recordings. A major transition in the statistical modeling of phonetic data has been the shift from fixed effects to random effects regression models, the modeling of curve data (for instance via GAMMs or FDA methods), and the use of Bayesian methods. This shift has been driven in part by the increased focus on large speech corpora in phonetics, which has been driven by machine learning methods such as forced alignment. We conclude by identifying opportunities for future research.

In this paper we determine the masses of $I(J^P)=0\left(3/2^+\right)$ and $0\left(3/2^-\right)$ $\Omega$-baryon ground states using lattice QCD. We utilise Wilson-clover ensembles with $2+1$ dynamical quark flavours generated by the CLS consortium along a trajectory with a constant trace of the quark-mass matrix. We show that N$^3$LO $\text{SU}(3)_f$ chiral perturbation theory expressions describe the ground-state masses with positive-parity well, and we use them to set the lattice scale. Methodologically, our combination of gauge-fixed wall sources and the generalized Pencil of Functions allows for high-precision determinations of the lattice spacing at a relative error of around $0.3\%$ with controlled excited-state contamination. The fit we perform allows for the continuum value of $t_0$ to vary, thereby determining this quantity with a comparable level of precision to that of the lattice scale. Using the resulting scales our measurement of the negative-parity $\Omega^{3/2^{-}}$ state is found to be consistent with the recently-discovered $\Omega(2012)^-$, which can therefore be assigned the quantum numbers $I(J^P)=0\left(3/2^-\right)$., Comment: 29 pages, 7 figures

The thermal photon emissivity at the QCD chiral crossover is investigated using imaginary momentum correlators. These have been measured on a newly generated $20 \times 96^3$ lattice-QCD ensemble with $\mathcal{O}(a)$-improved Wilson quarks and physical up, down and strange quark masses at a temperature $T=154$\,MeV near the pseudo-critical temperature. In order to realize the photon on-shell condition, the spatially transverse Euclidean correlators have to be evaluated at imaginary spatial momenta. Employing a bounding method, we present a preliminary result on the quantity $H_E(\omega_1)$, which corresponds to an energy-moment of the photon spectral function $\sigma(\omega)/\omega$ defined by the weight function $1/(\omega^2+\omega_n^2)$, the $\omega_n$ being integer multiples of $2\pi T$., Comment: 12 pages, 4 Figures, 1 Table

Following the publication of the new measurement of the anomalous magnetic moment of the muon, the discrepancy between experiment and the theory prediction from the $g-2$ theory initiative has increased to $4.2\,\sigma$. Recent lattice QCD calculations predict values for the hadronic vacuum polarization contribution that are larger than the data-driven estimates, bringing the Standard Model prediction closer to the experimental measurement. Euclidean time windows in the time-momentum representation of the hadronic vacuum polarization contribution to the muon $g-2$ can help clarify the discrepancy between the phenomenological and lattice predictions. We present our calculation of the intermediate distance window contribution using $N_\mathrm{f}=2+1$ flavors of O$(a)$ improved Wilson quarks. We employ ensembles at six lattice spacings below $0.1\,$fm and pion masses down to the physical value. We present a detailed study of the continuum limit, using two discretizations of the vector current and two independent sets of improvement coefficients. Our result at the physical point displays a tension of $3.9\,\sigma$ with a recent evaluation of the intermediate window based on the data-driven method., Comment: 10 pages, 5 figures, Proceedings of the 39th International Symposium on Lattice Field Theory, 8th-13th August 2022, Bonn, Germany

Hadronic light-by-light scattering is one of the virtual processes that causes the gyromagnetic factor $g$ of the muon to deviate from the value of two predicted by Dirac's theory. This process makes one of the largest contributions to the uncertainty of the Standard Model prediction for the muon $(g-2)$. Lattice QCD allows for a first-principles approach to computing this non-perturbative effect. In order to avoid power-law finite-size artifacts generated by virtual photons in lattice simulations, we follow a coordinate-space approach involving a weighted integral over the vertices of the QCD four-point function of the electromagnetic current carried by the quarks. Here we present in detail the semi-analytical calculation of the QED part of the amplitude, employing position-space perturbation theory in continuous, infinite four-dimensional Euclidean space. We also provide some useful information about a computer code for the numerical implementation of our approach that has been made public at https://github.com/RJHudspith/KQED., Comment: 84 pages, 13 figures; text matches the published version

Euclidean time windows in the integral representation of the hadronic vacuum polarization contribution to the muon $g-2$ serve to test the consistency of lattice calculations and may help in tracing the origins of a potential tension between lattice and data-driven evaluations. In this paper, we present results for the intermediate time window observable computed using O($a$) improved Wilson fermions at six values of the lattice spacings below 0.1\,fm and pion masses down to the physical value. Using two different sets of improvement coefficients in the definitions of the local and conserved vector currents, we perform a detailed scaling study which results in a fully controlled extrapolation to the continuum limit without any additional treatment of the data, except for the inclusion of finite-volume corrections. To determine the latter, we use a combination of the method of Hansen and Patella and the Meyer-Lellouch-L\"uscher procedure employing the Gounaris-Sakurai parameterization for the pion form factor. We correct our results for isospin-breaking effects via the perturbative expansion of QCD+QED around the isosymmetric theory. Our result at the physical point is $a_\mu^{\mathrm{win}}=(237.30\pm0.79_{\rm stat}\pm1.22_{\rm syst})\times10^{-10}$, where the systematic error includes an estimate of the uncertainty due to the quenched charm quark in our calculation. Our result displays a tension of 3.9$\sigma$ with a recent evaluation of $a_\mu^{\mathrm{win}}$ based on the data-driven method., Comment: 43 pages, 9 figures, 10 tables; version accepted for publication: extended discussion of finite-volume corrections. Results and conclusions unchanged

Linked Data (LD) as a web--based technology enables in principle the seamless, machine--supported integration, interplay and augmentation of all kinds of knowledge, into what has been labeled a huge knowledge graph. Despite decades of web technology and, more recently, the LD approach, the task to fully exploit these new technologies in the public domain is only commencing. One specific challenge is to transfer techniques developed preweb to order our knowledge into the realm of Linked Open Data (LOD) This paper illustrates two different models in which a general analytico--synthetic classification can be published and made available as LD. In both cases, an LD solution deals with the intricacies of a pre--coordinated indexing language.

We compute the hadronic light-by-light scattering contribution to the muon $g-2$ from the charm quark using lattice QCD. The calculation is performed on ensembles generated with dynamical $(u,d,s)$ quarks at the SU(3)$_{\rm f}$ symmetric point with degenerate pion and kaon masses of around 415 MeV. It includes the connected charm contribution, as well as the leading disconnected Wick contraction, involving the correlation between a charm and a light-quark loop. Cutoff effects turn out to be sizeable, which leads us to use lighter-than-physical charm masses, to employ a broad range of lattice spacings reaching down to 0.039 fm and to perform a combined charm-mass and continuum extrapolation. We use the $\eta_c$ meson to define the physical charm-mass point and obtain a final value of $a_\mu^{\rm HLbL,c} = (2.8\pm 0.5) \times 10^{-11}$, whose uncertainty is dominated by the systematics of the extrapolation. Our result is consistent with the estimate based on a simple charm-quark loop, whilst being free of any perturbative scheme dependence on the charm mass. The mixed charm-light disconnected contraction contributes a small negative amount to the final value., Comment: 21 pages, 8 figures, 9 tables

We present work designed to compute baryon masses on $N_f = 2 + 1$ CLS ensembles including isospin-breaking effects due to non-degenerate light quark masses and electromagnetic interactions. These effects are determined at leading order via a perturbative expansion around the iso-symmetric theory. We furthermore apply a group-theoretical operator construction for the various interpolators describing the different members of the baryon octet and decuplet based on a classification by spin, parity, and flavor content.

We compute the hadronic light-by-light scattering contribution to the muon $g-2$ from the up, down, and strange-quark sector directly using lattice QCD. Our calculation features evaluations of all possible Wick-contractions of the relevant hadronic four-point function and incorporates several different pion masses, volumes, and lattice-spacings. We obtain a value of $a_\mu^{\text{Hlbl}} = 106.8(14.7) \times 10^{-11}$ (adding statistical and systematic errors in quadrature), which is consistent with current phenomenological estimates and a previous lattice determination. It now appears conclusive that the hadronic light-by-light contribution cannot explain the current tension between theory and experiment for the muon $g-2$., Comment: 42 pages, 21 figures

We perform a lattice QCD calculation of the hadronic light-by-light contribution to $(g-2)_\mu$ at the SU(3) flavor-symmetric point $m_\pi=m_K\simeq 420\,$MeV. The representation used is based on coordinate-space perturbation theory, with all QED elements of the relevant Feynman diagrams implemented in continuum, infinite Euclidean space. As a consequence, the effect of using finite lattices to evaluate the QCD four-point function of the electromagnetic current is exponentially suppressed. Thanks to the SU(3)-flavor symmetry, only two topologies of diagrams contribute, the fully connected and the leading disconnected. We show the equivalence in the continuum limit of two methods of computing the connected contribution, and introduce a sparse-grid technique for computing the disconnected contribution. Thanks to our previous calculation of the pion transition form factor, we are able to correct for the residual finite-size effects and extend the tail of the integrand. We test our understanding of finite-size effects by using gauge ensembles differing only by their volume. After a continuum extrapolation based on four lattice spacings, we obtain $a_\mu^{\rm hlbl} = (65.4\pm 4.9 \pm 6.6)\times 10^{-11}$, where the first error results from the uncertainties on the individual gauge ensembles and the second is the systematic error of the continuum extrapolation. Finally, we estimate how this value will change as the light-quark masses are lowered to their physical values., Comment: 19 figures, 39 pages; improved references, in particular concerning the eta exchange; no figures or results changed

The measurement of the anomalous magnetic moment of the muon and its prediction allow for a high-precision test of the Standard Model (SM). In this proceedings article we present ongoing work combining lattice QCD and continuum QED in order to determine an important SM contribution to the magnetic moment, the hadronic light-by-light contribution. We compute the quark-connected contribution in the Mainz position-space approach and investigate the long-distance part of our data using calculations of the $\pi^0$-pole and charged pion loop contributions., Comment: 7 pages, 10 figures

To study the quantized Coulomb branch of 3d $\mathcal{N}=4$ unitary SQCD theories, we propose a new method to compute correlators of monopole and Casimir operators that are inserted in the $\mathbb{R}\times\mathbb{R}^2_\epsilon$ Omega background. This method combines results from supersymmetric localization with inputs from the brane realisation of the correlators in type IIB string theory. The main challenge is the computation of the partition functions of certain Super-Matrix-Models (SMMs), which appear in the contribution of monopole bubbling sectors and are realised as the theory living on the D1 strings in the brane construction. We find that the non-commutativity arising in the monopole operator insertions is related to a wall-crossing phenomenon in the FI parameter space of the SMM. We illustrate our method in various examples and we provide explicit results for arbitrary correlators of non-bubbling bare monopole operators. We also discuss the realisation of the non-commutative product as a Moyal (star) product and use it to successfully test our results., Comment: 71 pages + appendices, 16 figures. v2: typos corrected, references added, minor changes in section 4.2.1. v3: section 4.2 added, references added, to appear in JHEP

We present results from a calculation of beyond the standard model (BSM) kaon mixing including data physical with light quark masses. We simulate $N_f=2+1$ QCD with Iwasaki gauge and domain wall fermion action on 8 ensembles, spanning 3 lattice spacings and pion masses from the physical value up to 430MeV. The ratio of the BSM to standard model (SM) matrix elements are extracted from the correlation functions and renormalised using the RI-SMOM Rome-Southampton method with non-exceptional kinematics. The results at the physical point continuum limit are found by performing a simultaneous continuum chiral extrapolation. In this work we gain consistency with our previous results and achieve a reduction in both the statistical and systematic error., Comment: The 36th Annual International Symposium on Lattice Field

We continue our study of heavy-light four-quark states and find evidence from lattice QCD for the existence of a strong-interaction-stable $I(J^P)=0(1^+)$ $ud\bar{c}\bar{b}$ tetraquark with mass in the range of 15 to 61 MeV below $\bar{D}B^*$ threshold. Since this range includes the electromagnetic $\bar{D}B\gamma$ decay threshold, current uncertainties do not allow us to determine whether such a state would decay electromagnetically, or only weakly. We also perform a study at fixed pion mass, with NRQCD for the heavy quarks, simulating $qq^\prime \bar{b}^\prime \bar{b}$ and $q q^\prime \bar{b}^\prime\bar{b}^\prime$ tetraquarks with $q,\, q^\prime =ud$ or $\ell s$ and variable, unphysical $m_{b^\prime}$ in order to investigate the heavy mass-dependence of such tetraquark states. We find that the dependence of the binding energy follows a phenomenologically-expected form and that, though NRQCD breaks down before $m_{b^\prime}=m_c$ is reached, the results at higher $m_{b^\prime}$ clearly identify the $ud\bar{b}^\prime \bar{b}$ channel as the most likely to support a strong-interaction-stable tetraquark state at $m_{b^\prime}=m_c$. This observation serves to motivate the direct $ud\bar{c}\bar{b}$ simulation. Throughout we use dynamical $n_f=2+1$ ensembles with pion masses $m_\pi=$415, 299, and 164 MeV reaching down almost to the physical point, a relativistic heavy quark prescription for the charm quark, and NRQCD for the bottom quark(s)., Comment: 24 pages, 4 figures

As a simple model for dark matter, we propose a QCD-like theory based on $\rm{SU}(2)$ gauge theory with one flavor of dark quark. The model is confining at low energy and we use lattice simulations to investigate the properties of the lowest-lying hadrons. Compared to QCD, the theory has several peculiar differences: there are no Goldstone bosons or chiral symmetry restoration when the dark quark becomes massless; the usual global baryon number symmetry is enlarged to $\rm{SU}(2)_B$, resembling isospin; and baryons and mesons are unified together in $\rm{SU}(2)_B$ iso-multiplets. We argue that the lightest baryon, a vector boson, is a stable dark matter candidate and is a composite realization of the hidden vector dark matter scenario. The model naturally includes a lighter state, the analog of the $\eta^\prime$ in QCD, for dark matter to annihilate into to set the relic density via thermal freeze-out. Dark matter baryons may also be asymmetric, strongly self-interacting, or have their relic density set via $3 \to 2$ cannibalizing transitions. We discuss some experimental implications of coupling dark baryons to the Higgs portal., Comment: 26 pages, 16 figures

We present a determination of the QCD coupling constant, $\alpha_s$, obtained by fitting lattice results for the flavour $ud$ hadronic vacuum polarisation function to continuum perturbation theory. We use $n_f=2+1$ flavours of Domain Wall fermions generated by the RBC/UKQCD collaboration and three lattice spacings $a^{-1}=1.79,\, 2.38$ and $3.15\ \text{GeV}$. Several sources of potential systematic error are identified and dealt with. After fitting and removing expected leading cut-off effects, we find for the five-flavour $\overline{\text{MS}}$ coupling the value $\alpha_s(M_Z)=0.1181(27)^{+8}_{-22}$, where the first error is statistical and the second systematic.

We propose and apply a new approach to determining $|V_{us}|$ using dispersion relations with weight functions having poles at Euclidean (space-like) momentum which relate strange hadronic $\tau$ decay distributions to hadronic vacuum polarization functions (HVPs) obtained from lattice QCD. We show examples where spectral integral contributions from the region where experimental data have large errors or do not exist are strongly suppressed but accurate determinations of the relevant lattice HVP combinations remain possible. The resulting $|V_{us}|$ agrees well with determinations from $K$ physics and 3-family CKM unitarity. Advantages of this new approach over the conventional hadronic $\tau$ decay determination employing flavor-breaking sum rules are also discussed., Comment: 10 pages, 11 figures. References added and minor modifications. Accepted for publication in Physical Review Letters

We report on our progress in studying exotic, heavy tetraquark states, $qq\prime \bar Q\bar Q\prime$. Using publicly available dynamical $n_f =2+1$ Wilson-Clover gauge configurations, generated by the PACS-CS collaboration, with pion masses $\simeq$164, 299 and 415 MeV, we extend our previous analysis to heavy quark components containing heavier than physical bottom quarks $\bar Q\bar Q\prime=\bar b\prime\bar b\prime$ or $\bar Q\bar Q\prime=\bar b\bar b\prime$, charm and bottom quarks $\bar c\bar b$ and also only charm quarks $\bar c\bar c$. Throughout we employ NRQCD and relativistic heavy quarks for the heavier than bottom, bottom and charm quarks. Using our previously established diquark-antidiquark and meson-meson operator basis we comment in particular on the dependence of the binding energy on the mass of the heavy quark component $\bar Q\bar Q$, with heavy quarks ranging from $m_Q=0.85\ldots 6.3\cdot m_b$. In the heavy flavor non-degenerate case, $\bar Q\bar Q\prime$, and especially for the tetraquark channel $ud\bar c\bar b$, we extend our work to utilize a $3\times 3$ GEVP to study the ground and threshold states thereby enabling a clear identification of possible binding. Finally, we present initial work on the $\bar Q\bar Q\prime=\bar c\bar c$ system where a much larger operator basis is available in comparison to flavor combinations with NRQCD quarks., Comment: 8 pages, 5 figures, proceedings contribution to "Lattice 2017. 35th International Symposium on Lattice Field Theory", 18th-24th June 2017, Granada, Spain

We revisit the puzzle of $|V_{us}|$ values obtained from the conventional implementation of hadronic-$\tau$-decay-based flavor-breaking finite-energy sum rules lying $>3 \sigma$ below the expectations of three-family unitarity. Significant unphysical dependences of $|V_{us}|$ on the choice of weight, w, and upper limit, $s_0$, of the experimental spectral integrals entering the analysis are confirmed, and a breakdown of assumptions made in estimating higher dimension, $D>4$, OPE contributions is identified as the main source of these problems. A combination of continuum and lattice results is shown to suggest a new implementation of the flavor-breaking sum rule approach in which not only $|V_{us}|$, but also $D>4$ effective condensates, are fit to data. Lattice results are also used to clarify how to reliably treat the slowly converging D=2 OPE series. The new sum rule implementation is shown to cure the problems of the unphysical w- and $s_0$-dependence of $|V_{us}|$ and to produce results $\sim 0.0020$ higher than those of the conventional implementation. With B-factory input, and using, in addition, dispersively constrained results for the $K\pi$ branching fractions, we find $\vert V_{us}\vert =0.2231(27)_{exp}(4)_{th}$, in excellent agreement with the result from $K_{\ell 3}$, and compatible within errors with the expectations of three-family unitarity, thus resolving the long-standing inclusive $\tau$ $|V_{us}|$ puzzle., Comment: 15 pages, 4 figures. Updated treatment of strange hadronic tau decay data; expanded discussion of the breakdown of the conventional implementation approach. Final version to appear in Physics Letters B

SU(2) gauge theory with a single fermion in the fundamental representation is a minimal non-Abelian candidate for the dark matter sector, which is presently missing from the standard model. Having only a single flavor provides a natural mechanism for stabilizing dark matter on cosmological timescales. Preliminary lattice results are presented and discussed in the context of dark matter phenomenology., Comment: 7 pages, 5 figures, presented at the 34th International Symposium on Lattice Field Theory (Lattice 2016), 24-30 July 2016, Southampton, UK

We compute the hadronic matrix elements of the four-quark operators relevant for $K^0-{\bar K^0}$ mixing beyond the Standard Model. Our results are from lattice QCD simulations with $n_f=2+1$ flavours of domain-wall fermion, which exhibit continuum-like chiral-flavour symmetry. The simulations are performed at two different values of the lattice spacing ($a\sim0.08$ and $a\sim 0.11 \, \fm $) and with lightest unitary pion mass $\sim 300\, \MeV$. For the first time, the full set of relevant four-quark operators is renormalised non-perturbatively through RI-SMOM schemes; a detailed description of the renormalisation procedure is presented in a companion paper. We argue that the intermediate renormalisation scheme is responsible for the discrepancies found by different collaborations. We also study different normalisations and determine the matrix elements of the relevant four-quark operators with a precision of $\sim 5\%$ or better., Comment: 38 pages

We investigate the possibility of $qq^\prime \bar b \bar b$ tetraquark bound states using $n_f=2+1$ lattice QCD ensembles with pion masses $\simeq 164$, $299$, and $415$ MeV. Motivated by observations from heavy baryon phenomenology, we consider two lattice interpolating operators both of which are expected to couple efficiently to tetraquark states: one with diquark-antidiquark and one with a meson-meson structure. Using nonrelativistic QCD to simulate the bottom quarks, we study the $ud\bar b \bar b$, $\ell s\bar b \bar b$ channels with $\ell=u,d$, and find unambiguous signals for strong-interaction-stable $J^P=1^+$ tetraquarks. These states are found to lie $189(10)$ and $98(7)$ MeV below the corresponding free two-meson thresholds., Comment: 5 pages, 3 figures; published version

The QCD coupling appears in the perturbative expansion of the current-current two-point (vacuum polarization) function. Any lattice calculation of vacuum polarization is plagued by several competing non-perturbative effects at small momenta and by discretization errors at large momenta. We work in an intermediate region, computing the vacuum polarization for many off-axis momentum directions on the lattice. Having many momentum directions provides a way to monitor and account for lattice artifacts. Our results are competitive with, and have certain systematic advantages over, the alternate phenomenological determination of the strong coupling from the same light quark vacuum polarization produced by sum rule analyses of hadronic tau decay data., Comment: 7 pages, 4 figures, Proceedings of the 33rd International Symposium on Lattice Field Theory (Lattice 2015), 14-18 July 2015, Kobe International Conference Center, Kobe, Japan

We determined the NLO chiral low-energy constant $L_{10}$, and various combinations of NNLO chiral low-energy constants employing recently revised ALEPH results for the non-strange vector (V) and axial-vector (A) hadronic tau decay distributions and recently updated RBC/UKQCD lattice data for the non-strange V-A two-point function. In this talk, we explain the ingredients of this determination. Our errors are at or below the level expected for contributions of yet higher order in the chiral expansion, suggesting that our results exhaust the possibilities of what can be meaningfully achieved in an NNLO analysis., Comment: 6 pages, contribution to the proceedings of Chiral Dynamics 2015; reference corrected

We determine the NLO chiral low-energy constant $L_{10}^r$, and combinations $C_{12}^r\pm C_{61}^r+C_{80}^r$, $C_{13}^r-C_{62}^r+C_{81}^r$, $C_{61}^r$, and $C_{87}^r$, of the NNLO chiral low-energy constants incorporating recently revised ALEPH results for the non-strange vector ($V$) and axial-vector ($A$) hadronic $\tau$ decay distributions and recently updated RBC/UKQCD lattice data for the non-strange $V-A$ two-point function. In the $\bar{\rm MS}$ scheme, at renormalization scale $\mu=770\ {MeV}$, we find $L_{10}^r=-0.00350(17)$, $C_{12}^r+C_{61}^r+C_{80}^r=0.00237(16)\ {GeV}^{-2}$, $C_{12}^r-C_{61}^r+C_{80}^r=-0.00056(15)\ {GeV}^{-2}$, $C_{13}^r-C_{62}^r+C_{81}^r=0.00046(9)\ {GeV}^{-2}$, $C_{61}^r=0.00146(15)\ {GeV}^{-2}$, and $C_{87}^r=0.00510(22)\ {GeV}^{-2}$. With errors here at or below the level expected for contributions of yet higher order in the chiral expansion, the analysis exhausts the possibilities of what can be meaningfully achieved in an NNLO analysis. We also consider the dimension six and dimension eight coefficients in the operator product expansion in the $V-A$ channel., Comment: 16 pages, revtex

We report on our computation of the hadronic matrix elements of the four-quark operators needed for the study of $K^0-{\bar K^0}$ mixing beyond the Standard Model (SM). We consider nf=2+1 Domain-Wall fermions on Iwasaki gauge action with lightest unitary pion of 290 MeV and a single lattice spacing a=0.086 fm. The renormalization is performed non-perturbatively through the RI-MOM scheme and our results are converted perturbatively to MSbar. We have estimated the various systematic errors. Our results confirm a previous quenched study, where large ratios of non-SM to SM matrix elements were obtained., Comment: 7 pages, 3 figures. Contribution to the 30th International Symposium on Lattice Field Theory, June 24-29, 2012, Cairns, Australia

The Box Hill Learning Network (BHLN) in Australia has these two arenas of activity: to enable BHLN to become sustainable and to develop an online learning system that caters to the needs of the network. Partners are Box Hill Institute, Box Hill Hospital, Box Hill Senior Secondary, City of Manningham, and City of Whitehorse. Within this partnership, the BHLN aims to develop a community of practice; deliver work-based training through the use of online learning; and support the host communities as they develop strategies to become learning organizations. Establishment of BHLN has been a positive experience for the facilitators involved. There has been an imperative to create a community of practice before BHLN could begin to promote itself in other arenas. The attainment of this goal at such an early stage is significant. These activities or competencies to become a learning organization are to varying degrees becoming recognizable within BHLN's activities and work: scan and anticipate change in the environment; develop an ability to question, challenge, and change operational norms and assumptions; allow appropriate strategic directions and patterns of organizations to emerge; and become skilled in the art of double-loop learning. (YLB)

In 1991 the New Zealand Fire Service planned a primary school fire-safety education program for children from new entrants to form 2. The program introduces a new module to the children each year of their primary education. This study was undertaken in an attempt to measure the effectiveness of the program. A sample of 1,089 children completed questionnaires and a smaller sample of 100 pupils demonstrated their knowledge of fire-safety procedures, including stop, drop, and roll; crawl low in smoke; and phoning 111 (the emergency number). The 1995 results were compared with those gathered in 1992, prior to the introduction of the Fire Service's programs. It was assumed that any improvements in children's results could be attributed in large measure to the introduction of the programs, although it was also recognized that other factors could have intervened. The results of the 1992 questionnaire indicated that standard 2 children already had a high knowledge of fire-safety procedures prior to the introduction of the new fire-safety programs. Not much improvement was recorded in the 1995 data, though significantly more children indicated they would call the Fire Service first rather than a parent when they saw a fire, and significantly fewer children in 1995 knew the most appropriate procedure if they were in a room full of smoke. In the fire safety skills demonstrations, while more children showed a mastery of skills, results showed that children either knew exactly what to do or had no idea of the appropriate response. The findings of the study indicated that although standard 2 children in 1995 have a heightened awareness of fire-safety, there is still room for improvement and need for many more schools to participate in the program. The 1995 questionnaire is included in the appendix. (ND)

This study examined the experiences of students in the six New Zealand colleges of education who undertook a 3-year course of training to work in early childhood centers. The study aimed to find out students' expected employment following their training among child care, kindergarten, or other early childhood services, monitor any changes in the students' intentions during training, and establish the employment patterns of students in the first year after training. The students in the training were surveyed by the same questionnaire at the end of training year or at the first year of employment. The findings showed that while in the beginning of training the majority of students had preferred work places, 78 percent favored working in kindergartens when they had completed their preservice courses. Generally the training courses provide students with a wider range of services, and this encouraged students to think more positively about working in services other than kindergartens. Students appeared to be committed to work in early childhood and believed that their training prepared them well for their chosen profession. They were also appreciative of the opportunity provided for their own personal development, especially in the areas of human relations, communication skills, and awareness of equity issues. (AP)

This study examined kindergarten teachers' perceptions of the impact of changes in group-size policy on 3- and 4-year-old children in New Zealand's Wellington Region Free Kindergarten Association. Data were collected through a series of interviews of Wellington kindergarten teachers from 54 kindergartens and focused mainly on the perceived effects of changing group size with regard to parent-teacher relationships, staff and child turnover, and adult-child ratios. The findings show that the changed policy had had a direct impact on children, programmers, teachers, and families. The major issues presented by the teachers are as follows: (1) they had less time to work with individual children and small groups; (2) even though the adult-child ratio remained constant at 1:15, the larger group size had a marked impact on the type of activities teachers were able to offer; (3) teachers were being forced toward a supervisory role; (4) increased roll numbers had an adverse, diluting effect on teachers' relationships with parents; (5) in some kindergartens children were being admitted at a younger age, which placed extra demands on teachers; and (6) there had been little training or support for teachers to cope with the consequences of the new policy. (Two appendices include the kindergarten group size project questionnaire and the interview schedule. Contains 44 references.) (AP)

This study evaluated the implementation of the New Zealand Curriculum in primary schools, based on case studies of seven schools. The schools ranged in size from grade 1 up to and including Grade 5, and included schools in rural and urban areas and provincial towns. Data were collected through a series of semi-structured interviews with the principals, classroom teachers, and members of the schools' boards of trustees. Results indicated that the schools varied considerably in the progress they had made toward implementing the New Zealand Curriculum. The reasons contributing to this fact included: (1) the availability of staff development; (2) the leadership of the principal; (3) teacher attitude toward change; and (4) the amount of time needed to bring about change. However, one abiding impression from the interviews was the positive reaction of principals, teachers, and members of boards of trustees to the content of the curriculum statements. Many principals and teachers felt overloaded because of the number of curriculum documents with which they had to become familiar at a time when they were still coming to terms with structural changes within the education system along with never-ending social and other pressures. However, relatively few were critical of the content of the New Zealand Curriculum. (A copy of the Principals' Interview Schedule is appended.) Contains 47 references. (AA)

This study explored teacher perceptions of professional development in secondary schools in New Zealand, including the degree of teachers' involvement in, and satisfaction with, the professional development programs available to them and whether or not access to professional development is equitable. The survey of 181 teachers in New Zealand's Wellington and Manawatu/Wanganui regions revealed that 178 of them had participated in professional development activities during the previous 3 years. Courses taken were provided primarily by colleges of education, school-based programs, and subject associations. The courses addressed curriculum areas, assessment, counseling, teaching techniques, and management. The most common form of delivery was 1-day courses. More female than male teachers took four or more courses; overall, men were more likely to take fewer courses than women. Two-thirds of the teachers were satisfied with the quality of the courses attended. About half the teachers were satisfied with the amount of teacher development they had had, and half would have liked more. The most frequently mentioned barrier to teacher development was limited funding. Options for further research are noted, and the survey form is appended. (Contains 10 references.) (JDD)

A longitudinal study of teacher education in three New Zealand Colleges of Education (Auckland, Wellington, and Christchurch) was conducted between the years 1989-1992 to examine: (1) the process of teacher education as it unfolded over time for those involved in it; (2) the experiences of a cohort of students preparing to become primary school teachers; and (3) the professional socialization of teacher trainees. This final report of the project begins with an overview of the reactions of 100 beginning teachers to their experience in the classroom during their first year. It then shifts back in time to describe and discuss some of the findings related to the experiences of these beginning teachers and others in their cohort while they were students--their experiences of college courses which contributed to their current experiences as beginning teachers. The report brings together issues discussed with students and beginning teachers over the course of the four years, and sets the findings in a broader context. Informants' views raised questions about future policy, practice, and organization for teacher education in New Zealand. The document concludes with 4 student profiles. Contains approximately 150 references. (LL)

This document presents findings from the fourth and final phase of a longitudinal study of teacher education. The report is based on data collected in 1991 and 1992 from interviews with 100 beginning teachers trained at the Auckland, Wellington, and Christchurch Colleges of Education in New Zealand. The investigation focused on beginning teachers' experiences during their first year in the classroom; their perceptions of how they acquitted themselves as teachers, and their views on the effectiveness of teacher training. Following an introduction that deals with aims of the study, research objectives, and a summary of main findings based on data collected in 1991 and 1992, the report is organized into the following sections: methodology; graduates who did not get jobs; four-year students; beginning teachers; the first year of teaching; the value of the college program; the school and classroom experience; equity issues; the professional development of beginning teachers; and a discussion of issues that emerged. Approximately half the document consists of a series of beginning teacher profiles making extensive use of direct quotations. (LL)

This report examines the ways in which New Zealand's six colleges and schools of education have reacted to new responsibilities and challenges in producing better teachers and adapting to changed governmental requirements. It is based on interviews conducted with senior staff at the six institutions which are the main providers of teacher education in New Zealand. The report indicates that all the colleges are committed to degree programs as the norm for educating elementary teachers. All the colleges are acquiring contracts, primarily with the Ministry of Education, to develop curricula and implement teacher professional development programs. The colleges are investigating and piloting more flexible ways of delivering courses of preservice teacher education, including shortened courses and off-campus courses. Colleges are also recognizing the value of other types of educational experiences of students entering preservice teacher education programs. Colleges are using many approaches to improve the quality of practice teaching experiences. The colleges' increased autonomy is encouraging them, and a more competitive environment is forcing them, to pursue quality assurance goals more vigorously. (Contains 22 references.) (JDD)

This report presents findings from the third phase of a longitudinal study of teacher education, based on a survey of 289 students in their third and final year of training at Auckland, Wellington, and Christchurch Colleges of Education in New Zealand and interviews with 74 of the students. The study investigated students' perceptions of their third year of training (specifically their courses), students' perceptions of the curriculum areas they were involved with in their first year of teaching, key beliefs about education and learning, changes in student views between the beginning of training and entering the classroom, student performance and contributing factors, relationship with parents of students, attitudes toward teaching Maori, assessment of student teachers, college workload, and students' intentions. A series of six student profiles is provided in order to give a more rounded view of individual students. Major findings include, among others: (1) at the end of their training, almost all the students were confident about teaching and running an integrated curriculum program in their own classroom; (2) students were least looking forward to teaching Maori and music and using computers in the classroom; and (3) students were most looking forward to teaching reading, physical education, and written language--curriculum areas where they had most experience during training. (JDD)

The study reported in this document was conducted to measure the impact of the New Zealand Fire Service's new fire safety program on elementary school students. Firefighters in each fire station and voluntary fire brigade in New Zealand were responsible for arranging a visit to every elementary school within their area to present a learning module. The goal was to teach and demonstrate the use of three procedures: (1) phone 111 (to tell the Fire Service where the fire is); (2) crawl low in smoke (to escape from a room where there are smoke and fumes); and (3) stop, drop, and roll to extinguish the flames if clothing is on fire. A questionnaire was administered to a random sample of 1,014 children to establish their level of fire safety knowledge prior to the introduction of the lessons, and a survey was completed by the principal of each of 47 schools in the sample to find out if fire safety information had been included in the curriculum. It was found that standard (grade) 2 children possess a high level of knowledge of the three procedures of concern to the Fire Service, at least in terms of the questionnaire. It is noted that the high level of correct responses might be due to the forced choice type of questionnaire and that children must be able to demonstrate the correct response in an actual critical situation. From the principals' survey it was found that there had been an increase in Fire Service visits to schools and that fire safety was most often included in the health education curriculum. Copies of the questionnaires and a demonstration schedule are appended. (LL)

An appraisal was made of the policy implications of a commitment by the University of the West Indies (UWI) to develop distance education as an integral feature of its teaching responsibilities. Information was gathered through interviews with 163 educators and administrators at the 3 campuses of the University of the West Indies, its 8 member countries, and the University of the Virgin Islands. The study found that the proportion of students enrolled in distance education is expected to grow greatly by the year 2000, straining the resources of the university. Therefore, more faculty members and administrators are needed and technical equipment must be upgraded and increased in order to provide distance education. The study concluded that the university is becoming much more a dual-mode delivery system, with on-campus and distance education becoming more equal in importance and emphasis. The study recommended that the university should embark on a broad-based range of programs in four categories: (1) certificate, undergraduate, graduate, and diploma programs; (2) leadership programs drawing on research writings and experience distinctive of UWI and in the Caribbean; (3) noncredit programs of continuing education and professional updating; and (4) distance education programs for students undertaking sixth form or preliminary courses. (KC)

This study presents findings from the second phase of a longitudinal study of teacher education, based on interviews with 105 students in their second year of training at three colleges of education (Auckland, Wellington, and Christchurch) in New Zealand. The study investigated students' perceptions of their second year of training, their performance, and factors in student performance. Extensive use is made of direct quotations from students' interviews, and a series of student profiles is offered to give a more rounded view of individual students. Findings indicate that more than 80 percent of students were either as motivated or more motivated to be primary school teachers than when they began the course; students commented favorably on courses where there was a clear link between theory and practice and where the course was taught in a practical manner; students regarded their teaching practice experiences as the most valuable part of the course; and students' main concern about college assessment procedures was that assessment should assist their learning and give them a valid credential at the end of the course. Appendices report on those students who left college before completing their training, unsuccessful applicants to teacher training, reasons why students chose particular courses, college policies on assessment, and university courses taken by college students. (Contains 18 references.) (JDD)

Dryland ecosystems play an important role in determining how precipitation anomalies affect terrestrial carbonfluxes at regional to global scales. Thus, to understand how climate change may affect the global carbon cycle,we must also be able to understand and model its effects on dryland vegetation. Dynamic Global VegetationModels (DGVMs) are an important tool for modeling ecosystem dynamics, but they often struggle to reproduceseasonal patterns of plant productivity. Because the phenological niche of many plant species is linked to bothtotal productivity and competitive interactions with other plants, errors in how process-based models representphenology hinder our ability to predict climate change impacts. This may be particularly problematic in drylandecosystems where many species have developed a complex phenology in response to seasonal variability in bothmoisture and temperature. Here, we examine how uncertainty in key parameters as well as the structure ofexisting phenology routines affect the ability of a DGVM to match seasonal patterns of leaf area index (LAI) andgross primary productivity (GPP) across a temperature and precipitation gradient. First, we optimized modelparameters using a combination of site-level eddy covariance data and remotely-sensed LAI data. Second, wemodified the model to include a semi-deciduous phenology type and added flexibility to the representation ofgrass phenology. While optimizing parameters reduced model bias, the largest gains in model performance wereassociated with the development of our new representation of phenology. This modified model was able to bettercapture seasonal patterns of both leaf area index (R2=0.75) and gross primary productivity (R2=0.84), thoughits ability to estimate total annual GPP depended on using eddy covariance data for optimization. The new modelalso resulted in a more realistic outcome of modeled competition between grass and shrubs. These findingsdemonstrate the importance of improving how DGVMs represent phenology in order to accurately forecastclimate change impacts in dryland ecosystems.

Climate and disturbance alter forest dynamics, from individual trees to biomes and from years to millennia, leaving legacies that vary with local, meso and macroscales. Motivated by recent insights in temperate forests, we argue that temporal and spatial extents equivalent to that of the underlying drivers are necessary to characterize forest dynamics across scales. We focus specifically on characterizing mesoscale forest dynamics because they bridge fine‐scale (local) processes and the continental scale (macrosystems) in ways that are highly relevant for climate change science and ecosystem management. We revisit ecological concepts related to spatial and temporal scales and discuss approaches to gain a better understanding of climate–forest dynamics across scales.

Productivity of northern latitude forests is an important driver of the terrestrial carbon cycle and is already responding to climate change. Studies ofthe satellite-derived Normalized Difference VegetationIndex (NDVI) for northern latitudes indicate recent changes in plant productivity. These detected greening and browning trends are often attributedto a lengthening of the growing season from warming temperatures. Yet, disturbance-recovery dynamics are strong drivers of productivity and can mask direct effects of climate change. Here, we analyze 1-km resolution NDVI data from 1989to 2014 for the northern latitude forests of the Greater Yellowstone Ecosystem for changes in plant productivity to address the following questions:(1) To what degree has greening taken place in the GYE over the past three decades? and (2) What is the relative importance of disturbance and climate in explaining NDVI trends? We found that the spatial extents of statistically significant productivity trends were limited to local greening and browning areas. Disturbance history, predominately fire disturbance, was a major driver of these detected NDVI trends. After accounting for fire-,insect-, and human-caused disturbances, increasing productivity trends remained. Productivity of northern latitude forests is generally considered temperature-limited; yet, we found that precipitation was a key driver of greening in the GYE.