Incorporation of QCD Effects in Basic Corrections of the Electroweak Theory

We study the incorporation of QCD effects in the basic electroweak corrections \drcar, \drcarw, and \dr. They include perturbative \Ord{\alpha\alpha_s} contributions and $t\bar{t}$ threshold effects. The latter are studied in the resonance and Green-function approaches, in the framework of dispersion relations that automatically satisfy relevant Ward identities. Refinements in the treatment of the electroweak corrections, in both the \ms\ and the on-shell schemes of renormalization, are introduced, including the decoupling of the top quark in certain amplitudes, its effect on \hat{e}^2(\mz) and \sincarmz, the incorporation of recent results on the leading irreducible \Ord{\alpha^2} corrections, and simple expressions for the residual, i.e.\ ``non-electromagnetic'', parts of \drcar, \drcarw, and \dr. The results are used to obtain accurate values for \mw\ and \sincarmz, as functions of \mt\ and \mh. The higher-order effects induce shifts in these parameters comparable to the expected experimental accuracy, and they increase the prediction for \mt\ derived from current measurements. The \ms\ and the on-shell calculations of \dr, in a recently proposed formulation, are compared and found to be in excellent agreement over the wide ranges 60\GeV \leq \mh \leq 1 \TeV, \mz \leq \mt \leq 250 \GeV.Comment: 51 pages (needs doublespace, equations, and cite styles

Measurement of the plasma astrophysical S factor for the 3He(D, p)4He reaction in exploding molecular clusters

The plasma astrophysical S factor for the 3He(D, p)4He fusion reaction was measured for the first time at temperatures of few keV, using the interaction of intense ultrafast laser pulses with molecular deuterium clusters mixed with 3He atoms. Different proportions of D2 and 3He or CD4 and 3He were mixed in the gas jet target in order to allow the measurement of the cross-section for the 3He(D, p)4He reaction. The yield of 14.7 MeV protons from the 3He(D, p)4He reaction was measured in order to extract the astrophysical S factor at low energies. Our result is in agreement with other S factor parameterizations found in the literature

The Glueball Spectrum from a Potential Model

The spectrum of two-gluon glueballs below 3 GeV is investigated in a potential model with dynamical gluon mass using variational method. The short distance potential is approximated by one-gluon exchange, while the long distance part is taken as a breakable string. The mass and size of the radial as well as orbital excitations up to principle quantum number n=3 are evaluated. The predicted mass ratios are compared with experimental and lattice results.Comment: Revtex, 6 pages with 1 eps figur

EuroGammaS gamma characterisation system for ELI-NP-GBS: The nuclear resonance scattering technique

A Gamma Beam Characterisation System has been designed by the EuroGammaS association for thecommissioning and development of the Extreme Light Infrastructure-Nuclear Physics Gamma Beam System(ELI-NP-GBS) to be installed in Magurele, Romania. The characterisation system consists of four elements: aCompton spectrometer, a sampling calorimeter, a nuclear resonant scattering spectrometer (NRSS) and a beamprofile imager. In this paper, the nuclear resonant scattering spectrometer system, designed to perform anabsolute energy calibration for the gamma beam, will be describe

Comparing the use of ERA5 reanalysis dataset and ground-based agrometeorological data under different climates and topography in Italy

Study region: The study region is represented by seven irrigation districts distributed under different climate and topography conditions in Italy. Study focus: This study explores the reliability and consistency of the global ERA5 single levels and ERA5-Land reanalysis datasets in predicting the main agrometeorological estimates commonly used for crop water requirements calculation. In particular, the reanalysis data was compared, variable-by-variable (e.g., solar radiation, R-s; air temperature, T-air; relative humidity, RH; wind speed, u(10); reference evapotranspiration, ET0), with in situ agrometeorological obser-vations obtained from 66 automatic weather stations (2008-2020). In addition, the presence of a climate-dependency on their accuracy was assessed at the different irrigation districts. New hydrological insights for the region: A general good agreement was obtained between observed and reanalysis agrometeorological variables at both daily and seasonal scales. The best perfor-mance was obtained for T-air, followed by RH, R-s, and u(10) for both reanalysis datasets, especially under temperate climate conditions. These performances were translated into slightly higher accuracy of ET0 estimates by ERA5-Land product, confirming the potential of using reanalysis datasets as an alternative data source for retrieving the ET0 and overcoming the unavailability of observed agrometeorological data

Gauge-Independent W-Boson Partial Decay Widths

We calculate the partial decay widths of the W boson at one loop in the standard model using the on-shell renormalization scheme endowed with a gauge-independent definition of the Cabibbo-Kobayashi-Maskawa (CKM) mixing matrix. We work in $R_\xi$ gauge and explicitly verify that the final expressions are independent of the gauge parameters. Furthermore, we establish the relationship between the on-shell and $\bar{\mathrm{MS}}$ definitions of the CKM matrix, both in its generic form and in the Wolfenstein parameterization. As a by-product of our analysis, we recover the beta function of the CKM matrix.Comment: 15 pages; reference added; input parameters updated according to 2000 PDG report; accepted for publication in Phys. Rev.

Experimental study of fusion neutron and proton yields produced by petawatt-laser-irradiated D2-3He or CD4-3He clustering gases

We report on experiments in which the Texas Petawatt laser irradiated a mixture of deuterium or deuterated methane clusters and helium-3 gas, generating three types of nuclear fusion reactions: D(d, 3He)n, D(d, t)p and 3He(d, p)4He. We measured the yields of fusion neutrons and protons from these reactions and found them to agree with yields based on a simple cylindrical plasma model using known cross sections and measured plasma parameters. Within our measurement errors, the fusion products were isotropically distributed. Plasma temperatures, important for the cross sections, were determined by two independent methods: (1) deuterium ion time-of-flight, and (2) utilizing the ratio of neutron yield to proton yield from D(d, 3He)n and 3He(d, p)4He reactions, respectively. This experiment produced the highest ion temperature ever achieved with laser-irradiated deuterium clusters.Comment: 16 pages, 6 figure

Temperature measurements of fusion plasmas produced by petawatt laser-irradiated D2-3He or CD4-3He clustering gases

Two different methods have been employed to determine the plasma temperature in a laser-cluster fusion experiment on the Texas Petawatt laser. In the first, the temperature was derived from time-of-flight data of deuterium ions ejected from exploding D2 or CD4 clusters. In the second, the temperature was measured from the ratio of the rates of two different nuclear fusion reactions occurring in the plasma at the same time: D(d, 3He)n and 3He(d, p)4He. The temperatures determined by these two methods agree well, which indicates that: i) The ion energy distribution is not significantly distorted when ions travel in the disassembling plasma; ii) The kinetic energy of deuterium ions, especially the hottest part responsible for nuclear fusion, is well described by a near-Maxwellian distribution.Comment: 13 pages, 4 figure