Linear Transformation Method for Multinuclide Decay Calculation
Ding Yuan
2010-12-29
A linear transformation method for generic multinuclide decay calculations is presented together with its properties and implications. The method takes advantage of the linear form of the decay solution N(t) = F(t)N{sub 0}, where N(t) is a column vector that represents the numbers of atoms of the radioactive nuclides in the decay chain, N{sub 0} is the initial value vector of N(t), and F(t) is a lower triangular matrix whose time-dependent elements are independent of the initial values of the system.
Precision linear ramp function generator
Jatko, W.B.; McNeilly, D.R.; Thacker, L.H.
1984-08-01
A ramp function generator is provided which produces a precise linear ramp function which is repeatable and highly stable. A derivative feedback loop is used to stabilize the output of an integrator in the forward loop and control the ramp rate. The ramp may be started from a selected baseline voltage level and the desired ramp rate is selected by applying an appropriate constant voltage to the input of the integrator.
Precision linear ramp function generator
Jatko, W. Bruce (Knoxville, TN); McNeilly, David R. (Maryville, TN); Thacker, Louis H. (Knoxville, TN)
1986-01-01
A ramp function generator is provided which produces a precise linear ramp unction which is repeatable and highly stable. A derivative feedback loop is used to stabilize the output of an integrator in the forward loop and control the ramp rate. The ramp may be started from a selected baseline voltage level and the desired ramp rate is selected by applying an appropriate constant voltage to the input of the integrator.
Autocorrelation Function Statistics and Implication to Decay Ratio Estimation
March-Leuba, Jose A.
2016-01-01
This document summarizes the results of a series of computer simulations to attempt to identify the statistics of the autocorrelation function, and implications for decay ratio estimation.
Effective Yukawa couplings and flavor-changing Higgs boson decays at linear colliders
Gabrielli, E.; Mele, B.
2011-04-01
We analyze the advantages of a linear-collider program for testing a recent theoretical proposal where the Higgs boson Yukawa couplings are radiatively generated, keeping unchanged the standard-model mechanism for electroweak-gauge-symmetry breaking. Fermion masses arise at a large energy scale through an unknown mechanism, and the standard model at the electroweak scale is regarded as an effective field theory. In this scenario, Higgs boson decays into photons and electroweak gauge-boson pairs are considerably enhanced for a light Higgs boson, which makes a signal observation at the LHC straightforward. On the other hand, the clean environment of a linear collider is required to directly probe the radiative fermionic sector of the Higgs boson couplings. Also, we show that the flavor-changing Higgs boson decays are dramatically enhanced with respect to the standard model. In particular, we find a measurable branching ratio in the range (10{sup -4}-10{sup -3}) for the decay H{yields}bs for a Higgs boson lighter than 140 GeV, depending on the high-energy scale where Yukawa couplings vanish. We present a detailed analysis of the Higgs boson production cross sections at linear colliders for interesting decay signatures, as well as branching-ratio correlations for different flavor-conserving/nonconserving fermionic decays.
Neutrinoless double-beta decay in covariant density functional theory
Ring, P.; Yao, J. M.; Song, L. S.; Hagino, K.; Meng, J.
2015-10-15
We use covariant density functional theory beyond mean field in order to describe neutrinoless double-beta decay in a fully relativistic way. The dynamic effects of particle-number and angular-momentum conservations as well as shape fluctuations of quadrupole character are taken into account within the generator coordinate method for both initial and final nuclei. The calculations are based on the full relativistic transition operator. The nuclear matrix elements (NME’s) for a large number of possible transitions are investigated. The results are compared with various non-relativistic calculations, in particular also with the density functional theory based on the Gogny force. We find that the non-relativistic approximation is justified and that the total NME’s can be well approximated by the pure axial-vector coupling term. This corresponds to a considerable reduction of the computational effort.
Linear functional minimization for inverse modeling
Barajas-Solano, David A.; Wohlberg, Brendt Egon; Vesselinov, Velimir Valentinov; Tartakovsky, Daniel M.
2015-06-01
In this paper, we present a novel inverse modeling strategy to estimate spatially distributed parameters of nonlinear models. The maximum a posteriori (MAP) estimators of these parameters are based on a likelihood functional, which contains spatially discrete measurements of the system parameters and spatiotemporally discrete measurements of the transient system states. The piecewise continuity prior for the parameters is expressed via Total Variation (TV) regularization. The MAP estimator is computed by minimizing a nonquadratic objective equipped with the TV operator. We apply this inversion algorithm to estimate hydraulic conductivity of a synthetic confined aquifer from measurements of conductivity and hydraulic head. The synthetic conductivity field is composed of a low-conductivity heterogeneous intrusion into a high-conductivity heterogeneous medium. Our algorithm accurately reconstructs the location, orientation, and extent of the intrusion from the steady-state data only. Finally, addition of transient measurements of hydraulic head improves the parameter estimation, accurately reconstructing the conductivity field in the vicinity of observation locations.
{alpha}-decay hindrance factors: A probe of mean-field wave functions
Karlgren, D.; Liotta, R.J.; Wyss, R.; Huyse, M.; Vel, K. van de; Duppen, P. van
2006-06-15
A simple model to calculate {alpha}-decay hindrance factors (HF) with special emphasis on the shape coexistence in the Pb-Po region is presented. Using deformation values obtained from potential energy surface (PES) calculations as the only input, hindrance factors for the {alpha} decay of Rn and Po isotopes are calculated. The fair agreement between experimental and theoretical hindrance factors suggest that the wave function obtained from the energy minima of the PES calculations contains an important part of the correlations that play a role for the {alpha} decay. The model is applicable to shape coexistence in the Po and Pb region when minima are well defined. The calculated HF that emerge from these calculations render a different interpretation than the commonly assumed n-particle n-hole picture of the intruder states in the Pb region.
Energy Density Functional Study of Nuclear Matrix Elements for Neutrinoless {beta}{beta} Decay
Rodriguez, Tomas R. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64259 Darmstadt (Germany); Departamento de Fisica Teorica, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); CEA, Irfu, SPhN, Centre de Saclay, F-911191 Gif-sur-Yvette (France); Martinez-Pinedo, Gabriel [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64259 Darmstadt (Germany)
2010-12-17
We present an extensive study of nuclear matrix elements (NME) for the neutrinoless double-beta decay of the nuclei {sup 48}Ca, {sup 76}Ge, {sup 82}Se, {sup 96}Zr, {sup 100}Mo, {sup 116}Cd, {sup 124}Sn, {sup 128}Te, {sup 130}Te, {sup 136}Xe, and {sup 150}Nd based on state-of-the-art energy density functional methods using the Gogny D1S functional. Beyond-mean-field effects are included within the generating coordinate method with particle number and angular momentum projection for both initial and final ground states. We obtain a rather constant value for the NMEs around 4.7 with the exception of {sup 48}Ca and {sup 150}Nd, where smaller values are found. We analyze the role of deformation and pairing in the evaluation of the NME and present detailed results for the decay of {sup 150}Nd.
BenAbdallah, Abdallah; Hammami, Mohamed Ali; Kallel, Jalel
2009-03-05
In this paper we present some sufficient conditions for the robust stability and stabilization of time invariant uncertain piecewise linear system using homogenous piecewise polynomial Lyapunov function. The proposed conditions are given in terms of linear matrix inequalities which can be numerically solved. An application of the obtained result is given. It consists in resolving the stabilization of piecewise uncertain linear control systems by using a state piecewise linear feedback.
Determination of linear optics functions from TBT data
Alexahin, Y.; Gianfelice-Wendt, E.; /Fermilab
2006-05-01
A method for evaluation of coupled optics functions, detection of strong perturbing elements, determination of BPM calibration errors and tilts using turn-by-turn (TBT) data is presented as well as the new version of the Hamiltonian perturbation theory of betatron oscillations the method is based upon. An example of application of the considered method to the Tevatron is given.
Towards time-dependent current-density-functional theory in the non-linear regime
Escartn, J. M.; Vincendon, M.; Dinh, P. M.; Suraud, E.; Romaniello, P.; Reinhard, P.-G.
2015-02-28
Time-Dependent Density-Functional Theory (TDDFT) is a well-established theoretical approach to describe and understand irradiation processes in clusters and molecules. However, within the so-called adiabatic local density approximation (ALDA) to the exchange-correlation (xc) potential, TDDFT can show insufficiencies, particularly in violently dynamical processes. This is because within ALDA the xc potential is instantaneous and is a local functional of the density, which means that this approximation neglects memory effects and long-range effects. A way to go beyond ALDA is to use Time-Dependent Current-Density-Functional Theory (TDCDFT), in which the basic quantity is the current density rather than the density as in TDDFT. This has been shown to offer an adequate account of dissipation in the linear domain when the Vignale-Kohn (VK) functional is used. Here, we go beyond the linear regime and we explore this formulation in the time domain. In this case, the equations become very involved making the computation out of reach; we hence propose an approximation to the VK functional which allows us to calculate the dynamics in real time and at the same time to keep most of the physics described by the VK functional. We apply this formulation to the calculation of the time-dependent dipole moment of Ca, Mg and Na{sub 2}. Our results show trends similar to what was previously observed in model systems or within linear response. In the non-linear domain, our results show that relaxation times do not decrease with increasing deposited excitation energy, which sets some limitations to the practical use of TDCDFT in such a domain of excitations.
Long-range corrected density functional theory with linearly-scaled HF exchange
Song, Jong-Won; Hirao, Kimihiko
2015-12-31
Long-range corrected density functional theory (LC-DFT) attracts many chemists’ attentions as a quantum chemical method to be applied to large molecular system and its property calculations. However, the expensive time cost to evaluate the long-range HF exchange is a big obstacle to be overcome to be applied to the large molecular systems and the solid state materials. Upon this problem, we propose a linear-scaling method of the HF exchange integration, in particular, for the LC-DFT hybrid functional.
MULTIPASS MUON RLA RETURN ARCS BASED ON LINEAR COMBINED-FUNCTION MAGNETS
Vasiliy Morozov, Alex Bogacz, Yves Roblin, Kevin Beard
2011-09-01
Recirculating Linear Accelerators (RLA) are an efficient way of accelerating short-lived muons to the multi-GeV energies required for Neutrino Factories and TeV energies required for Muon Colliders. In this paper we present a design of a two-pass RLA return arc based on linear combined function magnets, in which both charge muons with momenta different by a factor of two are transported through the same string of magnets. The arc is composed of 60{sup o}-bending symmetric super cells allowing for a simple arc geometry closing. By adjusting the dipole and quadrupole components of the combined-function magnets, each super cell is designed to be achromatic and to have zero initial and final periodic orbit offsets for both muon momenta. Such a design provides a greater compactness than, for instance, an FFAG lattice with its regular alternating bends and is expected to possess a large dynamic aperture characteristic of linear-field lattices.
Luszczak, M.; Maciula, R.; Szczurek, A.
2009-02-01
We discuss production of nonphotonic electrons in proton-proton scattering at the relativistic heavy ion collider. The distributions in rapidity and transverse momentum of charm and bottom quarks/antiquarks are calculated in the k{sub t}-factorization approach. We use Kwiecinski unintegrated parton distributions and Ivanov-Nikolaev unintegrated gluon distribution. The hadronization of heavy quarks is done by means of Peterson and Braaten et al. fragmentation functions. The semileptonic decay functions are found by fitting recent semileptonic data obtained by the CLEO and BABAR collaborations. We get good description of the data at large transverse momenta of electrons and find a missing strength concentrated at small transverse momenta of electrons. Plausible missing mechanisms are discussed.
Schroeder, J. W. R. Skiff, F.; Howes, G. G.; Kletzing, C. A.; Carter, T. A.; Dorfman, S.
2015-12-10
Wave propagation can be an accurate method for determining material properties. High frequency whistler mode waves (0.7 < ω/|Ω{sub ce}| < 1) in an overdense plasma (ω{sub pe} > |Ω{sub ce}|) are damped primarily by Doppler-shifted electron cyclotron resonance. A kinetic description of whistler mode propagation parallel to the background magnetic field shows that damping is proportional to the parallel electron distribution function. This property enables an experimental determination of the parallel electron distribution function using a measurement of whistler mode wave absorption. The whistler mode wave absorption diagnostic uses this technique on UCLA’s Large Plasma Device (LaPD) to measure the distribution of high energy electrons (5 − 10v{sub te}) with 0.1% precision. The accuracy is limited by systematic effects that need to be considered carefully. Ongoing research uses this diagnostic to investigate the effect of inertial Alfvén waves on the electron distribution function. Results presented here verify experimentally the linear effects of inertial Alfvén waves on the reduced electron distribution function, a necessary step before nonlinear physics can be tested. Ongoing experiments with the whistler mode wave absorption diagnostic are making progress toward the first direct detection of electrons nonlinearly accelerated by inertial Alfvén waves, a process believed to play an important role in auroral generation.
Yanai, Takeshi; Fann, George I.; Beylkin, Gregory; Harrison, Robert J.
2015-02-25
Using the fully numerical method for time-dependent Hartree–Fock and density functional theory (TD-HF/DFT) with the Tamm–Dancoff (TD) approximation we use a multiresolution analysis (MRA) approach to present our findings. From a reformulation with effective use of the density matrix operator, we obtain a general form of the HF/DFT linear response equation in the first quantization formalism. It can be readily rewritten as an integral equation with the bound-state Helmholtz (BSH) kernel for the Green's function. The MRA implementation of the resultant equation permits excited state calculations without virtual orbitals. Moreover, the integral equation is efficiently and adaptively solved using amore » numerical multiresolution solver with multiwavelet bases. Our implementation of the TD-HF/DFT methods is applied for calculating the excitation energies of H2, Be, N2, H2O, and C2H4 molecules. The numerical errors of the calculated excitation energies converge in proportion to the residuals of the equation in the molecular orbitals and response functions. The energies of the excited states at a variety of length scales ranging from short-range valence excitations to long-range Rydberg-type ones are consistently accurate. It is shown that the multiresolution calculations yield the correct exponential asymptotic tails for the response functions, whereas those computed with Gaussian basis functions are too diffuse or decay too rapidly. Finally, we introduce a simple asymptotic correction to the local spin-density approximation (LSDA) so that in the TDDFT calculations, the excited states are correctly bound.« less
Least Squ Fit of Lin Combination of Exponential Decay
Energy Science and Technology Software Center (OSTI)
2001-07-06
This program fits by least squares a function which is a linear combination of real exponential decay functions. The function is y(k) = summation over j of a(j) * exp(-lambda(j) * k). Values of the independent variable (k) and the dependent variable y(k) are specified as input data. Weights may be specified as input information or set by the program (w(k) = 1/y(k) ).
Structure/Function Studies of Proteins Using Linear Scaling Quantum Mechanical Methodologies
Merz, K. M.
2004-07-19
We developed a linear-scaling semiempirical quantum mechanical (QM) program (DivCon). Using DivCon we can now routinely carry out calculations at the fully QM level on systems containing up to about 15 thousand atoms. We also implemented a Poisson-Boltzmann (PM) method into DivCon in order to compute solvation free energies and electrostatic properties of macromolecules in solution. This new suite of programs has allowed us to bring the power of quantum mechanics to bear on important biological problems associated with protein folding, drug design and enzyme catalysis. Hence, we have garnered insights into biological systems that have been heretofore impossible to obtain using classical simulation techniques.
Martin, V.; Egido, J.L.; Khoo, T.L.; Lauritsen, T.
1993-11-11
The electromagnetic decay of the nuclei {sup 152-154-156}Dy is analyzed using microscopic Hartree-Fock calculations at finite temperature. The theoretical collective transition probabilities are implemented in numerical simulations to produce theoretical espectra. Thermal shape fluctuations are also taken into account. The inclusion of these correlation is crucial in order to understand the main features of the collective E2 spectra of these isotopes at different energies. The theoretical calculations suggest a shape change as responsible for the unusual features of the spectrum of the nucleus {sup 154}Dy at high energy.
Snoek, Hella Leonie; /Vrije U., Amsterdam
2011-11-28
This thesis describes the measurement of the branching fractions of the suppressed charmed B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decays and the non-resonant B{sup 0} {yields} D{sup (*)-} {eta}{pi}{sup +} decays in approximately 230 million {Upsilon}(4S) {yields} B{bar B} events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10{sup -6}. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle {gamma}, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle {gamma} can be performed using the decays of neutral B mesons. The B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decay is sensitive to the angle {gamma} and, in comparison to the current decays that are being employed, could significantly enhance the
Miller, William; Liu, Jian; Miller, William H.
2008-03-15
The linearized approximation to the semiclassical initial value representation (LSC-IVR) is used to calculate time correlation functions relevant to the incoherent dynamic structure factor for inelastic neutron scattering from liquid para-hydrogen at 14 K. Various time correlations functions were used which, if evaluated exactly, would give identical results, but they do not because the LSC-IVR is approximate. Some of the correlation functions involve only linear operators, and others involve non-linear operators. The consistency of the results obtained with the various time correlation functions thus provides a useful test of the accuracy of the LSC-IVR approximation and its ability to treat correlation functions involving both linear and nonlinear operators in realistic anharmonic systems. The good agreement of the results obtained from different correlation functions, their excellent behavior in the spectral moment tests based on the exact moment constraints, and their semi-quantitative agreement with the inelastic neutron scattering experimental data all suggest that the LSC-IVR is indeed a good short-time approximation for quantum mechanical correlation functions.
Tussupbayev, Samat; Govind, Niranjan; Lopata, Kenneth A.; Cramer, Christopher J.
2015-03-10
We assess the performance of real-time time-dependent density functional theory (RT-TDDFT) for the calculation of absorption spectra of 12 organic dye molecules relevant to photovoltaics and dye sensitized solar cells with 8 exchange-correlation functionals (3 traditional, 3 global hybrids, and 2 range-separated hybrids). We compare the calculations with traditional linear-response (LR) TDDFT. In addition, we demonstrate the efficacy of the RT-TDDFT approach to calculate wide absorption spectra of two large chromophores relevant to photovoltaics and molecular switches.
Dunlap, B.I.; Brenner, D.W.; Mowrey, R.C.; Mintmire, J.W.; White, C.T. )
1990-05-15
Linear combination of Gaussian-type orbitals (LCGTO) --local-density-functional (LDF) cluster calculations give the interaction energy of two deuterium atoms in the interstices of titanium and palladium. Octahedral and tetrahedral interstices of the face-centered-cubic (fcc) lattice are modeled by six and four metal atoms, respectively. No short equilibrium separations, compared to the gas-phase equilibrium separation, are found even when expansion of the lattice and loading with additional deuterium and metal atoms are considered. The deuteron affinities of these clusters are in accord with the experimental site preference.
Suzuki, Mahiko
2005-05-13
We extend the perturbative argument of helicity amplitudes to the two-body baryonic decays of B decays.
Zuehlsdorff, T. J. Payne, M. C.; Hine, N. D. M.; Haynes, P. D.
2015-11-28
We present a solution of the full time-dependent density-functional theory (TDDFT) eigenvalue equation in the linear response formalism exhibiting a linear-scaling computational complexity with system size, without relying on the simplifying Tamm-Dancoff approximation (TDA). The implementation relies on representing the occupied and unoccupied subspaces with two different sets of in situ optimised localised functions, yielding a very compact and efficient representation of the transition density matrix of the excitation with the accuracy associated with a systematic basis set. The TDDFT eigenvalue equation is solved using a preconditioned conjugate gradient algorithm that is very memory-efficient. The algorithm is validated on a small test molecule and a good agreement with results obtained from standard quantum chemistry packages is found, with the preconditioner yielding a significant improvement in convergence rates. The method developed in this work is then used to reproduce experimental results of the absorption spectrum of bacteriochlorophyll in an organic solvent, where it is demonstrated that the TDA fails to reproduce the main features of the low energy spectrum, while the full TDDFT equation yields results in good qualitative agreement with experimental data. Furthermore, the need for explicitly including parts of the solvent into the TDDFT calculations is highlighted, making the treatment of large system sizes necessary that are well within reach of the capabilities of the algorithm introduced here. Finally, the linear-scaling properties of the algorithm are demonstrated by computing the lowest excitation energy of bacteriochlorophyll in solution. The largest systems considered in this work are of the same order of magnitude as a variety of widely studied pigment-protein complexes, opening up the possibility of studying their properties without having to resort to any semiclassical approximations to parts of the protein environment.
Christofilos, N.C.; Polk, I.J.
1959-02-17
Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.
Martin, V.; Egido, J.L.; Khoo, T.L.; Lauritsen, T.
1995-06-01
The electromagnetic decay of the nuclei {sup 152,154,156}Dy is analyzed using microscopic Hartree-Fock calculations at finite temperature. The theoretical collective transition probabilities are implemented in numerical simulations to produce theoretical spectra. Thermal shape fluctuations are also taken into account. The inclusion of these correlation is crucial in order to understand the main features of the collective {ital E}2 spectra of these isotopes at different energies. The theoretical calculations suggest a shape change as responsible for the unusual features of the spectrum of the nucleus {sup 154}Dy at high energy.
Blais, AR; Dekaban, M; Lee, T-Y
2014-08-15
Quantitative analysis of dynamic positron emission tomography (PET) data usually involves minimizing a cost function with nonlinear regression, wherein the choice of starting parameter values and the presence of local minima affect the bias and variability of the estimated kinetic parameters. These nonlinear methods can also require lengthy computation time, making them unsuitable for use in clinical settings. Kinetic modeling of PET aims to estimate the rate parameter k{sub 3}, which is the binding affinity of the tracer to a biological process of interest and is highly susceptible to noise inherent in PET image acquisition. We have developed linearized kinetic models for kinetic analysis of dynamic contrast enhanced computed tomography (DCE-CT)/PET imaging, including a 2-compartment model for DCE-CT and a 3-compartment model for PET. Use of kinetic parameters estimated from DCE-CT can stabilize the kinetic analysis of dynamic PET data, allowing for more robust estimation of k{sub 3}. Furthermore, these linearized models are solved with a non-negative least squares algorithm and together they provide other advantages including: 1) only one possible solution and they do not require a choice of starting parameter values, 2) parameter estimates are comparable in accuracy to those from nonlinear models, 3) significantly reduced computational time. Our simulated data show that when blood volume and permeability are estimated with DCE-CT, the bias of k{sub 3} estimation with our linearized model is 1.97 ± 38.5% for 1,000 runs with a signal-to-noise ratio of 10. In summary, we have developed a computationally efficient technique for accurate estimation of k{sub 3} from noisy dynamic PET data.
Apitz, D.; Bertram, R.P.; Benter, N.; Buse, K.; Hieringer, W.; Andreasen, J.W.; Nielsen, M.M.; Johansen, P.M.
2005-09-01
Free-beam interferometry and angle-resolved absorption spectra are used to investigate the linear electro-optic coefficients and the linear dichroism in photoaddressable bis-azo copolymer thin films. From the first- and second order parameters deduced, the chromophore orientation distribution is calculated and displayed for several poling temperatures and chromophore concentrations. The influence of dipole-dipole interaction on the overall polymer dynamics is discussed. The first order parameter, and therefore the Pockels effect, peaks for a poling temperature of around 10 deg. C above the glass transition. The decrease of the Pockels effect above this temperature region is triggered by a head-to-tail chromophore orientation, i.e., a transition to a microcrystalline phase, increasing the second order parameter. Comparison of the experimentally observed absorption spectra and those obtained by density-functional calculations support the picture of differently aligned bis-azo dye molecules in a trans,trans configuration. Complementary wide-angle x-ray scattering is recorded to confirm the various kinds of ordering in samples poled at different temperatures.
U.S. Department of Energy (DOE) all webpages (Extended Search)
Linear Accelerator (LINAC) The core of the LANSCE facility is one of the nation's most powerful proton linear accelerators or LINAC. The LINAC at LANSCE has served the nation since 1972, providing the beam current required by all the experimental areas that support NNSA-DP and other DOE missions. The LINAC's capability to reliably deliver beam current is the key to the LANSCE's ability to do research-and thus the key to meeting NNSA and DOE mission deliverables. The LANSCE Accelerator The LANSCE
Emma, P.
1995-06-01
The Stanford Linear Collider (SLC) is the first and only high-energy e{sup +}e{sup {minus}} linear collider in the world. Its most remarkable features are high intensity, submicron sized, polarized (e{sup {minus}}) beams at a single interaction point. The main challenges posed by these unique characteristics include machine-wide emittance preservation, consistent high intensity operation, polarized electron production and transport, and the achievement of a high degree of beam stability on all time scales. In addition to serving as an important machine for the study of Z{sup 0} boson production and decay using polarized beams, the SLC is also an indispensable source of hands-on experience for future linear colliders. Each new year of operation has been highlighted with a marked improvement in performance. The most significant improvements for the 1994-95 run include new low impedance vacuum chambers for the damping rings, an upgrade to the optics and diagnostics of the final focus systems, and a higher degree of polarization from the electron source. As a result, the average luminosity has nearly doubled over the previous year with peaks approaching 10{sup 30} cm{sup {minus}2}s{sup {minus}1} and an 80% electron polarization at the interaction point. These developments as well as the remaining identifiable performance limitations will be discussed.
Colgate, S.A.
1958-05-27
An improvement is presented in linear accelerators for charged particles with respect to the stable focusing of the particle beam. The improvement consists of providing a radial electric field transverse to the accelerating electric fields and angularly introducing the beam of particles in the field. The results of the foregoing is to achieve a beam which spirals about the axis of the acceleration path. The combination of the electric fields and angular motion of the particles cooperate to provide a stable and focused particle beam.
Minezawa, Noriyuki
2014-10-28
Examining photochemical processes in solution requires understanding the solvent effects on the potential energy profiles near conical intersections (CIs). For that purpose, the CI point in solution is determined as the crossing between nonequilibrium free energy surfaces. In this work, the nonequilibrium free energy is described using the combined method of linear-response free energy and collinear spin-flip time-dependent density functional theory. The proposed approach reveals the solvent effects on the CI geometries of stilbene in an acetonitrile solution and those of thymine in water. Polar acetonitrile decreases the energy difference between the twisted minimum and twisted-pyramidalized CI of stilbene. For thymine in water, the hydrogen bond formation stabilizes significantly the CI puckered at the carbonyl carbon atom. The result is consistent with the recent simulation showing that the reaction path via this geometry is open in water. Therefore, the present method is a promising way of identifying the free-energy crossing points that play an essential role in photochemistry of solvated molecules.
Henry, J.J.
1961-09-01
A linear count-rate meter is designed to provide a highly linear output while receiving counting rates from one cycle per second to 100,000 cycles per second. Input pulses enter a linear discriminator and then are fed to a trigger circuit which produces positive pulses of uniform width and amplitude. The trigger circuit is connected to a one-shot multivibrator. The multivibrator output pulses have a selected width. Feedback means are provided for preventing transistor saturation in the multivibrator which improves the rise and decay times of the output pulses. The multivibrator is connected to a diode-switched, constant current metering circuit. A selected constant current is switched to an averaging circuit for each pulse received, and for a time determined by the received pulse width. The average output meter current is proportional to the product of the counting rate, the constant current, and the multivibrator output pulse width.
On the neutrinoless double ?{sup +}/EC decays
Suhonen, Jouni
2013-12-30
The neutrinoless double positron-emission/electron-capture (0??{sup +}/EC) decays are studied for the magnitudes of the involved nuclear matrix elements (NMEs). Decays to the ground state, 0{sub gs}{sup +}, and excited 0{sup +} states are discussed. The participant many-body wave functions are evaluated in the framework of the quasiparticle random-phase approximation (QRPA). Effective, G-matrix-derived nuclear forces are used in realistic single-particle model spaces. The channels ?{sup +}?{sup +}, ?{sup +}EC, and the resonant neutrinoless double electron capture (R0?ECEC) are discussed.
Correlations and the neutrinoless double beta decay
Menendez, J.; Poves, A. [Departamento de Fisica Teorica, and IFT, UAM-CSIC, Universidad Autonoma de Madrid, 28049-Madrid (Spain); Caurier, E.; Nowacki, F. [IPHC, IN2P3-CNRS/Universite Louis Pasteur, 67037-Strasbourg (France)
2009-11-09
We explore the influence of the deformation on the nuclear matrix elements of the neutrinoless double beta decay (NME), concluding that the difference in deformation -or more generally on the amount of quadrupole correlations- between parent and grand daughter nuclei quenchs strongly the decay. We discuss how varies the nuclear matrix element of {sup 76}Ge decay when the wave functions of the two nuclei involved in the transition are constrained to reproduce the experimental occupancies. In the Interacting Shell Model description the value of the NME is enhanced about 15% compared to previous calculations, whereas in the QRPA the NME's are reduced by 20%-30%, thus, the discrepancies between both approaches diminish.
B Decays Involving Light Mesons
Eschrich, Ivo Gough; /UC, Irvine
2007-01-09
Recent BABAR results for decays of B-mesons to combinations of non-charm mesons are presented. This includes B decays to two vector mesons, B {yields} {eta}{prime}({pi}, K, {rho}) modes, and a comprehensive Dalitz Plot analysis of B {yields} KKK decays.
Kaxiras, Efthimios; Moniz, Ernest J.; Soyeur, Madeleine
1985-08-01
The radiative decay widths of the low-lying strange baryons are calculated both within the relativistic quark bag model and the nonrelativistic potential model. These widths are found to depend sensitively upon the quark-model dynamics through multiplet mixing and q^{4}q-bar admixtures. The comparison between our calculated results and the very limited experimental data is discussed.
Nanal, Vandana [Dept. of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Mumbai 400 005 (India)
2011-11-23
At present, neutrinoless double beta decay is perhaps the only experiment that can tell us whether the neutrino is a Dirac or a Majorana particle. Given the significance of the 0{nu}{beta}{beta}, there is a widespread interest for these rare event studies employing a variety of novel techniques. This paper describes the current status of DBD experiments. The Indian effort for an underground NDBD experiment at the upcoming INO laboratory is also presented.
U.S. Department of Energy (DOE) all webpages (Extended Search)
Double Beta Decay Measuring the Mass of the Neutrino One of the most elusive and exotic subatomic particles being investigated around the world today is the neutrino. Understanding the family of neutrino particles and how they interact with other matter (and among themselves) has become one the most intensive physics research efforts ever attempted by mankind. With a virtually undetectable mass, and without electric charge, these weakly interacting particles have been devilishly difficult to
Kocher, D.C.
1981-01-01
The estimation of radiation dose to man from either external or internal exposure to radionuclides requires a knowledge of the energies and intensities of the atomic and nuclear radiations emitted during the radioactive decay process. The availability of evaluated decay data for the large number of radionuclides of interest is thus of fundamental importance for radiation dosimetry. This handbook contains a compilation of decay data for approximately 500 radionuclides. These data constitute an evaluated data file constructed for use in the radiological assessment activities of the Technology Assessments Section of the Health and Safety Research Division at Oak Ridge National Laboratory. The radionuclides selected for this handbook include those occurring naturally in the environment, those of potential importance in routine or accidental releases from the nuclear fuel cycle, those of current interest in nuclear medicine and fusion reactor technology, and some of those of interest to Committee 2 of the International Commission on Radiological Protection for the estimation of annual limits on intake via inhalation and ingestion for occupationally exposed individuals.
Jackson, P.D.; /Victoria U.
2006-02-24
Recent results from Belle and BaBar on rare B decays involving flavor-changing neutral currents or purely leptonic final states are presented. Measurements of the CP asymmetries in B {yields} K*{gamma} and b {yields} s{gamma} are reported. Also reported are updated limits on B{sup +} {yields} K{sup +}{nu}{bar {nu}}, B{sup +} {yields} {tau}{sup +}{nu}, B{sup +} {yields} {mu}{sup +}{nu} and the recent measurement of B {yields} X{sub s}{ell}{sup +}{ell}{sup -}.
Hall, L.J.
1986-08-29
The stability of the lightest superpartner is a crucial aspect of many experimental searches for supersymmetry and of supersymmetric dark matter candidates. It is shown that R parity may occur in operators of dimension four or less as an accidental consequence of an exact Z/sub N/ symmetry. In this case the lightest superpartner can decay via higher dimension operators. The lifetime depends on the scale of the new physics responsible for the non-renormalizable operators; it could be anywhere in the region 10/sup -20/ seconds to 10/sup +20/ seconds. Explicit examples are given. 12 refs.
Plasma wave aided two photon decay of an electromagnetic wave in a plasma
Kumar, K. K. Magesh; Singh, Rohtash; Krishan, Vinod
2014-11-15
The presence of a Langmuir wave in an unmagnetized plasma is shown to allow parametric decay of an electromagnetic wave into two electromagnetic waves, which is otherwise not allowed due to wave number mismatch. The decay occurs at plasma densities below one ninth the critical density and the decay waves propagate at finite angles to the pump laser. Above the threshold, the growth rate scales linearly with the amplitude of the Langmuir wave and the amplitude of the pump electromagnetic wave. The frequency ω of the lower frequency decay wave increases with the angle its propagation vector makes with that of the pump. The growth rate, however, decreases with ω.
Lattice calculation of nonleptonic charm decays
Simone, J.N.
1991-11-01
The decays of charmed mesons into two body nonleptonic final states are investigated. Weak interaction amplitudes of interest in these decays are extracted from lattice four-point correlation functions using a effective weak Hamiltonian including effects to order G{sub f} in the weak interactions yet containing effects to all orders in the strong interactions. The lattice calculation allows a quantitative examination of non-spectator processes in charm decays helping to elucidate the role of effects such as color coherence, final state interactions and the importance of the so called weak annihilation process. For D {yields} K{pi}, we find that the non-spectator weak annihilation diagram is not small, and we interpret this as evidence for large final state interactions. Moreover, there is indications of a resonance in the isospin {1/2} channel to which the weak annihilation process contributes exclusively. Findings from the lattice calculation are compared to results from the continuum vacuum saturation approximation and amplitudes are examined within the framework of the 1/N expansion. Factorization and the vacuum saturation approximation are tested for lattice amplitudes by comparing amplitudes extracted from lattice four-point functions with the same amplitude extracted from products of two-point and three-point lattice correlation functions arising out of factorization and vacuum saturation.
A Search for Neutrinoless Tau Decays to Three Leptons
Kolb, Jeffrey A.; /Oregon U. /SLAC; ,
2008-09-24
Using approximately 350 million {tau}{sup +}{tau}{sup -} pair events recorded with the BaBar detector at the Stanford Linear Accelerator Center between 1999 and 2006, a search has been made for neutrinoless, lepton-flavor violating tau decays to three lighter leptons. All six decay modes consistent with conservation of electric charge and energy have been considered. With signal selection efficiencies of 5-12%, we obtain 90% confidence level upper limits on the branching fraction {Beta}({tau} {yields} {ell}{ell}{ell}) in the range (4-8) x 10{sup -8}.
Soudan 2 nucleon decay experiment
Thron, J.L.
1986-01-01
The Soudan 2 nucleon decay experiment consists of a 1.1 Kton fine grained iron tracking calorimeter. It has a very isotropic detection structure which along with its flexible trigger will allow detection of multiparticle and neutrino proton decay modes. The detector has now entered its construction stage.
Gaitan, R.; Miranda, O. G.; Cabral-Rosetti, L. G.
2009-04-20
Top quark decays are interesting as a mean to test the Standard Model (SM) predictions. The Cabbibo-Kobayashi-Maskawa (CKM)-suppressed process t{yields}cWW, and the rare decays t{yields}cZ, t{yields}H{sup 0}+c, and t{yields}c{gamma} an excellent window to probe the predictions of theories beyond the SM. We evaluate the flavor changing neutral currents (FCNC) decay t{yields}H{sup 0}+c in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions; the FCNC decays may place at tree level and are only supressed by the mixing between ordinary top and charm quarks. We also comment on the decay process t{yields}c+{gamma}, which involves radiative corrections.
{tau} decays and chiral perturbation theory
Colangelo, G.; Finkemeier, M.; Urech, R.
1996-10-01
In a small window of phase space, chiral perturbation theory can be used to make standard model predictions for {tau} decays into two and three pions. For {tau}{r_arrow}2{pi}{nu}{sub {tau}}, we give the analytical result for the relevant form factor {ital F}{sub {ital V}} up to two loops, then calculate the differential spectrum and compare with available data. For {tau}{r_arrow}3{pi}{nu}{sub {tau}}, we have calculated the hadronic matrix element to one loop. We discuss the decomposition of the three pion states into partition states and we give detailed predictions for the decay in terms of structure functions. We also compare with low energy predictions of meson dominance models. Overall, we find good agreement, but also some interesting discrepancies, which might have consequences beyond the limit of validity of chiral perturbation theory. {copyright} {ital 1996 The American Physical Society.}
DOSIMETRY; RADIOISOTOPES; DECAY; ACCURACY; DATA COMPILATION;...
Office of Scientific and Technical Information (OSTI)
Radioactive decay data tables Kocher, D.C. 61 RADIATION PROTECTION AND DOSIMETRY; RADIOISOTOPES; DECAY; ACCURACY; DATA COMPILATION; DOSIMETRY; M CODES; COMPUTER CODES; DATA;...
Moretto, L.G.; Wozniak, G.J.
1988-11-01
The formation of hot compound nuclei in intermediate-energy heavy ion reactions is discussed. The statistical decay of such compound nuclei is responsible for the abundant emission of complex fragments and high energy gamma rays. 43 refs., 23 figs.
CP Violation in Tau to K* Decays
Hodgkinson, Mark; /Manchester U.
2006-03-10
A sample of {tau}{sup {+-}} {yields} K*{sup {+-}} decays with K*{sup {+-}} {yields} K{sub S}{sup 0}{pi}{sup {+-}} and K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}, using 123.4 fb{sup -1} of data collected by the BaBar detector at the Stanford Linear Accelerator Center, is used to search for a direct CP violation effect in the charged Higgs sector. No evidence of CP violation is found and the imaginary part of the charged Higgs coupling, {l_brace}Im{r_brace}({Lambda}), in the Multi-Higgs-Doublet-Model is found to be at -0.284 < {l_brace}Im{r_brace}({Lambda}) < 0.200 at 90% Confidence Level. In addition the installation of the kk2f Monte Carlo generator into the BaBar software framework is described.
Fault tolerant linear actuator
Tesar, Delbert
2004-09-14
In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.
Linear phase compressive filter
McEwan, Thomas E.
1995-01-01
A phase linear filter for soliton suppression is in the form of a laddered series of stages of non-commensurate low pass filters with each low pass filter having a series coupled inductance (L) and a reverse biased, voltage dependent varactor diode, to ground which acts as a variable capacitance (C). L and C values are set to levels which correspond to a linear or conventional phase linear filter. Inductance is mapped directly from that of an equivalent nonlinear transmission line and capacitance is mapped from the linear case using a large signal equivalent of a nonlinear transmission line.
Linear phase compressive filter
McEwan, T.E.
1995-06-06
A phase linear filter for soliton suppression is in the form of a laddered series of stages of non-commensurate low pass filters with each low pass filter having a series coupled inductance (L) and a reverse biased, voltage dependent varactor diode, to ground which acts as a variable capacitance (C). L and C values are set to levels which correspond to a linear or conventional phase linear filter. Inductance is mapped directly from that of an equivalent nonlinear transmission line and capacitance is mapped from the linear case using a large signal equivalent of a nonlinear transmission line. 2 figs.
Snapshot: Linear Lamps (TLEDs)
A report using LED Lighting Facts data to examine the current state of the market for linear fluorescent lamps. (8 pages, July 2016)
Focusing in Linear Accelerators
DOE R&D Accomplishments [OSTI]
McMillan, E. M.
1950-08-24
Review of the theory of focusing in linear accelerators with comments on the incompatibility of phase stability and first-order focusing in a simple accelerator.
Parametric instability of a monochromatic Alfven wave: Perpendicular decay in low beta plasma
Gao, Xinliang; Lu, Quanming; Shan, Lican; Wang, Shui; Li, Xing
2013-07-15
Two-dimensional hybrid simulations are performed to investigate the parametric decay of a monochromatic Alfven wave in low beta plasma. Both the linearly and left-hand polarized pump Alfven waves are considered in the paper. For the linearly polarized pump Alfven wave, either a parallel or obliquely propagating wave can lead to the decay along the perpendicular direction. Initially, the parametric decay takes place along the propagating direction of the pump wave, and then the decay occurs in the perpendicular direction. With the increase of the amplitude and the propagating angle of the pump wave (the angle between the propagating direction of the pump wave and the ambient magnetic field), the spectral range of the excited waves becomes broad in the perpendicular direction. But the effects of the plasma beta on the spectral range of the excited waves in perpendicular direction are negligible. However, for the left-hand polarized pump Alfven wave, when the pump wave propagates along the ambient magnetic field, the parametric decay occurs nearly along the ambient magnetic field, and there is no obvious decay in the perpendicular direction. Significant decay in the perpendicular direction can only be found when the pump wave propagates obliquely.
Linearly polarized fiber amplifier
Kliner, Dahv A.; Koplow, Jeffery P.
2004-11-30
Optically pumped rare-earth-doped polarizing fibers exhibit significantly higher gain for one linear polarization state than for the orthogonal state. Such a fiber can be used to construct a single-polarization fiber laser, amplifier, or amplified-spontaneous-emission (ASE) source without the need for additional optical components to obtain stable, linearly polarized operation.
Farrington, Sinead M.; /Liverpool U.
2006-10-01
The confidence level limits of the CDF search for the B{sub s}{sup 0} and B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -} rare decays and the branching ratio measurement of B{sub s}{sup 0} {yields} D{sub s}{sup +} D{sub s}{sup -} are presented.
A proposed Regulatory Guide basis for spent fuel decay heat
Hermann, O.W.; Parks, C.V.; Renier, J.P.
1991-01-01
A proposed revision to Regulatory Guide 3.54, Spent Fuel Heat Generation in an Independent Spent Fuel Storage Installation'' has been developed for the US Nuclear Regulatory Commission. The proposed revision includes a data base of decay heat rates calculated as a function of burnup, specific power, cooling time, initial fuel {sup 235}U enrichment and assembly type (i.e., PWR or BWR). Validation of the calculational method was done by comparison with existing measured decay heat rates. Procedures for proper use of the data base, adjustment formulae accounting for effects due to differences in operating history and initial enrichment, and a defensible safety factor were derived. 15 refs., 6 tabs.
Neutron Beta Decay Studies with Nab
Baessler, S.; Alarcon, R.; Alonzi, L. P.; Balascuta, S.; Barron-Palos, L.; Bowman, James David; Bychkov, M. A.; Byrne, J.; Calarco, J; Chupp, T.; Cianciolo, T. V.; Crawford, C.; Frlez, E.; Gericke, M. T.; Glück, F.; Greene, G. L.; Grzywacz, R. K.; Gudkov, V.; Harrison, D.; Hersman, F. W.; Ito, T.; Makela, M.; Martin, J.; McGaughey, P. L.; McGovern, S.; Page, S.; Penttila, Seppo I; Pocanic, Dinko; Salas-Bacci, A.; Tompkins, Z.; Wagner, D.; Wilburn, W. S.; Young, A. R.
2013-01-01
Precision measurements in neutron beta decay serve to determine the coupling constants of beta decay and allow for several stringent tests of the standard model. This paper discusses the design and the expected performance of the Nab spectrometer.
137 Ba Double Gamma Decay Measurement with GAMMASPHERE
Merchán, E.; Moran, K.; Lister, C. J.; Chowdhury, P.; McCutchan, E. A.; Greene, J. P.; Zhu, S.; Lauritsen, T.; Carpenter, M. P.; Shearman, R.
2015-05-28
The study of the electromagnetic moments (EM), and decay probability, provides detailed information about nuclear wave functions. The well-know properties of EM interactions are good for extracting information about the motion of nucleons. Higher order EM processes always occur, but are usually too weak to be measured. In the case of a 0+ → 0+ transitions, where a single gamma transition is forbidden, the simultaneous emission of two γ-rays has been studied. An interesting opportunity to further investigate 2-photon emission phenomena is by using a standard 137Cs source populating, via β-decay, the Jπ = 11/2- isomeric state at 662 keVmore » in 137Ba. In this case, two photon process can have contributions from quadrupole-quadrupole or dipole-octupole multipolarities in direct competition with the high multipolarity M4 decay. Since the yield of the double gamma decay is around six orders of magnitude less than the first order transition, very good statistics are needed in order to observe the phenomena and great care must be taken to suppress the first-order decay. The Gammasphere array is ideal since its configuration allows a good coverage of the angular distribution and the Compton events can be suppressed. Nevertheless the process to understand and eliminate the Compton background is a challenge. Geant4 simulations were carried out to help understand and correct for those factors.« less
^{137} Ba Double Gamma Decay Measurement with GAMMASPHERE
Merchn, E.; Moran, K.; Lister, C. J.; Chowdhury, P.; McCutchan, E. A.; Greene, J. P.; Zhu, S.; Lauritsen, T.; Carpenter, M. P.; Shearman, R.
2015-05-28
The study of the electromagnetic moments (EM), and decay probability, provides detailed information about nuclear wave functions. The well-know properties of EM interactions are good for extracting information about the motion of nucleons. Higher order EM processes always occur, but are usually too weak to be measured. In the case of a 0^{+} ? 0^{+} transitions, where a single gamma transition is forbidden, the simultaneous emission of two ?-rays has been studied. An interesting opportunity to further investigate 2-photon emission phenomena is by using a standard ^{137}Cs source populating, via ?-decay, the J^{?} = 11/2^{-} isomeric state at 662 keV in ^{137}Ba. In this case, two photon process can have contributions from quadrupole-quadrupole or dipole-octupole multipolarities in direct competition with the high multipolarity M4 decay. Since the yield of the double gamma decay is around six orders of magnitude less than the first order transition, very good statistics are needed in order to observe the phenomena and great care must be taken to suppress the first-order decay. The Gammasphere array is ideal since its configuration allows a good coverage of the angular distribution and the Compton events can be suppressed. Nevertheless the process to understand and eliminate the Compton background is a challenge. Geant4 simulations were carried out to help understand and correct for those factors.
1996-06-01
The goal of this work is to study the behavior of the angular distribution of the electron from the decay of the W boson in a specific rest frame of the W, the Collins-Soper frame. More specifically, the parameter {alpha}{sub 2} from the expression d{sigma}/d(P{sub T}{sup W}){sup 2} d cos {theta}* = k(1 + {alpha}{sub 2} cos {theta}* + {alpha}{sup 2}(cos {theta}*){sup 2}), corresponding to the distribution of cos {theta}* in the Collins-Soper frame, was measured. The experimental value of {alpha}P{sub 2} was compared with the predictions made by E. Mirkes [11] who included the radiative QCD perturbations in the weak-interaction B{sub boson} {r_arrow} lepton + lepton. This experimental value was extracted for the first time using knowledge about how the radiative QCD perturbations will modify the predictions given by the Electro-Weak process only.
Linear and non-linear forced response of a conical, ducted, laminar premixed flame
Karimi, Nader; Brear, Michael J.; Jin, Seong-Ho; Monty, Jason P. [Department of Mechanical Engineering, University of Melbourne, Parkville, 3010 Vic. (Australia)
2009-11-15
This paper presents an experimental study on the dynamics of a ducted, conical, laminar premixed flame subjected to acoustic excitation of varying amplitudes. The flame transfer function is measured over a range of forcing frequencies and equivalence ratios. In keeping with previous works, the measured flame transfer function is in good agreement with that predicted by linear kinematic theory at low amplitudes of acoustic velocity excitation. However, a systematic departure from linear behaviour is observed as the amplitude of the velocity forcing upstream of the flame increases. This non-linearity is mostly in the phase of the transfer function and manifests itself as a roughly constant phase at high forcing amplitude. Nonetheless, as predicted by non-linear kinematic arguments, the response always remains close to linear at low forcing frequencies, regardless of the forcing amplitude. The origin of this phase behaviour is then sought through optical data post-processing. (author)
Baryonic matter perturbations in decaying vacuum cosmology
Marttens, R.F. vom; Zimdahl, W.; Hiplito-Ricaldi, W.S. E-mail: wiliam.ricaldi@ufes.br
2014-08-01
We consider the perturbation dynamics for the cosmic baryon fluid and determine the corresponding power spectrum for a ?(t)CDM model in which a cosmological term decays into dark matter linearly with the Hubble rate. The model is tested by a joint analysis of data from supernovae of type Ia (SNIa) (Constitution and Union 2.1), baryonic acoustic oscillations (BAO), the position of the first peak of the anisotropy spectrum of the cosmic microwave background (CMB) and large-scale-structure (LSS) data (SDSS DR7). While the homogeneous and isotropic background dynamics is only marginally influenced by the baryons, there are modifications on the perturbative level if a separately conserved baryon fluid is included. Considering the present baryon fraction as a free parameter, we reproduce the observed abundance of the order of 5% independently of the dark-matter abundance which is of the order of 32% for this model. Generally, the concordance between background and perturbation dynamics is improved if baryons are explicitly taken into account.
Two surface plasmon decay of plasma oscillations
Kluge, T. Metzkes, J.; Zeil, K.; Bussmann, M.; Schramm, U.; Cowan, T. E.
2015-06-15
The interaction of ultra-intense lasers with solid foils can be used to accelerate ions to high energies well exceeding 60 MeV [Gaillard et al., Phys. Plasmas 18, 056710 (2011)]. The non-linear relativistic motion of electrons in the intense laser radiation leads to their acceleration and later to the acceleration of ions. Ions can be accelerated from the front surface, the foil interior region, and the foil rear surface (target normal sheath acceleration (TNSA), most widely used), or the foil may be accelerated as a whole if sufficiently thin (radiation pressure acceleration). Here, we focus on the most widely used mechanism for laser ion-acceleration of TNSA. Starting from perfectly flat foils, we show by simulations how electron filamentation at or inside the solid leads to spatial modulations in the ions. The exact dynamics depend very sensitively on the chosen initial parameters which has a tremendous effect on electron dynamics. In the case of step-like density gradients, we find evidence that suggests a two-surface-plasmon decay of plasma oscillations triggering a Raileigh-Taylor-like instability.
Optimizing minimum free-energy crossing points in solution: Linear...
Office of Scientific and Technical Information (OSTI)
Optimizing minimum free-energy crossing points in solution: Linear-response free energyspin-flip density functional theory approach Citation Details In-Document Search Title:...
Bremsstrahlung in {alpha} Decay Reexamined
Boie, H.; Scheit, H.; Jentschura, U. D.; Koeck, F.; Lauer, M.; Schwalm, D.; Milstein, A. I.; Terekhov, I. S.
2007-07-13
A high-statistics measurement of bremsstrahlung emitted in the {alpha} decay of {sup 210}Po has been performed, which allows us to follow the photon spectra up to energies of {approx}500 keV. The measured differential emission probability is in good agreement with our theoretical results obtained within the quasiclassical approximation as well as with the exact quantum mechanical calculation. It is shown that, due to the small effective electric dipole charge of the radiating system, a significant interference between the electric dipole and quadrupole contributions occurs, which is altering substantially the angular correlation between the {alpha} particle and the emitted photon.
Gravitational effects on inflaton decay
Ema, Yohei; Jinno, Ryusuke; Mukaida, Kyohei; Nakayama, Kazunori
2015-05-22
We point out that the inflaton inevitably couples to all non-conformally coupled matters gravitationally through an oscillation in the Hubble parameter or the cosmic scale factor. It leads to particle production during the inflaton oscillation regime, which is most efficient just after inflation. Moreover, the analysis is extended to the model with non-minimal inflaton couplings to gravity, in which the Hubble parameter oscillates more violently. We apply our results to the graviton production by the inflaton: gravitons are also produced just after inflation, but the non-minimal coupling does not induce inflaton decay into the graviton pair.
Proton decay from the isoscalar giant dipole resonance in {sup 58}Ni
Hunyadi, M.; Hashimoto, H.; Fujimura, H.; Fujiwara, M.; Hara, K.; Itoh, M.; Nakanishi, K.; Okumura, S.; Li, T.; Garg, U.; Hoffman, J.; Nayak, B. K.; Akimune, H.; Gacsi, Z.; Harakeh, M. N.
2009-10-15
Proton decay from the 3({Dirac_h}/2{pi}){omega} isoscalar giant dipole resonance (ISGDR) in {sup 58}Ni has been measured using the ({alpha},{alpha}{sup '}p) reaction at a bombarding energy of 386 MeV to investigate its decay properties. We have extracted the ISGDR strength under the coincidence condition between inelastically scattered {alpha} particles at forward angles and decay protons emitted at backward angles. Branching ratios for proton decay to low-lying states of {sup 57}Co have been determined, and the results compared with predictions of recent continuum-RPA calculations. The final-state spectra of protons decaying to the low-lying states in {sup 57}Co were analyzed for a more detailed understanding of the structure of the ISGDR. It is found that there are differences in the structure of the ISGDR as a function of excitation energy.
Kong, Kyoungchul; Lee, Hye-Sung; Park, Myeonghun
2014-04-01
We suggest top quark decays as a venue to search for light dark force carriers. The top quark is the heaviest particle in the standard model whose decays are relatively poorly measured, allowing sufficient room for exotic decay modes from new physics. A very light (GeV scale) dark gauge boson (Z') is a recently highlighted hypothetical particle that can address some astrophysical anomalies as well as the 3.6sigma deviation in the muon g-2 measurement. We present and study a possible scenario that top quark decays as t-->bW+Z's. This is the same as the dominant top quark decay (t-->bW) accompanied by one or multiple dark force carriers. The Z' can be easily boosted, and it can decay into highly collimated leptons (lepton-jet) with large branching ratio. We discuss the implications for the Large Hadron Collider experiments including the analysis based on the lepton-jets.
Kong, Kyoungchul; Lee, Hye -Sung; Park, Myeonghun
2014-04-01
We suggest top quark decays as a venue to search for light dark force carriers. Top quark is the heaviest particle in the standard model whose decays are relatively poorly measured, allowing sufficient room for exotic decay modes from new physics. A very light (GeV scale) dark gauge boson (Z') is a recently highlighted hypothetical particle that can address some astrophysical anomalies as well as the 3.6 σ deviation in the muon g-2 measurement. We present and study a possible scenario that top quark decays as t → b W + Z's. This is the same as the dominant top quark decay (t → b W) accompanied by one or multiple dark force carriers. The Z' can be easily boosted, and it can decay into highly collimated leptons (lepton-jet) with large branching ratio. In addition, we discuss the implications for the Large Hadron Collider experiments including the analysis based on the lepton-jets.
Cyclotron Institute » Precision Online Decay Facility
U.S. Department of Energy (DOE) all webpages (Extended Search)
Precision Online Decay Facility Precision Decay Station Measurements in nuclear beta decay provide the most precise information available on the unitarity of the CKM matrix, a key test for the possible existence of physics beyond the Standard Model. Extremely pure isotopic samples are produced from the MARS recoil spectrometer (in the case of 22Mg the beam was >99.9% pure). The fast tape-transport system is then used to move the collected samples to a shielded counting position where
Combustion powered linear actuator
Fischer, Gary J.
2007-09-04
The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.
Bosamykin, V.S.; Pavlovskiy, A.I.
1984-03-01
A linear induction accelerator of charged particles, containing inductors and an acceleration circuit, characterized by the fact that, for the purpose of increasing the power of the accelerator, each inductor is made in the form of a toroidal line with distributed parameters, from one end of which in the gap of the line a ring commutator is included, and from the other end of the ine a resistor is hooked up, is described.
Buttram, M.T.; Ginn, J.W.
1988-06-21
A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.
Experimental Survey of Strange Particle Decays
DOE R&D Accomplishments [OSTI]
Steinberger, J.
1964-06-01
It is the aim of these three lectures to summarize the present experimental knowledge concerning the decays of the strange particles.
Tensor mesons produced in tau lepton decays
Lopez Castro, G.; Munoz, J. H.
2011-05-01
Light tensor mesons (T=a{sub 2}, f{sub 2} and K{sub 2}*) can be produced in decays of {tau} leptons. In this paper we compute the branching ratios of {tau}{yields}T{pi}{nu} decays by assuming the dominance of intermediate virtual states to model the form factors involved in the relevant hadronic matrix elements. The exclusive f{sub 2}(1270){pi}{sup -} decay mode turns out to have the largest branching ratio, of O(10{sup -4}). Our results indicate that the contribution of tensor meson intermediate states to the three-pseudoscalar channels of {tau} decays are rather small.
Radiative Decays Involving Light Scalar Mesons
Deirdre Black; Masayasu Harada; Joseph Schechter
2002-09-01
We present a vector dominance model to describe radiative decays involving the light scalar mesons. Assuming that the light scalar mesons form a nonet this model gives relations among various decay amplitudes of the form S--> gamma gamma, V-->Sgamma and S--> Vgamma, where S and V denote scalar and vector mesons. By comparing with experimental radiative decay rates, including those recently measured for phi--> PP'gamma, we obtain various predictions. We discuss briefly ongoing extensions of the present work in an attempt to describe the radiative phi decay measurements in detail.
Novel Photoconductive Decay Measurement System - Energy Innovation...
U.S. Department of Energy (DOE) all webpages (Extended Search)
Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Novel Photoconductive Decay Measurement System Colorado School of Mines Contact CSM About This Technology...
Recent developments in the theory of double beta decay
Iachello, F.; Kotila, J.; Barea, J.
2013-12-30
We report results of a novel calculation of phase space factors for 2??{sup +}?{sup +}, 2??{sup +}EC, 2?ECEC, 0??{sup +}?{sup +}, and 0??{sup +}EC using exact Dirac wave functions, and finite nuclear size and electron screening corrections. We present results of expected half-lives for 0??{sup +}?{sup +} and 0??{sup +}EC decays obtained by combining the calculation of phase space factors with IBM-2 nuclear matrix elements.
Decay of transverse correlations in quantum Heisenberg models
Björnberg, Jakob E. E-mail: daniel@ueltschi.org; Ueltschi, Daniel E-mail: daniel@ueltschi.org
2015-04-15
We study a class of quantum spin systems that include the S=1/2 Heisenberg and XY-models and prove that two-point correlations exhibit exponential decay in the presence of a transverse magnetic field. The field is not necessarily constant, it may be random, and it points in the same direction. Our proof is entirely probabilistic and it relies on a random loop representations of the correlation functions, on stochastic domination and on first-passage percolation.
Spectroscopy and decays of charm and bottom
Butler, J.N.
1997-10-01
After a brief review of the quark model, we discuss our present knowledge of the spectroscopy of charm and bottom mesons and baryons. We go on to review the lifetimes, semileptonic, and purely leptonic decays of these particles. We conclude with a brief discussion B and D mixing and rare decays.
Linear Fresnel | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Concentrating Solar Power » Linear Fresnel Linear Fresnel DOE funds solar research and development (R&D) in linear Fresnel systems as one of four CSP technologies aiming to meet the goals of the SunShot Initiative. Linear Fresnel systems, which are a type of linear concentrator, are active in Germany, Spain, Australia, India, and the United States. The SunShot Initiative funds R&D on linear Fresnel systems and related aspects within the industry, national laboratories and universities
Acosta, D.; Affolder, Anthony A.; Albrow, M.G.; Ambrose, D.; Amidei, D.; Anikeev, K.; Antos, J.; Apollinari, G.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Azfar, F.; Azzi-Bacchetta, P.; Bacchetta, N.; Bachacou, H.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Baroiant, S.; Barone, M.; /Taiwan, Inst. Phys. /Argonne /INFN, Bologna /Bologna U. /Brandeis U. /UC, Davis /UCLA /UC, Santa Barbara /Cantabria Inst. of Phys. /Carnegie Mellon U. /Chicago U., EFI /Dubna, JINR /Duke U. /Fermilab /Florida U. /Frascati /Geneva U. /Glasgow U. /Harvard U. /Hiroshima U. /Illinois U., Urbana
2005-04-01
We present the first measurement of the A{sub 2} and A{sub 3} angular coefficients of the W boson produced in proton-antiproton collisions. We study W {yields} ev{sub e} and W {yields} {mu}{nu}{sub {mu}} candidate events produced in association with at least one jet at CDF, during Run Ia and Run Ib of the Tevatron at {radical}s = 1.8 TeV. The corresponding integrated luminosity was 110 pb{sup -1}. The jet balances the transverse momentum of the W and introduces QCD effects in W boson production. The extraction of the angular coefficients is achieved through the direct measurement of the azimuthal angle of the charged lepton in the Collins-Soper rest-frame of the W boson. The angular coefficients are measured as a function of the transverse momentum of the W boson. The electron, muon, and combined results are in good agreement with the Standard Model prediction, up to order {alpha}{sub s}{sup 2} in QCD.
Artuso, M.; Asner, D.M.; Ball, P.; Baracchini, E.; Bell, G.; Beneke, M.; Berryhill, J.; Bevan, A.; Bigi, I.I.; Blanke, M.; Bobeth, Ch.; Bona, M.; Borzumati, F.; Browder, T.; Buanes, T.; Buchalla, G.; Buchmuller, O.; Buras, A.J.; Burdin, S.; Cassel, D.G.; Cavanaugh, R.; /Syracuse U. /Carleton U. /Durham U., IPPP /Rome U. /INFN, Rome /Karlsruhe U. /RWTH Aachen U. /Fermilab /Queen Mary, U. of London /Notre Dame U. /Munich, Tech. U. /Munich, Max Planck Inst. /Dortmund U. /Annecy, LAPP /ICTP, Trieste /Taiwan, Natl. Central U. /Hawaii U. /Bergen U. /Munich U. /CERN /Liverpool U.
2008-03-07
The present report documents the results of Working Group 2: B, D and K decays, of the workshop on Flavor in the Era of the LHC, held at CERN from November 2005 through March 2007. With the advent of the LHC, we will be able to probe New Physics (NP) up to energy scales almost one order of magnitude larger than it has been possible with present accelerator facilities. While direct detection of new particles will be the main avenue to establish the presence of NP at the LHC, indirect searches will provide precious complementary information, since most probably it will not be possible to measure the full spectrum of new particles and their couplings through direct production. In particular, precision measurements and computations in the realm of flavor physics are expected to play a key role in constraining the unknown parameters of the Lagrangian of any NP model emerging from direct searches at the LHC. The aim of Working Group 2 was twofold: on one hand, to provide a coherent, up-to-date picture of the status of flavor physics before the start of the LHC; on the other hand, to initiate activities on the path towards integrating information on NP from high-p{sub T} and flavor data. This report is organized as follows. In Sec. 1, we give an overview of NP models, focusing on a few examples that have been discussed in some detail during the workshop, with a short description of the available computational tools for flavor observables in NP models. Sec. 2 contains a concise discussion of the main theoretical problem in flavor physics: the evaluation of the relevant hadronic matrix elements for weak decays. Sec. 3 contains a detailed discussion of NP effects in a set of flavor observables that we identified as 'benchmark channels' for NP searches. The experimental prospects for flavor physics at future facilities are discussed in Sec. 4. Finally, Sec. 5 contains some assessments on the work done at the workshop and the prospects for future developments.
Energy Science and Technology Software Center (OSTI)
2006-11-17
Software that simulates and inverts electromagnetic field data for subsurface electrical properties (electrical conductivity) of geological media. The software treats data produced by a time harmonic source field excitation arising from the following antenna geometery: loops and grounded bipoles, as well as point electric and magnetic dioples. The inversion process is carried out using a non-linear conjugate gradient optimization scheme, which minimizes the misfit between field data and model data using a least squares criteria.more » The software is an upgrade from the code NLCGCS_MP ver 1.0. The upgrade includes the following components: Incorporation of new 1 D field sourcing routines to more accurately simulate the 3D electromagnetic field for arbitrary geologic& media, treatment for generalized finite length transmitting antenna geometry (antennas with vertical and horizontal component directions). In addition, the software has been upgraded to treat transverse anisotropy in electrical conductivity.« less
Positrons for linear colliders
Ecklund, S.
1987-11-01
The requirements of a positron source for a linear collider are briefly reviewed, followed by methods of positron production and production of photons by electromagnetic cascade showers. Cross sections for the electromagnetic cascade shower processes of positron-electron pair production and Compton scattering are compared. A program used for Monte Carlo analysis of electromagnetic cascades is briefly discussed, and positron distributions obtained from several runs of the program are discussed. Photons from synchrotron radiation and from channeling are also mentioned briefly, as well as positron collection, transverse focusing techniques, and longitudinal capture. Computer ray tracing is then briefly discussed, followed by space-charge effects and thermal heating and stress due to showers. (LEW)
Van Atta, C.M.; Beringer, R.; Smith, L.
1959-01-01
A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.
Dark matter gravitinos and baryons via Q-ball decay in the gauge-mediated MSSM
Doddato, Francesca; McDonald, John E-mail: j.mcdonald@lancaster.ac.uk
2013-07-01
We show that late Q-ball decay in the MSSM with gauge-mediated SUSY breaking can provide a natural source of non-thermal NLSPs which subsequently decay to gravitino dark matter without violating nucleosynthesis constraints. To show this, we perform a global analysis of Q-ball formation and decay in Affleck-Dine baryogenesis for a d = 6 (u{sup c}d{sup c}d{sup c}){sup 2} flat direction of the gauge-mediated MSSM. A general phenomenological potential for the flat-direction is studied and the Q-ball decay properties are obtained as a function of its parameters. The corresponding gravitino mass necessary to account for dark matter is then determined for the case of stau NLSPs. The decay temperature depends on the charge of the Q-balls, which is determined by the fragmentation of the AD condensate. Different fragmentation scenarios are considered, and the final non-thermal NLSP density from Q-ball decay and NLSP annihilation is determined. Particular care is taken to establish that NLSPs from Q-ball decay become homogeneous and non-relativistic prior to annihilation. The gravitino mass necessary for dark matter is naturally consistent with the theoretical gravitino mass in the gauge-mediation model.
Use of Integrated Decay Heat Limits to Facilitate Spent Nuclear Fuel Loading to Yucca Mountain
Li, Jun; Yim, Man-Sung; McNelis, David; Piet, Steven
2007-07-01
As an alternative to the use of the linear loading or areal power density (APD) concept, using integrated decay heat limits based on the use of mountain-scale heat transfer analysis is considered to represent the thermal impact from the deposited spent nuclear fuel (SNF) to the Yucca Mountain repository. Two different integrated decay heat limits were derived to represent both the short-term (up to 50 years from the time of repository closure) and the long-term decay heat effect (up to 1500 years from the time of repository closure). The derived limits were found to appropriately represent the drift wall temperature limit (200 deg. C) and the midway between adjacent drifts temperature limit (96 deg. C) as long as used fuel is uniformly loaded into the mountain. These limits can be a useful practical guide to facilitate the loading of used fuel into Yucca Mountain. (authors)
Rare top quark and Higgs boson decays in alternative left-right symmetric models
Gaitan, R.; Miranda, O.G.; Cabral-Rosetti, L.G.
2005-08-01
Top quark and Higgs boson decays induced by flavor-changing neutral currents (FCNC) are very much suppressed in the standard model. Their detection in colliders such as the Large Hadron Collider, Next Linear Collider, or Tevatron would be a signal of new physics. We evaluate the FCNC decays t{yields}H{sup 0}+c, t{yields}Z+c, and H{sup 0}{yields}t+c in the context of alternative left-right symmetric models with extra isosinglet heavy fermions; in this case, FCNC decays occur at tree level, and they are suppressed only by the mixing between ordinary top and charm quarks, which is poorly constrained by current experimental values. This provides the possibility for future colliders either to detect new physics or to improve present bounds on the parameters of the model.
Neutrino signals from dark matter decay
Covi, Laura; Grefe, Michael; Ibarra, Alejandro; Tran, David E-mail: michael.grefe@desy.de E-mail: david.tran@ph.tum.de
2010-04-01
We investigate different neutrino signals from the decay of dark matter particles to determine the prospects for their detection, and more specifically if any spectral signature can be disentangled from the background in present and future neutrino observatories. If detected, such a signal could bring an independent confirmation of the dark matter interpretation of the dramatic rise in the positron fraction above 10 GeV recently observed by the PAMELA satellite experiment and offer the possibility of distinguishing between astrophysical sources and dark matter decay or annihilation. In combination with other signals, it may also be possible to distinguish among different dark matter decay channels.
Photoproduction and Decay of Light Mesons in CLAS
Amaryan, Moskov Jamalovich
2013-08-01
We present preliminary experimental results on photoproduction and decay of light mesons measured with CLAS setup at JLAB . This include Dalitz decay of pseudoscalar and vector mesons, radiative decay of pseudoscalar mesons as well hadronic decays of pseudoscalar and vector mesons. The collected high statistics in some of decay channels exceeds the world data by an order of magnitude and some other decay modes are observed for the first time. It is shown how the CLAS data will improve the world data on transition form factors of light mesons, Dalitz plot analyses, branching ratios of rare decay modes and other fundamental properties potentially accessible through the light meson decays.
Search for Neutral D Meson Mixing using Semileptonic Decays ...
Office of Scientific and Technical Information (OSTI)
Technical Report: Search for Neutral D Meson Mixing using Semileptonic Decays Citation Details In-Document Search Title: Search for Neutral D Meson Mixing using Semileptonic Decays...
SciTech Connect: "neutrinoless double beta decay"
Office of Scientific and Technical Information (OSTI)
neutrinoless double beta decay" Find + Advanced Search Term Search Semantic Search Advanced Search All Fields: "neutrinoless double beta decay" Semantic Semantic Term Title:...
Nuclear reaction and decay data evaluation capabilities at LANL...
Office of Scientific and Technical Information (OSTI)
Conference: Nuclear reaction and decay data evaluation capabilities at LANL Citation Details In-Document Search Title: Nuclear reaction and decay data evaluation capabilities at ...
Nuclear reaction and decay data evaluation capabilities at LANL...
Office of Scientific and Technical Information (OSTI)
Nuclear reaction and decay data evaluation capabilities at LANL Citation Details In-Document Search Title: Nuclear reaction and decay data evaluation capabilities at LANL You ...
Kliman, G.B.; Brynsvold, G.V.; Jahns, T.M.
1989-08-22
A winding and method of winding for a submersible linear pump for pumping liquid sodium are disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet. 4 figs.
Kliman, Gerald B.; Brynsvold, Glen V.; Jahns, Thomas M.
1989-01-01
A winding and method of winding for a submersible linear pump for pumping liquid sodium is disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet.
Berkeley Proton Linear Accelerator
DOE R&D Accomplishments [OSTI]
Alvarez, L. W.; Bradner, H.; Franck, J.; Gordon, H.; Gow, J. D.; Marshall, L. C.; Oppenheimer, F. F.; Panofsky, W. K. H.; Richman, C.; Woodyard, J. R.
1953-10-13
A linear accelerator, which increases the energy of protons from a 4 Mev Van de Graaff injector, to a final energy of 31.5 Mev, has been constructed. The accelerator consists of a cavity 40 feet long and 39 inches in diameter, excited at resonance in a longitudinal electric mode with a radio-frequency power of about 2.2 x 10{sup 6} watts peak at 202.5 mc. Acceleration is made possible by the introduction of 46 axial "drift tubes" into the cavity, which is designed such that the particles traverse the distance between the centers of successive tubes in one cycle of the r.f. power. The protons are longitudinally stable as in the synchrotron, and are stabilized transversely by the action of converging fields produced by focusing grids. The electrical cavity is constructed like an inverted airplane fuselage and is supported in a vacuum tank. Power is supplied by 9 high powered oscillators fed from a pulse generator of the artificial transmission line type.
Meisner, John W.; Moore, Robert M.; Bienvenue, Louis L.
1985-03-19
Electromagnetic linear induction pump for liquid metal which includes a unitary pump duct. The duct comprises two substantially flat parallel spaced-apart wall members, one being located above the other and two parallel opposing side members interconnecting the wall members. Located within the duct are a plurality of web members interconnecting the wall members and extending parallel to the side members whereby the wall members, side members and web members define a plurality of fluid passageways, each of the fluid passageways having substantially the same cross-sectional flow area. Attached to an outer surface of each side member is an electrically conductive end bar for the passage of an induced current therethrough. A multi-phase, electrical stator is located adjacent each of the wall members. The duct, stators, and end bars are enclosed in a housing which is provided with an inlet and outlet in fluid communication with opposite ends of the fluid passageways in the pump duct. In accordance with a preferred embodiment, the inlet and outlet includes a transition means which provides for a transition from a round cross-sectional flow path to a substantially rectangular cross-sectional flow path defined by the pump duct.
Higgs Coupling Measurements at a 1 TeV Linear Collider
Barklow, T
2003-12-18
Methods for extracting Higgs boson signals at a 1 TeV center-of-mass energy e{sup +}e{sup -} linear collider are described. In addition, estimates are given for the accuracy with which branching fractions can be measured for Higgs boson decays to b{bar b} WW, gg, and {gamma}{gamma}.
Probing the Planck Scale with Proton Decay
Harnik, Roni; Larson, Daniel T.; Murayama, Hitoshi; Thormeier, Marc
2004-04-28
We advocate the idea that proton decay may probe physics at the Planck scale instead of the GUT scale. This is possible because supersymmetric theories have dimension-5 operators that can induce proton decay at dangerous rates, even with R-parity conservation. These operators are expected to be suppressed by the same physics that explains the fermion masses and mixings. We present a thorough analysis of nucleon partial lifetimes in models with a string-inspired anomalous U(1)_X family symmetry which is responsible for the fermionic mass spectrum as well as forbidding R-parity violating interactions. Protons and neutrons can decay via R-parity conserving non-renormalizable superpotential terms that are suppressed by the Planck scale and powers of the Cabibbo angle. Many of the models naturally lead to nucleon decay near present limits without any reference to grand unification.
Rare charm and B decays at CDF
Julia Thom
2003-12-15
We present results on rare charm and B decays using 65pb{sup -1} of data taken with the CDF detector in Run II. Three results are discussed, a measurement of the relative branching ratios {Lambda}(D{sup 0} {yields} K{sup +}K{sup -})/{Lambda}(D{sup 0} {yields} K{pi}) and {Lambda}(D{sup 0} {yields} {pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{pi}) and the direct CP-violating decay rate asymmetry, and a limit on the branching ratio of the FCNC decay D{sup 0} {yields} {mu}{sup +}{mu}{sup -}. We also discuss the prospects for the search for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays.
Review of modern double beta decay experiments
Barabash, A. S.
2015-10-28
The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T{sub 1/2}(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino (〈m{sub ν}〉 < 0.46 eV) and a coupling constant of Majoron to neutrino (〈g{sub ee}〉 < 1.3 · 10{sup −5}) are obtained. Prospects of search for neutrinoless double beta decay in new experiments with sensitivity to 〈m{sub ν}〉 at the level of ∼ 0.01-0.1 eV are discussed.
Linear response of tripartite entanglement to infinitesimal noise
Zhang, Fu-Lin; Chen, Jing-Ling
2014-10-15
Recent experimental progress in prolonging the coherence time of a quantum system prompts us to explore the behavior of quantum entanglement at the beginning of the decoherence process. The response of the entanglement under an infinitesimal noise can serve as a signature of the robustness of entangled states. A crucial problem of this topic in multipartite systems is to compute the degree of entanglement in a mixed state. We find a family of global noise in three-qubit systems, which is composed of four W states. Under its influence, the linear response of the tripartite entanglement of a symmetrical three-qubit pure state is studied. A lower bound of the linear response is found to depend completely on the initial tripartite and bipartite entanglement. This result shows that the decay of tripartite entanglement is hastened by the bipartite one. - Highlights: • We study a set of W-type noise and its linear effect on symmetric pure states. • Its effect on two-qubit entanglement depends only on the initial concurrence. • A lower bound of the effect on 3-tangle is found in terms of initial entanglements. • We obtain the time of three-tangle sudden death for two families of typical states. • These reveal that the bipartite entanglement speeds up the decay of the tripartite one.
Rare top quark decays in extended models
Gaitan, R.; Miranda, O. G.; Cabral-Rosetti, L. G.
2006-09-25
Flavor changing neutral currents (FCNC) decays t {yields} H0 + c, t {yields} Z + c, and H0 {yields} t + c-bar are discussed in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions where FCNC decays may take place at tree-level and are only suppressed by the mixing between ordinary top and charm quarks, which is poorly constraint by current experimental values. The non-manifest case is also briefly discussed.
THE DECAYING LONG-PERIOD OSCILLATION OF A STELLAR MEGAFLARE
Anfinogentov, S.; Nakariakov, V. M.; Mathioudakis, M.; Van Doorsselaere, T.; Kowalski, A. F.
2013-08-20
We analyze and interpret the oscillatory signal in the decay phase of the U-band light curve of a stellar megaflare observed on 2009 January 16 on the dM4.5e star YZ CMi. The oscillation is well approximated by an exponentially decaying harmonic function. The period of the oscillation is found to be 32 minutes, the decay time about 46 minutes, and the relative amplitude 15%. As this observational signature is typical of the longitudinal oscillations observed in solar flares at extreme ultraviolet and radio wavelengths, associated with standing slow magnetoacoustic waves, we suggest that this megaflare may be of a similar nature. In this scenario, macroscopic variations of the plasma parameters in the oscillations modulate the ejection of non-thermal electrons. The phase speed of the longitudinal (slow magnetoacoustic) waves in the flaring loop or arcade, the tube speed, of about 230 km s{sup -1} would require a loop length of about 200 Mm. Other mechanisms, such as standing kink oscillations, are also considered.
Gamma-ray decay of levels in /sup 53/Cr
Dickens, J.K.; Larson, D.C.
1987-11-01
Gamma-ray decay of levels in the stable isotope /sup 53/Cr has been studied using /sup 53/Cr(n,n'..gamma..) reactions for incident neutron energies between threshold and 10 MeV. Of the 65 gamma rays or gamma-ray groups observed for neutron interactions with /sup 53/Cr, 50 have been placed or tentatively placed among 34 levels in /sup 53/Cr up to an excitation energy of 4.36 MeV. Deduced branching ratios are in reasonable agreement with previous measurements except for decay of the E/sub x/ = 1537-keV level. For the decay of the E/sub x/ = 1537-keV level we are unable to explain variations in the branching ratios of the transition gamma rays as a function of incident neutron energy within the framework of the presently known level structure of /sup 53/Cr and suggest the possibility of a second energy level at E/sub x/ = 1537 keV. 59 refs., 13 figs., 2 tabs.
Kong, Kyoungchul; Lee, Hye -Sung; Park, Myeonghun
2014-04-01
We suggest top quark decays as a venue to search for light dark force carriers. Top quark is the heaviest particle in the standard model whose decays are relatively poorly measured, allowing sufficient room for exotic decay modes from new physics. A very light (GeV scale) dark gauge boson (Z') is a recently highlighted hypothetical particle that can address some astrophysical anomalies as well as the 3.6 σ deviation in the muon g-2 measurement. We present and study a possible scenario that top quark decays as t → b W + Z's. This is the same as the dominant topmore » quark decay (t → b W) accompanied by one or multiple dark force carriers. The Z' can be easily boosted, and it can decay into highly collimated leptons (lepton-jet) with large branching ratio. In addition, we discuss the implications for the Large Hadron Collider experiments including the analysis based on the lepton-jets.« less
Parametric decay of an extraordinary electromagnetic wave in relativistic plasma
Dorofeenko, V. G.; Krasovitskiy, V. B.; Turikov, V. A.
2015-03-15
Parametric instability of an extraordinary electromagnetic wave in plasma preheated to a relativistic temperature is considered. A set of self-similar nonlinear differential equations taking into account the electron “thermal” mass is derived and investigated. Small perturbations of the parameters of the heated plasma are analyzed in the linear approximation by using the dispersion relation determining the phase velocities of the fast and slow extraordinary waves. In contrast to cold plasma, the evanescence zone in the frequency range above the electron upper hybrid frequency vanishes and the asymptotes of both branches converge. Theoretical analysis of the set of nonlinear equations shows that the growth rate of decay instability increases with increasing initial temperature of plasma electrons. This result is qualitatively confirmed by numerical simulations of plasma heating by a laser pulse injected from vacuum.
Evolution of density perturbations in decaying vacuum cosmology
Borges, H. A.; Pigozzo, C.; Carneiro, S.; Fabris, J. C.
2008-02-15
We study cosmological perturbations in the context of an interacting dark energy model, in which the cosmological term decays linearly with the Hubble parameter, with concomitant matter production. A previous joint analysis of the redshift-distance relation for type Ia supernovas, barionic acoustic oscillations, and the position of the first peak in the anisotropy spectrum of the cosmic microwave background has led to acceptable values for the cosmological parameters. Here we present our analysis of small perturbations, under the assumption that the cosmological term, and therefore the matter production, are strictly homogeneous. Such a homogeneous production tends to dilute the matter contrast, leading to a late-time suppression in the power spectrum. Nevertheless, an excellent agreement with the observational data can be achieved by using a higher matter density as compared to the concordance value previously obtained. This may indicate that our hypothesis of homogeneous matter production must be relaxed by allowing perturbations in the interacting cosmological term.
The TESLA superconducting linear collider
the TESLA Collaboration
1997-03-01
This paper summarizes the present status of the studies for a superconducting Linear Collider (TESLA). {copyright} {ital 1997 American Institute of Physics.}
Efficient double beta decay nuclear matrix elements computations
Neacsu, Andrei [Horia Hulubei Foundation (FHH) 407 Atomistilor, Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH) 30 Reactorului, Magurele-Bucharest 077125 (Romania)
2012-11-20
We have developed a shell model code for the accurate computation of the two-body matrix elements of the transition operators involved in the neutrinoless double beta decay. This code features coupled cluster method short-range correlations with Jastrow-like functions, finite nucleon size effect and higher order nucleon current corrections. We present the results obtained for {sup 48}Ca and {sup 82}Se, then we compare them with other results in the literature. In the case of {sup 48}Ca, we also study the contributions of the included effects and find good agreement with other published results.
Inpainting with sparse linear combinations of exemplars
Wohlberg, Brendt
2008-01-01
We introduce a new exemplar-based inpainting algorithm based on representing the region to be inpainted as a sparse linear combination of blocks extracted from similar parts of the image being inpainted. This method is conceptually simple, being computed by functional minimization, and avoids the complexity of correctly ordering the filling in of missing regions of other exemplar-based methods. Initial performance comparisons on small inpainting regions indicate that this method provides similar or better performance than other recent methods.
Method and apparatus of highly linear optical modulation
DeRose, Christopher; Watts, Michael R.
2016-05-03
In a new optical intensity modulator, a nonlinear change in refractive index is used to balance the nonlinearities in the optical transfer function in a way that leads to highly linear optical intensity modulation.
Neutrino decay and neutrinoless double beta decay in a 3-3-1 model
Dias, Alex G. [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66.318, 05315-970, Sao Paulo-SP (Brazil); Doff, A. [Instituto de Fisica Teorica, Universidade Estadual Paulista, Rua Pamplona 145, 01405-900 Sao Paulo-SP (Brazil); Pires, C.A. de S; Rodrigues da Silva, P.S. [Departamento de Fisica, Universidade Federal da Paraiba, Caixa Postal 5008, 58051-970, Joao Pessoa-PB (Brazil)
2005-08-01
In this work we show that the implementation of spontaneous breaking of the lepton number in the 3-3-1 model with right-handed neutrinos gives rise to fast neutrino decay with Majoron emission and generates a bunch of new contributions to the neutrinoless double beta decay.
Monorchio, Diego; /INFN, Naples /Naples U.
2011-09-13
The authors will present the most recent results on leptonic B decays B{sup {+-}(0)} {yields} K*{sup {+-}(0)} {nu}{bar {nu}} and B{sup {+-}} {yields} {mu}{sup {+-}}{nu}, based on the data collected by the BaBar detector at PEP-II, an asymmetric e{sup +}e{sup -} collider at the center of mass energy of the {Upsilon}(4S) resonance. Rare B decays have always been a standard probe for New Physics (NP) searches. The very low Standard Model (SM) rate of these decays often make them unaccessible with the present experimental datasets, unless NP effects enhance the rate up to the current experimental sensitivity. Moreover, as NP effects can modify the decay kinematic, particular attention must be payed in order to perform a model independent analysis. A B-Factory provides an unique environment where to investigate these processes. The high number of B{bar B} pairs produced by a B-Factory often allows to approach the needed experimental sensitivity. Moreover, the clean environment and the closed kinematic of the initial state enable to obtaining a very pure sample where to look for these decays.
Baracchini, Elisabetta; /Rome U. /INFN, Rome
2011-11-10
We will present the most recent results on leptonic B decays B{sup {+-}(0)} {yields} K*{sup {+-}(0)}{nu}{bar {nu}} and B{sup {+-}} {yields} {mu}{sup {+-}}{nu}, based on the data collected by the BaBar detector at PEP-II, an asymmetric e{sup +}e{sup -} collider at the center of mass energy of the {Upsilon}(4S) resonance. Rare B decays have always been a standard probe for New Physics (NP) searches. The very low Standard Model (SM) rate of these decays often make them unaccessible with the present experimental datasets, unless NP effects enhance the rate up to the current experimental sensitivity. Moreover, as NP effects can modify the decay kinematic, particular attention must be paid in order to perform a model independent analysis. A B-Factory provides an unique environment to investigate these processes. The high number of B{bar B} pairs produced by a B-Factory often allows to approach the needed experimental sensitivity. Moreover, the clean environment and the closed kinematic of the initial state enable to obtaining a very pure sample where to look for these decays.
Non-linear system identification in flow-induced vibration
Spanos, P.D.; Zeldin, B.A.; Lu, R.
1996-12-31
The paper introduces a method of identification of non-linear systems encountered in marine engineering applications. The non-linearity is accounted for by a combination of linear subsystems and known zero-memory non-linear transformations; an equivalent linear multi-input-single-output (MISO) system is developed for the identification problem. The unknown transfer functions of the MISO system are identified by assembling a system of linear equations in the frequency domain. This system is solved by performing the Cholesky decomposition of a related matrix. It is shown that the proposed identification method can be interpreted as a {open_quotes}Gram-Schmidt{close_quotes} type of orthogonal decomposition of the input-output quantities of the equivalent MISO system. A numerical example involving the identification of unknown parameters of flow (ocean wave) induced forces on offshore structures elucidates the applicability of the proposed method.
Inclusive radiative {psi}(2S) decays
Libby, J.; Martin, L.; Powell, A.; Thomas, C.; Wilkinson, G.; Mendez, H.; Ge, J. Y.; Miller, D. H.; Shipsey, I. P. J.; Xin, B.; Adams, G. S.; Hu, D.; Moziak, B.; Napolitano, J.; Ecklund, K. M.; He, Q.; Insler, J.; Muramatsu, H.; Park, C. S.; Thorndike, E. H.
2009-10-01
Using e{sup +}e{sup -} collision data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct photon spectrum in the decay {psi}(2S){yields}{gamma}gg. We determine the ratio of the inclusive direct photon decay rate to that of the dominant three-gluon decay rate {psi}(2S){yields}ggg (R{sub {gamma}}{identical_to}{gamma}({gamma}gg)/{gamma}(ggg)) to be R{sub {gamma}}(z{sub {gamma}}>0.4)=0.070{+-}0.002{+-}0.019{+-}0.011, with z{sub {gamma}} defined as the scaled photon energy relative to the beam energy. The errors shown are statistical, systematic, and that due to the uncertainty in the input branching fractions used to extract the ratio, respectively.
Neutrinoless double beta decay and neutrino masses
Duerr, Michael [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)
2012-07-27
Neutrinoless double beta decay (0{nu}{beta}{beta}) is a promising test for lepton number violating physics beyond the standard model (SM) of particle physics. There is a deep connection between this decay and the phenomenon of neutrino masses. In particular, we will discuss the relation between 0{nu}{beta}{beta} and Majorana neutrino masses provided by the so-called Schechter-Valle theorem in a quantitative way. Furthermore, we will present an experimental cross check to discriminate 0{nu}{beta}{beta} from unknown nuclear background using only one isotope, i.e., within one experiment.
The double-beta decay: Theoretical challenges
Horoi, Mihai
2012-11-20
Neutrinoless double beta decay is a unique process that could reveal physics beyond the Standard Model of particle physics namely, if observed, it would prove that neutrinos are Majorana particles. In addition, it could provide information regarding the neutrino masses and their hierarchy, provided that reliable nuclear matrix elements can be obtained. The two neutrino double beta decay is an associate process that is allowed by the Standard Model, and it was observed for about ten nuclei. The present contribution gives a brief review of the theoretical challenges associated with these two process, emphasizing the reliable calculation of the associated nuclear matrix elements.
Linear Accelerator | Advanced Photon Source
U.S. Department of Energy (DOE) all webpages (Extended Search)
Linear Accelerator Producing brilliant x-ray beams at the APS begins with electrons emitted from a cathode heated to 1100 C. The electrons are accelerated by high-voltage...
Acoustic emission linear pulse holography
Collins, H.D.; Busse, L.J.; Lemon, D.K.
1983-10-25
This device relates to the concept of and means for performing Acoustic Emission Linear Pulse Holography, which combines the advantages of linear holographic imaging and Acoustic Emission into a single non-destructive inspection system. This unique system produces a chronological, linear holographic image of a flaw by utilizing the acoustic energy emitted during crack growth. The innovation is the concept of utilizing the crack-generated acoustic emission energy to generate a chronological series of images of a growing crack by applying linear, pulse holographic processing to the acoustic emission data. The process is implemented by placing on a structure an array of piezoelectric sensors (typically 16 or 32 of them) near the defect location. A reference sensor is placed between the defect and the array.
Neutrinoless double beta decay and nuclear matrix elements
Simkovic, Fedor [BLTP, JINR Dubna, 141980 Dubna, Moscow region (Russian Federation); Comenius University, Mlynska dolina, Bratislava (Slovakia)
2011-11-23
The fundamental importance of searching for neutrinoless double-beta decay (0{nu}{beta}{beta}-decay) is widely recognized. Observation of the decay would tell us that the total lepton number is not conserved and that, consequently, neutrinos are massive Majorana fermions. The 0{nu}{beta}{beta}-decay is discussed in context of neutrino oscillation data. The perspectives of the experimental 0{nu}{beta}{beta}-decay searches are analyzed. The importance of reliable determination of the 0{nu}{beta}{beta}-decay nuclear matrix elements is pointed out.
Minkowski, Peter; Ochs, Wolfgang
2006-02-11
We summarize some persistent problems in scalar spectroscopy and discuss what could be learned here from charmless B-decays. Recent experimental results are discussed in comparison with theoretical expectations: a simple model based on penguin dominance leads to various symmetry relations in good agreement with recent data; a factorisation approach yields absolute predictions of rates.
Exotic decays of heavy B quarks
Fox, Patrick J.; Tucker-Smith, David
2016-01-08
Heavy vector-like quarks of charge –1/3, B, have been searched for at the LHC through the decays B → bZ, bh, tW. In models where the B quark also carries charge under a new gauge group, new decay channels may dominate. We focus on the case where the B is charged under a U(1)' and describe simple models where the dominant decay mode is B → bZ' → b(bb¯¯). With the inclusion of dark matter such models can explain the excess of gamma rays from the Galactic center. We develop a search strategy for this decay chain and estimate thatmore » with integrated luminosity of 300 fb–1 the LHC will have the potential to discover both the B and the Z' for B quarks with mass below ~ 1.6 TeV, for a broad range of Z' masses. Furthermore, a high-luminosity run can extend this reach to 2 TeV.« less
Stabilizing oscillating universes against quantum decay
Mithani, Audrey T.; Vilenkin, Alexander
2015-07-07
We investigate the effect of vacuum corrections, due to the trace anomaly and Casimir effect, on the stability of an oscillating universe with respect to decay by tunneling to the singularity. We find that these corrections do not generally stabilize an oscillating universe. However, stability may be achieved for some specially fine-tuned non-vacuum states.
New insights into the decay of ion waves to turbulence, ion heating, and soliton generation
Chapman, T. Banks, J. W.; Berger, R. L.; Cohen, B. I.; Williams, E. A.; Brunner, S.
2014-04-15
The decay of a single-frequency, propagating ion acoustic wave (IAW) via two-ion wave decay to a continuum of IAW modes is found to result in a highly turbulent plasma, ion soliton production, and rapid ion heating. Instability growth rates, thresholds, and sensitivities to plasma conditions are studied via fully kinetic Vlasov simulations. The decay rate of IAWs is found to scale linearly with the fundamental IAW potential amplitude ϕ{sub 1} for ZT{sub e}/T{sub i}≲20, beyond which the instability is shown to scale with a higher power of ϕ{sub 1}, where Z is the ion charge number and T{sub e} (T{sub i}) is the electron (ion) thermal temperature. The threshold for instability is found to be smaller by an order of magnitude than linear theory estimates. Achieving a better understanding of the saturation of stimulated Brillouin scatter levels observed in laser-plasma interaction experiments is part of the motivation for this study.
PyDecay/GraphPhys: A Unified Language and Storage System for Particle Decay Process Descriptions
Dunietz, Jesse N.; /MIT /SLAC
2011-06-22
To ease the tasks of Monte Carlo (MC) simulation and event reconstruction (i.e. inferring particle-decay events from experimental data) for long-term BaBar data preservation and analysis, the following software components have been designed: a language ('GraphPhys') for specifying decay processes, common to both simulation and data analysis, allowing arbitrary parameters on particles, decays, and entire processes; an automated visualization tool to show graphically what decays have been specified; and a searchable database storage mechanism for decay specifications. Unlike HepML, a proposed XML standard for HEP metadata, the specification language is designed not for data interchange between computer systems, but rather for direct manipulation by human beings as well as computers. The components are interoperable: the information parsed from files in the specification language can easily be rendered as an image by the visualization package, and conversion between decay representations was implemented. Several proof-of-concept command-line tools were built based on this framework. Applications include building easier and more efficient interfaces to existing analysis tools for current projects (e.g. BaBar/BESII), providing a framework for analyses in future experimental settings (e.g. LHC/SuperB), and outreach programs that involve giving students access to BaBar data and analysis tools to give them a hands-on feel for scientific analysis.
Energy spectra of massive two-body decay products and mass measurement
Agashe, Kaustubh; Franceschini, Roberto; Hong, Sungwoo; Kim, Doojin
2016-04-26
Here, we have recently established a new method for measuring the mass of unstable particles produced at hadron colliders based on the analysis of the energy distribution of a massless product from their two-body decays. The central ingredient of our proposal is the remarkable result that, for an unpolarized decaying particle, the location of the peak in the energy distribution of the observed decay product is identical to the (fixed) value of the energy that this particle would have in the rest-frame of the decaying particle, which, in turn, is a simple function of the involved masses. In addition, wemore » utilized the property that this energy distribution is symmetric around the location of peak when energy is plotted on a logarithmic scale. The general strategy was demonstrated in several specific cases, including both beyond the standard model particles, as well as for the top quark. In the present work, we generalize this method to the case of a massive decay product from a two-body decay; this procedure is far from trivial because (in general) both the above-mentioned properties are no longer valid. Nonetheless, we propose a suitably modified parametrization of the energy distribution that was used successfully for the massless case, which can deal with the massive case as well. We test this parametrization on concrete examples of energy spectra of Z bosons from the decay of a heavier supersymmetric partner of top quark (stop) into a Z boson and a lighter stop. After establishing the accuracy of this parametrization, we study a realistic application for the same process, but now including dominant backgrounds and using foreseeable statistics at LHC14, in order to determine the performance of this method for an actual mass measurement. The upshot of our present and previous work is that, in spite of energy being a Lorentz-variant quantity, its distribution emerges as a powerful tool for mass measurement at hadron colliders.« less
Sensitivity of CUORE to Neutrinoless Double-Beta Decay (Journal...
Office of Scientific and Technical Information (OSTI)
Sensitivity of CUORE to Neutrinoless Double-Beta Decay Citation Details In-Document Search Title: Sensitivity of CUORE to Neutrinoless Double-Beta Decay In this paper, we study the...
Sensitivity of CUORE to Neutrinoless Double-Beta Decay (Journal...
Office of Scientific and Technical Information (OSTI)
Sensitivity of CUORE to Neutrinoless Double-Beta Decay Citation Details In-Document Search Title: Sensitivity of CUORE to Neutrinoless Double-Beta Decay You are accessing a...
Radioactive decay data tables (Technical Report) | SciTech Connect
Office of Scientific and Technical Information (OSTI)
Radioactive decay data tables Citation Details In-Document Search Title: Radioactive decay data tables You are accessing a document from the Department of Energy's (DOE) SciTech ...
Method of predicting mechanical properties of decayed wood
Kelley, Stephen S.
2003-07-15
A method for determining the mechanical properties of decayed wood that has been exposed to wood decay microorganisms, comprising: a) illuminating a surface of decayed wood that has been exposed to wood decay microorganisms with wavelengths from visible and near infrared (VIS-NIR) spectra; b) analyzing the surface of the decayed wood using a spectrometric method, the method generating a first spectral data of wavelengths in VIS-NIR spectra region; and c) using a multivariate analysis to predict mechanical properties of decayed wood by comparing the first spectral data with a calibration model, the calibration model comprising a second spectrometric method of spectral data of wavelengths in VIS-NIR spectra obtained from a reference decay wood, the second spectral data being correlated with a known mechanical property analytical result obtained from the reference decayed wood.
Micromechanism linear actuator with capillary force sealing
Sniegowski, Jeffry J.
1997-01-01
A class of micromachine linear actuators whose function is based on gas driven pistons in which capillary forces are used to seal the gas behind the piston. The capillary forces also increase the amount of force transmitted from the gas pressure to the piston. In a major subclass of such devices, the gas bubble is produced by thermal vaporization of a working fluid. Because of their dependence on capillary forces for sealing, such devices are only practical on the sub-mm size scale, but in that regime they produce very large force times distance (total work) values.
Neutrinoless double beta decay and future neutrino oscillation precision experiments
Choubey, Sandhya [Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Rodejohann, Werner [Physik-Department, Technische Universitaet Muenchen, James-Franck-Strasse, D-85748 Garching (Germany)
2005-08-01
We discuss to what extent future precision measurements of neutrino mixing observables will influence the information we can draw from a measurement of (or an improved limit on) neutrinoless double beta decay. Whereas the {delta}m{sup 2} corresponding to solar and atmospheric neutrino oscillations are expected to be known with good precision, the parameter {theta}{sub 12} will govern a large part of the uncertainty. We focus, in particular, on the possibility of distinguishing the neutrino mass hierarchies and on setting a limit on the neutrino mass. We give the largest allowed values of the neutrino masses which allow to distinguish the normal from the inverted hierarchy. All aspects are discussed as a function of the uncertainty stemming from the involved nuclear matrix elements. The implications of a vanishing, or extremely small, effective mass are also investigated. By giving a large list of possible neutrino mass matrices and their predictions for the observables, we finally explore how a measurement of (or an improved limit on) neutrinoless double beta decay can help to identify the neutrino mass matrix if more precise values of the relevant parameters are known.
Belos Block Linear Solvers Package
Energy Science and Technology Software Center (OSTI)
2004-03-01
Belos is an extensible and interoperable framework for large-scale, iterative methods for solving systems of linear equations with multiple right-hand sides. The motivation for this framework is to provide a generic interface to a collection of algorithms for solving large-scale linear systems. Belos is interoperable because both the matrix and vectors are considered to be opaque objects--only knowledge of the matrix and vectors via elementary operations is necessary. An implementation of Balos is accomplished viamore » the use of interfaces. One of the goals of Belos is to allow the user flexibility in specifying the data representation for the matrix and vectors and so leverage any existing software investment. The algorithms that will be included in package are Krylov-based linear solvers, like Block GMRES (Generalized Minimal RESidual) and Block CG (Conjugate-Gradient).« less
Linear Corrugating - Final Technical Report
Lloyd Chapman
2000-05-23
Linear Corrugating is a process for the manufacture of corrugated containers in which the flutes of the corrugated medium are oriented in the Machine Direction (MD) of the several layers of paper used. Conversely, in the conventional corrugating process the flutes are oriented at right angles to the MD in the Cross Machine Direction (CD). Paper is stronger in MD than in CD. Therefore, boxes made using the Linear Corrugating process are significantly stronger-in the prime strength criteria, Box Compression Test (BCT) than boxes made conventionally. This means that using Linear Corrugating boxes can be manufactured to BCT equaling conventional boxes but containing 30% less fiber. The corrugated container industry is a large part of the U.S. economy, producing over 40 million tons annually. For such a large industry, the potential savings of Linear Corrugating are enormous. The grant for this project covered three phases in the development of the Linear Corrugating process: (1) Production and evaluation of corrugated boxes on commercial equipment to verify that boxes so manufactured would have enhanced BCT as proposed in the application; (2) Production and evaluation of corrugated boxes made on laboratory equipment using combined board from (1) above but having dual manufactures joints (glue joints). This box manufacturing method (Dual Joint) is proposed to overcome box perimeter limitations of the Linear Corrugating process; (3) Design, Construction, Operation and Evaluation of an engineering prototype machine to form flutes in corrugating medium in the MD of the paper. This operation is the central requirement of the Linear Corrugating process. Items I and II were successfully completed, showing predicted BCT increases from the Linear Corrugated boxes and significant strength improvement in the Dual Joint boxes. The Former was constructed and operated successfully using kraft linerboard as the forming medium. It was found that tensile strength and stretch
Linear Fresnel Power Plant Illustration
With this concentrating solar power (CSP) graphic, flat or slightly curved mirrors mounted on trackers on the ground are configured to reflect sunlight onto a receiver tube fixed in space above these mirrors. A small parabolic mirror is sometimes added atop the receiver to further focus the sunlight. Linear CSP collectors capture the sun's energy with large mirrors that reflect and focus the sunlight onto a linear receiver tube. The receiver contains a fluid that is heated by the sunlight and then used to create superheated steam that spins a turbine that drives a generator to produce electricity.
CKM-suppressed top quark decays t{yields}s(d)+W in the standard model and beyond
Diaz-Cruz, J. L.; Gaitan-Lozano, R.; Castro, G. Lopez; Pagliarone, C. E.
2008-05-01
As it is well known, top quark decays are of particular interest as a means to test the standard model (SM) predictions, these include the dominant (t{yields}b+W), the Cabibbo-Kobayashi-Maskawa (CKM)-suppressed process t{yields}cWW, and the rare decays (t{yields}cV, cVV, c{phi}{sup 0}, bWZ). As all of them are highly suppressed, they become an excellent window to probe the predictions of theories beyond the SM. In this paper, we evaluate the corrections from new physics to the CKM-suppressed SM top quark decay t{yields}q+W(q=d,s), both within an effective model with right-handed currents and for the minimal SUSY extension of the SM. We also discuss the perspectives to probe those predictions at the International Linear Collider.
A Search for Direct CP Violation in Two-Body Cabibbo-Suppressed Decays of Neutral Charmed Mesons
Flacco, Christian Julienne
2007-11-12
Presented are the results of a search for direct CP violation in Cabibbo-suppressed decays of D{sup 0} to two charged daughters. The analysis described was performed on {approx}230 fb{sup -1} of the BABAR data sample, recorded at the Stanford Linear Accelerator Center and using the PEP-II electron storage rings. We measure CP asymmetries for decay to the KK and {pi}{pi} final states, as well as for the branching ratio, and develop a new technique for tagging-efficiency correction using the Cabibbo-favored K{pi} final state. We find some evidence for CP violation in decays to the KK final state and results that suggest CP violation in the {pi}{pi} final state as well.
Cold Positrons from Decaying Dark Matter
Boubekeur, Lotfi; Dodelson, Scott; Vives, Oscar
2012-11-01
Many models of dark matter contain more than one new particle beyond those in the Standard Model. Often heavier particles decay into the lightest dark matter particle as the Universe evolves. Here we explore the possibilities that arise if one of the products in a (Heavy Particle) $\\rightarrow$ (Dark Matter) decay is a positron, and the lifetime is shorter than the age of the Universe. The positrons cool down by scattering off the cosmic microwave background and eventually annihilate when they fall into Galactic potential wells. The resulting 511 keV flux not only places constraints on this class of models but might even be consistent with that observed by the INTEGRAL satellite.
Weissman, L.; Lisetskiy, A.F.; Arndt, O.; Dillmann, I.; Hallmann, O.; Kratz, K.L.; Pfeiffer, B.; Bergmann, U.; Cederkall, J.; Fraile, L.; Koester, U.; Franchoo, S.; Gaudefroy, L.; Sorlin, O.; Tabor, S.
2004-11-01
A pure neutron-rich {sup 26}Ne beam was obtained at the ISOLDE facility using isobaric selectivity. This was achieved by a combination of a plasma ion source with a cooled transfer line and subsequent mass separation. The high quality of the beam and good statistics allowed us to obtain new experimental information on the {sup 26}Ne {beta}-decay properties and resolve a contradiction between earlier experimental data and prediction of shell-model calculations.
Polarization observables from the photoproduction of omega-mesons using linearly polarized photons
D. Martinez, P.L. Cole, CLAS Collaboration
2012-04-01
We report on the photon beam asymmetry, {Sigma}, of the {omega} meson decaying into {pi}{sup +}, {pi}{sup -}, {pi}{sup 0} using a beam of linearly polarized photons in the photon energy region of E{sub {gamma}} = 1.9 GeV. These preliminary results are from the summer 2005 g8b dataset, which were collected with the CLAS detector in Hall B of Jefferson Lab.
Linear electric field mass spectrometry
McComas, D.J.; Nordholt, J.E.
1992-12-01
A mass spectrometer and methods for mass spectrometry are described. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field. 8 figs.
Linear electric field mass spectrometry
McComas, David J.; Nordholt, Jane E.
1992-01-01
A mass spectrometer and methods for mass spectrometry. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field.
D meson hadronic decays at CLEO-c
Yang, Fan; /Fermilab
2011-01-01
The recent CLEO-c results on hadronic decays of D and D{sub s} mesons are presented. First the absolute branching fractions for D and D{sub s} mesons using a double tag technique are discussed, then are the Cabibbo suppressed decays and doubly Cabibbo suppressed decays. Finally, I present the inclusive and rare decay modes and other measurements from CLEO-c. These decays illuminate a wide range of physics. A brief theoretical introduction is given before the corresponding discussion on measurement.
Measurements of the kaon content in tau decays
Ronan, M.T. )
1992-02-01
Results on measurements of the kaon content in one-prong and three-prong [tau] decays are presented for data taken by the TPC/2[gamma] detector at PEP. Using a self-consistent procedure to measure exclusive and inclusive decays, the one-prong analysis extends previous work to kaon decay modes. Three-prong results [ital K][pi][pi], [ital K][pi] and [ital KKK] decay modes provide improved branching ratios and a first look at strange axial-vector couplings in [tau] decays.
The nuclear matrix elements for neutrinoless double beta decay
Simkovic, Fedor [Department of Nuclear Physics and Biophysics, Comenius University, Mlynska dolina, SK-84248 Bratislava (Slovakia)
2007-10-12
The status of calculation of the neutrinoless double beta decay (0{nu}{beta}{beta}-decay) nuclear matrix elements (NME's) is reviewed. The spread of published values of NME's is discussed. The main attention is paid to the recent progress achieved in the evaluation of the 0{nu}{beta}{beta}-decay NME's in the framework of the quasiparticle random phase approximation (QRPA). The obtained results are compared with those of the nuclear shell model. The problem of reliable determination of the 0{nu}{beta}{beta}-decay NME's is addressed. The uncertainty in NME's are analyzed and further progress in calculation of the 0{nu}{beta}{beta}-decay NME's is outlined.
Thermal effects and sudden decay approximation in the curvaton scenario
Kitajima, Naoya; Takesako, Tomohiro; Yokoyama, Shuichiro; Langlois, David; Takahashi, Tomo E-mail: langlois@apc.univ-paris7.fr E-mail: takesako@icrr.u-tokyo.ac.jp
2014-10-01
We study the impact of a temperature-dependent curvaton decay rate on the primordial curvature perturbation generated in the curvaton scenario. Using the familiar sudden decay approximation, we obtain an analytical expression for the curvature perturbation after the decay of the curvaton. We then investigate numerically the evolution of the background and of the perturbations during the decay. We first show that the instantaneous transfer coefficient, related to the curvaton energy fraction at the decay, can be extended into a more general parameter, which depends on the net transfer of the curvaton energy into radiation energy or, equivalently, on the total entropy ratio after the complete curvaton decay. We then compute the curvature perturbation and compare this result with the sudden decay approximation prediction.
Calculated secondary yields for proton broadband using DECAY TURTLE
Sondgeroth, A.
1995-02-01
The calculations for the yields were done by Al Sondgeroth and Anthony Malensek. The authors used the DECAY deck called PBSEC{_}E.DAT from the CMS DECKS library. After obtaining the run modes and calibration modes from the liaison physicist, they made individual decay runs, using DECAY TURTLE from the CMS libraries and a production spectrum subroutine which was modified by Anthony, for each particle and decay mode for all particle types coming out of the target box. Results were weighted according to branching ratios for particles with more than one decay mode. The production spectra were produced assuming beryllium as the target. The optional deuterium target available to broadband will produce slightly higher yields. It should be noted that they did not include pion yields from klong decays because they could not simulate three body decays. Pions from klongs would add a very small fraction to the total yield.
International Linear Collider Technical Design Report - Volume...
Office of Scientific and Technical Information (OSTI)
International Linear Collider Technical Design Report - Volume 2: Physics Citation Details In-Document Search Title: International Linear Collider Technical Design Report - Volume ...
Borges, H. A.; Carneiro, S.; Fabris, J. C.
2008-12-15
We extend the results of a previous paper where a model of interacting dark energy, with a cosmological term decaying linearly with the Hubble parameter, is tested against the observed mass power spectrum. In spite of the agreement with observations of type Ia supernovas, baryonic acoustic oscillations, and the cosmic microwave background, we had shown previously that no good concordance is achieved if we include the mass power spectrum. However, our analysis was based on the ad hoc assumption that the interacting cosmological term is strictly homogeneous. Now we perform a more complete analysis, by perturbing such a term. Although our conclusions are still based on a particular, scale-invariant choice of the primordial spectrum of dark energy perturbations, we show that a cosmological term decaying linearly with the Hubble parameter is indeed disfavored as compared to the standard model.
Thiessen, Douglas Michael; /British Columbia U.
2005-08-30
This thesis presents a measurement of the branching fraction for the exclusive semileptonic decay {bar B}{sup 0} {yields} D*{sup +}{mu}{sup -}{nu}{sub {mu}}. This decay is essentially the decay of a b quark to a c quark inside the meson with the release of a muon and neutrino, and it provides a very clean signal for measuring various B meson decay properties. the data for this measurement consist of 22.3 million B{bar B} pairs collected by the BABAR detector at the Stanford Linear Accelerator Center in 1999-2000. The branching fraction is measured to be {Beta}({bar B}{sup 0} {yields} D*{sup +}{mu}{sup -}{bar {nu}}{sub {mu}}) = [4.72 {+-} 0.10 (data stat.) {+-} 0.06 (MC stat.) {+-} 0.20 (syst.) {+-} 0.17 (other {Beta})]%.
On Decays of B Mesons to a Strange Meson and an Eta or Eta' Meson at Babar
Hirschauer, James Francis
2009-01-01
We describe studies of the decays of B mesons to final states ηK*(892), ηK*_{0}(S-wave), ηK*_{2}(1430), and η'K based on data collected with the BABAR detector at the PEP-II asymmetric-energy e^{+}e^{-} collier at the Stanford Linear Accelerator Center. We measure branching fractions and charge asymmetries for the decays B → ηK*, where K* indicates a spin 0, 1, or 2 Kπ system, making first observations of decays to final states ηK^{0*}_{0}(S-wave), ηK^{+*}_{0} (S-wave), and ηK^{0*}_{2}(1430). We measure the time-dependent CP-violation parameters S and C for the decays B^{0} → η'K^{0}, observing CP violation in a charmless B decay with 5σ significance considering both statistical and systematic uncertainties.
Linear Fixed-Field Multi-Pass Arcs for Recirculating Linear Accelerators
V.S. Morozov, S.A. Bogacz, Y.R. Roblin, K.B. Beard
2012-06-01
Recirculating Linear Accelerators (RLA's) provide a compact and efficient way of accelerating particle beams to medium and high energies by reusing the same linac for multiple passes. In the conventional scheme, after each pass, the different energy beams coming out of the linac are separated and directed into appropriate arcs for recirculation, with each pass requiring a separate fixed-energy arc. In this paper we present a concept of an RLA return arc based on linear combined-function magnets, in which two and potentially more consecutive passes with very different energies are transported through the same string of magnets. By adjusting the dipole and quadrupole components of the constituting linear combined-function magnets, the arc is designed to be achromatic and to have zero initial and final reference orbit offsets for all transported beam energies. We demonstrate the concept by developing a design for a droplet-shaped return arc for a dog-bone RLA capable of transporting two beam passes with momenta different by a factor of two. We present the results of tracking simulations of the two passes and lay out the path to end-to-end design and simulation of a complete dog-bone RLA.
Cast dielectric composite linear accelerator
Sanders, David M.; Sampayan, Stephen; Slenes, Kirk; Stoller, H. M.
2009-11-10
A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.
Segmented rail linear induction motor
Cowan, M. Jr.; Marder, B.M.
1996-09-03
A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces. 6 figs.
Segmented rail linear induction motor
Cowan, Jr., Maynard; Marder, Barry M.
1996-01-01
A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces.
Cunha, J. Adam M.
2008-01-16
The authors report on a search for the decay B{sup {+-}} {yields} D{sub s}{sup (*){+-}} {phi} using 212.2 fb{sup -1} of data collected with the BABAR detector at the PEP-II B Factory at the Stanford Linear Accelerator Center between 1999 and 2004. This sample of 234 x 10{sup 6} e{sup +}e{sup -} {yields} {Upsilon}(4S) {yields} B{bar B} events yields no significant signal. They report the Bayesian upper limits {Beta}(B{sup {+-}} {yields} D{sub s}{sup {+-}} {phi}) x {Beta}(D{sub s}{sup {+-}} {yields} {phi}{pi}{sup {+-}}) < 8.6 x 10{sup -8} and {Beta}(B{sup {+-}} {yields} D*{sub s}{sup {+-}}{phi}) x {Beta}(D{sub s}{sup {+-}} {yields} {phi}{pi}{sup {+-}}) < 5.4 x 10{sup -7} at the 90% C.L. Using the latest measurement of {Beta}(D{sub s}{sup {+-}} {yields} {phi}{pi}{sup {+-}}), they report: {Beta}(B{sup {+-}} {yields} D{sub s}{sup {+-}}{phi}) < 1.8 x 10{sup -6} and {Beta}(B{sup {+-}} {yields} D*{sub s}{sup {+-}}{phi}) < 1.1 x 10{sup -5} at the 90% C.L.
Linearity Testing of Photovoltaic Cells
Emery, K.; Winter, S.; Pinegar, S.; Nalley, D.
2006-01-01
Photovoltaic devices are rated in terms of their peak power with respect to a specific spectrum, total irradiance, and temperature. To rate photovoltaic devices, a reference detector is required whose response is linear with total irradiance. This paper describes a procedure to determine the linearity of the short-circuit current (I{sub sc}) versus the total irradiance (E{sub tot}) by illuminating a reference cell with two lamps. A device is linear if the current measured with both lamps illuminating the cell is the same as the sum of the currents with each lamp illuminating the cell. The two-lamp method is insensitive to the light spectra or spatial nonuniformity changing with irradiance. The two-lamp method is rapid, easy to implement, and does not require operator intervention to change the irradiances. The presence of room light only limits the lowest irradiance that can be evaluated. Unlike other methods, the two-lamp method does not allow the current to be corrected for nonlinear effects.
Fission-product-decay characteristics. Master's thesis
Millage, K.K.
1989-03-01
This theses determined fission-product decay characteristics , including the total activity, the gamma-ray emission rate (GER) and gamma-ray energy spectra. The activity and GER decay were compared to Way and Wigner's t(exp(-1.2)) approximation, and the effects the spectra, activity, and GER have on the Source Normalization Constant (K) were examined. Most of the fission-product data were obtained from DKPOWR, and were compared with data obtained from ORIGIN2. Since the gamma rays are of primary concern in fallout studies, the GER is used instead of activity. The ratio of GER to activity changes significantly with time. Results of this study calculate a GER of 590 x 10/sup 16/ gamma rays/second per kT of fission yield from U-235 fuel and a K of 7059 R/Hr/(kT/sq.km.). The calculation of K includes the contribution from scattered photons. The GER result is 11% higher than reference values, while the K is within 2% of the current value in Glasstone and Dolan's The Effects of Nuclear Weapons. The Ks for Pu-239 and U-238 were within 5% of the U-235 results. The wax-wigners t(exp(-1.2)) approximation differs from time dependent GER and K up to 85% for times less than 6 months. The approximation is not valid for the GER or K at times greater than 6 months. The approximation is within about 45%, for the activity from fission-product decay to at least 5 years. A more accurate measure of exposure requires a numerical integration of the time dependent GER and Source Normalization Constant.
Antideuterons from decaying gravitino dark matter
Delahaye, Timur; Grefe, Michael
2015-07-08
We study the possibility of improving the constraints on the lifetime of gravitino dark matter in scenarios with bilinear R-parity violation by estimating the amount of cosmic-ray antideuterons that can be produced in gravitino decays. Taking into account all different sources of theoretical uncertainties, we find that the margin of improvement beyond the limits already set by cosmic-ray antiproton data are quite narrow and unachievable for the next generation of experiments. However, we also identify more promising energy ranges for future experiments.
Gomez Dumm, D.; Pich, A.; Portoles, J.
2006-01-12
{tau} decays into hadrons foresee the study of the hadronization of vector and axial-vector QCD currents, yielding relevant information on the dynamics of the resonances entering into the processes. We analyse {tau} {yields} {pi}{pi}{pi}{nu}{tau} decays within the framework of the Resonance Chiral Theory, comparing this theoretical scheme with the experimental data, namely ALEPH spectral function and branching ratio. Hence we get values for the mass and on-shell width of the a 1 (1260) resonance, and provide the structure functions that have been measured by OPAL and CLEO-II.
E.W Kuns
2002-10-18
This dissertation presents a measurement of the tau charge asymmetry in events where the taus are produced by W decays. This charge asymmetry appears as different rapidity distributions for positive and negative taus. Two competing effects generate tau charge asymmetry. The production mechanism for the W gauge boson generates a charge asymmetry which is a function of the ratio of parton distribution functions, d(x)=u(x), measured at x {approx} M{sub W}/{radical}s. This is the dominant effect for tau charge asymmetry at small rapidity. At higher rapidity, however, the competing charge asymmetry from parity violation in W decay to taus becomes dominant. This tau asymmetry measurement is consistent with the Standard Model with a x{sup 2} per degree of freedom equal to 2.5 for 4 degrees of freedom when the asymmetry measurement is folded about y = 0, taking advantage of the CP symmetry of the underlying physics, and 8.9 for 8 degrees of freedom when it is not. This measurement introduces some methods and variables of interest to future analyses using hadronic decay modes of taus. This work was done using the CDF detector in {bar p}p collisions at {radical} = 1.8 TeV at Fermilab's Tevatron accelerator.
Linear Thermite Charge - Energy Innovation Portal
U.S. Department of Energy (DOE) all webpages (Extended Search)
Linear Thermite Charge Battelle Memorial Institute Contact BMI About This Technology Publications: PDF Document Publication Linear Thermite Charge Picture (40 KB) PDF Document Publication Linear Thermite Charge Patent (207 KB) Technology Marketing Summary The Linear Thermite Charge (LTC) is designed to rapidly cut through concrete and steel structural components by using extremely high temperature thermite reactions jetted through a linear nozzle. Description Broadly, the invention provides for
CALiPER Snapshot Linear Lamps (TLEDs)
BUILDING TECHNOLOGIES OFFICE Snapshot Linear Lamps (TLEDs) Linear fluorescent lamps-and the "troffers" in which they are often used-are a staple of ambient lighting in offices, classrooms, and other types of commercial spaces. They are energy-efficient, long-lived, and relatively inexpensive. Linear LED lamps, often called TLEDs, are an alternative to linear fluorescent lamps and are mainly used in retrofit situations. Typically drawing about 60% of the power of linear fluorescent
Inverse neutrinoless double beta decay revisited: Neutrinos, Higgs triplets, and a muon collider
Rodejohann, Werner [Max-Planck-Institut fuer Kernphysik, Postfach 103980, D-69029 Heidelberg (Germany)
2010-06-01
We revisit the process of inverse neutrinoless double beta decay (e{sup -}e{sup -{yields}}W{sup -}W{sup -}) at future linear colliders. The cases of Majorana neutrino and Higgs triplet exchange are considered. We also discuss the processes e{sup -{mu}-{yields}}W{sup -}W{sup -} and {mu}{sup -{mu}-{yields}}W{sup -}W{sup -}, which are motivated by the possibility of muon colliders. For heavy neutrino exchange, we show that masses up to 10{sup 6} (10{sup 5}) GeV could be probed for ee and e{mu} machines, respectively. The stringent limits for mixing of heavy neutrinos with muons render {mu}{sup -{mu}-{yields}}W{sup -}W{sup -} less promising, even though this process is not constrained by limits from neutrinoless double beta decay. If Higgs triplets are responsible for inverse neutrinoless double beta decay, observable signals are only possible if a very narrow resonance is met. We also consider unitarity aspects of the process in case both Higgs triplets and neutrinos are exchanged. An exact seesaw relation connecting low energy data with heavy neutrino and triplet parameters is found.
Effect of quark sector minimal flavor violation on neutrinoless double beta decay
Dudley, Brian; Kolda, Christopher [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)
2009-01-01
The question of whether neutrino masses are Dirac or Majorana is one of the most important, and most difficult, questions remaining in the neutrino sector. Searches for neutrinoless double {beta} decay may help to resolve this question, but are also sensitive to new, higher-dimension {delta}L=2 operators. In this paper we place two phenomenological constraints on these operators at dimension d{<=}11. First, we require that the operators obey the quark flavor symmetries of the standard model, with any violation of the symmetries being due to Yukawa interactions, a scheme known as minimal flavor violation. Second, we require that the operators which generate neutrinoless double {beta} decay, and any operators related by the flavor symmetries, do not induce neutrino masses above the experimental and astrophysical limits. We find that these requirements severely constrain the operators which can violate lepton number, such that most can no longer contribute to neutrinoless double {beta} decay at observable rates. It is noteworthy that quark flavor symmetries can play such a strong role in constraining new leptonic physics, even when that physics is not quark flavor changing. Those few operators that can mimic a Majorana neutrino mass then appear with cutoffs below a TeV, and represent new physics which could be directly probed at the LHC or a future linear collider.
A search for jet handedness in hadronic Z{sup 0} decays
Hasegawa, Yoji
1995-03-01
Transport of polarization through hadronization process is one of the fundamental interest in Quantum Chromodynamics which is a theory of strong interactions. In the low energy region where the hadronization occurs, QCD calculations are difficult, therefore at present the transport can be investigated experimentally. In this study the authors have searched for signatures of polarization of quarks and antiquarks in hadronic jets from Z{sup 0} {yields} q{bar q} decays. The polarization of quarks and antiquark produced by Z{sup 0} decays are predicted by the Standard Model of elementary particle physics. The authors defined several quantities depending on {open_quotes}jet handedness{close_quotes} methods and studied the correlation between the predicted polarization and the quantities. The signal was estimated by analyzing power which represents degree of the polarization transport through the hadronization process. The Z{sup 0} decays were measured by SLC Large Detector and the polarized electron beam provided by SLAC Linear Collider was useful for this study. The data from the 1993 run showed no signature of the transport of quark and antiquark polarization. Upper limits on magnitude of the analyzing power were set in the range 0.05-0.15 depending on the methods.
Inclusive radiative J/{psi} decays
Besson, D.; Pedlar, T. K.; Cronin-Hennessy, D.; Gao, K. Y.; Hietala, J.; Kubota, Y.; Klein, T.; Lang, B. W.; Poling, R.; Scott, A. W.; Zweber, P.; Dobbs, S.; Metreveli, Z.; Seth, K. K.; Tomaradze, A.; Libby, J.; Powell, A.; Wilkinson, G.; Ecklund, K. M.; Love, W.
2008-08-01
Using data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct-photon momentum spectrum in the decay J/{psi}(1S){yields}{gamma}gg, via the ''tagged'' process: e{sup +}e{sup -}{yields}{psi}(2S); {psi}(2S){yields}J/{psi}{pi}{sup +}{pi}{sup -}; J/{psi}{yields}{gamma}+X. Including contributions from two-body radiative decay processes, we find the ratio of the inclusive direct-photon branching fraction to that of the dominant three-gluon branching fraction [R{sub {gamma}}=B(gg{gamma})/B(ggg)] to be R{sub {gamma}}=0.137{+-}0.001{+-}0.016{+-}0.004, where the errors shown are statistical, systematic, and the model-dependent uncertainty related to the extrapolation to zero photon energy. The shape of the scaled photon energy spectrum in J/{psi}{yields}gg{gamma} is observed to be very similar to that of {upsilon}{yields}gg{gamma}. The R{sub {gamma}} value obtained is roughly consistent with that expected by a simple quark-charge scaling [R{sub {gamma}}{approx}(q{sub c}/q{sub b}){sup 2}] of the value determined at the {upsilon}(1S), but somewhat higher than the value expected from the running of the strong coupling constant.
Linear dimensions and volumes of human lungs
Hickman, David P.
2012-03-30
TOTAL LUNG Capacity is defined as “the inspiratory capacity plus the functional residual capacity; the volume of air contained in the lungs at the end of a maximal inspiration; also equals vital capacity plus residual volume” (from MediLexicon.com). Within the Results and Discussion section of their April 2012 Health Physics paper, Kramer et al. briefly noted that the lungs of their experimental subjects were “not fully inflated.” By definition and failure to obtain maximal inspiration, Kramer et. al. did not measure Total Lung Capacity (TLC). The TLC equation generated from this work will tend to underestimate TLC and does notmore » improve or update total lung capacity data provided by ICRP and others. Likewise, the five linear measurements performed by Kramer et. al. are only representative of the conditions of the measurement (i.e., not at-rest volume, but not fully inflated either). While there was significant work performed and the data are interesting, the data does not represent a maximal situation, a minimal situation, or an at-rest situation. Moreover, while interesting, the linear data generated by this study is limited by the conditions of the experiment and may not be fully comparative with other lung or inspiratory parameters, measures, or physical dimensions.« less
Nonferromagnetic linear variable differential transformer
Ellis, James F.; Walstrom, Peter L.
1977-06-14
A nonferromagnetic linear variable differential transformer for accurately measuring mechanical displacements in the presence of high magnetic fields is provided. The device utilizes a movable primary coil inside a fixed secondary coil that consists of two series-opposed windings. Operation is such that the secondary output voltage is maintained in phase (depending on polarity) with the primary voltage. The transducer is well-suited to long cable runs and is useful for measuring small displacements in the presence of high or alternating magnetic fields.
Acoustic emission linear pulse holography
Collins, H. Dale; Busse, Lawrence J.; Lemon, Douglas K.
1985-01-01
Defects in a structure are imaged as they propagate, using their emitted acoustic energy as a monitored source. Short bursts of acoustic energy propagate through the structure to a discrete element receiver array. A reference timing transducer located between the array and the inspection zone initiates a series of time-of-flight measurements. A resulting series of time-of-flight measurements are then treated as aperture data and are transferred to a computer for reconstruction of a synthetic linear holographic image. The images can be displayed and stored as a record of defect growth.
Neutron Interactions in the CUORE Neutrinoless Double Beta Decay Experiment
Office of Scientific and Technical Information (OSTI)
(Thesis/Dissertation) | SciTech Connect Thesis/Dissertation: Neutron Interactions in the CUORE Neutrinoless Double Beta Decay Experiment Citation Details In-Document Search Title: Neutron Interactions in the CUORE Neutrinoless Double Beta Decay Experiment Neutrinoless double beta decay (0vDBD) is a lepton-number violating process that can occur only for a massive Majorana neutrino. The search for 0vDBD is currently the only practical experimental way to determine whether neutrinos are
No-neutrino double beta decay: more than one neutrino
Rosen, S.P.
1983-01-01
Interference effects between light and heavy Majorana neutrinos in the amplitude for no-neutrino double beta decay are discussed. The effects include an upper bound on the heavy neutrino mass, and an A dependence for the effective mass extracted from double beta decay. Thus the search for the no-neutrino decay mode should be pursued in several nuclei, and particularly in Ca/sup 48/, where the effective mass may be quite large.
Penguin and rare decays in BaBar
Akar, Simon
2015-04-29
We present recent results from the BABAR Collaboration on radiative decays. These include searches for new physics via measurements of several observables such as the time- dependent CP asymmetry in B^{0} ? K^{0}_{S}?^{} ?^{+}? exclusive decays, as well as direct CP asymmetries and branching fractions in B ? X_{s}? and B ? X_{s}?^{+}?^{} inclusive decays.
Neutrinoless double beta decay search with the NEMO 3 experiment
Nasteva, Irina [Particle Physics Group, School of Physics and Astronomy, University of Manchester, Manchester, M13 9PL (United Kingdom)
2008-11-23
The NEMO 3 experiment searches for neutrinoless double beta decay and makes precision measurements of two-neutrino double beta decay in seven isotopes. The latest two-neutrino half-life results are presented, together with the limits on neutrinoless half-lives and the corresponding effective Majorana neutrino masses. Also given are the limits obtained on neutrinoless double beta decay mediated by R{sub p}-violating SUSY, right-hand currents and different Majoron emission modes.
Shortcuts to adiabaticity from linear response theory
Acconcia, Thiago V.; Bonança, Marcus V. S.; Deffner, Sebastian
2015-10-23
A shortcut to adiabaticity is a finite-time process that produces the same final state as would result from infinitely slow driving. We show that such shortcuts can be found for weak perturbations from linear response theory. Moreover, with the help of phenomenological response functions, a simple expression for the excess work is found—quantifying the nonequilibrium excitations. For two specific examples, i.e., the quantum parametric oscillator and the spin 1/2 in a time-dependent magnetic field, we show that finite-time zeros of the excess work indicate the existence of shortcuts. We finally propose a degenerate family of protocols, which facilitates shortcuts to adiabaticity for specific and very short driving times.
TLD linearity vs. beam energy and modality
Troncalli, Andrew J.; Chapman, Jane
2002-12-31
Thermoluminescent dosimetry (TLD) is considered to be a valuable dosimetric tool in determining patient dose. Lithium fluoride doped with magnesium and titanium (TLD-100) is widely used, as it does not display widely divergent energy dependence. For many years, we have known that TLD-100 shows supralinearity to dose. In a radiotherapy clinic, there are multiple energies and modality beams. This work investigates whether individual linearity corrections must be used for each beam or whether a single correction can be applied to all beams. The response of TLD as a function of dose was measured from 25 cGy to 1000 cGy on both electrons and photons from 6 to 18 MeV. This work shows that, within our measurement uncertainty, TLD-100 exhibits supralinearity at all megavoltage energies and modalities.
Shortcuts to adiabaticity from linear response theory
Acconcia, Thiago V.; Bonança, Marcus V. S.; Deffner, Sebastian
2015-10-23
A shortcut to adiabaticity is a finite-time process that produces the same final state as would result from infinitely slow driving. We show that such shortcuts can be found for weak perturbations from linear response theory. Moreover, with the help of phenomenological response functions, a simple expression for the excess work is found—quantifying the nonequilibrium excitations. For two specific examples, i.e., the quantum parametric oscillator and the spin 1/2 in a time-dependent magnetic field, we show that finite-time zeros of the excess work indicate the existence of shortcuts. We finally propose a degenerate family of protocols, which facilitates shortcuts tomore » adiabaticity for specific and very short driving times.« less
Mass measurement using energy spectra in three-body decays
Agashe, Kaustubh; Franceschini, Roberto; Kim, Doojin; Wardlow, Kyle
2016-05-24
In previous works we have demonstrated how the energy distribution of massless decay products in two body decays can be used to measure the mass of decaying particles. In this study, we show how such results can be generalized to the case of multi-body decays. The key ideas that allow us to deal with multi-body final states are an extension of our previous results to the case of massive decay products and the factorization of the multi-body phase space. The mass measurement strategy that we propose is distinct from alternative methods because it does not require an accurate reconstruction ofmore » the entire event, as it does not involve, for instance, the missing transverse momentum, but rather requires measuring only the visible decay products of the decay of interest. To demonstrate the general strategy, we study a supersymmetric model wherein pair-produced gluinos each decay to a stable neutralino and a bottom quark-antiquark pair via an off -shell bottom squark. The combinatorial background stemming from the indistinguishable visible final states on both decay sides can be treated by an “event mixing” technique, the performance of which is discussed in detail. In conclusion, taking into account dominant backgrounds, we are able to show that the mass of the gluino and, in favorable cases, that of the neutralino can be determined by this mass measurement strategy.« less
Radiative J/psi decays and the pseudoscalar puzzle
Wermes, N.
1985-07-01
Recent results on radiative decays of the J/PSI, obtained by the SPEAR detectors Mark III and Crystal Ball and the DCI detector DM2 at Orsay, are presented. The status of the glueball candidates theta(1690), iota(1460), and xi(220), and the decays J/PHI ..-->.. ..gamma.. Vector Vector are reviewed. A coupled channel analysis of iota(1460) decays to K anti K..pi.., rho rho, ..omega omega.., and ..gamma..rho is presented which may help to understand the pseudoscalar sector in radiative J/PHI decays. 42 refs., 16 figs.
Neutron Beta Decay as a Probe of Weak Interactions (Conference...
Office of Scientific and Technical Information (OSTI)
Citation Details In-Document Search Title: Neutron Beta Decay as a Probe of Weak Interactions Authors: Saunders, Alexander 1 + Show Author Affiliations Los Alamos National ...
Annihilation diagrams in two-body nonleptonic decays of charmed...
Office of Scientific and Technical Information (OSTI)
Subject: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHARMED MESONS; WEAK HADRONIC DECAY; ANNIHILATION; FEYNMAN DIAGRAM; TWO-BODY PROBLEM; AXIAL VECTOR MESONS; KOBAYASHI-MASKAWA ...
Lepton flavor violation in Higgs boson decays under the rare...
Office of Scientific and Technical Information (OSTI)
We show that a search for the LFV decays phisup 0yieldstausup +-musup +- (tausup +-esup +-) of neutral Higgs bosons (phisup 0h,H and A) at future ...
Searches for Leptonic B Decays at BaBar
Nelson, Silke; /SLAC
2012-04-25
Measurements of the branching fractions of purely leptonic decays of B-mesons translate into constraints in the plane of the charged Higgs mass versus tan {beta} which are relatively insensitive to the particular theoretical model. Using the full BABAR dataset of 450 million B-decays we search for these decays. No significant signal is found in the decays into electrons or muons and we set upper limits on the branching fractions of the order of a 10{sup -6} at 90% confidence level. We measure the branching fraction of B {yields} {tau}{mu} to be (1.7 {+-} 0.6) x 10{sup -4}.
Exploring the Neutrinoless Double Beta Decay in the Inverted...
Office of Scientific and Technical Information (OSTI)
Neutrinoless double beta decay (0) is one of the most sensitive probes for physics beyond the Standard Model, providing unique information on the nature of neutrinos. In this ...
Neutron Interactions in the CUORE Neutrinoless Double Beta Decay...
Office of Scientific and Technical Information (OSTI)
Interactions in the CUORE Neutrinoless Double Beta Decay Experiment Dolinski, M J 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS;...
Spectroscopy and Decay of $B$ Hadrons at the Tevatron
Paulini, Manfred
2007-02-01
The authors review recent results on heavy quark physics focusing on Run II measurements of B hadron spectroscopy and decay at the Tevatron. A wealth of new B physics measurements from CDF and D0 has been available. These include the spectroscopy of excited B states (B**, B**{sub s}) and the observation of the {Sigma}{sub b} baryon. The discussion of the decays of B hadrons and measurements of branching fractions focuses on charmless two-body decays of B {yields} h{sup +}h{sup -}. They report several new B{sub s}{sup 0} and {Lambda}{sub b}{sup 0} decay channels.
What can we learn from neutrinoless double beta decay experiments...
Office of Scientific and Technical Information (OSTI)
What can we learn from neutrinoless double beta decay experiments? Citation Details ... Country of Publication: United States Language: English Subject: 72 nucleus, semileptonic ...
Search for massive WH resonances decaying into the $$\\ell \
Khachatryan, Vardan
2016-04-28
In this study, a search for a massive resonancemore » $${\\mathrm{W}^{\\prime }}$$ decaying into a W and a Higgs boson in the $$\\ell \
Tunneling control using classical non-linear oscillator
Kar, Susmita; Bhattacharyya, S. P.
2014-04-24
A quantum particle is placed in symmetric double well potential which is coupled to a classical non-linear oscillator via a coupling function. With different spatial symmetry of the coupling and under various controlling fashions, the tunneling of the quantum particle can be enhanced or suppressed, or totally destroyed.
Translation and integration of numerical atomic orbitals in linear molecules
Heinäsmäki, Sami
2014-02-14
We present algorithms for translation and integration of atomic orbitals for LCAO calculations in linear molecules. The method applies to arbitrary radial functions given on a numerical mesh. The algorithms are based on pseudospectral differentiation matrices in two dimensions and the corresponding two-dimensional Gaussian quadratures. As a result, multicenter overlap and Coulomb integrals can be evaluated effectively.
Leptonic Decays of the Charged B Meson
Corwin, Luke A.; /Ohio State U.; ,
2010-06-11
The authors present a search for the decay B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}} ({ell} = {tau}, {mu}, or e) in (458.9 {+-} 5.1) x 10{sup 6} {Upsilon}(4S) decays recorded with the BABAR detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed exclusive semi-leptonic B decay (B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}X) is selected, and in the recoil a search for B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}} signal is performed. The {tau} is identified in the following channels: {tau}{sup +} {yields} e{sup +}{nu}{sub e}{bar {nu}}{sub {tau}}, {tau}{sup +} {yields} {mu}{sup +}{nu}{sub {mu}}{bar {nu}}{sub {tau}}, {tau}{sup +} {yields} {pi}{sup +}{bar {nu}}{sub {tau}}, and {tau}{sup +} {yields} {pi}{sup +}{pi}{sup 0}{bar {nu}}{sub {tau}}. The analysis strategy and the statistical procedure is set up for branching fraction extraction or upper limit determination. They determine from the dataset a preliminary measurement of {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) = (1.8 {+-} 0.8 {+-} 0.1) x 10{sup -4}, which excludes zero at 2.4{sigma}, and f{sub B} = 255 {+-} 58 MeV. Combination with the hadronically tagged measurement yields {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) = (1.8 {+-} 0.6) x 10{sup -4}. They also set preliminary limits on the branching fractions at {Beta}(B{sup +} {yields} e{sup +}{nu}{sub e}) < 7.7 x 10{sup -6} (90% C.L.), {Beta}(B{sup +} {yields} {mu}{sup +}{nu}{sub {mu}}) < 11 x 10{sup -6} (90% C.L.), and {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) < 3.2 x 10{sup -4} (90% C.L.).
Reticle stage based linear dosimeter
Berger, Kurt W.
2007-03-27
A detector to measure EUV intensity employs a linear array of photodiodes. The detector is particularly suited for photolithography systems that includes: (i) a ringfield camera; (ii) a source of radiation; (iii) a condenser for processing radiation from the source of radiation to produce a ringfield illumination field for illuminating a mask; (iv) a reticle that is positioned at the ringfield camera's object plane and from which a reticle image in the form of an intensity profile is reflected into the entrance pupil of the ringfield camera, wherein the reticle moves in a direction that is transverse to the length of the ringfield illumination field that illuminates the reticle; (v) detector for measuring the entire intensity along the length of the ringfield illumination field that is projected onto the reticle; and (vi) a wafer onto which the reticle imaged is projected from the ringfield camera.
Reticle stage based linear dosimeter
Berger, Kurt W.
2005-06-14
A detector to measure EUV intensity employs a linear array of photodiodes. The detector is particularly suited for photolithography systems that includes: (i) a ringfield camera; (ii) a source of radiation; (iii) a condenser for processing radiation from the source of radiation to produce a ringfield illumination field for illuminating a mask; (iv) a reticle that is positioned at the ringfield camera's object plane and from which a reticle image in the form of an intensity profile is reflected into the entrance pupil of the ringfield camera, wherein the reticle moves in a direction that is transverse to the length of the ringfield illumination field that illuminates the reticle; (v) detector for measuring the entire intensity along the length of the ringfield illumination field that is projected onto the reticle; and (vi) a wafer onto which the reticle imaged is projected from the ringfield camera.
PC Basic Linear Algebra Subroutines
Energy Science and Technology Software Center (OSTI)
1992-03-09
PC-BLAS is a highly optimized version of the Basic Linear Algebra Subprograms (BLAS), a standardized set of thirty-eight routines that perform low-level operations on vectors of numbers in single and double-precision real and complex arithmetic. Routines are included to find the index of the largest component of a vector, apply a Givens or modified Givens rotation, multiply a vector by a constant, determine the Euclidean length, perform a dot product, swap and copy vectors, andmore » find the norm of a vector. The BLAS have been carefully written to minimize numerical problems such as loss of precision and underflow and are designed so that the computation is independent of the interface with the calling program. This independence is achieved through judicious use of Assembly language macros. Interfaces are provided for Lahey Fortran 77, Microsoft Fortran 77, and Ryan-McFarland IBM Professional Fortran.« less
Linear induction accelerator parameter options
Birx, D.L.; Caporaso, G.J.; Reginato, L.L.
1986-04-21
The principal undertaking of the Beam Research Program over the past decade has been the investigation of propagating intense self-focused beams. Recently, the major activity of the program has shifted toward the investigation of converting high quality electron beams directly to laser radiation. During the early years of the program, accelerator development was directed toward the generation of very high current (>10 kA), high energy beams (>50 MeV). In its new mission, the program has shifted the emphasis toward the production of lower current beams (>3 kA) with high brightness (>10/sup 6/ A/(rad-cm)/sup 2/) at very high average power levels. In efforts to produce these intense beams, the state of the art of linear induction accelerators (LIA) has been advanced to the point of satisfying not only the current requirements but also future national needs.
Goswami, Srubabati [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India); Physik-Department, Technische Universitaet Muenchen, James-Franck-Strasse, D-85748 Garching (Germany); Rodejohann, Werner [Physik-Department, Technische Universitaet Muenchen, James-Franck-Strasse, D-85748 Garching (Germany)
2006-06-01
We analyze the constraints on neutrino mass spectra with extra sterile neutrinos as implied by the LSND experiment. The various mass related observables in neutrinoless double beta decay, tritium beta decay and cosmology are discussed. Both neutrino oscillation results as well as recent cosmological neutrino mass bounds are taken into account. We find that some of the allowed mass patterns are severely restricted by the current constraints, in particular, by the cosmological constraints on the total sum of neutrino masses and by the nonmaximality of the solar neutrino mixing angle. Furthermore, we estimate the form of the four neutrino mass matrices and also comment on the situation in scenarios with two additional sterile neutrinos.
Independent Oversight Inspection, Stanford Linear Accelerator Center -
Office of Environmental Management (EM)
January 2007 | Department of Energy Stanford Linear Accelerator Center - January 2007 Independent Oversight Inspection, Stanford Linear Accelerator Center - January 2007 January 2007 Inspection of Environment, Safety, and Health Programs at the Stanford Linear Accelerator Center This report provides the results of an inspection of the environment, safety, and health programs at the Department of Energy's (DOE) Stanford Linear Accelerator Center. The inspection was conducted during October
High Performance Preconditioners and Linear Solvers
Energy Science and Technology Software Center (OSTI)
2006-07-27
Hypre is a software library focused on the solution of large, sparse linear systems of equations on massively parallel computers.
Scaling factor inconsistencies in neutrinoless double beta decay
Cowell, S. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
2006-02-15
The modern theory of neutrinoless double beta decay includes a scaling factor that has often been treated inconsistently in the literature. The nuclear contribution to the decay half-life can be suppressed by 15%-20% when scaling factors are mismatched. Correspondingly,
Neutrinoless double-{beta} decay: Status and future
Bilenky, S. M. [Joint Institute for Nuclear Research (Russian Federation)], E-mail: bilenky@he.sissa.it
2006-12-15
A brief summary of the status of neutrino masses, mixing, and oscillations is presented. Neutrinoless double {beta} decay is considered. Predictions for the effective Majorana mass are reviewed. A possible test of the calculations of nuclear matrix elements of the 0{nu}{beta}{beta} decay is proposed.
Prompt proton decay in the vicinity of {sup 56}Ni
Johansson, E. K.; Rudolph, D.; Andersson, L-L.; Fahlander, C.; Rietz, R. du; Torres, D. A.; Carpenter, M. P.; Seweryniak, D.; Zhu, S.; Charity, R. J.; Chiara, C. J.; Hoel, C.; Pechenaya, O. L.; Reviol, W.; Sarantites, D. G.; Sobotka, L. G.; Ekman, J.
2007-11-30
A new decay mode, the so called prompt proton decay, was discovered in 1998. It has since proven to be an important decay mechanism for several neutron deficient nuclei in the A{approx}60 region. To measure with high accuracy the energies and angular distributions of these protons, a state-of-the-art charged particle detector--LuWuSiA--was developed. It was first utilized during a fusion-evaporation reaction experiment performed at Argonne National Laboratory, U.S.A. In this contribution, the characteristics of the prompt proton decay are discussed along with the special features of LuWuSiA as well as a revisit to the prompt proton decay in {sup 58}Cu.
Complex-Energy Shell-Model Description of Alpha Decay
Id Betan, R.; Nazarewicz, Witold
2011-01-01
In his pioneering work of alpha decay, Gamow assumed that the alpha particle formed inside the nucleus tunnels through the barrier of the alpha-daughter potential. The corresponding metastable state can be viewed as a complex-energy solution of the time-independent Schroedinger equation with the outgoing boundary condition. The formation of the alpha cluster, missing in the original Gamow formulation, can be described within the R-matrix theory in terms of the formation amplitude. In this work, the alpha decay process is described by computing the formation amplitude and barrier penetrability in a large complex-energy configuration space spanned by the complex-energy eigenstates of the finite Woods-Saxon (WS) potential. The proper normalization of the decay channel is essential as it strongly modifies the alpha-decay spectroscopic factor. The test calculations are carried out for the ^{212}Po alpha decay.
Imperfect World of beta beta-decay Nuclear Data Sets
Pritychenko, B.
2015-01-03
The precision of double-beta ββ-decay experimental half lives and their uncertainties is reanalyzed. The method of Benford's distributions has been applied to nuclear reaction, structure and decay data sets. First-digit distribution trend for ββ-decay T^{2v}_{1/2} is consistent with large nuclear reaction and structure data sets and provides validation of experimental half-lives. A complementary analysis of the decay uncertainties indicates deficiencies due to small size of statistical samples, and incomplete collection of experimental information. Further experimental and theoretical efforts would lead toward more precise values of-decay half-lives and nuclear matrix elements.
Decay of multispin multiquantum coherent states in the NMR of a solid
Zobov, V. E.; Lundin, A. A.
2011-03-15
A model based on the Anderson adiabatic approximation, which is widely used for describing various aspects of dynamic phenomena in conventional radiospectroscopy, is proposed for describing the decay of multispin multiquantum coherent states in a solid. The coherent state relaxation function is represented by the product of two functions corresponding to spin precession in a two-component local field with a correlated and an uncorrelated component. Theoretical results of this study explain the experimental data reported in a number of publications and are in good agreement with these data.
New non-linear photovoltaic effect in uniform bipolar semiconductor
Volovichev, I.
2014-11-21
A linear theory of the new non-linear photovoltaic effect in the closed circuit consisting of a non-uniformly illuminated uniform bipolar semiconductor with neutral impurities is developed. The non-uniform photo-excitation of impurities results in the position-dependant current carrier mobility that breaks the semiconductor homogeneity and induces the photo-electromotive force (emf). As both the electron (or hole) mobility gradient and the current carrier generation rate depend on the light intensity, the photo-emf and the short-circuit current prove to be non-linear functions of the incident light intensity at an arbitrarily low illumination. The influence of the sample size on the photovoltaic effect magnitude is studied. Physical relations and distinctions between the considered effect and the Dember and bulk photovoltaic effects are also discussed.
Confirming the Lanchestrian linear-logarithmic model of attrition
Hartley, D.S. III.
1990-12-01
This paper is the fourth in a series of reports on the breakthrough research in historical validation of attrition in conflict. Significant defense policy decisions, including weapons acquisition and arms reduction, are based in part on models of conflict. Most of these models are driven by their attrition algorithms, usually forms of the Lanchester square and linear laws. None of these algorithms have been validated. The results of this paper confirm the results of earlier papers, using a large database of historical results. The homogeneous linear-logarithmic Lanchestrian attrition model is validated to the extent possible with current initial and final force size data and is consistent with the Iwo Jima data. A particular differential linear-logarithmic model is described that fits the data very well. A version of Helmbold's victory predicting parameter is also confirmed, with an associated probability function. 37 refs., 73 figs., 68 tabs.
APPLICATION OF NEURAL NETWORK ALGORITHMS FOR BPM LINEARIZATION
Musson, John C.; Seaton, Chad; Spata, Mike F.; Yan, Jianxun
2012-11-01
Stripline BPM sensors contain inherent non-linearities, as a result of field distortions from the pickup elements. Many methods have been devised to facilitate corrections, often employing polynomial fitting. The cost of computation makes real-time correction difficult, particulalry when integer math is utilized. The application of neural-network technology, particularly the multi-layer perceptron algorithm, is proposed as an efficient alternative for electrode linearization. A process of supervised learning is initially used to determine the weighting coefficients, which are subsequently applied to the incoming electrode data. A non-linear layer, known as an ?activation layer,? is responsible for the removal of saturation effects. Implementation of a perceptron in an FPGA-based software-defined radio (SDR) is presented, along with performance comparisons. In addition, efficient calculation of the sigmoidal activation function via the CORDIC algorithm is presented.
Method and apparatus for reconstructing in-cylinder pressure and correcting for signal decay
Huang, Jian
2013-03-12
A method comprises steps for reconstructing in-cylinder pressure data from a vibration signal collected from a vibration sensor mounted on an engine component where it can generate a signal with a high signal-to-noise ratio, and correcting the vibration signal for errors introduced by vibration signal charge decay and sensor sensitivity. The correction factors are determined as a function of estimated motoring pressure and the measured vibration signal itself with each of these being associated with the same engine cycle. Accordingly, the method corrects for charge decay and changes in sensor sensitivity responsive to different engine conditions to allow greater accuracy in the reconstructed in-cylinder pressure data. An apparatus is also disclosed for practicing the disclosed method, comprising a vibration sensor, a data acquisition unit for receiving the vibration signal, a computer processing unit for processing the acquired signal and a controller for controlling the engine operation based on the reconstructed in-cylinder pressure.
Mixed symmetry states and {beta} decays of odd-A Xe to I isotopes
Al-Khudair, Falih H.
2009-07-15
The energy spectra of the parent and daughter nuclei in the {beta} decays ({sup 121-127}Xe,{beta}{sup +121-127}I) are considered in the interacting boson fermion model (IBFM-2) with the g{sub 7/2},d{sub 5/2},d{sub 3/2},s{sub 1/2}, and h{sub 11/2} single-particle orbitals. Electromagnetic transition probabilities and branching ratios in odd {sup 121-127}I isotopes are investigated. Special attention is given to the occurrence of mixed symmetry states, and the F-spin structures of the wave functions are analyzed. The log{sub 10}ft values of the allowed {beta} decay transitions are calculated. It is found that the IBFM-2 results agree with the experimental data quite well.
Search for the neutral MSSM Higgs bosons in the ditau decay channels at CDF Run II
Cuenca Almenar, Cristobal; /Valencia U., IFIC
2008-04-01
This thesis presents the results on a search for the neutral MSSM Higgs bosons decaying to tau pairs, with least one of these taus decays leptonically. The search was performed with a sample of 1.8 fb{sup -1} of proton-antiproton collisions at {radical}s = 1.96 TeV provided by the Tevatron and collected by CDF Run II. No significant excess over the Standard Model prediction was found and a 95% confidence level exclusion limit have been set on the cross section times branching ratio as a function of the Higgs boson mass. This limit has been translated into the MSSM Higgs sector parameter plane, tan{beta} vs. M{sub A}, for the four different benchmark scenarios.
Angular distribution of electrons in neutrinoless double-beta decay and new physics
Ali, A. [DESY (Germany); Borisov, A. V., E-mail: borisov@phys.msu.ru; Zhuridov, D. V. [Moscow State University (Russian Federation)
2007-07-15
For neutrinoless double-beta decay caused by the exchange of light Majorana neutrinos, an expression for the differential width with respect to the angle between the final-electron momenta is obtained on the basis of a Lorentz-invariant effective Lagrangian of the general form. The shape of this angular distribution is analyzed within various extensions of the Standard Model that allow this process-in particular, within theories that involve Majorana super partners and (or) right-handed currents. The angular correlation coefficient for electrons as a function of the mass of the right-handed W boson and the effective Majorana neutrino mass in the decay of the {sup 76}Ge nucleus is considered within the model involving left-right symmetry.
Theory of rare Kaon and Pion decays (Journal Article) | SciTech...
Office of Scientific and Technical Information (OSTI)
Theory of rare Kaon and Pion decays Citation Details In-Document Search Title: Theory of rare Kaon and Pion decays I discuss recent theoretical progress in rare (leptonic) decay...
Shock wave perturbation decay in granular materials
Vogler, Tracy J.
2015-11-05
A technique in which the evolution of a perturbation in a shock wave front is monitored as it travels through a sample is applied to granular materials. Although the approach was originally conceived as a way to measure the viscosity of the sample, here it is utilized as a means to probe the deviatoric strength of the material. Initial results for a tungsten carbide powder are presented that demonstrate the approach is viable. Simulations of the experiments using continuum and mesoscale modeling approaches are used to better understand the experiments. The best agreement with the limited experimental data is obtained for the mesoscale model, which has previously been shown to give good agreement with planar impact results. The continuum simulations indicate that the decay of the perturbation is controlled by material strength but is insensitive to the compaction response. Other sensitivities are assessed using the two modeling approaches. The simulations indicate that the configuration used in the preliminary experiments suffers from certain artifacts and should be modified to remove them. As a result, the limitations of the current instrumentation are discussed, and possible approaches to improve it are suggested.
Shock wave perturbation decay in granular materials
Vogler, Tracy J.
2015-11-05
A technique in which the evolution of a perturbation in a shock wave front is monitored as it travels through a sample is applied to granular materials. Although the approach was originally conceived as a way to measure the viscosity of the sample, here it is utilized as a means to probe the deviatoric strength of the material. Initial results for a tungsten carbide powder are presented that demonstrate the approach is viable. Simulations of the experiments using continuum and mesoscale modeling approaches are used to better understand the experiments. The best agreement with the limited experimental data is obtainedmore » for the mesoscale model, which has previously been shown to give good agreement with planar impact results. The continuum simulations indicate that the decay of the perturbation is controlled by material strength but is insensitive to the compaction response. Other sensitivities are assessed using the two modeling approaches. The simulations indicate that the configuration used in the preliminary experiments suffers from certain artifacts and should be modified to remove them. As a result, the limitations of the current instrumentation are discussed, and possible approaches to improve it are suggested.« less
Two-photon decay of pseudoscalar quarkonia
Lansberg, J. P.; Pham, T. N.
2008-08-29
We report on our recent evaluation of the two-photon width of the pseudoscalar quarkonia, {eta}{sub c}(nS) and {eta}{sub b}(nS) in an approach based on Heavy-Quark Spin Symmetry (HQSS). To what concerns the 1S state {eta}{sub c}, our parameter-free computation agrees with experiments, as well as most of other theoretical works. On the other hand, our computation for the 2S-state looks 2S like a confirmation that there may exist an anomaly related to the decay of {eta}{sub c}{sup '}, especially in the light of the new preliminary result of the Belle collaboration. We also point out that the essentially model-independent ratio of {eta}{sub b} two-photon width to the {upsilon} leptonic width and the {eta}{sub b} two-photon width could be used to extract the strong coupling constant {alpha}{sub s}.
Pionic contribution to neutrinoless double beta decay
Vergados, J. D. [Physics Department, University of Ioannina, Ioannina, GR 451 10 (Greece); Theory Division, CERN, Geneva (Switzerland); Faessler, Amand [Institute fuer Theoretische Physik, Universitaet Tuebingen (Germany); Toki, H. [RCNP, Osaka University, Osaka, 567-0047 (Japan)
2010-02-01
It is well known that neutrinoless double decay is going to play a crucial role in settling the neutrino properties, which cannot be extracted from the neutrino oscillation data. It is, in particular, expected to settle the absolute scale of neutrino mass and determine whether the neutrinos are Majorana particles, i.e. they coincide with their own antiparticles. In order to extract the average neutrino mass from the data, one must be able to estimate the contribution of all possible high mass intermediate particles. The latter, which occur in practically all extensions of the standard model, can, in principle, be differentiated from the usual mass term, if data from various targets are available. One, however, must first be able to reliably calculate the corresponding nuclear matrix elements. Such calculations are extremely difficult since the effective transition operators are very short ranged. For such operators processes like pionic contributions, which are usually negligible, turn out to be dominant. We study such an effect in a nonrelativistic quark model for the pion and the nucleon.
Tritium β decay in chiral effective field theory
Baroni, A.; Girlanda, L.; Kievsky, A.; Marcucci, L. E.; Schiavilla, R.; Viviani, M.
2016-08-18
We evaluate the Fermi and Gamow-Teller (GT) matrix elements in tritiummore » $$\\beta$$-decay by including in the charge-changing weak current the corrections up to one loop recently derived in nuclear chiral effective field theory ($$\\chi$$ EFT). The trinucleon wave functions are obtained from hyperspherical-harmonics solutions of the Schroedinger equation with two- and three-nucleon potentials corresponding to either $$\\chi$$ EFT (the N3LO/N2LO combination) or meson-exchange phenomenology (the AV18/UIX combination). We find that contributions due to loop corrections in the axial current are, in relative terms, as large as (and in some cases, dominate) those from one-pion exchange, which nominally occur at lower order in the power counting. Furthermore, we also provide values for the low-energy constants multiplying the contact axial current and three-nucleon potential, required to reproduce the experimental GT matrix element and trinucleon binding energies in the N3LO/N2LO and AV18/UIX calculations.« less
Dynamics of excimer formation and decay in supercritical krypton
Holroyd, Richard A.; Cook, Andrew R.; Preses, Jack M.
2009-12-14
New infrared absorbing species are identified in the pulse radiolysis of supercritical Kr at high pressures. The species are believed to be excimers. Their formation and decay rates have been time resolved using the Laser Electron Accelerator Facility. An initial species, formed in less than 1 ns, absorbs at several wavelengths between 790 and 1300 nm; The decay of this species is initially fast, followed by a slower component; the decay rate increases with pressure. As this initial species decays a second excimer is formed absorbing at 830, 890, and 990 nm. The growth and decay rates of this excimer are also pressure dependent. A third excimer, absorbing between 1000 and 1200 nm grows at a rate similar to that of the decay of the second species. The decay rate of the third species is also pressure dependent; the lifetime increases from 9.4 ns at 109 bar to 49 ns at 15 bar. A kinetic mechanism is proposed that satisfactorily reproduces the experimental results. The first species is identified as a higher energy gerade triplet state excimer and the second as the singlet gerade state.
Gamma-ray burst spectrum with decaying magnetic field
Zhao, Xiaohong; Bai, Jinming [Yunnan Observatory, Chinese Academy of Sciences, P.O. Box 110, 650011 Kunming (China); Li, Zhuo [Department of Astronomy and Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Liu, Xuewen; Zhang, Bin-bin; Mszros, Peter, E-mail: zhaoxh@ynao.ac.cn, E-mail: zhuo.li@pku.edu.cn [Department of Astronomy and Astrophysics and Department of Physics, The Pennsylvania State University, University Park, PA 16802 (United States)
2014-01-01
In the internal shock model for gamma-ray bursts (GRBs), the synchrotron spectrum from the fast cooling electrons in a homogeneous downstream magnetic field (MF) is too soft to produce the low-energy slope of GRB spectra. However, the MF may decay downstream with distance from the shock front. Here we show that the synchrotron spectrum becomes harder if electrons undergo synchrotron and inverse-Compton cooling in a decaying MF. To reconcile this with the typical GRB spectrum with low-energy slope ?F {sub ?}??, the postshock MF decay time must be comparable to the cooling time of the bulk electrons (corresponding to a MF decaying length typically of ?10{sup 5} skin depths); that the inverse-Compton cooling should dominate synchrotron cooling after the MF decay time; and/or that the MF decays with comoving time roughly as B?t {sup 1.5}. An internal shock synchrotron model with a decaying MF can account for the majority of GRBs with low-energy slopes not harder than ?{sup 4/3}.
Measurement of indirect CP-violating asymmetries in D0?K+K- and D0??+?- decays at CDF
Aaltonen, Timo Antero
2014-12-30
We report a measurement of the indirect CP-violating asymmetries (A?) between effective lifetimes of anticharm and charm mesons reconstructed in D0?K+K- and D0??+?- decays. We use the full data set of proton-antiproton collisions collected by the Collider Detector at Fermilab experiment and corresponding to 9.7 fb-1 of integrated luminosity. The strong-interaction decay D*+?D0?+ is used to identify the meson at production as D0 or D0. We statistically subtract D0 and D0 mesons originating from b-hadron decays and measure the yield asymmetry between anticharm and charm decays as a function of decay time. We measure A?(K+K-)=(-0.190.15(stat)0.04(syst))%and A?(?+?-)=(-0.010.18(stat)0.03(syst))%. The results are consistentmorewith the hypothesis of CP symmetry and their combination yields A?=(-0.120.12)%.less
Rare {Lambda}{sub b} decays in a quark model
Mott, L.; Roberts, W.
2010-08-05
Hadronic form factors for the rare weak transitions {Lambda}{sub b{yields}{Lambda}}{sup (*)} are calculated using a nonrelativistic quark model. The form factors obtained in this way are found to satisfy the relationships expecetd from the heavy quark effective theory. Differential decay rates and branching ratios are calculated for the dileptonic decays {Lambda}{sub b{yields}{Lambda}}{sup (*)}l{sup +}l{sup -}, for both ground state and excited daughter baryons. Inclusion of the long distance contributions from charmonium resonances significantly enhances the decay rates. Future work is outlined.
Study of Scalar Mesons and Related Radiative Decays
Deirdre Black; Masayasu Harada; Joseph Schechter
2002-06-01
After a brief review of the puzzling light scalar meson sector of QCD, a brief summary will be given of a paper concerning radiative decays involving the light scalars. There, a simple vector meson dominance model is constructed in an initial attempt to relate a large number of the radiative decays involving a putative scalar nonet to each other. As an application it is illustrated why a{sub 0}(980)-f{sub 0}(980) mixing is not expected to greatly alter the f{sub 0}/a{sub 0} production ratio for radiative {phi} decays.
Searches for New Physics in Top Decays at D0
Pleier, Marc-Andre; /Brookhaven
2011-08-01
The Tevatron proton-antiproton collider at Fermilab with its centre of mass energy of 1.96 TeV allows for pair production of top quarks and the study of top quark decay properties. This report reflects the current status of measurements of the W boson helicity in top quark decays and the ratio of top quark branching fractions as well as searches for neutral current top quark decays and pair production of fourth generation t' quarks, performed by the D0 Collaboration utilising datasets of up to 5.4 fb{sup -1}.
Recent BaBar Results on $B$ Decays
Clark, P.J.; /Edinburgh U.
2011-11-15
Several recent key results from the BABAR experiment are presented, most using 383.6 fb{sup -1} of data. In particular, the search for B{sup +} {yields} {tau}{sup +}{nu}, inclusive and exclusive measurements of |V{sub ub}|, measurements of b {yields} d{gamma} decays and new observations of rare charmless hadronic decays. The new results provide important experimental constraints on the Standard Model and new physics models. Keywords: B decays; flavor; leptonic; semi-leptonic, radiative, hadronic.
Cold fusion: externally induced beta decay of the deuteron?
Driscoll, R.B.
1995-04-01
Plasma frequencies {nu}{sub e} of interstitial electrons in palladium crystals charged with deuterium by electrolysis can reach resonance with the beats of de Broglie group frequencies of deuterons. This frequency can occur during acoustic compressions of lattices due to (1) bubble formation at the Pd cathode, (2) particles from cosmic ray showers, and (3) beta decays of deuterons. Resonance perturbs the orbits of deuterons nucleon constituents with a finite probability of causing dissociation and beta decay -- that is the basic conjecture. The exponential tendency resulting from cause (3) of lattice compression is limited by melting of the lattice, whose integrity is essential for {nu}{sub e}, which drives the decays.
Beta decay of 32Ar for fundamental tests
U.S. Department of Energy (DOE) all webpages (Extended Search)
Beta decay of 32 Ar for fundamental tests Chris Wrede University of Washington Argonne-ATLAS user meeting August 8 th , 2009 Outline * 1999 measurement of positron-neutrino correlation in 32 Ar(e + nu e ): ISOL facility (CERN-ISOLDE) * 2008 measurement the ft value for superallowed 32 Ar(e + nu e ) decay to test isospin symmetry breaking corrections: fragmentation facility (MSU-NSCL) * Where does ATLAS fit in to this? A bridge from stability to 32 Ar! Detecting scalar currents in weak decays n e
Multiple particle emission after {sup 11}Li beta-decay: exploring new decay channels
Madurga, M.; Borge, M. J. G.; Fynbo, H. O. U.; Prezado, Y.; Tengblad, O.; Jonson, B.; Nyman, G.; Riisager, K.
2007-11-30
We present here a study of the three-body, n{alpha}{sup 6}He particle break-up of {sup 11}Be(10.6) following {sup 11}Li {beta}-decay. The emitted charged particles were detected in coincidence using a cubic set-up of highly segmented silicon detectors, allowing us to measure simultaneously energy and trajectory. The three body break-up of {sup 11}Be(10.5) through the intermediate state {sup 10}Be(9.6) was modeled using the multiple-level single-channel R-Matrix formalism.
Decays Ξ b → Λ b π and diquark correlations in hyperons...
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Decays b b and diquark correlations in hyperons Prev Next Title: Decays b b and diquark correlations in hyperons Authors: Li, Xin ; Voloshin, M. B. ...
Decays Ξ b → Λ b π and diquark correlations in hyperons...
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Decays b b and diquark correlations in hyperons Citation Details In-Document Search Title: Decays b b and diquark correlations in hyperons Authors: Li, ...
International Workshop on Linear Colliders 2010
None
2011-10-06
IWLC2010 International Workshop on Linear Colliders 2010ECFA-CLIC-ILC joint meeting: Monday 18 October - Friday 22 October 2010Venue: CERN and CICG (International Conference Centre Geneva, Switzerland) This year, the International Workshop on Linear Colliders organized by the European Committee for Future Accelerators (ECFA) will study the physics, detectors and accelerator complex of a linear collider covering both CLIC and ILC options.Contact Workshop Secretariat IWLC2010 is hosted by CERN
Ultra-high vacuum photoelectron linear accelerator
Yu, David U.L.; Luo, Yan
2013-07-16
An rf linear accelerator for producing an electron beam. The outer wall of the rf cavity of said linear accelerator being perforated to allow gas inside said rf cavity to flow to a pressure chamber surrounding said rf cavity and having means of ultra high vacuum pumping of the cathode of said rf linear accelerator. Said rf linear accelerator is used to accelerate polarized or unpolarized electrons produced by a photocathode, or to accelerate thermally heated electrons produced by a thermionic cathode, or to accelerate rf heated field emission electrons produced by a field emission cathode.
International Linear Collider Technical Design Report - Volume...
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Design Report - Volume 2: Physics Citation Details In-Document Search Title: International Linear Collider Technical Design Report - Volume 2: Physics You are accessing a ...
International Linear Collider Technical Design Report - Volume...
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Linear Collider Technical Design Report - Volume 2: Physics Baer, Howard; Barklow, Tim; Fujii, Keisuke; Gao, Yuanning; Hoang, Andre; Kanemura, Shinya; List, Jenny; Logan, Heather...
Independent Oversight Inspection, Stanford Linear Accelerator...
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Safety, and Health Programs at the Stanford Linear Accelerator Center This report provides the results of an inspection of the environment, safety, and health programs at the ...
The Linear Engine Pathway of Transformation
This poster highlights the major milestones in the history of the linear engine in terms of technological advances, novel designs, and economic/social impact.
LED Replacements for Linear Fluorescent Lamps Webcast
In this June 20, 2011 webcast on LED products marketed as replacements for linear fluorescent lamps, Jason Tuenge of the Pacific Northwest National Laboratory (PNNL) discussed current Lighting...
Nuclear Decay Data Evaluations at IFIN-HH, Romania
Luca, A.
2014-06-15
An IAEA Coordinated Research Project (CRP) on Updated Decay Data Library for Actinides was implemented during the period 2005-2012. The author participated in the CRP, as a representative of the Horia Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH), the Radionuclide Metrology Laboratory. Decay data for five actinide nuclides were evaluated by the author, according to the procedures and rules of the international cooperation Decay Data Evaluation Project (DDEP): {sup 236}U, {sup 234}Th, {sup 228}Ra, {sup 211}Bi and {sup 211}Po. The most important results, conclusions and some recommendations of the evaluator are presented. The IFIN-HH involvement in several new international and national research projects in the field is briefly mentioned; new evaluations and experimental determination of some nuclear decay data (photon absolute emission probability, half-life) for nuclear medicine applications are foreseen.
Observation of the Decay B??Ds(*)+K?l????l
del Amo Sanchez, P.; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; et al
2011-07-22
We report the observation of the decay B??Ds(*)+K?l??l based on 342fb? of data collected at the ?(4S) resonance with the BABAR detector at the PEP-II e?e? storage rings at SLAC. A simultaneous fit to three D+s decay chains is performed to extract the signal yield from measurements of the squared missing mass in the B meson decay. We observe the decay B??Ds(*)+K?l??l with a significance greater than 5 standard deviations (including systematic uncertainties) and measure its branching fraction to be B(B??Ds(*)+K?l??l)=[6.13+1.04-1.03(stat)0.43(syst)0.51(B(Ds))]10??, where the last error reflects the limited knowledge of the Ds branching fractions.
Hierarchy of scales in B{yields}PS decays
Delepine, D.; Lucio M, J. L.; Mendoza S, J. A.; Ramirez, Carlos A.
2008-08-31
We show that the naive factorization approach can accommodate the existence of the observed hierarchy of branching ratios for the B{yields}PS decays (P stands for pseudoscalar and S for scalar mesons respectively.
OSTIblog Articles in the neutrinos Neutrinoless Double Beta Decay...
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Neutrinoless Double Beta Decay Topic Mining for Gold, Neutrinos and the Neutrinoless ... The site of the former Homestake Mine was once one of the largest and deepest gold mines ...
A Direct Measurement of the $W$ Decay Width
Vine, Troy
2008-08-01
A direct measurement of the W boson total decay width is presented in proton-antiproton collisions at √s = 1.96 TeV using data collected by the CDF II detector. The measurement is made by fitting a simulated signal to the tail of the transverse mass distribution in the electron and muon decay channels. An integrated luminosity of 350 pb^{-1} is used, collected between February 2002 and August 2004. Combining the results from the separate decay channels gives the decay width as 2.038 ± 0.072 GeV in agreement with the theoretical prediction of 2.093 ± 0.002 GeV. A system is presented for the management of detector calibrations using a relational database schema. A description of the implementation and monitoring of a procedure to provide general users with a simple interface to the complete set of calibrations is also given.
DOE Science Showcase - Neutrinoless Double Beta Decay | OSTI...
Office of Scientific and Technical Information (OSTI)
Neutrinos are created as a result of certain types of radioactive decay, or nuclear reactions such as those that take place in the Sun, in nuclear reactors, or when cosmic rays hit ...
Material degradation detection by ultrasonic decay constant measurement
Maeda, Noriyoshi; Yamaguchi, Atsunori; Sugibayashi, Takuya
1995-12-01
Structural materials used in a nuclear power plant may be degraded mainly by fatigue, neutron irradiation embrittlement or thermal embrittlement. in order to improve the availability and reliability of a nuclear power plant, it is especially advantageous to detect nondestructively the degradation as early as possible and to prevent possible failures. Measurement of change of ultrasonic decay constant has been proposed as promising degradation detection method. In this study, measurement of frequency dependence of decay constant of ultrasonic wave during propagation in materials is introduced. By exciting an EMAT (electromagnetic ultrasonic transducer) with sine burst wave and processing the ringing signals with a superheterodyne phase sensitive detector, decay constant is measured at the resonance frequency for platetype test specimen. Based on these results, it was confirmed that the relation between frequency and decay constant varied with the degree of material degradation and also with the amplitude of residual stress.
Complementarity of Neutrinoless Double Beta Decay and Cosmology
Dodelson, Scott; Lykken, Joseph
2014-03-20
Neutrinoless double beta decay experiments constrain one combination of neutrino parameters, while cosmic surveys constrain another. This complementarity opens up an exciting range of possibilities. If neutrinos are Majorana particles, and the neutrino masses follow an inverted hierarchy, then the upcoming sets of both experiments will detect signals. The combined constraints will pin down not only the neutrino masses but also constrain one of the Majorana phases. If the hierarchy is normal, then a beta decay detection with the upcoming generation of experiments is unlikely, but cosmic surveys could constrain the sum of the masses to be relatively heavy, thereby producing a lower bound for the neutrinoless double beta decay rate, and therefore an argument for a next generation beta decay experiment. In this case as well, a combination of the phases will be constrained.
Phenomenology of semileptonic B -meson decays with form factors...
Office of Scientific and Technical Information (OSTI)
of semileptonic B -meson decays with form factors from lattice QCD Authors: Du, Daping ; El-Khadra, A. X. ; Gottlieb, Steven ; Kronfeld, A. S. ; Laiho, J. ; Lunghi, E. ; Van de...
Decay of helical Kelvin waves on a quantum vortex filament
Van Gorder, Robert A.
2014-07-15
We study the dynamics of helical Kelvin waves moving along a quantum vortex filament driven by a normal fluid flow. We employ the vector form of the quantum local induction approximation (LIA) due to Schwarz. For an isolated filament, this is an adequate approximation to the full Hall-Vinen-Bekarevich-Khalatnikov dynamics. The motion of such Kelvin waves is both translational (along the quantum vortex filament) and rotational (in the plane orthogonal to the reference axis). We first present an exact closed form solution for the motion of these Kelvin waves in the case of a constant amplitude helix. Such solutions exist for a critical wave number and correspond exactly to the Donnelly-Glaberson instability, so perturbations of such solutions either decay to line filaments or blow-up. This leads us to consider helical Kelvin waves which decay to line filaments. Unlike in the case of constant amplitude helical solutions, the dynamics are much more complicated for the decaying helical waves, owing to the fact that the rate of decay of the helical perturbations along the vortex filament is not constant in time. We give an analytical and numerical description of the motion of decaying helical Kelvin waves, from which we are able to ascertain the influence of the physical parameters on the decay, translational motion along the filament, and rotational motion, of these waves (all of which depend nonlinearly on time). One interesting finding is that the helical Kelvin waves do not decay uniformly. Rather, such waves decay slowly for small time scales, and more rapidly for large time scales. The rotational and translational velocity of the Kelvin waves depend strongly on this rate of decay, and we find that the speed of propagation of a helical Kelvin wave along a quantum filament is large for small time while the wave asymptotically slows as it decays. The rotational velocity of such Kelvin waves along the filament will increase over time, asymptotically reaching a finite
Automating linear accelerator quality assurance
Eckhause, Tobias; Thorwarth, Ryan; Moran, Jean M.; Al-Hallaq, Hania; Farrey, Karl; Ritter, Timothy; DeMarco, John; Pawlicki, Todd; Kim, Gwe-Ya; Popple, Richard; Sharma, Vijeshwar; Park, SungYong; Perez, Mario; Booth, Jeremy T.
2015-10-15
Purpose: The purpose of this study was 2-fold. One purpose was to develop an automated, streamlined quality assurance (QA) program for use by multiple centers. The second purpose was to evaluate machine performance over time for multiple centers using linear accelerator (Linac) log files and electronic portal images. The authors sought to evaluate variations in Linac performance to establish as a reference for other centers. Methods: The authors developed analytical software tools for a QA program using both log files and electronic portal imaging device (EPID) measurements. The first tool is a general analysis tool which can read and visually represent data in the log file. This tool, which can be used to automatically analyze patient treatment or QA log files, examines the files for Linac deviations which exceed thresholds. The second set of tools consists of a test suite of QA fields, a standard phantom, and software to collect information from the log files on deviations from the expected values. The test suite was designed to focus on the mechanical tests of the Linac to include jaw, MLC, and collimator positions during static, IMRT, and volumetric modulated arc therapy delivery. A consortium of eight institutions delivered the test suite at monthly or weekly intervals on each Linac using a standard phantom. The behavior of various components was analyzed for eight TrueBeam Linacs. Results: For the EPID and trajectory log file analysis, all observed deviations which exceeded established thresholds for Linac behavior resulted in a beam hold off. In the absence of an interlock-triggering event, the maximum observed log file deviations between the expected and actual component positions (such as MLC leaves) varied from less than 1% to 26% of published tolerance thresholds. The maximum and standard deviations of the variations due to gantry sag, collimator angle, jaw position, and MLC positions are presented. Gantry sag among Linacs was 0.336 ± 0.072 mm. The
New timing system for the Stanford Linear Collider
Paffrath, L.; Bernstein, D.; Kang, H.; Koontz, R.; Leger, G.; Ross, M.; Pierce, W.; Wilmunder, A.
1984-11-01
In order to be able to meet the goals of the Stanford Linear Collider, a much more precise timing system had to be implemented. This paper describes the specification and design of this system, and the results obtained from its use on 1/3 of the SLAC linac. The functions of various elements are described, and a programmable delay unit (PDU) is described in detail.
Higgs boson decays in the littlest Higgs model
Gonzalez-Sprinberg, G.A.; Martinez, R.; Rodriguez, J.-Alexis
2005-02-01
We calculate the two body Higgs boson decays in the framework of the littlest Higgs model. The decay H{yields}{gamma}Z is computed at one-loop-level and, using previous results, we evaluate the branching fractions in the framework of the littlest Higgs model. A wide range of the space parameter of the model is considered and possible deviations from the standard model are explored.
Decay instability of a whistler in a plasma
Tewari, D.P.; Sharma, R.R.
1981-08-01
The parametric instabilities of a high power whistler in a high-density plasma possess large growth rates when the scattered sideband is an electrostatic lower hybrid mode. The efficient channels of decay include oscillating two stream instability, nonlinear Landau damping, and resonant decay involving ion acoustic and ion cyclotron modes. The processes of nonlinear scattering i.e., the ones possessing whistler sidebands are relatively less significant.
Effect of nuclear deformation on double beta decay
Rodin, Vadim [Institute fuer Theoretische Physik der Universitaet Tuebingen, D-72076 Tuebingen (Germany)
2009-11-09
The existing ways of accounting for deformation in recent calculations of neutrinoless double beta decay matrix elements are discussed. From an analysis of relevant experimental data it is argued that only {sup 150}Nd reveals convincing evidences of strong static deformation, which should eventually be taken into account in QRPA calculations. A proposal which allows in principle to measure the neutrino less double beta decay Fermi matrix element is briefly described.
Pond, R.B.; Matos, J.E.
1996-12-31
This document has been prepared to assist research reactor operators possessing spent fuel containing enriched uranium of United States origin to prepare part of the documentation necessary to ship this fuel to the United States. Data are included on the nuclear mass inventory, photon dose rate, and thermal decay heat of spent research reactor fuel assemblies. Isotopic masses of U, Np, Pu and Am that are present in spent research reactor fuel are estimated for MTR, TRIGA and DIDO-type fuel assembly types. The isotopic masses of each fuel assembly type are given as functions of U-235 burnup in the spent fuel, and of initial U-235 enrichment and U-235 mass in the fuel assembly. Photon dose rates of spent MTR, TRIGA and DIDO-type fuel assemblies are estimated for fuel assemblies with up to 80% U-235 burnup and specific power densities between 0.089 and 2.857 MW/kg[sup 235]U, and for fission product decay times of up to 20 years. Thermal decay heat loads are estimated for spent fuel based upon the fuel assembly irradiation history (average assembly power vs. elapsed time) and the spent fuel cooling time.
Higgs production and decay in models of a warped extra dimension with a bulk Higgs
Archer, Paul R.; Carena, Marcela; Carmona, Adrian; Neubert, Matthias
2015-01-13
Warped extra-dimension models in which the Higgs boson is allowed to propagate in the bulk of a compact AdS? space are conjectured to be dual to models featuring a partially composite Higgs boson. They offer a framework with which to investigate the implications of changing the scaling dimension of the Higgs operator, which can be used to reduce the constraints from electroweak precision data. In the context of such models, we calculate the cross section for Higgs production in gluon fusion and the H ? ?? decay rate and show that they are finite (at one-loop order) as a consequencemoreof gauge invariance. The extended scalar sector comprising the Kaluza-Klein excitations of the Standard Model scalars is constructed in detail. The largest effects are due to virtual KK fermions, whose contributions to the cross section and decay rate introduce a quadratic sensitivity to the maximum allowed value y* of the random complex entries of the 5D anarchic Yukawa matrices. We find an enhancement of the gluon-fusion cross section and a reduction of the H ? ?? rate as well as of the tree-level Higgs couplings to fermions and electroweak gauge bosons. We perform a detailed study of the correlated signal strengths for different production mechanisms and decay channels as functions of y*, the mass scale of Kaluza-Klein resonances and the scaling dimension of the composite Higgs operator.less
Higgs production and decay in models of a warped extra dimension with a bulk Higgs
Archer, Paul R.; Carena, Marcela; Carmona, Adrian; Neubert, Matthias
2015-01-13
Warped extra-dimension models in which the Higgs boson is allowed to propagate in the bulk of a compact AdS? space are conjectured to be dual to models featuring a partially composite Higgs boson. They offer a framework with which to investigate the implications of changing the scaling dimension of the Higgs operator, which can be used to reduce the constraints from electroweak precision data. In the context of such models, we calculate the cross section for Higgs production in gluon fusion and the H ? ?? decay rate and show that they are finite (at one-loop order) as a consequence of gauge invariance. The extended scalar sector comprising the Kaluza-Klein excitations of the Standard Model scalars is constructed in detail. The largest effects are due to virtual KK fermions, whose contributions to the cross section and decay rate introduce a quadratic sensitivity to the maximum allowed value y_{*} of the random complex entries of the 5D anarchic Yukawa matrices. We find an enhancement of the gluon-fusion cross section and a reduction of the H ? ?? rate as well as of the tree-level Higgs couplings to fermions and electroweak gauge bosons. We perform a detailed study of the correlated signal strengths for different production mechanisms and decay channels as functions of y_{*}, the mass scale of Kaluza-Klein resonances and the scaling dimension of the composite Higgs operator.
Reheating dynamics affects non-perturbative decay of spectator fields
Enqvist, Kari; Lerner, Rose N.; Rusak, Stanislav E-mail: rose.lerner@helsinki.fi
2013-11-01
The behaviour of oscillating scalar spectator fields after inflation depends on the thermal background produced by inflaton decay. Resonant decay of the spectator is often blocked by large induced thermal masses. We account for the finite decay width of the inflaton and the protracted build-up of the thermal bath to determine the early evolution of a homogeneous spectator field ? coupled to the Higgs Boson ? through the term g{sup 2}?{sup 2}?{sup 2}, the only renormalisable coupling of a new scalar to the Standard Model. We find that for very large higgs-spectator coupling g?>10{sup ?3}, the resonance is not always blocked as was previously suggested. As a consequence, the oscillating spectator can decay quickly. For other parameter values, we find that although qualitative features of the thermal blocking still hold, the dynamics are altered compared to the instant decay case. These findings are important for curvaton models, where the oscillating field must be relatively long lived in order to produce the curvature perturbation. They are also relevant for other spectator fields, which must decay sufficiently early to avoid spoiling the predictions of baryogenesis and nucleosynthesis.
Physics and Outlook for Rare, All-neutral Eta Decays
Mack, David J.
2014-06-01
The $\\eta$ meson provides a laboratory to study isospin violation and search for new flavor-conserving sources of C and CP violation with a sensitivity approaching $10^{-6}$ of the isospin-conserving strong amplitude. Some of the most interesting rare $\\eta$ decays are the neutral modes, yet the effective loss of photons from the relatively common decay $\\eta \\rightarrow 3\\pi^0 \\rightarrow 6\\gamma$ (33$\\%$) has largely limited the sensitivity for decays producing 3-5$\\gamma$'s. Particularly important relevant branches include the highly suppressed $\\eta \\rightarrow \\pi^0 2\\gamma \\rightarrow 4\\gamma$, which provides a rare window on testing models of $O(p^6)$ contributions in ChPTh, and $\\eta \\rightarrow 3\\gamma$ and $\\eta \\rightarrow 2\\pi^0 \\gamma \\rightarrow 5\\gamma$ which provide direct constraints on C violation in flavor-conserving processes. The substitution of lead tungstate in the forward calorimeter of the GluEx setup in Jefferson Lab's new Hall D would allow dramatically improved measurements. The main niche of this facility, which we call the JLab Eta Factory (JEF), would be $\\eta$ decay neutral modes. However, this could likely be expanded to rare $\\eta'(958)$ decays for low energy QCD studies as well as $\\eta$ decays involving muons for new physics searches.
Study of the D0 ---> pi- pi+ pi- pi+ decay
Link, J.M.; Yager, P.M.; Anjos, J.C.; Bediaga, I.; Castromonte, C.; Machado, A.A.; Magnin, J.; Massafferri, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; /Rio de Janeiro, CBPF /CINVESTAV, IPN /Colorado U. /Fermilab /Frascati /Guanajuato U. /Illinois U., Urbana /Indiana U. /Korea U. /Kyungpook Natl. U. /INFN, Milan /Milan U.
2007-01-01
Using data from the FOCUS (E831) experiment at Fermilab, they present new measurements for the Cabbibo-suppressed decay mode D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +}. They measure the branching ratio {Lambda}(D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{sup -} {pi}{sup +}{pi}{sup -}{pi}{sup +}) = 0.0914 {+-} 0.0018 {+-} 0.0022. An amplitude analysis has been performed, a first for this channel, in order to determine the resonant substructure of this decay mode. The dominant component is the decay D{sup 0} {yields} a{sub 1}(1260){sup +}{pi}{sup -}, accounting for 60% of the decay rate. The second most dominant contribution comes from the decay D{sup 0} {yields} {rho}(770){sup 0}{rho}(770){sup 0}, with a fraction of 25%. They also study the a{sub 1}(1260) line shape and resonant substructure. Using the helicity formalism for the angular distribution of the decay D{sup 0} {yields} {rho}(770){sup 0}{rho}(770){sup 0}, they measure a longitudinal polarization of P{sub L} = (71 {+-} 4 {+-} 2)%.
Hadronic decays of the D/sub s/ meson
Wasserbaech, S.R.
1989-06-01
The D/sub s//sup +/ is the lowest-lying pseudoscalar meson containing charm and anti-strange quarks. Evidence for this state was first reported in 1977, although more recent observations disagree with some of the early results. Since 1983 the weakly decaying D/sub s//sup +/ has been observed in many experiments. Relative branching fractions have been measured for many non-leptonic decay modes, including D/sub s//sup +/ /yields/ /phi//pi//sup +/, /phi//pi//sup +//pi//sup +//pi//sup /minus//, /bar K/*/sup 0/K/sup +/, and f/sub 0/(975)/pi//sup +/. The absolute branching fractions are estimated in high energy e/sup +/e/sup /minus// annihilation from the observed numbers of reconstructed D/sub s//sup +/ decays and the expected D/sub s//sup +/ production cross section. The lowest-lying vector c/bar s/ meson, the D/sub s/*/sup +/, has also been seen in its decay to /gamma/D/sub s//sup +/. Weak decays of the heavy quark and lepton flavors are relevant to the development of the Standard Model of both the electroweak and the strong interactions. Measurements of charmed particle weak decay are useful for determining the parameter of the Standard Model and for testing phenomenological models which include strong effects. 83 refs., 56 figs., 12 tabs.
Makwana, K. D. Cattaneo, F.; Zhdankin, V.; Li, H.; Daughton, W.
2015-04-15
Simulations of decaying magnetohydrodynamic (MHD) turbulence are performed with a fluid and a kinetic code. The initial condition is an ensemble of long-wavelength, counter-propagating, shear-Alfvén waves, which interact and rapidly generate strong MHD turbulence. The total energy is conserved and the rate of turbulent energy decay is very similar in both codes, although the fluid code has numerical dissipation, whereas the kinetic code has kinetic dissipation. The inertial range power spectrum index is similar in both the codes. The fluid code shows a perpendicular wavenumber spectral slope of k{sub ⊥}{sup −1.3}. The kinetic code shows a spectral slope of k{sub ⊥}{sup −1.5} for smaller simulation domain, and k{sub ⊥}{sup −1.3} for larger domain. We estimate that collisionless damping mechanisms in the kinetic code can account for the dissipation of the observed nonlinear energy cascade. Current sheets are geometrically characterized. Their lengths and widths are in good agreement between the two codes. The length scales linearly with the driving scale of the turbulence. In the fluid code, their thickness is determined by the grid resolution as there is no explicit diffusivity. In the kinetic code, their thickness is very close to the skin-depth, irrespective of the grid resolution. This work shows that kinetic codes can reproduce the MHD inertial range dynamics at large scales, while at the same time capturing important kinetic physics at small scales.
Non-Linear Seismic Soil Structure Interaction (SSI) Method for...
Office of Environmental Management (EM)
Non-Linear Seismic Soil Structure Interaction (SSI) Method for Developing Non-Linear Seismic SSI Analysis Techniques Non-Linear Seismic Soil Structure Interaction (SSI) Method for ...
Top-pair production and decay at NLO matched with parton showers
Campbell, John M.; Ellis, R. Keith; Nason, Paolo; Re, Emanuele
2015-04-21
We present a next-to-leading order (NLO) calculation of tt¯ production in hadronic collisions interfaced to shower generators according to the POWHEG method. We start from an NLO result from previous work, obtained in the zero width limit, where radiative corrections to both production and decays are included. The POWHEG interface required an extension of the POWHEG BOX framework, in order to deal with radiation from the decay of resonances. This extension is fully general (i.e. it can be applied in principle to any process considered in the zero width limit), and is here applied for the first time. In ordermore » to perform a realistic simulation, we introduce finite width effects using different approximations, that we validated by comparing with published exact NLO results. We have interfaced our POWHEG code to the PYTHIA8 shower Monte Carlo generator. At this stage, we dealt with novel issues related to the treatment of resonances, especially with regard to the initial scale for the shower that needs to be set appropriately. This procedure affects, for example, the fragmentation function of the b quark, that we have studied with particular attention. We believe that the tool presented here improves over previous generators for all aspects that have to do with top decays, and especially for the study of issues related to top mass measurements that involve B hadrons or b jets. As a result, the work presented here also constitutes a first step towards a fully consistent matching of NLO calculations involving intermediate resonances decaying into coloured particles, with parton showers.« less
Top-pair production and decay at NLO matched with parton showers
Campbell, John M.; Ellis, R. Keith; Nason, Paolo; Re, Emanuele
2015-04-21
We present a next-to-leading order (NLO) calculation of tt production in hadronic collisions interfaced to shower generators according to the POWHEG method. We start from an NLO result from previous work, obtained in the zero width limit, where radiative corrections to both production and decays are included. The POWHEG interface required an extension of the POWHEG BOX framework, in order to deal with radiation from the decay of resonances. This extension is fully general (i.e. it can be applied in principle to any process considered in the zero width limit), and is here applied for the first time. In order to perform a realistic simulation, we introduce finite width effects using different approximations, that we validated by comparing with published exact NLO results. We have interfaced our POWHEG code to the PYTHIA8 shower Monte Carlo generator. At this stage, we dealt with novel issues related to the treatment of resonances, especially with regard to the initial scale for the shower that needs to be set appropriately. This procedure affects, for example, the fragmentation function of the b quark, that we have studied with particular attention. We believe that the tool presented here improves over previous generators for all aspects that have to do with top decays, and especially for the study of issues related to top mass measurements that involve B hadrons or b jets. The work presented here also constitutes a first step towards a fully consistent matching of NLO calculations involving intermediate resonances decaying into coloured particles, with parton showers.
Top-pair production and decay at NLO matched with parton showers
Campbell, John M.; Ellis, R. Keith; Nason, Paolo; Re, Emanuele
2015-04-21
We present a next-to-leading order (NLO) calculation of tt production in hadronic collisions interfaced to shower generators according to the POWHEG method. We start from an NLO result from previous work, obtained in the zero width limit, where radiative corrections to both production and decays are included. The POWHEG interface required an extension of the POWHEG BOX framework, in order to deal with radiation from the decay of resonances. This extension is fully general (i.e. it can be applied in principle to any process considered in the zero width limit), and is here applied for the first time. In ordermoreto perform a realistic simulation, we introduce finite width effects using different approximations, that we validated by comparing with published exact NLO results. We have interfaced our POWHEG code to the PYTHIA8 shower Monte Carlo generator. At this stage, we dealt with novel issues related to the treatment of resonances, especially with regard to the initial scale for the shower that needs to be set appropriately. This procedure affects, for example, the fragmentation function of the b quark, that we have studied with particular attention. We believe that the tool presented here improves over previous generators for all aspects that have to do with top decays, and especially for the study of issues related to top mass measurements that involve B hadrons or b jets. The work presented here also constitutes a first step towards a fully consistent matching of NLO calculations involving intermediate resonances decaying into coloured particles, with parton showers.less
Measurement of the Top Quark Mass Simultaneously in Dilepton and Lepton + Jets Decay Channels
Fedorko, Wojciech T.
2008-12-01
The authors present the first measurement of the top quark mass using simultaneously data from two decay channels. They use a data sample of √s = 1.96 TeV collisions with integrated luminosity of 1.9 fb^{-1} collected by the CDF II detector. They select dilepton and lepton + jets channel decays of t$\\bar{t}$ pairs and reconstruct two observables in each topology. They use non-parametric techniques to derive probability density functions from simulated signal and background samples. The observables are the reconstructed top quark mass and the scalar sum of transverse energy of the event in the dilepton topology and the reconstructed top quark mass and the invariant mass of jets from the W boson decay in lepton + jets channel. They perform a simultaneous fit for the top quark mass and the jet energy scale which is constrained in situ by the hadronic W boson resonance from the lepton + jets channel. Using 144 dilepton candidate events and 332 lepton + jets candidate events they measure: M_{top} = 171.9 ± 1.7 (stat. + JES) ± 1.1 (other sys.) GeV/c^{2} = 171.9 ± 2.0 GeV/c^{2}. The measurement features a robust treatment of the systematic uncertainties, correlated between the two channels and develops techniques for a future top quark mass measurement simultaneously in all decay channels. Measurements of the W boson mass and the top quark mass provide a constraint on the mass of the yet unobserved Higgs boson. The Higgs boson mass implied by measurement presented here is higher than Higgs boson mass implied by previously published, most precise CDF measurements of the top quark mass in lepton + jets and dilepton channels separately.
Voltage regulation in linear induction accelerators
Parsons, William M.
1992-01-01
Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.
Voltage regulation in linear induction accelerators
Parsons, W.M.
1992-12-29
Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.
Numerical simulation of linear fiction welding (LFW) processes
Fratini, L.; La Spisa, D. [University of Palermo-Dept. of Industrial engineering (Italy)
2011-05-04
Solid state welding processes are becoming increasingly important due to a large number of advantages related to joining ''unweldable'' materials and in particular light weight alloys. Linear friction welding (LFW) has been used successfully to bond non-axisymmetric components of a range of materials including titanium alloys, steels, aluminum alloys, nickel, copper, and also dissimilar material combinations. The technique is useful in the research of quality of the joints and in reducing costs of components and parts of the aeronautic and automotive industries.LFW involves parts to be welded through the relative reciprocating motion of two components under an axial force. In such process the heat source is given by the frictional forces work decaying into heat determining a local softening of the material and proper bonding conditions due to both the temperature increase and the local pressure of the two edges to be welded. This paper is a comparative test between the numerical model in two dimensions, i.e. in plane strain conditions, and in three dimensions of a LFW process of AISI1045 steel specimens. It must be observed that the 3D model assures a faithful simulation of the actual threedimensional material flow, even if the two-dimensional simulation computational times are very short, a few hours instead of several ones as the 3D model. The obtained results were compared with experimental values found out in the scientific literature.
Giunti, Carlo; Laveder, Marco [INFN, Sezione di Torino, Via P. Giuria 1, I-10125 Torino (Italy); Dipartimento di Fisica G. Galilei, Universita di Padova, and INFN, Sezione di Padova, Via F. Marzolo 8, I-35131 Padova (Italy)
2010-09-01
We consider the interpretation of the MiniBooNE low-energy anomaly and the gallium radioactive source experiments anomaly in terms of short-baseline electron neutrino disappearance in the framework of 3+1 four-neutrino mixing schemes. The separate fits of MiniBooNE and gallium data are highly compatible, with close best-fit values of the effective oscillation parameters {Delta}m{sup 2} and sin{sup 2}2{theta}. The combined fit gives {Delta}m{sup 2}(greater-or-similar sign)0.1 eV{sup 2} and 0.11(less-or-similar sign)sin{sup 2}2{theta}(less-or-similar sign)0.48 at 2{sigma}. We consider also the data of the Bugey and Chooz reactor antineutrino oscillation experiments and the limits on the effective electron antineutrino mass in {beta} decay obtained in the Mainz and Troitsk tritium experiments. The fit of the data of these experiments limits the value of sin{sup 2}2{theta} below 0.10 at 2{sigma}. Considering the tension between the neutrino MiniBooNE and gallium data and the antineutrino reactor and tritium data as a statistical fluctuation, we perform a combined fit which gives {Delta}m{sup 2}{approx_equal}2 eV and 0.01(less-or-similar sign)sin{sup 2}2{theta}(less-or-similar sign)0.13 at 2{sigma}. Assuming a hierarchy of masses m{sub 1}, m{sub 2}, m{sub 3}<
Verhoef, L.A.; Stroom, J.C.; Bisschop, F.J.; Liefting, J.R.; Sinke, W.C. )
1990-12-15
In modern production schemes for Si solar cells, defect passivation and impurity gettering are often used to improve material quality and thereby cell efficiency. These processes generally alter the spatial uniformity of minority-carrier transport parameters over the wafer and may result in minority-carrier lifetime and diffusion length variations both lateral and in depth. In polycrystalline Si these spatial dependences are already present due to the nature of the material. We present an extension of the photocurrent decay method to determine the diffusion length in a three-dimensionally resolved fashion. From a single photocurrent decay curve the back-surface recombination velocity, the average minority-carrier diffusion length, and an asymmetry factor which qualitatively describes the depth dependence of the diffusion length are determined. This is done using the three observables: quantum efficiency, fundamental decay time, and intercept of the extrapolated decay curve with the time-zero axis. Lateral resolution is obtained by focusing the light beam to a small spot on the cell and measuring the current decay curve as a function of position on the cell. It is shown that light-pulse durations longer than the minority-carrier lifetime and wavelengths longer than 950 nm are required. These conditions are met by using modulated wavelength-tunable light from a Ti:sapphire laser. Measurements on monocrystalline cells show that the decay time is independent of wavelength and light-pulse duration, as predicted by theory. Furthermore, the intercept with the time-zero axis was shown to increase with increasing pulse duration and wavelength. Measurements on a set of polycrystalline Si cells were performed showing that gettering treatments during cell production result in depth-dependent lifetimes.
Influence of anharmonic phonon decay on self-heating in Si nanowire transistors
Rhyner, Reto Luisier, Mathieu
2014-08-11
Anharmonic phonon-phonon scattering is incorporated into an electro-thermal quantum transport approach based on the nonequilibrium Green's function formalism. Electron-phonon and phonon-phonon interactions are taken into account through scattering self-energies solved in the self-consistent Born approximation. While studying self-heating effects in ultra-scaled Si nanowire transistors, it is found that the phonon decay process softens the artificial accumulation of high energy phonons caused by electron relaxations close to the drain region. This leads to an increase of the device current in the ON-state and a reduction of the effective lattice temperature.
S-wave K- pi+ system in D+ ---> K- pi+ pi+ decays from Fermilab E791
Meadows, B.T.; /Cincinnati U.
2005-06-01
A new approach to the analysis of three body decays is presented. Model-independent results are obtained for the S-wave K{pi} amplitude as a function of K{pi} invariant mass. These are compared with results from K{sup -}{pi}{sup +} elastic scattering, and the prediction of the Watson theorem, that the phase behavior be the same below K{eta}' threshold, is tested. Contributions from I = 1/2 and I = 3/2 are not resolved in this study. If I = 1/2 dominates, however, the Watson theorem does not describe these data well.
A comparison of parametric decay of oblique Langmuir wave in high and low density magneto-plasmas
Shahid, M.; Hussain, A.; Department of Physics, Government College University, Lahore-54000 ; Murtaza, G.
2013-09-15
The parametric decay instability of an obliquely propagating Langmuir wave into the low-frequency electromagnetic shear Alfven wave and the Left-Handed Circularly Polarized wave has been investigated in an electron-ion plasma, immersed in a uniform external magnetic field. Quantum magneto-hydrodynamic model has been used to find the linear and non-linear response of a high density quantum magneto-plasma. Going to the classical limit (??0) retrieves the results for low density classical plasma. Nonlinear dispersion relations and growth rates are derived with analytically and numerically. It is observed that growth rate in the high density degenerate magneto-plasma increases exponentially, while in the low density classical case it increases logarithmically.
Optically isolated signal coupler with linear response
Kronberg, James W.
1994-01-01
An optocoupler for isolating electrical signals that translates an electrical input signal linearly to an electrical output signal. The optocoupler comprises a light emitter, a light receiver, and a light transmitting medium. The light emitter, preferably a blue, silicon carbide LED, is of the type that provides linear, electro-optical conversion of electrical signals within a narrow wavelength range. Correspondingly, the light receiver, which converts light signals to electrical signals and is preferably a cadmium sulfide photoconductor, is linearly responsive to light signals within substantially the same wavelength range as the blue LED.
International Workshop on Linear Colliders 2010
None
2016-07-12
IWLC2010 International Workshop on Linear Colliders 2010ECFA-CLIC-ILC joint meeting: Monday 18 October - Friday 22 October 2010Venue: CERN and CICG (International Conference Centre Geneva, Switzerland)Â This year, the International Workshop on Linear Colliders organized by the European Committee for Future Accelerators (ECFA) will study the physics, detectors and accelerator complex of a linear collider covering both CLIC and ILC options.Contact Workshop SecretariatÂ Â IWLC2010 is hostedÂ by CERN
What can we learn from neutrinoless double beta decay experiments? (Journal
Office of Scientific and Technical Information (OSTI)
Article) | SciTech Connect What can we learn from neutrinoless double beta decay experiments? Citation Details In-Document Search Title: What can we learn from neutrinoless double beta decay experiments? We assess how well next generation neutrinoless double beta decay and normal neutrino beta decay experiments can answer four fundamental questions. 1) If neutrinoless double beta decay searches do not detect a signal, and if the spectrum is known to be inverted hierarchy, can we conclude
Measurement of Branching Fractions of B0 Decays to K1(1270)+ pi- and K1(1400)+ pi-
Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, Antimo; Pappagallo, M.; Eigen, G.; Stugu, Bjarne; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, Robert N.; Jacobsen, R.G.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Banca di Roma /Frascati /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison
2008-08-04
We present a measurement of the branching fraction of neutral B meson decaying to final states containing a K1 meson, i.e. K{sub 1}(1270) and K{sub 1}(1400), and a charged pion. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 454 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation. We measure the branching fraction {Beta}(B{sup 0} {yields} K{sub 1}{sup +}{pi}{sup -}) = (31.0 {+-} 2.7 {+-} 6.9) x 10{sup -6}, where the first error quoted is statistical and the second is systematic. In the framework of the K-matrix formalism used to describe these decays, we also set limits on the ratio of the production constants for the K{sub 1}(1270){sup +} and K{sub 1}(1400){sup +} mesons in B{sup 0} decays.
Search for baryon number violation in top-quark decays
Chatrchyan, Serguei
2014-02-20
A search for baryon number violation (BNV) in top-quark decays is performed using pp collisions produced by the LHC at sqrt(s) = 8 TeV. The top-quark decay considered in this search results in one light lepton (muon or electron), two jets, but no neutrino in the final state. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.5 inverse femtobarns. The event selection is optimized for top quarks produced in pairs, with one undergoing the BNV decay and the other the standard model hadronic decay to three jets. No significant excessmore » of events over the expected yield from standard model processes is observed. The upper limits at 95% confidence level on the branching fraction of the BNV top-quark decay are calculated to be 0.0016 and 0.0017 for the muon and the electron channels, respectively. Assuming lepton universality, an upper limit of 0.0015 results from the combination of the two channels. These limits are the first that have been obtained on a BNV process involving the top quark.« less
Nuclear Properties and Decay Data Chart of Nuclides.
Energy Science and Technology Software Center (OSTI)
2008-04-04
Version 00 NUCHART displays nuclear decay data graphically on a PC and, includes a search routine for assigning gamma-ray energies to radionuclides. The numerical data included in NUCHART were taken from the online database "NUDAT" Version of March 1994. The following information is presented: (1) Nuclide information: for each nuclide, abundance, mass excess, (main) decay mode, half-life and uncertainty, branching ratio, decay Q; (2) decay radiation: for each nuclide, tables of radiation energy, intensity andmore » equivalent dose for the 5 most intense decay radiations of beta+, beta-, conversion electrons, gammas, alphas and x-rays, including electron Augers; (3) adopted gammas: for each nuclide, table containing energy, relative intensity, energy level of the main gamma lines and year of publication in Nuclear Data Sheets; (4) search gamma energies: for a specified interval of gamma energies all know gamma lines and their nuclides are displayed; the database contains 132,000 gamma lines; (5) a search mode by specific nuclide is also available. For the latest data and online tools for viewing the data, see NuDat 2.4 on the NNDC and IAEA NDS websites: http://www.nndc.bnl.gov/ and http://www-nds.iaea.org/.« less
Status of the SLC (Stanford Linear Collider)
Coupal, D.P.
1989-07-01
This report presents a brief review of the status of the Stanford Linear Collider. Topics covered are: Beam luminosity, Detectors and backgrounds; and Future prospects. 3 refs., 8 figs., 1 tab. (LSP)
FPGA-based Klystron linearization implementations in scope of ILC
Omet, M.; Michizono, S.; Varghese, P.; Schlarb, H.; Branlard, J.; Cichalewski, W.
2015-01-23
We report the development and implementation of four FPGA-based predistortion-type klystron linearization algorithms. Klystron linearization is essential for the realization of ILC, since it is required to operate the klystrons 7% in power below their saturation. The work presented was performed in international collaborations at the Fermi National Accelerator Laboratory (FNAL), USA and the Deutsches Elektronen Synchrotron (DESY), Germany. With the newly developed algorithms, the generation of correction factors on the FPGA was improved compared to past algorithms, avoiding quantization and decreasing memory requirements. At FNAL, three algorithms were tested at the Advanced Superconducting Test Accelerator (ASTA), demonstrating a successful implementation for one algorithm and a proof of principle for two algorithms. Furthermore, the functionality of the algorithm implemented at DESY was demonstrated successfully in a simulation.
FPGA-based Klystron linearization implementations in scope of ILC
Omet, M.; Michizono, S.; Matsumoto, T.; Miura, T.; Qiu, F.; Chase, B.; Varghese, P.; Schlarb, H.; Branlard, J.; Cichalewski, W.
2015-01-23
We report the development and implementation of four FPGA-based predistortion-type klystron linearization algorithms. Klystron linearization is essential for the realization of ILC, since it is required to operate the klystrons 7% in power below their saturation. The work presented was performed in international collaborations at the Fermi National Accelerator Laboratory (FNAL), USA and the Deutsches Elektronen Synchrotron (DESY), Germany. With the newly developed algorithms, the generation of correction factors on the FPGA was improved compared to past algorithms, avoiding quantization and decreasing memory requirements. At FNAL, three algorithms were tested at the Advanced Superconducting Test Accelerator (ASTA), demonstrating a successfulmore » implementation for one algorithm and a proof of principle for two algorithms. Furthermore, the functionality of the algorithm implemented at DESY was demonstrated successfully in a simulation.« less
Randomized Linear Algebra for BioImaging
U.S. Department of Energy (DOE) all webpages (Extended Search)
Randomized Linear Algebra for BioImaging Randomized Linear Algebra for BioImaging Mass-Spectrometry Imaging Mass spectrometry measures ions derived from the molecules present in a biological sample. Spectra of the ions are acquired at each location (pixel) of a sample, allowing for the collection of spatially resolved mass spectra. This mode of analysis is known as mass spectrometry imaging (MSI). The addition of ion-mobility separation (IMS) to MSI adds another dimension, drift time. The
Evidence for the decay X(3872) -> J/\\psi\\omega
del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison
2011-08-11
We present a study of the decays B{sup 0,+} --> J/{psi}{pi}{sup +}{pi}{sup -}{pi}{sup 0}K{sup 0,+}, using 467x10{sup 6} B{anti B} pairs recorded with the BABAR detector. We present evidence for the decay mode X(3872) --> J/{psi}{omega}, with product branching fractions B(B{sup +} --> X(3872)K{sup +}) x B(X(3872) --> J/{psi}{omega}) = [0.6 {+-} 0.2(stat) {+-} 0.1(syst)] x 10{sup -5}, and B(B{sup 0} --> X(3872)K{sup 0}) x B(X(3872) --> J/{psi}{omega}) = [0.6 {+-} 0.3(stat) {+-} 0.1(syst)] x 10{sup -5}. A detailed study of the {pi}{sup +}{pi}{sup -}{pi}{sup 0} mass distribution from X(3872) decay favors a negative-parity assignment.
Double beta decay, Majorana neutrinos, and neutrino mass
Avignone, Frank T. III; Elliott, Steven R.; Engel, Jonathan [Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599-3255 (United States)
2008-04-15
The theoretical and experimental issues relevant to neutrinoless double beta decay are reviewed. The impact that a direct observation of this exotic process would have on elementary particle physics, nuclear physics, astrophysics, and cosmology is profound. Now that neutrinos are known to have mass and experiments are becoming more sensitive, even the nonobservation of neutrinoless double beta decay will be useful. If the process is actually observed, we will immediately learn much about the neutrino. The status and discovery potential of proposed experiments are reviewed in this context, with significant emphasis on proposals favored by recent panel reviews. The importance of and challenges in the calculation of nuclear matrix elements that govern the decay are considered in detail. The increasing sensitivity of experiments and improvements in nuclear theory make the future exciting for this field at the interface of nuclear and particle physics.
Chiral Two-body Currents and Neutrinoless Double Beta Decay
Menendez, Javier [Institut fuer Kernphysik, Technische Universitaet Darmstadt, 64289 Darmstadt (Germany); ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany)
2011-12-16
The nuclear matrix elements (NMEs) of neutrinoless double-beta (0{nu}{beta}{beta}) decay are studied using weak currents derived in the framework of chiral effective field theory. Apart from the standard one-body (1b) currents, it is shown that two-body (2b) currents contribute to weak processes. The normal-ordered 1b part of 2b currents modifies the Gamow-Teller (GT){sigma}{tau}{sup -} part of the 1b current, contributing to the well-known quenching of GT single-{beta} decays. The momentum-transfer dependence of the quenching due to 2b currents is also predicted. Therefore, including 2b currents allows to address, microscopically, the problem of the axial weak coupling (g{sub A}) value, which is the biggest uncertainty in the 0{nu}{beta}{beta} decay NME calculations for all available methods.
Results of the double beta decay experiment NEMO-3
Tretyak, V. I. [Joint Institute for Nuclear Research, 6 Joliot Curie, Dubna (Russian Federation); Collaboration: NEMO-3 Collaboration
2013-12-30
The double beta decay experiment NEMO-3 has taken data from February 2003 to January 2011. The two-neutrino decay half lives were measured for seven different isotopes ({sup 100}Mo, {sup 82}Se, {sup 116}Cd, {sup 150}Nd, {sup 96}Zr, {sup 48}Ca and {sup 130}Te). No evidence for neutrinoless double beta decay is observed. The 0??? half-life limits are found to be T{sub 1/2}{sup 0?}({sup 100}Mo)>1.010{sup 24}yr(90%C.L.) and T{sub 1/2}{sup 0?}({sup 82}Se)>3.210{sup 23}yr(90%C.L.)
Precision Measurements of Tau Lepton Decays
Nugent, Ian M.; /Victoria U.
2010-03-16
Using data collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy near 10.58 GeV, the branching fractions {Beta}({tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}) = (8.83 {+-} 0.01 {+-} 0.13)%, {Beta}({tau}{sup -} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}) = (0.273 {+-} 0.002 {+-} 0.009)%, {Beta}({tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}}) = (0.1346 {+-} 0.0010 {+-} 0.0036)%, and {Beta}({tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}}) = (1.58 {+-} 0.13 {+-} 0.12) x 10{sup -5} are measured where the uncertainties are statistical and systematic, respectively. The invariant mass distribution for the {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}, {tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}} and {tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}} decays are unfolded to correct for detector effects. A measurement of {Beta}({tau}{sup -} {yields} {phi}{pi}{sup -}{nu}{sub {tau}}) = (3.42 {+-} 0.55 {+-} 0.25) x 10{sup -5}, a measurement of {Beta}({tau}{sup -} {yields} {phi}K{sup -}{nu}{sub {tau}}) = (3.39 {+-} 0.20 {+-} 0.28) x 10{sup -5} and an upper limit on {Beta}({tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}}[ex.{phi}]) {le} 2.5 x 10{sup -6} {at} 905 CL are determined from a binned maximum likelihood fit of the {tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}} and {tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}} K{sup +}K{sup -} invariant mass distributions. The branching ratio {Beta}({tau}{sup -} {yields} K{sup -}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} {pi}{sup -}{nu}{sub {tau}}) is measured to be (6.531 {+-} 0.056 {+-} 0.093) x 10{sup -2} from which |V{sub us}| is determined to be 0.2255 {+-} 0.0023. The branching ratio {Beta}/({tau}{sup -} {yields} {mu}{nu}{sub {tau}}{bar {nu
Systematics of the α-decay fine structure in even–even nuclei
Delion, D.S.; Dumitrescu, A.
2015-01-15
We describe α-transitions to low-lying states in even–even nuclei with Z>50,N>82 using the Coherent State Model (CSM). We reproduce the energy levels and electromagnetic transition rates between the states of the ground band employing two parameters, namely the deformation parameter and the strength of the harmonic CSM Hamiltonian. The B(E2) values are described in terms of an effective charge which depends linearly on the deformation parameter. The treatment of the α-emission process is based on an α–daughter interaction containing a monopole component, calculated through a double folding procedure with a M3Y interaction plus a repulsive core simulating the Pauli principle, and a quadrupole–quadrupole (QQ) interaction. The decaying states are identified with the lowest narrow outgoing resonances obtained through the coupled channels method. The α-branching ratios to 2{sup +} states are reproduced by means of the QQ strength. This interaction strength can be fitted with a linear dependence on the deformation parameter, as predicted by the CSM. The theoretical intensities to 4{sup +} and 6{sup +} states are in reasonable agreement with available experimental data. Predictions are made for spherical, transitional and well deformed even–even α-emitters.
Dilatometric measurements of helium densities in bubbles arising from tritium decay in tantalum
Schober, T.; Lasser, R.; Golczewski, J.; Dieker, C.; Trinkaus, H.
1985-06-01
The swelling rates of the bulk tritides TaT/sub 0.42/ and TaT/sub 0.103/ were measured at room temperature using the technique of strain gauges. Such swelling is expected in tritides because of the decay of tritium to /sup 3/He and the subsequent precipitation of gas bubbles. Observations were made for up to 10 months. Almost-linear swelling was found in the first months for both tritides, indicative of a constant /sup 3/He density in the bubbles. The slopes of the linear parts of the expansion curves normalized to the T concentration were almost identical in the two cases considered. From this a /sup 3/He-to-Ta atom volume ratio, v/sub He//..cap omega..< or =0.52 +- 0.03 in the bubbles was derived, which is in good agreement with recent but less direct spectroscopic measurements of /sup 4/He densities in bubbles formed after room-temperature implantation into other metals. Corrections for the presence of self-interstitials and their clusters and due to the elastic relaxation of the bubbles were considered. Calculated bubble pressures were in the vicinity of 5 GPa, which is close to the expected threshold pressure for athermal bubble growth.
{phi} meson radiative decays to {eta} and {eta}'
Ambrosino, F.
2006-02-11
We present recent results from KLOE on the dynamics of {eta} {yields} {pi}{pi}{pi} decays, as well as searches for rare {eta} decays, including a new determination of the {eta} {yields} {pi}0{gamma}{gamma} Branching Ratio. We also present a preliminary result on the ratio BR({phi} {yields} {eta}'{gamma})/BR({phi} {yields} {eta}{gamma}), a quantity related to the {eta} - {eta}' mixing and the gluonium content of the {eta}'. All results are obtained from the analysis of 450 pb-1 integrated luminosity from 2001-2002 runs.
OSTIblog Articles in the neutrinos Neutrinoless Double Beta Decay Topic |
Office of Scientific and Technical Information (OSTI)
OSTI, US Dept of Energy Office of Scientific and Technical Information Neutrinoless Double Beta Decay Topic Mining for Gold, Neutrinos and the Neutrinoless Double Beta Decay by Kathy Chambers 23 Sep, 2014 in Deep within the caverns of Lead, South Dakota is one of the nation's preeminent underground laboratories. The site of the former Homestake Mine was once one of the largest and deepest gold mines in North America. This famous mine was discovered during the 1876 Black Hills gold rush and
Rare Decays And Exotic States With BaBar
Robertson, S.H.; /McGill U.
2006-08-28
Results from the BABAR experiment are presented for searches for several rare FCNC B and D meson decays, including the modes B{sup 0} {yields} {ell}{sup +}{ell}{sup -} and D{sup 0} {yields} {ell}{sup +}{ell}{sup -}, B {yields} ({rho},{omega}){gamma} and B{sup +} {yields} (K,{pi}){sup +}{nu}{bar {nu}}. Limits on lepton flavor violation in neutrino-less {tau} decays are also discussed. Finally, results of BABAR searches for the strange pentaquark states {Theta}{sup +}(1540), {Xi}{sup --}(1860) and {Xi}{sup 0}(1860) are summarized.
Selected spectroscopic results on element 115 decay chains
Rudolph, D.; Forsberg, U.; Golubev, P.; Sarmiento, L. G.; Yakushev, A.; Andersson, L. -L.; Di Nitto, A.; Düllmann, Ch. E.; Gates, J. M.; Gregorich, K. E.; et al
2014-08-24
We observed thirty correlated α-decay chains in an experiment studying the fusion-evaporation reaction 48Ca + 243Am at the GSI Helmholtzzentrum fur Schwerionenforschung. The decay characteristics of the majority of these 30 chains are consistent with previous observations and interpretations of such chains to originate from isotopes of element Z = 115. High-resolution α-photon coincidence spectroscopy in conjunction with comprehensive Monte-Carlo simulations allow to propose excitation schemes of atomic nuclei of the heaviest elements, thereby probing nuclear structure models near the 'Island of Stability' with unprecedented experimental precision.
Selected spectroscopic results on element 115 decay chains
Rudolph, D.; Forsberg, U.; Golubev, P.; Sarmiento, L. G.; Yakushev, A.; Andersson, L. -L.; Di Nitto, A.; Düllmann, Ch. E.; Gates, J. M.; Gregorich, K. E.; Gross, C. J.; Herzberg, R. -D.; Heßberger, F. P.; Khuyagbaatar, J.; Kratz, J. V.; Rykaczewski, K.; Schädel, M.; Åberg, S.; Ackermann, D.; Block, M.; Brand, H.; Carlsson, B. G.; Cox, D.; Derkx, X.; Eberhardt, K.; Even, J.; Fahlander, C.; Gerl, J.; Jäger, E.; Kindler, B.; Krier, J.; Kojouharov, I.; Kurz, N.; Lommel, B.; Mistry, A.; Mokry, C.; Nitsche, H.; Omtvedt, J. P.; Papadakis, P.; Ragnarsson, I.; Runke, J.; Schaffner, H.; Schausten, B.; Thörle-Pospiech, P.; Torres, T.; Traut, T.; Trautmann, N.; Türler, A.; Ward, A.; Ward, D. E.; Wiehl, N.
2014-08-24
We observed thirty correlated α-decay chains in an experiment studying the fusion-evaporation reaction ^{48}Ca + ^{243}Am at the GSI Helmholtzzentrum fur Schwerionenforschung. The decay characteristics of the majority of these 30 chains are consistent with previous observations and interpretations of such chains to originate from isotopes of element Z = 115. High-resolution α-photon coincidence spectroscopy in conjunction with comprehensive Monte-Carlo simulations allow to propose excitation schemes of atomic nuclei of the heaviest elements, thereby probing nuclear structure models near the 'Island of Stability' with unprecedented experimental precision.
The Half Life of {sup 193}Osbeta-decay
Zahn, Guilherme S.; Genezini, Frederico A.; Oliva, Jefferson W. M.; Zamboni, Cibele B.
2010-05-21
In this work, the half life of the beta{sup -} decay of {sup 193}Os was measured by following the activity of 25 5 mg {sup 192}Os-enriched samples for 20-60 h after they were irradiated in the IEA-R1 reactor of IPEN-CNEN/SP. Three different transitions associated with this beta decay were analyzed, and the results were then processed using three different statistical methods; the resulting values were compatible with the tabulated value, with an uncertainty of the same order of magnitude.
New Limit on Time-Reversal Violation in Beta Decay
Mumm, H. P.; Chupp, T. E.; Cooper, R. L.; Coulter, K. P.; Freedman, S. J.; Fujikawa, B. K.; Garcia, A.; Jones, G. L.; Nico, J. S.; Thompson, A. K.; Trull, C. A.; Wietfeldt, F. E.; Wilkerson, J. F.
2011-09-02
We report the results of an improved determination of the triple correlation DP{center_dot}(p{sub e}xp{sub v}) that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to the standard model. Our result is D=[-0.96{+-}1.89(stat){+-}1.01(sys)]x10{sup -4}. The corresponding phase between g{sub A} and g{sub V} is {phi}{sub AV}=180.013 deg. {+-}0.028 deg. (68% confidence level). This result represents the most sensitive measurement of D in nuclear {beta} decay.
{alpha} decay of {sup 180,181}Pb
Andreyev, A. N.; Antalic, S.; Saro, S.; Ackermann, D.; Comas, V. F.; Heinz, S.; Heredia, J. A.; Hessberger, F. P.; Khuyagbaatar, J.; Kojouharov, I.; Kindler, B.; Lommel, B.; Mann, R.; Cocolios, T. E.; Elseviers, J.; Huyse, M.; Duppen, P. Van; Venhart, M.; Franchoo, S.; Hofmann, S.
2009-11-15
A detailed {alpha}-decay study of the neutron-deficient isotope {sup 181}Pb has been performed in the complete fusion reaction {sup 40}Ca+{sup 144}Sm{yields}{sup 184}Pb* at the velocity filter SHIP (GSI, Darmstadt). In comparison with the literature, more precise data have been deduced for the I{sup {pi}}=(9/2{sup -}) ground state in this nucleus, which is presumably based on the neutron {nu}h{sub 9/2} spherical orbital. Improved {alpha}-decay data were also measured for {sup 180}Pb.
The GERDA Neutrinoless Double Beta-Decay Experiment
Majorovits, Bela A. [Max Planck Institut fuer Physik, Foehringer Ring 6, 80805 Munich (Germany)
2007-10-12
Neutrinoless double beta (0{nu}{beta}{beta})-decay is the key process to gain understanding of the nature of neutrinos. The GErmanium Detector Array (GERDA) is designed to search for 0{nu}{beta}{beta}-decay of the isotope {sup 76}Ge. Germanium crystals enriched in {sup 76}Ge, acting as source and detector simultaneously, will be submerged directly into an ultra pure cooling medium that also serves as a radiation shield. This concept will allow for a reduction of the background by up to two orders of magnitudes with respect to earlier experiments.
Double-{beta} decay Q value of {sup 150}Nd
Kolhinen, V. S.; Eronen, T.; Gorelov, D.; Hakala, J.; Jokinen, A.; Kankainen, A.; Moore, I. D.; Rissanen, J.; Saastamoinen, A.; Suhonen, J.; Aeystoe, J. [Department of Physics, P. O. Box 35 (YFL), FI-40014 University of Jyvaeskylae (Finland)
2010-08-15
The double-{beta} decay Q value of {sup 150}Nd was determined by using the JYFLTRAP Penning trap mass spectrometer. The measured mass difference between {sup 150}Nd and {sup 150}Sm is 3371.38(20) keV. This new value deviates by 3.7 keV from the previously adopted value of 3367.7(22) keV and is a factor of 10 more precise. Accurate knowledge of this Q value is important because {sup 150}Nd is a primary candidate to be used in the search for neutrinoless double-{beta} decay modes in several experiments.
Consistency test of neutrinoless double beta decay with one isotope
Duerr, Michael; Lindner, Manfred [Max-Planck-Institut fuer Kernphysik, Postfach 10 39 80, 69029 Heidelberg (Germany); Zuber, Kai [Technical University Dresden, Institut fuer Kern- und Teilchenphysik, 01069 Dresden (Germany)
2011-11-01
We discuss a consistency test which makes it possible to discriminate unknown nuclear background lines from neutrinoless double beta decay with only one isotope. By considering both the transition to the ground state and to the first excited 0{sup +} state, a sufficiently large detector can reveal if neutrinoless double beta decay or some other nuclear physics process is at work. Such a detector could therefore simultaneously provide a consistency test for a certain range of Majorana masses and be sensitive to lower values of the effective Majorana mass
Time-resolved fluorescence decay measurements for flowing particles
Deka, Chiranjit; Steinkamp, John A.
1999-01-01
Time-resolved fluorescence decay measurements for flowing particles. An apparatus and method for the measurement and analysis of fluorescence for individual cells and particles in flow are described, wherein the rapid measurement capabilities of flow cytometry and the robust measurement and analysis procedures of time-domain fluorescence lifetime spectroscopy are combined. A pulse-modulated cw laser is employed for excitation of the particles. The characteristics and the repetition rate of the excitation pulses can be readily adjusted to accommodate for fluorescence decays having a wide range of lifetimes.
Time-resolved fluorescence decay measurements for flowing particles
Deka, C.; Steinkamp, J.A.
1999-06-01
Time-resolved fluorescence decay measurements are disclosed for flowing particles. An apparatus and method for the measurement and analysis of fluorescence for individual cells and particles in flow are described, wherein the rapid measurement capabilities of flow cytometry and the robust measurement and analysis procedures of time-domain fluorescence lifetime spectroscopy are combined. A pulse-modulated CW laser is employed for excitation of the particles. The characteristics and the repetition rate of the excitation pulses can be readily adjusted to accommodate for fluorescence decays having a wide range of lifetimes. 12 figs.
Improved estimates of rare K decay matrix elements from K{sub l3} decays
Mescia, Federico; Smith, Christopher
2007-08-01
The estimation of rare K decay matrix elements from K{sub l3} experimental data is extended beyond LO in chiral perturbation theory. Isospin-breaking effects at next-to-leading order (and partially next-to-next-to-leading order) in the chiral perturbation theory expansion, as well as QED radiative corrections, are now accounted for. The analysis relies mainly on the cleanness of two specific ratios of form factors, for which the theoretical control is excellent. As a result, the uncertainties on the K{sup +}{yields}{pi}{sup +}{nu}{nu} and K{sub L}{yields}{pi}{sup 0}{nu}{nu} matrix elements are reduced by a factor of about 7 and 4, respectively, and similarly for the direct CP-violating contributions to K{sub L}{yields}{pi}{sup 0}e{sup +}e{sup -} and K{sub L}{yields}{pi}{sup 0}{mu}{sup +}{mu}{sup -}. They could be reduced even further with better experimental data for the K{sub l3} slopes and the K{sub l3}{sup +} branching ratios. As a result, the nonparametric errors for B(K{yields}{pi}{nu}{nu}) and for the direct CP-violating contributions to B(K{sub L}{yields}{pi}{sup 0}l{sup +}l{sup -}) are now completely dominated by those on the short-distance physics.
Enhanced γ -Ray Emission from Neutron Unbound States Populated in β Decay
Tain, J. L.; Valencia, E.; Algora, A.; Agramunt, J.; Rubio, B.; Rice, S.; Gelletly, W.; Regan, P.; Zakari-Issoufou, A. -A.; Fallot, M.; et al
2015-08-01
Total absorption spectroscopy was used to investigate the β -decay intensity to states above the neutron separation energy followed by γ -ray emission in 87,88Br and 94Rb. Accurate results were obtained thanks to the careful control of systematic errors. An unexpectedly large γ intensity was observed in all three cases extending well beyond the excitation energy region where neutron penetration is hindered by low neutron energy. The γ branching as a function of excitation energy was compared to Hauser-Feshbach model calculations. For 87Br and 88Br the branching reaches 57% and 20% respectively, and could be explained as a nuclear structuremore » effect. Some of the states populated in the daughter can only decay through the emission of a large orbital angular momentum neutron with a strongly reduced barrier penetrability. In the case of neutron-rich 94Rb the observed 4.5% branching is much larger than the calculations performed with standard nuclear statistical model parameters, even after proper correction for fluctuation effects on individual transition widths. The difference can be reconciled introducing an enhancement of one order-of-magnitude in the photon strength to neutron strength ratio. An increase in the photon strength function of such magnitude for very neutron-rich nuclei, if it proved to be correct, leads to a similar increase in the (n, γ) cross section that would have an impact on r process abundance calculations.« less
Not Available
1992-07-01
This appendix presents the results of decay calculations using the ORIGEN2 code to determine the radiological properties of canisters of immobilized high-level waste as a function of decay time for decay times up to one million years. These calculations were made for the four HLW sites (West Valley Demonstration Project, Savannah River Site, Hanford Site, and Idaho National Engineering Laboratory) using the composition data discussed in the HLW section of this report. Calculated ({alpha},n) neutron production rates are also shown.
TURBULENCE DECAY AND CLOUD CORE RELAXATION IN MOLECULAR CLOUDS
Gao, Yang; Law, Chung K.; Xu, Haitao
2015-02-01
The turbulent motion within molecular clouds is a key factor controlling star formation. Turbulence supports molecular cloud cores from evolving to gravitational collapse and hence sets a lower bound on the size of molecular cloud cores in which star formation can occur. On the other hand, without a continuous external energy source maintaining the turbulence, such as in molecular clouds, the turbulence decays with an energy dissipation time comparable to the dynamic timescale of clouds, which could change the size limits obtained from Jean's criterion by assuming constant turbulence intensities. Here we adopt scaling relations of physical variables in decaying turbulence to analyze its specific effects on the formation of stars. We find that the decay of turbulence provides an additional approach for Jeans' criterion to be achieved, after which gravitational infall governs the motion of the cloud core. This epoch of turbulence decay is defined as cloud core relaxation. The existence of cloud core relaxation provides a more complete understanding of the effect of the competition between turbulence and gravity on the dynamics of molecular cloud cores and star formation.
Decay heat fractions for DFA 8213 and 4192
Kessler, S.F., Fluor Daniel Hanford
1997-02-06
Decay heat fractions for FFTF driver fuel assemblies 8213 and 4192 were calculated to allow the assembly nozzles to be cut. Cutting the nozzles is required to allow the assemblies to fit in the center location of a core component container in an Interim Storage Cask.
Consistent scenario for B{yields}PS decays
Delepine, D.; Lucio M, J. L.; Mendoza S, J. A.; Ramirez, Carlos A.
2008-12-01
We consider B{yields}PS decays where P stands for pseudoscalar and S for a heavy (1500 MeV) scalar meson. We achieve agreement with available experimental data, which includes two orders of magnitude hierarchy, assuming the scalars mesons are two quark states. The contribution of the dipolar penguin operator O{sub 11} is quantified.
The Majorana Double Beta Decay Experiment: Present Status
Aguayo, Estanislao; Avignone, Frank T.; Back, Henning O.; Barabash, Alexander S.; Beene, Jim; Bergevin, M.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Chan, Yuen-Dat; Christofferson, C. D.; Collar, J. I.; Combs, Dustin C.; Cooper, R. J.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S. R.; Esterline, James H.; Fast, James E.; Fields, N.; Finnerty, P.; Fraenkle, Florian; Gehman, Victor M.; Giovanetti, G. K.; Green, M. P.; Guiseppe, V. E.; Gusey, K.; Hallin, A. L.; Hazama, R.; Henning, Reyco; Hime, Andrew; Hoppe, Eric W.; Horton, Mark; Howard, Stanley; Howe, M. A.; Johnson, R. A.; Keeter, K.; Keller, C.; Kidd, M. F.; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; Laferriere, Brian D.; LaRoque, B. H.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Mei, Dong-Ming; Merriman, Jason H.; Miller, M. L.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; Overman, Nicole R.; Phillips II, D. G.; Poon, Alan; Perumpilly, Gopakumar; Prior, Gersende; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Steele, David; Strain, J.; Thomas, K.; Timkin, V.; Tornow, W.; Vanyushin, I.; Varner, R. L.; Vetter, Kai; Vorren, Kris R.; Wilkerson, J. F.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir; Zhang, C.
2013-06-01
The Majorana collaboration is actively pursuing research and development aimed at a tonne-scale 76Ge neutrinoless double-beta decay experiment, an R&D effort that will field approximately 40 kg of germanium detectors with mixed enrichment levels. This article provides a status update on the construction of the Demonstrator
Search for a strongly decaying neutral charmed pentaquark
Link, J.M.; Yager, P.M.; Anjos, J.C.; Bediaga, I.; Castromonte, C.; Machado, A.A.; Magnin, J.; Massafferri, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; dos Reis, A.C.; Carrillo, S.; Casimiro, E.; Cuautle, E.; Sanchez-Hernandez, A.; Uribe, C.; Vazquez, F.; Agostino, L.; Cinquini, L.; Cumalat,J.P.; ,
2005-06-01
We present a search for a charmed pentaquark decaying strongly to D{sup (*)}-p. Finding no evidence for such a state, we set limits on the cross section times branching ratio relative to D*{sup -} and D{sup -} under particular assumptions about the production mechanism.
Cosmic rays from leptophilic dark matter decay via kinetic mixing
Ibarra, Alejandro; Tran, David; Ringwald, Andreas; Weniger, Christoph E-mail: andreas.ringwald@desy.de E-mail: christoph.weniger@desy.de
2009-08-01
If interpreted in terms of decaying dark matter, the steep rise in the positron fraction of cosmic rays above 10 GeV, as observed by the PAMELA experiment, suggests an underlying production mechanism that favors leptonic channels. We consider a scenario where a portion of the dark matter is made of the gauginos of an unbroken hidden-sector U(1){sub X}, which interact with the visible sector only through a tiny kinetic mixing. The second component of the dark matter is made of neutralinos, and depending on the mass spectrum, either the lightest neutralino or the hidden gaugino becomes unstable and subject to decay. We analyze the cosmic rays, namely the contributions to the positron, the extragalactic gamma-ray and the antiproton flux, which potentially result from these decays and demonstrate that the production of antiprotons can be naturally suppressed. Furthermore, we briefly discuss the apparent double-peak structure of the ATIC data in light of cascade-decaying hidden gauginos, as well as possible signatures at Fermi.
Searches for massive neutrinos in nuclear beta decay
Jaros, J.A.
1992-10-01
The status of searches for massive neutrinos in nuclear beta decay is reviewed. The claim by an ITEP group that the electron antineutrino mass > 17eV has been disputed by all the subsequent experiments. Current measurements of the tritium beta spectrum limit m[sub [bar [nu
MAJORANA Neutrinoless Double-Beta Decay DUSEL R&D
Wilkerson, John F.
2009-09-04
The Majorana research and development is addressing key issues and risks related to the collaboration's goal of undertaking a search for neutrinoless double-beta decay (0{nu}{beta}{beta}) in {sup 76}Ge using an array of hyper-pure Ge-diodes (HPGe). The observation of this decay would provide critical insight into our understanding of neutrinos, yielding definitive evidence that neutrinos are Majorana particles and providing information on the absolute mass of neutrinos. Achieving sensitivities to 0{nu}{beta}{beta} decay half-lives on the order of 10{sup 26} years requires ultra-low backgrounds in the 2039 keV region where a 0{nu}{beta}{beta} decay peak would be observed. The goal of our R&D program has been to demonstrate the feasibility of all components of Majorana and to provide an integrated evaluation framework, allowing for optimization of these components in terms of background, background suppression, and signal detection efficiency and acceptance. This report covers work carried out by Majorana collaboration members at the University of Washington as part of the overall Majorana collaboration activities. Specifically the Majorana group at the University of Washington was involved in moving forward on demonstrating technology for clean large-scale cryostats and mounting the HPGe crystals in low-mass holders. The UW activities included assistance in the procurement and assembly of an electroforming system for large size cryostats, and design and fabrication of prototype crystal mounting hardware.
Majorana neutrino masses and the neutrinoless double-beta decay
Faessler, A. [University of Tuebingen, Institute of Theoretical Physics (Germany)], E-mail: amand.faessler@uni-tuebingen.de
2006-12-15
Neutrinoless double-beta decay is forbidden in the Standard Model of electroweak and strong interaction but allowed in most Grand Unified Theories (GUTs). Only if the neutrino is a Majorana particle (identical with its antiparticle) and if it has a mass is neutrinoless double-beta decay allowed. Apart from one claim that the neutrinoless double-beta decay in {sup 76}Ge is measured, one has only upper limits for this transition probability. But even the upper limits allow one to give upper limits for the electron Majorana neutrino mass and upper limits for parameters of GUTs and the minimal R-parity-violating supersymmetric model. One further can give lower limits for the vector boson mediating mainly the right-handed weak interaction and the heavy mainly right-handed Majorana neutrino in left-right symmetric GUTs. For that, one has to assume that the specific mechanism is the leading one for neutrinoless double-beta decay and one has to be able to calculate reliably the corresponding nuclear matrix elements. In the present work, one discusses the accuracy of the present status of calculating of the nuclear matrix elements and the corresponding limits of GUTs and supersymmetric parameters.
Neutrinoless Double Beta Decay and {nu}-Mass Determination
Pedretti, M. [Universita dell Insubria, Via Vallegio 11, 22100 Como (Italy)
2005-10-12
The search for Neutrinoless Double Beta Decay could improve our knowledge on neutrino properties. After a brief discussion on the implications of the observation of this rare process, I will introduce the experimental approaches and review the prospects of the search for this nuclear transition.
New Advances in Neutrinoless Double Beta Decay Matrix Elements
Munoz, Jose Barea [Instituto de Estructura de la Materia, C.S.I.C. Unidad Asociada al Departamento de Fisica Atomica, Molecular y Nuclear, Facultad de Fisica, Universidad de Sevilla, Apartado 1065, 41080 Sevilla (Spain)
2010-08-04
We present the matrix elements necessary to evaluate the half-life of some neutrinoless double beta decay candidates in the framework of the microscopic interacting boson model (IBM). We compare our results with those from other models and extract some simple features of the calculations.
Neutrinoless double beta decay in the microscopic interacting boson model
Iachello, F. [Center for Theoretical Physics, Sloane Physics Laboratory Yale University New Haven, CT 06520-8120 (United States)
2009-11-09
The results of a calculation of the nuclear matrix elements for neutrinoless double beta decay in the closure approximation in several nuclei within the framework of the microscopic interacting boson model (IBM-2) are presented and compared with those calculated in the shell model (SM) and quasiparticle random phase approximation (QRPA)
Conditions for detecting CP violation via neutrinoless double beta decay
Joniec, A.; Zralek, M. [Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland)
2006-02-01
Neutrinoless double beta decay data, together with information on the absolute neutrino masses obtained from the future KATRIN experiment and/or astrophysical measurements, provide a chance to find CP violation in the lepton sector with Majorana neutrinos. We derive and discuss necessary conditions which make discovery of such CP violation possible for the future neutrino oscillation and mass measurements data.
Computer code for double beta decay QRPA based calculations
Barbero, C. A.; Mariano, A.; Krmpoti?, F.; Samana, A. R.; Ferreira, V. dos Santos; Bertulani, C. A.
2014-11-11
The computer code developed by our group some years ago for the evaluation of nuclear matrix elements, within the QRPA and PQRPA nuclear structure models, involved in neutrino-nucleus reactions, muon capture and ?{sup } processes, is extended to include also the nuclear double beta decay.
One-nucleon-induced nonmesonic hypernuclear decay in laboratory coordinates
Galeao, A. P.; Barbero, C.; De Conti, C.; Krmpotic, F.
2013-05-06
We present a formalism for the computation of one-nucleon-induced nonmesonic weak hypernuclear decay rates in laboratory coordinates, within an independent-particle shell model framework, with a view to its generalization to the case of two-nucleon-induced transitions.
Dual-range linearized transimpedance amplifier system
Wessendorf, Kurt O.
2010-11-02
A transimpedance amplifier system is disclosed which simultaneously generates a low-gain output signal and a high-gain output signal from an input current signal using a single transimpedance amplifier having two different feedback loops with different amplification factors to generate two different output voltage signals. One of the feedback loops includes a resistor, and the other feedback loop includes another resistor in series with one or more diodes. The transimpedance amplifier system includes a signal linearizer to linearize one or both of the low- and high-gain output signals by scaling and adding the two output voltage signals from the transimpedance amplifier. The signal linearizer can be formed either as an analog device using one or two summing amplifiers, or alternately can be formed as a digital device using two analog-to-digital converters and a digital signal processor (e.g. a microprocessor or a computer).
Linear transformer driver for pulse generation
Kim, Alexander A; Mazarakis, Michael G; Sinebryukhov, Vadim A; Volkov, Sergey N; Kondratiev, Sergey S; Alexeenko, Vitaly M; Bayol, Frederic; Demol, Gauthier; Stygar, William A
2015-04-07
A linear transformer driver includes at least one ferrite ring positioned to accept a load. The linear transformer driver also includes a first power delivery module that includes a first charge storage devices and a first switch. The first power delivery module sends a first energy in the form of a first pulse to the load. The linear transformer driver also includes a second power delivery module including a second charge storage device and a second switch. The second power delivery module sends a second energy in the form of a second pulse to the load. The second pulse has a frequency that is approximately three times the frequency of the first pulse. The at least one ferrite ring is positioned to force the first pulse and the second pulse to the load by temporarily isolating the first pulse and the second pulse from an electrical ground.
Study of B Meson Decays to ppbarh Final States
Hryn'ova, Tetiana B.; /SLAC
2006-03-22
B mesons are unique among well-established non-quarkonium mesons in their ability to decay into baryons. Baryonic B decays offer a wide range of interesting areas of study: they can be used to test our theoretical understanding of rare decay processes involving baryons, search for direct CP violation and study low-energy QCD. This thesis presents measurements of branching fractions and a study of the decay dynamics of the charmless three-body decays of B meson into p{bar p}h final states, where h = {pi}{sup +}, K{sup +}, K{sub S}{sup 0}, K*{sup 0} or K*{sup +}. With a sample of 232 million {Upsilon}(4S) {yields} B{bar B} events collected with the BaBar detector, we report the first observation of the B {yields} p{bar p}K*{sup 0} decay, and provide improved measurements of branching fractions of the other modes. The distribution of the three final-state particles is of particular interest since it provides dynamical information on the possible presence of exotic intermediate states such as the hypothetical pentaquark states {Theta}*{sup ++} and {Theta}{sup +}in the m{sub pK{sup +}} and m{sub pK{sub S}{sup 0}} spectra, respectively, or glueball states (such as the tensor glueball f{sub J}(2220)) in the m{sub p{bar p}} spectrum. No evidence for exotic states is found and upper limits on the branching fractions are set. An enhancement at low p{bar p} mass is observed in all the B {yields} p{bar p}h modes, and its shape is compared between the decay modes and with the shape of the time-like proton form factor. A Dalitz plot asymmetry in B {yields} p{bar p}K{sup +} mode suggests dominance of the penguin amplitude in this decay and disfavors the possibility that the low mass p{bar p} enhancement originates from the presence of a resonance below threshold (such as the recently seen baryonium candidate at 1835 MeV/c{sup 2}). We also identify decays of the type B {yields} X{sub c{bar c}}h {yields} p{bar p}h, where h = K{sup +}, K{sub S}{sup 0}, K*{sup 0} or K*{sup +}, and X
Beta-decay measurements of neutron-deficient cesium isotopes
Parry, R.F.
1983-03-01
Beta decay endpoint energy measurements of the neutron deficient cesium isotopes were done using an energy spectrum shape fitting technique. This was a departure from the typical method of endpoint energy analysis, the Fermi-Kurie plot. A discussion of the shape fitting procedure and its improved features are discussed. These beta endpoint measurements have led to total decay energies (Q/sub EC/) of the neutron deficient /sup 119/ /sup 123/Cs isotopes. The total decay energies of /sup 122m/Cs (Q/sub EC/ = 6.95 +- 0.25 MeV) and /sup 119/Cs (Q/sub EC/ = 6.26 +- 0.29 MeV) were new measurements. The total decay energies of /sup 123/Cs (Q/sub EC/ = 4.05 +- 0.18 MeV), /sup 122g/Cs (Q/sub EC/ = 7.05 +- 0.18 MeV), /sup 121/Cs (Q/sub EC/ = 5.21 +- 0.22 MeV), and /sup 120/Cs (Q/sub EC/ = 7.38 +- 0.23 MeV) were measurements with significantly improved uncertainties as compared to the literature. Further, a combination of the energy levels derived from previous literature gamma-gamma coincident measurements and the experimental beta-coincident gamma decay energies has supported an improved level scheme for /sup 121/Xe and the proposal of three new energy levels in /sup 119/Xe. Comparison of the experimental cesium mass excesses (determined with our Q/sub EC/ values and known xenon mass excesses) with both the literature and theoretical predicted values showed general agreement except for /sup 120/Cs. Possible explanations for this deviation are discussed.
Observation of Doppler broadening in β -delayed proton- γ decay
Schwartz, S. B.; Wrede, C.; Bennett, M. B.; Liddick, S. N.; Pérez-Loureiro, D.; Bowe, A.; Chen, A. A.; Chipps, K. A.; Cooper, N.; Irvine, D.; et al
2015-09-14
Background: The Doppler broadening of gamma-ray peaks is due to nuclear recoil from beta-delayed nucleon emission can be used to measure the energies of the nucleons. This method has never been tested using beta-delayed proton emission or applied to a recoil heavier than A = 10. Purpose: To test and apply this Doppler broadening method using gamma-ray peaks from the P-26(beta p gamma)Al-25 decay sequence. Methods: A fast beam of P-26 was implanted into a planar Ge detector, which was used as a P-26 beta-decay trigger. The SeGA array of high-purity Ge detectors was used to detect gamma rays frommore » the P-26(beta p gamma)Al-25 decay sequence. Results: Radiative Doppler broadening in beta-delayed proton-gamma decay was observed for the first time. Moreover, the Doppler broadening analysis method was verified using the 1613-keV gamma-ray line for which the proton energies were previously known. The 1776-keV gamma ray de-exciting the 2720 keV Al-25 level was observed in P-26(beta p gamma)Al-25 decay for the first time and used to determine that the center-of-mass energy of the proton emission feeding the 2720-keV level is 5.1 +/- 1.0 (stat.) +/- 0.6 (syst.) MeV, corresponding to a Si-26 excitation energy of 13.3 +/- 1.0 (stat.) +/- 0.6 (syst.) MeV for the proton-emitting level. Conclusions: Finally, the Doppler broadening method has been demonstrated to provide practical measurements of the energies for beta-delayed nucleon emissions populating excited states of nuclear recoils at least as heavy as A = 25.« less
Linear Concentrator Solar Power Plant Illustration
This graphic illustrates linear concentrating solar power (CSP) collectors that capture the sun's energy with large mirrors that reflect and focus the sunlight onto a linear receiver tube. The receiver contains a fluid that is heated by the sunlight and then used to create superheated steam that spins a turbine that drives a generator to produce electricity. Alternatively, steam can be generated directly in the solar field, eliminating the need for costly heat exchangers. In a parabolic trough system, the receiver tube is positioned along the focal line of each parabola-shaped reflector.
Linear and angular retroreflecting interferometric alignment target
Maxey, L. Curtis
2001-01-01
The present invention provides a method and apparatus for measuring both the linear displacement and angular displacement of an object using a linear interferometer system and an optical target comprising a lens, a reflective surface and a retroreflector. The lens, reflecting surface and retroreflector are specifically aligned and fixed in optical connection with one another, creating a single optical target which moves as a unit that provides multi-axis displacement information for the object with which it is associated. This displacement information is useful in many applications including machine tool control systems and laser tracker systems, among others.
Beamstrahlung spectra in next generation linear colliders
Barklow, T.; Chen, P. ); Kozanecki, W. )
1992-04-01
For the next generation of linear colliders, the energy loss due to beamstrahlung during the collision of the e{sup +}e{sup {minus}} beams is expected to substantially influence the effective center-of-mass energy distribution of the colliding particles. In this paper, we first derive analytical formulae for the electron and photon energy spectra under multiple beamstrahlung processes, and for the e{sup +}e{sup {minus}} and {gamma}{gamma} differential luminosities. We then apply our formulation to various classes of 500 GeV e{sup +}e{sup {minus}} linear collider designs currently under study.
Quantifying the impact of decay in bed-net efficacy on malaria transmission
Ngonghala, Calistus N.; Del Valle, Sara Y.; Zhao, Ruijun; Mohammed-Awel, Jemal
2014-08-23
Insecticide-treated nets (ITNs) are at the forefront of malaria control programs and even though the percentage of households in sub-Saharan Africa that owned nets increased from 3% in 2000 to 53% in 2012, many children continue to die from malaria. The potential impact of ITNs on reducing malaria transmission is limited due to inconsistent or improper use, as well as physical decay in effectiveness. Most mathematical models for malaria transmission have assumed a fixed effectiveness rate for bed-nets, which can overestimate the impact of nets on malaria control. We develop a model for malaria spread that captures the decrease inmoreITN effectiveness due to physical and chemical decay, as well as human behavior as a function of time. We perform uncertainty and sensitivity analyses to identify and rank parameters that play a critical role in malaria transmission. These analyses show that the basic reproduction number R0, and the infectious human population are most sensitive to bed-net coverage and the biting rate of mosquitoes. Our results show the existence of a backward bifurcation for the case in which ITN efficacy is constant over time, which occurs for some range of parameters and is characterized by high malaria mortality in humans. This result implies that bringing R0 to less than one is not enough for malaria elimination but rather additional efforts will be necessary to control the disease. For the case in which ITN efficacy decays over time, we determine coverage levels required to control malaria for different ITN efficacies and demonstrate that ITNs with longer useful lifespans perform better in malaria control. We conclude that malaria control programs should focus on increasing bed-net coverage, which can be achieved by enhancing malaria education and increasing bed-net distribution in malaria endemic regions.less
Higgs production and decay in models of a warped extra dimension with a bulk Higgs
Archer, Paul R.; Carena, Marcela; Carmona, Adrian; Neubert, Matthias
2015-01-13
Warped extra-dimension models in which the Higgs boson is allowed to propagate in the bulk of a compact AdS5 space are conjectured to be dual to models featuring a partially composite Higgs boson. They offer a framework with which to investigate the implications of changing the scaling dimension of the Higgs operator, which can be used to reduce the constraints from electroweak precision data. In the context of such models, we calculate the cross section for Higgs production in gluon fusion and the H → γγ decay rate and show that they are finite (at one-loop order) as a consequencemore » of gauge invariance. The extended scalar sector comprising the Kaluza-Klein excitations of the Standard Model scalars is constructed in detail. The largest effects are due to virtual KK fermions, whose contributions to the cross section and decay rate introduce a quadratic sensitivity to the maximum allowed value y* of the random complex entries of the 5D anarchic Yukawa matrices. We find an enhancement of the gluon-fusion cross section and a reduction of the H → γγ rate as well as of the tree-level Higgs couplings to fermions and electroweak gauge bosons. As a result, we perform a detailed study of the correlated signal strengths for different production mechanisms and decay channels as functions of y*, the mass scale of Kaluza-Klein resonances and the scaling dimension of the composite Higgs operator.« less
Auger decay mechanism in photon-stimulated desorption of ions from surfaces
Parks, C.C.
1983-11-01
Photon-stimulated desorption (PSD) of positive ions was studied with synchrotron radiation using an angle-integrating time-of-flight mass spectrometer. Ion yields as functions of photon energy near core levels were measured from condensed gases, alkali fluorides, and other alkali and alkaline earth halides. These results are compared to bulk photoabsorption measurements with emphasis on understanding fundamental desorption mechanisms. The applicability of the Auger decay mechanism, in which ion desorption is strictly proportional to surface absorption, is discussed in detail. The Auger decay model is developed in detail to describe Na/sup +/ and F/sup +/ desorption from NaF following Na(1s) excitation. The major decay pathways of the Na(1s) hole leading to desorption are described and equations for the energetics of ion desorption are developed. Ion desorption spectra of H/sup +/, Li/sup +/, and F/sup +/ are compared to bulk photoabsorption near the F(2s) and Li(1s) edges of LiF. A strong photon beam exposure dependence of ion yields from alkali fluorides is revealed, which may indicate the predominance of metal ion desorption from defect sites. The large role of indirect mechanisms in ion desorption condensed N/sub 2/-O/sub 2/ multilayers is demonstrated and discussed. Ion desorption spectra from several alkali halides and alkaline earth halides are compared to bulk photoabsorption spectra. Relative ion yields from BaF/sub 2/ and a series of alkali halides are discussed in terms of desorption mechanisms.
Higgs production and decay in models of a warped extra dimension with a bulk Higgs
Archer, Paul R.; Carena, Marcela; Carmona, Adrian; Neubert, Matthias
2015-01-13
Warped extra-dimension models in which the Higgs boson is allowed to propagate in the bulk of a compact AdS_{5} space are conjectured to be dual to models featuring a partially composite Higgs boson. They offer a framework with which to investigate the implications of changing the scaling dimension of the Higgs operator, which can be used to reduce the constraints from electroweak precision data. In the context of such models, we calculate the cross section for Higgs production in gluon fusion and the H → γγ decay rate and show that they are finite (at one-loop order) as a consequence of gauge invariance. The extended scalar sector comprising the Kaluza-Klein excitations of the Standard Model scalars is constructed in detail. The largest effects are due to virtual KK fermions, whose contributions to the cross section and decay rate introduce a quadratic sensitivity to the maximum allowed value y_{*} of the random complex entries of the 5D anarchic Yukawa matrices. We find an enhancement of the gluon-fusion cross section and a reduction of the H → γγ rate as well as of the tree-level Higgs couplings to fermions and electroweak gauge bosons. As a result, we perform a detailed study of the correlated signal strengths for different production mechanisms and decay channels as functions of y_{*}, the mass scale of Kaluza-Klein resonances and the scaling dimension of the composite Higgs operator.
Quantifying the impact of decay in bed-net efficacy on malaria transmission
Ngonghala, Calistus N.; Del Valle, Sara Y.; Zhao, Ruijun; Mohammed-Awel, Jemal
2014-08-23
Insecticide-treated nets (ITNs) are at the forefront of malaria control programs and even though the percentage of households in sub-Saharan Africa that owned nets increased from 3% in 2000 to 53% in 2012, many children continue to die from malaria. The potential impact of ITNs on reducing malaria transmission is limited due to inconsistent or improper use, as well as physical decay in effectiveness. Most mathematical models for malaria transmission have assumed a fixed effectiveness rate for bed-nets, which can overestimate the impact of nets on malaria control. We develop a model for malaria spread that captures the decrease in ITN effectiveness due to physical and chemical decay, as well as human behavior as a function of time. We perform uncertainty and sensitivity analyses to identify and rank parameters that play a critical role in malaria transmission. These analyses show that the basic reproduction number R_{0}, and the infectious human population are most sensitive to bed-net coverage and the biting rate of mosquitoes. Our results show the existence of a backward bifurcation for the case in which ITN efficacy is constant over time, which occurs for some range of parameters and is characterized by high malaria mortality in humans. This result implies that bringing R_{0} to less than one is not enough for malaria elimination but rather additional efforts will be necessary to control the disease. For the case in which ITN efficacy decays over time, we determine coverage levels required to control malaria for different ITN efficacies and demonstrate that ITNs with longer useful lifespans perform better in malaria control. We conclude that malaria control programs should focus on increasing bed-net coverage, which can be achieved by enhancing malaria education and increasing bed-net distribution in malaria endemic regions.
Makwana, K. D.; Zhdankin, V.; Li, H.; Daughton, W.; Cattaneo, F.
2015-04-10
We performed simulations of decaying magnetohydrodynamic (MHD) turbulence with a fluid and a kinetic code. The initial condition is an ensemble of long-wavelength, counter-propagating, shear-Alfvén waves, which interact and rapidly generate strong MHD turbulence. The total energy is conserved and the rate of turbulent energy decay is very similar in both codes, although the fluid code has numerical dissipation, whereas the kinetic code has kinetic dissipation. The inertial range power spectrum index is similar in both the codes. The fluid code shows a perpendicular wavenumber spectral slope of k-1.3⊥k⊥-1.3. The kinetic code shows a spectral slope of k-1.5⊥k⊥-1.5 for smaller simulation domain, and k-1.3⊥k⊥-1.3 for larger domain. We then estimate that collisionless damping mechanisms in the kinetic code can account for the dissipation of the observed nonlinear energy cascade. Current sheets are geometrically characterized. Their lengths and widths are in good agreement between the two codes. The length scales linearly with the driving scale of the turbulence. In the fluid code, their thickness is determined by the grid resolution as there is no explicit diffusivity. In the kinetic code, their thickness is very close to the skin-depth, irrespective of the grid resolution. Finally, this work shows that kinetic codes can reproduce the MHD inertial range dynamics at large scales, while at the same time capturing important kinetic physics at small scales.
Makwana, K. D.; Zhdankin, V.; Li, H.; Daughton, W.; Cattaneo, F.
2015-04-10
We performed simulations of decaying magnetohydrodynamic (MHD) turbulence with a fluid and a kinetic code. The initial condition is an ensemble of long-wavelength, counter-propagating, shear-Alfvén waves, which interact and rapidly generate strong MHD turbulence. The total energy is conserved and the rate of turbulent energy decay is very similar in both codes, although the fluid code has numerical dissipation, whereas the kinetic code has kinetic dissipation. The inertial range power spectrum index is similar in both the codes. The fluid code shows a perpendicular wavenumber spectral slope of k-1.3⊥k⊥-1.3. The kinetic code shows a spectral slope of k-1.5⊥k⊥-1.5 for smallermore » simulation domain, and k-1.3⊥k⊥-1.3 for larger domain. We then estimate that collisionless damping mechanisms in the kinetic code can account for the dissipation of the observed nonlinear energy cascade. Current sheets are geometrically characterized. Their lengths and widths are in good agreement between the two codes. The length scales linearly with the driving scale of the turbulence. In the fluid code, their thickness is determined by the grid resolution as there is no explicit diffusivity. In the kinetic code, their thickness is very close to the skin-depth, irrespective of the grid resolution. Finally, this work shows that kinetic codes can reproduce the MHD inertial range dynamics at large scales, while at the same time capturing important kinetic physics at small scales.« less
Efficient Algorithms for Estimating the Absorption Spectrum within Linear Response TDDFT
Brabec, Jiri; Lin, Lin; Shao, Meiyue; Govind, Niranjan; Yang, Chao; Saad, Yousef; Ng, Esmond
2015-10-06
We present two iterative algorithms for approximating the absorption spectrum of molecules within linear response of time-dependent density functional theory (TDDFT) framework. These methods do not attempt to compute eigenvalues or eigenvectors of the linear response matrix. They are designed to approximate the absorption spectrum as a function directly. They take advantage of the special structure of the linear response matrix. Neither method requires the linear response matrix to be constructed explicitly. They only require a procedure that performs the multiplication of the linear response matrix with a vector. These methods can also be easily modified to efficiently estimate the density of states (DOS) of the linear response matrix without computing the eigenvalues of this matrix. We show by computational experiments that the methods proposed in this paper can be much more efficient than methods that are based on the exact diagonalization of the linear response matrix. We show that they can also be more efficient than real-time TDDFT simulations. We compare the pros and cons of these methods in terms of their accuracy as well as their computational and storage cost.
Linearity of Climate Response to Increases in Black Carbon Aerosols
Mahajan, Salil; Evans, Katherine J.; Hack, James J.; Truesdale, John
2013-04-19
The impact of absorbing aerosols on global climate are not completely understood. Here, we present results of idealized experiments conducted with the Community Atmosphere Model (CAM4) coupled to a slab ocean model (CAM4-SOM) to simulate the climate response to increases in tropospheric black carbon aerosols (BC) by direct and semi-direct effects. CAM4-SOM was forced with 0, 1x, 2x, 5x and 10x an estimate of the present day concentration of BC while maintaining their estimated present day global spatial and vertical distribution. The top of the atmosphere (TOA) radiative forcing of BC in these experiments is positive (warming) and increases linearly as the BC burden increases. The total semi-direct effect for the 1x experiment is positive but becomes increasingly negative for higher BC concentrations. The global average surface temperature response is found to be a linear function of the TOA radiative forcing. The climate sensitivity to BC from these experiments is estimated to be 0.42 K $ W^{-1} m^{2}$ when the semi-direct effects are accounted for and 0.22 K $ W^{-1} m^{2}$ with only the direct effects considered. Global average precipitation decreases linearly as BC increases, with a precipitation sensitivity to atmospheric absorption of 0.4 $\\%$ $W^{-1}m^{2}$ . The hemispheric asymmetry of BC also causes an increase in southward cross-equatorial heat transport and a resulting northward shift of the inter-tropical convergence zone in the simulations at a rate of 4$^{\\circ}$N $ PW^{-1}$. Global average mid- and high-level clouds decrease, whereas the low-level clouds increase linearly with BC. The increase in marine stratocumulus cloud fraction over the south tropical Atlantic is caused by increased BC-induced diabatic heating of the free troposphere.
Study of the Decays of Charm Mesons With the BaBar Experiment...
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Study of the Decays of Charm Mesons With the BaBar Experiment Citation Details In-Document Search Title: Study of the Decays of Charm Mesons With the BaBar Experiment You are ...
Radiative Penguin Decays at the B Factories (Conference) | SciTech...
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in radiative penguin decays from the B factories Belle and BABAR. Most notably, I will talk about the recent new observations in the decays B yields (rhoomega) gamma, a...
Double Beta Decay in Xenon-136: Measuring the Neutrino-Emitting...
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Double Beta Decay in Xenon-136: Measuring the Neutrino-Emitting Mode and Searching for Majoron-Emitting Modes Citation Details In-Document Search Title: Double Beta Decay in...
A search for pair production of new light bosons decaying into...
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A search for pair production of new light bosons decaying into muons Citation Details In-Document Search Title: A search for pair production of new light bosons decaying into muons...
A Study of $B \\to J/\\psi K^{(*)} 0 X$ decays (Thesis/Dissertation...
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ThesisDissertation: A Study of B to Jpsi K(*) 0 X decays Citation Details In-Document Search Title: A Study of B to Jpsi K(*) 0 X decays You are accessing a ...
Decay of the X ( 3872 ) into χ c J and the operator product...
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Decay of the X ( 3872 ) into c J and the operator product expansion in effective field theory Citation Details In-Document Search Title: Decay of the X ( 3872 ) into c J and ...
Hadronic decays of the X(3872) to {chi}{sub cJ} in effective...
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Hadronic decays of the X(3872) to chisub cJ in effective field theory Citation Details In-Document Search Title: Hadronic decays of the X(3872) to chisub cJ in effective ...
Decay of theX(3872)into?cJand the operator product expansion...
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Decay of theX(3872)intocJand the operator product expansion in effective field theory Citation Details In-Document Search Title: Decay of theX(3872)intocJand the operator...
The effect of hyperfine mixing in electromagnetic and semileptonic decays of doubly heavy baryons
Albertus, C.; Hernandez, E.; Nieves, J.
2011-05-23
We consider the role played by hyperfine mixing in electromagnetic and semileptonic decays of doubly heavy baryons, which give rise to large corrections to the decay widths in both cases. Our results qualitatively agree with other calculations.
B Decay and CP Violation: CKM Angles and Sides at the BABAR and...
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Conference: B Decay and CP Violation: CKM Angles and Sides at the BABAR and BELLE B-Factories Citation Details In-Document Search Title: B Decay and CP Violation: CKM Angles and ...
Decay Heat Removal in GEN IV Gas-Cooled Fast Reactors (Journal...
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Journal Article: Decay Heat Removal in GEN IV Gas-Cooled Fast Reactors Citation Details In-Document Search Title: Decay Heat Removal in GEN IV Gas-Cooled Fast Reactors The safety ...
Search for Neutrinoless Double-Beta Decay in 136Xe with EXO-200...
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Neutrinoless Double-Beta Decay in 136Xe with EXO-200 Citation Details In-Document Search Title: Search for Neutrinoless Double-Beta Decay in 136Xe with EXO-200 Authors: Auger, M. ;...
Search for lepton-flavour-violating decays of the Higgs boson...
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Journal Article: Search for lepton-flavour-violating decays of the Higgs boson Citation Details In-Document Search Title: Search for lepton-flavour-violating decays of the Higgs...
Remarks on decays of hb(2P) (Journal Article) | SciTech Connect
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Remarks on decays of hb(2P) Citation Details In-Document Search Title: Remarks on decays of hb(2P) Authors: Li, Xin ; Voloshin, M. B. Publication Date: 2012-11-06 OSTI Identifier: ...
Z b ( 10610 ) and Z b ( 10650 ) decays to bottomonium plus pion...
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Z b ( 10610 ) and Z b ( 10650 ) decays to bottomonium plus pion Prev Next Title: Z b ( 10610 ) and Z b ( 10650 ) decays to bottomonium plus pion Authors: Li, Xin ; Voloshin, ...
Remarks on decays of hb(2P) (Journal Article) | DOE PAGES
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Remarks on decays of hb(2P) Prev Next Title: Remarks on decays of hb(2P) Authors: Li, Xin ; Voloshin, M. B. Publication Date: 2012-11-06 OSTI Identifier: 1101292 Type: ...
Metastable vacuum decay in center-stabilized Yang-Mills theory...
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Metastable vacuum decay in center-stabilized Yang-Mills theory at large N Prev Next Title: Metastable vacuum decay in center-stabilized Yang-Mills theory at large N Authors: ...
Z b ( 10610 ) and Z b ( 10650 ) decays to bottomonium plus pion...
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Z b ( 10610 ) and Z b ( 10650 ) decays to bottomonium plus pion Citation Details In-Document Search Title: Z b ( 10610 ) and Z b ( 10650 ) decays to bottomonium plus pion Authors: ...
Neutrinos at IceCube from heavy decaying dark matter (Journal...
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Neutrinos at IceCube from heavy decaying dark matter Citation Details In-Document Search Title: Neutrinos at IceCube from heavy decaying dark matter Authors: Feldstein, Brian ; ...
KLU2 Direct Linear Solver Package
Energy Science and Technology Software Center (OSTI)
2012-01-04
KLU2 is a direct sparse solver for solving unsymmetric linear systems. It is related to the existing KLU solver, (in Amesos package and also as a stand-alone package from University of Florida) but provides template support for scalar and ordinal types. It uses a left looking LU factorization method.
Finite Element Interface to Linear Solvers
Energy Science and Technology Software Center (OSTI)
2005-03-18
Sparse systems of linear equations arise in many engineering applications, including finite elements, finite volumes, and others. The solution of linear systems is often the most computationally intensive portion of the application. Depending on the complexity of problems addressed by the application, there may be no single solver capable of solving all of the linear systems that arise. This motivates the desire to switch an application from one solver librwy to another, depending on themore » problem being solved. The interfaces provided by solver libraries differ greatly, making it difficult to switch an application code from one library to another. The amount of library-specific code in an application Can be greatly reduced by having an abstraction layer between solver libraries and the application, putting a common "face" on various solver libraries. One such abstraction layer is the Finite Element Interface to Linear Solvers (EEl), which has seen significant use by finite element applications at Sandia National Laboratories and Lawrence Livermore National Laboratory.« less
Physics Case for the International Linear Collider
Fujii, Keisuke; Grojean, Christophe; Peskin, Michael E.; Barklow, Tim; Gao, Yuanning; Kanemura, Shinya; Kim, Hyungdo; List, Jenny; Nojiri, Mihoko; Perelstein, Maxim; Poeschl, Roman; Reuter, Juergen; Simon, Frank; Tanabe, Tomohiko; Yu, Jaehoon; Wells, James D.; Murayama, Hitoshi; Yamamoto, Hitoshi; /Tohoku U.
2015-06-23
We summarize the physics case for the International Linear Collider (ILC). We review the key motivations for the ILC presented in the literature, updating the projected measurement uncertainties for the ILC experiments in accord with the expected schedule of operation of the accelerator and the results of the most recent simulation studies.
Notes on beam dynamics in linear accelerators
Gluckstern, R.L.
1980-09-01
A collection of notes, on various aspects of beam dynamics in linear accelerators, which were produced by the author during five years (1975 to 1980) of consultation for the LASL Accelerator Technology (AT) Division and Medium-Energy Physics (MP) Division is presented.
A microcomputer-controlled linear heater
Schuck, V.; Rahimi, S. )
1991-10-01
In this note the circuits and principles of operation of a relatively simple and inexpensive linear temperature ramp generator are described. The upper-temperature limit and the heating rate are controlled by an Apple II microcomputer. The temperature versus time is displayed on the screen and may be plotted by an {ital x}-{ital y} plotter.
Ramos, M.I.M.
1996-10-07
The goal of this work was to study the behavior of the angular distribution of the electron form the decay of the W boson in a specific rest-frame of the W, the Collins-Soper frame. This thesis consists of four major divisions, each dealing with closely related themes: (a) Physics Background, (b) Description of the Hardware and General Software Tools, (c) Description of the Analysis and Specific Tools, and (d) Results and Conclusions. Each division is comprised of one or more chapters and each chapter is divided into sections and subsections.
IR OPTICS MEASUREMENT WITH LINEAR COUPLING'S ACTION-ANGLE PARAMETERIZATION.
LUO, Y.; BAI, M.; PILAT, R.; SATOGATA, T.; TRBOJEVIC, D.
2005-05-16
A parameterization of linear coupling in action-angle coordinates is convenient for analytical calculations and interpretation of turn-by-turn (TBT) beam position monitor (BPM) data. We demonstrate how to use this parameterization to extract the twiss and coupling parameters in interaction regions (IRs), using BPMs on each side of the long IR drift region. The example of TBT BPM analysis was acquired at the Relativistic Heavy Ion Collider (RHIC), using an AC dipole to excite a single eigenmode. Besides the full treatment, a fast estimate of beta*, the beta function at the interaction point (IP), is provided, along with the phase advance between these BPMs. We also calculate and measure the waist of the beta function and the local optics.
Quality Assurance Review of ISOTOPE and ORIGEN Decay Masses for PWR Fuel (51 GWd/MTU)
Gastelum, Jason A.
2011-03-28
This memorandum documents the comparison of ISOTOPE decay mass calculations for PWR 51GW fuel with analogous calculations in ORIGEN.
New precision measurements of free neutron beta decay with cold neutrons
Baeßler, Stefan; Bowman, James David; Penttilä, Seppo I.; Počanić, Dinko
2014-10-14
Precision measurements in free neutron beta decay serve to determine the coupling constants of beta decay, and offer several stringent tests of the standard model. This study describes the free neutron beta decay program planned for the Fundamental Physics Beamline at the Spallation Neutron Source at Oak Ridge National Laboratory, and finally puts it into the context of other recent and planned measurements of neutron beta decay observables.
The Search for Neutrinoless Double Beta Decay with ^{130}Te with CUORE-0
Jonathan Loren Ouellet
2015-06-02
This thesis describes the design, operation and results of an experimental search for neutrinoless double beta decay (0$\
Exact linearized Coulomb collision operator in the moment expansion
Ji, Jeong -Young; Held, Eric D.
2006-10-05
In the moment expansion, the Rosenbluth potentials, the linearized Coulomb collision operators, and the moments of the collision operators are analytically calculated for any moment. The explicit calculation of Rosenbluth potentials converts the integro-differential form of the Coulomb collision operator into a differential operator, which enables one to express the collision operator in a simple closed form for any arbitrary mass and temperature ratios. In addition, it is shown that gyrophase averaging the collision operator acting on arbitrary distribution functions is the same as the collision operator acting on the corresponding gyrophase averaged distribution functions. The moments of the collisionmore » operator are linear combinations of the fluid moments with collision coefficients parametrized by mass and temperature ratios. Furthermore, useful forms involving the small mass-ratio approximation are easily found since the collision operators and their moments are expressed in terms of the mass ratio. As an application, the general moment equations are explicitly written and the higher order heat flux equation is derived.« less
Toward portable programming of numerical linear algebra on manycore...
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Toward portable programming of numerical linear algebra on manycore nodes. Citation Details In-Document Search Title: Toward portable programming of numerical linear algebra on ...
International Linear Collider-A Technical Progress Report (Technical...
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Technical Report: International Linear Collider-A Technical Progress Report Citation Details In-Document Search Title: International Linear Collider-A Technical Progress Report The ...
MHK Technologies/Ocean Current Linear Turbine | Open Energy Informatio...
Open Energy Information (Open El) [EERE & EIA]
Current Linear Turbine < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Ocean Current Linear Turbine.jpg Technology Profile Primary...
Updates to the International Linear Collider Damping Rings Baseline...
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Updates to the International Linear Collider Damping Rings Baseline Design Citation Details In-Document Search Title: Updates to the International Linear Collider Damping Rings...
A Linear Theory of Microwave Instability in Electron Storage...
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Journal Article: A Linear Theory of Microwave Instability in Electron Storage Rings Citation Details In-Document Search Title: A Linear Theory of Microwave Instability in Electron...
Neutrino mass, dark energy, and the linear growth factor (Journal...
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dark energy, and the linear growth factor Citation Details In-Document Search Title: Neutrino mass, dark energy, and the linear growth factor We study the degeneracies between ...
Djalali, Chaden; Paolone, Michael; Weygand, Dennis; Wood, Mike H.
2014-09-01
Although the phenomena of r – w interference has been studied at great length in pionic decay channel over the past 50 years, a study of the interference in a purely electromagnetic production and decay channel has never been performed on an elementary proton target until now. The only published photo-production data of the r - w leptonic decay channel was obtained in the early seventies on C and Be. An investigation of the r - w interference on a Hydrogen was recently completed at Jefferson Lab with the CLAS detector. The di-lepton spectra was fit with two inter- fering relativistic Breit-Wigner functions, and the interference phase was extracted. Preliminary results will be compared to the previous experimental studies in nuclei.
Pan Xiaoyin; Slamet, Marlina; Sahni, Viraht
2010-04-15
We extend our prior work on the construction of variational wave functions {psi} that are functionals of functions {chi}:{psi}={psi}[{chi}] rather than simply being functions. In this manner, the space of variations is expanded over those of traditional variational wave functions. In this article we perform the constrained search over the functions {chi} chosen such that the functional {psi}[{chi}] satisfies simultaneously the constraints of normalization and the exact expectation value of an arbitrary single- or two-particle Hermitian operator, while also leading to a rigorous upper bound to the energy. As such the wave function functional is accurate not only in the region of space in which the principal contributions to the energy arise but also in the other region of the space represented by the Hermitian operator. To demonstrate the efficacy of these ideas, we apply such a constrained search to the ground state of the negative ion of atomic hydrogen H{sup -}, the helium atom He, and its positive ions Li{sup +} and Be{sup 2+}. The operators W whose expectations are obtained exactly are the sum of the single-particle operators W={Sigma}{sub i}r{sub i}{sup n},n=-2,-1,1,2, W={Sigma}{sub i{delta}}(r{sub i}), W=-(1/2){Sigma}{sub i{nabla}i}{sup 2}, and the two-particle operators W={Sigma}{sub n}u{sup n},n=-2,-1,1,2, where u=|r{sub i}-r{sub j}|. Comparisons with the method of Lagrangian multipliers and of other constructions of wave-function functionals are made. Finally, we present further insights into the construction of wave-function functionals by studying a previously proposed construction of functionals {psi}[{chi}] that lead to the exact expectation of arbitrary Hermitian operators. We discover that analogous to the solutions of the Schroedinger equation, there exist {psi}[{chi}] that are unphysical in that they lead to singular values for the expectations. We also explain the origin of the singularity.
New techniques and results in sup 76 Ge double-beta decay
Miley, H.S.; Brodzinski, R.L.; Hensley, W.K.; Reeves, J.H. ); Avignone, F.T. . Dept. of Physics)
1991-09-01
Several methods of lowering the background in germanium double-beta decay experiments are discusses. A technique for increasing confidence in double-beta decay measurements by variation of detector enrichment is demonstrated in the case of two-neutrino decay mode of {sup 76}Ge. The impact of cosmic ray spallation in low-background isotopically enriched germanium detectors is examined.
New techniques and results in {sup 76}Ge double-beta decay
Miley, H.S.; Brodzinski, R.L.; Hensley, W.K.; Reeves, J.H.; Avignone, F.T.
1991-09-01
Several methods of lowering the background in germanium double-beta decay experiments are discusses. A technique for increasing confidence in double-beta decay measurements by variation of detector enrichment is demonstrated in the case of two-neutrino decay mode of {sup 76}Ge. The impact of cosmic ray spallation in low-background isotopically enriched germanium detectors is examined.
Parametric Hazard Function Estimation.
Energy Science and Technology Software Center (OSTI)
1999-09-13
Version 00 Phaze performs statistical inference calculations on a hazard function (also called a failure rate or intensity function) based on reported failure times of components that are repaired and restored to service. Three parametric models are allowed: the exponential, linear, and Weibull hazard models. The inference includes estimation (maximum likelihood estimators and confidence regions) of the parameters and of the hazard function itself, testing of hypotheses such as increasing failure rate, and checking ofmore » the model assumptions.« less
Measurement of indirect CP-violating asymmetries in D0→K+K- and D0→π+π- decays at CDF
Aaltonen, Timo Antero
2014-12-30
We report a measurement of the indirect CP-violating asymmetries (AΓ) between effective lifetimes of anticharm and charm mesons reconstructed in D0→K+K- and D0→π+π- decays. We use the full data set of proton-antiproton collisions collected by the Collider Detector at Fermilab experiment and corresponding to 9.7 fb-1 of integrated luminosity. The strong-interaction decay D*+→D0π+ is used to identify the meson at production as D0 or D¯0. We statistically subtract D0 and D¯0 mesons originating from b-hadron decays and measure the yield asymmetry between anticharm and charm decays as a function of decay time. We measure AΓ(K+K-)=(-0.19±0.15(stat)±0.04(syst))%and AΓ(π+π-)=(-0.01±0.18(stat)±0.03(syst))%. The results are consistentmore » with the hypothesis of CP symmetry and their combination yields AΓ=(-0.12±0.12)%.« less
Jentschura, U. D.; Milstein, A. I.; Terekhov, I. S.; Boie, H.; Scheit, H.; Schwalm, D.
2008-01-15
We present a quasiclassical theory of {alpha} decay accompanied by bremsstrahlung with a special emphasis on the case of {sup 210}Po, with the aim of finding a unified description that incorporates both the radiation during the tunneling through the Coulomb wall and the finite energy E{sub {gamma}} of the radiated photon up to E{sub {gamma}}{approx}Q{sub {alpha}}/{radical}({eta}), where Q{sub {alpha}} is the {alpha}-decay Q-value and {eta} is the Sommerfeld parameter. The corrections with respect to previous quasiclassical investigations are found to be substantial, and excellent agreement with a full quantum mechanical treatment is achieved. Furthermore, we find that a dipole-quadrupole interference significantly changes the {alpha}-{gamma} angular correlation. We obtain good agreement between our theoretical predictions and experimental results.
Particle decay studies at or near closed shells
Toth, K.S.
1985-01-01
We summarize briefly two sets of investigations. In the first one ..cap alpha..-decay rates of neutron-deficient even-even Pb isotopes were studied by using the UNISOR separator on-line at the Holifield Heavy Ion Research Facility. These data indicate that midway between N = 82 and N = 126, the Z = 82 shell gap may not exist. The second investigation, carried out at the Lawrence Berkeley Laboratory 88-Inch Cyclotron and SuperHILAC, has dealt with the delayed-proton decays of the N = 81 precursors /sup 147/Dy, /sup 149/Er, and /sup 151/Yb. All three proton spectra have sharp peaks and thus provide evidence for greatly reduced level densities in the N = 82 proton emitting nuclei /sup 147/Tb, /sup 149/Ho, and /sup 151/Tm. 6 refs., 3 figs.
The MAJORANA DEMONSTRATOR Neutrinoless Double-Beta Decay Experiment
Abgrall, N.; Aguayo, Estanislao; Avignone, III, F. T.; Barabash, A.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Caldwell, A. S.; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Combs, Dustin C.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S. R.; Esterline, James H.; Fast, James E.; Finnerty, P.; Fraenkle, Florian; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M.; Gruszko, J.; Guiseppe, Vincente; Gusev, K.; Hallin, A. L.; Hazama, R.; Hegai, A.; Henning, Reyco; Hoppe, Eric W.; Howard, Stanley; Howe, M. A.; Keeter, K.; Kidd, M. F.; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; Laferriere, Brian D.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; Luke, P.; MacMullin, S.; Martin, R. D.; Mertens, S.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; O'Shaughnessy, Mark D.; Overman, Nicole R.; Phillips, David; Poon, Alan; Pushkin, K.; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shanks, B.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Snyder, N.; Steele, David; Strain, J.; Suriano, Anne-Marie; Thompson, J.; Timkin, V.; Tornow, Werner; Varner, R. L.; Vasilyev, Sergey; Vetter, Kai; Vorren, Kris R.; White, Brandon R.; Wilkerson, J. F.; Williams, T.; Xu, W.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir
2014-01-01
The Majorana Demonstrator will search for the neutrinoless double-beta (ββ (0ν)) decay of the isotope ^{76}Ge with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate that the neutrino is its own antiparticle, demonstrate that lepton number is not conserved, and provide information on the absolute mass scale of the neutrino. TheDemonstrator is being assembled at the 4850-foot level of the SanfordUnderground Research Facility in Lead, SouthDakota. The array will be situated in a low-background environment and surrounded by passive and active shielding. Here we describe the science goals of the Demonstrator and the details of its design.
The MAJORANA DEMONSTRATOR Neutrinoless Double-Beta Decay Experiment
Abgrall, N.; Aguayo, Estanislao; Avignone, Frank T.; Barabash, Alexander S.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Caldwell, A. S.; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Combs, Dustin C.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S. R.; Esterline, James H.; Fast, James E.; Finnerty, P.; Fraenkle, Florian; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M.; Gruszko, J.; Guiseppe, Vincente; Gusev, K.; Hallin, A. L.; Hazama, R.; Hegai, A.; Henning, Reyco; Hoppe, Eric W.; Howard, Stanley; Howe, M. A.; Keeter, K.; Kidd, M. F.; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; Laferriere, Brian D.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; Luke, P.; MacMullin, S.; Martin, R. D.; Mertens, S.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; O'Shaughnessy, C.; Overman, Nicole R.; Phillips, David; Poon, Alan; Pushkin, K.; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shanks, B.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Snyder, N.; Steele, David; Strain, J.; Suriano, Anne-Marie; Thompson, J.; Timkin, V.; Tornow, Werner; Varner, R. L.; Vasilyev, Sergey; Vetter, Kai; Vorren, Kris R.; White, Brandon R.; Wilkerson, J. F.; Williams, T.; Xu, W.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir
2014-06-01
The MAJORANA DEMONSTRATOR will search for the neutrinoless double-beta (ββ(0ν)) decay of the isotope ^{76}Ge with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate that the neutrino is its own antiparticle, demonstrate that lepton number is not conserved, and provide information on the absolute mass scale of the neutrino. The DEMONSTRATOR is being assembled at the 4850-foot level of the Sanford Underground Research Facility in Lead, South Dakota. The array will be situated in a low-background environment and surrounded by passive and active shielding. Here we describe the science goals of the DEMONSTRATOR and the details of its design.
Non-adiabatic perturbations in decaying vacuum cosmology
Zimdahl, W.; Fabris, J.C.; Borges, H.A.; Carneiro, S.; Hiplito-Ricaldi, W.S. E-mail: humberto@ufba.br E-mail: fabris@pq.cnpq.br
2011-04-01
We investigate a spatially flat Friedmann-Lematre-Robertson-Walker cosmology in which a decaying vacuum term causes matter production at late times. Assuming a decay proportional to the Hubble rate, the ratio of the background energy densities of dark matter and dark energy changes with the cosmic scale factor as a{sup ?3/2}. The intrinsically non-adiabatic two-component perturbation dynamics of this model is reduced to a single second-order equation. Perturbations of the vacuum term are shown to be negligible on scales that are relevant for structure formation. On larger scales, dark-energy perturbations give a somewhat higher contribution but remain always smaller than the dark-matter perturbations.
Exclusive B Decays into Final States with Two Charmed Baryons
Chai, Xuedong; /Iowa U.
2010-01-11
This Thesis presents measurements of the decays B{sup -} {yields} {Xi}{sub c}{sup 0}{bar {Lambda}}{sub c}{sup -}, {bar B}{sup 0} {yields} {Xi}{sub c}{sup +}{bar {Lambda}}{sub c}{sup -}, B{sup -} {yields} {Lambda}{sub c}{sup +}{bar {Lambda}}{sub c}{sup -} K{sup -}, and {bar B}{sup 0} {yields} {Lambda}{sub c}{sup +}{bar {Lambda}}{sub c}{sup -} K{sub s}{sup 0} based on 228 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory.
Searches for massive neutrinos in nuclear beta decay
Jaros, J.A.
1992-10-01
The status of searches for massive neutrinos in nuclear beta decay is reviewed. The claim by an ITEP group that the electron antineutrino mass > 17eV has been disputed by all the subsequent experiments. Current measurements of the tritium beta spectrum limit m{sub {bar {nu}}e} < 10 eV. The status of the 17 keV neutrino is reviewed. The strong null results from INS Tokyo and Argonne, and deficiencies in the experiments which reported positive effects, make it unreasonable to ascribe the spectral distortions seen by Simpson, Hime, and others to a 17keV neutrino. Several new ideas on how to search for massive neutrinos in nuclear beta decay are discussed.
The MAJORANA DEMONSTRATOR Neutrinoless Double-Beta Decay Experiment
Abgrall, N.; Aguayo, E.; Avignone, F. T.; Barabash, A. S.; Bertrand, F. E.; Boswell, M.; Brudanin, V.; Busch, M.; Caldwell, A. S.; Chan, Y. -D.; et al
2014-01-01
Tmore » he M ajorana D emonstrator will search for the neutrinoless double-beta ( β β 0 ν ) decay of the isotope Ge with a mixed array of enriched and natural germanium detectors.he observation of this rare decay would indicate that the neutrino is its own antiparticle, demonstrate that lepton number is not conserved, and provide information on the absolute mass scale of the neutrino.he D emonstrator is being assembled at the 4850-foot level of the Sanford Underground Research Facility in Lead, South Dakota.he array will be situated in a low-background environment and surrounded by passive and active shielding. Here we describe the science goals of the D emonstrator and the details of its design. « less
Search for Charged Lepton Violation in Narrow Upsilon Decays
Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /LBL, Berkeley /UC, Berkeley; Hawkes, C.M.; /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Columbus Supercond., Genova /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison
2011-08-19
Charged lepton flavor violating processes are unobservable in the standard model, but they are predicted to be enhanced in several extensions to the standard model, including supersymmetry and models with leptoquarks or compositeness. We present a search for such processes in a sample of 99 x 10{sup 6} {Upsilon}(2S) decays and 117 x 10{sup 6} {Upsilon}(3S) decays collected with the BABAR detector. We place upper limits on the branching fractions {Beta}({Upsilon}(nS) {yields} e{sup {+-}}{tau}{sup {-+}}) and {Beta}({Upsilon}(nS) {yields} {mu}{sup {+-}}{tau}{sup {-+}}) (n = 2, 3) at the 10{sup -6} level and use these results to place lower limits of order 1 TeV on the mass scale of charged lepton flavor violating effective operators.
Search for the proton decay mode with KamLAND
Asakura, K.; Gando, A.; Gando, Y.; Hachiya, T.; Hayashida, S.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, T.; Ishio, S.; et al
2015-09-23
We present a search for the proton decay modemore » $$p \\rightarrow \\bar{v}K^+$$ based on an exposure of 8.97 kton-years in the KamLAND experiment. The liquid scintillator detector is sensitive to successive signals from $$p \\rightarrow \\bar{v}K^+$$ with unique kinematics, which allow us to achieve a detection efficiency of 44%, higher than previous searches in water Cherenkov detectors. We find no evidence of proton decays for this mode. The expected background, which is dominated by atmospheric neutrinos, is 0:9 ± 0.2 events. The nonbackground-subtracted limit on the partial proton lifetime is τΒ($$p \\rightarrow \\bar{v}K^+$$) > 5.4 x 1032 years at 90% C.L.« less
Search for the proton decay mode with KamLAND
Asakura, K.; Gando, A.; Gando, Y.; Hachiya, T.; Hayashida, S.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, T.; Ishio, S.; Koga, M.; Matsuda, R.; Matsuda, S.; Mitsui, T.; Motoki, D.; Nakamura, K.; Obara, S.; Oki, Y.; Oura, T.; Shimizu, I.; Shirahata, Y.; Shirai, J.; Suzuki, A.; Tachibana, H.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B. D.; Yamauchi, Y.; Yoshida, H.; Kozlov, A.; Takemoto, Y.; Yoshida, S.; Fushimi, K.; Grant, C.; Piepke, A.; Banks, T. I.; Berger, B. E.; Freedman, S. J.; Fujikawa, B. K.; O’Donnell, T.; Learned, J. G.; Maricic, J.; Sakai, M.; Dazeley, S.; Svoboda, R.; Winslow, L. A.; Efremenko, Y.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Detwiler, J. A.; Enomoto, S.; Decowski, M. P.
2015-09-23
We present a search for the proton decay mode $p \\rightarrow \\bar{v}K^+$ based on an exposure of 8.97 kton-years in the KamLAND experiment. The liquid scintillator detector is sensitive to successive signals from $p \\rightarrow \\bar{v}K^+$ with unique kinematics, which allow us to achieve a detection efficiency of 44%, higher than previous searches in water Cherenkov detectors. We find no evidence of proton decays for this mode. The expected background, which is dominated by atmospheric neutrinos, is 0:9 ± 0.2 events. The nonbackground-subtracted limit on the partial proton lifetime is τΒ($p \\rightarrow \\bar{v}K^+$) > 5.4 x 10^{32} years at 90% C.L.
Neutrinoless double {beta}-decay and neutrino mass hierarchies
Bilenky, S. M. [Scuola Internazionale Superiore di Studi Avanzati, I-34014 Trieste (Italy); Faessler, Amand; Gutsche, Thomas; Simkovic, Fedor [Institute fuer Theoretische Physik der Universitaet Tuebingen, D-72076 Tuebingen (Germany)
2005-09-01
In the framework of the seesaw mechanism the normal hierarchy is favorable for the neutrino mass spectrum. For this spectrum we present a detailed calculation of the half-lives of neutrinoless double {beta}-decay for several nuclei of experimental interest. The half-lives are evaluated by considering the most comprehensive nuclear matrix elements, which were obtained within the renormalized quasiparticle random phase approximation by the Bratislava-Caltech-Tuebingen group. The dependence of the half-lives on sin{sup 2}{theta}{sub 13} and the lightest neutrino mass is studied. We present also the results of the calculations of the half-lives of neutrinoless double {beta}-decay in the case of the inverted hierarchy of neutrino masses.
Extra dimensions and neutrinoless double beta decay experiments
Gozdz, Marek; Kaminski, Wieslaw A.; Faessler, Amand [Theoretical Physics Department, Maria Curie-Sklodowska University, Lublin (Poland); Institute fuer Theoretische Physik, Universitaet Tuebingen, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)
2005-05-01
The neutrinoless double beta decay is one of the few phenomena, belonging to the nonstandard physics, which is extensively being sought for in experiments. In the present paper the link between the half-life of the neutrinoless double beta decay and theories with large extra dimensions is explored. The use of the sensitivities of currently planned 0{nu}2{beta} experiments: DAMA, CANDLES, COBRA, DCBA, CAMEO, GENIUS, GEM, MAJORANA, MOON, CUORE, EXO, and XMASS, gives the possibility for a nondirect 'experimental' verification of various extra dimensional scenarios. We discuss also the results of the Heidelberg-Moscow Collaboration. The calculations are based on the Majorana neutrino mass generation mechanism in the Arkani-Hamed-Dimopoulos-Dvali model.
Measurement of the Michel rho parameter in direct muon decay
Piilonen, Leo; Haim, D.; Lee, F. S.; Zhang, Y.; Amann, J. F.; Bolton, R. D.; Cooper, M. D.; Foreman, W.; Harrison, R.; Hart, G.; Hogan, G. E.; Kozlowski, T.; Kroupa, M. A.; Mischke, R. E.; Pillai, C.; Schilling, S.; Whitehouse, D.; Chen, Y.; Dzemidzic, M.; Hungerford, E. V. III
1997-05-20
We report on the status of LAMPF experiment E-1240 to measure the Michel {rho} parameter in direct muon decay. This experiment ran in 1993, and the data are currently being analyzed. The expected precision on the {rho} parameter is {+-}0.0008. This result will provide better constraints on new physics, particularly on the charged vector bosons' mixing angle {zeta} in the manifestly left-right symmetric extension of the Standard Model.
CP Violation in B Meson Decays: Experimental Results
Lanceri, Livio; /Trieste U. /INFN, Trieste
2005-08-30
CP violation is intimately connected with the puzzle of matter-antimatter asymmetry and baryogenesis. In the Standard Model of particle physics, the observed CP violation phenomena are accounted for by the Cabibbo-Kobayashi-Maskawa mechanism involving a phase in the quark mixing matrix. This paper is devoted to a review of the experimental status of CP violation in the decays of B mesons.
Nuclear matrix elements for double-β decay
Engel, Jonathan
2015-07-15
Recent progress in nuclear-structure theory has been dramatic. I describe applications in progress of ab inito calculations to double-beta decay, and discuss the recent and future application of generator-coordinate methods to the same problem. I also discuss the old and vexing problem of the renormalization of the weak nuclear axial-vector coupling constant “in medium” and plans to resolve it.
B meson decays into charmless pseudoscalar scalar mesons
Delepine, D.; Lucio M, J. L.; Ramirez, Carlos A.; Mendoza S, J. A.
2007-06-19
The nonleptonic weak decays of meson B into a scalar and pseudoscalar meson are studied. The scalar mesons under consideration are {sigma} (or f0(600)), f0(980), a0(980) and K{sub 0}{sup *}(1430). We calculate the Branching ratios in the Naive Factorization approximation. Scalars are assumed to be qq-bar bounded sates, but an estimation can be obtained in the case they are four bounded states.
Inclusive. chi. (2 P ) production in. Upsilon. (3 S ) decay
Morrison, R.; Schmidt, D.; Procario, M.; Johnson, D.R.; Lingel, K.; Rankin, P.; Smith, J.G.; Alexander, J.; Artuso, M.; Bebek, C.; Berkelman, K.; Besson, D.; Browder, T.E.; Cassel, D.G.; Cheu, E.; Coffman, D.M.; Drell, P.S.; Ehrlich, R.; Galik, R.S.; Garcia-Sciveres, M.; Geiser, B.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Honscheid, K.; Kandaswamy, J.; Katayama, N.; Kreinick, D.L.; Lewis, J.D.; Ludwig, G.S.; Masui, J.; Mevissen, J.; Mistry, N.B.; Nandi, S.; Ng, C.R.; Nordberg, E.; O'Grady, C.; Patterson, J.R.; Peterson, D.; Pisharody, M.; Riley, D.; Sapper, M.; Selen, M.; Worden, H.; Worris, M.; Avery, P.; Freyberger, A.; Rodriguez, J.; Yelton, J.; Kinoshita, K.; Pipkin, F.; Wilson, R.; Wolinski, J.; Xiao, D.; Sadoff, A.J.; Ammar, R.; Baringer, P.; Coppage, D.; Davis, R.; Haas, P.; Kelly, M.; Kwak, N.; Lam, H.; Ro, S.; Kubota, Y.; Nelson, J.K.; Perticone, D.; Poling, R.; Schrenk, S.; Alam, M.S.; Kim, I.J.; Nemati, B.; Romero, V.; Sun, C.R.; Wang, P.; Zoeller, M.M.; Cr
1991-09-23
Using the CsI calorimeter of the CLEO II detector, the spin triplet {chi}{sub {ital b}}(2{ital P}) states are observed in {Upsilon}(3{ital S}) radiative decays with much higher statistics than seen in previous experiments. The observed mass splittings are not described well by theoretical models, while the relative branching ratios agree with predictions that include relativistic corrections to the radiative transition rates.
Numerical simulations of the decay of primordial magnetic turbulence
Kahniashvili, Tina [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania 15213 (United States); Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, ON P3E 2C (Canada); Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Brandenburg, Axel [Nordita, AlbaNova University Center, Roslagstullsbacken 23, 10691 Stockholm (Sweden); Department of Astronomy, Stockholm University, SE 10691 Stockholm (Sweden); Tevzadze, Alexander G. [Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Faculty of Exact and Natural Sciences, Tbilisi State University, 1 Chavchavadze Avenue Tbilisi, GE-0128 (Georgia); Ratra, Bharat [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States)
2010-06-15
We perform direct numerical simulations of forced and freely decaying 3D magnetohydrodynamic turbulence in order to model magnetic field evolution during cosmological phase transitions in the early Universe. Our approach assumes the existence of a magnetic field generated either by a process during inflation or shortly thereafter, or by bubble collisions during a phase transition. We show that the final configuration of the magnetic field depends on the initial conditions, while the velocity field is nearly independent of initial conditions.
An Enquiry Concerning Charmless Semileptonic Decays of Bottom Mesons
Chaisanguanthum, Kris Somboon; /Harvard U. /SLAC
2008-09-19
The branching fractions for the decays B {yields} P{ell}{nu}{sub {ell}}, where P are the pseudoscalar charmless mesons {pi}{sup {+-}}, {pi}{sup 0}, {eta} and {eta}{prime} and {ell} is an electron or muon, are measured with B{sup 0} and B{sup {+-}} mesons found in the recoil of a second B meson decaying as B {yields} D{ell}{nu}{sub {ell}} or B {yields} D*{ell}{nu}{sub {ell}}. The measurements are based on a data set of 348 fb{sup -1} of e{sup +}e{sup -} collisions at {radical}s = 10.58 GeV recorded with the BABAR detector. Assuming isospin symmetry, measured pionic branching fractions are combined into {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}{sub {ell}}) = (1.54 {+-} 0.17{sub (stat)} {+-} 0.09{sub (syst)}) x 10{sup -4}. First evidence of the B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}} decay is seen; its branching fraction is measured to be {Beta}(B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}}) = (0.64 {+-} 0.20{sub (stat)} {+-} 0.03{sub (syst)}) x 10{sup -4}. It is determined that {Beta}(B{sup +} {yields} {eta}{prime}{ell}{sup +}{nu}{sub {ell}}) < 0.47 x 10{sup -4} to 90% confidence. Partial branching fractions for the pionic decays in ranges of the momentum transfer and various published calculations of the B {yields} {pi} hadronic form factor are used to obtain values of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element V{sub ub} between 3.61 and 4.07 x 10{sup -3}.
W boson cross section and decay properties at the Tevatron
K. Bloom
2002-10-16
The authors present the first measurements of {sigma}(p{bar p} {yields} W {yields} {ell}{nu}) and {sigma}(p{bar p} {yields} Z {yields} {ell}{ell}) at {radical}s = 1.96 TeV, along with new measurements of W angular-decay distributions in p{bar p} collisions at {radical}s = 1.8 TeV.
Non-Linear Seismic Soil Structure Interaction (SSI) Method for Developing Non-Linear Seismic SSI Analysis Techniques Justin Coleman, P.E. October 25th, 2011
Some Comments on the Decays of eta (550)
DOE R&D Accomplishments [OSTI]
Veltman, M.; Yellin, J.
1966-07-01
Various decay modes of the {eta}(500) are discussed. The relations, through SU{sub 3} and the Gell-Mann, Sharp, Wagner model, between the {eta}-decay modes and the modes {eta} {yields} {pi}{pi}{gamma), {pi}{sup 0} {yields} {gamma}{gamma} are investigated taking into account {eta}-{eta}{sup *} mixing. The present experimental values for the neutral branching ratios plus the shape of the {eta} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0} Dalitz plot are shown to require a 25% {vert_bar}{Delta}{rvec I}{vert_bar} = 3 contribution to the {eta} {yields} 3{pi} amplitude. The connection between a possible charge asymmetry in {eta} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0} and the branching ratio {Gamma}{sub {eta} {yields} {pi}{sup 0}e{sup +}e{sup {minus}}}/{Gamma}{sub {eta}}{sup all} is investigated in the framework of a model proposed earlier by several authors. It is shown that there is no conflict between the existing data and this model. The Dalitz plot distribution of {eta} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0} is discussed under various assumptions about the properties of the interaction responsible for the decay. (auth)
Search for Neutrinoless Double Beta Decay with the CUORE experiment
Gorla, P. [Laboratori Nazionali del Gran Sasso-INFN, S.S. 17 bis, km 18-910 67010 Assergi (Italy)
2009-12-17
CUORE is a next generation experiment aimed at the detection of neutrinoless Double Beta Decay of the nuclide {sup 130}Te. The experiment, which will take place in the Gran Sasso National Laboratory (Italy), will look for this rare decay using the macrobolometric technique with a prospected array of 988 detectors. Each bolometer will be constituted by a 5x5x5 cm{sup 3} TeO{sub 2} crystal, for a total mass of about 200 kg of {sup 130}Te, and will be maintained at a temperature of 10 mK. CUORE will probe the effective mass of the neutrino with a sensitivity of a few tens of meV. If an excess of counts are observed above background at the 2.5 MeV corresponding to the Q-value of the decay, CUORE will answer several questions that are still open in the field of neutrino physics, such as the determination of the particle's Majorana nature and of the absolute mass scale. A prototype for CUORE in Gran Sasso, named CUORICINO, has just closed after five years proving its importance as a stand-alone experiment.
Search for T violation in charm meson decays
Link, J.M.; Yager, P.M.; Anjos, J.C.; Bediaga, I.; Castromonte, C.; Machado, A.A.; Magnin, J.; Massafferri, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; dos Reis, A.C.; Carrillo, S.; Casimiro, E.; Cuautle, E.; Sanchez-Hernandez, A.; Uribe, C.; Vazquez, F.; Agostino, L.; Cinquini, L.; Cumalat, J.P.; /Colorado U. /Fermilab /Frascati /Guanajuato U. /Illinois U., Urbana /Indiana U. /Korea U. /Kyungpook Natl. U. /INFN, Milan /Milan U. /North Carolina U. /Pavia U. /INFN, Pavia /Rio de Janeiro, Pont. U. Catol. /Puerto Rico U., Mayaguez /South Carolina U. /Tennessee U. /Vanderbilt U. /Wisconsin U., Madison
2005-06-01
Using data from the FOCUS (E831) experiment, they have searched for T violation in charm meson decays using the four-body decay channels D{sup 0} {yields} K{sup -}K{sup +} {pi}{sup -}{pi}{sup +}, D{sup +} {yields} K{sub S}{sup 0}K{sup +}{pi}{sup -}{pi}{sup +}, and D{sub s}{sup +} {yields} K{sub S}{sup 0}K{sup +}{pi}{sup -}{pi}{sup +}. The T violation asymmetry is obtained using triple-product correlations and assuming the validity of the CPT theorem. They find the asymmetry values to be A{sub T{sub viol}}(D{sup 0}) = 0.010 {+-} 0.057(stat.) {+-} 0.037(syst.), A{sub T{sub viol}}(D{sup +}) = 0.023 {+-} 0.062(stat.) {+-} 0.022(syst.), and A{sub T{sub viol}}(D{sub s}{sup +}) = -0.036 {+-} 0.067(stat.) {+-} 0.023(syst.). Each measurement is consistent with no T violation. New measurements of the CP asymmetries for some of these decay modes are also presented.
Gravitino dark matter from Q-ball decays
Shoemaker, Ian M.; Kusenko, Alexander
2009-10-01
Affleck-Dine baryogenesis, accompanied by the formation and subsequent decay of Q-balls, can generate both the baryon asymmetry of the Universe and dark matter in the form of gravitinos. The gravitinos from Q-ball decay dominate over the thermally produced population if the reheat temperature T{sub R} < or approx. 10{sup 7} GeV. We show that a gravitino with mass {approx}1 GeV is consistent with all observational bounds and can explain the baryon-to-dark-matter ratio in the gauge-mediated models of supersymmetry breaking for a wide range of cosmological and Q-ball parameters. Moreover, decaying Q-balls can be the dominant production mechanism for m{sub 3/2}<1 GeV gravitinos if the Q-balls are formed from a (B-L)=0 condensate, which produces no net baryon asymmetry. Gravitinos with masses in the range 50 eV < or approx. m{sub 3/2} < or approx. 100 keV produced in this way can act as warm dark matter and can have observable imprint on the small-scale structure.
Enhanced dielectric-wall linear accelerator
Sampayan, S.E.; Caporaso, G.J.; Kirbie, H.C.
1998-09-22
A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. 6 figs.
Noise in phase-preserving linear amplifiers
Pandey, Shashank; Jiang, Zhang; Combes, Joshua; Caves, Carlton M.
2014-12-04
The purpose of a phase-preserving linear amplifier is to make a small signal larger, so that it can be perceived by instruments incapable of resolving the original signal, while sacrificing as little as possible in signal-to-noise. Quantum mechanics limits how well this can be done: the noise added by the amplifier, referred to the input, must be at least half a quantum at the operating frequency. This well-known quantum limit only constrains the second moments of the added noise. Here we provide the quantum constraints on the entire distribution of added noise: any phasepreserving linear amplifier is equivalent to a parametric amplifier with a physical state ? for the ancillary mode; ? determines the properties of the added noise.
Tilted panel linear echelon solar collector
Appeldorn, R.H.; Vanderwerf, D.F.
1989-01-31
A solar concentrator is described for directing incident solar radiation to a linear focus, comprising: a planar base surface being positioned at an angle phi, which is greater than 0/sup 0/ but less than 90/sup 0/, with respect to a direction which is normal to the incident solar radiation; a plurality of planar reflective elements set along the planar base surface each of which is positioned at an angle ..cap alpha..' with respect to the planar base surface and which varies for each of the planar reflective elements to reflect the incident solar radiation to the linear focus, the plurality of planar reflective elements being separated from each other by substantially planar riser elements, the riser elements being substantially normal to the planar base surface, each of the planar reflective elements making an angle ..cap alpha.. with respect to the direction which is normal to the incident solar radiation.
Enhanced dielectric-wall linear accelerator
Sampayan, Stephen E.; Caporaso, George J.; Kirbie, Hugh C.
1998-01-01
A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface.
Linear mechanism of surface gravity wave generation in horizontally sheared flow
Kalashnik, M. V.
2008-01-15
An analysis is presented of a linear mechanism of surface gravity wave generation in a horizontally sheared flow in a fluid layer with free boundary. A free-surface flow of this type is found to be algebraically unstable. The development of instability leads to the formation of surface gravity waves whose amplitude grows with time according to a power law. Flow stability is analyzed by using a nonmodal approach in which the behavior of a spatial Fourier harmonic of a disturbance is considered in a semi-Lagrangian frame of reference moving with the flow. Shear-flow disturbances are divided into two classes (wave and vortex disturbances) depending on the value of potential vorticity. It is shown that vortex disturbances decay with time while the energy of wave disturbances increases indefinitely. Transformation of vortex disturbances into wave ones under strong shear is described.
Radio frequency quadrupole resonator for linear accelerator
Moretti, Alfred
1985-01-01
An RFQ resonator for a linear accelerator having a reduced level of interfering modes and producing a quadrupole mode for focusing, bunching and accelerating beams of heavy charged particles, with the construction being characterized by four elongated resonating rods within a cylinder with the rods being alternately shorted and open electrically to the shell at common ends of the rods to provide an LC parallel resonant circuit when activated by a magnetic field transverse to the longitudinal axis.
High gradient accelerators for linear light sources
Barletta, W.A.
1988-09-26
Ultra-high gradient radio frequency linacs powered by relativistic klystrons appear to be able to provide compact sources of radiation at XUV and soft x-ray wavelengths with a duration of 1 picosecond or less. This paper provides a tutorial review of the physics applicable to scaling the present experience of the accelerator community to the regime applicable to compact linear light sources. 22 refs., 11 figs., 21 tabs.
The Next Linear Collider: NLC2001
D. Burke et al.
2002-01-14
Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find this new physics, they must find out what it is. These experiments must also define the next important threshold in energy. The need is to understand physics at the TeV energy scale as well as the physics at the 100-GeV energy scale is now understood. This will require both the LHC and a companion linear electron-positron collider. A first Zeroth-Order Design Report (ZDR) [2] for a second-generation electron-positron linear collider, the Next Linear Collider (NLC), was published five years ago. The NLC design is based on a high-frequency room-temperature rf accelerator. Its goal is exploration of elementary particle physics at the TeV center-of-mass energy, while learning how to design and build colliders at still higher energies. Many advances in accelerator technologies and improvements in the design of the NLC have been made since 1996. This Report is a brief update of the ZDR.
Communications circuit including a linear quadratic estimator
Ferguson, Dennis D.
2015-07-07
A circuit includes a linear quadratic estimator (LQE) configured to receive a plurality of measurements a signal. The LQE is configured to weight the measurements based on their respective uncertainties to produce weighted averages. The circuit further includes a controller coupled to the LQE and configured to selectively adjust at least one data link parameter associated with a communication channel in response to receiving the weighted averages.
Linearity Testing of Photovoltaic Cells (Poster)
Emery, K.; Winter, S.; Pinegar, S.; Nalley, D.
2006-05-01
International PV standards require that the short-circuit current or response of the reference device be linear with total irradiance. Accredited calibration laboratories can not assume that their reference device is linear unless another accredited laboratory has performed the measurement. The NREL PV performance laboratory is ISO 17025 accredited for primary reference cell, secondary reference cell and secondary module calibrations. Limited labor resources necessitated the development of a technique to determine linearity without taking significant labor or technical skill. The two-lamp method is insensitive to the spectrum of the light or spatial nonuniformity changing as the irradiance is varied. It does assume that the temperature does not change with irradiance and that the light-source spectrum resembles the solar spectrum. This requirement is only because nonlinear mechanisms in the photo-current are wavelength dependent. A laser for example may show the same device as linear or very nonlinear with irradiance depending on the wavelength. The two-lamp method assumes that the lamp intensities when individually irradiating the sample are the same as when both lamps irradiate the sample. The presence of room light only limits the lowest irradiance that can be evaluated. Unlike other methods, the two-lamp method does not allow the current to be corrected for nonlinear effects. The most appealing aspect of the two-lamp method when compared with other methods for a high-volume calibration laboratory is that it is fast and does not require operator intervention to change the irradiances and is difficult for the operator to make mistakes that would affect the outcome.
Linearity Testing of Photovoltaic Cells: Preprint
Emery, K.; Winter, S.; Pinegar, S.; Nalley D.
2006-05-01
Photovoltaic devices are rated in terms of their peak power with respect to a specific spectrum, total irradiance, and temperature. To rate photovoltaic devices, a reference detector is required whose response is linear with total irradiance. This paper describes a procedure to determine the linearity of the short-circuit current (Isc) versus the total irradiance (Etot) by illuminating a reference cell with two lamps. A device is linear if the current measured with both lamps illuminating the cell is the same as the sum of the currents with each lamp illuminating the cell. The two-lamp method is insensitive to the light spectra or spatial nonuniformity changing with irradiance. The two-lamp method is rapid, easy to implement, and does not require operator intervention to change the irradiances. The presence of room light only limits the lowest irradiance that can be evaluated. Unlike other methods, the two-lamp method does not allow the current to be corrected for nonlinear effects.
Ye, Tianyu; Liu, Han -Chun; Wang, Zhuo; Wegscheider, W.; Mani, Ramesh G.
2015-10-09
A comparative study of the radiation-induced magnetoresistance oscillations in the high mobility GaAs/AlGaAs heterostructure two dimensional electron system (2DES) under linearly- and circularly- polarized microwave excitation indicates a profound difference in the response observed upon rotating the microwave launcher for the two cases, although circularly polarized microwave radiation induced magnetoresistance oscillations observed at low magnetic fields are similar to the oscillations observed with linearly polarized radiation. For the linearly polarized radiation, the magnetoresistive response is a strong sinusoidal function of the launcher rotation (or linear polarization) angle, θ. As a result, for circularly polarized radiation, the oscillatory magnetoresistive response is hardly sensitive to θ.
Hong Qin and Ronald C. Davidson
2011-07-19
In a linear trap confining a one-component nonneutral plasma, the external focusing force is a linear function of the configuration coordinates and/or the velocity coordinates. Linear traps include the classical Paul trap and the Penning trap, as well as the newly proposed rotating-radio- frequency traps and the Mobius accelerator. This paper describes a class of self-similar nonlinear solutions of nonneutral plasma in general time-dependent linear focusing devices, with self-consistent electrostatic field. This class of nonlinear solutions includes many known solutions as special cases.
Towards a Future Linear Collider and The Linear Collider Studies at CERN
None
2016-07-12
During the week 18-22 October, more than 400 physicists will meet at CERN and in the CICG (International Conference Centre Geneva) to review the global progress towards a future linear collider. The 2010 International Workshop on Linear Colliders will study the physics, detectors and accelerator complex of a linear collider covering both the CLIC and ILC options. Among the topics presented and discussed will be the progress towards the CLIC Conceptual Design Report in 2011, the ILC Technical Design Report in 2012, physics and detector studies linked to these reports, and an increasing numbers of common working group activities. The seminar will give an overview of these topics and also CERNâs linear collider studies, focusing on current activities and initial plans for the period 2011-16. n.b: The Council Chamber is also reserved for this colloquium with a live transmission from the Main Auditorium.
Towards a Future Linear Collider and The Linear Collider Studies at CERN
None
2011-10-06
During the week 18-22 October, more than 400 physicists will meet at CERN and in the CICG (International Conference Centre Geneva) to review the global progress towards a future linear collider. The 2010 International Workshop on Linear Colliders will study the physics, detectors and accelerator complex of a linear collider covering both the CLIC and ILC options. Among the topics presented and discussed will be the progress towards the CLIC Conceptual Design Report in 2011, the ILC Technical Design Report in 2012, physics and detector studies linked to these reports, and an increasing numbers of common working group activities. The seminar will give an overview of these topics and also CERN?s linear collider studies, focusing on current activities and initial plans for the period 2011-16. n.b: The Council Chamber is also reserved for this colloquium with a live transmission from the Main Auditorium.
Khachatryan, Vardan
2016-01-13
Our search for a very light Higgs boson decaying into a pair of t leptons is presented within the framework of the next-to-minimal supersymmetric standard model. This search is based on a data set corresponding to an integrated luminosity of 19.7 fb-1 of proton-proton collisions collected by the CMS experiment at a centre-of-mass energy of 8 TeV. The signal is defined by the production of either of the two lightest scalars, h1 or h2, via gluon-gluon fusion and subsequent decay into a pair of the lightest Higgs bosons, a1 or h1. The h1 or h2 boson is identified with themore » observed state at a mass of 125 GeV. The analysis searches for decays of the a1 (h1) states into pairs of t leptons and covers a mass range for the a1 (h1) boson of 4 to 8 GeV. Furthermore, the search reveals no significant excess in data above standard model background expectations, and an upper limit is set on the signal production cross section times branching fraction as a function of the a1 (h1) boson mass. The 95% confidence level limit ranges from 4.5 pb at ma1 (mh1 ) = 8 GeV to 10.3 pb at ma1 (mh1 ) = 5 GeV.« less
Simple Limits on Achieving A Quasi-Linear Magnetic Compression for an FEL Driver
Sun, Yipeng; /SLAC
2012-02-16
Free electron lasers (FEL) need a very bright electron beam in three dimensions and a high peak charge density. In order to compress an initially longer electron bunch generated from the photoinjector, magnetic bunch compression systems are widely employed. In this paper, first harmonic RF linearization and its associated requirements are reviewed. Meanwhile it is also briefly discussed what is the relation between a proper initial bunch length and main RF frequency, when a harmonic RF linearization is included. Then given a reasonable bunch compression ratio, a proper initial bunch length as a function of the main RF frequency and RF phase is estimated analytically by several approaches, assuming that no harmonic RF section is needed to linearize the energy modulation introduced during main RF acceleration, and at the same time still linearly compress the bunch length. Next the upper limit of the bunch compression ratio in a single stage is evaluated analytically. The analytical relations derived on choosing a proper initial bunch length as a function of main RF frequency are confirmed by numerical simulation. These simple limit provide rough estimations and may be beneficial for choosing bunch compression ratios in different stages of an FEL driver, especially in a first stage bunch compression where there is usually a harmonic RF linearization applied. It may also be useful in evaluating the possibility of low charge operation mode without any harmonic RF linearization, where a shorter initial bunch length can be achieved from the photoinjector.
Charmless three-body decays of B mesons
Cheng, H.-Y.; Chua, C.-K.; Soni, Amarjit
2007-11-01
An exploratory study of charmless 3-body decays of B mesons is presented using a simple model based on the framework of the factorization approach. The nonresonant contributions arising from B{yields}P{sub 1}P{sub 2} transitions are evaluated using heavy meson chiral perturbation theory (HMChPT). The momentum dependence of nonresonant amplitudes is assumed to be in the exponential form e{sup -{alpha}{sub N}{sub R}}{sup p{sub B}{center_dot}}{sup (p{sub i}+p{sub j})} so that the HMChPT results are recovered in the soft meson limit p{sub i},p{sub j}{yields}0. In addition, we have identified another large source of the nonresonant signal in the matrix elements of scalar densities, e.g.
Linear Collider Physics Resource Book Snowmass 2001
Ronan , M.T.
2001-06-01
The American particle physics community can look forward to a well-conceived and vital program of experimentation for the next ten years, using both colliders and fixed target beams to study a wide variety of pressing questions. Beyond 2010, these programs will be reaching the end of their expected lives. The CERN LHC will provide an experimental program of the first importance. But beyond the LHC, the American community needs a coherent plan. The Snowmass 2001 Workshop and the deliberations of the HEPAP subpanel offer a rare opportunity to engage the full community in planning our future for the next decade or more. A major accelerator project requires a decade from the beginning of an engineering design to the receipt of the first data. So it is now time to decide whether to begin a new accelerator project that will operate in the years soon after 2010. We believe that the world high-energy physics community needs such a project. With the great promise of discovery in physics at the next energy scale, and with the opportunity for the uncovering of profound insights, we cannot allow our field to contract to a single experimental program at a single laboratory in the world. We believe that an e{sup +}e{sup -} linear collider is an excellent choice for the next major project in high-energy physics. Applying experimental techniques very different from those used at hadron colliders, an e{sup +}e{sup -} linear collider will allow us to build on the discoveries made at the Tevatron and the LHC, and to add a level of precision and clarity that will be necessary to understand the physics of the next energy scale. It is not necessary to anticipate specific results from the hadron collider programs to argue for constructing an e{sup +}e{sup -} linear collider; in any scenario that is now discussed, physics will benefit from the new information that e{sup +}e{sup -} experiments can provide. This last point merits further emphasis. If a new accelerator could be designed and
Kohler, Annegret; Kuo, Alan; Nagy, Laszlo G.; Morin, Emmanuelle; Barry, Kerrie W.; Buscot, Francois; Canbäck, Björn; Choi, Cindy; Cichocki, Nicolas; Clum, Alicia; Colpaert, Jan; Copeland, Alex; Costa, Mauricio D.; Doré, Jeanne; Floudas, Dimitrios; Gay, Gilles; Girlanda, Mariangela; Henrissat, Bernard; Herrmann, Sylvie; Hess, Jaqueline; Högberg, Nils; Johansson, Tomas; Khouja, Hassine-Radhouane; LaButti, Kurt; Lahrmann, Urs; Levasseur, Anthony; Lindquist, Erika A.; Lipzen, Anna; Marmeisse, Roland; Martino, Elena; Murat, Claude; Ngan, Chew Y.; Nehls, Uwe; Plett, Jonathan M.; Pringle, Anne; Ohm, Robin A.; Perotto, Silvia; Peter, Martina; Riley, Robert; Rineau, Francois; Ruytinx, Joske; Salamov, Asaf; Shah, Firoz; Sun, Hui; Tarkka, Mika; Tritt, Andrew; Veneault-Fourrey, Claire; Zuccaro, Alga; Tunlid, Anders; Grigoriev, Igor V.; Hibbett, David S.; Martin, Francis
2015-02-23
To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergent evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.
Kohler, Annegret; Kuo, Alan; Nagy, Laszlo G.; Morin, Emmanuelle; Barry, Kerrie W.; Buscot, Francois; Canbäck, Björn; Choi, Cindy; Cichocki, Nicolas; Clum, Alicia; et al
2015-02-23
To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergentmore » evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.« less
Chatrchyan, Serguei
2014-08-01
A search for invisible decays of Higgs bosons is performed using the vector boson fusion and associated ZH production modes. In the ZH mode, the Z boson is required to decay to a pair of charged leptons or a b b-bar quark pair. The searches use the 8 TeV pp collision dataset collected by the CMS detector at the LHC, corresponding to an integrated luminosity of up to 19.7 inverse femtobarns. Certain channels include data from 7 TeV collisions corresponding to an integrated luminosity of 4.9 inverse femtobarns. The searches are sensitive to non-standard-model invisible decays of the recently observedmore » Higgs boson, as well as additional Higgs bosons with similar production modes and large invisible branching fractions. In all channels, the observed data are consistent with the expected standard model backgrounds. Limits are set on the production cross section times invisible branching fraction, as a function of the Higgs boson mass, for the vector boson fusion and ZH production modes. By combining all channels, and assuming standard model Higgs boson cross sections and acceptances, the observed (expected) upper limit on the invisible branching fraction at m[H] = 125 GeV is found to be 0.58 (0.44) at 95% confidence level. We interpret this limit in terms of a Higgs-portal model of dark matter interactions.« less
A search for long-lived particles that stop in the CMS detector and decay to muons
Alimena, Juliette
2016-01-01
A search for long-lived particles that are produced in proton-proton collisions at the CERN LHC, come to rest in the CMS detector, and decay to muons is presented. The decays of the stopped particles could be observed during the intervals between LHC beam crossings, at times that are well separated from any proton-proton collisions. The analysis uses 19.7 1/fb of 8 TeV data collected by CMS in 2012, during a search interval of 293 hours of trigger livetime. Massive, long-lived particles do not exist in the Standard Model, and so any sign of them would be an indication of new physics. The results are interpreted with a model that predicts a long-lived particle that has a charge of twice the electron charge and that behaves like a lepton. Cross section limits are set for each long-lived particle mass as a function of lifetime, for lifetimes between 100 ns and 10 days. These are the first limits for long-lived stopped particles that decay to muons.
The decay of hot nuclei formed in La-induced reactions at E/A=45 MeV
Libby, B.
1993-01-01
The decay of hot nuclei formed in the reactions [sup 139]La + [sup 27]Al, [sup 51]V, [sup nat]Cu, and [sup 139]La were studied by the coincident detection of up to four complex fragments (Z > 3) emitted in these reactions. Fragments were characterized as to their atomic number, energy and in- and out-of-plane angles. The probability of the decay by an event of a given complex fragment multiplicity as a function of excitation energy per nucleon of the source is nearly independent of the system studied. Additionally, there is no large increase in the proportion of multiple fragment events as the excitation energy of the source increases past 5 MeV/nucleon. This is at odds with many prompt multifragmentation models of nuclear decay. The reactions [sup 139]La + [sup 27]Al, [sup 51]V, [sup nat]Cu were also studied by combining a dynamical model calculation that simulates the early stages of nuclear reactions with a statistical model calculation for the latter stages of the reactions. For the reaction [sup 139]La + [sup 27]Al, these calculations reproduced many of the experimental features, but other features were not reproduced. For the reaction [sup 139]La + [sup 51]V, the calculation failed to reproduce somewhat more of the experimental features. The calculation failed to reproduce any of the experimental features of the reaction [sup 139]La + [sup nat]Cu, with the exception of the source velocity distributions.
The decay of hot nuclei formed in La-induced reactions at E/A=45 MeV
Libby, B.
1993-05-01
The decay of hot nuclei formed in the reactions {sup 139}La + {sup 27}Al, {sup 51}V, {sup nat}Cu, and {sup 139}La were studied by the coincident detection of up to four complex fragments (Z > 3) emitted in these reactions. Fragments were characterized as to their atomic number, energy and in- and out-of-plane angles. The probability of the decay by an event of a given complex fragment multiplicity as a function of excitation energy per nucleon of the source is nearly independent of the system studied. Additionally, there is no large increase in the proportion of multiple fragment events as the excitation energy of the source increases past 5 MeV/nucleon. This is at odds with many prompt multifragmentation models of nuclear decay. The reactions {sup 139}La + {sup 27}Al, {sup 51}V, {sup nat}Cu were also studied by combining a dynamical model calculation that simulates the early stages of nuclear reactions with a statistical model calculation for the latter stages of the reactions. For the reaction {sup 139}La + {sup 27}Al, these calculations reproduced many of the experimental features, but other features were not reproduced. For the reaction {sup 139}La + {sup 51}V, the calculation failed to reproduce somewhat more of the experimental features. The calculation failed to reproduce any of the experimental features of the reaction {sup 139}La + {sup nat}Cu, with the exception of the source velocity distributions.
Chatrchyan, Serguei
2014-08-01
A search for invisible decays of Higgs bosons is performed using the vector boson fusion and associated ZH production modes. In the ZH mode, the Z boson is required to decay to a pair of charged leptons or a b b-bar quark pair. The searches use the 8 TeV pp collision dataset collected by the CMS detector at the LHC, corresponding to an integrated luminosity of up to 19.7 inverse femtobarns. Certain channels include data from 7 TeV collisions corresponding to an integrated luminosity of 4.9 inverse femtobarns. The searches are sensitive to non-standard-model invisible decays of the recently observed Higgs boson, as well as additional Higgs bosons with similar production modes and large invisible branching fractions. In all channels, the observed data are consistent with the expected standard model backgrounds. Limits are set on the production cross section times invisible branching fraction, as a function of the Higgs boson mass, for the vector boson fusion and ZH production modes. By combining all channels, and assuming standard model Higgs boson cross sections and acceptances, the observed (expected) upper limit on the invisible branching fraction at m[H] = 125 GeV is found to be 0.58 (0.44) at 95% confidence level. We interpret this limit in terms of a Higgs-portal model of dark matter interactions.
Noiseless Vlasov–Poisson simulations with linearly transformed particles
Campos Pinto, Martin; Sonnendrücker, Eric; Friedman, Alex; Grote, David P.; Lund, Steve M.
2014-10-15
We introduce a deterministic discrete-particle simulation approach, the Linearly-Transformed Particle-In-Cell (LTPIC) method, that employs linear deformations of the particles to reduce the noise traditionally associated with particle schemes. Formally, transforming the particles is justified by local first order expansions of the characteristic flow in phase space. In practice the method amounts of using deformation matrices within the particle shape functions; these matrices are updated via local evaluations of the forward numerical flow. Because it is necessary to periodically remap the particles on a regular grid to avoid excessively deforming their shapes, the method can be seen as a development of Denavit's Forward Semi-Lagrangian (FSL) scheme (Denavit, 1972 [8]). However, it has recently been established (Campos Pinto, 2012 [20]) that the underlying Linearly-Transformed Particle scheme converges for abstract transport problems, with no need to remap the particles; deforming the particles can thus be seen as a way to significantly lower the remapping frequency needed in the FSL schemes, and hence the associated numerical diffusion. To couple the method with electrostatic field solvers, two specific charge deposition schemes are examined, and their performance compared with that of the standard deposition method. Finally, numerical 1d1v simulations involving benchmark test cases and halo formation in an initially mismatched thermal sheet beam demonstrate some advantages of our LTPIC scheme over the classical PIC and FSL methods. Benchmarked test cases also indicate that, for numerical choices involving similar computational effort, the LTPIC method is capable of accuracy comparable to or exceeding that of state-of-the-art, high-resolution Vlasov schemes.
Practical application of equivalent linearization approaches to nonlinear piping systems
Park, Y.J.; Hofmayer, C.H.
1995-05-01
The use of mechanical energy absorbers as an alternative to conventional hydraulic and mechanical snubbers for piping supports has attracted a wide interest among researchers and practitioners in the nuclear industry. The basic design concept of energy absorbers (EA) is to dissipate the vibration energy of piping systems through nonlinear hysteretic actions of EA!s under design seismic loads. Therefore, some type of nonlinear analysis needs to be performed in the seismic design of piping systems with EA supports. The equivalent linearization approach (ELA) can be a practical analysis tool for this purpose, particularly when the response approach (RSA) is also incorporated in the analysis formulations. In this paper, the following ELA/RSA methods are presented and compared to each other regarding their practice and numerical accuracy: Response approach using the square root of sum of squares (SRSS) approximation (denoted RS in this paper). Classical ELA based on modal combinations and linear random vibration theory (denoted CELA in this paper). Stochastic ELA based on direct solution of response covariance matrix (denoted SELA in this paper). New algorithms to convert response spectra to the equivalent power spectral density (PSD) functions are presented for both the above CELA and SELA methods. The numerical accuracy of the three EL are studied through a parametric error analysis. Finally, the practicality of the presented analysis is demonstrated in two application examples for piping systems with EA supports.
Application of GIS in siting of linear facilities
Gallagher, G.A. III; Heatwole, D.W.; Schmidt, J.A. )
1993-01-01
Geographic information systems (GIS) are powerful tools in the analysis and selection of environmentally acceptable corridors for linear facilities, such as roads and utility lines. GIS can serve several functions in corridor siting, including managing and manipulating extensive environmental databases, weighting and compositing data layers to enable spatial analysis for a path of least resistance,'' summarizing statistics for a comparison of alternative corridors, preparing color graphics for presentations and reports, and providing a record of alternative analysis for permitting reviews and legal challenges. In this paper, the authors examine the benefits and limitations of using GIS to site linear facilities, based mainly on their experience in siting a 600-mile natural gas pipeline in Florida. They implemented a phased analytical approach to define acceptable corridors several miles in width and then selected viable routes within the corridors using a magnified scale. This approach resulted in a dynamic siting process which required numerous iterations of analysis. Consequently, their experience has instilled the benefits derived by expending preliminary effort to create macros of the GIS analytical process so that subsequent effort is minimized during numerous iterations of corridor and route refinement.
Microfabricated linear Paul-Straubel ion trap
Mangan, Michael A.; Blain, Matthew G.; Tigges, Chris P.; Linker, Kevin L.
2011-04-19
An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.
Rf power sources for linear colliders
Allen, M.A.; Callin, R.S.; Caryotakis, G.; Deruyter, H.; Eppley, K.R.; Fant, K.S.; Farkas, Z.D.; Fowkes, W.R.; Hoag, H.A.; Feinstein, J.; Ko, K.; Koontz, R.F.; Kroll, N.M.; Lavine, T.L.; Lee, T.G.; Loew, G.A.; Miller, R.H.; Nelson, E.M.; Ruth, R.D.; Vlieks, A.E.; Wang, J.W.; Wilson, P.B. ); Boyd, J.K.; Houk, T.; Ryne, R.D.; Westenskow, G.A.; Yu, S.S. (Lawrence Live
1990-06-01
The next generation of linear colliders requires peak power sources of over 200 MW per meter at frequencies above 10 GHz at pulse widths of less than 100 nsec. Several power sources are under active development, including a conventional klystron with rf pulse compression, a relativistic klystron (RK) and a crossed-field amplifier. Power from one of these has energized a 0.5 meter two- section High Gradient Accelerator (HGA) and accelerated a beam at over 80 MeV meter. Results of tests with these experimental devices are presented here.
An optimal point spread function subtraction algorithm for high...
Office of Scientific and Technical Information (OSTI)
An optimal point spread function subtraction algorithm for high-contrast imaging: a ... This image is built as a linear combination of all available images and is optimized ...
Half-harmonic Kelvin probe force microscopy with transfer function...
Office of Scientific and Technical Information (OSTI)
Using linear and half-harmonic BE enables quantitative correction of the cantilever transfer function. Half-harmonic band excitation Kelvin probe force microscopy (HBE KPFM) thus ...
Measurement of W Boson Polarization in Top Quark Decay
Vickey, Trevor Neil
2004-11-01
A measurement of the polarization of the W boson from top quark decay is an excellent test of the V-A form of the charged-current weak interaction in the standard model. Since the longitudinal W boson is intimately related to the electroweak symmetry breaking mechanism, and the standard model gives a specific prediction for the fraction of longitudinal W bosons from top decays, it is of particular interest for study. This thesis presents a measurement of W boson polarization in top quark decays through an analysis of the cos{theta}* distribution in the lepton-plus-jets channel of t{bar t} candidate events from p{bar p} collisions at {radical}s = 1.96 TeV. This measurement uses an integrated luminosity of {approx} 162 pb{sup -1} of data collected with the CDF Run II detector, resulting in 31 t{bar t} candidate events with at least one identified b jet. Using a binned likelihood fit to the cos{theta}* distribution from the t{bar t} candidate events found in this sample, the fraction of W bosons with longitudinal polarization is determined to be F{sub 0} = 0.99{sub -0.35}{sup +0.29}(stat.) {+-} 0.19(syst.), F{sub 0} > 0.33 {at} 95% CL. This result is consistent with the standard model prediction, given a top quark mass of 174.3 GeV/c{sup 2}, of F{sub 0} = 0.701 {+-} 0.012.
Axial couplings and strong decay widths of heavy hadrons
William Detmold, C.-J. David Lin, Stefan Meinel
2012-04-01
We calculate the axial couplings of mesons and baryons containing a heavy quark in the static limit using lattice QCD. These couplings determine the leading interactions in heavy hadron chiral perturbation theory and are central quantities in heavy quark physics, as they control strong decay widths and the light-quark mass dependence of heavy hadron observables. Our analysis makes use of lattice data at six different pion masses, 227 MeV < m{sub {pi}} < 352 MeV, two lattice spacings, a = 0.085, 0.112 fm, and a volume of (2.7 fm){sup 3}. Our results for the axial couplings are g{sub 1} = 0.449(51), g{sub 2} = 0.84(20), and g{sub 3} = 0.71(13), where g{sub 1} governs the interaction between heavy-light mesons and pions and g{sub 2,3} are similar couplings between heavy-light baryons and pions. Using our lattice result for g{sub 3}, and constraining 1/m{sub Q} corrections in the strong decay widths with experimental data for {Sigma}{sub c}{sup (*)} decays, we obtain {Gamma}[{Sigma}{sub b}{sup (*)} {yields} {Lambda}{sub b} {pi}{sup {+-}}] = 4.2(1.0), 4.8(1.1), 7.3(1.6), 7.8(1.8) MeV for the {Sigma}{sub b}{sup +}, {Sigma}{sub b}{sup -}, {Sigma}{sub b}{sup *+}, {Sigma}{sub b}{sup *-} initial states, respectively. We also derive upper bounds on the widths of the {Xi}{sub b}{sup prime(*)} baryons.
Atomic nuclei decay modes by spontaneous emission of heavy ions
Poenaru, D.N.; Ivascu, M.; Sndulescu, A.; Greiner, W.
1985-08-01
The great majority of the known nuclides with Z>40, including the so-called stable nuclides, are metastable with respect to several modes of spontaneous superasymmetric splitting. A model extended from the fission theory of alpha decay allows one to estimate the lifetimes and the branching ratios relative to the alpha decay for these natural radioactivities. From a huge amount of systematic calculations it is concluded that the process should proceed with maximum intensity in the trans-lead nuclei, where the minimum lifetime is obtained from parent-emitted heavy ion combinations leading to a magic (/sup 208/Pb) or almost magic daughter nucleus. More than 140 nuclides with atomic number smaller than 25 are possible candidates to be emitted from heavy nuclei, with half-lives in the range of 10/sup 10/--10/sup 30/ s: /sup 5/He, /sup 8en-dash10/Be, /sup 11,12/B, /sup 12en-dash16/C, /sup 13en-dash17/N, /sup 15en-dash22/O, /sup 18en-dash23/F, /sup 20en-dash26/Ne, /sup 23en-dash28/Na, /sup 23en-dash30/Mg, /sup 27en-dash32/Al, /sup 28en-dash36/Si, /sup 31en-dash39/P, /sup 32en-dash42/S, /sup 35en-dash45/Cl, /sup 37en-dash47/Ar, /sup 40en-dash49/ K, . .Ca, /sup 44en-dash53/ Sc, /sup 46en-dash53/Ti, /sup 48en-dash54/V, and /sup 49en-dash55/ Cr. The shell structure and the pairing effects are clearly manifested in these new decay modes.
Limits on linearity of missile allocation optimization
Canavan, G.H.
1997-12-01
Optimizations of missile allocation based on linearized exchange equations produce accurate allocations, but the limits of validity of the linearization are not known. These limits are explored in the context of the upload of weapons by one side to initially small, equal forces of vulnerable and survivable weapons. The analysis compares analytic and numerical optimizations and stability induces based on aggregated interactions of the two missile forces, the first and second strikes they could deliver, and they resulting costs. This note discusses the costs and stability indices induced by unilateral uploading of weapons to an initially symmetrical low force configuration. These limits are quantified for forces with a few hundred missiles by comparing analytic and numerical optimizations of first strike costs. For forces of 100 vulnerable and 100 survivable missiles on each side, the analytic optimization agrees closely with the numerical solution. For 200 vulnerable and 200 survivable missiles on each side, the analytic optimization agrees with the induces to within about 10%, but disagrees with the allocation of the side with more weapons by about 50%. The disagreement comes from the interaction of the possession of more weapons with the shift of allocation from missiles to value that they induce.
Terahertz-driven linear electron acceleration
Nanni, Emilio A.; Huang, Wenqian R.; Hong, Kyung-Han; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Dwayne Miller, R. J.; Kärtner, Franz X.
2015-10-06
The cost, size and availability of electron accelerators are dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency accelerating structures operate with 30–50 MeVm^{-1 }gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional radio-frequency structures. However, laser-driven wakefield accelerators require intense femtosecond sources and direct laser-driven accelerators suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here we demonstrate linear acceleration of electrons with keV energy gain using optically generated terahertz pulses. Terahertz-driven accelerating structures enable high-gradient electron/proton accelerators with simple accelerating structures, high repetition rates and significant charge per bunch. As a result, these ultra-compact terahertz accelerators with extremely short electron bunches hold great potential to have a transformative impact for free electron lasers, linear colliders, ultrafast electron diffraction, X-ray science and medical therapy with X-rays and electron beams.
Terahertz-driven linear electron acceleration
Nanni, Emilio A.; Huang, Wenqian R.; Hong, Kyung-Han; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Dwayne Miller, R. J.; Kärtner, Franz X.
2015-10-06
The cost, size and availability of electron accelerators are dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency accelerating structures operate with 30–50 MeVm-1 gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional radio-frequency structures. However, laser-driven wakefield accelerators require intense femtosecond sources and direct laser-driven accelerators suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here we demonstrate linear acceleration of electrons with keV energy gain using optically generated terahertz pulses. Terahertz-driven accelerating structures enable high-gradient electron/proton acceleratorsmore » with simple accelerating structures, high repetition rates and significant charge per bunch. As a result, these ultra-compact terahertz accelerators with extremely short electron bunches hold great potential to have a transformative impact for free electron lasers, linear colliders, ultrafast electron diffraction, X-ray science and medical therapy with X-rays and electron beams.« less
Measurement of the Michel rho parameter in direct muon decay
Piilonen, Leo; Haim, D.; Zhang, Y.; Bolton, R.D.; Cooper, M.D.; Foreman, W.; Harrison, R.; Hart, G.; Hogan, G.E.; Kozlowski, T.; Kroupa, M.A.; Mischke, R.E.; Pillai, C.; Schilling, S.; Whitehouse, D.; Dzemidzic, M.; Hungerford, E.V.; Lan, K.; Mayes, B.W.; Pinsky, L.; von Witsch, W. Cooper, P.S.; Liu, F.; Tribble, R.E.; Tu, X.L.; Van Ausdeln, L.A.; Van Ausdeln, L.A. Jui, C.C.H.; Stantz, K.M.; Szymanski, J.J.; Manweiler, R.; Stanislaus, T.D.; Ziock, K.O.H. Wright, S.C.
1997-05-01
We report on the status of LAMPF experiment E-1240 to measure the Michel {rho} parameter in direct muon decay. This experiment ran in 1993, and the data are currently being analyzed. The expected precision on the {rho} parameter is {plus_minus}0.0008. This result will provide better constraints on new physics, particularly on the charged vector bosons{close_quote} mixing angle {zeta} in the manifestly left-right symmetric extension of the Standard Model. {copyright} {ital 1997 American Institute of Physics.}
Determination of the b_s lifetime using hadronic decays
Deisher, A.J.; /LBL, Berkeley
2008-07-01
The authors present a measurement of the B{sub s}{sup 0} meson lifetime using fully and partially reconstructed hadronic decays B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +}(X) followed by D{sub s}{sup -} {yields} {phi}{pi}{sup -}. The data sample was recorded with the CDF II detector at the Fermilab Tevatron and corresponds to an integrated luminosity of 1.3 fb{sup -1} from p{bar p} collisions at {radical}s = 1.96 TeV.
Reconstruction and identification of $\\tau$ lepton decays to hadrons and $\
Khachatryan, Vardan
2015-10-27
This paper describes the algorithms used by the CMS experiment to reconstruct and identify τ→ hadrons + v_{t} decays during Run 1 of the LHC. The performance of the algorithms is studied in proton-proton collisions recorded at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb^{-1}. The algorithms achieve an identification efficiency of 50–60%, with misidentification rates for quark and gluon jets, electrons, and muons between per mille and per cent levels.
Indoor radon and decay products: Concentrations, causes, and control strategies
Nero, A.V.; Gadgil, A.J.; Nazaroff, W.W.; Revzan, K.L.
1990-11-01
This report is another in the on going technical report series that addresses various aspects of the DOE Radon Research Program. It provides an overview of what is known about the behavior of radon and its decay products in the indoor environment and examines the manner in which several important classes of factors -- structural, geological, and meteorological -- affect indoor radon concentrations. Information on US indoor radon concentrations, currently available monitoring methods and novel radon control strategies are also explored. 238 refs., 22 figs., 9 tabs.
beta. -Decay in the Skyrme-Witten representation of QCD
Snyderman, N.J.
1991-05-01
The renormalized coupling strength of the {beta}-decay axial vector current is related to {pi}{plus minus} p cross sections through the Adler-Weisberger sum rule, that follows from chiral symmetry. We attempt to understand the Adler-Weisberger sum rule in the 1/N{sub c} expansion in QCD, and in the Skyrme-Witten model that realizes the 1/N{sub c} expansion in the low energy limit, using it to explicitly calculate both g{sub A} and the {pi}{plus minus} p cross sections. 32 refs.
Anatomy of exotic Higgs decays in 2HDM
Kling, Felix; No, Jose Miguel; Su, Shufang
2016-09-16
Large mass splittings between new scalars in two-Higgs-doublet models (2HDM) open a key avenue to search for these new states via exotic heavy Higgs decays. We discuss in detail the different search channels for these new scalars at the LHC in the presence of a sizable mass splitting, i.e. a hierarchical 2HDM scenario, taking into account the theoretical and experimental constraints. Here, we provide benchmark planes to exploit the complementarity among these searches, analyzing their potential to probe the hierarchical 2HDM parameter space during LHC Run 2.
Reconstruction and identification of $$\\tau$$ lepton decays to hadrons and $$\
Khachatryan, Vardan
2016-01-29
This paper describes the algorithms used by the CMS experiment to reconstruct and identify τ→ hadrons + vt decays during Run 1 of the LHC. The performance of the algorithms is studied in proton-proton collisions recorded at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb-1. The algorithms achieve an identification efficiency of 50–60%, with misidentification rates for quark and gluon jets, electrons, and muons between per mille and per cent levels.
Negative-parity states and {beta} decays in odd Ho and Dy nuclei with A=151,153
Al-Khudair, Falih H.; Long Guilu; Sun Yang
2008-03-15
We investigated the negative-parity states and electromagnetic transitions in {sup 151,153}Ho and {sup 151,153}Dy within the framework of the interacting boson fermion model 2 (IBFM-2). Spin assignments for some states with uncertain spin are made based on this calculation. Calculated excitation energies, electromagnetic transitions, and branching ratios are compared with available experimental data and a good agreement is obtained. The model wave functions were used to study {beta} decays from Ho to Dy isotones, and the calculated logft values are close to the experimental data.
Damping of linear waves via ionization and recombination in homogeneous plasmas
Dodin, I. Y.; Fisch, N. J.
2010-11-15
An oscillation-center model is proposed that analytically describes transformation of an arbitrary homogeneous linear wave at gradual ionization and recombination in homogeneous plasma. For the case when either of the processes dominates, general adiabatic invariants are found, from which the wave energy is derived as a function of the frequency.
Ledwig, Tim; Kim, Hyun-Chul; Goeke, Klaus
2008-09-01
We investigate the axial-vector transition constants of the baryon antidecuplet to the octet and decuplet within the framework of the self-consistent SU(3) chiral quark-soliton model. Taking into account rotational 1/N{sub c} and linear m{sub s} corrections and using the symmetry-conserving quantization, we calculate the axial-vector transition constants. It is found that the leading-order contributions are generally almost canceled by the rotational 1/N{sub c} corrections. Thus, the m{sub s} corrections turn out to be essential contributions to the axial-vector constants. The decay width of the {theta}{sup +}{yields}NK transition is determined to be {gamma}({theta}{yields}NK)=0.71 MeV, based on the result of the axial-vector transition constant g{sub A}*({theta}{yields}NK)=0.05. In addition, other strong decays of the baryon antidecuplet are investigated. The forbidden decays from the baryon antidecuplet to the decuplet are also studied.
Study of Rare B Meson Decays Related to the CKM Angle Beta at BaBar
Ulmer, Keith; /Amherst Coll.
2007-06-06
This study reports measurements of the branching fractions of B meson decays to {eta}{prime}K{sup +}, {eta}{prime}K{sup 0}, {omega}{pi}{sup +}, {omega}K{sup +}, and {omega}K{sup 0}. Charge asymmetries are measured for the charged modes and the time-dependent CP-violation parameters S and C are measured for the neutral modes. The results are based on a data sample of 347 fb{sup -1} containing 383 million B{bar B} pairs recorded by the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring located at the Stanford Linear Accelerator Center. Statistically significant signals are observed for all channels with the following results: B(B{sup +} {yields} {eta}{prime}K{sup +}) = (70.0{+-}1.5{+-}2.8)x10{sup -6}, B(B{sup 0} {yields} {eta}{prime}K{sup 0}) = (66.6{+-}2.6{+-}2.8)x10{sup -6}, B(B{sup +} {yields} {omega}{pi}{sup +}) = (6.7{+-}0.5{+-}0.4)x10{sup -6}, B(B{sup +} {yields} {omega}K{sup +}) = (6.3{+-}0.5{+-}0.3)x10-6, and B(B{sup 0} {yields} ?K0) = (5.6{+-}0.8{+-}0.3)x10-6, where the first uncertainty is statistical and the second is systematic. We measure A{sub ch}({eta}{prime}K{sup +}) = +0.010{+-}0.022{+-}0.006, A{sub ch}({omega}{pi}{sup +}) = -0.02{+-}0.08{+-}0.01, A{sub ch}({omega}K{sup +}) = -0.01{+-}0.07{+-}0.01, S{sub {eta}{prime}K{sup 0}{sub S}} = 0.56{+-}0.12{+-}0.02, C{sub {eta}{prime}K{sup 0}{sub S}} = -0.24 {+-} 0.08 {+-} 0.03, S{sub {omega}{prime}K{sup 0}{sub S}} = 0.62+0.25 -0.29 {+-} 0.02, and C{sub {omega}{prime}K{sup 0}{sub S}} = -0.39+0.25 -0.24 {+-} 0.03. The result in S{sub {eta}{prime}K{sup 0}{sub S}} contributes to the published measurement from BABAR, which differs from zero by 5.5 standard deviations and is the first observation of mixing-induced CP-violation in a charmless B decay.
Search for a light Higgs boson decaying to two gluons or ss? in the radiative decays of ?(1S)
Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Stugu, B.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; et al
2013-08-06
We search for the decay ?(1S)??A?, A??gg or ss?, where A? is the pseudoscalar light Higgs boson predicted by the next-to-minimal supersymmetric Standard Model. We use a sample of (17.60.3)10? ?(1S) mesons produced in the BABAR experiment via e?e???(2S)??????(1S). We see no significant signal and set 90%-confidence-level upper limits on the product branching fraction B(?(1S)??A?)B(A??gg or ss?) ranging from 10?? to 10? for A? masses in the range 0.59.0 GeV/c.
Time reversal invariance - a test in free neutron decay
Lising, Laura J.
1999-05-18
Time reversal invariance violation plays only a small role in the Standard Model, and the existence of a T-violating effect above the predicted level would be an indication of new physics. A sensitive probe of this symmetry in the weak interaction is the measurement of the T-violating ''D''-correlation in the decay of free neutrons. The triple-correlation D{sigma}{sub n}{center_dot}p{sub e} x p{sub v} involves three kinematic variables, the neutron spin, electron momentu, and neutrino (or proton) momentum, and changes sign under time reversal. This experiment detects the decay products of a polarized cold neutron beam with an octagonal array of scintillation and solid-state detectors. Data from first run at NIST's Cold Neutron Research Facility give a D-coefficient of -0.1 {+-} 1.3(stat.) {+-} 0.7(syst) x 10{sup -3}. This measurement has the greatest bearing on extensions to the Standard model that incorporate leptoquarks, although exotic fermion and lift-right symmetric models also allow a D as large as the present limit.
Search For B --> K* Nu Anti-Nu Decays
Aubert, B.
2008-08-15
We present a search for the decays B {yields} K* {nu}{bar {nu}} using 454 x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. We first select an event sample where one B is reconstructed in a semileptonic or hadronic mode with one charmed meson. The remaining particles in the event are then examined to search for a B {yields} K* {nu}{bar {nu}} decay. The charged K* is reconstructed as K*{sup +} {yields} K{sub S}{sup 0}{pi}{sup +} or K*{sup +} {yields} K{sup +}{pi}{sup 0}; the neutral K* is identified in K*{sup 0} {yields} K{sup +}{pi}{sup -} mode. We establish upper limits at 90% confidence level of {Beta}(B{sup +} {yields} K*{sup +} {nu}{bar {nu}}) < 8 x 10{sup -5}, {Beta}(B{sup 0} {yields} K*{sup 0} {nu}{bar {nu}}) < 12 x 10{sup -5}, and {Beta}(B {yields} K* {nu}{bar {nu}}) < 8 x 10{sup -5}.
Search for rare b-meson decays at CDF
Mack, Philipp; /Karlsruhe U., EKP
2007-10-01
We report on the search for B{sup 0}{sub s}{yields}{mu}{sup +}{mu}{sup -}, B{sup 0}{sub d}{yields}{mu}{sup +}{mu}{sup -} decays and b{yields} s{mu}{sup +}{mu}{sup -} transitions in exclusive decays of B mesons using the CDF II detector at the Fermilab Tevatron Collider. Using 2 fb{sup -1} of Run II data we find upper limits on the branching fractions {beta}(B{sup 0}{sub s}{yields}{mu}{sup +}{mu}{sup -})<5.8 x 10{sup -8} and {beta}(B{sup 0}{sub d}{yields}{mu}{sup +}{mu}{sup -})<1.8 x 10{sup -8} at 95% confidence level. The results for the branching fractions of the b{yields} s{mu}{sup +}{mu}{sup -} transitions using 924 pb{sup -1} of Run II data are {beta}(B{sup +}{yields}{mu}{sup +}{mu}{sup -}K{sup +})=(0.60{+-}0.15{+-}0.04) x 10{sup -6}, {beta}(B{sup 0}{sub d}{yields}{mu}{sup +}{mu}{sup -}K{sup *0})=(0.82{+-}0.31{+-}0.10) x 10{sup -6} and {beta}(B{sup 0}{sub s}{yields} {mu}{sup +}{mu}{sup -}{phi})/{beta}(B{sup 0}{sub s}{yields}J/{psi}{phi}) < 2.61 x 10{sup -3} at 95% confidence level.
Decaying leptophilic dark matter at IceCube
Boucenna, Sofiane M.; Chianese, Marco; Mangano, Gianpiero; Miele, Gennaro; Morisi, Stefano; Pisanti, Ofelia; Vitagliano, Edoardo
2015-12-29
We present a novel interpretation of IceCube high energy neutrino events (with energy larger than 60 TeV) in terms of an extraterrestrial flux due to two different contributions: a flux originated by known astrophysical sources and dominating IceCube observations up to few hundreds TeV, and a new flux component where the most energetic neutrinos come from the leptophilic three-body decays of dark matter particles with a mass of few PeV. Differently from other approaches, we provide two examples of elementary particle models that do not require extremely tiny coupling constants. We find the compatibility of the theoretical predictions with the IceCube results when the astrophysical flux has a cutoff of the order of 100 TeV (broken power law). In this case the most energetic part of the spectrum (PeV neutrinos) is due to an extra component such as the decay of a very massive dark matter component. Due to the low statistics at our disposal we have considered for simplicity the equivalence between deposited and neutrino energy, however such approximation does not affect dramatically the qualitative results. Of course, a purely astrophysical origin of the neutrino flux (no cutoff in energy below the PeV scale — unbroken power law) is still allowed. If future data will confirm the presence of a sharp cutoff above few PeV this would be in favor of a dark matter interpretation.
Dual-sensor technique for characterization of carrier lifetime decay transients in semiconductors
Ahrenkiel, R. K.; Johnston, S. W.; Kuciauskas, D.; Tynan, Jerry
2014-12-07
This work addresses the frequent discrepancy between transient photoconductive (PC) decay and transient photoluminescence (PL) decay. With this dual- sensor technique, one measures the transient PC and PL decay simultaneously with the same incident light pulse, removing injection-level uncertainty. Photoconductive decay measures the transient photoconductivity, Δσ(t). PCD senses carriers released from shallow traps as well as the photo-generated electron-hole pairs. In addition, variations in carrier mobility with injection level (and time) contribute to the decay time. PL decay senses only electron-hole recombination via photon emission. Theory and experiment will show that the time dependence of the two techniques can be quite different at high injection.
Competing decay modes of a high-spin isomer in the proton-unbound nucleus ??Ta*
Carroll, R. J.; Page, R. D.; Joss, D. T.; Uusitalo, J.; Darby, I. G.; Andgren, K.; Cederwall, B.; Eeckhaudt, S.; Grahn, T.; Gray-Jones, C.; Greenlees, P. T.; Hadinia, B.; Jones, P. M.; Julin, R.; Juutinen, S.; Leino, M.; Leppnen, A. -P.; Nyman, M.; O'Donnell, D.; Pakarinen, J.; Rahkila, P.; Sandzelius, M.; Sarn, J.; Scholey, C.; Seweryniak, D.; Simpson, J.
2015-01-01
An isomeric state at high spin and excitation energy was recently observed in the proton-unbound nucleus ^{158}Ta. This state was observed to decay by both ? and ? decay modes. The large spin change required to decay via ?-ray emission incurs a lifetime long enough for ? decay to compete. The ? decay has an energy of 8644(11) keV, which is among the highest observed in the region, a partial half-life of 440(70) ?s and changes the spin by 11?. In this study, additional evidence supporting the assignment of this ? decay to the high-spin isomer in ^{158}Ta will be presented.
Radio frequency focused interdigital linear accelerator
Swenson, Donald A.; Starling, W. Joel
2006-08-29
An interdigital (Wideroe) linear accelerator employing drift tubes, and associated support stems that couple to both the longitudinal and support stem electromagnetic fields of the linac, creating rf quadrupole fields along the axis of the linac to provide transverse focusing for the particle beam. Each drift tube comprises two separate electrodes operating at different electrical potentials as determined by cavity rf fields. Each electrode supports two fingers, pointing towards the opposite end of the drift tube, forming a four-finger geometry that produces an rf quadrupole field distribution along its axis. The fundamental periodicity of the structure is equal to one half of the particle wavelength .beta..lamda., where .beta. is the particle velocity in units of the velocity of light and .lamda. is the free space wavelength of the rf. Particles are accelerated in the gaps between drift tubes. The particle beam is focused in regions inside the drift tubes.
Faraday rotation assisted by linearly polarized light
Choi, Jai Min; Kim, Jang Myun; Cho, D.
2007-11-15
We demonstrate a type of chiral effect of an atomic medium. Polarization rotation of a probe beam is observed only when both a magnetic field and a linearly polarized coupling beam are present. We compare it with other chiral effects like optical activity, the Faraday effect, and the optically induced Faraday effect from the viewpoint of spatial inversion and time reversal transformations. As a theoretical model we consider a five-level configuration involving the cesium D2 transition. We use spin-polarized cold cesium atoms trapped in a magneto-optical trap to measure the polarization rotation versus probe detuning. The result shows reasonable agreement with a calculation from the master equation of the five-level configuration.
Sfermion precision measurements at a linear collider
A. Freitas et al.
2003-09-25
At future e{sup +}e{sup -} linear colliders, the event rates and clean signals of scalar fermion production--in particular for the scalar leptons--allow very precise measurements of their masses and couplings and the determination of their quantum numbers. Various methods are proposed for extracting these parameters from the data at the sfermion thresholds and in the continuum. At the same time, NLO radiative corrections and non-zero width effects have been calculated in order to match the experimental accuracy. The substantial mixing expected for the third generation sfermions opens up additional opportunities. Techniques are presented for determining potential CP-violating phases and for extracting tan {beta} from the stau sector, in particular at high values. The consequences of possible large mass differences in the stop and sbottom system are explored in dedicated analyses.
Linear nozzle with tailored gas plumes
Leon, David D.; Kozarek, Robert L.; Mansour, Adel; Chigier, Norman
2001-01-01
There is claimed a method for depositing fluid material from a linear nozzle in a substantially uniform manner across and along a surface. The method includes directing gaseous medium through said nozzle to provide a gaseous stream at the nozzle exit that entrains fluid material supplied to the nozzle, said gaseous stream being provided with a velocity profile across the nozzle width that compensates for the gaseous medium's tendency to assume an axisymmetric configuration after leaving the nozzle and before reaching the surface. There is also claimed a nozzle divided into respective side-by-side zones, or preferably chambers, through which a gaseous stream can be delivered in various velocity profiles across the width of said nozzle to compensate for the tendency of this gaseous medium to assume an axisymmetric configuration.
Linear nozzle with tailored gas plumes
Kozarek, Robert L.; Straub, William D.; Fischer, Joern E.; Leon, David D.
2003-01-01
There is claimed a method for depositing fluid material from a linear nozzle in a substantially uniform manner across and along a surface. The method includes directing gaseous medium through said nozzle to provide a gaseous stream at the nozzle exit that entrains fluid material supplied to the nozzle, said gaseous stream being provided with a velocity profile across the nozzle width that compensates for the gaseous medium's tendency to assume an axisymmetric configuration after leaving the nozzle and before reaching the surface. There is also claimed a nozzle divided into respective side-by-side zones, or preferably chambers, through which a gaseous stream can be delivered in various velocity profiles across the width of said nozzle to compensate for the tendency of this gaseous medium to assume an axisymmetric configuration.
Linear-array systems for aerospace NDE
Smith, Robert A.; Willsher, Stephen J.; Bending, Jamie M.
1999-12-02
Rapid large-area inspection of composite structures for impact damage and multi-layered aluminum skins for corrosion has been a recognized priority for several years in both military and civil aerospace applications. Approaches to this requirement have followed two clearly different routes: the development of novel large-area inspection systems, and the enhancement of current ultrasonic or eddy-current methods to reduce inspection times. Ultrasonic inspection is possible with standard flaw detection equipment but the addition of a linear ultrasonic array could reduce inspection times considerably. In order to investigate their potential, 9-element and 17-element linear ultrasonic arrays for composites, and 64-element arrays for aluminum skins, have been developed to DERA specifications for use with the ANDSCAN area scanning system. A 5 m{sup 2} composite wing surface has been scanned with a scan resolution of approximately 3 mm in 6 hours. With subsequent software and hardware improvements all four composite wing surfaces (top/bottom, left/right) of a military fighter aircraft can potentially be inspected in less than a day. Array technology has been very widely used in the medical ultrasound field although rarely above 10 MHz, whereas lap-joint inspection requires a pulse center-frequency of 12 to 20 MHz in order to resolve the separate interfaces in the lap joint. A 128 mm-long multi-element array of 5 mmx2 mm ultrasonic elements for use with the ANDSCAN scanning software was produced to a DERA specification by an NDT manufacturer with experience in the medical imaging field. This paper analyses the performance of the transducers that have been produced and evaluates their use in scanning systems of different configurations.
2d PDE Linear Symmetric Matrix Solver
Energy Science and Technology Software Center (OSTI)
1983-10-01
ICCG2 (Incomplete Cholesky factorized Conjugate Gradient algorithm for 2d symmetric problems) was developed to solve a linear symmetric matrix system arising from a 9-point discretization of two-dimensional elliptic and parabolic partial differential equations found in plasma physics applications, such as resistive MHD, spatial diffusive transport, and phase space transport (Fokker-Planck equation) problems. These problems share the common feature of being stiff and requiring implicit solution techniques. When these parabolic or elliptic PDE''s are discretized withmore » finite-difference or finite-element methods,the resulting matrix system is frequently of block-tridiagonal form. To use ICCG2, the discretization of the two-dimensional partial differential equation and its boundary conditions must result in a block-tridiagonal supermatrix composed of elementary tridiagonal matrices. The incomplete Cholesky conjugate gradient algorithm is used to solve the linear symmetric matrix equation. Loops are arranged to vectorize on the Cray1 with the CFT compiler, wherever possible. Recursive loops, which cannot be vectorized, are written for optimum scalar speed. For matrices lacking symmetry, ILUCG2 should be used. Similar methods in three dimensions are available in ICCG3 and ILUCG3. A general source containing extensions and macros, which must be processed by a pre-compiler to obtain the standard FORTRAN source, is provided along with the standard FORTRAN source because it is believed to be more readable. The pre-compiler is not included, but pre-compilation may be performed by a text editor as described in the UCRL-88746 Preprint.« less
International linear collider reference design report
Aarons, G.
2007-06-22
The International Linear Collider will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. A proposed electron-positron collider, the ILC will complement the Large Hadron Collider, a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, together unlocking some of the deepest mysteries in the universe. With LHC discoveries pointing the way, the ILC -- a true precision machine -- will provide the missing pieces of the puzzle. Consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 35 kilometres in length, the beams collide 14,000 times every second at extremely high energies -- 500 billion-electron-volts (GeV). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV) machine during the second stage of the project. This reference design provides the first detailed technical snapshot of the proposed future electron-positron collider, defining in detail the technical parameters and components that make up each section of the 31-kilometer long accelerator. The report will guide the development of the worldwide R&D program, motivate international industrial studies and serve as the basis for the final engineering design needed to make an official project proposal later this decade.
keV sterile neutrino dark matter from singlet scalar decays: basic concepts and subtle features
Merle, Alexander; Totzauer, Maximilian
2015-06-08
We perform a detailed and illustrative study of the production of keV sterile neutrino Dark Matter (DM) by decays of singlet scalars in the early Universe. In the current study we focus on providing a clear and general overview of this production mechanism. For the first time we study all regimes possible on the level of momentum distribution functions, which we obtain by solving a system of Boltzmann equations. These quantities contain the full information about the production process, which allows us to not only track the evolution of the DM generation but to also take into account all bounds related to the spectrum, such as constraints from structure formation or from avoiding too much dark radiation. In particular we show that this simple production mechanism can, depending on the regime, lead to strongly non-thermal DM spectra which may even feature more than one peak in the momentum distribution. These cases could have particularly interesting consequences for cosmological structure formation, as their analysis requires more refined tools than the simplistic estimate using the free-streaming horizon. Here we present the mechanism including all concepts and subtleties involved, for now using the assumption that the effective number of relativistic degrees of freedom is constant during DM production, which is applicable in a significant fraction of the parameter space. This allows us to derive analytical results to back up our detailed numerical computations, thus leading to the most comprehensive picture of keV sterile neutrino DM production by singlet scalar decays that exists up to now.
Quantum Decay of the 'False Vacuum' and Pair Creation of Soliton Domain Walls
Miller, John H. Jr.
2011-03-28
Quantum decay of metastable states ('false vacua') has been proposed as a mechanism for bubble nucleation of new universes and phase transitions in the early universe. Experiments indicate the occurrence of false vacuum decay, within a region bounded by soliton domain walls that nucleate via quantum tunneling, in a highly anisotropic condensed matter system. This phenomenon provides a compelling example of false vacuum decay in the laboratory.
Double beta decay versus cosmology: Majorana CP phases and nuclear matrix elements
Deppisch, Frank; Paes, Heinrich [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, D-97074 Wuerzburg (Germany); Suhonen, Jouni [Department of Physics, University of Jyvaeskylae, P.O.B. 35, FIN-40014, Jyvaeskylae (Finland)
2005-08-01
We discuss the relation between the absolute neutrino mass scale, the effective mass measured in neutrinoless double beta decay, and the Majorana CP phases. Emphasis is placed on estimating the upper bound on the nuclear matrix element entering calculations of the double beta decay half-life. Combining the claimed evidence for neutrinoless double beta decay with the neutrino mass bound from cosmology, one of the Majorana CP phases can be constrained.
Shell model nuclear matrix elements for competing mechanisms contributing to double beta decay
Horoi, Mihai
2013-12-30
Recent progress in the shell model approach to the nuclear matrix elements for the double beta decay process are presented. This includes nuclear matrix elements for competing mechanisms to neutrionless double beta decay, a comparison between closure and non-closure approximation for {sup 48}Ca, and an updated shell model analysis of nuclear matrix elements for the double beta decay of {sup 136}Xe.
Rare top quark decays in Alternative Left-Right Symmetric Models
Gaitan, R.; Miranda, O. G.; Cabral-Rosetti, L. G.
2007-06-19
We evaluate the flavor changing neutral currents (FCNC) decay t {yields} H0 + c in the context of Alternative Left-Right symmetric Models (ALRM) with extra isosinglet heavy fermions; the FCNC decays may place at tree level and are only supressed by the mixing between ordinary top and charm quarks. We also comment on the decay process t {yields} c + {gamma}, which involves radiative corrections.
-delayed ?-proton decay in ??Zn: Analysis of the charged-particle spectrum
Orrigo, S. E.A.; Rubio, B.; Fujita, Y.; Blank, B.; Agramunt, J.; Algora, A.; Ascher, P.; Cceres, L.; Cakirli, R. B.; Fujita, H.; Ganio?lu, E.; Gerbaux, M.; Kozer, H. C.; Kucuk, L.; Kurtukian-Nieto, T.; Popescu, L.; Rogers, A. M.; Susoy, G.; Stodel, C.; Suzuki, T.; Tamii, A.; Thomas, J. C.
2015-01-01
A study of the ? decay of the proton-rich T_{z} = 2 nucleus ??Zn has been reported in a recent publication. A rare and exotic decay mode, ?-de-layed ?-proton decay, has been observed there for the first time in the fp shell. Here, we expand on some of the details of the data analysis, focusing on the charged particle spectrum.
CALiPER Application Summary Report 19. LED Linear Pendants
none,
2012-10-01
Report 19 reviews the independently tested performance of nine LED linear pendants and also evaluates a collection of 11 linear pendant products available in both an LED and fluorescent version.
Project Profile: Commercial Development of an Advanced Linear...
Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)
Project Profile: Commercial Development of an Advanced Linear-Fresnel-Based CSP Concept SkyFuel logo SkyFuel, under the CSP R&D FOA, is developing a commercial linear-Fresnel-based ...
Layden, B.; Cairns, Iver H.; Robinson, P. A.
2013-08-15
Electrostatic decay of Langmuir waves into Langmuir and ion sound waves (L?L?+S) and scattering of Langmuir waves off thermal ions (L+i?L?+i?, also called nonlinear Landau damping) are important nonlinear weak-turbulence processes. The rates for these processes depend on the quadratic longitudinal response function ?{sup (2)} (or, equivalently, the quadratic longitudinal susceptibility ?{sup (2)}), which describes the second-order response of a plasma to electrostatic wave fields. Previous calculations of these rates for an unmagnetized Maxwellian plasma have relied upon an approximate form for ?{sup (2)} that is valid where two of the wave fields are fast (i.e., v{sub ?}=?/k?V{sub e} where ? is the angular frequency, k is the wavenumber, and V{sub e} is the electron thermal speed) and one is slow (v{sub ?}?V{sub e}). Recently, an exact expression was derived for ?{sup (2)} that is valid for any phase speeds of the three waves in an unmagnetized Maxwellian plasma. Here, this exact ?{sup (2)} is applied to the calculation of the three-dimensional rates for electrostatic decay and scattering off thermal ions, and the resulting exact rates are compared with the approximate rates. The calculations are performed using previously derived three-dimensional rates for electrostatic decay given in terms of a general ?{sup (2)}, and newly derived three-dimensional rates for scattering off thermal ions; the scattering rate is derived assuming a Maxwellian ion distribution, and both rates are derived assuming arc distributions for the wave spectra. For most space plasma conditions, the approximate rate is found to be accurate to better than 20%; however, for sufficiently low Langmuir phase speeds (v{sub ?}/V{sub e}?3) appropriate to some spatial domains of the foreshock regions of planetary bow shocks and type II solar radio bursts, the use of the exact rate may be necessary for accurate calculations. The relative rates of electrostatic decay and scattering off thermal ions
Text-Alternative Version: LED Replacements for Linear Fluorescent Lamps |
Department of Energy Replacements for Linear Fluorescent Lamps Text-Alternative Version: LED Replacements for Linear Fluorescent Lamps Below is the text-alternative version of the "LED Replacements for Linear Fluorescent Lamps" webcast, held June 20, 2011. Theresa Shoemaker: Welcome, ladies and gentlemen. I'm Terry Shoemaker with the Pacific Northwest National Laboratory, and I'd like to welcome you to today's webcast, "LED Replacements for Linear Fluorescent Lamps,"
Charmless Three-Body $B$ Decays at BABAR (Conference) | SciTech...
Office of Scientific and Technical Information (OSTI)
Conference: Charmless Three-Body B Decays at BABAR Citation Details In-Document Search ... Country of Publication: United States Language: English Subject: Experiment-HEP,HEPEX Word ...
On the use of Extreme Value Theory in analyses of continuum gamma decay
Garcia-Ruiz, R. F.; Cristancho, F.
2010-08-04
Extreme Value theory seems to be a promising tool for analysing experimental continuum gamma decay spectra in order to obtain physical parameters at high excitation energy.
On the ability of Order Statistics to distinguish different models for continuum gamma decay
Sandoval, J. J.; Cristancho, F.
2007-10-26
A simulation procedure to calculate some important parameters to the application of Order Statistics in the analysis of continuum gamma decay is presented.
Using NERSC Systems, Physicists Close In on a Rare-Particle Decay...
U.S. Department of Energy (DOE) all webpages (Extended Search)
Observatory experiment (EXO-200) has placed the most stringent constraints yet on the nature of a process called neutrinoless double beta decay. In doing so, the physicists have...
Double Beta Decay in Xenon-136: Measuring the Neutrino-Emitting...
Office of Scientific and Technical Information (OSTI)
Title: Double Beta Decay in Xenon-136: Measuring the Neutrino-Emitting Mode and Searching for Majoron-Emitting Modes Authors: Herrin, Steven ; Stanford U., Phys. Dept. SLAC ...
Energy Science and Technology Software Center (OSTI)
1981-09-04
Version 00 THIDA-2 calculates transmutation, radioactivity, decay heat and dose rate for a fusion reactor using one-, two-, and three-dimensional geometrical models.
Searching for Neutrinoless Double-Beta Decay of 130 Te with CUORE...
Office of Scientific and Technical Information (OSTI)
Neutrinoless double-beta (0 ) decay is a hypothesized lepton-number-violating process that offers the only known means of asserting the possible Majorana nature of ...
Neutrinoless Double Beta Decay in Light of SNO Salt Data (Journal...
Office of Scientific and Technical Information (OSTI)
Dirac neutrinos if the invertedor degenerate mass spectrum will be confirmed by the improvements in cosmology, tritium data beta decay, or long-baseline oscillation experiments. ...
Large Hadron Collider Probe of Supersymmetric Neutrinoless Double-Beta-Decay Mechanism
Allanach, B. C.; Kom, C. H.; Paes, H. [DAMTP, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom); Cavendish Laboratory, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Fakultaet fuer Physik, Technische Universitaet Dortmund, D-44221, Dortmund (Germany)
2009-08-28
In the minimal supersymmetric extension to the standard model, a nonzero lepton number violating coupling {lambda}{sub 111}{sup '} predicts both neutrinoless double-beta-decay and resonant single slepton production at the LHC. We show that, in this case, if neutrinoless double beta decay is discovered in the next generation of experiments, there exist good prospects to observe single slepton production at the LHC. Neutrinoless double beta decay could otherwise result from a different source (such as a nonzero Majorana neutrino mass). Resonant single slepton production at the LHC can therefore discriminate between the {lambda}{sub 111}{sup '} neutrinoless double-beta-decay mechanism and others.
Khotilovich, Vadim, G.; /Texas A-M
2008-05-01
I present the results of a search for pair production of scalar top quarks ({tilde t}{sub 1}) in an R-parity violating supersymmetric scenario using 322 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected by the upgraded Collider Detector at Fermilab. I assume each {tilde t}{sub 1} decays into a {tau} lepton and a b quark, with branching ratio {beta}, and search for final states containing either an electron or a muon from a leptonic {tau} decay, a hadronically decaying {tau} lepton, and two or more jets. Two candidate events pass my final selection criteria, consistent with the expectation from standard model processes. I present upper limits on the cross section times branching ratio squared {sigma}({tilde t}{sub 1}{bar {tilde t}}{sub 1}) x {beta}{sup 2} as a function of the stop mass m({tilde t}{sub 1}). Assuming {beta} = 1, I set a 95% confidence level limit m({tilde t}{sub 1}) > 153 GeV=c{sup 2}. These limits are also fully applicable to the case of a pair produced third generation scalar leptoquark that decays into a {tau} lepton and a b quark.