Results for "K. Godbey"

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Dependence of fusion on isospin dynamicsSep 27 2016We introduce a new microscopic approach to calculate the dependence of fusion barriers and cross-sections on isospin dynamics. The method is based on the time-dependent Hartree-Fock theory and the isoscalar and isovector properties of the energy density ... More
Equilibration dynamics and isospin effects in nuclear reactionsApr 12 2019We discuss equilibration times and isospin effect for various quantities in low-energy heavy-ion reactions. These include equilibration of mass, isospin, and total kinetic energy (TKE) in quasifission and deep-inelastic reactions. The calculations are ... More
Deformed shell effects in $^{48}$Ca+$^{249}$Bk quasifission fragmentsJun 18 2019Background: Quasifission is the main reaction channel hindering the formation of superheavy nuclei (SHN). Its understanding will help to optimize entrance channels for SHN studies. Quasifission also provides a probe to understand the influence of shell ... More
Absence of hindrance in microscopic $^{12}$C+$^{12}$C fusion studyJun 05 2019Background: Studies of low-energy fusion of light nuclei are important in astrophysical modeling, with small variations in reaction rates having a large impact on nucleosynthesis yields. Due to the lack of experimental data at astrophysical energies, ... More
How the Pauli exclusion principle affects fusion of atomic nucleiOct 09 2016The Pauli exclusion principle induces a repulsion between composite systems of identical fermions such as colliding atomic nuclei. Our goal is to study how heavy-ion fusion is impacted by this "Pauli repulsion". We propose a new microscopic approach, ... More
Effect of Pauli repulsion and transfer on fusionMay 31 2017The effect of the Pauli exclusion principle on the nucleus-nucleus bare potential is studied using a new density-constrained extension of the Frozen-Hartree-Fock (DCFHF) technique. The resulting potentials exhibit a repulsion at short distance. The charge ... More
Light exotic nuclei with extreme neutron excess and $2 \leq z \leq 8$Apr 15 2015Using HF+BCS method we study light nuclei with nuclear charge in the range $2 \leq Z \leq 8$ and lying near the neutron drip line. The HF method uses effective Skyrme forces and allows for axial deformations. We find that the neutron drip line forms stability ... More
New CLEO II Results on Charm Hadron DecaysFeb 04 2002We present new results on charm hadron decays from the CLEO II experiment. The D*+ width is measured for the first time, Gamma(D*+) = 96 +- 4 +- 22 keV. The semileptonic decay branching fractions are determined to be B(D+ --> Kbar*0 e+ nu_e) = (6.7 +- ... More
Tau2000 Conference SummaryMar 10 2001This is a review of some of the highlights of the 6th workshop on the physics of the tau lepton and its neutrino. This includes the test of lepton universality, measurement of Lorentz Structure, study of hadronic decays, direct evidence of tau neutrino, ... More
Image charge effects in single-molecule junctions: Breaking of symmetries and negative differential resistance in a benzene transistorApr 13 2011Aug 11 2011Both experiments and theoretical studies have demonstrated that the interaction between the current carrying electrons and the induced polarization charge in single-molecule junctions leads to a strong renormalization of molecular charging energies. However, ... More
Detecting activity cycles of late-type dwarfs in Kepler dataAug 12 2013Using data of fast-rotating active dwarf stars in the Kepler database, we perform time-frequency analysis of the light curves in order to search for signs of activity cycles. We use the phenomenon that the active region latitudes vary with the cycle (like ... More
Unitarity of the SoV transform for the Toda chainJun 20 2013May 04 2015The quantum separation of variables method consists in mapping the original Hilbert space where a spectral problem is formulated onto one where the spectral problem takes a simpler "separated" form. In order to realise such a program, one should construct ... More
Truncated Wiener-Hopf operators with Fisher Hartwig singularitiesMay 26 2008Jan 20 2010We derive the asymptotic behavior of determinants of truncated Wiener-Hopf operators generated by symbols having Fisher-Hartwig singularities. This task is achieved thanks to an asymptotic resolution of the Riemann-Hilbert problem associated to some generalized ... More
Near-threshold $ω$ and $φ$ meson productions in $pp$ collisionsApr 05 2003Jul 01 2003Using a relativistic effective Lagrangian at the hadronic level, near-threshold $\omega$ and $\phi$ meson productions in proton proton ($pp$) collisions, $p p \to p p \omega/\phi$, are studied within the distorted wave Born approximation. Both initial ... More
Near-threshold $ω$-meson production in proton-proton collisions: With or without resonance excitations ?Nov 21 2002Dec 12 2002We present results for the $p p \to p p \omega$ reaction studied by considering two different scenarios: with and without the inclusion of nucleon resonance excitations. The recently measured angular distribution by the COSY-TOF Collaboration at an excess ... More
Time-dependent Hartree-Fock plus Langevin approach for hot fusion reactions to synthesize the superheavy element with $Z=120$Mar 15 2019We develop a novel approach to fusion reactions for syntheses of superheavy elements, which combines the time-dependent Hartree-Fock (TDHF) method with a dynamical diffusion model based on the Langevin equation. In this approach, the distance of the closest ... More
Jets and Black Holes in Hypernova ExplosionsMay 12 2003Bipolar explosion models for hypernovae (very energetic supernovae), associated with the black hole formation, are presented. The model features are as follows: (1) Fe-peak elements are ejected at high velocities to reach the surface region, while dense ... More
Nowhere differentiable functions with respect to the positionJan 17 2017Let $\Omega$ be a bounded domain in $\mathbb{C}$ such that $\partial \Omega$ does not contain isolated points. Let $R(\Omega)$ be the space of uniform limits on $\overline{\Omega}$ of rational functions with poles off $\overline{\Omega}$, endowed with ... More
A new method of measuring the half-life of ^{10}CNov 27 2009A new measurement of the half-life of the positron emitter 10C has been made. The 10C decay belongs to the set of superallowed 0+ -> 0+ beta-decays whose Ft values offer stringent tests of the Conserved Vector Current (CVC) hypothesis and which can be ... More
Implications of detecting the Axion-Like Particles in Astro-Particle PhysicsMay 13 2019Axions and axion like particles in general are consequences of the extensions of the standard model in particle physics. Axions have been proposed as hypothetical pseudo-scalar particles in particle physics to solve the strong Charge-Parity problem using ... More
On non-exponential cosmological solutions with two factor spaces of dimensions $m$ and $ 1$ in the Einstein-Gauss-Bonnet model with a $Λ$-termMay 30 2019We consider a $(m+2)$-dimensional Einstein-Gauss-Bonnet model with the cosmological $\Lambda$-term. We restrict the metrics to be diagonal ones and find for certain $\Lambda = \Lambda(m)$ class of cosmological solutions with non-exponential time dependence ... More
On Form Factors of the conjugated field in the non-linear Schröodinger modelMay 05 2011Izergin-Korepin's lattice discretization of the non-linear Schr\"odinger model along with Oota's inverse problem provides one with determinant representations for the form factors of the lattice discretized conjugated field operator. We prove that these ... More
High Kondo temperature (TK ~ 80 K) in self-assembled InAs quantum dots laterally coupled to nanogap electrodesAug 19 2008We have fabricated single electron tunneling structures by forming nanogap metallic electrodes directly upon single self-assembled InAs quantum dots (QDs). The fabricated samples exhibited clear Coulomb blockade effects. Furthermore, a clear Kondo effect ... More
Probing internucleus potential with large-angle quasi-elastic scatteringMay 08 2006Recent measurements for fusion cross section at energies around the Coulomb barrier have systematically indicated a significant deviation of fusion cross sections from a prediction of double-folding model. It has been argued that the deviation can be ... More
Microscopic Theory of Trapped Two-Dimensional Bose GasMar 29 2005This report is based on my incomplete Phd thesis. The final part of the work on the 2D Yukawa bosons/vortices in a confined geometry is not complete and subject to futher development.
New Results on ATLAS Pixel Opto-LinkJan 30 2002We present new results on the optical link for the pixel detector of the ATLAS experiment. An optical package of novel design has been developed for the opto-link. The design is based on a simple connector-type concept and is made of radiation-hard material. ... More
A Novel Optical Package for ATLAS Pixel DetectorMar 10 2001An optical package of novel design has been developed for the ATLAS pixel detector. The package contains two VCSELs and one PIN diode to transmit and receive optical signals. The design is based on a simple connector-type concept and is made of radiation-hard ... More
Radiation-Hard Optical Link for SLHCDec 29 2008We study the feasibility of fabricating an optical link for the SLHC ATLAS silicon tracker based on the current pixel optical link architecture. The electrical signals between the current pixel modules and the optical modules are transmitted via micro-twisted ... More
An MT-Style Optical Package for Optical Data TransmissionMar 03 2003An optical package for mounting VCSEL and PIN diodes for transmitting and receiving optical signals has been developed. The diodes couple to the fibers in a commercial MT connector. The package is quite compact with its physical size significantly smaller ... More
Thermodynamic Phase Diagram of the Quantum Hall Skyrmion SystemAug 22 1999We numerically study the interacting quantum Hall skyrmion system based on the Chern-Simons action. By noticing that the action is invariant under global spin rotations in the spin space with respect to the magnetic field direction, we obtain the low-energy ... More
Approximate symmetries of geodesic equations on 2-spheresMay 09 2010Approximate symmetries of geodesic equations on 2-spheres are studied. These are the symmetries of the perturbed geodesic equations which represent approximate path of a particle rather than exact path. After giving the exact symmetries of the geodesic ... More
Combination of thermal and electric properties measurement techniques in a single setup suitable for radioactive materials in controlled environments and based on the 3-omega approachApr 03 2018We have designed and developed a new experimental setup, based on the 3-omega method, to measure thermal conductivity, heat capacity and electrical resistivity of a variety of samples in a broad temperature range (2-550 K) and under magnetic fields up ... More
Machine learning materials physics: Deep neural networks trained on elastic free energy data from martensitic microstructures predict homogenized stress fields with high accuracyJan 02 2019We present an approach to numerical homogenization of the elastic response of microstructures. Our work uses deep neural network representations trained on data obtained from direct numerical simulation (DNS) of martensitic phase transformations. The ... More
A Probabilistic Proof of the Multinomial TheoremAug 04 2016In this note, we give an alternate proof of the multinomial theorem using a probabilistic approach. Although the multinomial theorem is basically a combinatorial result, our proof may be simpler for a student familiar with only basic probability concepts. ... More
Radiation-Hard Asics for Optical Data Transmission in the Atlas Pixel DetectorAug 10 2004We have developed two radiation-hard ASICs for optical data transmission in the ATLAS pixel detector at the LHC at CERN: a driver chip for a Vertical Cavity Surface Emitting Laser (VCSEL) diode for 80 Mbit/s data transmission from the detector, and a ... More
Radiation-hard ASICs for optical data transmission in the ATLAS pixel detectorMar 13 2003We have developed two radiation-hard ASICs for optical data transmission in the ATLAS pixel detector at the LHC at CERN: a driver chip for a Vertical Cavity Surface Emitting Laser (VCSEL) diode for 80 Mbit/s data transmission from the detector, and a ... More
Incorporation of the statistical uncertainty in the background estimate into the upper limit on the signalJul 25 1997We present a procedure for calculating an upper limit on the number of signal events which incorporates the Poisson uncertainty in the background, estimated from control regions of one or two dimensions. For small number of signal events, the upper limit ... More
Optical Link of the Atlas Pixel DetectorDec 06 2007The on-detector optical link of the ATLAS pixel detector contains radiation-hard receiver chips to decode bi-phase marked signals received on PIN arrays and data transmitter chips to drive VCSEL arrays. The components are mounted on hybrid boards (opto-boards). ... More
Search for Neutrinoless Tau Decays Involving the K0 MesonNov 11 2002We have searched for lepton flavor violating decays of the tau lepton with one or two KS0 mesons in the final state. The data used in the search were collected with the CLEO II and II.V detectors at the Cornell Electron Storage Ring (CESR) and correspond ... More
High-resolution spectroscopy of the intermediate polar EX Hydrae. I. Kinematic study and Roche tomographyFeb 18 2008EX Hya is one of the few double-lined eclipsing cataclysmic variables that allow an accurate measurement of the binary masses. We analyze orbital phase-resolved UVES/ VLT high resolution spectroscopic observations of EX Hya with the aims of deriving the ... More
Near-IR Properties of Quasar Host GalaxiesJan 23 1997We have obtained deep, near-IR images of nearly 100 host galaxies of nearby quasars and Seyferts. We find the near-IR light to be a good tracer of luminous mass in these galaxies. For the most luminous quasars there is a correlation between the maximum ... More
Evolution of Low Mass Contact BinariesJul 17 2012We present a study on low-mass contact binaries (LMCB) with orbital periods shorter than 0.3 days and total mass lower than about 1.4 solar mass. We show that such systems have a long pre-contact phase, which lasts for 8-9 Gyrs, while the contact phase ... More
Deformation of Fermi Surface Due to Antiferromagnetic CorrelationDec 16 1999It is investigated, on the basis of the fluctuation exchange approximation, how the shape of the Fermi surface is modified in two-dimensional $t-t'-U$ Hubbard model at half filling as strength of the onsite Coulomb interaction $U$ is increased. The antiferromagnetic ... More
On condensation properties of Bethe roots associated with the XXZ chainAug 24 2015I prove that the Bethe roots describing either the ground state or a certain class of "particle-hole" excited states of the XXZ spin-$1/2$ chain in any sector with magnetisation $\mathfrak{m} \in [0;1/2]$ exist and form, in the infinite volume limit, ... More
Large-distance and long-time asymptotic behavior of the reduced density matrix in the non-linear Schrödinger modelJan 08 2011May 05 2011Starting from the form factor expansion in finite volume, we derive the multidimensional generalization of the so-called Natte series for the zero-temperature, time and distance dependent reduced density matrix in the non-linear Schr\"{o}dinger model. ... More
On the emptiness formation probability of the open XXZ spin-$\tf{1}{2}$ chainAug 02 2007This paper is devoted to the study of the emptiness formation probability $\tau\pa{m}$ of the open XXZ chain. We derive a closed form for $\tau\pa{m}$ at $\Delta=\tf{1}{2}$ when the boundary field vanishes. Moreover we obtain its leading asymptotics for ... More
Multiplicity with a Thrust CutDec 28 1993We evaluate the multiplicity of hadrons in the $e^+e^-$-annihilation at a given thrust $T$ in the modified leading-log approximation, including $O(\sqrt{\alpha_s})$ corrections. The calculation is done at a large value of $\tau =1-T$ by the use of the ... More
Theory of Ultrasonic Dispersion in Local Phonon Systems Coupled with Conduction ElectronsJul 25 2007The physical origin of frequency dependence in elastic constants, which are often found in an ultrasound propagation in filled skutterudites and clathrate compounds, is investigated theoretically. This dependence arises from a coupling between the acoustic ... More
Semiclassical expansion of the Slater sum for position dependent mass distributions in d dimensionsOct 04 2012Apr 26 2013We consider hamiltonian systems with spatially varying effective mass and slowly varying local potential in d dimensions. The Slater sum is defined as the diagonal element of the Bloch propagator. We derive a gradient expansion of the Slater sum up to ... More
Bipolar Supernova Explosions: Nucleosynthesis & Implication on Abundances in Extremely Metal-Poor StarsApr 09 2003Aug 08 2003Hydrodynamics and explosive nucleosynthesis in bipolar supernova explosions are examined to account for some peculiar properties of hypernovae as well as peculiar abundance patterns of metal-poor stars. The explosion is supposed to be driven by bipolar ... More
Scale Factors of Homogeneous Anisotropic Cosmological Models with Perfect FluidJun 07 2019The article is devoted to cosmology. It deals with homogeneous anisotropic cosmological models. Scale factors have been evaluated for the multicomponent models with perfect fluid, taking account of its expansion, rotation and shear. The cosmological fluid ... More
Zeros of the hypergeometric polynomial F(-n,b;c;z)Dec 03 2008Our interest lies in describing the zero behaviour of Gauss hypergeometric polynomials $F(-n,b; c; z)$ where $b$ and $c$ are arbitrary parameters. In general, this problem has not been solved and even when $b$ and $c$ are both real, the only cases that ... More
Multi-objective Geometric Programming Problem With Weighted Mean MethodMar 07 2010Geometric programming is an important class of optimization problems that enable practitioners to model a large variety of real-world applications, mostly in the field of engineering design. In many real life optimization problem multi-objective programming ... More
On a certain class of $\K$ Banach spacesApr 24 2013Using a strengthening of the concept of $\K$ set, introduced in this paper, we study a certain subclass of the class of $\K$ Banach spaces; the so called strongly $\K$ Banach spaces. This class of spaces includes subspaces of strongly weakly compactly ... More
Vertex Operators for Super Yang-Mills and Multi D-Branes in Green-Schwarz SuperstringDec 26 1996Jan 10 1997We study vertex operators for super Yang-Mills and multi D-branes in covariant form using Green-Schwarz formalism. We introduce the contact terms naturally and prove space-time supersymmetry and gauge invariance. The nonlinear realization of broken supersymmetry ... More
Search for neutrino charged current coherent pion production at SciBooNESep 28 2009SciBooNE is a neutrino experiment measuring the neutrino cross sections on carbon in the one GeV region. We have performed a search for charged current coherent pion production from muon neutrinos scattering on carbon, \nu_\mu 12^C \to \mu 12^C \pi^+. ... More
Hyperfine structure in $^{229g}$Th$^{3+}$ as a probe of the $^{229g}$Th $\rightarrow$ $^{229m}$Th nuclear excitation energyFeb 13 2014We identify a potential means to extract the $^{229g}$Th $\rightarrow$ $^{229m}$Th nuclear excitation energy from precision microwave spectroscopy of the $5F_{5/2,7/2}$ hyperfine manifolds in the ion $^{229g}$Th$^{3+}$. The hyperfine interaction mixes ... More
Short Baseline Accelerator-Based Neutrino Oscillation SearchesSep 11 2002We review the status of the search for neutrino oscillations in the short baseline regime with experiments at accelerators. The evidence for numubar->nuebar from the LSND experiment is compared with the negative results of the KARMEN numubar->nuebar search ... More
Latest Results of the KARMEN2 ExperimentAug 02 2000The neutrino experiment KARMEN at the beam stop neutrino source ISIS investigates the oscillation channel numubar->nuebar in the appearance mode by looking for p(nuebar,e+)n reactions. An analysis of data collected from February 1997 through March 2000 ... More
Exchange-correlation effects in magnetic-field-induced superconductivityOct 01 2001Motivated by recent experiments on the organic superconductor $\lambda-(BETS)_2FeCl_4$ we study the Jaccarino-Peter effect (JPE), the earliest example of magnetic-field-induced superconductivity, from the point of view of current-density-functional theory. ... More
Spatial and temporal spectra of noise driven stripe patternsMar 01 2001Spatial and temporal noise power spectra of stripe patterns are investigated, using as a model a Swift-Hohenberg equation with a stochastic term. In particular, the analytical and numerical investigations show: 1) the temporal noise spectra are of 1/f^alpha ... More
Beam-Beam Effects in the SPS Proton-Anti Proton ColliderOct 13 2014During the proton-anti proton collider run several experiments were carried out in order to understand the effect of the beam-beam interaction on backgrounds and lifetimes. In this talk a selection of these experiments will be presented. From these experiments, ... More
Topics in Quantum Measurement and Quantum NoiseOct 05 1998Oct 06 1998In this thesis we consider primarily the dynamics of quantum systems subjected to continuous observation. In the Schr\"{o}dinger picture the evolution of a continuously monitored quantum system, referred to as a `quantum trajectory', may be described ... More
Full counting statistics for noninteracting fermions: Exact results and the Levitov-Lesovik formulaJan 25 2007May 02 2007Exact numerical results for the full counting statistics (FCS) for a one-dimensional tight-binding model of noninteracting electrons are presented without using an idealized measuring device. The two initially separate subsystems are connected at t=0 ... More
Newton's law for Bloch electrons, Klein factors and deviations from canonical commutation relationsApr 19 2001The acceleration theorem for Bloch electrons in a homogenous external field is usually presented using quasiclassical arguments. In quantum mechanical versions the Heisenberg equations of motion for an operator $\hat {\vec k}(t)$ are presented mostly ... More
On the Interaction of Extreme-Low-Frequency Radiation with Living Matter's Coherent Spiral StatesJan 05 1996Conventional physics cannot explain bioeffects caused by ELF fields [1]. A (double) resonance interaction of ELF radiation with the highly sub-thermal coherent motion of spiral waves in living matter (LM) is suggested. The (geo)magnetic cyclotron resonance ... More
The Cloud-in-Cloud Problem in the Press-Schechter Formalism of Hierarchical Structure FormationAug 24 1994The formalism by Press and Schechter (PS) is often used to infer number densities of virialized objects of mass M (e.g. quasars, galaxies, clusters of galaxies, etc.) from a count of initially overdense regions in a Gaussian density perturbation field. ... More
Barnes-Evans relations for dwarfs with an application to the determination of distances to cataclysmic variablesOct 19 2006Barnes-Evans type relations provide an empirical relationship between the surface brightness of stars and their color. They are widely used for measuring the distances to stars of known radii, as the Roche-lobe filling secondaries in cataclysmic variables ... More
Models of the Accretion Spots in Magnetic Cataclysmic VariablesFeb 12 2003The structure of the near-polar accretion spots on accreting magnetic white dwarfs has been studied theoretically and observationally in numerous papers over the last decade. Detailed treatments are available for the regime of low mass flux, usually termed ... More
Gamma-Ray Emissions from Pulsars: Spectra of the TEV Fluxes from Outer-Gap AcceleratorsMay 22 2000Jun 22 2000We study the gamma-ray emissions from an outer-magnetospheric potential gap around a rotating neutron star. Migratory electrons and positrons are accelerated by the electric field in the gap to radiate copious gamma-rays via curvature process. Some of ... More
CP Results from BelleJan 19 2001The Belle detector at KEKB has collected 6.2 fb^{-1} of data at the Upsilon(4S) resonance. Presented here are preliminary measurements, from this data sample, of sin(2phi_1) and other quantities relating to CP.
Tests of QED with Multi-Photonic Final StatesApr 30 2001In the Standard Model the process e+e- -> gamma-gamma is fully described by QED. Measurements of the differential cross-sections from the four LEP experiments are compared to the QED expectation and limits are set on parameters describing physics beyond ... More
On Self Sustained Photonic GlobesMar 14 2013In this paper we consider a classical treatment of a very dense collection of photons forming a self-sustained globe under its own gravitational influence. We call this a "photonic globe" We show that such a dense photonic globe will have a radius closely ... More
On charm scalar resonancesDec 22 2005A brief overview of charm scalar resonances is given. It is demonstrated that experimental data on the D_s^{*+}gamma and D_s^+pi^0 decays of D_{s0}^+(2317) favor its assignment to the I_3=0 component of iso-triplet four-quark mesons. The broad bump just ... More
BABAR resonance as a new window of hadron physicsMay 20 2003May 21 2003Possible decays of four-quark mesons are studied by assigning the newly observed BABAR resonance to a four-quark meson with C=S=I=1. It is expected that some of them can be observed as narrow resonances. Implication of existence of four-quark mesons in ... More
Relations between classical phase-space distributions and Wigner function for multiparticle production processesMay 21 2007The effects of interpreting classical phase space distributions as Wigner functions, which is common in models of multiparticle production, are discussed. The temperature for the classical description is always higher than that for its Wigner function ... More
Invariance group important for the interpretation of Bose-Einstein correlationsOct 18 2005A group of transformations changing the phases of the elements of the single-particle density matrix, but leaving unchanged the predictions for identical particles concerning the momentum distributions, momentum correlations etc., is identified. Its implications ... More
Inferences from Bose-Einstein correlations in multiple particle production processesOct 14 2003Data on Bose-Einstein correlations yield information about the interaction regions in multiple particle production processes. The conclusions are model dependent. Several popular models are briefly presented, compared and discussed.
The Dirichlet Series for the Liouville Function and the Riemann HypothesisSep 11 2016Sep 23 2016This paper investigates the analytic properties of the Liouville function's Dirichlet series that obtains from the function F(s)= zeta(2s)/zeta(s), where s is a complex variable and zeta(s) is the Riemann zeta function. The paper employs a novel method ... More
QCD phase transition with two flavors of Wilson quarks using a RG improved actionOct 23 1995The finite temperature QCD phase transition is studied on the lattice with degenerate two flavors of Wilson quarks. Motivated by reported strange behaviors with the standard action on lattices with the temporal extention $N_t=4$ and 6, a renormalization ... More
An Introduction to Finite Temperature Quantum Chromodynamics on the LatticeApr 06 1998In these lectures, we introduce finite temperature QCD on the lattice to non-experts of the subject. We first formulate lattice QCD both at zero and finite temperatures. Then a section is devoted to the topic of improved lattice actions which are becoming ... More
The Non-Trivial Phase of $φ^{4}$-Theory in an External Magnetic Field and at Finite TemperatureOct 18 1993The effective potential for the order parameter $\phi ^{\dagger } \phi$ is investigated in massless $\phi ^{4}$-theory in the presence of magnetic fields at finite temperature. It is found that the first order nature of the phase transition from the non-trivial ... More
Heavy Antiquark Pentaquarks in the CM and GB ModelsDec 22 2004The splittings between positive parity pentaquarks containing a single heavy (c,b) antiquark and four light (u,d) quarks are investigated in models having spin-dependent interactions generated by either effective Goldstone boson exchange or effective ... More
Constraints on Hadronic Spectral Functions From Continuous Families of Finite Energy Sum RulesJan 07 1999Hadronic tau decay data is used to study the reliability of various finite energy sum rules (FESR's). For intermediate scales (of order 2-3 GeV^2), those FESR's with weights s^k are found to have significant errors, whereas those with weights having a ... More
Testing Gravity with MuoniumFeb 16 2007Recently a new technique for the production of muon ($\mu^+$) and muonium ($\mu^+e^-$) beams of unprecedented brightness has been proposed. As one consequence and using a highly stable Mach-Zehnder type interferometer, a measurement of the gravitational ... More
On angular ordering in medium-induced radiationFeb 12 2011Medium-induced gluon radiation gives rise to the strong energy-loss observed in single-hadron spectra in heavy-ion collisions. Its angular structure, leading e.g. to intra-jet correlations, is only known for the one-gluon inclusive case. In the vacuum, ... More
Finite T Electroweak Phase Transition on the LatticeAug 14 1996This talk reviews recent lattice results on the high $T$ electroweak phase transition. A remarkably accurate picture emerges: a) the transition is of first order for $m_H \lsim 80$GeV and vanishes for larger $m_H$; b) transition temperature, latent heat ... More
Local Non-Fermi Liquid Theory of Magnetic Impurity Effects in Carbon NanotubesOct 05 1999Magnetic impurity effects in carbon nanotubes are studied theoretically. The multi channel Kondo effect is investigated with the band structure of the metallic nanotubes. The local non-Fermi liquid behavior is realized at temperatures lower than the Kondo ... More
Prevalence of compact nuclear starbursts in nearby Seyfert galaxiesAug 19 2005We present an imaging survey of the CO(1--0), HCN(1--0), and HCO$^+$(1--0) lines in the nearby Seyfert galaxies using the Nobeyama Millimeter Array and RAINBOW Interferometer. Some of the observed Seyfert galaxies including NGC 1068, NGC 1097, NGC 5033, ... More
Recent results on saturation and CGCNov 03 2005I discuss recent results on the Color Glass Condensate which is a dense saturated gluonic state and appears as the universal picture of hadrons or nuclei at very high energies.
The extinction properties of long GRB host galaxies from H and He I recombination linesJan 04 2011In this paper we show how a self-consistent treatment of hydrogen and helium emission line fluxes of the hosts of long gamma-ray bursts can result in improved understanding of the dust properties in these galaxies. In particular, we find that even with ... More
Neutrinoless double beta decayJan 23 2012The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations are presented as well as the current status of experiments. Finally an outlook towards the future, work on nuclear matrix elements and alternative ... More
Experimental neutrino physicsFeb 23 2005The current experimental status of neutrino physics is reviewed. It contains the evidences for a non-vanishing neutrino rest mass from neutrino oscillation searches. In addition an outlook is given on determining the various mixing matrix elements and ... More
Real-time spectroscopy of solar pp neutrinos using Nd-150Aug 11 2011The potential real-time spectroscopy of solar pp neutrinos using Nd-150 as target is investigated. The threshold of 196 keV would be the lowest of all solar neutrino experiments running so far. Experimental rates and parameters are discussed, about 580 ... More
Non-accelerator neutrino mass searchesFeb 14 2000The current status of non-accelerator based searches for effects of a non-vanishing neutrino mass is reviewed. Beside the direct kinematical methods this includes searches for magnetic moments and a discussion of the solar neutrino problem. Double beta ... More
On the physics of massive neutrinosNov 06 1998Massive neutrinos open up the possibility for a variety of new physical phenomena. Among them are oscillations and double beta decay. Furthermore they influence several fields from particle physics to cosmology. In this article the concept of massive ... More
MeV neutrinos in double beta decayMay 26 1996The effect of Majorana neutrinos in the MeV mass range on the double beta decay of various isotopes is studied on pure phenomenological arguments. By using only experimental half life data, limits on the mixing parameter $U_{eh}^2$ of the order 10$^{-7}$ ... More
Status of terrestrial neutrino oscillation searchesJun 16 1997The present status of neutrino oscillation searches with reactors and accelerators is reviewed. An outlook, especially on future long baseline neutrino oscillation projects, is given.
Neutrino oscillations and dark matterDec 17 1996The significance of light massive neutrinos as hot dark matter is outlined. The power of neutrino oscillation experiments with respect to detect such neutrinos in the eV-region is discussed. Present hints for neutrino oscillations in solar, atmospheric ... More
Controlling dynamical entanglement in a Josephson tunneling junctionFeb 02 2016We analyze the evolution of an entangled many-body state in a Josephson tunneling junction. A N00N state, which is a superposition of two complementary Fock states, appears in the evolution with sufficient probability only for a moderate many-body interaction ... More