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Results for "M. Babcock"

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Revisiting the spreading and covering numbersSep 27 2011May 28 2013We revisit the problem of computing the spreading and covering numbers. We show a connection between some of the spreading numbers and the number of non-negative integer 2x2 matrices whose entries sum to d, and we construct an algorithm to compute improved ... More
Structure and Dynamics of the 13/14 November 2012 Eclipse White-Light CoronaDec 03 2014Continuing our series of observations of the motion and dynamics of the solar corona over the solar-activity cycle, we observed the corona from sites in Queensland, Australia, during the 13 (UT)/14 (local time) November 2012 total solar eclipse. The corona ... More
Entanglement of group-II-like atoms with fast measurement for quantum information processingNov 01 2007Dec 03 2008We construct a scheme for the preparation, pairwise entanglement via exchange interaction, manipulation, and measurement of individual group-II-like neutral atoms (Yb, Sr, etc.). Group-II-like atoms proffer important advantages over alkali metals, including ... More
Short-Period Waves That Heat the Corona Detected at the 1999 EclipseFeb 12 2002As a part of a study of the cause of solar coronal heating, we searched for high-frequency (~1 Hz) intensity oscillations in coronal loops in the [Fe XIV] coronal green line. We summarize results from observations made at the 11 August 1999 total solar ... More
Remote sensing to reduce the effects of spatial autocorrelation on design-based inference for forest inventory using systematic samplesOct 19 2018Systematic sampling is often used to select plot locations for forest inventory estimation. However, it is not possible to derive a design-unbiased variance estimator for a systematic sample using one random start. As a result, many forest inventory analysts ... More
Dynamic spatial regression models for space-varying forest stand tablesNov 03 2014Many forest management planning decisions are based on information about the number of trees by species and diameter per unit area. This information is commonly summarized in a stand table, where a stand is defined as a group of forest trees of sufficiently ... More
Demonstration of nonstoquastic Hamiltonian in coupled superconducting flux qubitsMar 14 2019Mar 15 2019Quantum annealing (QA) is a heuristic algorithm for finding low-energy configurations of a system, with applications in optimization, machine learning, and quantum simulation. Up to now, all implementations of QA have been limited to qubits coupled via ... More
Improved Error-Scaling for Adiabatic Quantum State TransferMay 31 2011Sep 15 2011We present a technique that dramatically improves the accuracy of adiabatic state transfer for a broad class of realistic Hamiltonians. For some systems, the total error scaling can be quadratically reduced at a fixed maximum transfer rate. These improvements ... More
Charon's radius and density from the combined data sets of the 2005 July 11 occultationFeb 03 2006The 2005 July 11 C313.2 stellar occultation by Charon was observed by three separate research groups, including our own, at observatories throughout South America. Here, the published timings from the three data sets have been combined to more accurately ... More
Geostatistical estimation of forest biomass in interior Alaska combining Landsat-derived tree cover, sampled airborne lidar and field observationsMay 09 2017Dec 20 2017The goal of this research was to develop and examine the performance of a geostatistical coregionalization modeling approach for combining field inventory measurements, strip samples of airborne lidar and Landsat-based remote sensing data products to ... More
High level of $^3$He polarization of 81\% Maintained in an on-beam $^3$He spin filter using SEOPMar 25 2010Mar 26 2010Maintaining high levels of 3He polarization over long periods of time is important to many areas of fundamental and particle beam physics. Long measurement times are often required in such experiments and the data quality is a function of the 3He polarization. ... More
An ultra compact on-beam 3He polarizer for separation of incoherent background in high Q-range SANSJan 25 2012Incoherent background can create an intrinsic problem for standard small angle neutron scattering measurements. Biological samples contain hydrogen which is a strong incoherent scatterer thus creating an intrinsic source of background that makes determination ... More
Design study of magnetic environments for XYZ polarization analysis using 3He for the new thermal time of flight spectrometer TOPASJan 25 2012We present a finite element calculation of the magnetic field (MagNet software) taken with the newly proposed PASTIS Coil, which uses a wide-angle banana shaped 3He Neuton Spin Filter cell (NSF) to cover a large range of scattering angle. The goal of ... More
The AGI Containment ProblemApr 02 2016Jul 13 2016There is considerable uncertainty about what properties, capabilities and motivations future AGIs will have. In some plausible scenarios, AGIs may pose security risks arising from accidents and defects. In order to mitigate these risks, prudent early ... More
Spatial Factor Models for High-Dimensional and Large Spatial Data: An Application in Forest Variable MappingJan 06 2018Nov 08 2018Gathering information about forest variables is an expensive and arduous activity. As such, directly collecting the data required to produce high-resolution maps over large spatial domains is infeasible. Next generation collection initiatives of remotely ... More
Unambiguous determination of structure parameters for soft matter samples made possible with polarization analysis on JCNS SANS using a 3He spin filterJun 23 2010Incoherent background can create an intrinsic problem for standard small angle neutron scattering measurements. Biological samples contain hydrogen which is a strong incoherent scatterer thus creating an intrinsic source of background that makes determination ... More
Circular Dichroism of RbHe and RbN$_2$ MoleculesJul 30 2010We present measurements of the circular dichroism of optically pumped Rb vapor near the D1 resonance line. Collisions with the buffer gases $^3$He and N$_2$ reduce the transparency of the vapor, even when fully polarized. We use two methods to measure ... More
Breakdown of Angular Momentum Selection Rules in High Pressure Optical Pumping ExperimentsMar 22 2010We present measurements, using two complementary methods, of the breakdown of atomic angular momentum selection rules in He-broadened Rb vapor. Atomic dark states are rendered weakly absorbing due to fine-structure mixing during Rb-He collisions. The ... More
High-precision $Q_{EC}$-value measurement of the superallowed $β^+$ emitter $^{22}$Mg and an evaluation of the $A=22$ isobaric tripletAug 01 2017Nov 06 2017A direct $Q_{EC}$-value measurement of the superallowed $\beta^+$ emitter $^{22}$Mg was performed using TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). The direct ground-state to ground-state atomic mass difference between $^{22}$Mg and $^{22}$Na ... More
Spins and magnetic moments of 58;60;62;64Mn ground states and isomersAug 25 2015The odd-odd 54;56;58;60;62;64Mn isotopes (Z = 25) were studied using bunched-beam collinear laser spectroscopy at ISOLDE, CERN. From the measured hyperfine spectra the spins and magnetic moments of Mn isotopes up to N = 39 were extracted. The previous ... More
Isomer shift and magnetic moment of the long-lived 1/2$^{+}$ isomer in $^{79}_{30}$Zn$_{49}$: signature of shape coexistence near $^{78}$NiApr 12 2016Collinear laser spectroscopy has been performed on the $^{79}_{30}$Zn$_{49}$ isotope at ISOLDE-CERN. The existence of a long-lived isomer with a few hundred milliseconds half-life was confirmed, and the nuclear spins and moments of the ground and isomeric ... More
A new measurement of the permanent electric dipole moment of $^{129}$Xe using $^{3}$He comagnetometry and SQUID detectionFeb 07 2019We describe a new technique to measure the EDM of $^{129}$Xe with $^3$He comagnetometry. Both species are polarized using spin-exchange optical pumping, transferred to a measurement cell, and transported into a magnetically shielded room, where SQUID ... More
Precision mass measurements of $^{125-127}$Cd isotopes and isomers approaching the $N=82$ closed shellMay 12 2017Oct 02 2017We present the results of precision mass measurements of neutron-rich cadmium isotopes. These nuclei approach the $N=82$ closed neutron shell and are important to nuclear structure as they lie near doubly-magic $^{132}$Sn on the chart of nuclides. Of ... More
Neutron Beam Effects on Spin Exchange Polarized He-3Feb 21 2008We have observed depolarization effects when high intensity cold neutron beams are incident on alkali-metal-spin-exchange polarized He-3 cells used as neutron spin filters. This was first observed as a reduction of the maximum attainable He-3 polarization ... More
Electronic anisotropy, magnetic field-temperature phase diagram and their dependence on resistivity in c-axis oriented MgB2 thin filmsApr 28 2001An important predicted, but so far uncharacterized, property of the new superconductor MgB2 is electronic anisotropy arising from its layered crystal structure. Here we report on three c-axis oriented thin films, showing that the upper critical field ... More
Joint hierarchical models for sparsely sampled high-dimensional LiDAR and forest variablesMar 24 2016Dec 05 2016Recent advancements in remote sensing technology, specifically Light Detection and Ranging (LiDAR) sensors, provide the data needed to quantify forest characteristics at a fine spatial resolution over large geographic domains. From an inferential standpoint, ... More
Entangling identical bosons in optical tweezers via exchange interactionDec 15 2007We first devise a scheme to perform a universal entangling gate via controlled collisions between pairs of atomic qubits trapped with optical tweezers. Second, we present a modification to this scheme to allow the preparation of atomic Bell pairs via ... More
Thin Film Magnesium Boride Superconductor with Very High Critical Current Density and Enhanced Irreversibility FieldMar 20 2001The discovery of superconductivity at 39 K in magnesium diboride offers the possibility of a new class of low-cost, high-performance superconducting materials for magnets and electronic applications. With twice the critical temperature of Nb_3Sn and four ... More
Surface residues dynamically organize water bridges to enhance electron transfer between proteinsJun 22 2010Cellular energy production depends on electron transfer (ET) between proteins. In this theoretical study, we investigate the impact of structural and conformational variations on the electronic coupling between the redox proteins methylamine dehydrogenase ... More
A magnetically shielded room with ultra low residual field and gradientMar 25 2014A versatile and portable magnetically shielded room with a field of (700 \pm 200) pT within a central volume of 1m x 1m x 1m and a field gradient less than 300 pT/m is described. This performance represents more than a hundred-fold improvement of the ... More
Mass Measurements of Neutron-Rich Gallium Isotopes Refine Production of Nuclei of the First r-Process Abundance Peak During GW170817Oct 27 2018We report mass measurements of neutron-rich Ga isotopes in the A $\approx$ 84 region crossing the N=50 neutron shell closure with TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). The measurements, employing a multiple-reflection time-of-flight ... More
Dawning of the N=32 shell closure seen through precision mass measurements of neutron-rich titanium isotopesOct 23 2017Jan 18 2018A precision mass investigation of the neutron-rich titanium isotopes $^{51-55}$Ti was performed at TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). The range of the measurements covers the $N=32$ shell closure and the overall uncertainties of ... More
Demonstration of nonstoquastic Hamiltonian in coupled superconducting flux qubitsMar 14 2019Quantum annealing (QA) is a heuristic algorithm for finding low-energy configurations of a system, with applications in optimization, machine learning, and quantum simulation. Up to now, all implementations of QA have been limited to qubits coupled via ... More
Algorithms for Embedding Quantum-Dot Cellular Automata Networks onto a Quantum Annealing ProcessorSep 14 2017Advancements in computing based on qubit networks, and in particular the flux-qubit processor architecture developed by D-Wave System's Inc., have enabled the physical simulation of quantum-dot cellular automata (QCA) networks beyond the limit of classical ... More
Changes in nuclear structure along the Mn isotopic chain studied via charge radiiSep 16 2016The hyperfine spectra of $^{51,53-64}$Mn were measured in two experimental runs using collinear laser spectroscopy at ISOLDE, CERN. Laser spectroscopy was performed on the atomic $3d^5\ 4s^2\ ^{6}\text{S}_{5/2}\rightarrow 3d^5\ 4s4p\ ^{6}\text{P}_{3/2}$ ... More
Spatial Factor Models for High-Dimensional and Large Spatial Data: An Application in Forest Variable MappingJan 06 2018Gathering information about forest variables is an expensive and arduous activity. As such, directly collecting the data required to produce high-resolution maps over large spatial domains is infeasible. Next generation collection initiatives of remotely ... More
Quantum information processing: The case of vanishing interaction energyOct 27 2002We investigate the rate of operation of quantum "black boxes" ("oracles") and point out the possibility of performing an operation by a quantum "oracle" whose average energy equals zero. This counterintuitive result not only presents a generalization ... More
Self-Organized Topological State with Majorana FermionsJul 08 2013Nov 06 2013Topological phases, quite generally, are difficult to come by. They either occur under rather extreme conditions (e.g. the quantum Hall liquids, which require high sample purity, strong magnetic fields and low temperatures) or demand fine tuning of system ... More
Spin Response of Electrons on the Surface of a Topological InsulatorJan 11 2012The surface of a topological insulator hosts a very special form of a quasi-two dimensional metallic system when it is embedded in a topologically trivial medium like the vacuum. The electronic properties of this unusual 2D metal are distinct in many ... More
Massive Neutrino in Non-commutative Space-timeDec 24 2007Apr 01 2008We consider the noncommutative standard model based on $SU(3)\times SU(2)\times U(1)$. We study the gauge transformation of right handed neutrino and its direct interaction with photon in the noncommutative space-time. We show that the massive Dirac neutrinos, ... More
Infinite order excitonic Bloch equations for asymmetric nanostructuresJul 04 2003We present a new exciton-based formalism for calculating the coherent response of asymmetric semiconductor multiple quantum well structures to ultra-short optical pulses valid to infinite order in the optical field and including the self-generated intraband ... More
Scalar StoponiumAug 18 1993We study the decays of a scalar \stst\ bound state \sigst, where \st\ is the lighter stop eigenstate. If \st\ has no tree--level 2--body decays, the dominant decay modes of \sigst\ are $gg$ or, if $m_h < \mst \ll \mstt$, a pair of light scalar Higgs bosons ... More
Photon Neutrino Scattering in Non-Commutative SpaceNov 04 2005Jan 19 2006We extend the non-commutative standard model based on the minimal $SU(3)\times SU(2)\times U(1)$ gauge group to include the interaction of photon with neutrino. We show that, in the gauge invariant manner, only the right handed neutrino can directly couple ... More
Production and Decay of Scalar Stoponium Bound StatesDec 02 1993In this paper we discuss possible signatures for the production of scalar \stst\ (stoponium) bound states \sigst\ at hadron colliders, where \st\ is the lighter scalar top eigenstate. We first study the decay of \sigst; explicit expressions are given ... More
Parton Model in Lorentz Invariant Non-Commutative SpaceMay 26 2004Aug 22 2004We consider the Lorentz invariant non-commutative QED and complete the Feynman rules for the theory up to the order $\theta^2$. In the Lorentz invariant version of the non-commutative QED the particles with fractional charges can be also considered. We ... More
Electromagnetic Response of Weyl SemimetalsMar 22 2013Jun 27 2013It has been suggested recently, based on subtle field-theoretical considerations, that the electromagnetic response of Weyl semimetals and the closely related Weyl insulators can be characterized by an axion term E.B with space and time dependent axion ... More
The Charm Quark Contribution to the Proton Structure FunctionOct 14 2006Dec 27 2006The charm quark structure function $F^c_2$ and the longitudinal structure function $F_l^p$ are directly sensitive to the gluon content of proton and therefore are crucial in understanding of proton structure function, in particular at low momentum transfer ... More
The decay of singlet scalar dark matter to unparticle and photonMay 06 2008We consider the unparticle physics introduced by Georgi and show that if the standard model is extended to include a singlet scalar as a dark matter candidate, there is a channel which leads to its decay to photon and unparticle. We calculate the decay ... More
An Estimate of Referent of Noun Phrases in Japanese SentencesDec 13 1999In machine translation and man-machine dialogue, it is important to clarify referents of noun phrases. We present a method for determining the referents of noun phrases in Japanese sentences by using the referential properties, modifiers, and possessors ... More
On the canonically invariant calculation of Maslov indicesMay 30 2003Jun 18 2003After a short review of various ways to calculate the Maslov index appearing in semiclassical Gutzwiller type trace formulae, we discuss a coordinate-independent and canonically invariant formulation recently proposed by A Sugita (2000, 2001). We give ... More
Viscosity in cosmological simulations of clusters of galaxiesDec 06 2005The physics of the intracluster medium, in particular the values for the thermal conductivity and the viscosity are largely unknown and subject to an ongoing debate. Here, we study the effect of viscosity on the thermal state of the intracluster medium ... More
Evolution of the Internal Dynamics of Galaxy ClustersOct 16 2000We consider a sample of 51 distant galaxy clusters at 0.15<z<0.9 (<z> about 0.3), each cluster having at least 10 galaxies with available redshift in the literature. We select member galaxies, analyze the velocity dispersion profiles, and evaluate in ... More
Higher-order QCD corrections to supersymmetric particle production and decay at the LHCJan 27 2015Feb 23 2015We review recent results on higher-order calculations to squark and gluino production and decay at the LHC, as obtained within the Collaborative Research Centre / Transregio 9 "Computational Particle Physics". In particular, we discuss inclusive cross ... More
Two-loop mixing of dimension-five flavor-changing operatorsSep 30 1994Oct 17 1994We calculate the two-loop QCD mixing of the dimension-five flavor-changing operators that arise in the Standard Model after integrating out the $W$, $Z$ and Higgs bosons and the top-quark, i.e.~the mixing among gluonic and photonic magnetic moment operators. ... More
The Vector Meson Mass in Chiral Effective Field TheoryMay 01 2014A brief overview of Quantum Chromodynamics (QCD) as a non-Abelian gauge field theory, including symmetries and formalism of interest, will precede a focused discussion on the use of an Effective Field Theory (EFT) as a low energy perturbative expansion ... More
How much can supergravity teach us about microscopic features of BPS black holes?Dec 20 2000We review recent results in the study of regular four dimensional BPS black holes in toroidally compactified type II (or M) theory. We discuss the generating solution for this kind of black holes, its microscopic description(s), and compute the corresponding ... More
Regular BPS black holes: macroscopic and microscopic description of the generating solutionFeb 23 2000Jun 06 2000In this paper we construct the BPS black hole generating solution of toroidally compactified string (and M) theory, giving for it both the macroscopic and microscopic description. Choosing a proper U-duality gauge the latter will be given by a bound state ... More
Comment on ``A Comparison Between Broad Histogram and Multicanonical Methods''Nov 30 2000Jan 08 2001A recent paper by A. R. Lima, P. M. C. de Oliveira, and T. J. P. Penna [cond-mat/0002176; J. Stat. Phys. 99:691 (2000)], seems to contain at least two mistakes which deserve comment, one concerning the numerical data, the other being of a conceptual kind. ... More
Beyond mean field: On the role of pair excitations in the evolution of condensatesSep 24 2015This paper (published in 2013) introduces a refinement of the equations for the pair excitation function used in our previous work with D. Margetis. The new equations are Euler-Lagrange equations, and the solutions conserve energy and the number of particles. ... More
QCD Coupling Constant at Finite TemperatureMay 02 1996We work out the method for evaluating the QCD coupling constant at finite temperature ($T$) by making use of the finite $T$ renormalization group equation up to the one-loop order on the basis of the background field method with the imaginary time formalism. ... More
Direct evidence for a characteristic dynamic lengthscale in the intermediate phase of glassesJul 23 2010AC conductivity spectra of xAgI-(1-x)AgPO$_3$ fast ion conducting glasses spanning the flexible, intermediate (isostatically rigid) and stressed rigid phases are analyzed. The rescaled frequency dependent spectra are mapped into time-dependent mean square ... More
Andreev reflection at QGP/CFL interfaceJan 23 2002Apr 12 2002In this letter we address the question of the phenomena of Andreev reflection between the cold quark-gluon plasma phase and CFL color superconductor. We show that there are two different types of reflections connected to the structure of the CFL phase. ... More
Multi-particle correlations of an oscillating scattererNov 16 2005Using multi-particle distribution functions we calculate the correlations produced by a periodically driven scatterer in a system of noninteracting electrons at zero temperature. The multi-particle correlations due to a quantum exchange effect are expressed ... More
Quantum pumping: Coherent Rings versus Open ConductorsJul 28 2003We examine adiabatic quantum pumping generated by an oscillating scatterer embedded in a one-dimensional ballistic ring and compare it with pumping caused by the same scatterer connected to external reservoirs. The pumped current for an open conductor, ... More
The helium abundances in HgMn and normal starsJul 26 2004The parameter-free model of diffusion in the atmospheres of HgMn stars (Michaud 1986; Michaud et al 1979) predicts that helium should sink below the He II ionization zone in order that diffusion of other elements may take place, and that all HgMn stars ... More
The universal effective potential for three-dimensional massive scalar field theory from the Monte Carlo study of the Ising modelJan 29 1994We study the low-energy effective action $S_{eff}[\varphi]$ for the one-component real scalar field theory in three Euclidean dimensions in the symmetric phase, concentrating on its static part --- effective potential $V_{eff}(\varphi)$. It characterizes ... More
Ultra-high Energy Predictions of Proton-Air Cross Sections from Accelerator Data: an UpdateSep 13 2011At $\sqrt s = 57\pm 7$ TeV, the Pierre Auger Observatory (PAO) collaboration has recently measured the proton-air inelastic production cross section $\sigma_{\rm p-air}$. Assuming a helium contamination of 25%, they subtracted 30 mb from their measured ... More
Ultra-high Energy Predictions of proton-air Cross Sections from Accelerator DataMay 21 2007We predict $\sigma_{p{-}\rm air}^{\rm prod}$, the proton--air inelastic production cross section, at $pp$ center-of-mass energies $2\le\sqrt s \le 100000$ TeV, using high energy predictions from a saturated Froissart bound parameterization of accelerator ... More
Exact solutions of Klein Gordon equation for the Makarov potential with the asymptotic iteration methodMar 25 2010We derive exact analytical solutions of the Klein-Gordon equation for Makarov potential by means of the asymptotic iteration method. The energy eigenvalues are given in a closed form and the corresponding normalized eigenfunctions are obtained in terms ... More
Event-by-Event Fluctuations in Particle Multiplicities and Transverse Energy Produced in 158.A GeV Pb+Pb collisionsAug 31 2001Mar 20 2002Event-by-event fluctuations in the multiplicities of charged particles and photons, and the total transverse energy in 158$\cdot A$ GeV Pb+Pb collisions are studied for a wide range of centralities. For narrow centrality bins the multiplicity and transverse ... More
Transverse mass distributions of neutral pions from $^{208}$Pb-induced reactions at 158$\cdot A$ GeVAug 03 2001Dec 20 2001Results on transverse mass spectra of neutral pions measured at central rapidity are presented for impact parameter selected 158$\cdot A$ GeV Pb + Pb, and Pb + Nb collisions. The distributions cover the range $0.5 \mathrm{GeV}/c^{2} \le m_{T} - m_{0} ... More
The clustering properties of the first galaxiesNov 17 2009Jun 01 2010We study the clustering properties of the first galaxies formed in the Universe. We find that, due to chemical enrichment of the inter-stellar medium by isolated Population III stars formed in mini-halos at redshift z>30, the (chronologically) first galaxies ... More
Dust absorption along the line of sight for high-redshift objectsJul 10 2006We estimate the optical depth distribution of dust present in absorption systems along the line of sight of high redshift galaxies and the resulting reddening. We characterize the probability distribution of the transmission to a given redshift and the ... More
Neutral gas density in Damped Lyman Alpha systemsJun 28 2006We estimate the intrinsic neutral gas density in Damped Lyman Alpha systems ($\Omega_{HI}^{(DLA)}$) in the redshift range $ 2.2 \lesssim z \lesssim 5$ from the DLA SDSS DR_3 sample of optically selected quasars. We take into account self-consistently ... More
The very first Pop III stars and their relation to bright z~6 quasarsOct 04 2007We discuss the link between dark matter halos hosting the first PopIII stars formed at redshift z > 40 and the rare, massive, halos that are generally considered to host bright z~6 quasars. We show that within the typical volume occupied by one bright ... More
A New Approach to the Internal Calibration of Reverberation Mapping SpectraSep 13 2016We present a new procedure for the internal (night-to-night) calibration of time series spectra, with specific applications to optical AGN reverberation mapping data. The traditional calibration technique assumes that the narrow [OIII]$\lambda$5007 emission ... More
Two-photon annihilation of singlet cold dark matters due to noncommutative space-timeOct 01 2012Detecting the cosmic rays, in particular gamma-ray, coming from the dark matter annihilation or decay is an indirect way to survey the nature of the dark matter. In the commutative space-time, the annihilation of the dark matter candidates (WIMPs) to ... More
Riemann-Hilbert approach to multi-time processes; the Airy and the Pearcey caseApr 26 2011We prove that matrix Fredholm determinants related to multi-time processes can be expressed in terms of determinants of integrable kernels \`a la Its-Izergin-Korepin-Slavnov (IIKS) and hence related to suitable Riemann-Hilbert problems, thus extending ... More
The transition between the gap probabilities from the Pearcey to the Airy process; a Riemann-Hilbert approachMay 21 2010Mar 31 2011We consider the gap probability for the Pearcey and Airy processes; we set up a Riemann--Hilbert approach (different from the standard one) whereby the asymptotic analysis for large gap/large time of the Pearcey process is shown to factorize into two ... More
Quark Droplets in the NJL Mean FieldJul 20 1998We study the conditions for the existence of stable quark matter in the Nambu--Jona-Lasinio mean field at zero temperature and discuss its interpretation.
Paracontrolled quasilinear SPDEsOct 25 2016We introduce a non-linear paracontrolled calculus and use it to renormalise a class of singular SPDEs including certain quasilinear variants of the periodic two dimensional parabolic Anderson model.
Fractional Supersymmetry as a Superposition of Ordinary SupersymmetrySep 05 2005It is shown how to derive fractional supersymmetric quantum mechanics of order k as a superposition of k-1 copies of ordinary supersymmetric quantum mechanics.
Two-Photon Laser Spectroscopy of Transition Ions in Crystals: Inter- Configurational TransitionsNov 18 1998Symmetry adaptation techniques are applied to the determination of the intensity of two-photon absorption transitions, between Stark levels of configurations with opposite parities, for transition ions in finite symmetry environments. The equivalence ... More
Symmetry Adaptation and Two-Photon Spectroscopy of Ions in Molecular or Solid-State Finite SymmetryNov 18 1998Finite symmetry adaptation techniques are applied to the determination of the intensity strength of two-photon transitions for ions with one partly-filled shell nl in crystalline environments of symmetry G. We treat the case of intra- configurational ... More
Statistical Mechanics of $qp$-Bosons in $D$ DimensionsDec 06 1995Jan 02 1996This paper is concerned with statistical properties of a gas of $qp$-bosons without interaction. Some thermodynamical functions for such a system in $D$ dimensions are derived. Bose-Einstein condensation is discussed in terms of the parameters $q$ and ... More
171Yb+ System Stability, 5D3/2 Hyperfine State Detection Efficiency and F=2 LifetimeOct 09 2013A data acquisition system is described that is designed to stabilize cooling and probe rates to maximize detection sensitivity and minimize possible systematic errors due to correlations between drifting experimental conditions and varying drive parameters. ... More
From the microcosm of the atomic nuclei to the macrocosm of the starsJun 08 2007A necessary condition for the reliable modelling of the structure or evolution of the stars and of their concomitant nucleosynthesis is the availability of good quality nuclear data in a very wide area of the chart of nuclides. This short review presents ... More
Bound States and Instabilities of VorticesMar 28 1995We examine the spectrum of small perturbations around global and local (gauge) abelian vortices, using simple numerical matrix techniques. The results are of interest for both cosmic strings and for their condensed matter analogues, superfluid and superconducting ... More
Coincidence of Universe age in $Λ$CDM and Milne cosmologiesMay 08 2006Nov 09 2006The age of the Universe in the $\Lambda$CDM cosmology with $\Omega_{matter}=0.26$ and $\Omega_{\Lambda}=0.74$ is the same as in the Milne cosmology which correspods to an almost empty universe. In both cases it is a reciprocal Hubble constant, $1/H_0$, ... More
A non-perturbative treatment of the generalized Su-Schreiffer-Heeger Hamiltonian on a dimerOct 11 2000Starting from the Hamiltonian for a dimer which includes all the electronic and electron-phonon terms consistent with a non-degenerate orbital, by a sequence of displacement and squeezing transformation we obtain an effective polaronic Hamiltonian. The ... More
Origin of Blazar ActivityFeb 01 1999Models of Blazars based on the propagation of finite discontinuities or fronts in the Poynting flux jet from the innermost regions of an accretion disk around a black hole are discussed. Such fronts may be responsible for short time-scale (from less than ... More
A Study of Cyg OB2: Pointing the Way Towards Finding Our Galaxy's Super Star ClustersJul 30 2003New optical MK classification spectra have been obtained for 14 OB star candidates identified by Comeron et al. (2002) and presumed to be possible members of the Cyg OB2 cluster. All 14 candidate OB stars observed are indeed early-type stars, strongly ... More
Invariant construction of solutions to Einstein's field equations - LRS perfect fluids IIAug 24 1998The properties of LRS class II perfect fluid space-times are analyzed using the description of geometries in terms of the Riemann tensor and a finite number of its covariant derivatives. In this manner it is straightforward to obtain the plane and hyperbolic ... More
Are Simple Real Pole Solutions Physical?Feb 11 2000We consider exact solutions generated by the inverse scattering technique, also known as the soliton transformation. In particular, we study the class of simple real pole solutions. For quite some time, those solutions have been considered interesting ... More
Large $\pt$ Hadroproduction of Heavy QuarksNov 10 1993The production of heavy quarks at large $\pt$ ($\pt\gg m$) in hadronic collisions is considered. The analysis is carried out in the framework of perturbative fragmentation functions, thereby allowing a resummation at the NLO level of final state large ... More
A remark on sphaleron erasure of baryon asymmetryNov 24 1999Jan 20 2000We complete an existing result for how the baryon asymmetry left over after a period of full thermal equilibrium depends on different lepton asymmetries.
An all-order discontinuity at the electroweak phase transitionJul 27 1999Aug 27 1999We define a non-local gauge-invariant Green's function which can distinguish between the symmetric (confinement) and broken (Higgs) phases of the hot SU(2)xU(1) electroweak theory to all orders in the perturbative expansion. It is related to the coupling ... More
Why are dense planetary rings only found between 8 and 20 AU?Feb 26 2015Mar 13 2015The recent discovery of dense rings around the Centaur Chariklo (and possibly Chiron) reveals that complete dense planetary rings are not only found around Saturn and Uranus, but also around small bodies orbiting in the vicinity of those giant planets. ... More
The global properties of all variety of AGNDec 13 2004Active Galactic Nuclei (AGN) have been a challenging field of research for the past six decades. Nevertheless, many questions still remain unanswered today, regardless of the tremendous theoretical and technological advances. In this brief review I propose ... More
Insights into the High Temperature Superconducting Cuprates from Resonant Inelastic X-ray ScatteringFeb 21 2014Apr 04 2014Recent improvements in instrumentation have established resonant inelastic x-ray scattering (RIXS) as a valuable new probe of the magnetic excitations in the cuprates. This article introduces RIXS, focusing on the Cu $L_3$ resonance, and reviews recent ... More