Results for "Thomas M. Fischer"

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Excluded volume causes integer and fractional plateaus in colloidal ratchet currentsJul 06 2015We study the collective transport of paramagnetic colloids driven above a magnetic bubble lattice by an external rotating magnetic field. We measure a direct ratchet current which rises in integer and fractional steps with the field amplitude. The stepwise ... More
Duality for SudokuJan 04 2013We consider a mathematical model for the classical Sudoku puzzle, which we call the primal problem and introduce a corresponding dual problem. Both problems are constraint satisfaction models and a duality relation between them is proved. Based on these ... More
Unicity Concepts for SudokuOct 02 2014This paper deals with a generalized Sudoku problem and investigates the unicity of a given solution. We introduce constraint sets, which is a generalization of the rows, columns and blocks of a classical Sudoku puzzle. The unicity property is characterized ... More
A Necessary Solution Condition for SudokuOct 23 2012We develop a new discrete mathematical model which includes the classical Sudoku puzzle, Latin Squares and gerechte designs. This problem is described by integer equations and a special type of inequality constraint. We consider solutions of this generalized ... More
Macroscopic Floquet topological crystalline steel pumpJul 17 2017The transport of a steel sphere on top of two dimensional periodic magnetic patterns is studied experimentally. Transport of the sphere is achieved by moving an external permanent magnet on a closed loop around the two dimensional crystal. The transport ... More
Fast and rewritable colloidal assembly via field synchronized particle swappingJul 07 2015We report a technique to realize reconfigurable colloidal crystals by using the controlled motion of particle defects above an externally modulated magnetic substrate. The transport of particles is induced by applying a uniform rotating magnetic field ... More
Vector interaction enhanced bag model for astrophysical applicationsMar 25 2015For quark matter studies in astrophysics the thermodynamic bag model (tdBAG) has been widely used. Despite its success it fails to account for various phenomena expected from Quantum-Chromo-Dynamics (QCD). We suggest a straightforward extension of tdBAG ... More
Dynamical gap generation in graphene with frequency dependent renormalization effectsMay 05 2016We study the frequency dependencies in the renormalization of the fermion Greens function for the $\pi$-band electrons in graphene and their influence on the dynamical gap generation at sufficiently strong interaction. Adopting the effective QED-like ... More
Blood crystal: emergent order of red blood cells under wall-confined shear flowNov 23 2017Driven or active suspensions can display fascinating collective behavior, where coherent motions or structures arise on a scale much larger than that of the constituent particles. Here, we report experiments and numerical simulations revealing that red ... More
The role of frequency dependence in dynamical gap generation in grapheneNov 03 2017Mar 08 2018We study the frequency dependencies of the fermion and photon dressing functions in dynamical gap generation in graphene. We use a low energy effective QED-like description, but within this approximation, we include all frequency dependent effects including ... More
Hard topological versus soft geometrical magnetic particle transportJul 10 2019The transport on top of a periodic two-dimensional hexagonal magnetic pattern of (i) a single macroscopic steel sphere, (ii) a doublet of wax/magnetite composite spheres, and (iii) an immiscible mixture of ferrofluid droplets with a perfluorinated liquid ... More
Topological protection of multiparticle dissipative transportJun 14 2016Topological protection allows robust transport of localized phenomena such as quantum information, solitons, and dislocations. The transport can be either dissipative or non-dissipative. Here, we experimentally demonstrate and theoretically explain the ... More
Topologically protected colloidal transport above a square magnetic latticeAug 02 2016We theoretically study the motion of magnetic colloidal particles above a magnetic pattern and compare the predictions with Brownian dynamics simulations. The pattern consists of alternating square domains of positive and negative magnetization. The colloidal ... More
Topologically protected colloidal transport above a square magnetic latticeAug 02 2016Oct 31 2016We theoretically study the motion of magnetic colloidal particles above a magnetic pattern and compare the predictions with Brownian dynamics simulations. The pattern consists of alternating square domains of positive and negative magnetization. The colloidal ... More
Quantifying the uncertainty of variance partitioning estimates of ecological datasetsDec 01 2018Jan 31 2019An important objective of experimental biology is the quantification of the relationship between predictor and response variables, a statistical analysis often termed variance partitioning (VP). In this paper, a series of simulations is presented, aiming ... More
Influence of voltmeter input impedance on quantum Hall effect measurementsNov 19 2004Dec 08 2004We report on the influence of voltmeters on measurements of the longitudinal resistance in the quantum Hall effect regime. We show that for typical input resistances for standard digital lock-in amplifiers the longitudinal resistance can show a non-zero ... More
Measuring carrier density in parallel conduction layers of quantum Hall systemsNov 19 2004An experimental analysis for two parallel conducting layers determines the full resistivity tensor of the parallel layer, at magnetic fields where the other layer is in the quantum Hall regime. In heterostructures which exhibit parallel conduction in ... More
Characterizing the Youngest Herschel-detected Protostars I. Envelope Structure Revealed by CARMA Dust Continuum ObservationsNov 04 2014We present CARMA 2.9 mm dust continuum emission observations of a sample of 14 Herschel-detected Class 0 protostars in the Orion A and B molecular clouds, drawn from the PACS Bright Red Sources (PBRS) sample (Stutz et al.). These objects are characterized ... More
Hydrodynamic attraction and repulsion between asymmetric rotorsFeb 17 2010At low Reynolds numbers, the hydrodynamic interaction between dumbbells driven by an external rotating field can be attractive or repulsive. Dumbbells of dissimilar asymmetric shape or different coupling to the external field undergo conformational rearrangements ... More
On Conditioning GANs to Hierarchical OntologiesMay 16 2019The recent success of Generative Adversarial Networks (GAN) is a result of their ability to generate high quality images from a latent vector space. An important application is the generation of images from a text description, where the text description ... More
Aggregation and sedimentation of active Brownian particles at constant affinityNov 14 2018We study the motility-induced phase separation of active particles driven through the interconversion of two chemical species controlled by ideal reservoirs (chemiostats). As a consequence, the propulsion speed is non-constant and depends on the actual ... More
Consequences of simultaneous chiral symmetry breaking and deconfinement for the isospin symmetric phase diagramAug 15 2016The thermodynamic bag model (tdBag) has been applied widely to model quark matter properties in both heavy-ion and astrophysics communities. Several fundamental physics aspects are missing in tdBag, e.g., dynamical chiral symmetry breaking (D$\chi$SB) ... More
A mechanical erosion model for two-phase mass flowsOct 06 2016Erosion, entrainment and deposition are complex and dominant, but yet poorly understood, mechanical processes in geophysical mass flows. Here, we propose a novel, process-based, two-phase, erosion-deposition model capable of adequately describing these ... More
Optical Characterization of Single Mode Components by new Medianfield-methodJun 10 2007In this paper a new method for spotsize-measurement for singlemode optical components is presented. Based from the classical farfield-method where the measurements are made circular, the mounting of the used rotary stages and the long measurement time ... More
Simultaneous chiral symmetry restoration and deconfinement - Consequences for the QCD phase diagramMar 11 2016For studies of quark matter in astrophysical scenarios the thermodynamic bag model (tdBag) is commonly employed. Although successful, it does not account for dynamical chiral symmetry breaking (D$\chi$SB) and repulsions due to the vector interaction which ... More
U-Net: Convolutional Networks for Biomedical Image SegmentationMay 18 2015There is large consent that successful training of deep networks requires many thousand annotated training samples. In this paper, we present a network and training strategy that relies on the strong use of data augmentation to use the available annotated ... More
Descriptor Matching with Convolutional Neural Networks: a Comparison to SIFTMay 22 2014Jun 24 2015Latest results indicate that features learned via convolutional neural networks outperform previous descriptors on classification tasks by a large margin. It has been shown that these networks still work well when they are applied to datasets or recognition ... More
A mechanical model for phase-separation in debris flowOct 12 2016Understanding the physics of phase-separation between solid and fluid phases as a mixture mass moves down slope is a long-standing challenge. Here, we propose an extension of the two phase mass flow model (Pudasaini, 2012) by including a new mechanism, ... More
Bit Rate of ProgramsAug 22 2013A program can be considered as a device that generates discrete time signals, where a signal is an execution. Shannon information rate, or bit rate, of the signals may not be uniformly distributed. When the program is specified by a finite state transition ... More
Uniformly Rotating Rings in General RelativityJun 21 2005Sep 02 2005In this paper, we discuss general relativistic, self-gravitating and uniformly rotating perfect fluid bodies with a toroidal topology (without central object). For the equations of state describing the fluid matter we consider polytropic as well as completely ... More
The streaming rollout of deep networks - towards fully model-parallel executionJun 13 2018Nov 02 2018Deep neural networks, and in particular recurrent networks, are promising candidates to control autonomous agents that interact in real-time with the physical world. However, this requires a seamless integration of temporal features into the network's ... More
Dimensional crossover in Sr$_2$RuO$_4$ within slave-boson mean-field theoryDec 19 2008Motivated by the anomalous temperature dependence of the c-axis resistivity of Sr$_2$RuO$_4$, the dimensional crossover from a network of perpendicular one-dimensional chains to a two-dimensional system due to a weak hybridization between the perpendicular ... More
Hybrid metal-dielectric nanocavity for enhanced light-matter interactionsJun 27 2014Jan 13 2017Despite tremendous advances in the fundamentals and applications of cavity quantum electrodynamics (CQED), investigations in this field have primarily been limited to optical cavities composed of purely dielectric materials. Here, we demonstrate a hybrid ... More
A Light-Matter Interface based on a Single InAs/GaAs Quantum Dot in a Nanometallic CavityJun 27 2014Apr 24 2015Despite tremendous advances in the fundamentals and applications of cavity quantum electrodynamics with single InAs/GaAs quantum dots, investigations in this field have been limited to optical cavities composed of purely dielectric materials. Here, we ... More
Characterizing the Youngest Herschel-detected Protostars II. Molecular Outflows from the Millimeter and the Far-infraredJul 04 2016We present CARMA CO (J=1-0) observations and Herschel PACS spectroscopy, characterizing the outflow properties toward extremely young and deeply embedded protostars in the Orion molecular clouds. The sample comprises a subset of the Orion protostars known ... More
Gut microbiome composition: back to baseline?Jun 27 2019In Nature Microbiology, Palleja and colleagues studied the changes in gut microbiome composition in twelve healthy men over a period of six months following an antibiotic intervention. The authors argued that the 'gut microbiota of the subjects recovered ... More
A Herschel and APEX Census of the Reddest Sources in Orion: Searching for the Youngest ProtostarsFeb 05 2013We perform a census of the reddest, and potentially youngest, protostars in the Orion molecular clouds using data obtained with the PACS instrument onboard the Herschel Space Observatory and the LABOCA and SABOCA instruments on APEX as part of the Herschel ... More
Results from HOPS: A Multiwavelength Census of Orion ProtostarsDec 05 2012Surveys with the Spitzer and Herschel space observatories are now enabling the discovery and characterization of large samples of protostars in nearby molecular clouds, providing the observational basis for a detailed understanding of star formation in ... More
Pre-conceptual Design Assessment of DEMO Remote MaintenanceSep 27 2013EDFA, as part of the Power Plant Physics and Technology programme, has been working on the pre-conceptual design of a Demonstration Power Plant (DEMO). As part of this programme, a review of the remote maintenance strategy considered maintenance solutions ... More
The Herschel Orion Protostar Survey: Luminosity and Envelope EvolutionApr 19 2017The Herschel Orion Protostar Survey obtained well-sampled 1.2 - 870 micron spectral energy distributions (SEDs) of over 300 protostars in the Orion molecular clouds, home to most of the young stellar objects (YSOs) in the nearest 500 pc. We plot the bolometric ... More
Quasi-two-dimensional Fermi gases at finite temperatureAug 03 2014We consider a Fermi gas with short-range attractive interactions that is confined along one direction by a tight harmonic potential. For this quasi-two-dimensional (quasi-2D) Fermi gas, we compute the pressure equation of state, radio frequency spectrum, ... More
BCS-BEC crossover in a quasi-two-dimensional Fermi gasJan 22 2013Mar 01 2014We consider a two-component gas of fermionic atoms confined to a quasi-two-dimensional (quasi-2D) geometry by a harmonic trapping potential in the transverse direction. We construct a mean field theory of the BCS-BEC crossover at zero temperature that ... More
Multiwavelength Observations of V2775 Ori, an Outbursting Protostar in L 1641: Exploring the Edge of the FU Orionis RegimeJul 10 2012Individual outbursting young stars are important laboratories for studying the physics of episodic accretion and the extent to which this phenomenon can explain the luminosity distribution of protostars. We present new and archival data for V2775 Ori ... More
Colloidal topological insulatorsNov 14 2017Topological insulators insulate in the bulk but exhibit robust conducting edge states protected by the topology of the bulk material. Here, we design a colloidal topological insulator and demonstrate experimentally the occurrence of edge states in a classical ... More
Herschel Observations of Protoplanetary Disks in Lynds 1641Jun 18 2018We analyze Herschel Space Observatory observations of 104 young stellar objects with protoplanetary disks in the ~1.5 Myr star-forming region Lynds 1641 (L1641) within the Orion A Molecular Cloud. We present spectral energy distributions from the optical ... More
Edge states at the boundary between topologically equivalent latticesSep 18 2018Edge currents of paramagnetic colloidal particles propagate at the edge between two topologically equivalent magnetic lattices of different lattice constant when the system is driven with periodic modulation loops of an external magnetic field. The number ... More
Adversarial Examples for Semantic Image SegmentationMar 03 2017Machine learning methods in general and Deep Neural Networks in particular have shown to be vulnerable to adversarial perturbations. So far this phenomenon has mainly been studied in the context of whole-image classification. In this contribution, we ... More
Influence of Stellar Multiplicity On Planet Formation. I. Evidence of Suppressed Planet Formation Due to Stellar Companions Within 20 AU and Validation of Four Planets From the Kepler Multiple Planet CandidatesSep 27 2013Jan 04 2014The planet occurrence rate for multiple stars is important in two aspects. First, almost half of stellar systems in the solar neighborhood are multiple systems. Second, the comparison of the planet occurrence rate for multiple stars to that for single ... More
Vector-Interaction-Enhanced Bag ModelFeb 09 2018A commonly applied quark matter model in astrophysics is the thermodynamic bag model (tdBAG). The original MIT bag model approximates the effect of quark confinement, but does not explicitly account for the breaking of chiral symmetry, an important property ... More
Universal Adversarial Perturbations Against Semantic Image SegmentationApr 19 2017Jul 31 2017While deep learning is remarkably successful on perceptual tasks, it was also shown to be vulnerable to adversarial perturbations of the input. These perturbations denote noise added to the input that was generated specifically to fool the system while ... More
STDP as presynaptic activity times rate of change of postsynaptic activitySep 19 2015Mar 21 2016We introduce a weight update formula that is expressed only in terms of firing rates and their derivatives and that results in changes consistent with those associated with spike-timing dependent plasticity (STDP) rules and biological observations, even ... More
HOPS 383: An Outbursting Class 0 Protostar in OrionJan 02 2015Jan 06 2015We report the dramatic mid-infrared brightening between 2004 and 2006 of HOPS 383, a deeply embedded protostar adjacent to NGC 1977 in Orion. By 2008, the source became a factor of 35 brighter at 24 microns with a brightness increase also apparent at ... More
Rigorous results on Schroedinger operators with certain Gaussian random potentials in multi-dimensional continuous spaceApr 30 1997Schroedinger operators with certain Gaussian random potentials in multi-dimensional Euclidean space possess almost surely an absolutely continuous integrated density of states and no absolutely continuous spectrum at sufficiently low energies.
Constraining the Rate of Protostellar Accretion Outbursts in the Orion Molecular CloudsJan 23 2019Outbursts due to dramatic increases in the mass accretion rate are the most extreme type of variability in young stellar objects. We searched for outbursts among 319 protostars in the Orion molecular clouds by comparing 3.6, 4.5, and 24 micron photometry ... More
C/O and Mg/Si Ratios of Stars in the Solar NeighborhoodAug 22 2016The carbon to oxygen ratio in a protoplanetary disk can have a dramatic influence on the compositions of any terrestrial planets formed. In regions of high C/O, planets form primarily from carbonates and in regions of low C/O, the ratio of magnesium to ... More
$T$-odd correlations in polarized top quark decays in the sequential decay $t(\uparrow) \to X_b+W^+(\to \ell^+ + ν_\ell)$ and in the quasi three-body decay $t(\uparrow) \to X_b+ \ell^+ + ν_\ell$Feb 07 2018We identify the $T$-odd structure functions that appear in the description of polarized top quark decays in the sequential decay $t(\uparrow) \to X_b+W^+(\to \ell^+ + \nu_\ell)$ (two structure functions) and the quasi three-body decay $t(\uparrow) \to ... More
Finite volume effects in a quenched lattice-QCD quark propagatorDec 19 2005Mar 18 2006We investigate finite volume effects in the pattern of chiral symmetry breaking. To this end we employ a formulation of the Schwinger-Dyson equations on a torus which reproduces results from the corresponding lattice simulations of staggered quarks and ... More
Comparing PyMorph and SDSS photometry. I. Background sky and model fitting effectsFeb 27 2017A number of recent estimates of the total luminosities of galaxies in the SDSS are significantly larger than those reported by the SDSS pipeline. This is because of a combination of three effects: one is simply a matter of defining the scale out to which ... More
Coexisting stochastic and coherence resonance in a mean-field dynamo model for Earth's magnetic field reversalsSep 25 2007Using a spherical symmetric mean field alpha^2-dynamo model for Earth's magnetic field reversals, we show the coexistence of the noise-induced phenomena coherence resonance and stochastic resonance. Stochastic resonance has been recently invoked to explain ... More
The isotropic diffusion source approximation for supernova neutrino transportNov 19 2007Jan 21 2009Astrophysical observations originate from matter that interacts with radiation or transported particles. We develop a pragmatic approximation in order to enable multi-dimensional simulations with basic spectral radiative transfer when the computational ... More
$T$-odd correlations in polarized top quark decays in the sequential decay $t(\uparrow) \to X_b+W^+(\to \ell^+ + ν_\ell)$ and in the quasi three-body decay $t(\uparrow) \to X_b+ \ell^+ + ν_\ell$Feb 07 2018May 03 2018We identify the $T$-odd structure functions that appear in the description of polarized top quark decays in the sequential decay $t(\uparrow) \to X_b+W^+(\to \ell^+ + \nu_\ell)$ (two structure functions) and the quasi-three-body decay $t(\uparrow) \to ... More
A Lattice Gauge Model of Singular Marsden-Weinstein Reduction. Part I. KinematicsJun 15 2006The simplest nontrivial toy model of a classical SU(3) lattice gauge theory is studied in the Hamiltonian approach. By means of singular symplectic reduction, the reduced phase space is constructed. Two equivalent descriptions of this space in terms of ... More
HOPS 136: An Edge-On Orion Protostar Near the End of Envelope InfallDec 20 2013Edge-on protostars are valuable for understanding the disk and envelope properties of embedded young stellar objects, since the disk, envelope, and envelope cavities are all distinctly visible in resolved images and well constrained in modeling. Comparing ... More
Optimisation of sample thickness for THz-TDS measurementsNov 24 2007How thick should the sample be for a transmission THz-TDS measurement? Should the sample be as thick as possible? The answer is `no'. Although more thickness allows T-rays to interact more with bulk material, SNR rolls off with thickness due to signal ... More
Aspects of quark mass generation on a torusJan 16 2007In this talk we report on recent results for the quark propagator on a compact manifold. The corresponding Dyson-Schwinger equations on a torus are solved on volumes similar to the ones used in lattice calculations. The quark-gluon interaction is fixed ... More
Uniqueness of infrared asymptotics in Landau gauge Yang-Mills theorySep 01 2006We uniquely determine the infrared asymptotics of Green functions in Landau gauge Yang-Mills theory. They have to satisfy both, Dyson-Schwinger equations and functional renormalisation group equations. Then, consistency fixes the relation between the ... More
Dynamics of the Young Binary LMC Cluster NGC 1850Oct 20 1992In this paper we have examined the age and internal dynamics of the young binary LMC cluster NGC 1850 using BV CCD images and echelle spectra of 52 supergiants. Isochrone fits to a BV color-magnitude diagram revealed that the primary cluster has an age ... More
The transmission of uncertainty shocks on income inequality: State-level evidence from the United StatesJun 21 2018In this paper, we explore the relationship between state-level household income inequality and macroeconomic uncertainty in the United States. Using a novel large-scale macroeconometric model, we shed light on regional disparities of inequality responses ... More
Uniqueness of infrared asymptotics in Landau gauge Yang-Mills theory IIMar 12 2009We present a shortened and simplified version of our proof \cite{Fischer:2006vf} of the uniqueness of the scaling solution for the infrared asymptotics of Green functions in Landau gauge Yang-Mills theory. The simplification relates to a new RG-invariant ... More
Evolution of Mass Outflow in ProtostarsNov 16 2015We have surveyed 84 Class 0, Class I, and flat-spectrum protostars in mid-infrared [Si II], [Fe II] and [S I] line emission, and 11 of these in far-infrared [O I] emission. We use the results to derive their mass outflow rates. Thereby we observe a strong ... More
Astro2020 Science White Paper: The Formation and Evolution of Multiple Star SystemsApr 17 2019Significant advances have been made over the past decade in the characterization of multiple protostar systems, enabled by the Karl G. Jansky Very Large Array (VLA), high-resolution infrared observations with the Hubble Space Telescope, and ground-based ... More
The Evolution of Protostars: Insights from Ten Years of Infrared Surveys with Spitzer and HerschelJan 08 2014Jan 10 2014Stars form from the gravitational collapse of dense molecular cloud cores. In the protostellar phase, mass accretes from the core onto a protostar, likely through an accretion disk, and it is during this phase that the initial masses of stars and the ... More
Anomalous magnetoresistance peak in (110) GaAs two-dimensional holes: Evidence for Landau-level spin-index anticrossingsSep 12 2005Sep 26 2005We measure an anomalous magnetoresistance peak within the lowest Landau level (nu = 1) minimum of a two-dimensional hole system on (110) GaAs. Self-consistent calculations of the valence band mixing show that the two lowest spin-index Landau levels anticross ... More
Observation of the Quantum Zeno and Anti-Zeno effects in an unstable systemApr 08 2001We report the first observation of the Quantum Zeno and Anti-Zeno effects in an unstable system. Cold sodium atoms are trapped in a far-detuned standing wave of light that is accelerated for a controlled duration. For a large acceleration the atoms can ... More
Complete angular analysis of polarized top decay at O(alpha_s)Jan 29 2001Oct 10 2001We calculate the O(alpha_s) radiative corrections to the three spin independent and five spin dependent structure functions that describe the angular decay distribution in the decay of a polarized top quark into a W-boson (followed by the decay W^{+} ... More
Inclusive Decays of B Mesons into D_s and $D_s^{\ast}$ at $O(α_s)$ Including $D_s^{\ast}$ Polarization EffectsNov 23 1999Apr 06 2000The dominant contribution to the inclusive decays of $B$ mesons into the charm-strangeness mesons $D_s$ and $D_s^{\ast}$ is expected to be given by the partonic process $b \to c+(D_s^-,D_s^{\ast -})$. We determine the nonperturbative $O(1/m_b^2)$ and ... More
Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron ColliderSep 08 2010We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores ... More
Leptonic $ μ$- and $ τ$-decays: mass effects, polarization effects and $ O(α) $ radiative correctionsMar 05 2002Apr 28 2003We calculate the radiative corrections to the unpolarized and the four polarized spectrum and rate functions in the leptonic decay of a polarized $ \mu $ into a polarized electron. The new feature of our calculation is that we keep the mass of the final ... More
Modulating the growth conditions: Si as an acceptor in (110) GaAs for high mobility p-type heterostructuresNov 29 2004We implement metallic layers of Si-doped (110) GaAs as modulation doping in high mobility p-type heterostructures, changing to p-growth conditions for the doping layer alone. The strongly auto-compensated doping is first characterized in bulk samples, ... More
Rayleigh-Benard Convection with a Radial Ramp in Plate SeparationAug 07 2002Pattern formation in Rayleigh-Benard convection in a large-aspect-ratio cylinder with a radial ramp in the plate separation is studied analytically and numerically by performing numerical simulations of the Boussinesq equations. A horizontal mean flow ... More
Outflanking and securely using the PIN/TAN-SystemOct 12 2004May 26 2005The PIN/TAN-system is an authentication and authorization scheme used in e-business. Like other similar schemes it is successfully attacked by criminals. After shortly classifying the various kinds of attacks we accomplish malicious code attacks on real ... More
Longitudinal, transverse-plus and transverse-minus W-bosons in unpolarized top quark decays at O(alpha_s)Nov 06 2000Dec 19 2000We consider the O(alpha_s) radiative corrections to the decay of an unpolarized top quark into a bottom quark and a W-gauge boson where the helicities of the W are specified as longitudinal, transverse-plus and transverse-minus. The O(alpha_s) radiative ... More
Neutrino spectra evolution during proto-neutron star deleptonizationDec 16 2011Dec 19 2011The neutrino-driven wind, which occurs after the onset of a core-collapse supernova explosion, has long been considered as the possible site for the synthesis of heavy r-process elements in the Universe. Only recently, it has been possible to simulate ... More
Accuracy of the Laser Raman system for KATRINMar 19 2012The aim of the Karlsruhe Tritium Neutrino experiment (KATRIN) is the direct (model-independent) measurement of the neutrino mass. For that purpose a windowless gaseous tritium source is used, with a tritium throughput of 40 g/day. In order to reach the ... More
Semi-inclusive decays Lambda_b -> X_c + D_s^* at O(alpha_s) including Lambda_b and D_s^* polarization effectsSep 04 2003Nov 18 2004In the leading order of the (1/m_b)-expansion in HQET the dominant contribution to the semi-inclusive decays of polarized Lambda_b baryons into the charm-strangeness mesons D_s and D_s^* is given by the partonic process b(up) -> c + (D_s^-, D_s^{*-}). ... More
A Spitzer-IRS Detection of Crystalline Silicates in a Protostellar EnvelopeApr 22 2011We present the Spitzer Space Telescope Infrared Spectrograph spectrum of the Orion A protostar HOPS-68. The mid-infrared spectrum reveals crystalline substructure at 11.1, 16.1, 18.8, 23.6, 27.9, and 33.6 microns superimposed on the broad 9.7 and 18 micron ... More
Retired A Stars and Their Companions VI. A Pair of Interacting Exoplanet Pairs Around the Subgiants 24 Sextanis and HD200964Jul 26 2010We report radial velocity measurements of the G-type subgiants 24 Sextanis (=HD90043) and HD200964. Both are massive, evolved stars that exhibit periodic variations due to the presence of a pair of Jovian planets. Photometric monitoring with the T12 0.80m ... More
Old, Rich, and Eccentric: Two Jovian Planets Orbiting Evolved Metal-Rich StarsApr 17 2009Jun 20 2009We present radial velocity measurements of two stars observed as part of the Lick Subgiants Planet Search and the Keck N2K survey. Variations in the radial velocities of both stars reveal the presence of Jupiter-mass exoplanets in highly eccentric orbits. ... More
Lattice symmetries and the topological protected transport of colloidal particlesJul 04 2017The topologically protected transport of colloidal particles on top of magnetic patterns of all possible single lattice constant two dimensional magnetic point group symmetries is studied experimentally, theoretically, and with numerical simulations. ... More
Retired A Stars and Their Companions. III. Comparing the Mass-Period Distributions of Planets Around A-Type Stars and Sun-Like StarsDec 02 2009We present an analysis of ~5 years of Lick Observatory radial velocity measurements targeting a uniform sample of 31 intermediate-mass subgiants (1.5 < M*/Msun < 2.0) with the goal of measuring the occurrence rate of Jovian planets around (evolved) A-type ... More
Critical Point and Deconfinement from Dyson-Schwinger EquationsAug 21 2013We employ the Dyson-Schwinger equations for quark and gluon propagators in order to study QCD with 2+1 flavours at finite temperature and density. In a suitable truncation for these equations, we determine the position of the critical end-point as well ... More
Octet and Decuplet Baryons in a Confining and Covariant Diquark-Quark ModelJul 30 1999We treat baryons as bound states of scalar or axialvector diquarks and a constituent quark which interact through quark exchange. We obtain fully four-dimensional wave functions for both octet and decuplet baryons as solutions of the corresponding Bethe-Salpeter ... More
Spin-polarized quasiparticle transport in exchange-split superconducting aluminum on europium sulfideAug 01 2014We report on nonlocal spin transport in mesoscopic superconducting aluminum wires in contact with the ferromagnetic insulator europium sulfide. We find spin injection and long-range spin transport in the regime of the exchange splitting induced by europium ... More
A Search for Lost Planets in the Kepler Multi-planet Systems and the Discovery of the Long-period, Neptune-sized Exoplanet Kepler-150 fMar 27 2017The vast majority of the 4700 confirmed planets and planet candidates discovered by the Kepler mission were first found by the Kepler pipeline. In the pipeline, after a transit signal is found, all data points associated with those transits are removed, ... More
High-Precision Optical Measurement of the 2S Hyperfine Interval in Atomic HydrogenMay 16 2003We have applied an optical method to the measurement of the 2S hyperfine interval in atomic hydrogen. The interval has been measured by means of two-photon spectroscopy of the 1S-2S transition on a hydrogen atomic beam shielded from external magnetic ... More
Coherent beam-beam experiments and implications for head-on compensationOct 21 2014In polarized proton operation in the Relativistic Heavy Ion Collider (RHIC) coherent beam-beam modes are routinely observed with beam transfer function measurements. These modes can become unstable under external excitation or in the presence of impedance. ... More
Symmetry Content and Observation of Charged Collective Excitations for Graphene in Strong Magnetic FieldsMay 18 2010Oct 13 2010We show that graphene in a strong magnetic field with partially filled Landau levels sustains charged collective excitations, which are bound states of three-particle complexes. Some of these states are optically bright and may be detected in spectroscopy ... More
The phase structure of QCD for heavy quarksSep 30 2014We investigate the nature of the deconfinement and Roberge-Weiss transition in the heavy quark regime for finite real and imaginary chemical potential within the functional approach to continuum QCD. We extract the critical phase boundary between the ... More
Aspects of confinement from QCD correlation functionsDec 15 2008We discuss the properties of ghost and gluon propagators in Landau gauge Yang-Mills theory and their relation to the confinement problem. In general two types of infrared behavior of these functions are allowed from their functional equations: scaling ... More
On the infrared behavior of Landau gauge Yang-Mills theoryOct 13 2008Jul 24 2009We discuss the properties of ghost and gluon propagators in the deep infrared momentum region of Landau gauge Yang-Mills theory. Within the framework of Dyson-Schwinger equations and the functional renormalization group we demonstrate that it is only ... More