Results for "M. J. N. L. Benders"

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Generative adversarial network for segmentation of motion affected neonatal brain MRIJun 11 2019Automatic neonatal brain tissue segmentation in preterm born infants is a prerequisite for evaluation of brain development. However, automatic segmentation is often hampered by motion artifacts caused by infant head movements during image acquisition. ... More
Surface Symmetry Energy of Nuclear Energy Density FunctionalsDec 28 2010We study the bulk deformation properties of the Skyrme nuclear energy density functionals. Following simple arguments based on the leptodermous expansion and liquid drop model, we apply the nuclear density functional theory to assess the role of the surface ... More
Shell-model calculation of isospin-symmetry breaking correction to superallowed Fermi beta-decayDec 18 2016Dec 23 2016We investigate the radial-overlap part of the isospin-symmetry breaking correction to superallowed $0^+\to 0^+$-decay using the shell-model approach similar to that of Refs. [1, 2]. The 8 sd-shell emitters with masses between $A=22$ and $A=38$ have been ... More
Automatic segmentation of MR brain images with a convolutional neural networkApr 11 2017Automatic segmentation in MR brain images is important for quantitative analysis in large-scale studies with images acquired at all ages. This paper presents a method for the automatic segmentation of MR brain images into a number of tissue classes using ... More
Automatic brain tissue segmentation in fetal MRI using convolutional neural networksJun 11 2019MR images of fetuses allow clinicians to detect brain abnormalities in an early stage of development. The cornerstone of volumetric and morphologic analysis in fetal MRI is segmentation of the fetal brain into different tissue classes. Manual segmentation ... More
Intense Star-formation and Feedback at High Redshift: Spatially-resolved Properties of the z=2.6 Submillimeter Galaxy SMMJ14011+0252Nov 24 2006Nov 25 2006We present a detailed analysis of the spatially-resolved properties of the lensed submillimeter galaxy SMMJ14011+0252 at z=2.56, combining deep near-infrared integral-field data obtained with SPIFFI on the VLT with other multi-wavelength data sets. The ... More
Automatic segmentation of the intracranialvolume in fetal MR imagesJul 31 2017MR images of the fetus allow non-invasive analysis of the fetal brain. Quantitative analysis of fetal brain development requires automatic brain tissue segmentation that is typically preceded by segmentation of the intracranial volume (ICV). This is challenging ... More
Estimating Stochastic Gravitational Wave Backgrounds with Sagnac CalibrationApr 16 2001Aug 03 2001Armstrong et al. have recently presented new ways of combining signals to precisely cancel laser frequency noise in spaceborne interferometric gravitational wave detectors such as LISA. One of these combinations, the symmetrized Sagnac observable, is ... More
Properties of nuclei in the nobelium region studied within the covariant, Skyrme, and Gogny energy density functionalsApr 13 2015Jul 28 2015We calculate properties of the ground and excited states of nuclei in the nobelium region for proton and neutron numbers of 92 <= Z <= 104 and 144 <= N <= 156, respectively. We use three different energy-density-functional (EDF) approaches, based on covariant, ... More
Observation of Asymmetric Transport in Structures with Active NonlinearitiesJan 30 2013A mechanism for asymmetric transport based on the interplay between the fundamental symmetries of parity (P) and time (T) with nonlinearity is presented. We experimentally demonstrate and theoretically analyze the phenomenon using a pair of coupled van ... More
The GL 569 Multiple SystemMar 07 2006Apr 04 2006We report the results of high spectral and angular resolution infrared observations of the multiple system GL 569 A and B that were intended to measure the dynamical masses of the brown dwarf binary believed to comprise GL 569 B. Our analysis did not ... More
The supermassive black hole in NGC4486a detected with SINFONI at the VLTMay 12 2007The near-infrared integral field spectrograph SINFONI at the ESO VLT opens a new window for the study of central supermassive black holes. With a near-IR spatial resolution similar to HST optical and the ability to penetrate dust it provides the possibility ... More
Depleted Galaxy Cores and Dynamical Black Hole MassesOct 20 2013Nov 12 2013Shallow cores in bright, massive galaxies are commonly thought to be the result of scouring of stars by mergers of binary supermassive black holes. Past investigations have suggested correlations between the central black hole mass and the stellar light ... More
SPIFFI observations of the starburst SMMJ14011+0252: Already old, fat, and rich by z = 2.565Mar 10 2004Mar 17 2004Using the SPectrometer for Infrared Faint Field Imaging (SPIFFI) on the ESO VLT, we have obtained J, H, and K band integral field spectroscopy of the z = 2.565 luminous submillimeter galaxy SMMJ14011+0252. A global spectrum reveals the brighter of this ... More
PT phase transition in multidimensional quantum systemsJun 22 2012Non-Hermitian PT-symmetric quantum-mechanical Hamiltonians generally exhibit a phase transition that separates two parametric regions, (i) a region of unbroken PT symmetry in which the eigenvalues are all real, and (ii) a region of broken PT symmetry ... More
Extending PT symmetry from Heisenberg algebra to E2 algebraSep 16 2010The E2 algebra has three elements, J, u, and v, which satisfy the commutation relations [u,J]=iv, [v,J]=-iu, [u,v]=0. We can construct the Hamiltonian H=J^2+gu, where g is a real parameter, from these elements. This Hamiltonian is Hermitian and consequently ... More
Density functional theory and Kohn-Sham scheme for self-bound systemsApr 01 2009Nov 10 2009We demonstrate how the separation of the total energy of a self-bound system into a functional of the internal one-body Fermionic density and a function of an arbitrary wave vector describing the center-of-mass kinetic energy can be used to set-up an ... More
alpha-decay chains of Z=114, A=289 and Z=118, A=293 in the relativistic mean-field modelNov 19 1999A comparison of calculated and experimental Q_alpha values of superheavy even-even nuclei and a few selected odd-N nuclei is presented in the framework of the relativistic mean-field model with the parameterization NL-Z2. Blocking effects are found to ... More
Numerical Evidence that the Perturbation Expansion for a Non-Hermitian $\mathcal{PT}$-Symmetric Hamiltonian is StieltjesOct 03 2000Recently, several studies of non-Hermitian Hamiltonians having $\mathcal{PT}$ symmetry have been conducted. Most striking about these complex Hamiltonians is how closely their properties resemble those of conventional Hermitian Hamiltonians. This paper ... More
Pan-STARRS1 variability of XMM-COSMOS AGN. I. Impact on photometric redshiftsOct 06 2015[Abbreviated] Upcoming large area sky surveys like EUCLID and eROSITA crucially depend on accurate photometric redshifts (photo-z). The identification of variable sources, such as AGNs, and the achievable redshift accuracy for varying objects are important ... More
Comment on ``Structure of exotic nuclei and superheavy elements in a relativistic shell model''Jun 12 2001Sep 02 2002A recent paper [M. Rashdan, Phys. Rev. C 63, 044303 (2001)] introduces the new parameterization NL-RA1 of the relativistic mean-field model which is claimed to give a better description of nuclear properties than earlier ones. Using this model ^{298}114 ... More
Extrapolation of mean-field models to superheavy nucleiOct 29 2000The extrapolation of self-consistent nuclear mean-field models to the region of superheavy elements is discussed with emphasis on the extrapolating power of the models. The predictions of modern mean-field models are confronted with recent experimental ... More
A hot Jupiter transiting a mid-K dwarf found in the pre-OmegaCam Transit SurveyAug 29 2013We describe the pre-OmegaTranS project, a deep survey for transiting extra-solar planets in the Carina region of the Galactic Disk. In 2006-2008 we observed a single dense stellar field with a very high cadence of ~2min using the ESO Wide Field Imager ... More
Further explorations of Skyrme-Hartree-Fock-Bogoliubov mass formulas. III: Role of particle-number projectionSep 02 2004Starting from HFB-6, we have constructed a new mass table, referred to as HFB-8, including all the 9200 nuclei lying between the two drip lines over the range of Z and N > 6 and Z < 122. It differs from HFB-6 in that the wave function is projected on ... More
Further explorations of Skyrme-Hartree-Fock-Bogoliubov mass formulas. II: Role of the effective massNov 24 2003We have constructed four new complete mass tables, referred to as HFB-4 to HFB-7, each one including all the 9200 nuclei lying between the two drip lines over the range of Z and N>8 and Z<120. HFB-4 and HFB-5 have the isoscalar effective mass M*_s$ constrained ... More
SPHERICALLY SYMMETRIC RANDOM WALKS II. DIMENSIONALLY DEPENDENT CRITICAL BEHAVIORJun 06 1995A recently developed model of random walks on a $D$-dimensional hyperspherical lattice, where $D$ is {\sl not} restricted to integer values, is extended to include the possibility of creating and annihilating random walkers. Steady-state distributions ... More
Wavepacket Self-imaging and Giant Recombinations via Stable Bloch-Zener Oscillations in Photonic Lattices with Local ${\cal PT}$-SymmetryJul 04 2015We propose a family of {\it local} $\cal{PT}$-symmetric photonic lattices with transverse index gradient $\omega$, where the emergence of {\it stable} Bloch-Zener oscillations are controlled by the degree of non-Hermiticity $\gamma$ of the lattice. In ... More
Non-parametric modeling of the intra-cluster gas using APEX-SZ bolometer imaging dataNov 20 2009Sep 17 2010We demonstrate the usability of mm-wavelength imaging data obtained from the APEX-SZ bolometer array to derive the radial temperature profile of the hot intra-cluster gas out to radius r_500 and beyond. The goal is to study the physical properties of ... More
Finite-Dimensional PT-Symmetric HamiltoniansMar 29 2003This paper investigates finite-dimensional representations of PT-symmetric Hamiltonians. In doing so, it clarifies some of the claims made in earlier papers on PT-symmetric quantum mechanics. In particular, it is shown here that there are two ways to ... More
Calculation of the Hidden Symmetry Operator in PT-Symmetric Quantum MechanicsNov 26 2002In a recent paper it was shown that if a Hamiltonian H has an unbroken PT symmetry, then it also possesses a hidden symmetry represented by the linear operator C. The operator C commutes with both H and PT. The inner product with respect to CPT is associated ... More
All Hermitian Hamiltonians Have ParityNov 20 2002Nov 26 2002It is shown that if a Hamiltonian $H$ is Hermitian, then there always exists an operator P having the following properties: (i) P is linear and Hermitian; (ii) P commutes with H; (iii) P^2=1; (iv) the nth eigenstate of H is also an eigenstate of P with ... More
SPHERICALLY SYMMETRIC RANDOM WALKS III. POLYMER ADSORPTION AT A HYPERSPHERICAL BOUNDARYJun 06 1995A recently developed model of random walks on a $D$-dimensional hyperspherical lattice, where $D$ is {\sl not} restricted to integer values, is used to study polymer growth near a $D$-dimensional attractive hyperspherical boundary. The model determines ... More
Electrically controlled long-distance spin transport through an antiferromagnetic insulatorMay 07 2018Spintronics uses spins, the intrinsic angular momentum of electrons, as an alternative for the electron charge. Its long-term goal is in the development of beyond-Moore low dissipation technology devices. Recent progress demonstrated the long-distance ... More
Two-Point Green's Function in PT-Symmetric TheoriesAug 20 2002The Hamiltonian $H={1\over2} p^2+{1\over2}m^2x^2+gx^2(ix)^\delta$ with $\delta,g\geq0$ is non-Hermitian, but the energy levels are real and positive as a consequence of ${\cal PT}$ symmetry. The quantum mechanical theory described by $H$ is treated as ... More
Complex periodic potentials with real band spectraOct 27 1998This paper demonstrates that complex PT-symmetric periodic potentials possess real band spectra. However, there are significant qualitative differences in the band structure for these potentials when compared with conventional real periodic potentials. ... More
Universality in Random Walk Models with Birth and DeathJun 06 1995Models of random walks are considered in which walkers are born at one location and die at all other locations with uniform death rate. Steady-state distributions of random walkers exhibit dimensionally dependent critical behavior as a function of the ... More
Wilson Polynomials and the Lorentz Transformation Properties of the Parity OperatorDec 01 2004The parity operator for a parity-symmetric quantum field theory transforms as an infinite sum of irreducible representations of the homogeneous Lorentz group. These representations are connected with Wilson polynomials.
SPHERICALLY SYMMETRIC RANDOM WALKS I. REPRESENTATION IN TERMS OF ORTHOGONAL POLYNOMIALSJun 06 1995Spherically symmetric random walks in arbitrary dimension $D$ can be described in terms of Gegenbauer (ultraspherical) polynomials. For example, Legendre polynomials can be used to represent the special case of two-dimensional spherically symmetric random ... More
Beta decay of r-process waiting-point nuclei in a self-consistent approachFeb 23 1999Beta-decay rates for spherical neutron-rich r-process waiting-point nuclei are calculated within a fully self-consistent Quasiparticle Random-Phase Approximation, formulated in the Hartree-Fock-Bogolyubov canonical single-particle basis. The same Skyrme ... More
An Upper Bound on the Flux Ratio of rho CrB's Companion at 1.6umSep 17 2004We use high resolution infrared spectroscopy to investigate the 2001 report by Gatewood and colleagues that rho CrB's candidate extrasolar planet companion is really a low-mass star with mass 0.14+-0.05 Msun. We do not detect evidence of such a companion; ... More
Beyond mean-field study of elastic and inelastic electron scattering off nucleiOct 09 2014Jan 21 2015Electron scattering provides a powerful tool to determine charge distributions and transition densities of nuclei. This tool will soon be available for short-lived neutron-rich nuclei. [Purpose] Beyond mean-field methods have been successfully applied ... More
Gamow-Teller strength and the spin-isospin coupling constants of the Skyrme energy functionalDec 17 2001We investigate the effects of the spin-isospin channel of the Skyrme energy functional on predictions for Gamow-Teller distributions and superdeformed rotational bands. We use the generalized Skyrme interaction SkO' to describe even-even ground states ... More
Skyrme functional from a three-body pseudo-potential of second-order in gradients. Formalism for central termsOct 02 2013In one way or the other, all modern parametrizations of the nuclear energy density functional (EDF) do not respect the exchange symmetry associated with Pauli's principle. It has been recently shown that this practice jeopardizes multi-reference (MR) ... More
The KMOS$^\mathrm{3D}$ Survey: rotating compact star forming galaxies and the decomposition of integrated line widthsNov 06 2017Mar 14 2018Using integral field spectroscopy we investigate the kinematic properties of 35 massive centrally-dense and compact star-forming galaxies (${\log{\overline{M}_*}}=11.1$, $\log{(\Sigma_\mathrm{1kpc})}>9.5$, $\log{(M_\ast/r_e^{1.5})}>10.3$) at $z\sim0.7-3.7$ ... More
Systematics of low-lying states of even-even nuclei in the neutron-deficient lead region from a beyond-mean-field calculationNov 09 2012Nuclei located in the neutron-deficient Pb region have a complex structure, rapidly evolving as a function of neutron and proton numbers. The most famous example is $^{186}$Pb where the three lowest levels are $0^+$ states, the two excited $0^+$ ones ... More
The KMOS^3D Survey: design, first results, and the evolution of galaxy kinematics from 0.7<z<2.7Sep 24 2014Dec 12 2014We present the KMOS^3D survey, a new integral field survey of over 600 galaxies at 0.7<z<2.7 using KMOS at the Very Large Telescope (VLT). The KMOS^3D survey utilizes synergies with multi-wavelength ground and space-based surveys to trace the evolution ... More
Comparison of LISA and Atom Interferometry for Gravitational Wave Astronomy in SpaceJun 14 2011One of the atom interferometer gravitational wave missions proposed by Dimopoulos et al.1 in 2008 was called AGIS-Sat. 2. It had a suggested gravitational wave sensitivity set by the atom state detection shot noise level that started at 1 mHz, was comparable ... More
The angular momentum distribution and baryon content of star forming galaxies at z~1-3Oct 12 2015May 19 2016We analyze the angular momenta of massive star forming galaxies (SFGs) at the peak of the cosmic star formation epoch (z~0.8-2.6). Our sample of ~360 log(M*/Msun) ~ 9.3-11.8 SFGs is mainly based on the KMOS3D and SINS/zC-SINF surveys of H$\alpha$ kinematics, ... More
Molecular gas in the centre of nearby galaxies from VLT/SINFONI integral field spectroscopy - I. Morphology and mass inventoryOct 15 2012We present the first results of an analysis of the properties of the molecular gas in the nuclear regions (r < 300 pc) of a sample of six nearby galaxies, based on new high spatial resolution observations obtained in the K-band with the near-infrared ... More
The evolution of the Tully-Fisher relation between z~2.3 and z~0.9 with KMOS^3DMar 13 2017Jun 07 2017We investigate the stellar mass and baryonic mass Tully-Fisher relations (TFRs) of massive star-forming disk galaxies at redshift z~2.3 and z~0.9 as part of the KMOS^3D integral field spectroscopy survey. Our spatially resolved data allow reliable modelling ... More
Pairing gaps from nuclear mean-field modelsMay 10 2000We discuss the pairing gap, a measure for nuclear pairing correlations, in chains of spherical, semi-magic nuclei in the framework of self-consistent nuclear mean-field models. The equations for the conventional BCS model and the approximate projection-before-variation ... More
Dual PT-Symmetric Quantum Field TheoriesAug 15 2005Some quantum field theories described by non-Hermitian Hamiltonians are investigated. It is shown that for the case of a free fermion field theory with a $\gamma_5$ mass term the Hamiltonian is $\cal PT$-symmetric. Depending on the mass parameter this ... More
Dark matter halo properties from galaxy-galaxy lensingMar 25 2013May 03 2013We present results for a galaxy-galaxy lensing study based on imaging data from the Canada-France-Hawaii Telescope Legacy Survey Wide. From a 12 million object multi-colour catalogue for 124 deg^2 of photometric data in the u*g'r'i'z' filters we compute ... More
Simulations of an ultracold, neutral plasma with equal massesAug 21 2014The results of a theoretical investigation of an ultracold, neutral plasma composed of equal mass positive and negative charges are reported. In our simulations, the plasma is created by the fast dissociation of a neutral particle. The temperature of ... More
Systematics of Fission Barriers in Superheavy ElementsFeb 20 2003Feb 03 2004We investigate the systematics of fission barriers in superheavy elements in the range Z = 108-120 and N = 166-182. Results from two self-consistent models for nuclear structure, the relativistic mean-field (RMF) model as well as the non-relativistic ... More
Submillimeter Galaxies as Tracers of Mass Assembly at Large MMar 08 2004Luminous submillimeter galaxies (SMGs) have been known for some time to produce a substantial fraction of the far-IR/submillimeter background. New observations show that these systems are not only very luminous, but also very massive. Here we present ... More
Radiation Hardness of Graphene and MoS2 Field Effect Devices Against Swift Heavy Ion IrradiationApr 12 2013We have investigated the deterioration of field effect transistors based on twodimensional materials due to irradiation with swift heavy ions. Devices were prepared with exfoliated single layers of MoS2 and graphene, respectively. They were characterized ... More
Pairing Gap and Polarisation EffectsOct 08 1999The phenomenological adjustment of the nuclear pairing strength is usually performed with respect to the odd-even staggering of the binding energies. We find that the results strongly depend on the way in which the ground states of the odd nuclei are ... More
Consequences of the center-of-mass correction in nuclear mean-field modelsOct 08 1999We study the influence of the scheme for the correction for spurious center-of-mass motion on the fit of effective interactions for self-consistent nuclear mean-field calculations. We find that interactions with very simple center-of-mass correction have ... More
An HFB scheme in natural orbitalsMay 30 1997We present a formulation of the Hartree-Fock-Bogoliubov (HFB) equations which solves the problem directly in the basis of natural orbitals. This provides a very efficient scheme which is particularly suited for large scale calculations on coordinate-space ... More
Probing the role of proton cross-shell excitations in 70Ni using nucleon knockout reactionsSep 15 2019The neutron-rich Ni isotopes have attracted attention in recent years due to the occurrence of shape or configuration coexistence. We report on the difference in population of excited final states in 70Ni following gamma-ray tagged one-proton, one-neutron, ... More
Mean-field models and superheavy elementsDec 28 2000We discuss the performance of two widely used nuclear mean-field models, the relativistic mean-field theory (RMF) and the non-relativistic Skyrme-Hartree-Fock approach (SHF), with particular emphasis on the description of superheavy elements (SHE). We ... More
Constraining the surface properties of effective Skyrme interactionsJun 04 2016The purpose of this study is threefold: first, to identify a scheme for the determination of the surface energy coefficient a_surf that offers the best compromise between robustness, precision, and numerical efficiency; second, to analyze the correlation ... More
The tensor part of the Skyrme energy density functional. I. Spherical nucleiApr 05 2007Jul 27 2007We perform a systematic study of the impact of the J^2 tensor term in the Skyrme energy functional on properties of spherical nuclei. In the Skyrme energy functional, the tensor terms originate both from zero-range central and tensor forces. We build ... More
Measurement of Lifetimes in 23MgAug 28 2015Several lifetimes in 23Mg have been determined for the first time using the Doppler-shift attenuation method. A Monte Carlo simulation code has been written to model the gamma-ray line shape. An upper limit of 12 fs at the 95% C.L. has been obtained for ... More
Multi-frequency imaging of the galaxy cluster Abell 2163 using the Sunyaev-Zel'dovich EffectFeb 12 2009Nov 06 2009We used the APEX-SZ and LABOCA bolometer cameras on the APEX telescope to map the decrement of the Sunyaev-Zeldovich effect at 150 GHz and the increment at 345 GHz toward the galaxy cluster Abell 2163. The SZE images were used to model the radial density ... More
Optimal Shape of a BlobMar 08 2007This paper presents the solution to the following optimization problem: What is the shape of the two-dimensional region that minimizes the average L_p distance between all pairs of points if the area of this region is held fixed? [The L_p distance between ... More
Galaxy cluster scaling relations measured with APEX-SZApr 28 2014Apr 27 2015We present thermal Sunyaev-Zel'dovich effect (SZE) measurements for 42 galaxy clusters observed at 150 GHz with the APEX-SZ experiment. For each cluster, we model the pressure profile and calculate the integrated Comptonization $Y$ to estimate the total ... More
Performance of a low-parasitic frequency-domain multiplexing readoutJul 21 2019Frequency-domain multiplexing is a readout technique for transition edge sensor bolometer arrays used on modern CMB experiments, including the SPT-3G receiver. Here, we present design details and performance measurements for a low-parasitic frequency-domain ... More
Lyman Break Galaxies Under a Microscope: The Small Scale Dynamics and Mass of an Arc in the Cluster 1E0657-56Jun 21 2006Using the near-infrared integral-field spectrograph SPIFFI on the VLT, we have studied the spatially-resolved dynamics in the z=3.2 strongly lensed galaxy 1E0657-56 ``arc+core''. The lensing configuration suggests that the high surface brightness ``core'' ... More
Weak-lensing mass calibration of the Sunyaev-Zel'dovich effect using APEX-SZ galaxy clustersApr 10 2018The use of galaxy clusters as precision cosmological probes relies on an accurate determination of their masses. However, inferring the relationship between cluster mass and observables from direct observations is difficult and prone to sample selection ... More
Constraints on the High-l Power Spectrum of Millimeter-wave Anisotropies from APEX-SZApr 27 2009Aug 15 2009We present measurements of the angular power spectrum of millimeter wave anisotropies with the APEX-SZ instrument. APEX-SZ has mapped 0.8 square degrees of sky at a frequency of 150 GHz with an angular resolution of 1'. These new measurements significantly ... More
Introduction to PT-Symmetric Quantum TheoryJan 11 2005In most introductory courses on quantum mechanics one is taught that the Hamiltonian operator must be Hermitian in order that the energy levels be real and that the theory be unitary (probability conserving). To express the Hermiticity of a Hamiltonian, ... More
The SINFONI Black Hole Survey: The Black Hole Fundamental Plane revisited and the paths of (co-) evolution of supermassive black holes and bulgesJan 05 2016Jan 20 2016We investigate the correlations between the black hole mass $M_{BH}$, the velocity dispersion $\sigma$, the bulge mass $M_{Bu}$, the bulge average spherical density $\rho_h$ and its spherical half mass radius $r_h$, constructing a database of 97 galaxies ... More
Sunyaev-Zel'dovich Effect Observations of the Bullet Cluster (1E 0657-56) with APEX-SZJul 26 2008Jun 06 2009We present observations of the Sunyaev-Zel'dovich effect (SZE) in the Bullet cluster (1E 0657--56) using the APEX-SZ instrument at 150 GHz with a resolution of 1 arcmin. The main results are maps of the SZE in this massive, merging galaxy cluster. The ... More
Making Sense of Non-Hermitian HamiltoniansMar 09 2007The Hamiltonian H specifies the energy levels and time evolution of a quantum theory. A standard axiom of quantum mechanics requires that H be Hermitian because Hermiticity guarantees that the energy spectrum is real and that time evolution is unitary ... More
Faster than Hermitian Time EvolutionDec 23 2007Dec 27 2007For any pair of quantum states, an initial state |I> and a final quantum state |F>, in a Hilbert space, there are many Hamiltonians H under which |I> evolves into |F>. Let us impose the constraint that the difference between the largest and smallest eigenvalues ... More
Almost zero-dimensional PT-symmetric quantum field theoriesMar 19 2010In 1992 Bender, Boettcher, and Lipatov proposed in two papers a new and unusual nonperturbative calculational tool in quantum field theory. The objective was to expand the Green's functions of the quantum field theory as Taylor series in powers of the ... More
Pairing correlations beyond the mean fieldNov 09 2006We discuss dynamical pairing correlations in the context of configuration mixing of projected self-consistent mean-field states, and the origin of a divergence that might appear when such calculations are done using an energy functional in the spirit ... More
Properties of M31. III: Candidate Beat Cepheids from PS1 PAndromeda Data and Their Implication on Metallicity GradientAug 29 2013Oct 12 2013We present a sample of M31 beat Cepheids from the Pan-STARRS 1 PAndromeda campaign. By analyzing three years of PAndromeda data, we identify seventeen beat Cepheids, spreading from a galactocentric distance of 10 to 16 kpc. Since the relation between ... More
The Influence of Dark Matter Halos on Dynamical Estimates of Black Hole Mass: Ten New Measurements for High-sigma Early-Type GalaxiesJun 05 2013Jul 15 2013Adaptive-Optics assisted SINFONI observations of the central regions of ten early-type galaxies are presented. Based primarily on the SINFONI kinematics, ten black hole masses occupying the high-mass regime of the M_BH-sigma relation are derived using ... More
Digital frequency domain multiplexing readout electronics for the next generation of millimeter telescopesJul 11 2014Frequency domain multiplexing (fMux) is an established technique for the readout of transition-edge sensor (TES) bolometers in millimeter-wavelength astrophysical instrumentation. In fMux, the signals from multiple detectors are read out on a single pair ... More
Molecular gas in the centre of nearby galaxies from VLT/SINFONI integral field spectroscopy - II. KinematicsDec 02 2013We present an analysis of the H2 emission-line gas kinematics in the inner < 4 arcsec radius of six nearby spiral galaxies, based on AO-assisted integral-field observations obtained in the K-band with SINFONI/VLT. Four of the six galaxies in our sample ... More
Properties of M31. IV: Candidate Luminous Blue Variables from PAndromedaMar 26 2014We perform a study on the optical and infrared photometric properties of known luminous blue variables (LBVs) in M31 using the sample of LBV candidates from the Local Group Galaxy Survey (Massey et al. 2007). We find that M31 LBV candidates show photometric ... More
Early onset of ground-state deformation in the neutron-deficient polonium isotopesOct 11 2010In-source resonant ionization laser spectroscopy of the even-$A$ polonium isotopes $^{192-210,216,218}$Po has been performed using the $6p^37s$ $^5S_2$ to $6p^37p$ $^5P_2$ ($\lambda=843.38$ nm) transition in the polonium atom (Po-I) at the CERN ISOLDE ... More
Photometric Redshifts and Model Spectral Energy Distributions of Galaxies From the SDSS-III BOSS DR10 DataMay 05 2015May 07 2015We construct a set of model spectra specifically designed to match the colours of the BOSS CMASS galaxies and to be used with photometric redshift template fitting techniques. As a basis we use a set of spectral energy distributions (SEDs) of single and ... More
Optical Asymmetry Induced by PT-symmetric Nonlinear Fano ResonancesOct 09 2013We introduce a new type of Fano resonances, realized in a photonic circuit which consists of two nonlinear PT-symmetric micro-resonators side-coupled to a waveguide, which have line-shape and resonance position that depends on the direction of the incident ... More
The stellar mass function of galaxies to z ~ 5 in the Fors Deep and GOODS-S fieldsDec 07 2004We present a measurement of the evolution of the stellar mass function (MF) of galaxies and the evolution of the total stellar mass density at 0<z<5. We use deep multicolor data in the Fors Deep Field (FDF; I-selected reaching I_AB=26.8) and the GOODS-S/CDFS ... More
Self-Consistent Description of Multipole Strength in Exotic Nuclei I: MethodJul 29 2004We use the canonical Hartree-Fock-Bogoliubov basis to implement a completely self-consistent quasiparticle-random-phase approximation with arbitrary Skyrme energy density functionals and density-dependent pairing functionals. The point of the approach ... More
Galaxy environment in the 3D-HST fields. Witnessing the onset of satellite quenching at z ~ 1-2Nov 22 2016We make publicly available a catalog of calibrated environmental measures for galaxies in the five 3D-HST/CANDELS deep fields. Leveraging the spectroscopic and grism redshifts from the 3D-HST survey, multi wavelength photometry from CANDELS, and wider ... More
The Munich Near-Infrared Cluster Survey (MUNICS) -- II. The K-Band Luminosity Function of Field Galaxies to z ~ 1.2Jun 15 2003(Abriged) We present a measurement of the evolution of the rest-frame K-band luminosity function to z ~ 1.2 using a sample of more than 5000 K-selected galaxies drawn from the MUNICS dataset. Distances and absolute K-band magnitudes are derived using ... More
The Munich Near--Infrared Cluster Survey (MUNICS) -- VI. The stellar masses of K-band selected field galaxies to z ~ 1.2Mar 01 2004Apr 20 2004We present a measurement of the evolution of the stellar mass function in four redshift bins at 0.4 < z < 1.2 using a sample of more than 5000 K-selected galaxies drawn from the MUNICS dataset. Our data cover the stellar mass range 10^10 < M/Msun < 10^12. ... More
The MUNICS Project: Galaxy Assembly at 0 < z < 1Dec 12 2003We summarize the results obtained from the MUNICS K-band selected Galaxy survey thus far. MUNICS is a wide-area, medium-deep, photometric and spectroscopic survey selected in the K band, targeting randomly-selected high Galactic latitude fields. It covers ... More
The Munich Near-Infrared Cluster Survey (MUNICS) - V. The evolution of the rest-frame K-band and J-band galaxy luminosity functions to z ~ 0.7Feb 25 2003We present spectroscopic follow-up observations of galaxies from the Munich Near-Infrared Cluster Survey (MUNICS). MUNICS is a wide-field medium-deep K'-band selected survey covering 1 square degree in the near-infrared K' and J pass-bands, and 0.35 square ... More
Millimeter Transient Point Sources in the SPTpol 100 Square Degree SurveyApr 12 2016Jul 28 2016The millimeter transient sky is largely unexplored, with measurements limited to follow-up of objects detected at other wavelengths. High-angular-resolution telescopes designed for measurement of the cosmic microwave background offer the possibility to ... More
CROMOS: A cryogenic near-infrared, multi-object spectrometer for the VLTAug 20 2001We discuss a cryogenic, multi-object near-infrared spectrometer as a second generation instrument for the VLT. The spectrometer combines 20 to 40 independent integral eld units (IFUs), which can be positioned by a cryogenic robot over the entire unvignetted ... More
M32-like galaxies: still very rare -- M32 analogues do not exist in the Leo groupOct 27 1997New observations of galaxies in the direction of the Leo group, which were classified as being candidates for M32-like dwarf galaxies by Ferguson & Sandage (1990), show that these galaxies are normal elliptical galaxies at redshifts between z=0.02 and ... More
Matrix representation of the time operatorJan 18 2012In quantum mechanics the time operator $\Theta$ satisfies the commutation relation $[\Theta,H]=i$, and thus it may be thought of as being canonically conjugate to the Hamiltonian $H$. The time operator associated with a given Hamiltonian $H$ is not unique ... More
Strongly baryon-dominated disk galaxies at the peak of galaxy formation ten billion years agoMar 13 2017In cold dark matter cosmology, the baryonic components of galaxies are thought to be mixed with and embedded in non-baryonic and non-relativistic dark matter, which dominates the total mass of the galaxy and its dark matter halo. In the local Universe, ... More
Optical Clock and Drag-Free Requirements for a Shapiro Time-Delay MissionJun 10 2011In the next decade or two, extremely accurate tests of general relativity under extreme conditions are expected from gravitational wave observations of binary black hole mergers with a wide range of mass ratios. In addition, major improvements are planned ... More