Results for "R. Harris"

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An anti-symmetric exclusion process for two particles on an infinite 1D latticeJul 11 2011Oct 10 2011A system of two biased, mutually exclusive random walkers on an infinite 1D lattice is studied whereby the intrinsic bias of one particle is equal and opposite to that of the other. The propogator for this system is solved exactly and expressions for ... More
Fourier's law on a one-dimensional optical random latticeMar 19 2010We study the transport properties of a one-dimensional hard-core bosonic lattice gas coupled to two particle reservoirs at different chemical potentials which generate a current flow through the system. In particular, the influence of random fluctuations ... More
Double epitaxy of tetragonal and hexagonal phases in the FeSe systemFeb 09 2019Feb 12 2019Epitaxial films which contains more than one crystallographic orientation are of interest due to the possibility of altered magnetic, electrical, and optical properties. Thin films of FeSe have been grown on single-crystal MgO substrates under conditions ... More
Strong Law of Large Numbers for Fragmentation ProcessesSep 17 2008In the spirit of a classical results for Crump-Mode-Jagers processes, we prove a strong law of large numbers for homogenous fragmentation processes. Specifically, for self-similar fragmentation processes, including homogenous processes, we prove the almost ... More
Computing Segre classes in arbitrary projective varietiesNov 21 2015Nov 26 2015We give an algorithm for computing Segre classes of subschemes of arbitrary projective varieties by computing degrees of a sequence of linear projections. Based on the fact that Segre classes of projective varieties commute with intersections by general ... More
On real growth and run-off companies in insurance ruin theoryNov 05 2015We study solvency of insurers in a comprehensive model where various economic factors affect the capital developments of the companies. The main interest is in the impact of real growth to ruin probabilities. The volume of the business is allowed to increase ... More
Categoricity and covering spacesDec 10 2014This thesis develops some of the basic model theory of covers of algebraic curves. In particular, an equivalence between the good model-theoretic behaviour of the modular j-function, and the openness of certain Galois representations in the Tate-modules ... More
Upper semicontinuity of the lamination hullSep 30 2016Let $K \subseteq \mathbb{R}^{2 \times 2}$ be a compact set, let $K^{rc}$ be its rank-one convex hull, and let $L(K)$ be its lamination convex hull. It is shown that the mapping $K \to \overline{L(K)}$ is not upper semicontinuous on the diagonal matrices ... More
Heat Kernels and CyclesMay 26 2005We use the heat kernel (on differential forms) on a compact Riemannian manifold to assign a real number to a k-tuple of cycles on the manifold satisfying certain conditions. If k is 2, this number is the ordinary topological linking number, an integer ... More
Monomial principalization in the singular settingOct 04 2013Apr 15 2014We generalize an algorithm by Goward for principalization of monomial ideals in nonsingular varieties to work on any scheme of finite type over a field. The normal crossings condition considered by Goward is weakened to the condition that components of ... More
A short proof of the thumbtack lemmaApr 17 2013We give a short proof of the main algebraic result of \cite{zilber2006covers}, also known as the `thumbtack lemma'.
Self-field and magnetic-flux quantum mechanicsApr 06 2005Self-field and quantized magnetic-flux are employed to generate the quantum numbers n, m, and l of atomic physics. Wave-particle duality is shown to be a natural outcome of having a particle and its self-field.
Incorrigible RepresentationsNov 12 2018Dec 25 2018As a consequence of his numerical local Langlands correspondence for $GL(n)$, Henniart deduced the following theorem: If $F$ is a nonarchimedean local field and if $\pi$ is an irreducible admissible representation of $GL(n,F)$, then, after a finite sequence ... More
Kostant's weight multiplicity formula and the Fibonacci numbersNov 28 2011It is well known that the dimension of a weight space for a finite dimensional representation of a simple Lie algebra is given by Kostant's weight multiplicity formula. We address the question of how many terms in the alternation contribute to the multiplicity ... More
Optimal angle of the holomorphic functional calculus for the classical Ornstein-Uhlenbeck operator on $L^p$Dec 20 2018We give a simple proof of the fact that the classical Ornstein-Uhlenbeck operator $L$ is R-sectorial of angle $arcsin|1-2/p|$ on $L^{p}(\mathbb{R}^{n},\exp(-|x|^2/2)dx)$ (for $1<p<\infty$). Applying the abstract holomorphic functional calculus theory ... More
Detection of a white dwarf companion to the white dwarf SDSSJ125733.63+542850.5Feb 25 2010May 16 2011SDSSJ125733.63+542850.5 (hereafter SDSSJ1257+5428) is a compact white dwarf binary from the Sloan Digital Sky Survey that exhibits high-amplitude radial velocity variations on a period of 4.56 hours. While an initial analysis suggested the presence of ... More
Severi Degrees in Cogenus 3Apr 06 1995In this short note, a new computation of the degree of the locus of 3-nodal plane curves in the linear system of degree d plane curves is given. The answer is expressed as a tautological class on a blow-up of the Hilbert scheme of 3 points in the plane. ... More
A Comprehensive New Detector for Detailed Study of the Quark Gluon Plasma, Initial Conditions and Spin Physics at RHIC IIJul 23 2004Jul 23 2004A case is presented for compelling physics at a high luminosity RHIC II collider and a comprehensive new detector system to address this physics. The experimental focus is on detailed jet tomography of the quark gluon plasma (QGP), measuring gluon saturation ... More
Correlations between Ground and Excited State Spectra of a Quantum DotSep 10 1997Oct 30 1997We have studied the ground and excited state spectra of a semiconductor quantum dot for successive numbers of electron occupancy using linear and nonlinear magnetoconductance measurements. We present the first observation of direct correlation between ... More
The Refined Gross-Prasad Conjecture for Unitary GroupsJan 02 2012Sep 08 2012Let F be a number field, A_F its ring of adeles, and let {\pi}_n and {\pi}_{n+1} be irreducible, cuspidal, automorphic representations of SO_n(A_F) and SO_{n+1}(A_F), respectively. In 1991, Benedict Gross and Dipendra Prasad conjectured the non-vanishing ... More
Exact hybrid particle/population simulation of rule-based models of biochemical systemsJan 29 2013Feb 05 2014Detailed modeling and simulation of biochemical systems is complicated by the problem of combinatorial complexity, an explosion in the number of species and reactions due to myriad protein-protein interactions and post-translational modifications. Rule-based ... More
The identification of HCN and HNC in Carbon Stars: Model Atmospheres, Synthetic Spectra and Fits to Observations in the 2.7-4.0 micron RegionJun 06 2003Model carbon star atmospheres and synthetic spectra have been calculated using the recent HCN/HNC vibration rotation linelist of Harris et al. (2002) ApJ, 578, 657. The calculations are repeated using only HCN lines and show that HNC has a significant ... More
Phonon drag thermopower and weak localizationJul 09 1998Previous experimental work on a two-dimensional (2D) electron gas in a Si-on-sapphire device led to the conclusion that both conductivity and phonon drag thermopower $S^g$ are affected to the same relative extent by weak localization. The present paper ... More
On the range of validity of the fluctuation theorem for stochastic Markovian dynamicsNov 21 2007Jun 06 2008We consider the fluctuations of generalized currents in stochastic Markovian dynamics. The large deviations of current fluctuations are shown to obey a Gallavotti-Cohen (GC) type symmetry in systems with a finite state space. However, this symmetry is ... More
Current fluctuations in stochastic systems with long-range memoryApr 09 2009Aug 07 2009We propose a method to calculate the large deviations of current fluctuations in a class of stochastic particle systems with history-dependent rates. Long-range temporal correlations are seen to alter the speed of the large deviation function in analogy ... More
Analytic solution of nonlinear fractional Burgers-type equation by invariant subspace methodJun 08 2013In this paper we study the analytic solutions of Burgers-type nonlinear fractional equations by means of the Invariant Subspace Method. We first study a class of nonlinear equations directly related to the time-fractional Burgers equation. Some generalizations ... More
Nonlinear time-fractional dispersive equationsOct 29 2014In this paper we study some cases of time-fractional nonlinear dispersive equations (NDEs) involving Caputo derivatives, by means of the invariant subspace method. This method allows to find exact solutions to nonlinear time-fractional partial differential ... More
Interkinetic nuclear migration in the zebrafish retina as a diffusive processMar 13 2019A major hallmark of neural development is the oscillatory movement of nuclei between the apical and basal surfaces of the neuroepithelium during the process of interkinetic nuclear migration (IKNM). Here, we employ long-term, rapid lightsheet and two-photon ... More
The electronic bands of CrD, CrH, MgD and MgH: application to the "deuterium test"Oct 01 2007Oct 11 2007We compute opacities for the electronic molecular band systems A 6Sigma+ -- X 6Sigma+ of CrH and CrD, and A 2Pi -- X 2Sigma+ of MgH and MgD. The opacities are computed by making use of existing spectroscopic constants for MgH and CrH. These constants ... More
Simulation and Optimization of an Astrophotonic ReformatterMay 02 2018Image slicing is a powerful technique in astronomy. It allows the instrument designer to reduce the slit width of the spectrograph, increasing spectral resolving power whilst retaining throughput. Conventionally this is done using bulk optics, such as ... More
The Euclidean distance degree of smooth complex projective varietiesJul 31 2017Nov 03 2017We obtain several formulas for the Euclidean distance degree (ED degree) of an arbitrary nonsingular variety in projective space: in terms of Chern and Segre classes, Milnor classes, Chern-Schwartz-MacPherson classes, and an extremely simple formula equating ... More
Analysis of new direct sampling indicators for far-field measurementsJan 08 2019Feb 12 2019This article focuses on the analysis of three direct sampling indicators which can be used for recovering scatterers from the far-field pattern of time-harmonic acoustic measurements. These methods fall under the category of sampling methods where an ... More
Whittaker periods, motivic periods, and special values of tensor product L-functionsAug 23 2013Aug 28 2014Let $\mathcal K$ be an imaginary quadratic field. Let $\Pi$ and $\Pi'$ be irreducible generic cohomological automorphic representation of $GL(n)/{\mathcal K}$ and $GL(n-1)/{\mathcal K}$, respectively. Each of them can be given two natural rational structures ... More
An a.e. lower bound for Hausdorff dimension under vertical projections in the Heisenberg groupNov 30 2018Mar 10 2019An improved a.e. lower bound is given for Hausdorff dimension under vertical projections in the first Heisenberg group.
Period relations and special values of Rankin-Selberg $L$-functionsAug 26 2016Dec 18 2016This is a survey of recent work on values of Rankin-Selberg $L$-functions of pairs of cohomological automorphic representations that are {\it critical} in Deligne's sense. The base field is assumed to be a CM field. Deligne's conjecture is stated in the ... More
On the adjoint representation of $\mathfrak{sl}_n$ and the Fibonacci numbersJun 07 2011We decompose the adjoint representation of $\mathfrak{sl}_{r+1}=\mathfrak {sl}_{r+1}(\mathbb C)$ by a purely combinatorial approach based on the introduction of a certain subset of the Weyl group called the \emph{Weyl alternation set} associated to a ... More
Categoricity of modular and Shimura curvesApr 17 2013Sep 14 2015We describe a model-theoretic setting for the study of Shimura varieties, and study the interaction between model theory and arithmetic geometry in this setting. In particular, we show that the model-theoretic statement of a certain $\mathcal{L}_{\omega_1, ... More
Zero range model of traffic flowApr 26 2005Oct 08 2005A multi--cluster model of traffic flow is studied, in which the motion of cars is described by a stochastic master equation. Assuming that the escape rate from a cluster depends only on the cluster size, the dynamics of the model is directly mapped to ... More
Deterministic parallel algorithms for fooling polylogarithmic juntas and the Lovasz Local LemmaOct 11 2016Many randomized algorithms can be derandomized efficiently using either the method of conditional expectations or probability spaces with low (almost-) independence. A series of papers, beginning with work by Luby (1988) and continuing with Berger & Rompel ... More
Near field imaging of small isotropic and extended anisotropic scatterersJan 12 2016Sep 11 2016In this paper, we consider two time-harmonic inverse scattering problems of reconstructing penetrable inhomogeneous obstacles from near field measurements. First we appeal to the Born approximation for reconstructing small isotropic scatterers via the ... More
Discovery Mass Reach for Excited Quarks at Hadron CollidersSep 11 1996If quarks are composite particles then excited states are expected. We estimate the discovery mass reach as a function of integrated luminosity for excited quarks decaying to dijets at the Tevatron, LHC, and a Very Large Hadron Collider (VLHC). At the ... More
UCD Candidates in the Hydra ClusterAug 10 2007NGC 3311, the giant cD galaxy in the Hydra cluster (A1060), has one of the largest globular cluster systems known. We describe new Gemini GMOS (g',i') photometry of the NGC 3311 field which reveals that the red, metal-rich side of its globular cluster ... More
Determination of step--edge barriers to interlayer transport from surface morphology during the initial stages of homoepitaxial growthMar 21 1995We use analytic formulae obtained from a simple model of crystal growth by molecular--beam epitaxy to determine step--edge barriers to interlayer transport. The method is based on information about the surface morphology at the onset of nucleation on ... More
Measure changes with extinctionNov 11 2008Dec 18 2008We consider a change of measure by a martingale $Z_t$ and clarify that in general $1/Z_t$ is only a supermartingale under the changed measure. We then give a necessary and sufficient condition for the event that the limit of the martingale is zero to ... More
Bipartite matrix-valued tensor product correlations that are not finitely representableJun 22 2018We consider the matrix-valued generalizations of bipartite tensor product quantum correlations and bipartite infinite-dimensional tensor product quantum correlations, respectively. These sets are denoted by $C_q^{(n)}(m,k)$ and $C_{qs}^{(n)}(m,k)$, respectively, ... More
Asymptotic convergence of spectral inverse iterations for stochastic eigenvalue problemsJun 12 2017We consider and analyze applying a spectral inverse iteration algorithm and its subspace iteration variant for computing eigenpairs of an elliptic operator with random coefficients. With these iterative algorithms the solution is sought from a finite ... More
Multiparametric shell eigenvalue problemsMar 10 2018Mar 16 2018The eigenproblem for thin shells of revolution under uncertainty in material parameters is discussed. Here the focus is on the smallest eigenpairs. Shells of revolution have natural eigenclusters due to symmetries, moreover, the eigenpairs depend on a ... More
Ricci-Positive geodesic flows and point-completion of static monopole fieldsSep 09 2018We use methods of complex analysis to extend the bundle structure across a removable point-singularity in a Sasakian three-manifold.
Upper semicontinuity of the lamination hullSep 30 2016Apr 24 2017Let $K \subseteq \mathbb{R}^{2 \times 2}$ be a compact set, let $K^{rc}$ be its rank-one convex hull, and let $L(K)$ be its lamination convex hull. It is shown that the mapping $K \to \overline{L(K)}$ is not upper semicontinuous on the diagonal matrices ... More
Classifying Possible Tilting of Oxygen Octahedra in PerovskitesDec 23 2010The list of possible commensurate phases obtained from the parent tetragonal phase of perovskites by allowing the tilting of octahedra of oxygen ions is reexamined. It is found that many structures allowed by symmetry are not consistent with the constraint ... More
Landau Potential for Multiferroic Mn_2GeO_4Jan 18 2017A high-order Landau potential for Mn_2GeO_4 is developed.
Landau Theory of Tilting of Oxygen Octahedra in PerovskitesJun 13 2011The list of possible commensurate phases obtained from the parent tetragonal phase of Ruddlesden-Popper systems, A$_{n+1}$B$_n$C$_{3n+1}$ for general $n$ due to a single phase transition involving the reorienting of octahedra of C (oxygen) ions is reexamined ... More
Phonons and their Coupling to Magnons in n=2 Ruddlesden-Popper CompoundsNov 30 2010Jan 25 2011The number of absorption and Raman optical modes for each Wyckoff orbit in the high-temperature tetragonal (I4/mmm) parent lattice of the Ruddlesden-Popper compounds Ca$_3$X$_2$O$_7$, with X=Mn or X=Ti is given. We analyze the effect of sequential perturbations ... More
Possible Orientationally Ordered States of Bucky-CubaneFeb 13 2009For temperatures above $T^*=130$K C$_{60} \cdot$C$_8$H$_8$ forms a cubic crystal consisting of two interpenetrating fcc sublattices, one of freely rotating Buckys C$_{60}$ and the other of orientationally ordered cubane C$_8$H$_8$. The crystal structure ... More
Spectroscopy with Multichannel Correlation RadiometersApr 20 2005Correlation radiometers make true differential measurements in power with high accuracy and small systematic errors. This receiver architecture has been used in radio astronomy for measurements of continuum radiation for over 50 years; this article examines ... More
Effects of an impermeable wall in dissipative dynamics of saturated porous mediaFeb 27 2016A phase transition model for porous media in consolidation is studied. The model is able to describe the phenomenon of fluid-segregation during the consolidation process, i.e., the coexistence of two phases differing from fluid content inside the porous ... More
A lower bound for the a.e. behaviour of Hausdorff dimension under vertical projections in the Heisenberg groupNov 30 2018Dec 07 2018It is shown that for a Borel set $A$ in the Heisenberg group with $\dim A >2$, \[ \dim P_{\mathbb{V}^{\perp}_{\theta}} A \geq \begin{cases} \frac{\dim A}{2} &\text{ if } \dim A \in \left(2, \frac{5}{2} \right] \\ \frac{ \dim A(\dim A + 2)}{4\dim A -1} ... More
Improved decay of conical averages of the Fourier transformJun 21 2018Jan 18 2019An improved lower bound is given for the decay of conical averages of Fourier transforms of measures, in dimensions $d \geq 4$. The proof uses a weighted version of the broad restriction inequality, a narrow decoupling inequality for the cone, and some ... More
Refined Strichartz inequalities for the wave equationMay 18 2018Jun 08 2018Some analogues of the Schr\"odinger refined Strichartz inequalities (Du, Guth, Li and Zhang) are obtained for the wave equation. These are used to improve the best known $L^2$ fractal Strichartz inequalities for the wave equation in dimensions $d \geq ... More
Static- and Stationary-complete Spacetimes: Algebraic and Causal StructuresDec 24 2014Jun 05 2015This is intended as an analysis of the global properties of static and stationary spacetimes with complete (timelike) Killing field, with particular attention to quotients by group actions. This is presented in terms of algebraic structures which are ... More
Modelling the application of integrated photonic spectrographs to astronomyJul 23 2012One of the well-known problems of producing instruments for Extremely Large Telescopes is that their size (and hence cost) scales rapidly with telescope aperture. To try to break this relation alternative new technologies have been proposed, such as the ... More
Disordered asymmetric simple exclusion process: mean-field treatmentMar 01 2004We provide two complementary approaches to the treatment of disorder in a fundamental nonequilibrium model, the asymmetric simple exclusion process. Firstly, a mean-field steady state mapping is generalized to the disordered case, where it provides a ... More
The Chandra Survey of Extragalactic Sources in the 3CR Catalog: X-ray Emission from Nuclei, Jets, and Hotspots in the Chandra Archival ObservationsSep 22 2016As part of our program to build a complete radio and X-ray database of all the 3CR extragalactic radio sources, we present an analysis of 93 sources for which Chandra archival data are available. Most of these sources have been already published. Here ... More
Photonic spatial reformatting of stellar light for diffraction-limited spectroscopyFeb 11 2014Jun 08 2015The spectral resolution of a dispersive spectrograph is dependent on the width of the entrance slit. This means that astronomical spectrographs trade-off throughput with spectral resolving power. Recently, optical guided-wave transitions known as photonic ... More
Scaling approach to related disordered stochastic and free-fermion modelsJun 23 2006Jan 03 2007Motivated by mapping from a stochastic system with spatially random rates, we consider disordered non-conserving free-fermion systems using a scaling procedure for the equations of motion. This approach demonstrates disorder-induced localization acting ... More
On-off Threshold Models of Social ContagionSep 10 2012We study binary state contagion dynamics on a social network where nodes act in response to the average state of their neighborhood. We model the competing tendencies of imitation and non-conformity by incorporating an off-threshold into standard threshold ... More
Symmetry Analysis of Multiferroic Co_3TeO_6Feb 16 2012A phenomenological explanation of the magnetoelectric behavior of Co_3TeO_6 is developed. We explain the second harmonic generation data and the magnetic field induced spontaneous polarization in the magnetically ordered phase below 20K.
Universality of the Future Chronological BoundaryApr 04 1997Sep 26 1997The purpose of this note is to establish, in a categorical manner, the universality of the Geroch-Kronheimer-Penrose causal boundary when considering the types of causal structures that may profitably be put on any sort of boundary for a spacetime. Actually, ... More
Electromagnetically Induced Transparency and Quantum Heat EnginesNov 03 2016We describe how electromagnetically induced transparency may be used to construct a non-traditional near-ideal quantum heat engine as constrained by the Second Law. The engine is pumped by a thermal reservoir that may be either hotter or colder than that ... More
Branching Brownian motion: Almost sure growth along unscaled pathsNov 11 2008We give new results on the growth of the number of particles in a dyadic branching Brownian motion which follow within a fixed distance of a path $f:[0,\infty)\to \mathbb{R}$. We show that it is possible to count the number of particles without rescaling ... More
Nonlocal Modulation of Entangled PhotonsAug 06 2008We consider ramifications of the use of high speed light modulators to questions of correlation and measurement of time-energy entangled photons. Using phase modulators, we find that temporal modulation of one photon of an entangled pair, as measured ... More
Topology of the Future Chronological Boundary: Universality for Spacelike BoundariesJul 19 1999Nov 10 1999A method is presented for imputing a topology for any chronological set, i.e., a set with a chronology relation, such as a spacetime or a spacetime with some sort of boundary. This topology is shown to have several good properties, such as replicating ... More
Error-prone polymerase activity causes multinucleotide mutations in humansDec 05 2013Apr 29 2014About 2% of human genetic polymorphisms have been hypothesized to arise via multinucleotide mutations (MNMs), complex events that generate SNPs at multiple sites in a single generation. MNMs have the potential to accelerate the pace at which single genes ... More
Powers of Ideals and Fibers of MorphismsJul 26 2008Let X\subset PP^n be a projective scheme over a field, and let phi:X --> Y be a finite morphism. Our main result is a formula in terms of global data for the maximum of the Castelnuovo-Mumford regularity of the fibers of \phi, considered as subschemes ... More
The Chern-Mather class of the multiview varietyJan 24 2017The multiview variety associated to a collection of $N$ cameras records which sequences of image points in $\mathbb{P}^{2N}$ can be obtained by taking pictures of a given world point $x\in\mathbb{P}^3$ with the cameras. In order to reconstruct a scene ... More
Fluctuation theorems for stochastic dynamicsFeb 23 2007Aug 02 2007Fluctuation theorems make use of time reversal to make predictions about entropy production in many-body systems far from thermal equilibrium. Here we review the wide variety of distinct, but interconnected, relations that have been derived and investigated ... More
First-order phase transitions from poles in asymptotic representations of partition functionsDec 18 2009Mar 26 2010Although partition functions of finite-size systems are always analytic, and hence have no poles, they can be expressed in many cases as series containing terms with poles. Here we show that such poles can be related to linear branches of the entropy, ... More
Generalized Thermal Lattice GasesMay 07 1998We show how to employ thermal lattice gas models to describe non-equilibrium phenomena. This is achieved by relaxing the restrictions of the usual micro-canonical ensemble for these models via the introduction of thermal ``demons'' in the style of Creutz. ... More
A combinatorial model for computing volumes of flow polytopesJan 23 2018We introduce new families of combinatorial objects whose enumeration computes volumes of flow polytopes. These objects provide an interpretation, based on parking functions, of Baldoni and Vergne's generalization of a volume formula originally due to ... More
Reanalysis of the EMC charm production data with extrinsic and intrinsic charm at NLOAug 30 1995Dec 07 1995A calculation of the next-to-leading order exclusive extrinsic charm quark differential distributions in deeply inelastic electroproduction has recently been completed. Using these results we compare the NLO extrinsic contributions to the charm structure ... More
Double epitaxy of tetragonal and hexagonal phases in the FeSe systemFeb 09 2019Epitaxial films which contains more than one crystallographic orientation are of interest due to the possibility of altered magnetic, electrical, and optical properties. Thin films of FeSe have been grown on single-crystal MgO substrates under conditions ... More
Spectrophotometry of the Huygens Region of the Orion Nebula, the Extended Orion Nebula, and M~43; Scattered Light Systematically Distorts Conditions Derived from Emission-LinesAug 05 2010We report on medium resolution spectrophotometry of the Orion Nebula region, including for the first time the Extended Orion Nebula and the nearby M~43. The 49 long slit observations were divided into 99 smaller samples, which have allowed determinations ... More
Optimizing astrophotonic spatial reformatters using simulated on-sky performanceJul 17 2018One of the most useful techniques in astronomical instrumentation is image slicing. It enables a spectrograph to have a more compact angular slit, whilst retaining throughput and increasing resolving power. Astrophotonic components like the photonic lanterns ... More
Hydrodynamics of the zero-range process in the condensation regimeAug 09 2006Dec 11 2006We argue that the coarse-grained dynamics of the zero-range process in the condensation regime can be described by an extension of the standard hydrodynamic equation obtained from Eulerian scaling even though the system is not locally stationary. Our ... More
A thorough view of the nuclear region of NGC 253 - Combined Herschel, SOFIA and APEX datasetApr 29 2018Jun 12 2018We present a large set of spectral lines detected in the $40"$ central region of the starburst galaxy NGC 253. Observations were obtained with the three instruments SPIRE, PACS and HIFI on board the Herschel Space Observatory, upGREAT on board of the ... More
Dealing with Uncertainties in Asteroid Deflection Demonstration Missions: NEOTwISTJan 09 2016Feb 04 2016Deflection missions to near-Earth asteroids will encounter non-negligible uncertainties in the physical and orbital parameters of the target object. In order to reliably assess future impact threat mitigation operations such uncertainties have to be quantified ... More
Swift observations of unidentified radio sources in the revised Third Cambridge CatalogueSep 23 2016We have investigated a group of unassociated radio sources included in the 3CR cat- alogue to increase the multi-frequency information on them and possibly obtain an identification. We have carried out an observational campaign with the Swift satellite ... More
Astronomical photonics in the context of infrared interferometry and high-resolution spectroscopyAug 08 2016We review the potential of Astrophotonics, a relatively young field at the interface between photonics and astronomical instrumentation, for spectro-interferometry. We review some fundamental aspects of photonic science that drove the emer- gence of astrophotonics, ... More
Model Atmosphere Analysis of the Weakly Magnetic DZ White Dwarf G165-7Aug 02 2006A reanalysis of the strongly metal-blanketed DZ white dwarf G165-7 is presented. An improved grid of model atmospheres and synthetic spectra is used to analyze BVRI, JHK, and ugriz photometric observations as well as a high quality Sloan Digital Sky Survey ... More
Brownian walkers within subdiffusing territorial boundariesFeb 04 2011Jun 01 2011Inspired by the collective phenomenon of territorial emergence, whereby animals move and interact through the scent marks they deposit, we study the dynamics of a 1D Brownian walker in a random environment consisting of confining boundaries that are themselves ... More
Traffic of cytoskeletal motors with disordered attachment ratesJun 24 2008Feb 19 2010Motivated by experimental results on the interplay between molecular motors and tau proteins, we extend lattice-based models of intracellular transport to include a second species of particle which locally influences the motor-filament attachment rate. ... More
Hydrodynamic behaviour of Lattice Boltzmann and Lattice BGK modelsAug 30 1993We present a numerical analysis of the validity of classical and generalized hydrodynamics for Lattice Boltzmann Equation (LBE) and Lattice BGK methods in two and three dimensions, as a function of the collision parameters of these models. Our analysis ... More
On the Spectral Evolution of Cool, Helium-Atmosphere White Dwarfs: Detailed Spectroscopic and Photometric Analysis of DZ StarsMar 29 2007We present a detailed analysis of a large spectroscopic and photometric sample of DZ white dwarfs based on our latest model atmosphere calculations. We revise the atmospheric parameters of the trigonometric parallax sample of Bergeron, Leggett, & Ruiz ... More
Generation and Application of Bessel Beams in Electron MicroscopyMay 28 2015We report a systematic treatment of the holographic generation of electron Bessel beams, with a view to applications in electron microscopy. We describe in detail the theory underlying hologram patterning, as well as the actual electro-optical configuration ... More
Enhanced Tunnelling in a Hybrid of Single-Walled Carbon Nanotubes and GrapheneMar 15 2019Transparent and conductive films (TCFs) are of great technological importance. The high transmittance, electrical conductivity and mechanical strength make single-walled carbon nanotubes (SWCNTs) a good candidate for their raw material. Despite the ballistic ... More
Thermodynamic uncertainty for run-and-tumble type processesMar 05 2019Thermodynamic uncertainty relations have emerged as universal bounds on current fluctuations in non-equilibrium systems. Here we derive a new bound for a particular class of run-and-tumble type processes using the mathematical framework of renewal-reward ... More
A Color-Magnitude Diagram for a Globular Cluster In the Giant Elliptical Galaxy NGC 5128Jun 30 1998The Hubble Space Telescope has been used to obtain WFPC2 (V,I) photometry for a large sample of stars in the outer halo of the giant elliptical NGC 5128 (d = 4 Mpc). The globular cluster N5128-C44, at the center of the Planetary Camera field, is well ... More
Exponential growth rates in a typed branching diffusionApr 03 2007We study the high temperature phase of a family of typed branching diffusions initially studied in [Ast\'{e}risque 236 (1996) 133--154] and [Lecture Notes in Math. 1729 (2000) 239--256 Springer, Berlin]. The primary aim is to establish some almost-sure ... More
The 3CR $Chandra$ extragalactic survey at 1.0$<z<$1.5Jun 28 2018The aim of this paper is to present an analysis of newly acquired X-ray observations of 16 extragalactic radio sources, listed in the Third Cambridge Revised (3CR) catalog, and not previously observed by Chandra. Observations were performed during Chandra ... More
Defect production in quench from current-carrying non-equilibrium stateAug 31 2015Mar 28 2016We consider the defect production of a quantum system, initially prepared in a current-carrying non-equilibrium state, during its unitary driving through a quantum critical point. At low values of the initial current, the quantum Kibble-Zurek scaling ... More