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Non-LTE Effects of Na I in the Atmosphere of HD209458bMar 08 2002The recent announcement that sodium absorption has been observed in the atmosphere of HD209458b, the only EGP observed to transit its parent star, is the first direct detection of an EGP atmosphere. We explore the possibility that neutral sodium is {\em ... More

Signal reconstruction in linear mixing systems with different error metricsFeb 02 2013We consider the problem of reconstructing a signal from noisy measurements in linear mixing systems. The reconstruction performance is usually quantified by standard error metrics such as squared error, whereas we consider any additive error metric. Under ... More

Black hole mass estimation for Active Galactic Nuclei from a new angleMar 05 2019The scaling relations between supermassive black holes and their host galaxy properties are of fundamental importance in the context black hole-host galaxy co-evolution throughout cosmic time. In this work, we use a novel algorithm that identifies smooth ... More

Quantitative Photospheric Spectral Analysis of the Type IIP Supernova 2007odFeb 03 2012We compare and analyze a time series of spectral observations obtained during the first 30 days of evolution of SN 2007od with the non-LTE code PHOENIX. Despite some spectroscopic particularities in the Balmer features, this supernova appears to be a ... More

Synthetic Spectra from 3D Models of SupernovaeJul 03 2002We describe Brute, a code for generating synthetic spectra from 3D supernova models. It is based on a Monte Carlo implementation of the Sobolev approximation. The current version is highly parameterized, but in the future it will be extended for full ... More

Sojourn times and fixation dynamics in multi-player games with fluctuating environmentsDec 16 2016We study evolutionary multi-player games in finite populations, subject to fluctuating environments. The population undergoes a birth-death process with absorbing states, and the environment follows a Markovian process, resulting in a fluctuating payoff ... More

A 3D radiative transfer framework: XI. multi-level NLTEApr 16 2014Multi-level non-local thermodynamic equilibrium (NLTE) radiation transfer calculations have become standard throughout the stellar atmospheres community and are applied to all types of stars as well as dynamical systems such as novae and supernovae. Even ... More

Co-moving frame radiative transfer in spherical media with arbitrary velocity fieldsAug 11 2004Recently, with the advances in computational speed and availability there has been a growth in the number and resolution of fully 3-D hydrodynamical simulations. However, all of these simulations are purely hydrodynamical and there has been little attempt ... More

Non-LTE Treatment of Fe II in Astrophysical PlasmasJan 25 1996We describe our implementation of an extremely detailed model atom of singly ionized iron for NLTE computations in static and moving astrophysical plasmas. Our model atom includes 617 levels, 13675 primary permitted transitions and up to 1.2 million secondary ... More

Inclination-Dependent AGN Flux Profiles From Strong Lensing of the Kerr Space-TimeNov 12 2012Recent quasar microlensing observations have constrained the X-ray emission sizes of quasars to be about 10 gravitational radii, one order of magnitude smaller than the optical emission sizes. Using a new ray-tracing code for the Kerr space-time, we find ... More

Wiener Filters in Gaussian Mixture Signal Estimation with Infinity-Norm ErrorMay 17 2014Jul 26 2014Consider the estimation of a signal ${\bf x}\in\mathbb{R}^N$ from noisy observations ${\bf r=x+z}$, where the input~${\bf x}$ is generated by an independent and identically distributed (i.i.d.) Gaussian mixture source, and ${\bf z}$ is additive white ... More

General Relativistic Radiative TransferNov 30 2006We present a general method to calculate radiative transfer including scattering in the continuum as well as in lines in spherically symmetric systems that are influenced by the effects of general relativity (GR). We utilize a comoving wavelength ansatz ... More

Parallelization Strategies for ALI Radiative Transfer in Moving MediaJul 01 2002We describe the method we have used to parallelize our spherically symmetric special relativistic short characteristics general radiative transfer code PHOENIX. We describe some possible parallelization strategies and show why they would be inefficient. ... More

The NextGen Model Atmosphere grid for $3000\le \Teff \le 10000\K$Jul 28 1998We present our NextGen Model Atmosphere grid for low mass stars for effective temperatures larger than $3000\K$. These LTE models are calculated with the same basic model assumptions and input physics as the VLMS part of the NextGen grid so that the complete ... More

NLTE Modeling of SNe Ia Near Maximum LightNov 17 1995Modeling the atmospheres of SNe~Ia requires the solution of the NLTE radiative transfer equation. We discuss the formulation of the radiative transfer equation in the co-moving frame. For characteristic velocities larger than about 2000 km/s, the effects ... More

Parallel Implementation of the PHOENIX Generalized Stellar Atmosphere ProgramJul 17 1996Jan 21 1997We describe the parallel implementation of our generalized stellar atmosphere and NLTE radiative transfer computer program PHOENIX. We discuss the parallel algorithms we have developed for radiative transfer, spectral line opacity, and NLTE opacity and ... More

Compressive Imaging via Approximate Message Passing with Image DenoisingMay 17 2014Feb 13 2015We consider compressive imaging problems, where images are reconstructed from a reduced number of linear measurements. Our objective is to improve over existing compressive imaging algorithms in terms of both reconstruction error and runtime. To pursue ... More

Mixture Gaussian Signal Estimation with L_infty Error MetricApr 22 2013We consider the problem of estimating an input signal from noisy measurements in both parallel scalar Gaussian channels and linear mixing systems. The performance of the estimation process is quantified by the $\ell_\infty$ norm error metric. We first ... More

The Spectrum of the FeLoBAL Quasar FBQS 1214+2803: A Resonance-Scattering InterpretationAug 28 2002The usual interpetation of the spectrum of a BAL QSO is that a broad-band continuum from the central engine plus broad emission lines from a surrounding region (the BELR) emerges from near the center of the QSO, and broad absorption lines are superimposed ... More

Massive Multi-species, Multi-level NLTE Model Atmospheres for Novae in OutburstJun 14 1999We have used our PHOENIX multi-purpose model atmosphere code to calculate atmospheric models that represent novae in the optically thick wind phases of their outburst. We have improved the treatment of NLTE effects by expanding the number of elements ... More

Non-LTE Modeling of Nova Cygni 1992Sep 29 2000We present a grid of nova models that have an extremely large number of species treated in non-LTE, and apply it to the analysis of an extensive time series of ultraviolet spectroscopic data for Nova Cygni 1992. We use ultraviolet colors to derive the ... More

Spectral Consequences of Deviation from Spherical Composition Symmetry in Type Ia SupernovaeJul 24 2001We investigate the prospects for constraining the maximum scale of clumping in composition that is consistent with observed Type Ia supernova flux spectra. Synthetic spectra generated without purely spherical composition symmetry indicate that gross asymmetries ... More

SNe Ia: Can Chandrasekhar Mass Explosions Reproduce the Observed Zoo?Aug 18 2014The question of the nature of the progenitor of Type Ia supernovae (SNe Ia) is important both for our detailed understanding of stellar evolution and for their use as cosmological probes of the dark energy. Much of the basic features of SNe Ia can be ... More

Multi-Processor Approximate Message Passing Using Lossy CompressionJan 18 2016In this paper, a communication-efficient multi-processor compressed sensing framework based on the approximate message passing algorithm is proposed. We perform lossy compression on the data being communicated between processors, resulting in a reduction ... More

Type IIP Supernovae as Cosmological Probes: A SEAM Distance to SN 1999emOct 06 2004Due to their intrinsic brightness, supernovae make excellent cosmological probes. We describe the SEAM method for obtaining distances to Type IIP supernovae (SNe IIP) and present a distance to SN 1999em for which a Cepheid distance exists. Our models ... More

A 3D radiative transfer framework: VII. Arbitrary velocity fields in the Eulerian frameJul 20 2010A solution of the radiative-transfer problem in 3D with arbitrary velocity fields in the Eulerian frame is presented. The method is implemented in our 3D radiative transfer framework and used in the PHOENIX/3D code. It is tested by comparison to our well- ... More

NLTE Effects in Modeling of Supernovae near Maximum LightMay 15 1996Supernovae, with their diversity of compositions, velocities, envelope masses, and interactions are good testing grounds for probing the importance of NLTE in expanding atmospheres. In addition to treating H, He, Li I, O I, Ne I, Na I, and Mg II in NLTE, ... More

Carnegie Supernova Project-II: Using Near-Infrared Spectroscopy to determine the location of the outer $^{56}$Ni in Type Ia SupernovaeFeb 26 2019We present the $H$-band wavelength region of thirty post-maximum light near-infrared (NIR) spectra of fourteen transitional and sub-luminous type Ia supernovae (SNe Ia), extending from $+$5d to +20d relative to the epoch of $B$-band maximum. We introduce ... More

Early and late time VLT spectroscopy of SN 2001el - progenitor constraints for a type Ia supernovaJan 20 2005Oct 13 2005We present early time high-resolution (VLT/UVES) and late time low-resolution (VLT/FORS) optical spectra of the normal type Ia supernova, SN 2001el. The high-resolution spectra were obtained at -9 and -2 days to allow the detection of narrow hydrogen ... More

A binary engine fuelling HD87643' s complex circumstellar environment, using AMBER/VLTIAug 03 2009Sep 22 2009Context. The star HD 87643, exhibiting the "B[e] phenomenon", has one of the most extreme infrared excesses for this object class. It harbours a large amount of both hot and cold dust, and is surrounded by an extended reflection nebula. Aims. One of our ... More

Order of Magnitude Smaller Limit on the Electric Dipole Moment of the ElectronOct 28 2013Nov 07 2013The Standard Model (SM) of particle physics fails to explain dark matter and why matter survived annihilation with antimatter following the Big Bang. Extensions to the SM, such as weak-scale Supersymmetry, may explain one or both of these phenomena by ... More

Spectral Modeling of Type II SupernovaeNov 17 2006Using models of the SN~IIP 2005cs, we show that detailed spectral analysis can be used to determine reddening and abundances.

Approximate Message Passing in Coded Aperture Snapshot Spectral ImagingSep 08 2015We consider a compressive hyperspectral imaging reconstruction problem, where three-dimensional spatio-spectral information about a scene is sensed by a coded aperture snapshot spectral imager (CASSI). The approximate message passing (AMP) framework is ... More

Effects of Kerr Strong Gravity on Quasar X-ray MicrolensingNov 28 2012Recent quasar microlensing observations have constrained the sizes of X-ray emission regions to be within about 10 gravitational radii of the central supermassive black hole. Therefore, the X-ray emission from lensed quasars is first strongly lensed by ... More

A 3D radiative transfer framework: X. Arbitrary Velocity Fields in the Co-moving FrameOct 24 2012Nov 07 20123-D astrophysical atmospheres will have random velocity fields. We seek to combine the methods we have developed for solving the 1-D problem with arbitrary flows to those that we have developed for solving the fully 3-D relativistic radiative transfer ... More

Stellar Population Models and Individual Element Abundances I: Sensitivity of Stellar Evolution ModelsJun 06 2007Integrated light from distant galaxies is often compared to stellar population models via the equivalent widths of spectral features--spectral indices--whose strengths rely on the abundances of one or more elements. Such comparisons hinge not only on ... More

Evidence for AGN Feedback in the Broad Absorption Lines and Reddening of Mrk 231Apr 27 2014May 03 2014We present the first J-band spectrum of Mrk 231, which reveals a large \ion{He}{1}*$\lambda 10830$ broad absorption line with a profile similar to that of the well-known \ion{Na}{1} broad absorption line. Combining this spectrum with optical and UV spectra ... More

On the Origin of Planetary Nebula K648 in Globular Cluster M15Jul 10 1997We examine two scenarios for formation of the planetary nebula K648: a prompt scenario where the planetary nebula is ejected and formed immediately after a helium shell flash and a delayed scenario where a third dredge up occurs and the envelope is ejected ... More

On the Geometry of the High-Velocity Ejecta of the Peculiar Type Ia Supernova 2000cxFeb 13 2003Oct 14 2003High-velocity features in Type Ia supernova spectra provide a way to probe the outer layers of these explosions. The maximum-light spectra of the unique Type Ia supernova 2000cx exhibit interesting Ca II features with high-velocity components. The infrared ... More

Supernova Resonance--scattering Line Profiles in the Absence of a PhotosphereSep 16 2012In supernova spectroscopy relatively little attention has been given to the properties of optically thick spectral lines in epochs following the photosphere's recession. Most treatments and analyses of post-photospheric optical spectra of supernovae assume ... More

The low-lying baryon spectrum with two dynamical twisted mass fermionsOct 13 2009The masses of the low lying baryons are evaluated using two degenerate flavors of twisted mass sea quarks corresponding to pseudo scalar masses in the range of about 270-500 MeV. The strange valence quark mass is tuned to reproduce the mass of the kaon ... More

Reading the Spectra of the Most Peculiar Type Ia Supernova 2002cxAug 06 2004In spite of the apparent lack of Si II and S II features in its spectra, SN 2002cx was classified as a peculiar Type Ia supernova (SN Ia) on the basis of its overall photometric and spectroscopic behavior. Spectra obtained near maximum light contained ... More

A Comparative Study of the Absolute-Magnitude Distributions of SupernovaeDec 04 2001The Asiago Supernova Catalog is used to carry out a comparative study of supernova absolute-magnitude distributions. An overview of the absolute magnitudes of the supernovae in the current observational sample is presented, and the evidence for subluminous ... More

3D density structure and geological evolution of Stromboli volcano (Aeolian Islands, Italy) inferred from land-based and marine gravity dataJan 06 2017We present the first density model of Stromboli volcano (Aeolian Islands, Italy) obtained by simultaneously inverting land-based (543) and sea-surface (327) relative gravity data. Modern positioning technology, a 1 * 1 m digital elevation model, and a ... More

JWST: Probing the Epoch of Reionization with a Wide Field Time-Domain SurveyMar 13 2019A major scientific goal of JWST is to probe the epoch of re-ionization of the Universe at z above 6, and up to 20 and beyond. At these redshifts, galaxies are just beginning to form and the observable objects are early black holes, supernovae, and cosmic ... More

Introduction to High-Resolution Inelastic X-Ray ScatteringApr 05 2015May 18 2015This paper reviews non-resonant, meV-resolution inelastic x-ray scattering (IXS), as applied to the measurement of atomic dynamics of crystalline materials. It is designed to be an introductory, though in-depth, look at the field for those who may interested ... More

Interpretable Machine Learning for Privacy-Preserving Pervasive SystemsOct 23 2017Jun 13 2018The presence of pervasive systems in our everyday lives and the interaction of users with connected devices such as smartphones or home appliances generate increasing amounts of traces that reflect users' behavior. A plethora of machine learning techniques ... More

Accelerating gravitational microlensing simulations using the Xeon Phi coprocessorMar 28 2017Recently Graphics Processing Units (GPUs) have been used to speed up very CPU-intensive gravitational microlensing simulations. In this work, we use the Xeon Phi coprocessor to accelerate such simulations and compare its performance on a microlensing ... More

SPARQL as a Foreign LanguageAug 25 2017In the last years, the Linked Data Cloud has achieved a size of more than 100 billion facts pertaining to a multitude of domains. However, accessing this information has been significantly challenging for lay users. Approaches to problems such as Question ... More

Near-infrared line identification in type Ia supernovae during the transitional phaseJul 29 2014We present near-infrared synthetic spectra of a delayed-detonation hydrodynamical model and compare them to observed spectra of four normal type Ia supernovae ranging from day +56.5 to day +85. This is the epoch during which supernovae are believed to ... More

Small-N collisional dynamics III: The battle for the realm of not-so-small-NJul 06 2017In this paper, the third in the series, we continue our study of combinatorics in chaotic Newtonian dynamics. We study the chaotic four-body problem in Newtonian gravity assuming finite-sized particles, and we focus on interactions that produce direct ... More

Phonons in Crystals using Inelastic X-Ray ScatteringOct 30 2009The use of inelastic x-ray scattering (IXS) to investigate phonons and phonon dispersion in crystals opens the field of phonon spectroscopy, allowing measurements on tiny samples: micrograms of material, or single crystals ~10 to 100 micron diameter are ... More

Collective coordinate approximation to the scattering of solitons in modified NLS and sine-Gordon modelsNov 13 2014Nov 02 2015We investigate the validity of collective coordinate approaximations to the scattering of solitons in several classes of models in (1+1) dimensional field theory models. We look at models which are deformations of the sine-Gordon (SG) or the nonlinear ... More

Steps for Solving the Transfer Equation for Arbitrary Flows in Stationary SpacetimesMar 09 2006Feb 21 2007We derive the radiative transfer equation for arbitrary stationary relativistic flows in stationary spacetimes, i.e. for steady-state transfer problems. We show how the standard characteristics method of solution developed by Mihalas and used throughout ... More

Multi-Processor Approximate Message Passing with Lossy CompressionJan 15 2016We consider large-scale linear inverse problems in Bayesian settings. Our general approach follows a recent line of work that applies the approximate message passing (AMP) framework in multi-processor (MP) computational systems by storing and processing ... More

A Universal Parallel Two-Pass MDL Context Tree Compression AlgorithmJul 06 2014Mar 21 2015Computing problems that handle large amounts of data necessitate the use of lossless data compression for efficient storage and transmission. We present a novel lossless universal data compression algorithm that uses parallel computational units to increase ... More

The weirdest SDSS galaxies: results from an outlier detection algorithmNov 22 2016How can we discover objects we did not know existed within the large datasets that now abound in astronomy? We present an outlier detection algorithm that we developed, based on an unsupervised Random Forest. We test the algorithm on more than two million ... More

Measurement of the $4\: S_{1/2} \rightarrow 6 \: S_{1/2}$ transition frequency in atomic potassium via direct frequency comb spectroscopyJun 09 2017We present an experimental determination of the $4 \: S_{1/2} \rightarrow 6\: S_{1/2}$ transition frequency in atomic potassium, $^{39}$K, using direct frequency comb spectroscopy. The output of a stabilized optical frequency comb was used to excite a ... More

Nucleon form factors with Nf=2 dynamical twisted mass fermionsOct 19 2009Oct 22 2009We present results on the electromagnetic and axial nucleon form factors using two degenerate flavors of twisted mass fermions on lattices of spatial size 2.1 fm and 2.7 fm and a lattice spacing of about 0.09 fm. We consider pion masses in the range of ... More

Discovery of a Circumbinary Disk around Herbig Ae/Be system v892 TauJul 01 2008We report the discovery of a circumbinary disk around the Herbig Ae/Be system v892 Tau. Our detailed mid-infrared images were made using segment-tilting interferometry on the Keck-1 Telescope and reveal an asymmetric disk inclined at ~60 degs with an ... More

Metallicity Effects in NLTE Model Atmospheres of Type Ia SupernovaeJun 01 1999Sep 03 1999We have calculated a grid of photospheric phase atmospheres of Type Ia supernovae (SNe Ia) with metallicities from ten times to one thirtieth the solar metallicity in the C+O layer of the deflagration model, W7. We have modeled the spectra using the multi-purpose ... More

Detailed NLTE Model Atmospheres for Novae during Outburst: I. New Theoretical ResultsJul 08 1997We present new detailed NLTE calculations for model atmospheres of novae during outburst. This fully self-consistent NLTE treatment for a number of model atoms includes 3922 NLTE levels and 47061 NLTE primary transitions. We discuss the implication of ... More

Non-LTE model atmosphere analysis of the early ultraviolet spectra of nova OS Andromedae 1986Aug 29 1996We have analyzed the early optically thick ultraviolet spectra of Nova OS And 1986 using a grid of spherically symmetric, non-LTE, line-blanketed, expanding model atmospheres and synthetic spectra with the following set of parameters: $5,000\le$ T$_{model}$ ... More

Characterization of self-phase modulation in liquid filled hollow core photonic band gap fibersJul 23 2010We experimentally and theoretically study self-phase modulation by Kerr effect in a liquid filled hollow core photonic crystal fiber. We perform a complete characterization of the linear optical properties of the hollow core photonic band gap fiber filled ... More

Strings and D-branes in curved space-timeNov 08 2012In this thesis we study the AdS3 Wess-Zumino-Novikov-Witten model. We compute the Operator Product Expansion of primary fields as well as their images under the spectral flow automorphism in all sectors of the model by considering it as a Wick rotation ... More

Comparative Analysis of Peculiar Type Ia 1991bg-like Supernovae SpectraMay 17 2011Spectroscopic analyses of Type Ia supernovae have shown there exist four spectroscopic groups---cools, broad line, shallow silicon, and core normal---defined by the widths of the Si II features at 5972 Angstroms and 6355 Angstroms. 1991bg-likes are classified ... More

A graphical extension for the Windows version of the Parallel Finite Element Micromagnetics Package (MagParExt)Jul 16 2008In the current paper we present a graphical user interface useful for settings input parameter of the Windows precompiled binaries for the Parallel Finite Element Micromagnetics Package (MagPar). The Package is used for magnetization dynamics analysis ... More

Uplifting Maximal Gauged SupergravitiesDec 17 2015Which theories have a higher dimensional origin in String/M-theory is a non trivial question and it is still far from being understood in the constrained scenario of maximal supergravities. After 35 years of progress in this direction we have found supporting ... More

Lipschitzian solutions to inhomogeneous linear iterative equationsJul 01 2016We study the problems of the existence, uniqueness and continuous dependence of Lipschitzian solutions $\varphi$ of equations of the form $$ \varphi(x)=\int_{\Omega}g(\omega)\varphi\big(f(x,\omega)\big)\mu(d\omega)+F(x), $$ where $\mu$ is a measure on ... More

Fringe tracking and spatial filtering: phase jumps and dropoutsJul 12 2008Fringe tracking in interferometers is typically analyzed with the implicit assumption that there is a single phase associated with each telescope in the array. If the telescopes have apertures significantly larger than r0 and only partial adaptive optics ... More

Carnegie Supernova Project-II: The Near-infrared Spectroscopy ProgramOct 18 2018Dec 03 2018Shifting the focus of Type Ia supernova (SN Ia) cosmology to the near-infrared (NIR) is a promising way to significantly reduce the systematic errors, as the strategy minimizes our reliance on the empirical width-luminosity relation and uncertain dust ... More

Nickel Mixing in the Outer Layers of SN 1987AApr 09 2001Supernova 1987A remains the most well-observed and well-studied supernova to date. Observations produced excellent broad-band photometric and spectroscopic coverage over a wide wavelength range at all epochs. Here, we focus on the very early spectroscopic ... More

Optical Spectra of the Type Ia Supernova 1998aqMay 18 2003We present 29 optical spectra of the normal Type Ia SN 1998aq, ranging from 9 days before to 241 days after the time of maximum brightness. This spectroscopic data set, together with photometric data presented elsewhere, makes SN 1998aq one of the best ... More

Demonstration of nonstoquastic Hamiltonian in coupled superconducting flux qubitsMar 14 2019Quantum annealing (QA) is a heuristic algorithm for finding low-energy configurations of a system, with applications in optimization, machine learning, and quantum simulation. Up to now, all implementations of QA have been limited to qubits coupled via ... More

Searching for Hydrogen in Type Ib SupernovaeJun 07 2010We present synthetic spectral fits of the typical Type Ib SN 1999dn and the Hydrogen Rich Ib SN 2000H using the generalized non-local thermodynamic equilibrium stellar atmospheres code \phx. We fit model spectra to five epochs of SN 1999dn ranging from ... More

Gaugings from E7 Extended GeometriesApr 30 2014We discuss the construction of gaugings in recent models of E7 Extended Geometries, focusing on the two inequivalent SL(8) truncations of the theory. In these sectors the conditions for the generation of gaugings in the 36, 36', 420 and 420' representations ... More

Hypergraph Acyclicity RevisitedMar 27 2014The notion of graph acyclicity has been extended to several different notions of hypergraph acyclicity, in increasing order of generality: gamma acyclicity, beta acyclicity, and alpha acyclicity, that have met a great interest in many fields. We prove ... More

Performance Regions in Compressed Sensing from Noisy MeasurementsFeb 18 2013In this paper, compressed sensing with noisy measurements is addressed. The theoretically optimal reconstruction error is studied by evaluating Tanaka's equation. The main contribution is to show that in several regions, which have different measurement ... More

On modular properties of the AdS3 CFTDec 10 2010We study modular properties of the AdS3 WZNW model. Although the Euclidean partition function is modular invariant, the characters on the Euclidean torus are ill-defined and their modular transformations are unknown. We reconsider the characters defined ... More

The Odd story of $α'$-correctionsFeb 17 2017The $\alpha'$-deformed frame-like Double Field Theory (DFT) is a T-duality and gauge invariant extension of DFT in which generalized Green-Schwarz transformations provide a gauge principle that fixes the higher-derivative corrections. It includes all ... More

Implementing SCRUM to develop a connected robotJul 03 2018Agile methods are receiving a growing interest from industry and these approaches are nowadays well accepted and deployed in software engineering. However, some issues remain to introduce agility in systems engineering. The objective of this paper is ... More

Stellar Population Models and Individual Element Abundances II: Stellar Spectra and Integrated Light ModelsDec 08 2008Dec 22 2008The first paper in this series explored the effects of altering the chemical mixture of the stellar population on an element by element basis on stellar evolutionary tracks and isochrones to the end of the red giant branch. This paper extends the discussion ... More

A 3D radiative transfer framework: VI. PHOENIX/3D example applicationsNov 17 2009Nov 20 2009We demonstrate the application of our 3D radiative transfer framework in the model atmosphere code PHOENIX/3D for a number of spectrum synthesis calculations for very different conditions. The 3DRT framework discussed in the previous papers of this series ... More

Parallel Implementation of the PHOENIX Generalized Stellar Atmosphere Program. II: Wavelength ParallelizationSep 24 1997We describe an important addition to the parallel implementation of our generalized NLTE stellar atmosphere and radiative transfer computer program PHOENIX. In a previous paper in this series we described data and task parallel algorithms we have developed ... More

Stochastic fluctuations and quasi-pattern formation in reaction-diffusion systems with anomalous transportDec 09 2018Jan 20 2019Many approaches to modelling reaction-diffusion systems with anomalous transport rely on deterministic equations, and ignore fluctuations arising due to finite particle numbers. Starting from an individual-based model we use a generating-functional approach ... More

A 3D radiative transfer framework: III. periodic boundary conditionsAug 05 2008We present a general method to solve radiative transfer problems including scattering in the continuum as well as in lines in 3D configurations with periodic boundary conditions. he scattering problem for line transfer is solved via means of an operator ... More

Improved discretization of the wavelength derivative term in CMF operator splitting numerical radiative transferJan 09 2004We describe two separate wavelength discretization schemes that can be used in the numerical solution of the comoving frame radiative transfer equation. We present an improved second order discretization scheme and show that it leads to significantly ... More

Bolometric Lightcurves of Peculiar Type II-P SupernovaeAug 30 2016We examine the bolometric lightcurves of five Type II-P supernovae (SNe 1998A, 2000cb, 2006V, 2006au and 2009E) which are thought to originate from blue supergiant progenitors using a new python package named SuperBoL. With this code, we calculate SNe ... More

Experimental observation of dispersion of non-hydrodynamic collective optic excitations in molten NaIJan 10 2018High-resolution inelastic x-ray scattering measurements were carried out on molten NaI near the melting point at 680$^\circ$C at SPring-8. Small and damped indications of longitudinal optic excitation modes were observed on the tails of the longitudinal ... More

Partially quenched study of strange baryon with Nf = 2 twisted mass fermionsMay 18 2009Jun 24 2009We present results on the mass of the baryon octet and decuplet using two flavors of light dynamical twisted mass fermions. The strange quark mass is fixed to its physical value from the kaon sector in a partially quenched set up. Calculations are performed ... More

A 3D radiative transfer framework: IV. spherical & cylindrical coordinate systemsMar 11 2009We extend our framework for 3D radiative transfer calculations with a non-local operator splitting methods along (full) characteristics to spherical and cylindrical coordinate systems. These coordinate systems are better suited to a number of physical ... More

Comparative Direct Analysis of Type Ia Supernova Spectra. IV. PostmaximumDec 14 2007A comparative study of optical spectra of Type Ia supernovae (SNe Ia) obtained near 1 week, 3 weeks, and 3 months after maximum light is presented. Most members of the four groups that were defined on the basis of maximum light spectra in Paper II (core ... More

On the Cycle Space of a Random GraphOct 05 2016Write $\mathcal{C}(G)$ for the cycle space of a graph $G$, $\mathcal{C}_\kappa(G)$ for the subspace of $\mathcal{C}(G)$ spanned by the copies of the $\kappa$-cycle $C_\kappa$ in $G$, $\mathcal{T}_\kappa$ for the class of graphs satisfying $\mathcal{C}_\kappa(G)=\mathcal{C}(G)$, ... More

Quantum corrections to dynamical holographic thermalization: entanglement entropy and other non-local observablesMay 10 2013Aug 06 2013We investigate the thermalization time scale in the planar limit of the SU(N) N=4 SYM plasma at strong yet finite 't Hooft coupling by considering its supergravity dual description, including the full O(alpha'^3) type IIB string theory corrections. We ... More

The New Standard Stellar Population Models (NSSPM) -- The PrologueJan 23 2007We are developing a brand new stellar population models with flexible chemistry (isochrones plus stellar colors and spectra) in order to set a new standard of completeness and excellence. Here we present preliminary results to assess the effects of stellar ... More

Direct Analysis of Spectra of the Peculiar Type Ia Supernova 2000cxJan 15 2004The Type Ia SN 2000cx exhibited multiple peculiarities, including a lopsided B-band light-curve peak that does not conform to current methods for using shapes of light curves to standardize SN Ia luminosities. We use the parameterized supernova synthetic-spectrum ... More

A First Transients Survey with JWST: the FLARE projectOct 19 2017Nov 26 2017JWST was conceived and built to answer one of the most fundamental questions that humans can address empirically: "How did the Universe make its first stars?". Our First Lights At REionization (FLARE) project transforms the quest for the epoch of reionization ... More

Detailed Spectroscopic Analysis of SN 1987A: The Distance to the LMC using the SEAM methodMar 31 2002Supernova 1987A remains the most well-studied supernova to date. Observations produced excellent broad-band photometric and spectroscopic coverage over a wide wavelength range at all epochs. We model the observed spectra from Day 1 to Day 81 using a hydrodynamical ... More

Bond stretching phonon softening and angle-resolved photoemission kinks in optimally doped Bi2Sr1.6La0.4Cu2O6 superconductorsApr 08 2008We report the first measurement of the optical phonon dispersion in optimally doped single layer Bi2Sr1.6La0.4Cu2O6+delta using inelastic x-ray scattering. We found a strong softening of the Cu-O bond stretching phonon at about q=(0.25,0,0) from 76 to ... More