Results for "K. E. Smith"

total 169957took 0.15s
Exclusive electroproduction of phi mesons at 4.2 GeVJan 18 2001Apr 10 2001We studied the exclusive reaction e p --> e' p' phi using the phi --> K^+ K^- decay mode. The data were collected using a 4.2 GeV incident electron beam and the CLAS detector at Jefferson Lab. Our experiment covers the range in Q^2 from 0.7 to 2.2 GeV^2, ... More
Implementing the LPM effect in a parton cascade modelJan 25 2011Parton Cascade Models (PCM), which describe the full time-evolution of a system of quarks and gluons using pQCD interactions are ideally suited for the description of jet production, including the emission, evolution and energy-loss of the full parton ... More
`Eppur Si Muove': On The Motion of the Acoustic Peak in the Correlation FunctionMar 26 2007Dec 02 2007The baryonic acoustic signature in the large-scale clustering pattern of galaxies has been detected in the two-point correlation function. Its precise spatial scale has been forwarded as a rigid-rod ruler test for the space-time geometry, and hence as ... More
Light Element Abundance Patterns in the Orion Association: I) HST Observations of Boron in G-dwarfsMay 22 2000The boron abundances for two young solar-type members of the Orion association, BD -6 1250 and HD 294297, are derived from HST STIS spectra of the B I transition at 2496.771 A. The best-fit boron abundances for the target stars are 0.13 and 0.44 dex lower ... More
The impact of halo shapes on the bispectrum in cosmologyAug 17 2005Oct 05 2005(Abridged) We use the triaxial halo model of Smith & Watts to investigate the impact of dark matter halo shapes on the bispectrum. Analytic expressions are derived and evaluated through numerical integration. Two models for the ellipsoidal halo profiles ... More
New HI Features of the Magellanic SystemNov 09 1998The first results from the HI Parkes All-Sky Survey (HIPASS) provide a spectacular view of the global HI distribution in the vicinity of the Magellanic Clouds and the southern Milky Way. A 2400 square degree mosaic around the South Celestial Pole (SCP) ... More
An analytic model for the bispectrum of galaxies in redshift spaceDec 03 2007Mar 18 2008We develop an analytic theory for the redshift space bispectrum of dark matter, haloes and galaxies. This is done within the context of the halo model of structure formation, as this allows for the self-consistent inclusion of linear and non-linear redshift ... More
The Scale Dependence of Halo and Galaxy Bias: Effects in Real SpaceSep 20 2006Mar 27 2007We examine the scale dependence of dark matter, halo and galaxy clustering on very large scales (0.01<k[h/Mpc]<0.15), due to non-linear effects from dynamics and halo bias. We pursue a two line offensive: high resolution numerical simulations are used ... More
An Empirical Bayes Approach to Regularization Using Previously Published ModelsOct 11 2017This manuscript proposes a novel empirical Bayes technique for regularizing regression coefficients in predictive models. When predictions from a previously published model are available, this empirical Bayes method provides a natural mathematical framework ... More
Cloud Structure and Physical Conditions in Star-forming Regions from Optical Observations. I. Data and Component StructureDec 03 2003We present high-resolution optical spectra (at ~0.6--1.8 km s-1) of interstellar CN, CH, CH^+, \ion{Ca}{1}, \ion{K}{1}, and \ion{Ca}{2} absorption toward 29 lines of sight in three star-forming regions, \rho Oph, Cep OB2, and Cep OB3. The observations ... More
Fluorine in the Solar neighborhood: No evidence for the neutrino processDec 13 2016Dec 16 2016Asymptotic Giant Branch stars are known to produce `cosmic' fluorine but it is uncertain whether these stars are the main producers of fluorine in the Solar neighborhood or if any of the other proposed formation sites, type II supernovae and/or Wolf-Rayet ... More
Integral field spectroscopy of H2 and CO emission in IRAS 18276-1431: evidence for ongoing post-AGB mass lossSep 28 2010We present K-band integral field spectroscopy of the bipolar post-AGB object IRAS 18276-1431 (OH 17.7-2.0) using SINFONI on the VLT. This allows us to image both the continuum and molecular features in this object from 1.95-2.45{\mu}m with a spatial resolution ... More
Switchable collective pinning of flux quanta using magnetic vortex arraysMar 31 2008We constructed a superconducting/ferromagnetic hybrid system in which the ordering of the pinning potential landscape for flux quanta can be manipulated. Flux pinning is induced by an array of magnetic nanodots in the magnetic vortex state, and controlled ... More
The Magellanic Stream, High-Velocity Clouds and the Sculptor GroupSep 06 2002The Magellanic Stream is a 100\deg x 10\deg filament of gas which lies within the Galactic halo and contains ~ 2 x 10^8 \Msun of neutral hydrogen. We present data from the HI Parkes All Sky Survey (HIPASS) in the first complete survey of the entire Magellanic ... More
The Pattern Basis Approach to Circuit ComplexityJun 16 2016We describe and motivate a proposed new approach to lowerbounding the circuit complexity of boolean functions, based on a new formalization of "patterns" as elements of a special basis of the vector space of all truth table properties. We prove that a ... More
The Case for Durative Actions: A Commentary on PDDL2.1Sep 26 2011The addition of durative actions to PDDL2.1 sparked some controversy. Fox and Long argued that actions should be considered as instantaneous, but can start and stop processes. Ultimately, a limited notion of durative actions was incorporated into the ... More
On the Unique Ergodicity of Quadratic Differentials and the Orientation Double CoverApr 20 2017Nov 04 2018We construct an example of a uniquely ergodic measured foliation on a surface such that the associated translation flow on the orientation double cover is minimal but not uniquely ergodic. We then prove a geometric criterion for the horizontal foliation ... More
An Introduction to Tight ClosureSep 26 2002This is an expanded version of the author's lecture at the Conference in Commutative Algebra and Algebraic Geometry in Messina Italy in June 1999. The purpose of the talk was to give a brief introduction to the subject of tight closure, aimed at commutative ... More
Infrared Surveys for AGNMar 06 2002From the earliest extragalactic infrared studies AGN have shown themselves to be strong infrared sources and IR surveys have revealed new populations of AGN. I briefly review current motivations for AGN surveys in the infrared and results from previous ... More
Expressions for frictional and conservative force combinations within the dissipative Lagrange-Hamilton formalismJan 18 2006Dissipative Lagrangians and Hamiltonians having Coulomb, viscous and quadratic damping,together with gravitational and elastic terms are presented for a formalism that preserves the Hamiltonian as a constant of the motion. Their derivations are also shown. ... More
Local Cohomology and Base ChangeJun 30 2016Let $X \overset{f}\longrightarrow S$ be a morphism of Noetherian schemes, with $S$ reduced. For any closed subscheme $Z$ of $X$ finite over $S$, let $j$ denote the open immersion $X\setminus Z \hookrightarrow X$. Koll\'ar asked whether for any coherent ... More
Tight closure commutes with localization in binomial ringsSep 13 2002Jan 20 2003It is proved that tight closure commutes with localization in any domain which has a module finite extension in which tight closure is known to commute with localization. It follows that tight closure commutes with localization in binomial rings, in particular ... More
Improved Experimental Limits on the Production of Magnetic MonopolesMay 03 2000We present new limits on low mass accelerator-produced point-like Dirac magnetic monopoles trapped and bound in matter surrounding the D\O collision region of the Tevatron at Fermilab (experiment E-882). In the context of a Drell-Yan mechanism, we obtain ... More
Maximum entropy deconvolution of resonant inelastic x-ray scattering spectraJul 20 2011Feb 10 2012Resonant inelastic x-ray scattering (RIXS) has become a powerful tool in the study of the electronic structure of condensed matter. Although the linewidths of many RIXS features are narrow, the experimental broadening can often hamper the identification ... More
Towards Rapid Parameter Estimation on Gravitational Waves from Compact Binaries using Interpolated WaveformsNov 06 2012Accurate parameter estimation of gravitational waves from coalescing compact binary sources is a key requirement for gravitational-wave astronomy. Evaluating the posterior probability density function of the binary's parameters (component masses, sky ... More
New Limits on the Production of Magnetic Monopoles at FermilabSep 01 2000First results from an experiment (Fermilab E882) searching for magnetically charged particles bound to elements from the CDF and D{\O}detectors are reported. The experiment is described, and limits on magnetic monopole pair production cross sections for ... More
Sub-Wavelength Multi-Channel Imaging Using a Solid Immersion Lens: Spectroscopy of Excitons in Single Quantum DotsAug 25 2004We demonstrate sub-wavelength imaging of excitons confined to single CdTe quantum dots. By combining slit-confocal microscopy with a hemispherical solid immersion lens we simultaneously map the emission of thousands of single quantum dots with a spatial ... More
ALMA, ATCA, and Spitzer Observations of the Luminous Extragalactic Supernova SN 1978KNov 27 2018Only three extragalactic supernovae have been detected at late times at millimeter wavelengths: SN 1987A, SN 1978K, and SN 1996cr. SN 1978K is a remarkably luminous Type IIn supernova that remains bright at all wavelengths 40 years after its explosion. ... More
Magnetically modulated accretion in T Tauri starsFeb 11 1995We examine how accretion on to T Tauri stars may be modulated by a time-dependent `magnetic gate' where the inner edge of the accretion disc is disrupted by a varying stellar field. We show that magnetic field variations on time-scales shorter than 10^5 ... More
Black hole head-on collisions and gravitational waves with fixed mesh-refinement and dynamic singularity excisionMar 16 2005Jun 20 2005We present long-term-stable and convergent evolutions of head-on black hole collisions and extraction of gravitational waves generated during the merger and subsequent ring-down. The new ingredients in this work are the use of fixed mesh-refinement and ... More
Moving black holes via singularity excisionJan 27 2003We present a singularity excision algorithm appropriate for numerical simulations of black holes moving throughout the computational domain. The method is an extension of the excision procedure previously used to obtain stable simulations of single, non-moving ... More
Detection of the Missing Baryons toward the Sightline of H1821+643Dec 11 2018Based on constraints from Big Bang nucleosynthesis and the cosmic microwave background, the baryon content of the high-redshift Universe can be precisely determined. However, at low redshift, about one-third of the baryons remain unaccounted for, which ... More
Charm Quark Energy Loss In Infinite QCD Matter Using A Parton Cascade ModelSep 05 2013Jan 27 2015We utilize the Parton Cascade Model to study the evolution of charm quarks propagating through a thermal brick of QCD matter. We determine the energy loss and the transport coefficient '$\hat{q}$' for charm quarks. The calculations are done at a constant ... More
The Gaseous Trail of the Sagittarius Dwarf GalaxyJan 22 2004A possible gaseous component to the stream of debris from the Sagittarius dwarf galaxy is presented. We identify 4 - 10 x 10^6 Msun of neutral hydrogen along the orbit of the Sgr dwarf in the direction of the Galactic anticenter (at 36 kpc, the distance ... More
The Component Star Masses in RW TriDec 09 2002We use time-resolved spectra of the cataclysmic variable RW Tri in the I and K-band to determine the orbital velocity of the secondary star using skew mapping and cross correlation techniques respectively. We find radial velocity amplitudes of 250+/-47km/s ... More
Observing the dynamics of super-massive black hole binaries with Pulsar Timing ArraysJul 24 2012Pulsar Timing Arrays are a prime tool to study unexplored astrophysical regimes with gravitational waves. Here we show that the detection of gravitational radiation from individually resolvable super-massive black hole binary systems can yield direct ... More
A catalogue of faint local radio AGN and the properties of their host galaxiesMay 21 2018We present a catalogue of local ($z<0.1$) galaxies that contain faint AGN. We select these objects by identifying galaxies that exhibit a significant excess in their radio luminosities, compared to what is expected from the observed levels of star-formation ... More
The Galaxy's Eating HabitsNov 03 2003The possibility of a gaseous halo stream which was stripped from the Sagittarius dwarf galaxy is presented. The total mass of the neutral hydrogen along the orbit of the Sgr dwarf in the direction of the Galactic anticenter is 4-10 x 10^6 Msun (at 36 ... More
FCC 35 and its HI Companion: Multi-Wavelength Observations and InterpretationMar 25 1998The Fornax cluster galaxy FCC 35 shows an unusual multiply-peaked integrated HI profile (Bureau, Mould & Staveley-Smith 1996). We have now observed FCC 35 with the Australia Telescope Compact Array (ATCA) and have found a compact HI source with M_{HI} ... More
The Heavy-Flavour Contribution to Proton StructureSep 25 1996We present theoretical and experimental considerations pertaining to deeply inelastic heavy-flavour production at HERA. The various theoretical uncertainties in the cross section calculation are discussed. Cuts are imposed to determine the fraction of ... More
Limits on Production of Magnetic Monopoles Utilizing Samples from the DO and CDF Detectors at the TevatronJun 20 2003We present 90% confidence level limits on magnetic monopole production at the Fermilab Tevatron from three sets of samples obtained from the D0 and CDF detectors each exposed to a proton-antiproton luminosity of $\sim175 {pb}^{-1}$ (experiment E-882). ... More
Optical Orientation of Excitons in CdSe Self-Assembled Quantum DotsNov 01 2004We study spin dynamics of excitons confined in self-assembled CdSe quantum dots by means of optical orientation in magnetic field. At zero field the exciton emission from QDs populated via LO phonon-assisted absorption shows a circular polarization of ... More
Detection of the Neupert Effect in the Corona of an RS CVn Binary System by XMM-Newton and the VLAJun 05 2002The RS CVn-type binary $\sigma$ Geminorum was observed during a large, long-duration flare simultaneously with {\it XMM-Newton} and the VLA. The light curves show a characteristic time dependence that is compatible with the Neupert effect observed in ... More
The distribution of local star formation activity as a function of galaxy stellar mass, environment and morphologySep 05 2017We present a detailed inventory of star formation in the local Universe, dissecting the cosmic star formation budget as a function of key variables that influence the star formation rate (SFR) of galaxies: stellar mass, local environment and morphology. ... More
A New, Low Braking Index For the LMC Pulsar B0540-69Aug 05 2016We report the results of a 16-month monitoring campaign using the Swift satellite of PSR B0540-69, a young pulsar in the Large Magellanic Cloud. Phase connection was maintained throughout the campaign so that a reliable ephemeris could be determined, ... More
Discovery of a Spin-Down State Change in the LMC Pulsar B0540-69Jun 18 2015We report the discovery of a large, sudden, and persistent increase in the spin-down rate of B0540-69, a young pulsar in the Large Magellanic Cloud, using observations from the Swift and RXTE satellites. The relative increase in the spin-down rate of ... More
Upper critical field study in the organic superconductor $β''$-(ET)$_{2}$SF$_{5}$CH$_{2}$CF$_{2}$SO$_{3}$ : Possibility of Fulde-Ferrell-Larkin-Ovchinnikov stateNov 24 2008Jun 18 2009We report upper critical field measurements in the metal-free-all-organic superconductor $\beta''$-(ET)$_{2}$SF$_{5}$CH$_{2}$CF$_{2}$SO$_{3}$ obtained from measuring the in-plane penetration depth using the tunnel diode oscillator technique. For magnetic ... More
The Giant Flare of December 27, 2004 from SGR 1806-20Nov 09 2006The giant flare of December 27, 2004 from SGR 1806-20 represents one of the most extraordinary events captured in over three decades of monitoring the gamma-ray sky. One measure of the intensity of the main peak is its effect on X- and gamma-ray instruments. ... More
A supernova distance to the anchor galaxy NGC 4258Sep 01 2015Sep 04 2015The fortuitous occurrence of a type II-Plateau (IIP) supernova, SN 2014bc, in a galaxy for which distance estimates from a number of primary distance indicators are available provides a means with which to cross-calibrate the standardised candle method ... More
Mid-infrared spectroscopy of the Andromeda galaxySep 18 2015We present Spitzer/Infrared Spectrograph (IRS) 5-21 micron spectroscopic maps towards 12 regions in the Andromeda galaxy (M31). These regions include the nucleus, bulge, an active region in the star-forming ring, and 9 other regions chosen to cover a ... More
A surface-aware projection basis for quasigeostrophic flowJun 20 2012Recent studies indicate that altimetric observations of the ocean's mesoscale eddy field reflect the combined influence of surface buoyancy and interior potential vorticity anomalies. The former have a surface-trapped structure, while the latter have ... More
Finer-grained Locking in Concurrent Dynamic Planar Convex HullsFeb 09 2017The convex hull of a planar point set is the smallest convex polygon containing each point in the set. The dynamic convex hull problem concerns efficiently maintaining the convex hull of a set of points subject to additions and removals. One algorithm ... More
The Structure of Galaxies: I. Surface Photometry TechniquesMar 12 2012This project uses the 2MASS all-sky image database to study the structure of galaxies over a range of luminosities, sizes and morphological types. This first paper in this series will outline the techniques, reliability and data products to our surface ... More
Soft X-ray Scattering and Halos from DustOct 21 1997Small angle scatterings of X-rays by interstellar dust particles create halos around x-ray sources. By observing these halos with sufficient angular resolution it is possible to derive information about both the spatial distribution of the dust along ... More
Aesthetics and Astronomy: Studying the public's perception and understanding of non-traditional imagery from spaceSep 03 2010Some 400 years after Galileo, modern telescopes have enabled humanity to "see" what the natural eye cannot. Astronomical images today contain information about incredibly large objects located across vast distances and reveal information found in "invisible" ... More
What is the optimal way to measure the galaxy power spectrum?Jul 15 2015Measurements of the galaxy power spectrum contain a wealth of information about the Universe. Its optimal extraction is vital if we are to truly understand the micro-physical nature of dark matter and dark energy. In Smith & Marian (2015) we generalized ... More
Strong late-time circumstellar interaction in the peculiar supernova iPTF14hlsDec 01 2017Jan 11 2018We present a moderate-resolution spectrum of the peculiar Type II supernova iPTF14hls taken on day 1153 after discovery. This spectrum reveals the clear signature of shock interaction with dense circumstellar material (CSM). We suggest that this CSM interaction ... More
Examining Perceptions of Astronomy Images Across Mobile PlatformsMar 23 2014Modern society has led many people to become consumers of data unlike previous generations. How this shift in the way information is communicated and received - including in areas of science - and affects perception and comprehension is still an open ... More
Statistical properties of the linear tidal shearMay 14 2008Aug 14 2008Large-scale structures originate from coherent motions induced by inhomogeneities in the primeval gravitational potential. Here, we investigate the two-point statistics of the second derivative of the potential, the tidal shear, under the assumption of ... More
Towards optimal estimation of the galaxy power spectrumMar 23 2015Aug 28 2015The galaxy power spectrum encodes a wealth of information about cosmology and the matter fluctuations. Its unbiased and optimal estimation is therefore of great importance. In this paper we generalise the framework of Feldman et al. (1994) to take into ... More
Toward optimal cluster power spectrum analysisJun 06 2014Aug 28 2015The power spectrum of galaxy clusters is an important probe of the cosmological model. In this paper we determine the optimal weighting scheme for maximizing the signal-to-noise ratio for such measurements. We find a closed form analytic expression for ... More
Cosmological perturbation theory for baryons and dark matter I: one-loop corrections in the RPT frameworkOct 28 2009Dec 18 2009We generalize the `renormalized' perturbation theory (RPT) formalism of Crocce & Scoccimarro (2006a) to deal with multiple fluids in the Universe and here we present calculations up to the one-loop level. We apply the approach to the non-linear evolution ... More
Core versus graded core and global sections of line bundlesJan 17 2003Apr 21 2003We find formulas for the graded core of certain m-primary ideals in a graded ring. In particular, if S is the section ring of an ample line bundle on a Cohen-Macaulay complex projective variety, we show that under suitable hypothesis, the core and graded ... More
On a Non-Vanishing Conjecture of Kawamata and the Core of an IdealJan 17 2003We show that under suitable hypothesis (which are sharp in certain sense) that the core of an m-primary ideal in a regular local ring of dimension d is equal to the adjoint (or multiplier) ideal of its d-th power, generalizing a result of Huneke and Swanson ... More
Linear bounds on growth of associated primesSep 23 2002We find explicit bounds on the primary components and on the Castelnuovo-Mumford regularity of powers of monomial ideals. We also analyze the primary decompositions of Katzman's example.
Valuations and FrobeniusJul 21 2015Dec 29 2016The behavior of the Frobenius map is investigated for valuation rings of prime characteristic. We show that valuation rings are always F-pure. We introduce a generalization of the notion of strong F-regularity, which we call F-pure regularity, and show ... More
VLT / Infrared Integral Field Spectrometer Observations of Molecular Hydrogen Lines in the Knots in the Planetary Nebula NGC 7293 (the Helix Nebula)Sep 19 2007Knots are commonly found in nearby planetary nebulae (PNe) and star forming regions. Within PNe, knots are often found to be associated with the brightest parts of the nebulae and understanding the physics involved in knots may reveal the processes dominating ... More
Valuations and FrobeniusJul 21 2015Jul 30 2015The behavior of the Frobenius map is investigated for valuation rings of prime characteristic. We show that valuation rings are always F-pure. We introduce a generalization of the notion of strong F-regularity, which we call F-pure regularity, and show ... More
Frobenius Splitting in Commutative AlgebraSep 03 2014This is a survey of Frobenius splitting techniques in commutative algebra, based on the first author's lectures at the introductory workshop for the special year in commutative algebra at MSRI in fall 2012.
Cosmology with Phase Statistics: Parameter Forecasts and Detectability of BAONov 03 2016We consider an alternative to conventional three-point statistics such as the bispectrum, which is purely based on the Fourier phases of the density field: the line correlation function. This statistic directly probes the non-linear clustering regime ... More
Rational and Non-Rational Algebraic Varieties: Lectures of János KollárJul 15 1997This is a detailed write-up of Koll\'ar's course at the EMS summer school in Algebraic Geometry in Eger, Hungary, August 1996. The topics include definitions and examples of rational and unirational varieties, with special attention to varieties defined ... More
Excellence in prime characteristicApr 12 2017Jan 18 2018Fix any field $K$ of characteristic $p$ such that $[K:K^p]$ is finite. We discuss excellence for Noetherian domains whose fraction field is $K$, showing for example, that $R$ is excellent if and only if the Frobenius map is finite on $R$. Furthermore, ... More
Fast Mixing of Metropolis-Hastings with Unimodal TargetsJun 19 2018A well-known folklore result in the MCMC community is that the Metropolis-Hastings algorithm mixes quickly for any unimodal target, as long as the tails are not too heavy. Although we've heard this fact stated many times in conversation, we are not aware ... More
Black Holes and Vacuum Cleaners: Using Metaphor, Relevance, and Inquiry in Labels for Space ImagesMar 06 2017This study extended research on the development of explanatory labels for astronomical images for the non-expert lay public. The research questions addressed how labels with leading questions/metaphors and relevance to everyday life affect comprehension ... More
The asymmetric radio remnant of SN 1987ADec 27 1996We present seven years of radio observations of SN 1987A made with the Australia Telescope Compact Array. At 1.4, 2.4, 4.8 and 8.6 GHz, the flux density of the radio remnant has increased monotonically since emission was redetected 1200 days after the ... More
The Evolution of Copper in the Globular Cluster Omega CentauriMar 22 2002Mar 25 2002Copper abundances are presented for 40 red-giant stars in Omega Cen as well as 15 red-giant members of the globular clusters NGC288, NGC362, NGC3201, NGC6752, and M4. A comparison with the halo field star pattern indicates that, unlike the field stars, ... More
Chandra Observations of MBM12 and Models of the Local BubbleJan 04 2005Chandra observations toward the nearby molecular cloud MBM12 show unexpectedly strong and nearly equal foreground O VIII and O VII emission. As the observed portion of MBM12 is optically thick at these energies, the emission lines must be formed nearby, ... More
Charge-Density-Wave induced modifications to the quasiparticle self-energy in 2H TaSe2May 26 2000Nov 01 2000The self-energy of the photo-hole in 2H-TaSe2 is measured by angle-resolved photoemission spectroscopy (ARPES) as a function of binding energy and temperature. In the charge-density wave (CDW) state, a structure in the self- energy is detected at ~ 65 ... More
Magneto-photoluminescence measurements of symmetric and asymmetric CdSe/ZnSe self-assembled quantum dotsAug 29 2003We study the excitonic structure of CdSe/ZnSe self assembled quantum dots (SAQD) by magneto-photoluminescence (PL) spectroscopy. Using fixed 200 nm apertures through a metal film, we are able to probe single narrow (200 micro-eV) spectroscopic lines emitted ... More
Studies of orbital parameters and pulse profile of the accreting millisecond pulsar XTE J1807-294Jul 01 2004The accreting millisecond pulsar XTE J1807-294 was observed by XMM-Newton on March 22, 2003 after its discovery on February 21, 2003 by RXTE. The source was detected in its bright phase with an observed average count rate of 33.3 cts/s in the EPIC-pn ... More
Nano-engineering of electron correlation in oxide superlatticesMar 14 2019Oxide heterostructures and superlattices have attracted a great deal of attention in recent years owing to the rich exotic properties encountered at their interfaces. We focus on the potential of tunable correlated oxides by investigating the spectral ... More
Enhanced electron correlations at the SrxCa1-xVO3 surfaceApr 20 2015We report hard x-ray photoemission spectroscopy measurements of the electronic structure of the prototypical correlated oxide SrxCa1-xVO3. By comparing spectra recorded at different excitation energies, we show that 2.2 keV photoelectrons contain a substantial ... More
Warm Molecular Gas in M51: Mapping the Excitation Temperature and Mass of H_2 with the Spitzer Infrared SpectrographNov 30 2007We have mapped the warm molecular gas traced by the H_2 S(0) - H_2 S(5) pure rotational mid-infrared emission lines over a radial strip across the nucleus and disk of M51 (NGC 5194) using the Infrared Spectrograph (IRS) on the Spitzer Space Telescope. ... More
The trapping and escape of buoyant vortex rings in sharply stratified fluidsOct 15 2011In this fluid dynamics video we study the dynamics of miscible vortex rings falling in ambient strongly (near two-layer) stratified fluid. Experiments and direct numerical simulations using the variable density Navier-Stokes (VARDEN) solver are presented ... More
Color Classification of Extrasolar Giant Planets: Prospects and CautionsJul 23 2018Atmospheric characterization of directly imaged planets has thus far been limited to ground-based observations of young, self-luminous, Jovian planets. Near-term space- and ground- based facilities like \emph{WFIRST} and ELTs will be able to directly ... More
Dependence of X-Ray Burst Models on Nuclear Reaction RatesJul 09 2016X-ray bursts are thermonuclear flashes on the surface of accreting neutron stars and reliable burst models are needed to interpret observations in terms of properties of the neutron star and the binary system. We investigate the dependence of X-ray burst ... More
Analysis of trap spectra in LEC and epitaxial GaAsNov 30 1999Different methods of trap parameter measurement are analysed. Transient photoconductivity and thermally stimulated effects were used to investigate the influence of traps in LEC SI-GaAs and high resistivity epitaxial GaAs. The peculiarities of the TSC ... More
Bispectrum speckle interferometry of the massive protostellar outflow source IRAS 23151+5912Nov 07 2005We present bispectrum speckle interferometry of the massive protostellar object IRAS 23151+5912 in the near-infrared K' band. The reconstructed image shows the diffuse nebulosity north-east of two point-like sources in unprecedented detail. The comparison ... More
Monitoring RXTE Observations of Markarian 348: the origin of the column density variationsDec 12 2001We analyze 37 RXTE observations of the type 2 Seyfert galaxy Mrk348 obtained during a period of 14 months. We confirm the spectral variability previous reported by Smith et al., in the sense that thecolumn density decreases by a factor of ~3 as the count ... More
Uniform Contribution of Supernova Explosions to the Chemical Enrichment of Abell 3112 out to R200Sep 12 2016The spatial distribution of the metals residing in the intra-cluster medium (ICM) of galaxy clusters records all the information on a cluster's nucleosynthesis and chemical enrichment history. We present measurements from deep Suzaku and Chandra observations ... More
Supernova 1987A: A young supernova remnant in an aspherical progenitor windSep 23 1999The interaction between the ejecta from Supernova 1987A and surrounding material is producing steadily brightening radio and X-ray emission. The new-born supernova remnant has been significantly decelerated by this interaction, while its morphology reflects ... More
LoCuSS: Luminous infrared galaxies in the merging cluster Abell 1758 at z=0.28Mar 27 2009We present the first galaxy evolution results from the Local Cluster Substructure Survey (LoCuSS), a multi-wavelength survey of 100 X-ray selected galaxy clusters at 0.15<z<0.30. LoCuSS combines far-UV through far-IR observations of cluster galaxies with ... More
Uniform Contribution of Supernova Explosions to the Chemical Enrichment of Abell 3112 out to R200Sep 12 2016Jan 03 2017The spatial distribution of the metals residing in the intra-cluster medium (ICM) of galaxy clusters records all the information on a cluster's nucleosynthesis and chemical enrichment history. We present measurements from a total of 1.2 Ms Suzaku XIS ... More
Spectral Analysis of GRBs Measured by RHESSIApr 23 2007The Ge spectrometer of the RHESSI satellite is sensitive to Gamma Ray Bursts (GRBs) from about 40 keV up to 17 MeV, thus ideally complementing the Swift/BAT instrument whose sensitivity decreases above 150 keV. We present preliminary results of spectral ... More
The average X-ray/gamma-ray spectrum of radio-quiet Seyfert 1sJul 03 1996We have obtained the average 1--500 keV spectrum of radio-quiet Seyfert 1s using data from EXOSAT, Ginga, HEAO, and GRO/OSSE. The spectral fit to the combined average EXOSAT and OSSE data is fully consistent with that for Ginga and OSSE, confirming results ... More
Octahedral rotation patterns in strained EuFeO3 and other Pbnm perovskite films: Implications for hybrid improper ferroelectricityJun 10 2016We report the relationship between epitaxial strain and the crystallographic orientation of the in-phase rotation axis and A-site displacements in Pbnm-type perovskite films. Synchrotron diffraction measurements of EuFeO3 films under strain states ranging ... More
Spatially-Resolved Spectroscopy of SDSS J0952+2552: a Confirmed Dual AGNJul 13 2011Sep 20 2011Most massive galaxies contain supermassive black holes (SMBHs) in their cores. When galaxies merge, gas is driven to nuclear regions and can accrete onto the central black hole. Thus one expects to see dual AGN in a fraction of galaxy mergers. Candidates ... More
Adaptive Optics Imaging of QSOs with Double-Peaked Narrow Lines: Are they Dual AGNs?Feb 08 2011Jul 07 2011Active galaxies hosting two accreting and merging super-massive black holes (SMBHs) -- dual Active Galactic Nuclei (AGN) -- are predicted by many current and popular models of black hole-galaxy co-evolution. We present here the results of a program that ... More
LAMOST DR1: Stellar parameters and chemical abundances with SP_AceMar 06 2018We present a new analysis of the LAMOST DR1 survey spectral database performed with the code SP_Ace, which provides the derived stellar parameters T$_{\rm eff}$, log (g), [Fe/H], and [$\alpha$/Fe] for 1,097,231 stellar objects. We tested the reliability ... More
Globally $F$-regular and log Fano varietiesMay 04 2009Dec 23 2009We prove that every globally $F$-regular variety is log Fano. In other words, if a prime characteristic variety $X$ is globally $F$-regular, then it admits an effective $\bQ$-divisor $\Delta$ such that $-K_X - \Delta$ is ample and $(X, \Delta)$ has controlled ... More