Results for "Nicholas P. Ross"

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Search for primordial non-Gaussianity in the quasars of SDSS-III BOSS DR9Oct 24 2013Apr 01 2014We analyse the clustering of 22,361 quasars between redshift 2.2 < z < 2.9 observed with the Sloan Digital Sky Survey (SDSS)-III Baryon Oscillation Spectroscopic Survey (BOSS), which are included in the ninth data release (DR9). We fit the clustering ... More
On the Oscillation of SpeciesDec 12 2013Aug 10 2014We describe a new class of BPS objects called magnetubes: their supersymmetry is determined by their magnetic charges, while their electric charges can oscillate freely between different species. We show how to incorporate these objects into microstate ... More
The Evolution of Post-Starburst Galaxies from $z\sim1$ to the PresentOct 27 2014Aug 15 2016Post-starburst galaxies are in the transitional stage between blue, star-forming galaxies and red, quiescent galaxies, and therefore hold important clues for our understanding of galaxy evolution. In this paper, we systematically searched for and identified ... More
Coiffured Black RingsMay 20 2014We describe a new type of hair on supersymmetric black string and black ring solutions, which produces the largest known violation of black hole uniqueness, parameterized by an arbitrary function and hence an infinite number of continuous parameters. ... More
Opportunities in Time-Domain Extragalactic Astrophysics with the NASA Near-Earth Object Camera (NEOCam)Apr 12 2019This White Pape motivates the time domain extragalactic science case for the NASA Near-Earth Object Camera (NEOCam). NEOCam is a NASA Planetary mission whose goal is to discover and characterize asteroids and comets, to assess the hazard to Earth from ... More
Radio galaxies in the 2SLAQ Luminous Red Galaxy survey: II. The stellar populations of radio-loud and radio-quiet LRGsNov 21 2007We present an analysis of the optical spectra of a volume-limited sample of 375 radio galaxies at redshift 0.4<z<0.7 from the 2dF-SDSS Luminous Red Galaxy and QSO (2SLAQ) redshift survey. We investigate the evolution of the stellar populations and emission-line ... More
A cell filtration of the restriction of a cell moduleApr 08 2015We give a new proof that the restriction of a cell module of the Hecke algebra of the symmetric group on $n$ letters, to the Hecke algebra of the symmetric group on $n-1$ letters, has a filtration by cell modules.
Luminosity Upgrades for ILCAug 16 2013The possibility of increasing the luminosity for the ILC at Ecm < 350 GeV centre-of-mass by increasing the beam power are considered. It will be shown that an approximately constant luminosity can be achieved across the centre of mass energy range (250-500 ... More
Cone Schedules for Processing Systems in Fluctuating EnvironmentsMay 02 2011We consider a generalized processing system having several queues, where the available service rate combinations are fluctuating over time due to reliability and availability variations. The objective is to allocate the available resources, and corresponding ... More
Intrinsic galaxy alignments from the 2SLAQ and SDSS surveys: luminosity and redshift scalings and implications for weak lensing surveysJan 24 2007Oct 28 2007Correlations between intrinsic shear and the density field on large scales, a potentially important contaminant for cosmic shear surveys, have been robustly detected at low redshifts with bright galaxies in SDSS data. Here we present a more detailed characterization ... More
Clustering of intermediate redshift quasars using the final SDSS III-BOSS sampleJul 30 2015We measure the two-point clustering of spectroscopically confirmed quasars from the final sample of the Baryon Oscillation Spectroscopic Survey (BOSS) on comoving scales of 4 < s < 22 Mpc/h. The sample covers 6950 deg^2 (~ 19 (Gpc/h)^3) and, over the ... More
Mean Spectral Energy Distributions and Bolometric Corrections for Luminous QuasarsApr 20 2013We explore the mid-infrared (mid-IR) through ultraviolet (UV) spectral energy distributions (SEDs) of 119,652 luminous broad-lined quasars with 0.064<z<5.46 using mid-IR data from Spitzer and WISE, near-infrared data from Two Micron All Sky Survey and ... More
The Clustering of High-Redshift (2.9 $\leq$ z $\leq$ 5.1) Quasars in SDSS Stripe 82Dec 08 2017May 17 2018We present a measurement of the two-point autocorrelation function of photometrically-selected, high-$z$ quasars over $\sim$ 100 deg$^2$ on the Sloan Digitial Sky Survey Stripe 82 field. Selection is performed using three machine-learning algorithms, ... More
A Simple Likelihood Method for Quasar Target SelectionApr 26 2011Sep 02 2011We present a new method for quasar target selection using photometric fluxes and a Bayesian probabilistic approach. For our purposes we target quasars using Sloan Digital Sky Survey (SDSS) photometry to a magnitude limit of g=22. The efficiency and completeness ... More
Mining for Dust in Type 1 QuasarsDec 22 2014Jun 02 2015We explore the extinction/reddening of ~35,000 uniformly selected quasars with 0<z<5.3 in order to better understand their intrinsic optical/ultraviolet spectral energy distributions. Using rest-frame optical-UV photometry taken from the Sloan Digital ... More
FIRST-2MASS Red Quasars: Transitional Objects Emerging from the DustJul 09 2012We present a sample of 120 dust-reddened quasars identified by matching radio sources detected at 1.4 GHz in the FIRST survey with the near-infrared 2MASS catalog and color-selecting red sources. Optical and/or near-infrared spectroscopy provide broad ... More
Discovery of extreme [OIII]5007A outflows in high-redshift red quasarsDec 08 2015Mar 23 2016Black hole feedback is now a standard component of galaxy formation models. These models predict that the impact of black hole activity on its host galaxy likely peaked at z=2-3, the epoch of strongest star formation activity and black hole accretion ... More
Spectropolarimetry of High Redshift Obscured and Red QuasarsJun 26 2018Spectropolarimetry is a powerful technique that has provided critical support for the geometric unification model of local active galactic nuclei. In this paper, we present optical (rest-frame UV) Keck spectropolarimetry of five luminous obscured (Type ... More
Shubnikov-de Haas quantum oscilations reveal a reconstructed Fermi surface near optimal doping in a thin film of the cuprate superconductor Pr$_{1.86}$Ce$_{0.14}$CuO$_{4\pmδ}$Sep 03 2016We study magnetotransport properties of the electron-doped superconductor Pr$_{2-x}$Ce$_x$CuO$_{4\pm\delta}$ with $x$ = 0.14 in magnetic fields up to 92~T, and observe Shubnikov de-Haas magnetic quantum oscillations. The oscillations display a single ... More
Quasar Classification Using Color and VariabilityAug 17 2015We conduct a pilot investigation to determine the optimal combination of color and variability information to identify quasars in current and future multi-epoch optical surveys. We use a Bayesian quasar selection algorithm (Richards et al. 2004) to identify ... More
Quantum oscillations suggest hidden quantum phase transition in the cuprate superconductor Pr$_{2}$CuO$_{4\pmδ}$Oct 14 2015For both electron- and hole-doped cuprates, superconductivity appears in the vicinity of suppressed broken symmetry order, suggesting that quantum criticality plays a vital role in the physics of these systems. A confounding factor in identifying the ... More
Recalibration of Data in the VDFS Science ArchivesNov 01 2007The VDFS comprises the system to pipeline process and archive the data from infrared observations taken by both the WFCAM instrument on UKIRT and the forthcoming VISTA telescope. These include the largest near-IR surveys to date, such as UKIDSS, which ... More
A new model for archiving synoptic data in the VISTA Data Flow SystemJan 23 2009The VISTA Data Flow System comprises nightly pipeline and archiving of near infrared data from UKIRT-WFCAM and VISTA. This includes multi-epoch data which can be used to find moving and variable objects. We have developed a new model for archiving these ... More
Sloan Digital Sky Survey III Photometric Quasar Clustering: Probing the Initial Conditions of the Universe using the Largest VolumeNov 11 2013Mar 25 2015The Sloan Digital Sky Survey has surveyed 14,555 square degrees of the sky, and delivered over a trillion pixels of imaging data. We present the large-scale clustering of 1.6 million quasars between z = 0.5 and z = 2.5 that have been classified from this ... More
Sequences of stable bundles over a compact complex surfaceMay 05 1995When identified with sequences of irreducible Hermitian-Einstein connections, sequences of stable holomorphic bundles of fixed topological type and bounded degree on a compact complex surface equipped with a Gauduchon metric are shown to have strongly ... More
Blowups and gauge fieldsMay 05 1995The relationship between stable holomorphic vector bundles on a compact complex surface and the same such objects on a blowup of the surface is investigated, where "stability" is with respect to a Gauduchon metric on the surface and naturally derived ... More
Broad Absorption Line Variability on Multi-Year Timescales in a Large Quasar SampleSep 20 2013We present a detailed investigation of the variability of 428 C IV and 235 Si IV Broad Absorption Line (BAL) troughs identified in multi-epoch observations of 291 quasars by the Sloan Digital Sky Survey-I/II/III. These observations primarily sample rest-frame ... More
The Dependence of C IV Broad Absorption Line Properties on Accompanying Si IV and Al III Absorption: Relating Quasar-Wind Ionization Levels, Kinematics, and Column DensitiesJul 08 2014We consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the line-of-sight intercepts ... More
Weighted projective embeddings, stability of orbifolds and constant scalar curvature Kähler metricsJul 30 2009Sep 25 2009We embed polarised orbifolds with cyclic stabiliser groups into weighted projective space via a weighted form of Kodaira embedding. Dividing by the (non-reductive) automorphisms of weighted projective space then formally gives a moduli space of orbifolds. ... More
Bulk Stabilization, the Extra-Dimensional Higgs Portal and Missing Energy in Higgs EventsFeb 26 2013To solve the hierarchy problem, extra-dimensional models must explain why the new dimensions stabilize to the right size, and the known mechanisms for doing so require bulk scalars that couple to the branes. Because of these couplings the energetics of ... More
An obstruction to the existence of constant scalar curvature Kähler metricsDec 29 2004Dec 05 2005We prove that polarised manifolds that admit a constant scalar curvature K\"ahler (cscK) metric satisfy a condition we call slope semistability. That is, we define the slope $\mu$ for a projective manifold and for each of its subschemes, and show that ... More
Variability selected high-redshift quasars on SDSS Stripe 82Dec 10 2010Apr 16 2011The SDSS-III BOSS Quasar survey will attempt to observe z>2.15 quasars at a density of at least 15 per square degree to yield the first measurement of the Baryon Acoustic Oscillations in the Ly-alpha forest. To help reaching this goal, we have developed ... More
A study of the Hilbert-Mumford criterion for the stability of projective varietiesDec 29 2004Feb 02 2005We make a systematic study of the Hilbert-Mumford criterion for different notions of stability for polarised algebraic varieties $(X,L)$; in particular for K- and Chow stability. For each type of stability this leads to a concept of slope $\mu$ for varieties ... More
Weighted Bergman kernels on orbifoldsJul 30 2009Sep 16 2011We describe a notion of ampleness for line bundles on orbifolds with cyclic quotient singularities that is related to embeddings in weighted projective space, and prove a global asymptotic expansion for a weighted Bergman kernel associated to such a line ... More
The z=5 Quasar Luminosity Function from SDSS Stripe 82Dec 18 2012Apr 22 2013We present a measurement of the Type I quasar luminosity function at z=5 using a large sample of spectroscopically confirmed quasars selected from optical imaging data. We measure the bright end (M_1450<-26) with Sloan Digital Sky Survey (SDSS) data covering ... More
Black hole growth and host galaxy morphologyFeb 07 2010We use data from large surveys of the local Universe (SDSS+Galaxy Zoo) to show that the galaxy-black hole connection is linked to host morphology at a fundamental level. The fraction of early-type galaxies with actively growing black holes, and therefore ... More
Think Outside the Color Box: Probabilistic Target Selection and the SDSS-XDQSO Quasar Targeting CatalogNov 29 2010Mar 01 2011We present the SDSS-XDQSO quasar targeting catalog for efficient flux-based quasar target selection down to the faint limit of the Sloan Digital Sky Survey (SDSS) catalog, even at medium redshifts (2.5 <~ z <~ 3) where the stellar contamination is significant. ... More
The VISTA Science ArchiveOct 10 2012Dec 04 2012We describe the VISTA Science Archive (VSA) and its first public release of data from five of the six VISTA Public Surveys. The VSA exists to support the VISTA Surveys through their lifecycle: the VISTA Public Survey consortia can use it during their ... More
Constraint on neutrino masses from SDSS-III/BOSS Ly$α$ forest and other cosmological probesOct 27 2014Jan 12 2015We present constraints on the parameters of the $\Lambda$CDM cosmological model in the presence of massive neutrinos, using the one-dimensional Ly$\alpha$ forest power spectrum obtained with the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan ... More
The large-scale cross-correlation of Damped Lyman Alpha Systems with the Lyman Alpha Forest: First Measurements from BOSSSep 20 2012Dec 02 2012We present the first measurement of the large-scale cross-correlation of Lyman alpha forest absorption and Damped Lyman alpha systems (DLA), using the 9th Data Release of the Baryon Oscillation Spectroscopic Survey (BOSS). The cross-correlation is clearly ... More
Clustering of Low-Redshift (z <= 2.2) Quasars from the Sloan Digital Sky SurveyMar 18 2009We present measurements of the quasar two-point correlation function, \xi_{Q}, over the redshift range z=0.3-2.2 based upon data from the SDSS. Using a homogeneous sample of 30,239 quasars with spectroscopic redshifts from the DR5 Quasar Catalogue, our ... More
Cataclysmic Variables from SDSS. VIII. The Final Year (2007-2008)Sep 28 2011This paper completes the series of cataclysmic variables (CVs) identified from the Sloan Digital Sky Survey I/II. The coordinates, magnitudes and spectra of 33 CVs are presented. Among the 33 are eight systems known previous to SDSS (CT Ser, DO Leo, HK ... More
Extremely Red Quasars from SDSS, BOSS and WISE: Classification of Optical SpectraMay 05 2014Feb 27 2016Quasars with extremely red infrared-to-optical colours are an interesting population that can test ideas about quasar evolution as well as orientation, obscuration and geometric effects in the so-called AGN unified model. To identify such a population ... More
A glance at the host galaxy of high-redshift quasars using strong damped Lyman-alpha systems as coronagraphsAug 12 2013We searched quasar spectra from the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) for the rare occurrences where a strong damped Lyman-alpha absorber (DLA) blocks the Broad Line Region emission from the quasar and acts as a natural coronagraph ... More
The large-scale Quasar-Lyman α Forest Cross-Correlation from BOSSMar 08 2013Sep 02 2013We measure the large-scale cross-correlation of quasars with the Lyman \alpha\ forest absorption in redshift space, using ~ 60000 quasar spectra from Data Release 9 (DR9) of the Baryon Oscillation Spectroscopic Survey (BOSS). The cross-correlation is ... More
The 2dF-SDSS LRG and QSO Survey: the QSO luminosity function at 0.4<z<2.6Jul 16 2009We present the QSO luminosity function of the completed 2dF-SDSS LRG and QSO (2SLAQ) survey, based on QSOs photometrically selected from Sloan Digital Sky Survey imaging data and then observed spectroscopically using the 2dF instrument on the Anglo-Australian ... More
Near Infrared Spectra and Intrinsic Luminosities of Candidate Type II Quasars at 2 < z < 3.4Apr 14 2014We present JHK near-infrared (NIR) spectroscopy of 25 candidate Type II quasars selected from the Sloan Digital Sky Survey, using Triplespec on the Apache Point Observatory 3.5m telescope, FIRE at the Magellan/Baade 6.5m telescope, and GNIRS on Gemini. ... More
Candidate Type II Quasars at 2 < z < 4.3 in the Sloan Digital Sky Survey IIIJul 27 2013Aug 09 2013At low redshifts, dust-obscured quasars often have strong yet narrow permitted lines in the rest-frame optical and ultraviolet, excited by the central active nucleus, earning the designation Type II quasars. We present a sample of 145 candidate Type II ... More
A Systematic Search for Changing-Look Quasars in SDSSSep 28 2015Jan 04 2016We present a systematic search for changing-look quasars based on repeat photometry from SDSS and Pan-STARRS1, along with repeat spectra from SDSS and SDSS-III BOSS. Objects with large, |\Delta g|>1 mag photometric variations in their light curves are ... More
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: measuring structure growth using passive galaxiesMar 29 2012Jun 22 2012We explore the benefits of using a passively evolving population of galaxies to measure the evolution of the rate of structure growth between z=0.25 and z=0.65 by combining data from the SDSS-I/II and SDSS-III surveys. The large-scale linear bias of a ... More
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: weighing the neutrino mass using the galaxy power spectrum of the CMASS sampleNov 15 2012Mar 10 2014We measure the sum of the neutrino particle masses using the three-dimensional galaxy power spectrum of the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 9 (DR9) CMASS galaxy sample. Combined with the cosmic microwave background ... More
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in the correlation function of LOWZ and CMASS galaxies in Data Release 12Sep 21 2015Jan 11 2016We present distance scale measurements from the baryon acoustic oscillation signal in the CMASS and LOWZ samples from the Data Release 12 of the Baryon Oscillation Spectroscopic Survey (BOSS). The total volume probed is 14.5 Gpc$^3$, a 10 per cent increment ... More
The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Anisotropic galaxy clustering in Fourier-spaceJul 11 2016We investigate the anisotropic clustering of the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 (DR12) sample, which consists of $1\,198\,006$ galaxies in the redshift range $0.2 < z < 0.75$ and a sky coverage of $10\,252\,$deg$^2$. We ... More
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Signs of neutrino mass in current cosmological datasetsMar 18 2014Sep 03 2014We investigate the cosmological implications of the latest growth of structure measurement from the Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Data Release 11 with particular focus on the sum of the neutrino masses, $\sum m_{\nu}$. We examine ... More
Extremely Red Quasars in BOSSSep 23 2016Red quasars are candidate young objects in an early transition stage of massive galaxy evolution. Our team recently discovered a population of extremely red quasars (ERQs) in the Baryon Oscillation Spectroscopic Survey (BOSS) that has a suite of peculiar ... More
A Mid-IR Selected Changing-Look Quasar and Physical Scenarios for Abrupt AGN FadingMay 17 2018We report a new changing-look quasar, WISE~J105203.55+151929.5 at $z=0.303$, found by identifying highly mid-IR variable quasars in the WISE/NEOWISE data stream. Compared to multi-epoch mid-IR photometry of a large sample of SDSS-confirmed quasars, WISE ... More
AGN (and other) astrophysics with Gravitational Wave EventsMar 22 2019The stellar mass binary black hole (sBBH) mergers presently detected by LIGO may originate wholly or in part from binary black hole mergers embedded in disks of gas around supermassive black holes. Determining the contribution of these active galactic ... More
New Neutrino Mass Bounds from Sloan Digital Sky Survey III Data Release 8 Photometric Luminous GalaxiesJan 09 2012We present neutrino mass bounds using 900,000 luminous galaxies with photometric redshifts measured from Sloan Digital Sky Survey III Data Release Eight (SDSS DR8). The galaxies have photometric redshifts between $z = 0.45$ and $z = 0.65$, and cover 10,000 ... More
Bayesian High-Redshift Quasar Classification from Optical and Mid-IR PhotometryJul 28 2015We identify 885,503 type 1 quasar candidates to i<22 using the combination of optical and mid-IR photometry. Optical photometry is taken from the Sloan Digital Sky Survey-III: Baryon Oscillation Spectroscopic Survey (SDSS-III/BOSS), while mid-IR photometry ... More
A new physical interpretation of optical and infrared variability in quasarsMay 17 2018Sep 27 2018Changing-look quasars are a recently identified class of active galaxies in which the strong UV continuum and/or broad optical hydrogen emission lines associated with unobscured quasars either appear or disappear on timescales of months to years. The ... More
Shear to longitudinal mode conversion via second harmonic generation in a two-dimensional microscale granular crystalFeb 15 2016Shear to longitudinal mode conversion via second harmonic generation is studied theoretically and computationally for plane waves in a two-dimensional, adhesive, hexagonally close-packed microscale granular medium. The model includes translational and ... More
Superstratum SymbiosisMar 18 2019Superstrata are smooth horizonless microstate geometries for the supersymmetric D1-D5-P black hole in type IIB supergravity. In the CFT, 'superstratum states' are defined to be the component of the supergraviton gas that is obtained by breaking the CFT ... More
Resolving the Structure of Black Holes: Philosophizing with a HammerNov 18 2013We give a broad conceptual review of what we have learned about black holes and their microstate structure from the study of microstate geometries and their string theory limits. We draw upon general relativity, supergravity, string theory and holographic ... More
Observation of the ghost critical field for superconducting fluctuations in a disordered TaN thin filmMar 03 2013Oct 07 2013We experimentally study the ghost critical field (GCF), a magnetic field scale for the suppression of superconducting fluctuations, using Hall effect and magnetoresistance measurements on a disordered superconducting thin film near its transition temperature ... More
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Testing gravity with redshift-space distortions using the power spectrum multipolesDec 17 2013Jun 28 2014We analyse the anisotropic clustering of the Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Data Release 11 (DR11) sample, which consists of $690\,827$ galaxies in the redshift range $0.43 < z < 0.7$ and has a sky coverage of $8\,498\,\text{deg}^2$. ... More
Automated curation of infra-red imaging data in the WFCAM and VISTA Science ArchivesDec 18 2010The two fastest near infrared survey telescopes are UKIRT-WFCAM and VISTA. The data from both these instruments are being archived by Wide Field Astronomy Unit (WFAU) at the IfA, Edinburgh, using the same curation pipeline, with some instrument specific ... More
Smart Wireless Communication is the Cornerstone of Smart InfrastructuresJun 22 2017Emerging smart infrastructures, such as Smart City, Smart Grid, Smart Health, and Smart Transportation, need smart wireless connectivity. However, the requirements of these smart infrastructures cannot be met with today's wireless networks. A new wireless ... More
A pseudo-parallel Python environment for database curationNov 13 2007One of the major challenges providing large databases like the WFCAM Science Archive (WSA) is to minimize ingest times for pixel/image metadata and catalogue data. In this article we describe how the pipeline processed data are ingested into the database ... More
Sensitivity of the interlayer magnetoresistance of layered metals to intralayer anisotropiesOct 06 2006Aug 21 2007Many of the most interesting and technologically important electronic materials discovered in the past two decades have two common features: a layered crystal structure and strong interactions between electrons. Two of the most fundamental questions about ... More
Dynamics of nanoscale bubbles growing in a tapered conduitDec 09 2017We predict the dynamics and shapes of nanobubbles growing in a supersaturated solution confined within a tapered, Hele-Shaw device with a small opening angle $\Phi \ll 1$. Our study is inspired by experimental observations of the growth and translation ... More
Quantum interference and weak localisation effects in the interlayer magnetoresistance of layered metalsApr 09 2008Studies of angle-dependent magnetoresistance oscillations (AMRO) in the interlayer conductivity of layered metals have generally considered semi-classical electron transport. We consider a quantum correction to the semi-classical conductivity that arises ... More
Butterflies with rotation and chargeApr 14 2016We explore the butterfly effect for black holes with rotation or charge. We perturb rotating BTZ and charged black holes in 2+1 dimensions by adding a small perturbation on one asymptotic region, described by a shock wave in the spacetime, and explore ... More
Complexity of the AdS SolitonDec 11 2017We consider the holographic complexity conjectures in the context of the AdS soliton, which is the holographic dual of the ground state of a field theory on a torus with antiperiodic boundary conditions for fermions on one cycle. The complexity is a non-trivial ... More
Broad Absorption Line Disappearance on Multi-Year Timescales in a Large Quasar SampleAug 03 2012We present 21 examples of C IV Broad Absorption Line (BAL) trough disappearance in 19 quasars selected from systematic multi-epoch observations of 582 bright BAL quasars (1.9 < z < 4.5) by the Sloan Digital Sky Survey-I/II (SDSS-I/II) and SDSS-III. The ... More
The Clustering of Galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS): measuring growth rate and geometry with anisotropic clusteringDec 17 2013May 13 2014We use the observed anisotropic clustering of galaxies in the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 11 CMASS sample to measure the linear growth rate of structure, the Hubble expansion rate and the comoving distance scale. Our sample ... More
The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in Fourier-spaceJul 11 2016We analyse the Baryon Acoustic Oscillation (BAO) signal of the final Baryon Oscillation Spectroscopic Survey (BOSS) data release (DR12). Our analysis is performed in Fourier-space, using the power spectrum monopole and quadrupole. The dataset includes ... More
Supersymmetric Janus Solutions in Four DimensionsNov 19 2013We use maximal gauged supergravity in four dimensions to construct the gravity dual of a class of supersymmetric conformal interfaces in the theory on the world-volume of multiple M2-branes. We study three classes of examples in which the $(1+1)$-dimensional ... More
The Bivariate Brightness Function of Galaxies and a Demonstration of the Impact of Surface Brightness Selection Effects on Luminosity Function EstimationsOct 17 2001In this paper we fit an analytic function to the Bivariate Brightness Distribution (BBD) of galaxies. It is a combination of the classical Schechter Function convolved with a Gaussian distribution in surface brightness: thus incorporating the luminosity-surface ... More
A Dynamical Potential-Density Pair for Star Clusters With Nearly Isothermal InteriorsMar 11 2015Jul 02 2015We present a potential-density pair designed to model nearly isothermal star clusters (and similar self-gravitating systems) with a central core and an outer turnover radius, beyond which density falls off as $r^{-4}$. In the intermediate zone, the profile ... More
Imaginary Soaring Branes: A Hidden Feature of Non-Extremal SolutionsMay 31 2011A key property of many BPS solutions of supergravity is the fact that certain probe branes placed in these solutions feel no force, essentially because electric repulsion and gravitational attraction balance one another. In this letter we show that the ... More
Parallel Algorithms for Constrained Tensor Factorization via the Alternating Direction Method of MultipliersSep 08 2014May 05 2015Tensor factorization has proven useful in a wide range of applications, from sensor array processing to communications, speech and audio signal processing, and machine learning. With few recent exceptions, all tensor factorization algorithms were originally ... More
Faraday Conversion in Turbulent Blazar JetsNov 30 2016Jul 05 2018Low ($\lesssim 1\%$) levels of circular polarization (CP) detected at radio frequencies in the relativistic jets of some blazars can provide insight into the underlying nature of the jet plasma. CP can be produced through linear birefringence, in which ... More
Infinite Excess Entropy Processes with Countable-State GeneratorsNov 14 2011We present two examples of finite-alphabet, infinite excess entropy processes generated by invariant hidden Markov models (HMMs) with countable state sets. The first, simpler example is not ergodic, but the second is. It appears these are the first constructions ... More
Tidal Stresses and Energy Gaps in Microstate GeometriesOct 24 2017We compute energy gaps and study infalling massive geodesic probes in the new families of scaling, microstate geometries that have been constructed recently and for which the holographic duals are known. We find that in the deepest geometries, which have ... More
Release angle for attaining maximum distance in the soccer throw-inJan 20 2006We investigated the release angle that maximises the distance attained in a long soccer throw-in. One male soccer player performed maximum-effort throws using release angles of between 10 and 60 degrees, and the throws were analysed using 2-D video. The ... More
Black Rings in Taub-NUTApr 18 2005We construct the most generic three-charge, three-dipole-charge, BPS black-ring solutions in a Taub-NUT background. These solutions depend on seven charges and six moduli, and interpolate between a four-dimensional black hole and a five-dimensional black ... More
On Supersymmetric Flux Solutions of M-theoryJul 18 2012Motivated by the geometric structures of supersymmetric holographic RG-flows, we scan for N=2 AdS_4 solutions in M-theory. One particularly well understood holographic RG flow in M-theory is dual to a mass deformation of the N=8 Chern-Simons theory. We ... More
Partition asymptotics from one-dimensional quantum entropy and energy currentsSep 19 2000Dec 11 2001We give an alternative method to that of Hardy-Ramanujan-Rademacher to derive the leading exponential term in the asymptotic approximation to the partition function p(n,a), defined as the number of decompositions of a positive integer 'n' into integer ... More
New Supersymmetric and Stable, Non-Supersymmetric Phases in Supergravity and Holographic Field TheoryOct 23 2010We establish analytically that the potential of N=8 supergravity in four dimensions has a new N=1 supersymmetric critical point with U(1) x U(1) symmetry. We work within a consistent N=1 supersymmetric truncation and obtain the holographic flow to this ... More
The suppression of hidden order and onset of ferromagnetism in URu2Si2 via Re substitutionApr 05 2010Substitution of Re for Ru in the heavy fermion compound URu2Si2 suppresses the hidden order transition and gives rise to ferromagnetism at higher concentrations. The hidden order transition of URu(2-x)Re(x)Si2, tracked via specific heat and electrical ... More
Equivalence of History and Generator Epsilon-MachinesNov 18 2011Dec 14 2012Epsilon-machines are minimal, unifilar presentations of stationary stochastic processes. They were originally defined in the history machine sense, as hidden Markov models whose states are the equivalence classes of infinite pasts with the same probability ... More
Asymptotic Synchronization for Finite-State SourcesNov 06 2010Jan 03 2011We extend a recent synchronization analysis of exact finite-state sources to nonexact sources for which synchronization occurs only asymptotically. Although the proof methods are quite different, the primary results remain the same. We find that an observer's ... More
The Structure of BPS Equations for Ambi-polar Microstate GeometriesJul 17 2018Sep 11 2018Ambi-polar metrics, defined so as to allow the signature to change from +4 to -4 across hypersurfaces, are a mainstay in the construction of BPS microstate geometries. This paper elucidates the cohomology of these spaces so as to simplify greatly the ... More
Protoplanetary Disk Masses from Radiative Transfer Modeling: A Case Study in TaurusMar 19 2019Measuring the masses of protoplanetary disks is crucial for understanding their planet-forming potential. Typically, dust masses are derived from (sub-)millimeter flux density measurements plus assumptions for the opacity, temperature, and optical depth ... More
SpIES: The Spitzer IRAC Equatorial SurveyMar 28 2016We describe the first data release from the Spitzer-IRAC Equatorial Survey (SpIES); a large-area survey of 115 deg^2 in the Equatorial SDSS Stripe 82 field using Spitzer during its 'warm' mission phase. SpIES was designed to probe sufficient volume to ... More
Exact Synchronization for Finite-State SourcesAug 25 2010Jan 03 2011We analyze how an observer synchronizes to the internal state of a finite-state information source, using the epsilon-machine causal representation. Here, we treat the case of exact synchronization, when it is possible for the observer to synchronize ... More
$\mathcal{N}=2$ Supersymmetric Janus Solutions and Flows: From Gauged Supergravity to M TheoryOct 27 2015We investigate a family of SU(3)$\times$U(1)$\times$U(1)-invariant holographic flows and Janus solutions obtained from gauged $\mathcal{N}=8$ supergravity in four dimensions. We give complete details of how to use the uplift formulae to obtain the corresponding ... More
Effective Superpotentials, Geometry and Integrable SystemsDec 07 2003We consider the effective superpotentials of N=1 SU(N_c) and U(N_c) supersymmetric gauge theories that are obtained from the N=2 theory by adding a tree-level superpotential. We show that several of the techniques for computing the effective superpotential ... More
Probing the Circumgalactic Medium at High-Redshift Using Composite BOSS Spectra of Strong Lyman-alpha Forest AbsorbersSep 26 2013Mar 20 2014We present composite spectra constructed from a sample of 242,150 Lyman-alpha (Lya) forest absorbers at redshifts 2.4<z<3.1 identified in quasar spectra from the Baryon Oscillation Spectroscopic Survey (BOSS) as part of Data Release 9 of the Sloan Digital ... More
Active Disassembly and Reassembly of Actin Networks Induces Distinct Biphasic MechanicsOct 10 2017Actin is a key component of the cytoskeleton, which plays central roles in cell motility, division, growth, and tensile strength. To enable this wide range of transient mechanical processes and properties, networks of actin filaments continuously disassemble ... More