Results for "Roberto J. Assef"

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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
A Multi-Wavelength Study of Low Redshift Clusters of Galaxies I. Comparison of X-ray and Mid-Infrared Selected AGNsJan 04 2011Clusters of galaxies have long been used as laboratories for the study of galaxy evolution, but despite intense, recent interest in feedback between AGNs and their hosts, the impact of environment on these relationships remains poorly constrained. We ... More
CIV Line-Width Anomalies: The Perils of Low S/N SpectraMar 15 2013Aug 27 2013Comparison of six high-redshift quasar spectra obtained with the Large Binocular Telescope with previous observations from the Sloan Digital Sky Survey shows that failure to correctly identify absorption and other problems with accurate characterization ... More
Extending the Calibration of CIV-Based Single-Epoch Black Hole Mass Estimators for Active Galactic NucleiMar 29 2017We provide an updated calibration of CIV $\lambda1549$ broad emission line-based single-epoch (SE) black hole (BH) mass estimators for active galactic nuclei (AGNs) using new data for six reverberation-mapped AGNs at redshift $z=0.005-0.028$ with BH masses ... More
A Kiloparsec-Scale Binary Active Galactic Nucleus Confirmed by the Expanded Very Large ArrayAug 31 2011Sep 13 2011We report the confirmation of a kpc-scale binary active galactic nucleus (AGN) with high-resolution radio images from the Expanded Very Large Array (EVLA). SDSS J150243.1+111557 is a double-peaked [O III] AGN at z = 0.39 selected from the Sloan Digital ... More
Optical Spectroscopic Survey of High Latitude WISE Selected SourcesNov 01 2011Nov 03 2011We report on the results of an optical spectroscopic survey at high Galactic latitude (b\geq30{\deg}) of a sample of WISE-selected targets, grouped by WISE W1 ({\lambda}_eff = 3.4 \mum) flux, which we use to characterize the sources WISE detected. We ... More
A UV to Mid-IR Study of AGN SelectionFeb 21 2014We classify the spectral energy distributions (SEDs) of 431,038 sources in the 9 sq. deg Bootes field of the NOAO Deep Wide-Field Survey (NDWFS). There are up to 17 bands of data available per source, including ultraviolet (GALEX), optical (NDWFS), near-IR ... More
The Origin of the 24-micron Excess in Red GalaxiesNov 10 2008Nov 17 2008Observations with the Spitzer Space Telescope have revealed a population of red-sequence galaxies with a significant excess in their 24-micron emission compared to what is expected from an old stellar population. We identify 900 red galaxies with 0.15<z<0.3 ... More
A Candidate Dual AGN at z=1.175Sep 15 2011The X-ray source CXOXBJ142607.6+353351 (CXOJ1426+35), which was identified in a 172 ks Chandra image in the Bootes field, shows double-peaked rest-frame optical/UV emission lines, separated by 0.69" (5.5 kpc) in the spatial dimension and by 690 km s^-1 ... More
Interferometric Follow-Up of WISE Hyper-Luminous Hot, Dust-Obscured GalaxiesMay 06 2014Jul 29 2014WISE has discovered an extraordinary population of hyper-luminous dusty galaxies which are faint in the two bluer passbands ($3.4\, \mu$m and $4.6\, \mu$m) but are bright in the two redder passbands of WISE ($12\, \mu$m and $22\, \mu$m). We report on ... More
Mid-Infrared Selection of Active Galactic Nuclei with the Wide-Field Infrared Survey Explorer. II. Properties of WISE-Selected Active Galactic Nuclei in the NDWFS Boötes FieldSep 26 2012May 23 2013Stern et al.(2012) presented a study of WISE selection of AGN in the 2 deg^2 COSMOS field, finding that a simple criterion W1-W2>=0.8 provides a highly reliable and complete AGN sample for W2<15.05, where the W1 and W2 passbands are centered at 3.4 and ... 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
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
Half of the Most Luminous Quasars May Be Obscured: Investigating the Nature of WISE-Selected Hot, Dust-Obscured GalaxiesAug 05 2014Feb 19 2015The WISE mission has unveiled a rare population of high-redshift ($z=1-4.6$), dusty, hyper-luminous galaxies, with infrared luminosities $L_{\rm IR} > 10^{13}~L_{\odot}$, and sometimes exceeding $10^{14}~L_{\odot}$. Previous work has shown that their ... More
Submillimetre observations of WISE/radio-selected AGN and their environmentsMar 09 2015We present JCMT SCUBA-2 850microns submillimetre (submm) observations of 30 mid-infrared (mid-IR) luminous AGN, detected jointly by the WISE all-sky IR survey and the NVSS/FIRST radio survey. These rare sources are selected by their extremely red mid-infrared ... More
Submillimetre observations of WISE-selected high-redshift, luminous, dusty galaxiesJun 10 2014We present SCUBA-2 850um submillimetre (submm) observations of the fields of 10 dusty, luminous galaxies at z ~ 1.7 - 4.6, detected at 12um and/or 22um by the WISE all-sky survey, but faint or undetected at 3.4um and 4.6um; dubbed hot, dust-obscured galaxies ... More
Eddington-Limited Accretion in z~2 WISE-selected Hot, Dust-Obscured GalaxiesMar 20 2017Dec 06 2017Hot, Dust-Obscured Galaxies, or "Hot DOGs", are a rare, dusty, hyperluminous galaxy population discovered by the WISE mission. Predominantly at redshifts 2-3, they include the most luminous known galaxies in the universe. Their high luminosities likely ... More
High redshift extremely red quasars in X-raysFeb 12 2018Quasars may have played a key role in limiting the stellar mass of massive galaxies. Identifying those quasars in the process of removing star formation fuel from their hosts is an exciting ongoing challenge in extragalactic astronomy. In this paper we ... More
Extending the Nearby Galaxy Heritage with WISE: First Results from the WISE Enhanced Resolution Galaxy AtlasOct 12 2012Oct 26 2012The Wide-field Infrared Survey Explorer (WISE) mapped the entire sky at mid-infrared wavelengths 3.4, 4.6, 12 and 22 microns. The mission was primarily designed to extract point sources, leaving resolved and extended sources unexplored. We have begun ... More
Overdensities of SMGs around WISE-selected, ultra-luminous, high-redshift AGNMay 10 2017We investigate extremely luminous dusty galaxies in the environments around WISE-selected hot dust obscured galaxies (Hot DOGs) and WISE/radio-selected active galactic nuclei (AGNs) at average redshifts of z = 2.7 and z = 1.7, respectively. Previous observations ... More
Low Resolution Spectral Templates for AGNs and GalaxiesApr 29 2010We present a set of low resolution empirical SED templates for AGNs and galaxies in the wavelength range from 0.03 to 30 microns. These templates form a non-negative basis of the color space of such objects and have been derived from a combination 14448 ... More
The Angular Clustering of WISE-Selected AGN: Different Haloes for Obscured and Unobscured AGNSep 09 2013Apr 16 2014We calculate the angular correlation function for a sample of 170,000 AGN extracted from the Wide-field Infrared Survey Explorer (WISE) catalog, selected to have red mid-IR colors (W1 - W2 > 0.8) and 4.6 micron flux densities brighter than 0.14 mJy). ... More
Detecting Transits of Planetary Companions to Giant StarsFeb 24 2009Jun 23 2009Of the approximately 350 extrasolar planets currently known, of order 10% orbit evolved stars with radii R >~ 2.5 R_sun. These planets are of particular interest because they tend to orbit more massive hosts, and have been subjected to variable stellar ... More
The First Hyper-Luminous Infrared Galaxy Discovered by WISEAug 27 2012We report the discovery by the Wide-field Infrared Survey Explorer of the z = 2.452 source WISE J181417.29+341224.9, the first hyperluminous source found in the WISE survey. WISE 1814+3412 is also the prototype for an all-sky sample of ~1000 extremely ... More
WISE J233237.05-505643.5: a Double-Peaked Broad-Lined AGN with Spiral-Shaped Radio MorphologyOct 08 2013We present radio continuum mapping, optical imaging and spectroscopy of the newly discovered double-peaked broad-lined AGN WISE J233237.05-505643.5 at redshift z = 0.3447. This source exhibits an FR-I and FR-II hybrid-morphology, characterized by bright ... More
Clustering of obscured and unobscured quasars in the Bootes field: Placing rapidly growing black holes in the cosmic webFeb 23 2011We present the first measurement of the spatial clustering of mid-infrared selected obscured and unobscured quasars, using a sample in the redshift range 0.7 < z < 1.8 selected from the 9 deg^2 Bootes multiwavelength survey. Recently the Spitzer Space ... More
Radio Jet Feedback and Star Formation in Heavily Obscured Quasars at Redshifts ~0.3-3, I: ALMA ObservationsSep 01 2015Sep 14 2015We present ALMA 870 micron (345 GHz) data for 49 high redshift (0.47<z<2.85), luminous (11.7 < log L(bol) (Lsun) < 14.2) radio-powerful AGN, obtained to constrain cool dust emission from starbursts concurrent with highly obscured radiative-mode black ... More
A correlation between star formation rate and average black hole accretion in star forming galaxiesJun 05 2013We present a measurement of the average supermassive black hole accretion rate (BHAR) as a function of star formation rate (SFR) for galaxies in the redshift range 0.25<z<0.8. We study a sample of 1,767 far-IR selected star-forming galaxies in the 9 deg^2 ... More
NuSTAR Resolves the First Dual AGN above 10 keV in SWIFT J2028.5+2543Aug 22 2017We have discovered heavy obscuration in the dual active galactic nucleus (AGN) in the Swift/Burst Alert Telescope (BAT) source SWIFT J2028.5+2543 using Nuclear Spectroscopic Telescope Array (NuSTAR). While an early XMM-Newton study suggested the emission ... More
Constructing a WISE High Resolution Galaxy AtlasAug 01 2012After eight months of continuous observations, the Wide-field Infrared Survey Explorer (WISE) mapped the entire sky at 3.4 {\mu}m, 4.6 {\mu}m, 12 {\mu}m and 22 {\mu}m. We have begun a dedicated WISE High Resolution Galaxy Atlas (WHRGA) project to fully ... More
A Connection between Obscuration and Star Formation in Luminous QuasarsJan 20 2015We present a measurement of the star formation properties of a uniform sample of mid-IR selected, unobscured and obscured quasars (QSO1s and QSO2s) in the Bo\"otes survey region. We use an spectral energy distribution (SED) analysis for photometric data ... More
NuSTAR J163433-4738.7: A Fast X-ray Transient in the Galactic PlaneFeb 10 2014Mar 25 2014During hard X-ray observations of the Norma spiral arm region by the Nuclear Spectroscopic Telescope Array (NuSTAR) in 2013 February, a new transient source, NuSTAR J163433-4738.7, was detected at a significance level of 8-sigma in the 3-10 keV bandpass. ... More
The X-ray and Mid-Infrared luminosities in Luminous Type 1 QuasarsJan 18 2017Aug 21 2017Several recent studies have reported different intrinsic correlations between the AGN mid-IR luminosity ($L_{MIR}$) and the rest-frame 2-10 keV luminosity ($L_{X}$) for luminous quasars. To understand the origin of the difference in the observed $L_{X}-L_{MIR}$ ... More
NuSTAR and Keck Observations of Heavily Obscured Quasars Selected by WISENov 06 2018A primary aim of the Nuclear Spectroscopic Telescope Array (NuSTAR) mission is to find and characterize heavily obscured Active Galactic Nuclei (AGNs). Based on mid-infrared photometry from the Wide-Field Infrared Survey Explorer (WISE) and optical photometry ... More
Submillimeter Follow-up of WISE-Selected Hyperluminous GalaxiesAug 27 2012We have used the Caltech Submillimeter Observatory (CSO) to follow-up a sample of WISE-selected, hyperluminous galaxies, so called W1W2-dropout galaxies. This is a rare (~ 1000 all-sky) population of galaxies at high redshift (peaks at z=2-3), that are ... More
The UV--mid-IR Spectral Energy Distribution of a z=1.7 Quasar Host GalaxyApr 10 2009Jul 16 2009We have measured the spectral energy distribution (SED) of the host galaxy of the z_s=1.7 gravitationally lensed quasar SDSS J1004+4112 from 0.44-8.0 micron (0.16-3.0 micron in the rest frame). The large angular extent of the lensed images and their separation ... More
The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Evolution of the molecular gas in CO-selected galaxiesMar 21 2019We analyze the interstellar medium properties of a sample of sixteen bright CO line emitting galaxies identified in the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field (ASPECS) Large Program. This CO$-$selected galaxy sample is complemented by ... More
The ALMA Spectroscopic Survey in the HUDF: CO emission lines and 3 mm continuum sourcesMar 21 2019The ALMA SPECtroscopic Survey in the {\it Hubble} Ultra Deep Field is an ALMA large program that obtained a frequency scan in the 3\,mm band to detect emission lines from the molecular gas in distant galaxies. We here present our search strategy for emission ... More
Removing the Microlensing Blending-Parallax Degeneracy Using Source VariabilityApr 07 2006Sep 27 2006Microlensing event MACHO 97-SMC-1 is one of the rare microlensing events for which the source is a variable star, simply because most variable stars are systematically eliminated from microlensing studies. Using observational data for this event, we show ... More
Mid-Infrared Variability from the Spitzer Deep, Wide-Field SurveyFeb 18 2010May 28 2010We use the multi-epoch, mid-infrared Spitzer Deep, Wide-Field Survey to investigate the variability of 474,179 objects in 8.1 deg^2 of the NDWFS Bootes field. We perform a Difference Image Analysis of the four available epochs between 2004 and 2008, focusing ... More
The Lick AGN Monitoring Project 2011: Fe II Reverberation from the Outer Broad-Line RegionApr 16 2013The prominent broad Fe II emission blends in the spectra of active galactic nuclei have been shown to vary in response to continuum variations, but past attempts to measure the reverberation lag time of the optical Fe II lines have met with only limited ... More
Super-Eddington Accretion in the WISE-Selected Extremely Luminous Infrared Galaxy W2246-0526Oct 06 2018We use optical and near-infrared spectroscopy to observe rest-UV emission lines and estimate the black hole mass of WISEA J224607.56-052634.9 (W2246-0526) at z = 4.601, the most luminous hot dust-obscured galaxy yet discovered by WISE. From the broad ... More
ALMA spectroscopic survey in the Hubble Ultra Deep Field: CO luminosity functions and the evolution of the cosmic density of molecular gasJul 22 2016Sep 12 2016In this paper we use ASPECS, the ALMA Spectroscopic Survey in the {\em Hubble} Ultra Deep Field (UDF) in band 3 and band 6, to place blind constraints on the CO luminosity function and the evolution of the cosmic molecular gas density as a function of ... More
ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Survey DescriptionJul 22 2016We present the rationale for and the observational description of ASPECS: The ALMA SPECtroscopic Survey in the Hubble Ultra-Deep Field (UDF), the cosmological deep field that has the deepest multi-wavelength data available. Our overarching goal is to ... More
The Importance of Broad Emission-Line Widths in Single Epoch Black Hole Mass EstimatesMar 12 2012May 29 2012Estimates of the mass of super-massive black holes (BHs) in distant active galactic nuclei (AGNs) can be obtained efficiently only through single-epoch spectra, using a combination of their broad emission-line widths and continuum luminosities. Yet the ... More
The ALMA Spectroscopic Survey in the HUDF: CO luminosity functions and the molecular gas content of galaxies through cosmic historyMar 21 2019We use the results from the ALMA large program ASPECS, the spectroscopic survey in the Hubble Ultra Deep Field (HUDF), to constrain CO luminosity functions of galaxies and the resulting redshift evolution of $\rho$(H$_2$). The broad frequency range covered ... More
Evolution of the UV Excess in Early-Type GalaxiesJul 31 2008Feb 05 2009We examine the UV emission from luminous early-type galaxies as a function of redshift. We perform a stacking analysis using Galaxy Evolution Explorer (GALEX) images of galaxies in the NOAO Deep Wide Field Survey (NDWFS) Bo\"otes field and examine the ... More
The Lick AGN Monitoring Project 2011: Dynamical Modeling of the Broad Line Region in Mrk 50May 16 2012We present dynamical modeling of the broad line region (BLR) in the Seyfert 1 galaxy Mrk 50 using reverberation mapping data taken as part of the Lick AGN Monitoring Project (LAMP) 2011. We model the reverberation mapping data directly, constraining the ... More
The role of the most luminous, obscured AGN in galaxy assembly at z~2May 07 2017Jun 06 2017We present HST WFC3 F160W imaging and infrared spectral energy distributions for twelve extremely luminous, obscured AGN at $1.8<z<2.7$, selected via "Hot, Dust Obscured" mid-infrared colors. Their infrared luminosities span $2-15\times10^{13}$L$_{\odot}$, ... More
The Strikingly Uniform, Highly Turbulent Interstellar Medium of the Most Luminous Galaxy in the UniverseNov 12 2015Observed at z = 4.601 and with L_bol = 3.5 x 10^14 Lsun, W2246-0526 is the most luminous galaxy known in the Universe, and hosts a deeply-buried active galactic nucleus (AGN)/super-massive black hole (SMBH). Discovered using the Wide-field Infrared Survey ... More
Sums of squares in real quadratic fields and Hilbert modular groupsDec 27 2018We use the spectral theory of Hilbert-Maass forms for real quadratic fields to obtain the asymptotics of some sums involving the number of representations as a sum of two squares in the ring of integers.
The cosmological evolution of the QSO luminosity density and of the star formation rateOct 14 1997We demonstrate that the evolution of the QSO luminosity density with epoch displays a striking similarity to the cosmological evolution of the field galaxy star formation rate, recently derived from a number of independent surveys. The QSO luminosity ... More
Element sets for high-order Poincaré mapping of perturbed Keplerian motionOct 27 2018The propagation and Poincar\'e mapping of perturbed Keplerian motion is a key topic in celestial mechanics and astrodynamics, e.g. to study the stability of orbits or design bounded relative trajectories. The high-order transfer map (HOTM) method enables ... More
The 2.4 $μ$m Galaxy Luminosity Function as Measured Using WISE. II. Sample SelectionFeb 25 2017Sep 05 2018The WISE satellite surveyed the entire sky multiple times in four infrared (IR) wavelengths ($3.4,\ 4.6,\ 12,$ and $22\, \mu$m, Wright et al. 2010). This all-sky IR photometric survey makes it possible to leverage many of the large publicly available ... More
The 2.4 $μ$m Galaxy Luminosity Function as Measured Using WISE. III. Measurement ResultsFeb 25 2017Sep 05 2018The WISE satellite surveyed the entire sky multiple times in four infrared wavelengths (3.4, 4.6, 12, and $22\,\mu$m; Wright et al. 2010). The unprecedented combination of coverage area and depth gives us the opportunity to measure the luminosity function ... More
Active Galactic Nuclei: what's in a name?Jul 22 2017Active Galactic Nuclei (AGN) are energetic astrophysical sources powered by accretion onto supermassive black holes in galaxies, and present unique observational signatures that cover the full electromagnetic spectrum over more than twenty orders of magnitude ... More
Results from the Wide-field Infrared Survey Explorer (WISE) Future Uses Session at the WISE at 5 MeetingMay 08 2015During the "WISE at 5: Legacy and Prospects" conference in Pasadena, CA -- which ran from February 10 - 12, 2015 -- attendees were invited to engage in an interactive session exploring the future uses of the Wide-field Infrared Survey Explorer (WISE) ... More
Customer churn prediction in telecom using machine learning and social network analysis in big data platformApr 01 2019Customer churn is a major problem and one of the most important concerns for large companies. Due to the direct effect on the revenues of the companies, especially in the telecom field, companies are seeking to develop means to predict potential customer ... More
AGES: The AGN and Galaxy Evolution SurveyOct 19 2011The AGN and Galaxy Evolution Survey (AGES) is a redshift survey covering, in its standard fields, 7.7 square degrees of the Bootes field of the NOAO Deep Wide-Field Survey (NDWFS). The final sample consists of 23745 redshifts. There are well-defined galaxy ... More
Bare Quark Stars or Naked Neutron Stars ? The Case of RX J1856.5-3754Aug 19 2003Nov 21 2003In a cool neutron star (T < 1.e6 K) endowed with a rather high magnetic field (B > 1.e13 G), a phase transition may occur in the outermost layers. As a consequence the neutron star becomes `bare', i.e. no gaseous atmosphere sits on the top of the crust. ... More
A percolation model with continuously varying exponentsJul 28 2015This work analyzes a percolation model on the diamond hierarchical lattice (DHL), where the percolation transition is retarded by the inclusion of a probability of erasing specific connected structures. It has been inspired by the recent interest on the ... More
Eigenvalues of Hecke operators on Hilbert modular groupsDec 09 2009We consider cuspidal representations in spaces of automorphic forms for the congruence subgroup $\Gamma_0(I)$ of Hilbert modular groups for some number field $F$. To each such representation are associated the eigenvalue $\lambda_j$ of the Casimir operator ... More
Heavy X-ray obscuration in the most-luminous galaxies discovered by WISENov 30 2017Hot Dust-Obscured Galaxies (Hot DOGs) are hyperluminous ($L_{\mathrm{8-1000\,\mu m}}>10^{13}\,\mathrm{L_\odot}$) infrared galaxies with extremely high (up to hundreds of K) dust temperatures. The sources powering both their extremely high luminosities ... More
A Luminous Transient Event in a Sample of WISE-Selected Variable AGNJul 20 2018Nov 26 2018Recently Assef et al.(2018) presented two catalogs of AGN candidates over 30,093 deg^2 selected from the Wide-field Infrared Survey Explorer (WISE) observations. From their most reliable sample, Assef et al. (2018) identified 45 AGN candidates with the ... More
Universal Deformation Rings and Quivers of Finite Representation TypeApr 03 2016Let k be a field of arbitrary characteristic and let Q be a quiver of finite representation type. In this paper we prove that if M is an indecomposable kQ-module then the universal deformation ring of M over kQ is isomorphic to k.
qNoise: A generator of non-Gaussian colored noiseNov 28 2018We introduce a software generator for a class of \emph{colored} (self-correlated) and \emph{non-Gaussian} noise, whose statistics and spectrum depend upon only two parameters, $q$ and $\tau$. Inspired by Tsallis' nonextensive formulation of statistical ... More
Hot Dust-Obscured Galaxies with Excess Blue LightMay 10 2019Hot Dust-Obscured Galaxies (Hot DOGs) are among the most luminous galaxies in the Universe. Powered by highly obscured, possibly Compton-thick, active galactic nuclei (AGNs), Hot DOGs are characterized by SEDs that are very red in the mid-IR yet dominated ... More
Low Resolution Spectral Templates For Galaxies From 0.2 -- 10 micronsAug 10 2007Jan 09 2008We built an optimal basis of low resolution templates for galaxies over the wavelength range from 0.2 to 10 $\mu$m using a variant of the algorithm presented by Budavari et al. (2000). We derived them using eleven bands of photometry from the NDWFS, FLAMEX, ... More
Point defect dynamics in bcc metalsNov 27 2004We present an analysis of the time evolution of self-interstitial atom and vacancy (point defect) populations in pure bcc metals under constant irradiation flux conditions. Mean-field rate equations are developed in parallel to a kinetic Monte Carlo (kMC) ... More
Strong multiplicity one theorems for locally homogeneous spaces of compact typeApr 23 2018Let $G$ be a compact connected semisimple Lie group, let $K$ be a closed subgroup of $G$, let $\Gamma$ be a finite subgroup of $G$, and let $\tau$ be a finite dimensional representation of $K$. For $\pi$ in the unitary dual $\widehat G$ of $G$, denote ... More
On the predictability of Galileo disposal orbitsJan 21 2019The end-of-life disposal of Galileo satellites is needed to avoid collisions with operational spacecraft and to prevent the generation of space debris. Either disposal in stable graveyard orbits or disposal into the atmosphere exploiting eccentricity ... More
Representation equivalence for compact symmetric spaces spaces of real rank oneDec 22 2018Given $G/K$, an irreducible compact symmetric space of {real} rank one, we study conditions on a $K$-type $\tau$ so that $\tau$-isospectrality {between the spaces $\Gamma\backslash G/K$ and $\Gamma'\backslash G/K$} implies that $\Gamma$ and $\Gamma'$ ... More
Dark halo microphysics and massive black hole scaling relations in galaxiesSep 23 2014We investigate the black hole (BH) scaling relation in galaxies using a model in which the galaxy halo and central BH are a self-gravitating sphere of dark matter (DM) with an isotropic, adiabatic equation of state. The equipotential where the escape ... More
On the horizons in a viable vector-tensor theory of gravitationSep 10 2015A certain vector-tensor (VT) theory of gravitation was tested in previous papers. In the background universe, the vector field of the theory has a certain energy density, which is appropriate to play the role of vacuum energy (cosmological constant). ... More
Unsupervised learning from videos using temporal coherency deep networksJan 24 2018Oct 11 2018In this work we address the challenging problem of unsupervised learning from videos. Existing methods utilize the spatio-temporal continuity in contiguous video frames as regularization for the learning process. Typically, this temporal coherence of ... More
ISA$^2$: Intelligent Speed Adaptation from AppearanceOct 11 2018In this work we introduce a new problem named Intelligent Speed Adaptation from Appearance (ISA$^2$). Technically, the goal of an ISA$^2$ model is to predict for a given image of a driving scenario the proper speed of the vehicle. Note this problem is ... More
Hot Dust Obscured Galaxies with Excess Blue Light: Dual AGN or Single AGN Under Extreme Conditions?Nov 16 2015Feb 01 2016Hot Dust-Obscured Galaxies (Hot DOGs) are a population of hyper-luminous infrared galaxies identified by the WISE mission from their very red mid-IR colors, and characterized by hot dust temperatures ($T>60~\rm K$). Several studies have shown clear evidence ... More
Mid-Infrared Galaxy Luminosity Functions from the AGN and Galaxy Evolution SurveyFeb 17 2009We present galaxy luminosity functions at 3.6, 4.5, 5.8, and 8.0 micron measured by combining photometry from the IRAC Shallow Survey with redshifts from the AGN and Galaxy Evolution Survey of the NOAO Deep Wide-Field Survey Bootes field. The well-defined ... More
Low Resolution Spectral Templates For AGNs and Galaxies From 0.03 -- 30 micronsSep 21 2009Mar 09 2010We present a set of low resolution empirical SED templates for AGNs and galaxies in the wavelength range from 0.03 to 30 microns based on the multi-wavelength photometric observations of the NOAO Deep-Wide Field Survey Bootes field and the spectroscopic ... More
The Multiple Merger Assembly of a Hyper-luminous Obscured Quasar at redshift 4.6Nov 14 2018Galaxy mergers and gas accretion from the cosmic web drove the growth of galaxies and their central black holes at early epochs. We report spectroscopic imaging of a multiple merger event in the most luminous known galaxy, WISE J224607.56-052634.9 (W2246-0526), ... More
The Most Luminous Galaxies Discovered by WISEOct 07 2014Apr 08 2015We present 20 WISE-selected galaxies with bolometric luminosities L_bol > 10^14 L_sun, including five with infrared luminosities L_IR = L(rest 8-1000 micron) > 10^14 L_sun. These "extremely luminous infrared galaxies," or ELIRGs, were discovered using ... More
Characterizing the Mid-IR Extragalactic Sky with WISE and SDSSSep 10 2012Dec 19 2012The Wide-field Infrared Survey Explorer (WISE) has completed its all-sky survey at 3.4-22 micron. We merge the WISE data with optical SDSS data and provide a phenomenological characterization of mid-IR, extragalactic sources. WISE is most sensitive at ... More
The circumstellar medium of the peculiar supernova SN1997abSep 16 1998We report the detection of the slow moving wind into which the compact supernova remnant SN 1997ab is expanding. Echelle spectroscopy provides clear evidence for a well resolved narrow (Full Width at Zero Intensity, FWZI ~ 180 km/s) P-Cygni profile, both ... More
The hosts of $z=2$ QSOsFeb 07 1997We present results of the hosts of four high-redshift ($z \approx 2$) and high luminosity ($M_B \lsim -28$ mag) QSOs, three radio-quiet one radio-loud, imaged in R and K bands. The extensions to the nuclear unresolved source are most likely due to the ... More
Presence of Two Maxima in the Isothermal Free-Radical Polymerization Rate of Isobornyl Methacrylate Retarded by OxygenNov 21 2013Nov 26 2013The kinetics of the free-radical polymerization of isobornyl methacrylate (IBoMA) at 80C, initiated by benzoyl peroxide (BPO), was determined by differential scanning calorimetry (DSC), using sample pans previously sealed in air or in nitrogen. The polymerization ... More
Kinetics of the Free-Radical Polymerization of Isobornyl Methacrylate in the Presence of Polyisobutylenes of Different Molar MassesNov 21 2013The effect of a linear polymer dissolved in a reactive monomer on the kinetics of free-radical polymerization is studied. The selected system was a solution of polyisobutylene (PIB) in isobornyl methacrylate (IBoMA). Ternary phase diagrams of PIB, IBoMA ... More
Thermodynamic Analysis of a Polymerization-Induced Phase Separation in Nanoparticle-Monomer-Polymer BlendsNov 21 2013We perform a thermodynamic analysis of the polymerization-induced phase separation in nanoparticle-monomer-polymer blends using a simple model recently proposed by V. V. Ginzburg (Macromolecules 2005, 38, 2362.). The model was adapted for ternary blends ... More
Representation Learning for Visual-Relational Knowledge GraphsSep 07 2017Mar 31 2018A visual-relational knowledge graph (KG) is a multi-relational graph whose entities are associated with images. We introduce ImageGraph, a KG with 1,330 relation types, 14,870 entities, and 829,931 images. Visual-relational KGs lead to novel probabilistic ... More
Answering Visual-Relational Queries in Web-Extracted Knowledge GraphsSep 07 2017May 03 2019A visual-relational knowledge graph (KG) is a multi-relational graph whose entities are associated with images. We explore novel machine learning approaches for answering visual-relational queries in web-extracted knowledge graphs. To this end, we have ... More
Interaction patterns of brain activity across space, time and frequency. Part I: methodsMar 15 2011Mar 16 2011We consider exploratory methods for the discovery of cortical functional connectivity. Typically, data for the i-th subject (i=1...NS) is represented as an NVxNT matrix Xi, corresponding to brain activity sampled at NT moments in time from NV cortical ... More
Black Rings in (Anti)-deSitter spaceJun 12 2008Jan 06 2009We construct solutions for thin black rings in Anti-deSitter and deSitter spacetimes using approximate methods. Black rings in AdS exist with arbitrarily large radius and satisfy a bound |J| \leq LM, which they saturate as their radius becomes infinitely ... More
Kinematic Modelling of Disc Galaxies using Graphics Processing UnitsOct 07 2015Dec 20 2015With large-scale Integral Field Spectroscopy (IFS) surveys of thousands of galaxies currently under-way or planned, the astronomical community is in need of methods, techniques and tools that will allow the analysis of huge amounts of data. We focus on ... More
The health of SUSY after the Higgs discovery and the XENON100 dataDec 19 2012Jul 30 2013We analyze the implications for the status and prospects of supersymmetry of the Higgs discovery and the last XENON data. We focus mainly, but not only, on the CMSSM and NUHM models. Using a Bayesian approach we determine the distribution of probability ... More
Spin Glass Behavior in the Dy3-xYxTaO7 SystemMay 21 2014Several x-compositions of the polycrystalline Dy3-xYxTaO7 system, crystallizing in the weberite-type structure, were synthesized and structurally characterized using Rietveld refinements based on X-ray diffraction data. In previous magnetic characterization ... More
Non-strongly isospectral spherical space formsMay 11 2015In this paper we describe recent results on explicit construction of lens spaces that are not strongly isospectral, yet they are isospectral on $p$-forms for every $p$. Such examples cannot be obtained by the Sunada method. We also discuss related results, ... More
Spectra of lens spaces from 1-norm spectra of congruence latticesNov 27 2013May 07 2015To every $n$-dimensional lens space $L$, we associate a congruence lattice $\mathcal L$ in $\mathbb Z^m$, with $n=2m-1$ and we prove a formula relating the multiplicities of Hodge-Laplace eigenvalues on $L$ with the number of lattice elements of a given ... More
Competing Styles of Statistical Mechanics: II. Comparison of Theory and Experiment and Further IllustrationsJun 10 2003Jan 12 2004In the present follow-up article of a previous one [1] we illustrate the use of the Unconventional Statistical Mechanics described and discussed in the latter. This is done via the analysis, resorting to Renyi approach, of experimental results in the ... More
Semi-analytical model of the contact resistance in two-dimensional semiconductorsJan 26 2017Contact resistance is a severe performance bottleneck for electronic devices based on two-dimensional layered (2D) semiconductors, whose contacts are Schottky rather than Ohmic. Although there is general consensus that the injection mechanism changes ... More
Learning Short-Cut Connections for Object CountingMay 08 2018Nov 15 2018Object counting is an important task in computer vision due to its growing demand in applications such as traffic monitoring or surveillance. In this paper, we consider object counting as a learning problem of a joint feature extraction and pixel-wise ... More
The State of the Solar Wind, Magnetosphere, and Ionosphere During the Maunder MinimumMar 19 2018Both direct observations and reconstructions from various datasets, suggest that conditions were radically different during the Maunder Minimum (MM) than during the space era. Using an MHD model, we develop a set of feasible solutions to infer the properties ... More