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Sample records for standard agn unified

  1. Toward a Unified AGN Structure

    Science.gov (United States)

    Kazanas, Demosthenes; Fukumura, Keigo; Shrader, Chris; Behar, Ehud; Contopoulosa, Ioannis

    2012-01-01

    We present a unified model for the structure and appearance of accretion powered sources across their entire luminosity range from galactic X-ray binaries (XRB) to luminous quasars, with emphasis on AG N and their phenomenology. Central to this model is the notion of MHD winds launched by the accretion disks that power these objects. These winds provide the matter that manifests as blueshifted absorption features in the UV and X-ray spectra of a large fraction of these sources; furthermore, their density distribution in the poloidal plane determines their "appearance" (i.e. the column and velocity structure of these absorption features and the obscuration of the continuum source) as a function of the observer inclination angle (a feature to which INTEGRAL has made significant contributions). This work focuses on just the broadest characteristics of these objects; nonetheless, it provides scaling laws that allow one to reproduce within this model the properties of objects extending in luminosity from luminous quasars to XRBs. Our general conclusion is that the AGN phenomenology can be accounted for in terms of three parameters: The wind maSS flux in units of the Eddington value, m(dot), the observers' inclination angle Theta and the logarithmic slope between the 0/UV and X-ray fluxes alpha(sub ox); however because of a correlation between alpha(sub ox) and UV luminosity the number of significant parameters is two. The AGN correlations implied by this model appear to extend to and consistent with the XRB phenomenology, suggesting the presence of a truly unified underlying structure for accretion powered sources.

  2. Discovery of 21 New Changing-look AGNs: Study on Evolution of AGNs and AGN Host Galaxies

    Science.gov (United States)

    Yang, Qian; Wu, Xuebing; Fan, Xiaohui; Jiang, Linhua; McGreer, Ian; Shangguan, Jinyi; Yao, Su; Wang, Bingquan; Joshi, Ravi; Green, Richard F.; Wang, Feige; Feng, Xiaotong; Fu, Yuming; Yang, Jinyi; Liu, Yuanqi

    2018-01-01

    The rare case of changing-look (CL) AGNs, with the appearance or disappearance of broad Balmer emission lines within a few years, challenges our understanding of the AGN unified model. We present a sample of 21 new CL AGNs at 0.08 Survey Explorer (WISE), were detected in 15 CL AGNs during the transition. The optical and mid-infrared variability is not consistent with the scenario of variable obscuration in 10 CL AGNs at higher than 3σ confidence level. We confirm a bluer-when-brighter trend in the optical. However, the mid-infrared colors W1‑W2 become redder when the objects become brighter in the W1 band, possibly due to a stronger hot dust contribution in the W2 band when the AGN activity becomes stronger. The physical mechanism of type transition is important for understanding the evolution of AGNs. The rare CL AGNs provide exceptional cases for the black hole and host stellar velocity dispersion relation studies at higher redshift. The faint state spectrum can be used to obtain the host stellar velocity dispersion without contamination from AGN component, and the bright state spectrum can be used to calculate the black hole mass with broad Balmer emission lines. The images at the non-AGN phase of CL AGNs are useful for studies of AGN host galaxies avoiding contamination from the luminous central engines.

  3. Concept of Draft International Standard for a Unified Approach to Space Program Quality Assurance

    Science.gov (United States)

    Stryzhak, Y.; Vasilina, V.; Kurbatov, V.

    2002-01-01

    For want of the unified approach to guaranteed space project and product quality assurance, implementation of many international space programs has become a challenge. Globalization of aerospace industry and participation of various international ventures with diverse quality assurance requirements in big international space programs requires for urgent generation of unified international standards related to this field. To ensure successful fulfillment of space missions, aerospace companies should design and process reliable and safe products with properties complying or bettering User's (or Customer's) requirements. Quality of the products designed or processed by subcontractors (or other suppliers) should also be in compliance with the main user (customer)'s requirements. Implementation of this involved set of unified requirements will be made possible by creating and approving a system (series) of international standards under a generic title Space Product Quality Assurance based on a system consensus principle. Conceptual features of the baseline standard in this system (series) should comprise: - Procedures for ISO 9000, CEN and ECSS requirements adaptation and introduction into space product creation, design, manufacture, testing and operation; - Procedures for quality assurance at initial (design) phases of space programs, with a decision on the end product made based on the principle of independence; - Procedures to arrange incoming inspection of products delivered by subcontractors (including testing, audit of supplier's procedures, review of supplier's documentation), and space product certification; - Procedures to identify materials and primary products applied; - Procedures for quality system audit at the component part, primary product and materials supplier facilities; - Unified procedures to form a list of basic performances to be under configuration management; - Unified procedures to form a list of critical space product components, and unified

  4. Unified programs nationally? Strengths and weaknesses of the learning standards

    Directory of Open Access Journals (Sweden)

    Ignacio Polo Martínez

    2014-06-01

    Full Text Available The inclusion of measurable learning standards as an element of the curriculum has definitely opened the door to the connection between the curriculum and external assessments. Since its origin, the potential impact of that element in improving our educational system has been defended and criticized. The truth is that in our country, though all regions are based on the same Royal Decree of core curriculum, and therefore the same reference for the evaluation, curriculum that ultimately applies to students ( teaching-learning- assessment from the different regions can have significant differences . This article proposes, from the analysis of various research , training programs, the plan of action for inspection and the author's own experience in processes of curriculum specifications , assess the potential strengths and weaknesses of the learning standards.

  5. Chinese green product standards: international experience and pathway for a unified system

    Science.gov (United States)

    Yun, Fu; Ling, Lin; Dongfeng, Gao; Shuo, Yang

    2017-11-01

    The establishment of a unified green product standard system is of great importance regarding the effective supply of green products and meeting trend of the consumption upgrade. It also is helpful to reduce the cost of green information disclosure of enterprises, and facilitate the supply-side structural reform. Based on the experience of developing and implementing green product standards in the EU, Germany, America, Japan and so on, combined with current Chinese standard systems including environmental protection, energy conservation, water conservation, low carbon, recycling, regeneration and organic, with the adoption of the life cycle thinking, this paper brings forward basic requirements on organizations including pollutant emissions, establishment of management system, energy conservation and emission reduction technology and green supply chain management, and proposes indicator requirements on product including resource attributes, energy attributes, environmental attributes and quality attributes, so as to guide the establishment of green product evaluation standards in the context of China.

  6. [Transfer of the AGnES concept to the regular German health-care system: legal evaluation, reimbursement, qualification].

    Science.gov (United States)

    van den Berg, N; Kleinke, S; Heymann, R; Oppermann, R F; Jakobi, B; Hoffmann, W

    2010-05-01

    According to an amendment of German social security legislation, the AGnES concept of delegation of certain tasks of medical care, especially house calls, by general practitioners (GPs) to qualified practice employees (AGnES employees), will be transferred into the regular German health care system from January 2009 onward. The concept was developed to support GPs in regions with imminent gaps in primary care. Patient data, the specifically delegated and all other activities carried out by the AGnES employees in the AGnES projects were digitally documented. Additionally, the participating GPs, AGnES employees and patients underwent a set of standardised interviews. A curriculum to qualify the AGnES employees and to define the requirements needed was developed. A legal assessment of all delegated activities was carried out, and an economical model to calculate the necessary allowance was calculated. In seven model projects in four federal states in Germany, 11,228 house calls were carried out involving 1,424, mostly multimorbid, patients (mean age: 78.6 years). A modular structured curriculum, considering the basic education and acquired competences, was developed. It allows for an individual qualification of the AGnES employees. The result of the legal assessment was the central relevance of the qualification of the practice employees according to the AGnES curriculum as the essential condition for carrying out the entire range of activities of the AGnES concept. The economic model revealed euro 21.58 for a house call by an AGnES employee. The underlying model referred to underserved regions. A successful transfer of the AGnES concept with a high standard of quality into regular health-care depends on several factors. Of particular importance is the specific qualification of the practice employees, which is a central legal condition for the delegation of medical tasks from GPs to AGnEs employees. A second determining factor is also an adequate reimbursement within

  7. COST meeting - Polarization and AGN II - Abstracts and slides

    International Nuclear Information System (INIS)

    Kishimoto, M.; Rouan, D.; Tadhunter, C.; Lopez Rodriguez, E.; Braibant, L.; Pasetto, A.; Matt, G.; Afanasiev, V.; Lira, P.; Hutsemekers, D.; Sluse, D.; Marin, F.; Tamborra, F.; Yankova, K.; Laing, R.; Lico, R.; Agudo, I.; Hovatta, T.; Jermak, H.; Chen, X.; Myserlis, I.; Cellone, S.A.; Chidiac, C.; Chakraborty, N.; Bozhilov, V.

    2016-01-01

    This meeting is the 2. COST workshop on Polarization and Active Galactic Nuclei (AGN). Accreting supermassive black holes in active galactic nuclei are the most powerful, long-lasting sources in the universe. Emitting over ten orders of magnitude in photon energy or more, the radiation of AGN encodes information about a multitude of astrophysical processes: accretion, thermal and non-thermal radiative transfer, acceleration of outflows and jets, shock physics, special and general relativity. Observationally, AGN appear as numerous types and polarization studies have played a key role in establishing the idea of a unifying AGN geometry. The topics covered at the meeting include the following: 1) Polarimetry of AGN from the radio to gamma-rays; 2) Tools for modeling and data analysis of AGN polarization; 3) Polarization due to magnetic fields and dust in AGN; 4) Polarization of AGN inflows, outflows and jets; 5) Spectropolarimetry and polarization variability of AGN; and 6) From Sgr A* to the most luminous quasars: what can polarimetry do for AGN (super-)unification? This document is made up of the abstracts and slides of the presentations

  8. General analysis of corrections to the standard seesaw formula in grand unified models

    International Nuclear Information System (INIS)

    Barr, S.M.; Kyae, Bumseok

    2004-01-01

    In realistic grand unified models there are typically extra vectorlike matter multiplets at the GUT-scale that are needed to explain the family hierarchy. These contain neutrinos that, when integrated out, can modify the usual neutrino seesaw formula. A general analysis is given. It is noted that such modifications can explain why the neutrinos do not exhibit a strong family hierarchy like the other types of fermions

  9. Standard representation and unified stability analysis for dynamic artificial neural network models.

    Science.gov (United States)

    Kim, Kwang-Ki K; Patrón, Ernesto Ríos; Braatz, Richard D

    2018-02-01

    An overview is provided of dynamic artificial neural network models (DANNs) for nonlinear dynamical system identification and control problems, and convex stability conditions are proposed that are less conservative than past results. The three most popular classes of dynamic artificial neural network models are described, with their mathematical representations and architectures followed by transformations based on their block diagrams that are convenient for stability and performance analyses. Classes of nonlinear dynamical systems that are universally approximated by such models are characterized, which include rigorous upper bounds on the approximation errors. A unified framework and linear matrix inequality-based stability conditions are described for different classes of dynamic artificial neural network models that take additional information into account such as local slope restrictions and whether the nonlinearities within the DANNs are odd. A theoretical example shows reduced conservatism obtained by the conditions. Copyright © 2017. Published by Elsevier Ltd.

  10. GLAST and AGN Science

    Science.gov (United States)

    Reyes, Luis C.

    2006-04-01

    The Large Area Telescope (LAT) on board GLAST (Gamma-ray Large Area Space Telescope) is an instrument under construction to study the gamma-ray sky in the energy range 20 MeV to >300 GeV with special interest in the previously unexplored region between a few GeV and a few hundred GeV. Among the high energy gamma-ray sources in the sky, the Blazar-class of AGNs are distinguished because of their brightness and very short term variability. GLAST's improved sensitivity with respect to previous missions will increase the number of known AGN gamma-ray sources from about 100 to thousands, with redshifts up to z>4. Science returns with GLAST include: examination of the blazar sequence model, test of leptonic and hadronic models for particle acceleration, physics of relativistic jets, and evolution of Blazar AGNs population with cosmic time. Special consideration will be given to the possibility of using the large size of the GLAST Blazar catalog to distinguish intrinsic spectra of AGNs from the redshift dependent effects of attenuation by the Extragalactic Background Light (EBL). A measured attenuation as a function of AGN redshift would constitute and effective and unique probe to the optical-UV EBL.

  11. From plastic to gold: a unified classification scheme for reference standards in medical image processing

    Science.gov (United States)

    Lehmann, Thomas M.

    2002-05-01

    Reliable evaluation of medical image processing is of major importance for routine applications. Nonetheless, evaluation is often omitted or methodically defective when novel approaches or algorithms are introduced. Adopted from medical diagnosis, we define the following criteria to classify reference standards: 1. Reliance, if the generation or capturing of test images for evaluation follows an exactly determined and reproducible protocol. 2. Equivalence, if the image material or relationships considered within an algorithmic reference standard equal real-life data with respect to structure, noise, or other parameters of importance. 3. Independence, if any reference standard relies on a different procedure than that to be evaluated, or on other images or image modalities than that used routinely. This criterion bans the simultaneous use of one image for both, training and test phase. 4. Relevance, if the algorithm to be evaluated is self-reproducible. If random parameters or optimization strategies are applied, reliability of the algorithm must be shown before the reference standard is applied for evaluation. 5. Significance, if the number of reference standard images that are used for evaluation is sufficient large to enable statistically founded analysis. We demand that a true gold standard must satisfy the Criteria 1 to 3. Any standard only satisfying two criteria, i.e., Criterion 1 and Criterion 2 or Criterion 1 and Criterion 3, is referred to as silver standard. Other standards are termed to be from plastic. Before exhaustive evaluation based on gold or silver standards is performed, its relevance must be shown (Criterion 4) and sufficient tests must be carried out to found statistical analysis (Criterion 5). In this paper, examples are given for each class of reference standards.

  12. Host Galaxy Properties of the Swift BAT Ultra Hard X-Ray Selected AGN

    Science.gov (United States)

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa M.; Baumgartner, Wayne; Tueller, Jack; Gehrels, Neil; Valencic, Lynne

    2011-01-01

    We have assembled the largest sample of ultra hard X-ray selected (14-195 keV) AGN with host galaxy optical data to date, with 185 nearby (zBAT) sample. The BAT AGN host galaxies have intermediate optical colors (u -- r and g -- r) that are bluer than a comparison sample of inactive galaxies and optically selected AGN from the Sloan Digital Sky Survey (SDSS) which are chosen to have the same stellar mass. Based on morphological classifications from the RC3 and the Galaxy Zoo, the bluer colors of BAT AGN are mainly due to a higher fraction of mergers and massive spirals than in the comparison samples. BAT AGN in massive galaxies (log Stellar Mass >10.5) have a 5 to 10 times higher rate of spiral morphologies than in SDSS AGN or inactive galaxies. We also see enhanced far-IR emission in BAT AGN suggestive of higher levels of star formation compared to the comparison samples. BAT AGN are preferentially found in the most massive host galaxies with high concentration indexes indicative of large bulge-to-disk ratios and large supermassive black holes. The narrow-line (NL) BAT AGN have similar intrinsic luminosities as the SDSS NL Seyferts based on measurements of [O III] Lambda 5007. There is also a correlation between the stellar mass and X-ray emission. The BAT AGN in mergers have bluer colors and greater ultra hard X-ray emission compared to the BAT sample as whole. In agreement with the Unified Model of AGN, and the relatively unbiased nature of the BAT sources, the host galaxy colors and morphologies are independent of measures of obscuration such as X-ray column density or Seyfert type. The high fraction of massive spiral galaxies and galaxy mergers in BAT AGN suggest that host galaxy morphology is related to the activation and fueling of local AGN.

  13. AGN Science with AGIS

    Science.gov (United States)

    Coppi, Paolo

    2009-05-01

    AGIS, a proposed future gamma-ray telescope consisting of a square km array of 50 atmospheric Cherenkov telescopes, will provide a powerful new view of the high energy universe. The combination of its increased sensitivity (a factor 10 over current observatories), increased survey capabilities, and a low energy threshold (<30 GeV) that allows observations at energies not subject to absorption on extragalactic background light will result in a dramatic increase in the number of AGN accessible at high energies. The overall number of ``TeV blazar" AGN, those detected by current ground-based observatories, should increase by a factor 30 or more with a corresponding increase in the number of these that can be monitored at high statistical significance to test emission models rigorously. More excitingly, AGIS may also begin to pick up entirely new classes of AGN such as radio galaxies with X-ray emitting hotspots at large distances from the central engine, providing further insight into the outflows from AGN. The low AGIS threshold energy will also allow significant source overlap with objects detected by the recently launched Fermi gamma-ray space observatory at lower, GeV energies. AGIS will significantly improve on the localization and variability monitoring of the Fermi sources it sees.

  14. Unified communications

    OpenAIRE

    Kravos, Urban

    2011-01-01

    In the modern business world, communication are becoming more and more complex. As a solution to this problem unified communications occurred. Using a single communication approach unified communications are the integration of various communication technologies (eg, telephony, unified messaging, audio, video and web conferencing and collaboration tools). Unified Messaging, which represents only part of the unified communications means the integration of different non real time communication t...

  15. Unified communication and standardized data exchange for underground mines; Einheitliche, standardisierte Kommunikation zur Effizienzsteigerung von Bergwerken

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, C. [Embigence GmbH, Ladbergen (Germany)

    2006-11-07

    Communication in many forms during the past ten years has changed our daily life: Cellphone technology as well as the Internet are just two examples. In the same way, modern network based communication now starts to change the way how underground mines are run: The lack of proper communication traditionally caused downtime and production loss. In the future, mine communication will be crucial for efficiency and profitability of underground operations. This enables intelligent machines to be used like e.g. a machine server equipped drill rig at LKAB or highly advanced, networked monorail systems at DSK. Standardized communication and information exchange is a basis for using three dimensional visualization tools to support decision finding. The paper explains these visions and goals for the future and explains the feasibility by two running example applications. (orig.)

  16. Beyond Mathematics, a Standard Elementary Particle, and the Unified Field of Energy

    International Nuclear Information System (INIS)

    Sourial, A.S.

    2008-01-01

    Teaching methods are presented based on a theoretical logical thesis of: A Standard Elementary Particle, i nstead of the current 200 odd different subatomic particles, and their plausible derivation from such a standard particle, similar to the derivation of our body cells from a multi potential S tem Cell, T he thesis reintroduces the theory of A Material Ether a s a necessary medium for the transmission of the Electro-Magnetic-Gravitational Waves. It solves and demystifies the following riddles: 1. The A ether Vacuum, by offering a plausible composition of A n elastic solid medium, t hat meets the specific physical requirements needed for the transmission of the electro magnetic gravitational waves, Explains the vast amount of Potential Energy that such an A ether can carry, That there is No Action at a Distance, 2. It explains Q uantum Mechanics, o n simple Newtonian principles, It nullifies the H eisenberg Uncertainty Principle, s howing that there is no uncertainty whatsoever, for individual particle interactions, and the existence of F unctional Barriers f or the disc like aggregates of contiguous particles representing I ntra-atomic Electrons, a nd A full P hysical e xplanation of the their quantum numbers, their electronic shells, as well as: The Pauli Exclusion Principle. 3. The possible explanation of Hubbell's Law without an expansion of the Universe, that the C osmic Red Shift g ives the illusion of an expanding Universe similar to that of the B ent Stick i n the water due to refraction. 4. That the Big Bang I nflation Theory, f or the origin of the Universe is: a Figment of Imagination similar to Aladdin's D jinni out of the bottle. a nd a Fantasy of Mathematics with complete lack of touch with reality. The thesis suggests a plausible explanation - Modus Operandi - for, and composition of: i) Gravity, II) The structure of nucleons, III) The nature of the strong force, IV) The structure of the string of The String Theory

  17. Continuum Reverberation Mapping of AGN Accretion Disks

    Energy Technology Data Exchange (ETDEWEB)

    Fausnaugh, Michael M. [Department of Astronomy, Ohio State University, Columbus, OH (United States); MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA (United States); Peterson, Bradley M. [Department of Astronomy, Ohio State University, Columbus, OH (United States); Center for Cosmology and AstroParticle Physics, Ohio State University, Columbus, OH (United States); Space Telescope Science Institute, Baltimore, MD (United States); Starkey, David A. [SUPA Physics and Astronomy, University of St. Andrews, Scotland (United Kingdom); Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL (United States); Horne, Keith, E-mail: faus@mit.edu [SUPA Physics and Astronomy, University of St. Andrews, Scotland (United Kingdom); Collaboration: the AGN STORM Collaboration

    2017-12-05

    We show recent detections of inter-band continuum lags in three AGN (NGC 5548, NGC 2617, and MCG+08-11-011), which provide new constraints on the temperature profiles and absolute sizes of the accretion disks. We find lags larger than would be predicted for standard geometrically thin, optically thick accretion disks by factors of 2.3–3.3. For NGC 5548, the data span UV through optical/near-IR wavelengths, and we are able to discern a steeper temperature profile than the T ~ R{sup −3/4} expected for a standard thin disk. Using a physical model, we are also able to estimate the inclinations of the disks for two objects. These results are similar to those found from gravitational microlensing of strongly lensed quasars, and provide a complementary approach for investigating the accretion disk structure in local, low luminosity AGN.

  18. Modeling optical and UV polarization of AGNs. IV. Polarization timing

    Science.gov (United States)

    Rojas Lobos, P. A.; Goosmann, R. W.; Marin, F.; Savić, D.

    2018-03-01

    Context. Optical observations cannot resolve the structure of active galactic nuclei (AGN), and a unified model for AGN was inferred mostly from indirect methods, such as spectroscopy and variability studies. Optical reverberation mapping allowed us to constrain the spatial dimension of the broad emission line region and thereby to measure the mass of supermassive black holes. Recently, reverberation was also applied to the polarized signal emerging from different AGN components. In principle, this should allow us to measure the spatial dimensions of the sub-parsec reprocessing media. Aim. We conduct numerical modeling of polarization reverberation and provide theoretical predictions for the polarization time lag induced by different AGN components. The model parameters are adjusted to the observational appearance of the Seyfert 1 galaxy NGC 4151. Methods: We modeled scattering-induced polarization and tested different geometries for the circumnuclear dust component. Our tests included the effects of clumpiness and different dust prescriptions. To further extend the model, we also explored the effects of additional ionized winds stretched along the polar direction, and of an equatorial scattering ring that is responsible for the polarization angle observed in pole-on AGN. The simulations were run using a time-dependent version of the STOKES code. Results: Our modeling confirms the previously found polarization characteristics as a function of the observer`s viewing angle. When the dust adopts a flared-disk geometry, the lags reveal a clear difference between type 1 and type 2 AGN. This distinction is less clear for a torus geometry where the time lag is more sensitive to the geometry and optical depth of the inner surface layers of the funnel. The presence of a scattering equatorial ring and ionized outflows increased the recorded polarization time lags, and the polar outflows smooths out dependence on viewing angle, especially for the higher optical depth of the

  19. [Assessment of the relationship of properties of chemical compounds and their toxicity to a unified hygienic standardization for chemicals].

    Science.gov (United States)

    Trushkov, V F; Perminov, K A; Sapozhnikova, V V; Ignatova, O L

    2013-01-01

    The connection of thermodynamic properties and parameters of toxicity of chemical substances was determined. Obtained data are used for the evaluation of toxicity and hygienic rate setting of chemical compounds. The relationship between enthalpy and toxicity of chemical compounds has been established. Orthogonal planning of the experiment was carried out in the course of the investigations. Equation of unified hygienic rate setting in combined, complex, conjunct influence on the organism is presented. Prospects of determination of toxicity and methodology of unified hygienic rate setting in combined, complex, conjunct influence on the organism are presented

  20. ISOTROPIC LUMINOSITY INDICATORS IN A COMPLETE AGN SAMPLE

    International Nuclear Information System (INIS)

    Diamond-Stanic, Aleksandar M.; Rieke, George H.; Rigby, Jane R.

    2009-01-01

    The [O IV] λ25.89 μm line has been shown to be an accurate indicator of active galactic nucleus (AGN) intrinsic luminosity in that it correlates well with hard (10-200 keV) X-ray emission. We present measurements of [O IV] for 89 Seyfert galaxies from the unbiased revised Shapley-Ames (RSA) sample. The [O IV] luminosity distributions of obscured and unobscured Seyferts are indistinguishable, indicating that their intrinsic AGN luminosities are quite similar and that the RSA sample is well suited for tests of the unified model. In addition, we analyze several commonly used proxies for AGN luminosity, including [O III] λ5007 A, 6 cm radio, and 2-10 keV X-ray emission. We find that the radio luminosity distributions of obscured and unobscured AGNs show no significant difference, indicating that radio luminosity is a useful isotropic luminosity indicator. However, the observed [O III] and 2-10 keV luminosities are systematically smaller for obscured Seyferts, indicating that they are not emitted isotropically.

  1. AGN feedback in galaxy formation

    CERN Document Server

    Antonuccio-Delogu, Vincenzo

    2010-01-01

    During the past decade, convincing evidence has been accumulated concerning the effect of active galactic nuclei (AGN) activity on the internal and external environment of their host galaxies. Featuring contributions from well-respected researchers in the field, and bringing together work by specialists in both galaxy formation and AGN, this volume addresses a number of key questions about AGN feedback in the context of galaxy formation. The topics covered include downsizing and star-formation time scales in massive elliptical galaxies, the connection between the epochs of supermassive black h

  2. Fueling the AGN

    Science.gov (United States)

    Combes, F.

    Active Galactic Nuclei are fueled from material (gas or stars) that are in general far away from the gravitational influence of the central black hole, the engine thought to be responsible for their activity. The required material has a lot of angular momentum that, a priori, is quite difficult to evacuate. The various dynamical mechanisms that may play a role in this game are reviewed, including m = 2 perturbations (bars and spirals), m = 1 perturbations (spirals, warps, lopsidedness), and tidal interactions between galaxies and mergers. In the latest stages of the merger, a binary black hole could be formed, and its influence on the dynamics and fueling is discussed. Starbursts are often associated with AGN, and the nature of their particular connection, and their role in the nuclear fueling is described. Evolution of the fueling efficiency with redshift is addressed.

  3. AGES: THE AGN AND GALAXY EVOLUTION SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Kochanek, C. S. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Eisenstein, D. J.; Caldwell, N.; Jones, C.; Murray, S. S.; Forman, W. R.; Green, P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Cool, R. J. [Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544 (United States); Assef, R. J.; Eisenhardt, P.; Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Jannuzi, B. T.; Dey, A. [NOAO, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Brown, M. J. I. [School of Physics, Monash University, Clayton, Victoria 3800 (Australia); Gonzalez, A. H. [Department of Astronomy, Bryant Space Science Center, University of Florida, Gainesville, FL 32611 (United States)

    2012-05-01

    The AGN and Galaxy Evolution Survey (AGES) is a redshift survey covering, in its standard fields, 7.7 deg{sup 2} of the Booetes field of the NOAO Deep Wide-Field Survey. The final sample consists of 23,745 redshifts. There are well-defined galaxy samples in 10 bands (the B{sub W} , R, I, J, K, IRAC 3.6, 4.5, 5.8, and 8.0 {mu}m, and MIPS 24 {mu}m bands) to a limiting magnitude of I < 20 mag for spectroscopy. For these galaxies, we obtained 18,163 redshifts from a sample of 35,200 galaxies, where random sparse sampling was used to define statistically complete sub-samples in all 10 photometric bands. The median galaxy redshift is 0.31, and 90% of the redshifts are in the range 0.085 < z < 0.66. Active galactic nuclei (AGNs) were selected as radio, X-ray, IRAC mid-IR, and MIPS 24 {mu}m sources to fainter limiting magnitudes (I < 22.5 mag for point sources). Redshifts were obtained for 4764 quasars and galaxies with AGN signatures, with 2926, 1718, 605, 119, and 13 above redshifts of 0.5, 1, 2, 3, and 4, respectively. We detail all the AGES selection procedures and present the complete spectroscopic redshift catalogs and spectral energy distribution decompositions. Photometric redshift estimates are provided for all sources in the AGES samples.

  4. Fading AGN Candidates: AGN Histories and Outflow Signatures

    Energy Technology Data Exchange (ETDEWEB)

    Keel, William C.; Maksym, W. Peter [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487 (United States); Lintott, Chris J. [Astrophysics, Oxford University and Adler Planetarium, 1300 S. Lakeshore Drive, Chicago, IL 60605 (United States); Bennert, Vardha N.; Scott, Bryan; Showley, Charles; Flatland, Kelsi [Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407 (United States); Chojnowski, S. Drew [Department of Astronomy, New Mexico State University, P.O. Box 30001, MSC 4500, Las Cruces, NM 88003-8001 (United States); Moiseev, Alexei; Smirnova, Aleksandrina [Special Astrophysical Observatory, Russian Academy of Sciences, Nizhny Arkhyz, 369167 (Russian Federation); Schawinski, Kevin; Sartori, Lia F. [Institute for Astronomy, ETH Zürich, Wolfgang-Pauli-Straße 27, CH-8093 Zurich (Switzerland); Urry, C. Megan [Department of Physics, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States); Pancoast, Anna [Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Schirmer, Mischa, E-mail: wkeel@ua.edu [Gemini Observatory, La Serena (Chile)

    2017-02-01

    We consider the energy budgets and radiative history of eight fading active galactic nuclei (AGNs), identified from an energy shortfall between the requirements to ionize very extended (radius > 10 kpc) ionized clouds and the luminosity of the nucleus as we view it directly. All show evidence of significant fading on timescales of ≈50,000 yr. We explore the use of minimum ionizing luminosity Q {sub ion} derived from photoionization balance in the brightest pixels in H α at each projected radius. Tests using presumably constant Palomar–Green QSOs, and one of our targets with detailed photoionization modeling, suggest that we can derive useful histories of individual AGNs, with the caveat that the minimum ionizing luminosity is always an underestimate and subject to uncertainties about fine structure in the ionized material. These consistency tests suggest that the degree of underestimation from the upper envelope of reconstructed Q {sub ion} values is roughly constant for a given object and therefore does not prevent such derivation. The AGNs in our sample show a range of behaviors, with rapid drops and standstills; the common feature is a rapid drop in the last ≈2×10{sup 4} yr before the direct view of the nucleus. The e -folding timescales for ionizing luminosity are mostly in the thousands of years, with a few episodes as short as 400 yr. In the limit of largely obscured AGNs, we find additional evidence for fading from the shortfall between even the lower limits from recombination balance and the maximum luminosities derived from far-infrared fluxes. We compare these long-term light curves, and the occurrence of these fading objects among all optically identified AGNs, to simulations of AGN accretion; the strongest variations over these timespans are seen in models with strong and local (parsec-scale) feedback. We present Gemini integral-field optical spectroscopy, which shows a very limited role for outflows in these ionized structures. While rings and

  5. Fading AGN Candidates: AGN Histories and Outflow Signatures

    International Nuclear Information System (INIS)

    Keel, William C.; Maksym, W. Peter; Lintott, Chris J.; Bennert, Vardha N.; Scott, Bryan; Showley, Charles; Flatland, Kelsi; Chojnowski, S. Drew; Moiseev, Alexei; Smirnova, Aleksandrina; Schawinski, Kevin; Sartori, Lia F.; Urry, C. Megan; Pancoast, Anna; Schirmer, Mischa

    2017-01-01

    We consider the energy budgets and radiative history of eight fading active galactic nuclei (AGNs), identified from an energy shortfall between the requirements to ionize very extended (radius > 10 kpc) ionized clouds and the luminosity of the nucleus as we view it directly. All show evidence of significant fading on timescales of ≈50,000 yr. We explore the use of minimum ionizing luminosity Q ion derived from photoionization balance in the brightest pixels in H α at each projected radius. Tests using presumably constant Palomar–Green QSOs, and one of our targets with detailed photoionization modeling, suggest that we can derive useful histories of individual AGNs, with the caveat that the minimum ionizing luminosity is always an underestimate and subject to uncertainties about fine structure in the ionized material. These consistency tests suggest that the degree of underestimation from the upper envelope of reconstructed Q ion values is roughly constant for a given object and therefore does not prevent such derivation. The AGNs in our sample show a range of behaviors, with rapid drops and standstills; the common feature is a rapid drop in the last ≈2×10 4 yr before the direct view of the nucleus. The e -folding timescales for ionizing luminosity are mostly in the thousands of years, with a few episodes as short as 400 yr. In the limit of largely obscured AGNs, we find additional evidence for fading from the shortfall between even the lower limits from recombination balance and the maximum luminosities derived from far-infrared fluxes. We compare these long-term light curves, and the occurrence of these fading objects among all optically identified AGNs, to simulations of AGN accretion; the strongest variations over these timespans are seen in models with strong and local (parsec-scale) feedback. We present Gemini integral-field optical spectroscopy, which shows a very limited role for outflows in these ionized structures. While rings and loops of emission

  6. AGN Clustering in the BAT Sample

    Science.gov (United States)

    Powell, Meredith; Cappelluti, Nico; Urry, Meg; Koss, Michael; BASS Team

    2018-01-01

    We characterize the environments of local growing supermassive black holes by measuring the clustering of AGN in the Swift-BAT Spectroscopic Survey (BASS). With 548 AGN in the redshift range 0.012MASS galaxies, we constrain the halo occupation distribution (HOD) of the full sample with unprecedented sensitivity, as well as in bins of obscuration with matched luminosity distributions. In doing so, we find that AGN tend to reside in galaxy groups, agreeing with previous studies of AGN throughout a large range of luminosity and redshift. We also find evidence that obscured AGN tend to reside in denser environments than unobscured AGN.

  7. Multi-phase outflows as probes of AGN accretion history

    Science.gov (United States)

    Nardini, Emanuele; Zubovas, Kastytis

    2018-05-01

    Powerful outflows with a broad range of properties (such as velocity, ionization, radial scale and mass loss rate) represent a key feature of active galactic nuclei (AGN), even more so since they have been simultaneously revealed also in individual objects. Here we revisit in a simple analytical framework the recent remarkable cases of two ultraluminous infrared quasars, IRAS F11119+3257 and Mrk 231, which allow us to investigate the physical connection between multi-phase AGN outflows across the ladder of distance from the central supermassive black hole (SMBH). We argue that any major deviations from the standard outflow propagation models might encode unique information on the past SMBH accretion history, and briefly discuss how this could help address some controversial aspects of the current picture of AGN feedback.

  8. Heavily Obscured AGN with SIMBOL-X

    International Nuclear Information System (INIS)

    Ceca, R. Della; Caccianiga, A.; Severgnini, P.

    2009-01-01

    By comparing an optically selected sample of narrow lines AGN with an X-ray selected sample of AGN we have recently derived an estimate of the intrinsic (i.e. before absorption) 2-10 keV luminosity function (XLF) of Compton Thick AGNs. We will use this XLF to derive the number of Compton Thick AGN that will be found in the SIMBOL-X survey(s).

  9. Heavily Obscured AGN with SIMBOL-X

    Science.gov (United States)

    Della Ceca, R.; Caccianiga, A.; Severgnini, P.

    2009-05-01

    By comparing an optically selected sample of narrow lines AGN with an X-ray selected sample of AGN we have recently derived an estimate of the intrinsic (i.e. before absorption) 2-10 keV luminosity function (XLF) of Compton Thick AGNs. We will use this XLF to derive the number of Compton Thick AGN that will be found in the SIMBOL-X survey(s).

  10. Unifying Abstractions

    DEFF Research Database (Denmark)

    Torgersen, Mads

    This thesis presents the RUNE language, a semantic construction of related and tightly coupled programming constructs presented in the shape of a programming language. The major contribution is the succesfull design of a highly unified and general programming model, capable of expressing some of ...... a unified name declaration mechanism. The resulting expressiveness allows for argument covariance, dependent types and module types, plus a solution to the so-called expression problem of two way extensibility in object-oriented languages....... of the most complex type relations put forth in type systems research, without compromising such fundamental qualities as conceptuality, modularity and static typing. While many new constructs and unifications are put forth  to substantiate their conceptual validity, type rules are given to support...

  11. Why unify

    International Nuclear Information System (INIS)

    Georgi, H.

    1980-01-01

    Unified gauge theories such as SU(5) of particle interactions are built on the colour SU(3) and SU(2) x U(1) gauge theories which apparently describe strong and weak and electromagnetic interactions at distances as small as 10 -16 cm. In this article the classical reasons for going beyond SU(3)xSU(2)xU(1) to a fully unified theory such as SU(5) are reviewed, and a new reason formulated. A class of imaginary worlds similar to our own is considered and it is shown that unification is possible only in ours. This suggests that the low-energy interactions are unique in that they are constructed to make unification possible. (author)

  12. Non-thermal AGN models

    Energy Technology Data Exchange (ETDEWEB)

    Band, D.L.

    1986-12-01

    The infrared, optical and x-ray continua from radio quiet active galactic nuclei (AGN) are explained by a compact non-thermal source surrounding a thermal ultraviolet emitter, presumably the accretion disk around a supermassive black hole. The ultraviolet source is observed as the ''big blue bump.'' The flat (..cap alpha.. approx. = .7) hard x-ray spectrum results from the scattering of thermal ultraviolet photons by the flat, low energy end of an electron distribution ''broken'' by Compton losses; the infrared through soft x-ray continuum is the synchrotron radiation of the steep, high energy end of the electron distribution. Quantitative fits to specific AGN result in models which satisfy the variability constraints but require electron (re)acceleration throughout the source. 11 refs., 1 fig.

  13. The BAT AGN Spectroscopic Survey (BASS)

    Science.gov (United States)

    Koss, Michael

    2017-08-01

    We present the Swift BAT AGN Spectroscopic Survey (BASS) and discus the first four papers. The catalog represents an unprecedented census of hard-X-ray selected AGN in the local universe, with ~90% of sources at zpast studies. Consistent with previous surveys, we find an increase in the fraction of un-obscured (type 1) AGN, as measured from broad Hbeta and Halpha, with increasing 14-195 keV and 2-10 keV luminosity. We find the FWHM of the emission lines to show broad agreement with the X-ray obscuration measurements. Compared to narrow line AGN in the SDSS, the X-ray selected AGN in our sample with emission lines have a larger fraction of dustier galaxies suggesting these types of galaxies are missed in optical AGN surveys using emission line diagnostics.

  14. Toward the standard population synthesis model of the X-ray background: Evolution of X-ray luminosity and absorption functions of active galactic nuclei including Compton-thick populations

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Yoshihiro [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Akiyama, Masayuki [Astronomical Institute, Tohoku University, 6-3 Aramaki, Aoba-ku, Sendai 980-8578 (Japan); Hasinger, Günther [Institute for Astronomy, 2680 Woodlawn Drive Honolulu, HI 96822-1839 (United States); Miyaji, Takamitsu [Instituto de Astronomía, Universidad Nacional Autónoma de México, Ensenada, Baja California (Mexico); Watson, Michael G. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)

    2014-05-10

    We present the most up to date X-ray luminosity function (XLF) and absorption function of active galactic nuclei (AGNs) over the redshift range from 0 to 5, utilizing the largest, highly complete sample ever available obtained from surveys performed with Swift/BAT, MAXI, ASCA, XMM-Newton, Chandra, and ROSAT. The combined sample, including that of the Subaru/XMM-Newton Deep Survey, consists of 4039 detections in the soft (0.5-2 keV) and/or hard (>2 keV) band. We utilize a maximum likelihood method to reproduce the count rate versus redshift distribution for each survey, by taking into account the evolution of the absorbed fraction, the contribution from Compton-thick (CTK) AGNs, and broadband spectra of AGNs, including reflection components from tori based on the luminosity- and redshift-dependent unified scheme. We find that the shape of the XLF at z ∼ 1-3 is significantly different from that in the local universe, for which the luminosity-dependent density evolution model gives much better description than the luminosity and density evolution model. These results establish the standard population synthesis model of the X-ray background (XRB), which well reproduces the source counts, the observed fractions of CTK AGNs, and the spectrum of the hard XRB. The number ratio of CTK AGNs to the absorbed Compton-thin (CTN) AGNs is constrained to be ≈0.5-1.6 to produce the 20-50 keV XRB intensity within present uncertainties, by assuming that they follow the same evolution as CTN AGNs. The growth history of supermassive black holes is discussed based on the new AGN bolometric luminosity function.

  15. Grand unified theories

    International Nuclear Information System (INIS)

    Langacker, P.

    1981-01-01

    In this talk I discuss the present status of these theories and of their observational and experimental implications. In section II, I briefly review the standard SU 3 sup(c) x SU 2 x U 1 model of the strong and electroweak interactions. Although phenomenologically successful, the standard model leaves many questions unanswered. Some of these questions are addressed by grand unified theories, which are defined and discussed in Section III. The Georgi-Glashow SU 5 model is described, as are theories based on larger groups such as SO 10 , E 6 , or SO 16 . It is emphasized that there are many possible grand unified theories and that it is an experimental problem not only to test the basic ideas but to discriminate between models. (orig./HSI)

  16. AGN feedback in action? - outflows and star formation in type 2 AGNs

    Science.gov (United States)

    Woo, Jong-Hak

    2017-01-01

    We present the statistical constraints on the ionized gas outflows and their connection to star formation, using a large sample of ~110,000 AGNs and star-forming galaxies at z dispersion of star forming galaxies can be entirely accounted by the gravitational potential of host galaxies, AGNs clearly show non-gravitational kinematics, which is comparable to or stronger than the virial motion caused by the gravitational potential. Second, the distribution in the [OIII] velocity - velocity dispersion diagram dramatically expands toward large values with increasing AGN luminosity, implying that the outflows are AGN-driven. Third, the fraction of AGNs with a signature of outflow kinematics, steeply increases with AGN luminosity and Eddington ratio. In particular, the majority of luminous AGNs presents strong non-gravitational kinematics in the [OIII] profile. Interestingly, we find that the specific star formation of non-outflow AGNs is much lower than that of strong outflow AGNs, while the star formation rate of strong outflow AGNs is comparable to that of star forming galaxies. We interpret this trend as a delayed AGN feedback as it takes dynamical time for the outflows to suppress star formation in galactic scales.

  17. The Close AGN Reference Survey (CARS)

    Science.gov (United States)

    Husemann, B.; Tremblay, G.; Davis, T.; Busch, G.; McElroy, R.; Neumann, J.; Urrutia, T.; Krumpe, M.; Scharwächter, J.; Powell, M.; Perez-Torres, M.; The CARS Team

    2017-09-01

    The role of active galactic nuclei (AGN) in the evolution of galaxies remains a mystery. The energy released by these accreting supermassive black holes can vastly exceed the entire binding energy of their host galaxies, yet it remains unclear how this energy is dissipated throughout the galaxy, and how that might couple to the galaxy's evolution. The Close AGN Reference Survey (CARS) is a multi-wavelength survey of a representative sample of luminous Type I AGN at redshifts 0.01 connection. These AGN are more luminous than very nearby AGN but are still close enough for spatially resolved mapping at sub-kpc scales with various state- of-the art facilities and instruments, such as VLT-MUSE, ALMA, JVLA, Chandra, SOFIA, and many more. In this article we showcase the power of CARS with examples of a multi-phase AGN outflow, diverse views on star formation activity and a unique changing-look AGN. CARS will provide an essential low-redshift reference sample for ongoing and forthcoming AGN surveys at high redshift.

  18. SWIFT BAT Survey of AGN

    Science.gov (United States)

    Tueller, J.; Mushotzky, R. F.; Barthelmy, S.; Cannizzo, J. K.; Gehrels, N.; Markwardt, C. B.; Skinner, G. K.; Winter, L. M.

    2008-01-01

    We present the results1 of the analysis of the first 9 months of data of the Swift BAT survey of AGN in the 14-195 keV band. Using archival X-ray data or follow-up Swift XRT observations, we have identified 129 (103 AGN) of 130 objects detected at [b] > 15deg and with significance > 4.8-delta. One source remains unidentified. These same X-ray data have allowed measurement of the X-ray properties of the objects. We fit a power law to the logN - log S distribution, and find the slope to be 1.42+/-0.14. Characterizing the differential luminosity function data as a broken power law, we find a break luminosity logL*(ergs/s)= 43.85+/-0.26. We obtain a mean photon index 1.98 in the 14-195 keV band, with an rms spread of 0.27. Integration of our luminosity function gives a local volume density of AGN above 10(exp 41) erg/s of 2.4x10(exp -3) Mpc(sup -3), which is about 10% of the total luminous local galaxy density above M* = -19.75. We have obtained X-ray spectra from the literature and from Swift XRT follow-up observations. These show that the distribution of log nH is essentially flat from nH = 10(exp 20)/sq cm to 10(exp 24)/sq cm, with 50% of the objects having column densities of less than 10(exp 22)/sq cm. BAT Seyfert galaxies have a median redshift of 0.03, a maximum log luminosity of 45.1, and approximately half have log nH > 22.

  19. Unifying Physics

    Science.gov (United States)

    Goradia, Shantilal

    2013-04-01

    Century old GR fails to unify quantum physics, nuclear force or distinguish between the mass of living bodies from inert mass. Probabilistic gravity [1] explains strong coupling (nuclear force). The natural log of the age of the universe, 10E60 in Planck times, equaling 137 (1/Alpha) extends physics to deeper science, if we stand on the shoulders of giants like Feynman and Gamow. Implications of [1] are that it is not the earth, but M and S numbers of the particles of the earth are remotely interacting with corresponding numbers of the particles of the moon and the sun respectively, neglecting other heavenly bodies in this short draft. This new physics is likely to enable creative scientific minds to throw light on a theoretical basis for an otherwise arbitrary cosmological constant, uniformity of microwave background, further vindication of Boltzmann, quantum informatics, Einstein’s later publicized views and more, eliminating the need to spend money for implicitly nonexistent quantum gravity and graviton.[4pt] [1] Journal of Physical Science and Applications 2 (7) (2012) 265-268.

  20. Studying AGN Jets At Extreme Angular Resolution

    Science.gov (United States)

    Bruni, Gabriele

    2016-10-01

    RadioAstron is a 10m antenna orbiting on the Russian Speckt-R spacecraft, launched in 2011. Performing radio interferometry with a global array of ground telescopes, it is providing record angular resolution. The Key Science Project on AGN polarization is exploiting it to study in great detail the configuration of magnetic fields in AGN jets, and understand their formation and collimation. To date, the project has already achieved the highest angular resolution image ever obtained in Astronomy, and detected brightness temperatures exceeding the ones predicted by theory of AGN.

  1. The Many Routes to AGN Feedback

    Energy Technology Data Exchange (ETDEWEB)

    Morganti, Raffaella, E-mail: morganti@astron.nl [ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo (Netherlands); Kapteyn Astronomical Institute, University of Groningen, Groningen (Netherlands)

    2017-11-29

    The energy released by Active Galactic Nuclei (AGN) in the form of radiation, winds, or radio plasma jets, is known to impact on the surrounding interstellar medium. The result of these processes, known as AGN (negative) feedback, is suggested to prevent gas, in and around galaxies, from cooling, and to remove, or at least redistribute, gas by driving massive and fast outflows, hence playing a key role in galaxy evolution. Given its importance, a large effort is devoted by the astronomical community to trace the effects of AGN on the surrounding gaseous medium and to quantify their impact for different types of AGN. This review briefly summarizes some of the recent observational results obtained in different wavebands, tracing different phases of the gas. I also summarize the new insights they have brought, and the constraints they provide to numerical simulations of galaxy formation and evolution. The recent addition of deep observations of cold gas and, in particular, of cold molecular gas, has brought some interesting surprises and has expanded our understanding of AGN and AGN feedback.

  2. The many routes to AGN feedback

    Science.gov (United States)

    Morganti, Raffaella

    2017-11-01

    The energy released by Active Galactic Nuclei (AGN) in the form of radiation, winds or radio plasma jets, is known to impact on the surrounding interstellar medium. The result of these processes, known as AGN (negative) feedback, is suggested to prevent gas, in and around galaxies, from cooling, and to remove, or at least redistribute, gas by driving massive and fast outflows, hence playing a key role in galaxy evolution. Given its importance, a large effort is devoted by the astronomical community to trace the effects of AGN on the surrounding gaseous medium and to quantify their impact for different types of AGN. This review briefly summarizes some of the recent observational results obtained in different wavebands, tracing different phases of the gas. I also summarise new insights they have brought, and the constraints they provide to numerical simulations of galaxy formation and evolution. The recent addition of deep observations of cold gas and, in particular, of cold molecular gas, has brought some interesting surprises and has expanded our understanding of AGN and AGN feedback.

  3. Searching for faint AGN in the CDFS: an X-ray (Chandra) vs optical variability (HST) comparison.

    Science.gov (United States)

    Georgantopoulos, I.; Pouliasis, E.; Bonanos, A.; Sokolovsky, K.; Yang, M.; Hatzidimitriou, D.; Bellas, I.; Gavras, P.; Spetsieri, Z.

    2017-10-01

    X-ray surveys are believed to be the most efficient way to detect AGN. Recently though, optical variability studies are claimed to probe even fainter AGN. We are presenting results from an HST study aimed to identify Active Galactic Nuclei (AGN) through optical variability selection in the CDFS.. This work is part of the 'Hubble Catalogue of Variables'project of ESA that aims to identify variable sources in the Hubble Source Catalogue.' In particular, we used Hubble Space Telescope (HST) z-band images taken over 5 epochs and performed aperture photometry to derive the lightcurves of the sources. Two statistical methods (standard deviation & interquartile range) resulting in a final sample of 175 variable AGN candidates, having removed the artifacts by visual inspection and known stars and supernovae. The fact that the majority of the sources are extended and variable indicates AGN activity. We compare the efficiency of the method by comparing with the 7Ms Chandra detections. Our work shows that the optical variability probes AGN at comparable redshifts but at deeper optical magnitudes. Our candidate AGN (non detected in X-rays) have luminosities of L_x<6×10^{40} erg/sec at z˜0.7 suggesting that these are associated with low luminosity Seyferts and LINERS.

  4. Experimental status of unified theories

    International Nuclear Information System (INIS)

    Bilen'kij, S.M.

    1979-01-01

    A standard SU(2)xU(1) theory is discussed. It is based on an assumption that the left components of fields form doublets, and the rignt ones - singlets. From the weak interaction lagrangian an expression is obtained for the effective hamiltonian describing neutrino-lepton processes. The results of discussing the experimental status of the unified theories of weak and electromagnetic interactions are in agreement with the simplest version of the unified theories - the Weinberg-Salam theory. It has been noted that the accuracy of the experiments (not exceeding 20%) is insufficient and no information is available on diagonal terms of the hamiltonian

  5. Extragalactic gamma-ray background from AGN winds and star-forming galaxies in cosmological galaxy-formation models

    Science.gov (United States)

    Lamastra, A.; Menci, N.; Fiore, F.; Antonelli, L. A.; Colafrancesco, S.; Guetta, D.; Stamerra, A.

    2017-10-01

    We derive the contribution to the extragalactic gamma-ray background (EGB) from active galactic nuclei (AGN) winds and star-forming galaxies by including a physical model for the γ-ray emission produced by relativistic protons accelerated by AGN-driven and supernova-driven shocks into a state-of-the-art semi-analytic model of galaxy formation. This is based on galaxy interactions as triggers of AGN accretion and starburst activity and on expanding blast waves as the mechanism to communicate outwards the energy injected into the interstellar medium by the active nucleus. We compare the model predictions with the latest measurement of the EGB spectrum performed by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi) in the range between 100 MeV and 820 GeV. We find that AGN winds can provide 35 ± 15% of the observed EGB in the energy interval Eγ = 0.1-1 GeV, for 73 ± 15% at Eγ = 1-10 GeV, and for 60 ± 20% at Eγ ≳10 GeV. The AGN wind contribution to the EGB is predicted to be larger by a factor of 3-5 than that provided by star-forming galaxies (quiescent plus starburst) in the hierarchical clustering scenario. The cumulative γ-ray emission from AGN winds and blazars can account for the amplitude and spectral shape of the EGB, assuming the standard acceleration theory, and AGN wind parameters that agree with observations. We also compare the model prediction for the cumulative neutrino background from AGN winds with the most recent IceCube data. We find that for AGN winds with accelerated proton spectral index p = 2.2-2.3, and taking into account internal absorption of γ-rays, the Fermi-LAT and IceCube data could be reproduced simultaneously.

  6. Unified Internet Messaging

    OpenAIRE

    Healy, Paul; Barber, Declan

    2015-01-01

    As telephony services, mobile services and internet services continue to converge, the prospect of providing Unified Messaging and even Unified Communications becomes increasingly achievable. This paper discusses the growing importance of IP-based networks to Unified Messaging developments and examines some of the key services and protocols that are likely to make Unified Messaging more widely available. In this initial paper, we limit ourselves initially to the unification of text-based mess...

  7. AGN feedback compared: jets versus radiation

    Science.gov (United States)

    Cielo, Salvatore; Bieri, Rebekka; Volonteri, Marta; Wagner, Alexander Y.; Dubois, Yohan

    2018-06-01

    Feedback by active galactic nuclei (AGNs) is often divided into quasar and radio mode, powered by radiation or radio jets, respectively. Both are fundamental in galaxy evolution, especially in late-type galaxies, as shown by cosmological simulations and observations of jet-ISM (interstellar medium) interactions in these systems. We compare AGN feedback by radiation and by collimated jets through a suite of simulations, in which a central AGN interacts with a clumpy, fractal galactic disc. We test AGNs of 1043 and 1046 erg s-1, considering jets perpendicular or parallel to the disc. Mechanical jets drive the more powerful outflows, exhibiting stronger mass and momentum coupling with the dense gas, while radiation heats and rarefies the gas more. Radiation and perpendicular jets evolve to be quite similar in outflow properties and effect on the cold ISM, while inclined jets interact more efficiently with all the disc gas, removing the densest 20 {per cent} in 20 Myr, and thereby reducing the amount of cold gas available for star formation. All simulations show small-scale inflows of 0.01-0.1 M⊙ yr-1, which can easily reach down to the Bondi radius of the central supermassive black hole (especially for radiation and perpendicular jets), implying that AGNs modulate their own duty cycle in a feedback/feeding cycle.

  8. Characterisation of a candidate dual AGN

    Science.gov (United States)

    Lena, D.; Panizo-Espinar, G.; Jonker, P. G.; Torres, M.; Heida, M.

    2018-05-01

    We present Chandra and optical observations of a candidate dual AGN discovered serendipitously while searching for recoiling black holes via a cross-correlation between the serendipitous XMM source catalog (2XMMi) and SDSS-DR7 galaxies with a separation no larger than ten times the sum of their Petrosian radii. The system has a stellar mass ratio M1/M2 ≈ 0.7. One of the galaxies (Source 1) shows clear evidence for AGN activity in the form of hard X-ray emission and optical emission-line diagnostics typical of AGN ionisation. The nucleus of the other galaxy (Source 2) has a soft X-ray spectrum, bluer colours, and optical emission line ratios dominated by stellar photoionisation with a "composite" signature, which might indicate the presence of a weak AGN. When plotted on a diagram with X-ray luminosity vs [OIII] luminosity both nuclei fall within the locus defined by local Seyfert galaxies. From the optical spectrum we estimate the electron densities finding n1 active nature of Source 1 can be established with confidence, whether the nucleus of Source 2 is active remains a matter of debate. Evidence that a faint AGN might reside in its nucleus is, however, tantalising.

  9. ACHP | Unified Federal Review

    Science.gov (United States)

    Search skip specific nav links Home arrow Unified Federal Review Three logos: 1) Executive Office of the Homeland Security. Unified Federal Environmental and Historic Preservation Review Process Please visit the new location for the Unified Federal Review located here: http://www.fema.gov/environmental-historic

  10. The BAT AGN Spectroscopic Survey (BASS) DR1-Spectral Measurements, Derived Quantities, and AGN Demographics

    Science.gov (United States)

    Koss, Michael; BASS Team

    2018-01-01

    We present the first catalog and data release of the Swift-BAT AGN Spectroscopic Survey (BASS). We analyze optical spectra of the majority of AGN (77%, 641/836) detected based on their 14-195 keV emission in the 70-month Swift BAT all-sky catalog. This includes redshift determination, absorption and emission line measurements, and black hole mass and accretion rate estimates for the majority of obscured and un-obscured AGN (74%, 473/641) with 340 measured for the first time. With ~90% of sources at z10^21.9 cm^-2. Seyfert 1.9 show a range of column densities. Compared to narrow line AGN in the SDSS, the X-ray selected AGN have a larger fraction of dusty host galaxies suggesting these types of AGN are missed in optical surveys. Using the most sensitive [OIII]/Hbeta and [NII]/Halpha emission line diagnostic, about half of the sources are classified as Seyferts, ~15% reside in dusty galaxies that lack an Hbeta detection, but for which the line upper limits imply either a Seyfert or LINER, ~15% are in galaxies with weak or no emission lines despite high quality spectra, and a few percent each are LINERS, composite galaxies, HII regions, or in known beamed AGN.

  11. Satellites of radio AGN in SDSS: Insights into agn triggering and feedback

    Energy Technology Data Exchange (ETDEWEB)

    Pace, Cameron; Salim, Samir, E-mail: cjpace@indiana.edu, E-mail: salims@indiana.edu [Indiana University, Department of Astronomy, Swain Hall West 319, Bloomington, IN 47405-7105 (United States)

    2014-04-10

    We study the effects of radio jets on galaxies in their vicinity (satellites) and the role of satellites in triggering radio-loud active galactic nuclei (AGNs). The study compares the aggregate properties of satellites of a sample of 7220 radio AGNs at z < 0.3 (identified by Best and Heckman from the SDSS and NVSS+FIRST surveys) to the satellites of a control sample of radio-quiet galaxies, which are matched in redshift, color, luminosity, and axis ratio, as well as by environment type: field galaxies, cluster members, and brightest cluster galaxies (BCGs). Remarkably, we find that radio AGNs exhibit on average a 50% excess (17σ significance) in the number of satellites within 100 kpc even though the cluster membership was controlled (e.g., radio BCGs have more satellites than radio-quiet BCGs, etc.). Satellite excess is not confirmed for high-excitation sources, which are only 2% of radio AGN. Extra satellites may be responsible for raising the probability for hot gas AGN accretion via tidal effects or may otherwise enhance the intensity or duration of the radio-emitting phase. Furthermore, we find that the incidence of radio AGNs among potential hosts (massive ellipticals) is similar for field galaxies and for non-BCG cluster members, suggesting that AGN fueling depends primarily on conditions in the host halo rather than the parent, cluster halo. Regarding feedback, we find that radio AGNs, either high or low excitation, have no detectable effect on star formation in their satellites, as neither induced star formation nor star formation quenching is present in more than ∼1% of radio AGN.

  12. Satellites of radio AGN in SDSS: Insights into agn triggering and feedback

    International Nuclear Information System (INIS)

    Pace, Cameron; Salim, Samir

    2014-01-01

    We study the effects of radio jets on galaxies in their vicinity (satellites) and the role of satellites in triggering radio-loud active galactic nuclei (AGNs). The study compares the aggregate properties of satellites of a sample of 7220 radio AGNs at z < 0.3 (identified by Best and Heckman from the SDSS and NVSS+FIRST surveys) to the satellites of a control sample of radio-quiet galaxies, which are matched in redshift, color, luminosity, and axis ratio, as well as by environment type: field galaxies, cluster members, and brightest cluster galaxies (BCGs). Remarkably, we find that radio AGNs exhibit on average a 50% excess (17σ significance) in the number of satellites within 100 kpc even though the cluster membership was controlled (e.g., radio BCGs have more satellites than radio-quiet BCGs, etc.). Satellite excess is not confirmed for high-excitation sources, which are only 2% of radio AGN. Extra satellites may be responsible for raising the probability for hot gas AGN accretion via tidal effects or may otherwise enhance the intensity or duration of the radio-emitting phase. Furthermore, we find that the incidence of radio AGNs among potential hosts (massive ellipticals) is similar for field galaxies and for non-BCG cluster members, suggesting that AGN fueling depends primarily on conditions in the host halo rather than the parent, cluster halo. Regarding feedback, we find that radio AGNs, either high or low excitation, have no detectable effect on star formation in their satellites, as neither induced star formation nor star formation quenching is present in more than ∼1% of radio AGN.

  13. The AGN Population in Nearby Galaxies

    International Nuclear Information System (INIS)

    Filho, Mercedes; Barthel, Peter; Ho, Luis

    2006-01-01

    In order to determine the incidence of black hole accretion-driven nuclear activity in nearby galaxies, we have compiled radio data for the LINERs, composite LINER,/Hn and Seyfert galaxies from a complete magnitude-limited sample of bright nearby galaxies (Palomar sample). Our results show an overall radio detection rate of 54% (22% of all bright nearby galaxies) and we estimate that at least ∼50% (∼20% of all bright nearby galaxies) are true AGN. By comparing the radio luminosity function of the LINERs, composite LINER/Hll and Seyferts galaxies in the Palomar sample with those of selected moderate-redshift AGN, we fhd that our sources naturally extend the radio luminosity function of powerful AGN down to powers of about 10 times that of Sgr A*

  14. Can CMB Surveys Help the AGN Community?

    Directory of Open Access Journals (Sweden)

    Bruce Partridge

    2017-08-01

    Full Text Available Contemporary projects to measure anisotropies in the cosmic microwave background (CMB are now detecting hundreds to thousands of extragalactic radio sources, most of them blazars. As a member of a group of CMB scientists involved in the construction of catalogues of such sources and their analysis, I wish to point out the potential value of CMB surveys to studies of AGN jets and their polarization. Current CMB projects, for instance, reach mJy sensitivity, offer wide sky coverage, are “blind” and generally of uniform sensitivity across the sky (hence useful statistically, make essentially simultaneous multi-frequency observations at frequencies from 30 to 857 GHz, routinely offer repeated observations of sources with interesting cadences and now generally provide polarization measurements. The aim here is not to analyze in any depth the AGN science already derived from such projects, but rather to heighten awareness of their promise for the AGN community.

  15. Search for AGN neutrinos with the Soudan 2 detector

    International Nuclear Information System (INIS)

    DeMuth, D.M.

    1997-05-01

    Several authors have presented models for neutrino production from Active Galactic Nuclei (AGN) that allow for the possibility of AGN neutrinos outnumbering the atmospheric neutrino flux for energies in excess of 30 TeV. Preliminary results from a search for high energy neutrinos from AGN using the underground Soudan 2 Detector are presented

  16. AGN Heating Through Cavities and Shocks

    NARCIS (Netherlands)

    Nulsen, P.E.J.; Jones, C.; Forman, W.R.; David, L.P.; McNamara, B.R.; Rafferty, D.A.; Bîrzan, L.; Wise, M.

    2007-01-01

    Three comments are made on AGN heating of cooling flows. A simple physical argument is used to show that the enthalpy of a buoyant radio lobe is converted to heat in its wake. Thus, a significant part of ``cavity'' enthalpy is likely to end up as heat. Second, the properties of the repeated weak

  17. The AGN Luminosity Fraction in Galaxy Mergers

    Science.gov (United States)

    Dietrich, Jeremy; Weiner, Aaron; Ashby, Matthew; Martinez-Galarza, Juan Rafael; Smith, Howard Alan

    2017-01-01

    Galaxy mergers are key events in galaxy evolution, generally triggering massive starbursts and AGNs. However, in these chaotic systems, it is not yet known what fraction each of these two mechanisms contributes to the total luminosity. Here we measure and model spectral energy distributions (SEDs) using the Code for Investigating Galaxy Emission (CIGALE) in up to 33 broad bands from the UV to the far-IR for 23 IR-luminous galaxies to estimate the fraction of the bolometric IR luminosity that can be attributed to the AGN. The galaxies are split nearly evenly into two subsamples: late-stage mergers, found in the IRAS Revised Bright Galaxy Sample or Faint Source Catalog, and early-stage mergers found in the Spitzer Interacting Galaxy Sample. We find that the AGN contribution to the total IR luminosity varies greatly from system to system, from 0% up to ~90%, but is substantially greater in the later-stage and brighter mergers. This is consistent with what is known about galaxy evolution and the triggering of AGNs.The SAO REU program is funded in part by the National Science Foundation REU and Department of Defense ASSURE programs under NSF Grant no. 1262851, and by the Smithsonian Institution.

  18. AGN Feedback Compared: Jets versus Radiation

    Science.gov (United States)

    Cielo, Salvatore; Bieri, Rebekka; Volonteri, Marta; Wagner, Alexander Y.; Dubois, Yohan

    2018-03-01

    Feedback by Active Galactic Nuclei is often divided into quasar and radio mode, powered by radiation or radio jets, respectively. Both are fundamental in galaxy evolution, especially in late-type galaxies, as shown by cosmological simulations and observations of jet-ISM interactions in these systems. We compare AGN feedback by radiation and by collimated jets through a suite of simulations, in which a central AGN interacts with a clumpy, fractal galactic disc. We test AGN of 1043 and 1046 erg/s, considering jets perpendicular or parallel to the disc. Mechanical jets drive the more powerful outflows, exhibiting stronger mass and momentum coupling with the dense gas, while radiation heats and rarifies the gas more. Radiation and perpendicular jets evolve to be quite similar in outflow properties and effect on the cold ISM, while inclined jets interact more efficiently with all the disc gas, removing the densest 20% in 20 Myr, and thereby reducing the amount of cold gas available for star formation. All simulations show small-scale inflows of 0.01 - 0.1 M⊙/yr, which can easily reach down to the Bondi radius of the central supermassive black hole (especially for radiation and perpendicular jets), implying that AGN modulate their own duty cycle in a feedback/feeding cycle.

  19. AGN UNIFICATION AT z ∼ 1: u - R COLORS AND GRADIENTS IN X-RAY AGN HOSTS

    International Nuclear Information System (INIS)

    Mark Ammons, S.; Rosario, David J. V.; Koo, David C.

    2011-01-01

    We present uncontaminated rest-frame u - R colors of 78 X-ray-selected active galactic nucleus (AGN) hosts at 0.5 1.1 kpc. These three observations imply that AGN obscuration is uncorrelated with the star formation rate beyond ∼1 kpc. These observations favor a unification scenario for intermediate-luminosity AGNs in which obscuration is determined geometrically. Scenarios in which the majority of intermediate-luminosity AGNs at z ∼ 1 are undergoing rapid, galaxy-wide quenching due to AGN-driven feedback processes are disfavored.

  20. Observational Signatures Of Agn Feedback Across Cosmic Time

    Science.gov (United States)

    Wylezalek, Dominika

    2017-06-01

    While many compelling models of AGN feedback exist, there is no clear data-driven picture of how winds are launched, how they propagate through the galaxy and what impact they have on the galactic gas. Recent work suggests that AGN luminosity plays an important role. The following described projects focus on understanding the power, reach and impact of feedback processes exerted by AGN of different power. I first describe recent efforts in our group of relating feedback signatures in powerful quasars to the specific star formation rate in their host galaxies, where our results are consistent with the AGN having a `negative' impact through feedback on the galaxies' star formation history. Feedback signatures seem to be best observable in gas-rich galaxies where the coupling of the AGN-driven wind to the gas is strongest, in agreement with recent simulations. But how and where does this quenching happen? Is it accomplished through the mechanical action of jets or through nuclear winds driven by radiation pressure? Finally, I show that AGN signatures and AGN-driven winds can be easily hidden and not be apparent in the integrated spectrum of a galaxy hosting a low/intermediate-luminosity AGN. Using data from the new SDSS-IV MaNGA survey, we have developed a new AGN selection algorithm tailored to IFU data and we are uncovering a much more nuanced picture of AGN activity allowing us to discover AGN signatures at large distances from the galaxy center. This implies that large IFU surveys, such as the SDSS-IV MaNGA survey, might uncover many previously unknown AGN and feedback signatures related to them. Outflows and feedback from low- and intermediate-luminosity AGN might have been underestimated in the past but can potentially significantly contribute to the AGN/host-galaxy self-regulation.

  1. HOW DOES RADIO AGN FEEDBACK FEED BACK?

    International Nuclear Information System (INIS)

    De Young, David S.

    2010-01-01

    The possible role of radio active galactic nucleus (AGN) 'feedback' in conventional hierarchical cosmological models has become widely discussed. This paper examines some of the details of how such feedback might work. A basic requirement is the conversion of radio AGN outflow energy into heating of the circumgalactic medium in a time comparable to the relevant cooling times. First, the class of radio AGN relevant to this process is identified as FR-I radio sources. Second, it is argued via comparisons with experimental data that these AGN outflows are strongly decelerated and become fully turbulent sonic or subsonic flows due to their interaction with the surrounding medium. Using this, a three-dimensional time-dependent calculation of the evolution of such turbulent magnetohydrodynamic flows is made to determine the time scale required for conversion of the turbulent energy into heat. This calculation, when coupled with observational data, suggests that the onset of heating can occur ∼10 8 yr after the fully turbulent flow is established, and this time is less than or comparable to the local cooling times in the interstellar or circumgalactic medium for many of these objects. The location of where heat deposition occurs remains uncertain, but estimates of outflow speeds suggest that heating may occur many tens of kpc from the center of the parent galaxy. Recent observations suggest that such radio AGN outflows may become dispersed on much larger scales than previously thought, thus possibly satisfying the requirement that heating occurs over a large fraction of the volume occupied by the circumgalactic gas.

  2. Tracing Supermassive Black Hole Growth with Offset and Dual AGN

    Science.gov (United States)

    Comerford, Julia

    The growth of supermassive black holes is tied to the evolution of their host galaxies, but we are still missing a fundamental understanding of how and when supermassive black holes build up their mass. Black hole mass growth can be traced when the black holes are powered as active galactic nuclei (AGN), and AGN activity can be triggered by the stochastic accretion of gas or by gas inflows driven by galaxy mergers. Galaxy merger simulations make a series of predictions about the AGN that are triggered by mergers: (1) major mergers preferentially trigger higher-luminosity AGN, (2) minor mergers more often trigger AGN activity in one supermassive black hole while major mergers more often trigger AGN activity in both black holes in a merger, and (3) black hole mass growth peaks when the black holes approach the center (theory have been limited by the difficulty in defining a clean observational sample of AGN in galaxy mergers and the observational challenge of spatially resolving two AGN with small (dual AGN as a new observational tool that can be used to address how and when supermassive black hole mass growth occurs. A merger of two galaxies brings two supermassive black holes together, and the two black holes exist at kpc-scale separations for 100 Myr before ultimately merging. While the black holes are at kpc-scale separations, they are known as dual AGN when both of them are fueled as AGN and offset AGN when only one is fueled as an AGN. Since offset and dual AGN only occur in galaxy mergers, by their very definition, they provide a clean observational sample of black hole mass growth in galaxy mergers. The small, kpc-scale separations of offset and dual AGN also enable an observational test of black hole fueling near the centers of merger-remnant galaxies. The full potential of offset and dual AGN for such studies of black hole mass growth has not yet been realized, due to the small number of such systems known. To date, only 13 confirmed offset and dual AGN are

  3. Changing-Look AGNs or Short-Lived Radio Sources?

    Energy Technology Data Exchange (ETDEWEB)

    Wołowska, Aleksandra [Toruń Centre for Astronomy, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Toruń (Poland); Kunert-Bajraszewska, Magdalena; Mooley, Kunal [Centre for Astrophysical Surveys, University of Oxford, Oxford (United Kingdom); Hallinan, Gregg, E-mail: ola@astro.umk.pl [Cahill Center for Astronomy, California Institute of Technology, Pasadena, CA (United States)

    2017-11-17

    The evolution of extragalactic radio sources has been a fundamental problem in the study of active galactic nuclei for many years. A standard evolutionary model has been created based on observations of a wide range of radio sources. In the general scenario of the evolution, the younger and smaller Gigahertz-Peaked Spectrum (GPS) and Compact Steep Spectrum (CSS) sources become large-scale FRI and FRII objects. However, a growing number of observations of low power radio sources suggests that the model cannot explain all their properties and there are still some aspects of the evolutionary path that remain unclear. There are indications, that some sources may be short-lived objects on timescales of 10{sup 4}–10{sup 5} years. Those objects represent a new population of active galaxies. Here, we present the discovery of several radio transient sources on timescales of 5–20 yrs, largely associated with renewed AGN (Active Galactic Nucleus) activity. These changing-look AGNs possibly represent behavior typical for many active galaxies.

  4. Star Formation of Merging Disk Galaxies with AGN Feedback Effects

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jongwon; Smith, Rory; Yi, Sukyoung K., E-mail: jw.park@yonsei.ac.kr [Department of Astronomy and Yonsei University Observatory, Yonsei University, Seoul 03722 (Korea, Republic of)

    2017-08-20

    Using a numerical hydrodynamics code, we perform various idealized galaxy merger simulations to study the star formation (SF) of two merging disk galaxies. Our simulations include gas accretion onto supermassive black holes and active galactic nucleus (AGN) feedback. By comparing AGN simulations with those without AGNs, we attempt to understand when the AGN feedback effect is significant. Using ∼70 simulations, we investigate SF with the AGN effect in mergers with a variety of mass ratios, inclinations, orbits, galaxy structures, and morphologies. Using these merger simulations with AGN feedback, we measure merger-driven SF using the burst efficiency parameter introduced by Cox et al. We confirm previous studies which demonstrated that, in galaxy mergers, AGN suppresses SF more efficiently than in isolated galaxies. However, we also find that the effect of AGNs on SF is larger in major than in minor mergers. In minor merger simulations with different primary bulge-to-total ratios, the effect of bulge fraction on the merger-driven SF decreases due to AGN feedback. We create models of Sa-, Sb-, and Sc-type galaxies and compare their SF properties while undergoing mergers. With the current AGN prescriptions, the difference in merger-driven SF is not as pronounced as in the recent observational study of Kaviraj. We discuss the implications of this discrepancy.

  5. Star Formation of Merging Disk Galaxies with AGN Feedback Effects

    International Nuclear Information System (INIS)

    Park, Jongwon; Smith, Rory; Yi, Sukyoung K.

    2017-01-01

    Using a numerical hydrodynamics code, we perform various idealized galaxy merger simulations to study the star formation (SF) of two merging disk galaxies. Our simulations include gas accretion onto supermassive black holes and active galactic nucleus (AGN) feedback. By comparing AGN simulations with those without AGNs, we attempt to understand when the AGN feedback effect is significant. Using ∼70 simulations, we investigate SF with the AGN effect in mergers with a variety of mass ratios, inclinations, orbits, galaxy structures, and morphologies. Using these merger simulations with AGN feedback, we measure merger-driven SF using the burst efficiency parameter introduced by Cox et al. We confirm previous studies which demonstrated that, in galaxy mergers, AGN suppresses SF more efficiently than in isolated galaxies. However, we also find that the effect of AGNs on SF is larger in major than in minor mergers. In minor merger simulations with different primary bulge-to-total ratios, the effect of bulge fraction on the merger-driven SF decreases due to AGN feedback. We create models of Sa-, Sb-, and Sc-type galaxies and compare their SF properties while undergoing mergers. With the current AGN prescriptions, the difference in merger-driven SF is not as pronounced as in the recent observational study of Kaviraj. We discuss the implications of this discrepancy.

  6. The AGN-Star Formation Connection: Future Prospects with JWST

    Science.gov (United States)

    Kirkpatrick, Allison; Alberts, Stacey; Pope, Alexandra; Barro, Guillermo; Bonato, Matteo; Kocevski, Dale D.; Pérez-González, Pablo; Rieke, George H.; Rodríguez-Muñoz, Lucia; Sajina, Anna; Grogin, Norman A.; Mantha, Kameswara Bharadwaj; Pandya, Viraj; Pforr, Janine; Salvato, Mara; Santini, Paola

    2017-11-01

    The bulk of the stellar growth over cosmic time is dominated by IR-luminous galaxies at cosmic noon (z=1{--}2), many of which harbor a hidden active galactic nucleus (AGN). We use state-of-the-art infrared color diagnostics, combining Spitzer and Herschel observations, to separate dust-obscured AGNs from dusty star-forming galaxies (SFGs) in the CANDELS and COSMOS surveys. We calculate 24 μm counts of SFGs, AGN/star-forming “Composites,” and AGNs. AGNs and Composites dominate the counts above 0.8 mJy at 24 μm, and Composites form at least 25% of an IR sample even to faint detection limits. We develop methods to use the Mid-Infrared Instrument (MIRI) on JWST to identify dust-obscured AGNs and Composite galaxies from z˜ 1{--}2. With the sensitivity and spacing of MIRI filters, we will detect >4 times as many AGN hosts as with Spitzer/IRAC criteria. Any star formation rates based on the 7.7 μm PAH feature (likely to be applied to MIRI photometry) must be corrected for the contribution of the AGN, or the star formation rate will be overestimated by ˜35% for cases where the AGN provides half the IR luminosity and ˜50% when the AGN accounts for 90% of the luminosity. Finally, we demonstrate that our MIRI color technique can select AGNs with an Eddington ratio of {λ }{Edd}˜ 0.01 and will identify AGN hosts with a higher specific star formation rate than X-ray techniques alone. JWST/MIRI will enable critical steps forward in identifying and understanding dust-obscured AGNs and the link to their host galaxies.

  7. The AGN Nature of LINER Nuclear Sources

    Energy Technology Data Exchange (ETDEWEB)

    Márquez, Isabel; Masegosa, Josefa [Instituto de Astrofisica de Andalucia (CSIC), Granada (Spain); González-Martin, Omaira [Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, Morelia (Mexico); Hernández-Garcia, Lorena [Istituto di Astrofisica e Planetologia Spaziali, Rome (Italy); Pović, Mirjana [Instituto de Astrofisica de Andalucia (CSIC), Granada (Spain); Ethiopian Space Science and Technology Institute and Entoto Observatory and Research Center, Addis Ababa (Ethiopia); Netzer, Hagai [Raymond and Beverly Sackler Faculty of Exact Sciences, School of Physics and Astronomy and the Wise Observatory, Tel-Aviv University, Tel Aviv (Israel); Cazzoli, Sara; Olmo, Ascensión del, E-mail: isabel@iaa.es [Instituto de Astrofisica de Andalucia (CSIC), Granada (Spain)

    2017-11-16

    Low-ionization nuclear emission-line regions (LINERs) are specially interesting objects since not only they represent the most numerous local Active Galactic Nuclei population, but they could be the link between normal and active galaxies as suggested by their low X-ray luminosities. The origin of LINER nuclei being still controversial, our works, through a multiwavelength approach, have contributed, firstly, to confirm that a large number of nuclear LINERs in the local universe are AGN powered. Secondly, from the study of X-ray spectral variability, we found that long term variations are very common, and they are mostly related to hard energies (2–10keV). These variations might be due to changes in the absorber and/or intrinsic variations of the source. Thirdly, Mid-infrared (MIR) imaging also indicates that LINERs are the low luminosity end of AGN toward lower luminosities, and MIR spectroscopy shows that the average spectrum of AGN-dominated LINERs with X-ray luminosities L{sub X}(2–10 keV) > 10{sup 41} erg/s is similar to the average mid-IR spectrum of AGN-dominated Seyfert 2s; for fainter LINERS, their spectral shape suggests that the dusty-torus may disappear. Fourth, the extended Hα emission of LINERs at HST resolution indicates that they follow remarkably well the Narrow Line Region morphology and the luminosity-size relation obtained for Seyfert and QSOs; HST Hα morphology may suggest the presence of outflows, which could contribute to the line broadening, with the resulting consequences on the percentage of LINERs where the Broad Line Region is detected. This issue is being revisited by our group with a high spectral resolution set of optical data for nearby type-1 LINERs. Finally, concerning systematic studies on the role of star formation in LINERs, which are scarce, our contribution deals with the study of a sample of the most luminous, highest star formation rate LINERs in the local Universe (at z from 0.04 to 0.11), together with its comparison

  8. The AGN nature of LINER nuclear sources

    Science.gov (United States)

    Márquez, Isabel; Masegosa, Josefa; González-Martin, Omaira; Hernández-Garcia, Lorena; Pović, Mirjana; Netzer, Hagai; Cazzoli, Sara; del Olmo, Ascensión

    2017-11-01

    Low-ionization nuclear emission-line regions (LINERs) are specially interesting objects since not only they represent the most numerous local Active Galactic Nuclei population, but they could be the link between normal and active galaxies as suggested by their low X-ray luminosities. The origin of LINER nuclei being still controversial, our works, through a multiwavelength approach, have contributed, firstly, to confirm that a large number of nuclear LINERs in the local universe are AGN powered. Secondly, from the study of X-ray spectral variability, we found that long term variations are very common, and they are mostly related to hard energies (2-10 keV). These variations might be due to changes in the absorber and/or intrinsic variations of the source. Thirdly, Mid-infrared (MIR) imaging also indicates that LINERs are the low luminosity end of AGN towards lower luminosities, and MIR spectroscopy shows that the average spectrum of AGN-dominated LINERs with X-ray luminosities L_X(2-10 keV) > 10^{41} erg/s is similar to the average mid-IR spectrum of AGN-dominated Seyfert 2s; for fainter LINERS, their spectral shape suggests that the dusty-torus may disappear. Fourth, the extended Hα emission of LINERs at HST resolution indicates that they follow remarkably well the Narrow Line Region morphology and the luminosity-size relation obtained for Seyfert and QSOs; HST Hα morphology may suggest the presence of outflows, which could contribute to the line broadening, with the resulting consequences on the percentage of LINERs where the Broad Line Region is detected. This issue is being revisited by our group with a high spectral resolution set of optical data for nearby type-1 LINERs. Finally, concerning systematic studies on the role of star formation in LINERs, which are scarce, our contribution deals with the study of a sample of the most luminous, highest star formation rate LINERs in the local Universe (at z from 0.04 to 0.11), together with its comparison with both

  9. The AGN Nature of LINER Nuclear Sources

    International Nuclear Information System (INIS)

    Márquez, Isabel; Masegosa, Josefa; González-Martin, Omaira; Hernández-Garcia, Lorena; Pović, Mirjana; Netzer, Hagai; Cazzoli, Sara; Olmo, Ascensión del

    2017-01-01

    Low-ionization nuclear emission-line regions (LINERs) are specially interesting objects since not only they represent the most numerous local Active Galactic Nuclei population, but they could be the link between normal and active galaxies as suggested by their low X-ray luminosities. The origin of LINER nuclei being still controversial, our works, through a multiwavelength approach, have contributed, firstly, to confirm that a large number of nuclear LINERs in the local universe are AGN powered. Secondly, from the study of X-ray spectral variability, we found that long term variations are very common, and they are mostly related to hard energies (2–10keV). These variations might be due to changes in the absorber and/or intrinsic variations of the source. Thirdly, Mid-infrared (MIR) imaging also indicates that LINERs are the low luminosity end of AGN toward lower luminosities, and MIR spectroscopy shows that the average spectrum of AGN-dominated LINERs with X-ray luminosities L X (2–10 keV) > 10 41 erg/s is similar to the average mid-IR spectrum of AGN-dominated Seyfert 2s; for fainter LINERS, their spectral shape suggests that the dusty-torus may disappear. Fourth, the extended Hα emission of LINERs at HST resolution indicates that they follow remarkably well the Narrow Line Region morphology and the luminosity-size relation obtained for Seyfert and QSOs; HST Hα morphology may suggest the presence of outflows, which could contribute to the line broadening, with the resulting consequences on the percentage of LINERs where the Broad Line Region is detected. This issue is being revisited by our group with a high spectral resolution set of optical data for nearby type-1 LINERs. Finally, concerning systematic studies on the role of star formation in LINERs, which are scarce, our contribution deals with the study of a sample of the most luminous, highest star formation rate LINERs in the local Universe (at z from 0.04 to 0.11), together with its comparison with

  10. Microvariability in AGNs: study of different statistical methods - I. Observational analysis

    Science.gov (United States)

    Zibecchi, L.; Andruchow, I.; Cellone, S. A.; Carpintero, D. D.; Romero, G. E.; Combi, J. A.

    2017-05-01

    We present the results of a study of different statistical methods currently used in the literature to analyse the (micro)variability of active galactic nuclei (AGNs) from ground-based optical observations. In particular, we focus on the comparison between the results obtained by applying the so-called C and F statistics, which are based on the ratio of standard deviations and variances, respectively. The motivation for this is that the implementation of these methods leads to different and contradictory results, making the variability classification of the light curves of a certain source dependent on the statistics implemented. For this purpose, we re-analyse the results on an AGN sample observed along several sessions with the 2.15 m 'Jorge Sahade' telescope (CASLEO), San Juan, Argentina. For each AGN, we constructed the nightly differential light curves. We thus obtained a total of 78 light curves for 39 AGNs, and we then applied the statistical tests mentioned above, in order to re-classify the variability state of these light curves and in an attempt to find the suitable statistical methodology to study photometric (micro)variations. We conclude that, although the C criterion is not proper a statistical test, it could still be a suitable parameter to detect variability and that its application allows us to get more reliable variability results, in contrast with the F test.

  11. Obscured AGN at z ~ 1 from the zCOSMOS-Bright Survey. I. Selection and optical properties of a [Ne v]-selected sample

    Science.gov (United States)

    Mignoli, M.; Vignali, C.; Gilli, R.; Comastri, A.; Zamorani, G.; Bolzonella, M.; Bongiorno, A.; Lamareille, F.; Nair, P.; Pozzetti, L.; Lilly, S. J.; Carollo, C. M.; Contini, T.; Kneib, J.-P.; Le Fèvre, O.; Mainieri, V.; Renzini, A.; Scodeggio, M.; Bardelli, S.; Caputi, K.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Iovino, A.; Kampczyk, P.; Knobel, C.; Kovač, K.; Le Borgne, J.-F.; Le Brun, V.; Maier, C.; Pellò, R.; Peng, Y.; Perez Montero, E.; Presotto, V.; Silverman, J. D.; Tanaka, M.; Tasca, L.; Tresse, L.; Vergani, D.; Zucca, E.; Bordoloi, R.; Cappi, A.; Cimatti, A.; Koekemoer, A. M.; McCracken, H. J.; Moresco, M.; Welikala, N.

    2013-08-01

    sample of type 2 AGN is 43 ± 4% (statistical errors only), which agrees well with standard assumptions by XRB synthesis models.

  12. AGN Feedback and Its Quenching Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Combes, Francoise, E-mail: francoise.combes@obspm.fr [Observatoire de Paris, LERMA, Centre National de la Recherche Scientifique, College de France, PSL, Sorbonne University UPMC, Paris (France)

    2017-09-21

    In the last decade, observations have accumulated on gas outflows in galaxies, and in particular massive molecular ones. The mass outflow rate is estimated between 1 and 5 times the star formation rate. For the highest maximal velocities, they are driven by AGN; these outflows are therefore a clear way to moderate or suppress star formation. Some of the most convincing examples at low redshift come from the radio mode, when the radio jets are inclined toward the galaxy plane, or expand in the hot intra-cluster medium, in cool core clusters. However, AGN feedback can also be positive in many occasions, and the net effect is difficult to evaluate. The quenching efficiency is discussed in view of recent observations.

  13. CERN Library | Agnes Chavez @ CERN | 3 May

    CERN Multimedia

    CERN Library

    2016-01-01

    Agnes Chavez is an artist and educator participating in a two-week research stay through the ATLAS Experiment at CERN.   Tuesday 3 May at 4 p.m. CERN Library (52 1-052) Artist/educator, Agnes Chavez will share video outcomes from Projecting Particles, an Art + Science + Education collaboration with ATLAS. The Sci-Art project combines the International Masterclass with Projection Art in a series of teen-led youth workshops and projection events. In this presentation Chavez will share her vision and describe the research and development behind the project, now in its third year.  For the Projecting pARTicles series of art installations she has formed an interdisciplinary team of programmers, artists, scientists and educators to investigate how we can create art and education interventions inspired by emerging particle physics theories. Chavez’s art experiments with data visualization, sound and projections to create participatory environments. She collaborates with programmers t...

  14. AGN Science with STROBE-X

    Science.gov (United States)

    Ballantyne, David; Balokovic, Mislav; Garcia, Javier; Koss, Michael; STROBE-X

    2018-01-01

    The probe concept STROBE-X, with its combination of large collecting area, wide-field monitor, broad bandpass, and rapid timing capability, is a powerful tool for studying many aspects of AGN astrophysics. This unique combination of features opens up the possibility for studying AGNs in ways current and other future missions are unable to accomplish. Here, we show a few of the novel new investigations made possible by STROBE-X: probing the structure of the BLR and torus with reverberation of the narrow Fe Kα line and line-of-sight column density, tracking changes in coronal parameters, investigating the origin of the soft excess, Fe Kα emission line surveys, and efficient Compton-thick characterization. Additional ideas and suggestions are always welcome and can be communicated to any member of the STROBE-X team.

  15. Challenges in Finding AGNs in the Low Luminosity Regime

    Science.gov (United States)

    Satyapal, Shobita; Abel, Nick; Secrest, Nathan; Singh, Amrit; Ellison, Sara

    2016-08-01

    Low luminosity AGNs are an important component of the AGN population. They are often found in the lowest mass galaxies or galaxies that lack classical bulges, a demographic that places important constraints to models of supermassive black hole seed formation and merger-free models of AGN fueling. The detection of AGNs in this low luminosity regime is challenging both because star formation in the host galaxy can dominate the optical spectrum and gas and dust can obscure the central engine at both optical and X-ray wavelengths. Thus while mid-infrared color selection and X-ray observations at energies <10 keV are often powerful tools in uncovering optically unidentified AGNs at higher luminosities, this is not the case in the low luminosity regime. In this talk, I will review the effectiveness of uncovering AGNs in the low luminosity regime using multiwavength investigations, with a focus on infrared spectroscopic signatures.

  16. AGNES - safety reassessment of Paks NPP

    International Nuclear Information System (INIS)

    Gado, J.

    1995-01-01

    The main goal of the AGNES (Advanced General and New Evaluation of Safety) project for the reassessment of the safety of Paks Nuclear Power Plant, Hungary, was to improve the safety culture of the technology at Paks. A report was prepared on the reassessment of the Paks NPP safety. The analysis was divided into four groups: systems analysis, analysis of design basis accidents, severe accident analysis, and level 1 probabilistic safety analysis. Proposed safety enhancement measures are discussed. (N.T.)

  17. X-Rays and Infrared Selected AGN

    Science.gov (United States)

    Kirhakos, S. D.; Steiner, J. E.

    1990-11-01

    RESUMEN. En la busqueda de nucleos activos galacticos (NAG) oscurecidos, seleccionamos una tnuestra de galaxias ernisoras de rayos S infrarrojos, Ia mayoria de las cuales son vistas de perf ii. La 6ptica de la regi6n nuclear de las galaxias seleccionadas revelan que el 76% de ellas muestran lineas de emisi5n La clasificaci6n de los es- pectros de acuerdo a los anchos y a la intensidad de cocientes de lineas muestran que existen 34 NAG, 34 objetos de tipo de transici6n y 34 galaxias de la regi6n con nucleos de tipo regi6n H II. Entre los NAG, 3 son del tipo Seyfert I y las otras son del tipo 2. Sugerimos que los objetos identificados como NAG de llneas angostas son objetos tipo Seyfert I oscurecidos ABSTRACT. Looking for obscured active galactic nuclei (AGN), we selected a sample of infrarediX-rays emitting galaxies, mos"t of which are seen as edge-on. Optical spectroscopy of the nuclear region of the selected galaxies revealed that 76 % of them show emission l 'nes. Classification of the spectra according to the widths and line intensity ratios shows that there are 34 AGN, 34 transition type objects and 43 nuclear HIl-like region galaxies. Among the AGN, three are Seyfert type 1 and the others are type 2 objects. We suggest that the objects identified as narrow line AGN are obscured Seyfert 1. o'L : GALAXIES-ACTIVE - X-RAY S-GENERAL

  18. Impression Management Agnes Monica Melalui Akun Instagram (@Agnezmo)

    OpenAIRE

    Alim, Chelsea Amanda

    2014-01-01

    Penelitian ini dilakukan untuk menganalisa penggunaan taktik manajemen kesan yang dilakukan Agnes Monica melalui akun Instagram (@agnezmo). Agnes Monica sebagai seseorang yang berpengaruh, selalu menjadi bahan perbincangan publik, dan perhatian media sosial, memiliki kesan yang baik, termasuk melalui Instagram. Peneliti menggunakan metode analisis isi kuantitatif untuk menganalisa 45 post foto Instagram Agnes Monica, yang ada pada tanggal 1 Februari 2014 - 1 April 2014. Hasil penelitian ini ...

  19. HOT DUST OBSCURED GALAXIES WITH EXCESS BLUE LIGHT: DUAL AGN OR SINGLE AGN UNDER EXTREME CONDITIONS?

    Energy Technology Data Exchange (ETDEWEB)

    Assef, R. J.; Diaz-Santos, T. [Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago (Chile); Walton, D. J.; Brightman, M. [Space Radiation Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States); Stern, D.; Eisenhardt, P. R. M.; Tsai, C.-W. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Mail Stop 169-236, Pasadena, CA 91109 (United States); Alexander, D. [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Bauer, F. [Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile); Blain, A. W. [Physics and Astronomy, University of Leicester, 1 University Road, Leicester LE1 7RH (United Kingdom); Finkelstein, S. L. [The University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712 (United States); Hickox, R. C. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); Wu, J. W., E-mail: roberto.assef@mail.udp.cl [UCLA Astronomy, P.O. Box 951547, Los Angeles, CA 90095-1547 (United States)

    2016-03-10

    Hot dust-obscured galaxies (Hot DOGs) are a population of hyper-luminous infrared galaxies identified by the Wide-field Infrared Survey Explorer (WISE) mission from their very red mid-IR colors, and characterized by hot dust temperatures (T > 60 K). Several studies have shown clear evidence that the IR emission in these objects is powered by a highly dust-obscured active galactic nucleus (AGN) that shows close to Compton-thick absorption at X-ray wavelengths. Thanks to the high AGN obscuration, the host galaxy is easily observable, and has UV/optical colors usually consistent with those of a normal galaxy. Here we discuss a sub-population of eight Hot DOGs that show enhanced rest-frame UV/optical emission. We discuss three scenarios that might explain the excess UV emission: (i) unobscured light leaked from the AGN by reflection over the dust or by partial coverage of the accretion disk; (ii) a second unobscured AGN in the system; or (iii) a luminous young starburst. X-ray observations can help discriminate between these scenarios. We study in detail the blue excess Hot DOG WISE J020446.13–050640.8, which was serendipitously observed by Chandra/ACIS-I for 174.5 ks. The X-ray spectrum is consistent with a single, hyper-luminous, highly absorbed AGN, and is strongly inconsistent with the presence of a secondary unobscured AGN. Based on this, we argue that the excess blue emission in this object is most likely either due to reflection or a co-eval starburst. We favor the reflection scenario as the unobscured star formation rate needed to power the UV/optical emission would be ≳1000 M{sub ⊙} yr{sup −1}. Deep polarimetry observations could confirm the reflection hypothesis.

  20. HOT DUST OBSCURED GALAXIES WITH EXCESS BLUE LIGHT: DUAL AGN OR SINGLE AGN UNDER EXTREME CONDITIONS?

    International Nuclear Information System (INIS)

    Assef, R. J.; Diaz-Santos, T.; Walton, D. J.; Brightman, M.; Stern, D.; Eisenhardt, P. R. M.; Tsai, C.-W.; Alexander, D.; Bauer, F.; Blain, A. W.; Finkelstein, S. L.; Hickox, R. C.; Wu, J. W.

    2016-01-01

    Hot dust-obscured galaxies (Hot DOGs) are a population of hyper-luminous infrared galaxies identified by the Wide-field Infrared Survey Explorer (WISE) mission from their very red mid-IR colors, and characterized by hot dust temperatures (T > 60 K). Several studies have shown clear evidence that the IR emission in these objects is powered by a highly dust-obscured active galactic nucleus (AGN) that shows close to Compton-thick absorption at X-ray wavelengths. Thanks to the high AGN obscuration, the host galaxy is easily observable, and has UV/optical colors usually consistent with those of a normal galaxy. Here we discuss a sub-population of eight Hot DOGs that show enhanced rest-frame UV/optical emission. We discuss three scenarios that might explain the excess UV emission: (i) unobscured light leaked from the AGN by reflection over the dust or by partial coverage of the accretion disk; (ii) a second unobscured AGN in the system; or (iii) a luminous young starburst. X-ray observations can help discriminate between these scenarios. We study in detail the blue excess Hot DOG WISE J020446.13–050640.8, which was serendipitously observed by Chandra/ACIS-I for 174.5 ks. The X-ray spectrum is consistent with a single, hyper-luminous, highly absorbed AGN, and is strongly inconsistent with the presence of a secondary unobscured AGN. Based on this, we argue that the excess blue emission in this object is most likely either due to reflection or a co-eval starburst. We favor the reflection scenario as the unobscured star formation rate needed to power the UV/optical emission would be ≳1000 M ⊙ yr −1 . Deep polarimetry observations could confirm the reflection hypothesis

  1. Clustering Measurements of broad-line AGNs: Review and Future

    Directory of Open Access Journals (Sweden)

    Mirko Krumpe

    2014-12-01

    Full Text Available Despite substantial effort, the precise physical processes that lead to the growth of super-massive black holes in the centers of galaxies are still not well understood. These phases of black hole growth are thought to be of key importance in understanding galaxy evolution. Forthcoming missions such as eROSITA, HETDEX, eBOSS, BigBOSS, LSST, and Pan-STARRS will compile by far the largest ever Active Galactic Nuclei (AGNs catalogs which will allow us to measure the spatial distribution of AGNs in the universe with unprecedented accuracy. For the first time, AGN clustering measurements will reach a level of precision that will not only allow for an alternative approach to answering open questions in AGN and galaxy co-evolution but will open a new frontier, allowing us to precisely determine cosmological parameters. This paper reviews large-scale clustering measurements of broad line AGNs. We summarize how clustering is measured and which constraints can be derived from AGN clustering measurements, we discuss recent developments, and we briefly describe future projects that will deliver extremely large AGN samples which will enable AGN clustering measurements of unprecedented accuracy. In order to maximize the scientific return on the research fields of AGN and galaxy evolution and cosmology, we advise that the community develops a full understanding of the systematic uncertainties which will, in contrast to today’s measurement, be the dominant source of uncertainty.

  2. Hypercat - Hypercube of Clumpy AGN Tori

    Science.gov (United States)

    Nikutta, Robert; Lopez-Rodriguez, Enrique; Ichikawa, Kohei; Levenson, Nancy; Packham, Christopher C.

    2017-06-01

    Dusty tori surrounding the central engines of Active Galactic Nuclei (AGN) are required by the Unification Paradigm, and are supported by many observations, e.g. variable nuclear absorber (sometimes Compton-thick) in X-rays, reverberation mapping in optical/UV, hot dust emission and SED shapes in NIR/MIR, molecular and cool-dust tori observed with ALMA in sub-mm.While models of AGN torus SEDs have been developed and utilized for a long time, the study of the resolved emission morphology (brightness maps) has so far been under-appreciated, presumably because resolved observations of the central parsec in AGN are only possible very recently. Currently, only NIR+MIR interferometry is capable of resolving the nuclear dust emission (but not of producing images, until MATISSE comes online). Furthermore, MIR interferometry has delivered also puzzling results, e.g. that in some resolved sources the light emanates preferentially from polar directions above the "torus" system, and not from the equatorial plane, where most of the dust is located.We are preparing the release of a panchromatic, fully interpolable hypercube of brightness maps and projected dust images for a large number of CLUMPY torus models (Nenkova+2008), that will help facilitate studies of resolved AGN emission and dust morphologies. Together with the cube we will release a comprehensive set of open-source tools (Python) that will enable researches to work efficiently with this large hypercube:* easy sub-cube selection + memory-mapping (mitigating the too-big-for-RAM problem)* multi-dim image interpolation (get an image at any wavelength & model parameter combination)* simulation of observations with telescopes (compute/provide + apply a PSF) and interferometers (get visibilities)* analyze images with respect to the power contained at all scales and orientations (via 2D steerable wavelets), addressing the seemingly puzzling results mentioned aboveA series of papers is in preparation, aiming at solving the

  3. Fermi-LAT observation of nonblazar AGNs

    Science.gov (United States)

    Sahakyan, N.; Baghmanyan, V.; Zargaryan, D.

    2018-06-01

    Context. Fermi Large Area Telescope (Fermi-LAT) has recently detected γ-ray emission from active galactic nuclei (AGN) that do not show clear evidence for optical blazar characteristics or have jets pointing away from the observer (nonblazar AGNs). These are interesting γ-ray emitters providing an alternative approach to studying high energy emission processes. Aims: This paper investigates the spectral and temporal properties of γ-ray emission from nonblazar AGNs using the recent Fermi-LAT observational data. Methods: The data collected by Fermi-LAT during 2008-2015, from the observations of 26 nonblazar AGNs, including 11 Fanaroff-Riley Type I (FRI) and ten FRII radio galaxies and steep spectrum radio quasars (SSRQs) and five narrow line seyfert 1s (NLSy1s) are analysed using the new PASS 8 event selection and instrument response function. Possible spectral changes above GeV energies are investigated with a detailed spectral analysis. Light curves generated with normal and adaptive time bins are used to study the γ-ray flux variability. Results: Non-blazar AGNs have a γ-ray photon index in the range of 1.84-2.86 and a flux varying from a few times 10-9 photon cm-2 s-1 to 10-7 photon cm-2 s-1. Over long time periods, the power law provides an adequate description of the γ-ray spectra of almost all sources. Significant curvature is observed in the γ-ray spectra of NGC 1275, NGC 6251, SBS 0846 + 513, and PMN J0948 + 0022 and their spectra are better described by log parabola or by the power law with exponential cut-off models. The γ-ray spectra of PKS 0625-25 and 3C 380 show a possible deviation from a simple power-law shape, indicating a spectral cut-off around the observed photon energy of Ecut = 131.2 ± 88.04 GeV and Ecut = 55.57 ± 50.74 GeV, respectively. Our analysis confirms the previous finding of an unusual spectral turnover in the γ-ray spectrum of Cen A: the photon index changes from Γ = 2.75 ± 0.02 to 2.31 ± 0.1 at 2.35 ± 0.08 GeV. In the

  4. BAT AGN Spectroscopic Survey. VIII. Type 1 AGN with Massive Absorbing Columns

    Science.gov (United States)

    Shimizu, T. Taro; Davies, Richard I.; Koss, Michael; Ricci, Claudio; Lamperti, Isabella; Oh, Kyuseok; Schawinski, Kevin; Trakhtenbrot, Benny; Burtscher, Leonard; Genzel, Reinhard; Lin, Ming-yi; Lutz, Dieter; Rosario, David; Sturm, Eckhard; Tacconi, Linda

    2018-04-01

    We explore the relationship between X-ray absorption and optical obscuration within the BAT AGN Spectroscopic Survey (BASS), which has been collecting and analyzing the optical and X-ray spectra for 641 hard X-ray selected (E > 14 keV) active galactic nuclei (AGNs). We use the deviation from a linear broad Hα-to-X-ray relationship as an estimate of the maximum optical obscuration toward the broad line region (BLR) and compare the A V to the hydrogen column densities ({N}{{H}}) found through systematic modeling of their X-ray spectra. We find that the inferred columns implied by A V toward the BLR are often orders of magnitude less than the columns measured toward the X-ray emitting region, indicating a small-scale origin for the X-ray absorbing gas. After removing 30% of Sy 1.9s that potentially have been misclassified due to outflows, we find that 86% (164/190) of the Type 1 population (Sy 1–1.9) are X-ray unabsorbed as expected based on a single obscuring structure. However, 14% (26/190), of which 70% (18/26) are classified as Sy 1.9, are X-ray absorbed, suggesting that the BLR itself is providing extra obscuration toward the X-ray corona. The fraction of X-ray absorbed Type 1 AGNs remains relatively constant with AGN luminosity and Eddington ratio, indicating a stable BLR covering fraction.

  5. Spectral-luminosity evolution of active galactic nuclei (AGN)

    Science.gov (United States)

    Leiter, Darryl; Boldt, Elihu

    1992-01-01

    The origin of the cosmic X-ray and gamma-ray backgrounds is explained via the mechanism of AGN spectral-luminosity evolution. The spectral evolution of precursor active galaxies into AGN, and Newton-Raphson input and output parameters are discussed.

  6. Phenomenology of unified gauge theories

    International Nuclear Information System (INIS)

    Ellis, J.

    1983-01-01

    Part I of these lectures treats the standard Glashow-Weinberg-Salam model of weak and electromagnetic interactions, discussing in turn its basic structure and weak neutral currents, charged currents, mixing angles and CP violation, and the phenomenology of weak vector and Higgs bosons. Part II of the lectures discusses the structure of theories of dynamical symmetry breaking such as technicolour, phenomenological consequences, frustrations and alternatives. The third part of these lectures offers the standard menu of grand unified theories (GUTs) of the strong, weak and electromagnetic interactions, including an hors d'oeuvre of constraints on the parameters of the standard model, a main course of baryon number violating processes, and desserts which violate lepton number and CP. The fourth and final part goes through different attempts to remedy the inadequacies of previous theories by invoking supersymmetry and reaching out towards gravitation. (orig./HSI)

  7. Unified theory in the worldline approach

    Directory of Open Access Journals (Sweden)

    James P. Edwards

    2015-11-01

    Full Text Available We explore unified field theories based on the gauge groups SU(5 and SO(10 using the worldline approach for chiral fermions with a Wilson loop coupling to a background gauge field. Representing path ordering and chiral projection operators with functional integrals has previously reproduced the sum over the chiralities and representations of standard model particles in a compact way. This paper shows that for SU(5 the 5¯ and 10 representations – into which the Georgi–Glashow model places the left-handed fermionic content of the standard model – appear naturally and with the familiar chirality. We carry out the same analysis for flipped SU(5 and uncover a link to SO(10 unified theory. We pursue this by exploring the SO(10 theory in the same framework, the less established unified theory based on SU(6 and briefly consider the Pati–Salam model using SU(4×SU(2×SU(2.

  8. Warm Absorber Diagnostics of AGN Dynamics

    Science.gov (United States)

    Kallman, Timothy

    Warm absorbers and related phenomena are observable manifestations of outflows or winds from active galactic nuclei (AGN) that have great potential value. Understanding AGN outflows is important for explaining the mass budgets of the central accreting black hole, and also for understanding feedback and the apparent co-evolution of black holes and their host galaxies. In the X-ray band warm absorbers are observed as photoelectric absorption and resonance line scattering features in the 0.5-10 keV energy band; the UV band also shows resonance line absorption. Warm absorbers are common in low luminosity AGN and they have been extensively studied observationally. They may play an important role in AGN feedback, regulating the net accretion onto the black hole and providing mechanical energy to the surroundings. However, fundamental properties of the warm absorbers are not known: What is the mechanism which drives the outflow?; what is the gas density in the flow and the geometrical distribution of the outflow?; what is the explanation for the apparent relation between warm absorbers and the surprising quasi-relativistic 'ultrafast outflows' (UFOs)? We propose a focused set of model calculations that are aimed at synthesizing observable properties of warm absorber flows and associated quantities. These will be used to explore various scenarios for warm absorber dynamics in order to answer the questions in the previous paragraph. The guiding principle will be to examine as wide a range as possible of warm absorber driving mechanisms, geometry and other properties, but with as careful consideration as possible to physical consistency. We will build on our previous work, which was a systematic campaign for testing important class of scenarios for driving the outflows. We have developed a set of tools that are unique and well suited for dynamical calculations including radiation in this context. We also have state-of-the-art tools for generating synthetic spectra, which are

  9. A UV to mid-IR study of AGN selection

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Sun Mi; Kochanek, Christopher S. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Assef, Roberto [Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago (Chile); Brown, Michael J. I. [School of Physics, Monash University, Clayton, Vic 3800 (Australia); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Mail Stop 169-221, Pasadena, CA 91109 (United States); Jannuzi, Buell T. [Department of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Gonzalez, Anthony H. [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Hickox, Ryan C. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); Moustakas, John [Department of Physics and Astronomy, Siena College, 515 Loudon Road, Loudonville, NY 12211 (United States)

    2014-07-20

    We classify the spectral energy distributions (SEDs) of 431,038 sources in the 9 deg{sup 2} Boötes 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 (NEWFIRM), and mid-infrared (IRAC and MIPS) data, as well as spectroscopic redshifts for ∼20,000 objects, primarily from the AGN and Galaxy Evolution Survey. We fit galaxy, active galactic nucleus (AGN), stellar, and brown dwarf templates to the observed SEDs, which yield spectral classes for the Galactic sources and photometric redshifts and galaxy/AGN luminosities for the extragalactic sources. The photometric redshift precision of the galaxy and AGN samples are σ/(1 + z) = 0.040 and σ/(1 + z) = 0.169, respectively, with the worst 5% outliers excluded. On the basis of the χ{sub ν}{sup 2} of the SED fit for each SED model, we are able to distinguish between Galactic and extragalactic sources for sources brighter than I = 23.5 mag. We compare the SED fits for a galaxy-only model and a galaxy-AGN model. Using known X-ray and spectroscopic AGN samples, we confirm that SED fitting can be successfully used as a method to identify large populations of AGNs, including spatially resolved AGNs with significant contributions from the host galaxy and objects with the emission line ratios of 'composite' spectra. We also use our results to compare with the X-ray, mid-IR, optical color, and emission line ratio selection techniques. For an F-ratio threshold of F > 10, we find 16,266 AGN candidates brighter than I = 23.5 mag and a surface density of ∼1900 AGN deg{sup –2}.

  10. CERN Library | Agnes Chavez @ CERN | 17 March

    CERN Multimedia

    2015-01-01

    Agnes Chavez will present her work on Tuesday, 17 March 2015 at 4 p.m. in the Library (Builidng. 52-1-052) Coffee will be served from 3.30 p.m.   Agnes Chavez is an artist and educator participating in a two-week research stay organised by the ATLAS Experiment at CERN. Chavez is using the stay to develop her art and education project, Projecting pARTicles, which will be exploring particle physics through projection art. Chavez experiments with data visualization, sound and projection art to create participatory environments. She collaborates with programmers to create algorithmic drawings projected on to buildings, walls and spaces. This work explores our relationship with nature and technology, and how these and other sensory experiences determine how we perceive and interpret the world around us. For the Projecting pARTicles series she has formed an interdisciplinary team of programmers, artists, scientists and educators to investigate how we can create art and education interventions inspire...

  11. A unified theory in higher dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Kapetanakis, D. (National Research Centre for the Physical Sciences Democritos, Athens (Greece)); Zoupanos, G. (European Organization for Nuclear Research, Geneva (Switzerland))

    1990-10-11

    We present a grand unified model defined in ten dimensions and based on the group SO(13). The model is dimensionally reduced over the non-simply-connected space (Su(3)/U(1)xU(1))/Z{sub 2} giving in four dimensions the standard model. (orig.).

  12. A unified theory in higher dimensions

    International Nuclear Information System (INIS)

    Kapetanakis, D.; Zoupanos, G.

    1990-01-01

    We present a grand unified model defined in ten dimensions and based on the group SO(13). The model is dimensionally reduced over the non-simply-connected space [Su(3)/U(1)xU(1)]/Z 2 giving in four dimensions the standard model. (orig.)

  13. Grand unified theories

    International Nuclear Information System (INIS)

    Rosner, J.L.

    1987-01-01

    This paper reports on a pedagogical introduction that attempts to unify the strong and electroweak interactions. Unifying groups discussed include SU(5), SO(10), and E 6 . Particular attention is paid to the questions of whether the low-energy gauge group (that accessible at accelerator experiments in the foreseeable future) extends beyond SU(3) x SU(2) L x U(1). Low-energy studies of neutral-current effects, direct production of gauge bosons, and new fermions all can shed light on this question. Brief remarks are made concerning the role of monopoles, cosmic strings, baryogenesis, supersymmetry, and higher dimensions in this program

  14. Cromatografia unificada Unified chromatography

    Directory of Open Access Journals (Sweden)

    Carin von Mühlen

    2004-10-01

    Full Text Available The scope of this study encompasses an overview of the principles of unified chromatography as well as the principles of chromatographic techniques as applied to unified systems, which include gas chromatography, liquid chromatography, supercritical fluid chromatography, high temperature and high pressure liquid chromatography, micro-liquid chromatography, enhanced fluidity chromatography, and solvating gas chromatography. Theoretical considerations and individual instrumental parameters such as mobile phase, sample introduction system, columns, and detection system are also discussed. Future applications of this separation approach are discussed.

  15. Density profile of dark matter haloes and galaxies in the HORIZON-AGN simulation: the impact of AGN feedback

    Science.gov (United States)

    Peirani, Sébastien; Dubois, Yohan; Volonteri, Marta; Devriendt, Julien; Bundy, Kevin; Silk, Joe; Pichon, Christophe; Kaviraj, Sugata; Gavazzi, Raphaël; Habouzit, Mélanie

    2017-12-01

    Using a suite of three large cosmological hydrodynamical simulations, HORIZON-AGN, HORIZON–NOAGN (no AGN feedback) and HORIZON-DM (no baryons), we investigate how a typical sub-grid model for AGN feedback affects the evolution of the inner density profiles of massive dark matter haloes and galaxies. Based on direct object-to-object comparisons, we find that the integrated inner mass and density slope differences between objects formed in these three simulations (hereafter, HAGN, HnoAGN and HDM) significantly evolve with time. More specifically, at high redshift (z ∼ 5), the mean central density profiles of HAGN and HnoAGN dark matter haloes tend to be much steeper than their HDM counterparts owing to the rapidly growing baryonic component and ensuing adiabatic contraction. By z ∼ 1.5, these mean halo density profiles in HAGN have flattened, pummelled by powerful AGN activity ('quasar mode'): the integrated inner mass difference gaps with HnoAGN haloes have widened, and those with HDM haloes have narrowed. Fast forward 9.5 billion years, down to z = 0, and the trend reverses: HAGN halo mean density profiles drift back to a more cusped shape as AGN feedback efficiency dwindles ('radio mode'), and the gaps in integrated central mass difference with HnoAGN and HDM close and broaden, respectively. On the galaxy side, the story differs noticeably. Averaged stellar profile central densities and inner slopes are monotonically reduced by AGN activity as a function of cosmic time, resulting in better agreement with local observations.

  16. Standard(-like) Model from an SO(12) Grand Unified Theory in six-dimensions with S2 extra-space

    International Nuclear Information System (INIS)

    Nomura, Takaaki; Sato, Joe

    2009-01-01

    We analyze a gauge-Higgs unification model which is based on a gauge theory defined on a six-dimensional spacetime with an S 2 extra-space. We impose a symmetry condition for a gauge field and non-trivial boundary conditions of the S 2 . We provide the scheme for constructing a four-dimensional theory from the six-dimensional gauge theory under these conditions. We then construct a concrete model based on an SO(12) gauge theory with fermions which lie in a 32 representation of SO(12), under the scheme. This model leads to a Standard Model(-like) gauge theory which has gauge symmetry SU(3)xSU(2) L xU(1) Y (xU(1) 2 ) and one generation of SM fermions, in four-dimensions. The Higgs sector of the model is also analyzed, and it is shown that the electroweak symmetry breaking and the prediction of W-boson and Higgs-boson masses are obtained

  17. Environment Study of AGNs at z = 0.3 to 3.0 Using the Japanese Virtual Observatory

    Science.gov (United States)

    Shirasaki, Y.; Ohishi, M.; Mizumoto, Y.; Takata, T.; Tanaka, M.; Yasuda, N.

    2010-12-01

    We present a science use case of Virtual Observatory, which was achieved to examine an environment of AGN up to redshift of 3.0. We used the Japanese Virtual Observatory (JVO) to obtain Subaru Suprime-Cam images around known AGNs. According to the hierarchical galaxy formation model, AGNs are expected to be found in an environment of higher galaxy density than that of typical galaxies. The current observations, however, indicate that AGNs do not reside in a particularly high density environment. We investigated ˜1000 AGNs, which is about ten times larger samples than the other studies covering the redshifts larger than 0.6. We successfully found significant excess of galaxies around AGNs at redshifts of 0.3 to 1.8. If this work was done in a classical manner, that is, raw data were retrieved from the archive through a form-based web interface in an interactive way, and the data were reduced on a low performance computer, it might take several years to finish it. Since the Virtual Observatory system is accessible through a standard interface, it is easy to query and retrieve data in an automatic way. We constructed a pipeline for retrieving the data and calculating the galaxy number density around a given coordinate. This procedure was executed in parallel on ˜10 quad core PCs, and it took only one day for obtaining the final result. Our result implies that the Virtual Observatory can be a powerful tool to do an astronomical research based on large amount of data.

  18. Prospects of a Unified Management System

    DEFF Research Database (Denmark)

    Jørgensen, Tine Herreborg; Simonsen, Gorm

    2002-01-01

    In this article, the trend among management systems towards a common structure and the inclusion of additional areas of corporate concern (quality, environment, occupational health and safety and social responsibility) is outlined. The article suggests that a large part of the work associated...... with implementing and maintaining standardised management systems can be rationalised by developing a ?unified system?. The unified system is proposed to consist of a common basic standard of general managerial methodology expandable with supplements, which are related to the specific areas of concern...

  19. AGN outflows as neutrino sources: an observational test

    Science.gov (United States)

    Padovani, P.; Turcati, A.; Resconi, E.

    2018-04-01

    We test the recently proposed idea that outflows associated with Active Galactic Nuclei (AGN) could be neutrino emitters in two complementary ways. First, we cross-correlate a list of 94 "bona fide" AGN outflows with the most complete and updated repository of IceCube neutrinos currently publicly available, assembled by us for this purpose. It turns out that AGN with outflows matched to an IceCube neutrino have outflow and kinetic energy rates, and bolometric powers larger than those of AGN with outflows not matched to neutrinos. Second, we carry out a statistical analysis on a catalogue of [O III] λ5007 line profiles using a sample of 23,264 AGN at z values (˜6 and 18 per cent respectively, pre-trial) for relatively high velocities and luminosities. Our results are consistent with a scenario where AGN outflows are neutrino emitters but at present do not provide a significant signal. This can be tested with better statistics and source stacking. A predominant role of AGN outflows in explaining the IceCube data appears in any case to be ruled out.

  20. Unified electricity market

    International Nuclear Information System (INIS)

    Anon

    2011-01-01

    A unified European electricity market means a unification and harmonisation of functioning of the national electricity market into one European Market or into one entity. It gives an opportunity to Slovenske elektrarne to open room for their wider activity within Europe where common rules for cross-boarder trade and markets functioning will apply. (author)

  1. Unified field theory

    International Nuclear Information System (INIS)

    Prasad, R.

    1975-01-01

    Results of researches into Unified Field Theory over the past seven years are presented. The subject is dealt with in chapters entitled: the choice of affine connection, algebraic properties of the vector fields, field laws obtained from the affine connection based on the path integral method, application to quantum theory and cosmology, interpretation of physical theory in terms of geometry. (U.K.)

  2. Finite unified models

    Energy Technology Data Exchange (ETDEWEB)

    Kapetanakis, D. (Technische Univ. Muenchen, Garching (Germany). Physik Dept.); Mondragon, M. (Technische Univ. Muenchen, Garching (Germany). Physik Dept.); Zoupanos, G. (National Technical Univ., Athens (Greece). Physics Dept.)

    1993-09-01

    We present phenomenologically viable SU(5) unified models which are finite to all orders before the spontaneous symmetry breaking. In the case of two models with three families the top quark mass is predicted to be 178.8 GeV. (orig.)

  3. Finite unified models

    International Nuclear Information System (INIS)

    Kapetanakis, D.; Mondragon, M.; Zoupanos, G.

    1993-01-01

    We present phenomenologically viable SU(5) unified models which are finite to all orders before the spontaneous symmetry breaking. In the case of two models with three families the top quark mass is predicted to be 178.8 GeV. (orig.)

  4. Imaging AGN Feedback in NGC 3393 with CHEERS

    Science.gov (United States)

    Paggi, Alessandro; Maksym, W. Peter; Fabbiano, Giuseppina; Elvis, Martin; Karovska, Margarita; Wang, Junfeng; Storchi-Bergmann, Thaisa

    2016-04-01

    The CHandra Extended Emission-line Region Survey (CHEERS) is the 'ultimate' resolution X-ray imaging survey of nearby far-IR selected AGN. By comparing deep Chandra observations with complementary HST and radio data, we investigate the morphology of the extended narrow-line region on scales of <100 pc. We present new results on the gas surrounding the compton-thick AGN NGC 3393. The luminous extended narrow-line X-ray emission from this gas allows us to study the role and extent of AGN feedback as sub-kpc jets interact with the surrounding ISM.

  5. The Unified Theory of Physics

    OpenAIRE

    Chung, Ding-Yu

    2002-01-01

    The unified theory of physics unifies various phenomena in our observable universe and other universes. The unified theory is based on the zero-energy universe and the space-object structures. Different universes in different developmental stages are the different expressions of the space-object structures. The unified theory is divided into five parts: the space-object structures, cosmology, the periodic table of elementary particles, the galaxy formation, and the extreme force field. The sp...

  6. Automated spectral and timing analysis of AGNs

    Science.gov (United States)

    Munz, F.; Karas, V.; Guainazzi, M.

    2006-12-01

    % We have developed an autonomous script that helps the user to automate the XMM-Newton data analysis for the purposes of extensive statistical investigations. We test this approach by examining X-ray spectra of bright AGNs pre-selected from the public database. The event lists extracted in this process were studied further by constructing their energy-resolved Fourier power-spectrum density. This analysis combines energy distributions, light-curves, and their power-spectra and it proves useful to assess the variability patterns present is the data. As another example, an automated search was based on the XSPEC package to reveal the emission features in 2-8 keV range.

  7. Long term multiwavelength studies of the corona/disc connection in AGN

    Science.gov (United States)

    Buisson, D.; Lohfink, A.; Alston, W.; Fabian, A.; Gallo, L.; Kara, E.; Zoghbi, A.; Wilkins, D.; Miller, J.; Cackett, E.

    2017-10-01

    One way of increasing our understanding of AGN is determining the nature of the connection between the optical/UV emitting accretion disc and the X-ray emitting corona. Studies of variability in these two bands are a key tool for gaining insight into the processes involved. We will present results from a sample of long-term AGN monitoring campaigns in the optical, UV and X-ray with Swift. In particular, we will explore UV/optical-X-ray correlations and associated time lags. We will compare these measurements and the UV/optical RMS spectra with theoretical reprocessing models and confront recent claims of the observed lags being longer than those which are expected for a standard thin disc. Additionally, a new Swift monitoring campaign of the z=2 quasar PG 1247+267 allows us to probe the shorter wavelengths at the peak of the accretion disc spectrum, providing information on the region of the disc closest to the black hole. However, not all AGN show such correlations, including IRAS 13224-3809, the subject of a recent 1.5 Ms XMM observation. Using this and other examples, we will explore the possible reasons for the lack of observed correlation.

  8. Evolutionary behaviour of AGN: Investigations on BL Lac objects and Seyfert II galaxies

    Science.gov (United States)

    Beckmann, V.

    2000-12-01

    The evolution and nature of AGN is still one of the enigmatic questions in astrophysics. While large and complete Quasar samples are available, special classes of AGN, like BL Lac objects and Seyfert II galaxies, are still rare objects. In this work I present two new AGN samples. The first one is the HRX-BL Lac survey, resulting in a sample of X-ray selected BL Lac objects. This sample results from 223 BL Lac candidates based on a correlation of X-ray sources with radio sources. The identification of this sample is 98% complete. 77 objects have been identified as BL Lac objects and form the HRX-BL Lac complete sample, the largest homogeneous sample of BL Lac objects existing today. For this sample, redshifts are now known for 62 objects (81 %). In total I present 101 BL Lac objects in the enlarged HRX-BL Lac survey, for which redshift information is available for 84 objects. During the HRX-BL Lac survey I found several objects of special interest. 1ES 1517+656 turned out to be the brightest known BL Lac object in the universe. 1ES 0927+500 could be the first BL Lac object with a line detected in the X-ray region. RX J1211+2242 is probably the the counterpart of the up to now unidentified gamma-ray source 3EG J1212+2304. Additionally I present seven candidates for ultra high frequency peaked BL Lac objects. RX J1054+3855 and RX J1153+3517 are rare high redshift X-ray bright QSO or accreting binary systems with huge magnetic fields. For the BL Lac objects I suggest an unified scenario in which giant elliptical galaxies, formed by merging events of spiral galaxies at z > 2, start as powerful, radio dominated BL Lacs. As the jet gets less powerful, the BL Lacs start to get more X-ray dominated, showing less total luminosities (for z definition to objects with a calcium break up to 40%, but do not support for the HBL the idea of allowing emission lines in the spectra of BL Lac galaxies. A way to find high redshift BL Lac objects might be the identification of faint X

  9. High spectral resolution X-ray observations of AGN

    NARCIS (Netherlands)

    Kaastra, J.S.

    2008-01-01

    brief overview of some highlights of high spectral resolution X-ray observations of AGN is given, mainly obtained with the RGS of XMM-Newton. Future prospects for such observations with XMM-Newton are given.

  10. FROM NEARBY LOW LUMINOSITY AGN TO HIGH REDSHIFT ...

    Indian Academy of Sciences (India)

    44

    6Amity Institute of Applied Sciences, Amity University Uttar Pradesh, Sector 125, Noida ... We present detailed science cases that a large fraction of the Indian AGN ..... kiloparsec-scale radio study of the MOJAVE6 blazar sample. Kharb et al.

  11. Can double-peaked lines indicate merging effects in AGNs?

    Directory of Open Access Journals (Sweden)

    Popović L.Č.

    2000-01-01

    Full Text Available The influence of merging effects in the central part of an Active Galactic Nucleus (AGN on the emission spectral line shapes are discussed. We present a model of close binary Broad Line Region. The numerical experiments show that the merging effects can explain double peaked lines. The merging effects may also be present in the center of AGNs, although they emit slightly asymmetric as well as symmetric and relatively stable (in profile shape spectral lines. Depending on the black hole masses and their orbit elements such model may explain some of the line profile shapes observed in AGNs. This work shows that if one is looking for the merging effects in the central region as well as in the wide field structure of AGNs, he should first pay attention to objects which have double peaked lines.

  12. Can the laws of physics be unified ?

    CERN Document Server

    Langacker, Paul

    2017-01-01

    The standard model of particle physics describes our current understanding of nature's fundamental particles and their interactions, yet gaps remain. For example, it does not include a quantum theory of gravity, nor does it explain the existence of dark matter. Once complete, however, the standard model could provide a unified description of the very building blocks of the universe. Researchers have been chasing this dream for decades, and many wonder whether such a dream can ever be made a reality. Can the Laws of Physics Be Unified? is a short introduction to this exciting frontier of physics. The book is accessibly written for students and researchers across the sciences, and for scientifically minded general readers. Paul Langacker begins with an overview of the key breakthroughs that have shaped the standard model, and then describes the fundamental particles, their interactions, and their role in cosmology. He goes on to explain field theory, internal symmetries, Yang-Mills theories, strong and electro...

  13. A unified universe

    DEFF Research Database (Denmark)

    Codello, Alessandro; Jain, Rajeev Kumar

    2018-01-01

    We present a unified evolution of the universe from very early times until the present epoch by including both the leading local correction R2 and the leading non-local term R1□2R to the classical gravitational action. We find that the inflationary phase driven by R2 term gracefully exits...... in a transitory regime characterized by coherent oscillations of the Hubble parameter. The universe then naturally enters into a radiation dominated epoch followed by a matter dominated era. At sufficiently late times after radiation–matter equality, the non-local term starts to dominate inducing an accelerated...... expansion of the universe at the present epoch. We further exhibit the fact that both the leading local and non-local terms can be obtained within the covariant effective field theory of gravity. This scenario thus provides a unified picture of inflation and dark energy in a single framework by means...

  14. Development of AGNES, a kinetics code for fissile solutions, 1

    International Nuclear Information System (INIS)

    Nakajima, Ken; Ohnishi, Nobuaki

    1986-01-01

    A kinetics code for fissile solutions, AGNES (Accidentally Generated Nuclear Excursion Simulation code), has been developed. This code calculates the radiolytic gas void effect as a reactivity feedback. Physical and calculative models of the radiolytic gas void are summarized and the usage of AGNES is described. In addition, some benchmark calculations were performed and results of calculations show good agreement with those of experiments. (author)

  15. Operation Unified Protector

    DEFF Research Database (Denmark)

    Buhl, Kenneth Øhlenschlæger

    2012-01-01

    Formålet med denne artikel er at se nærmere på erfaringerne fra den maritime kampagne under den militære indsats i konflikten i Libyen i 2011, som i NATO regi blev kendt som Operation Unified Protector (OUP). Dækningen i de danske medier fokuserede primært på luftkampagnen, hvilket må tilskrives,...

  16. Unified Engineering Software System

    Science.gov (United States)

    Purves, L. R.; Gordon, S.; Peltzman, A.; Dube, M.

    1989-01-01

    Collection of computer programs performs diverse functions in prototype engineering. NEXUS, NASA Engineering Extendible Unified Software system, is research set of computer programs designed to support full sequence of activities encountered in NASA engineering projects. Sequence spans preliminary design, design analysis, detailed design, manufacturing, assembly, and testing. Primarily addresses process of prototype engineering, task of getting single or small number of copies of product to work. Written in FORTRAN 77 and PROLOG.

  17. Rational Unified Process

    OpenAIRE

    Kopal, Nils

    2016-01-01

    In this German seminar paper, which was written in the year 2011 at the University of Duisburg for a Bachelor Colloquium in Applied computer science, we show a brief overview of the Rational Unified Process (RUP). Thus, interested students or generally interested people in software development gain a first impression of RUP. The paper includes a survey and overview of the underlying process structure, the phases of the process, its workflows, and describes the always by the RUP developers pos...

  18. Testing AGN unification via inference from large catalogs

    Science.gov (United States)

    Nikutta, Robert; Ivezic, Zeljko; Elitzur, Moshe; Nenkova, Maia

    2018-01-01

    Source orientation and clumpiness of the central dust are the main factors in AGN classification. Type-1 QSOs are easy to observe and large samples are available (e.g. in SDSS), but obscured type-2 AGN are dimmer and redder as our line of sight is more obscured, making it difficult to obtain a complete sample. WISE has found up to a million QSOs. With only 4 bands and a relatively small aperture the analysis of individual sources is challenging, but the large sample allows inference of bulk properties at a very significant level.CLUMPY (www.clumpy.org) is arguably the most popular database of AGN torus SEDs. We model the ensemble properties of the entire WISE AGN content using regularized linear regression, with orientation-dependent CLUMPY color-color-magnitude (CCM) tracks as basis functions. We can reproduce the observed number counts per CCM bin with percent-level accuracy, and simultaneously infer the probability distributions of all torus parameters, redshifts, additional SED components, and identify type-1/2 AGN populations through their IR properties alone. We increase the statistical power of our AGN unification tests even further, by adding other datasets as axes in the regression problem. To this end, we make use of the NOAO Data Lab (datalab.noao.edu), which hosts several high-level large datasets and provides very powerful tools for handling large data, e.g. cross-matched catalogs, fast remote queries, etc.

  19. A model for AGN variability on multiple time-scales

    Science.gov (United States)

    Sartori, Lia F.; Schawinski, Kevin; Trakhtenbrot, Benny; Caplar, Neven; Treister, Ezequiel; Koss, Michael J.; Urry, C. Megan; Zhang, C. E.

    2018-05-01

    We present a framework to link and describe active galactic nuclei (AGN) variability on a wide range of time-scales, from days to billions of years. In particular, we concentrate on the AGN variability features related to changes in black hole fuelling and accretion rate. In our framework, the variability features observed in different AGN at different time-scales may be explained as realisations of the same underlying statistical properties. In this context, we propose a model to simulate the evolution of AGN light curves with time based on the probability density function (PDF) and power spectral density (PSD) of the Eddington ratio (L/LEdd) distribution. Motivated by general galaxy population properties, we propose that the PDF may be inspired by the L/LEdd distribution function (ERDF), and that a single (or limited number of) ERDF+PSD set may explain all observed variability features. After outlining the framework and the model, we compile a set of variability measurements in terms of structure function (SF) and magnitude difference. We then combine the variability measurements on a SF plot ranging from days to Gyr. The proposed framework enables constraints on the underlying PSD and the ability to link AGN variability on different time-scales, therefore providing new insights into AGN variability and black hole growth phenomena.

  20. The Swift/BAT AGN Spectroscopic Survey. IX. The Clustering Environments of an Unbiased Sample of Local AGNs

    Science.gov (United States)

    Powell, M. C.; Cappelluti, N.; Urry, C. M.; Koss, M.; Finoguenov, A.; Ricci, C.; Trakhtenbrot, B.; Allevato, V.; Ajello, M.; Oh, K.; Schawinski, K.; Secrest, N.

    2018-05-01

    We characterize the environments of local accreting supermassive black holes by measuring the clustering of AGNs in the Swift/BAT Spectroscopic Survey (BASS). With 548 AGN in the redshift range 0.01 2MASS galaxies, and interpreting it via halo occupation distribution and subhalo-based models, we constrain the occupation statistics of the full sample, as well as in bins of absorbing column density and black hole mass. We find that AGNs tend to reside in galaxy group environments, in agreement with previous studies of AGNs throughout a large range of luminosity and redshift, and that on average they occupy their dark matter halos similar to inactive galaxies of comparable stellar mass. We also find evidence that obscured AGNs tend to reside in denser environments than unobscured AGNs, even when samples were matched in luminosity, redshift, stellar mass, and Eddington ratio. We show that this can be explained either by significantly different halo occupation distributions or statistically different host halo assembly histories. Lastly, we see that massive black holes are slightly more likely to reside in central galaxies than black holes of smaller mass.

  1. On the Intermediate Line Region in AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Adhikari, Tek P.; Różańska, Agata; Hryniewicz, Krzysztof [Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, Warsaw (Poland); Czerny, Bozena [Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, Warsaw (Poland); Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland); Ferland, Gary J., E-mail: tek@camk.edu.pl [Department of Physics and Astronomy, The University of Kentucky, Lexington, KY (United States)

    2017-09-29

    In this paper we explore the intermediate line region (ILR) by using the photoionisation simulations of the gas clouds present at different radial distances from the center, corresponding to the locations from BLR out to NLR in four types of AGNs. We let for the presence of dust whenever conditions allow for dust existence. All spectral shapes are taken from the recent multi-wavelength campaigns. The cloud density decreases with distance as a power law. We found that the slope of the power law density profile does not affect the line emissivity radial profiles of major emission lines: Hβ, He II, Mg II, C III, and O III. When the density of the cloud at the sublimation radius is as high as 10{sup 11.5} cm{sup −3}, the ILR should clearly be seen in the observations independently of the shape of the illuminating radiation. Moreover, our result is valid for low ionization nuclear emission regions of active galaxies.

  2. Unified Symmetry of Hamilton Systems

    International Nuclear Information System (INIS)

    Xu Xuejun; Qin Maochang; Mei Fengxiang

    2005-01-01

    The definition and the criterion of a unified symmetry for a Hamilton system are presented. The sufficient condition under which the Noether symmetry is a unified symmetry for the system is given. A new conserved quantity, as well as the Noether conserved quantity and the Hojman conserved quantity, deduced from the unified symmetry, is obtained. An example is finally given to illustrate the application of the results.

  3. Unified Bohm criterion

    Energy Technology Data Exchange (ETDEWEB)

    Kos, L. [LECAD Laboratory, Faculty of Mechanical Engineering, University of Ljubljana, SI-1000 Ljubljana (Slovenia); Tskhakaya, D. D.; Jelić, N. [Institute for Theoretical Physics, Fusion@ÖAW, University of Innsbruck, A-6020 Innsbruck (Austria)

    2015-09-15

    Recent decades have seen research into the conditions necessary for the formation of the monotonic potential shape in the sheath, appearing at the plasma boundaries like walls, in fluid, and kinetic approximations separately. Although either of these approaches yields a formulation commonly known as the much-acclaimed Bohm criterion (BC), the respective results involve essentially different physical quantities that describe the ion gas behavior. In the fluid approach, such a quantity is clearly identified as the ion directional velocity. In the kinetic approach, the ion behavior is formulated via a quantity (the squared inverse velocity averaged by the ion distribution function) without any clear physical significance, which is, moreover, impractical. In the present paper, we try to explain this difference by deriving a condition called here the Unified Bohm Criterion, which combines an advanced fluid model with an upgraded explicit kinetic formula in a new form of the BC. By introducing a generalized polytropic coefficient function, the unified BC can be interpreted in a form that holds, irrespective of whether the ions are described kinetically or in the fluid approximation.

  4. Beyond the Unified Model

    Science.gov (United States)

    Frauendorf, S.

    2018-04-01

    The key elements of the Unified Model are reviewed. The microscopic derivation of the Bohr Hamiltonian by means of adiabatic time-dependent mean field theory is presented. By checking against experimental data the limitations of the Unified Model are delineated. The description of the strong coupling between the rotational and intrinsic degrees of freedom in framework of the rotating mean field is presented from a conceptual point of view. The classification of rotational bands as configurations of rotating quasiparticles is introduced. The occurrence of uniform rotation about an axis that differs from the principle axes of the nuclear density distribution is discussed. The physics behind this tilted-axis rotation, unknown in molecular physics, is explained on a basic level. The new symmetries of the rotating mean field that arise from the various orientations of the angular momentum vector with respect to the triaxial nuclear density distribution and their manifestation by the level sequence of rotational bands are discussed. Resulting phenomena, as transverse wobbling, rotational chirality, magnetic rotation and band termination are discussed. Using the concept of spontaneous symmetry breaking the microscopic underpinning of the rotational degrees is refined.

  5. CHARACTERIZATION OF A SAMPLE OF INTERMEDIATE-TYPE AGNs. I. SPECTROSCOPIC PROPERTIES AND SERENDIPITOUS DISCOVERY OF NEW DUAL AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Benitez, Erika; Cruz-Gonzalez, Irene; Martinez, Benoni; Jimenez-Bailon, Elena [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Apdo. Postal 70-264, Mexico D.F. 04510 (Mexico); Mendez-Abreu, Jairo; Lopez-Martin, Luis [Instituto de Astrofisica de Canarias, E-38200 La Laguna, Tenerife (Spain); Fuentes-Carrera, Isaura [Escuela Superior de Fisica y Matematicas, Instituto Politecnico Nacional (ESFM-IPN), U.P. Adolfo Lopez Mateos, Mexico D.F. 07730 (Mexico); Leon-Tavares, Jonathan [Aalto University Metsaehovi Radio Observatory, Metsaehovintie 114, FI-02540, Kylmaelae (Finland); Chavushyan, Vahram H., E-mail: erika@astro.unam.mx [Instituto Nacional de Astrofisica, Optica y Electronica, Apdo. Postal 51-216, 72000 Puebla (Mexico)

    2013-01-20

    A sample of 10 nearby intermediate-type active galactic nuclei (AGNs) drawn from the Sloan Digital Sky Survey is presented. The aim of this work is to provide estimations of the black hole (BH) mass for the sample galaxies from the dynamics of the broad-line region. For this purpose, a detailed spectroscopic analysis of the objects was done. Using Baldwin-Phillips-Terlevich diagnostic diagrams, we have carefully classified the objects as true intermediate-type AGNs and found that 80%{sup +7.2%} {sub -17.3%} are composite AGNs. The BH mass estimated for the sample is within 6.54 {+-} 0.16 < log M {sub BH} < 7.81 {+-} 0.14. Profile analysis shows that five objects (J120655.63+501737.1, J121607.08+504930.0, J141238.14+391836.5, J143031.18+524225.8, and J162952.88+242638.3) have narrow double-peaked emission lines in both the red (H{alpha}, [N II] {lambda}{lambda}6548,6583 and [S II] {lambda}{lambda}6716, 6731) and the blue (H{beta} and [O III] {lambda}{lambda}4959, 5007) regions of the spectra, with velocity differences ({Delta}V) between the double peaks within 114 km s{sup -1} < {Delta}V < 256 km s{sup -1}. Two of them, J121607.08+504930.0 and J141238.14+391836.5, are candidates for dual AGNs since their double-peaked emission lines are dominated by AGN activity. In searches of dual AGNs, type 1, type II, and intermediate-type AGNs should be carefully separated, due to the high serendipitous number of narrow double-peaked sources (50% {+-} 14.4%) found in our sample.

  6. Average Heating Rate of Hot Atmospheres in Distant Galaxy Clusters by Radio AGN: Evidence for Continuous AGN Heating

    Science.gov (United States)

    Ma, Cheng-Jiun; McNamara, B.; Nulsen, P.; Schaffer, R.

    2011-09-01

    X-ray observations of nearby clusters and galaxies have shown that energetic feedback from AGN is heating hot atmospheres and is probably the principal agent that is offsetting cooling flows. Here we examine AGN heating in distant X-ray clusters by cross correlating clusters selected from the 400 Square Degree X-ray Cluster survey with radio sources in the NRAO VLA Sky Survey. The jet power for each radio source was determined using scaling relations between radio power and cavity power determined for nearby clusters, groups, and galaxies with atmospheres containing X-ray cavities. Roughly 30% of the clusters show radio emission above a flux threshold of 3 mJy within the central 250 kpc that is presumably associated with the brightest cluster galaxy. We find no significant correlation between radio power, hence jet power, and the X-ray luminosities of clusters in redshift range 0.1 -- 0.6. The detection frequency of radio AGN is inconsistent with the presence of strong cooling flows in 400SD, but cannot rule out the presence of weak cooling flows. The average jet power of central radio AGN is approximately 2 10^{44} erg/s. The jet power corresponds to an average heating of approximately 0.2 keV/particle for gas within R_500. Assuming the current AGN heating rate remained constant out to redshifts of about 2, these figures would rise by a factor of two. Our results show that the integrated energy injected from radio AGN outbursts in clusters is statistically significant compared to the excess entropy in hot atmospheres that is required for the breaking of self-similarity in cluster scaling relations. It is not clear that central AGN in 400SD clusters are maintained by a self-regulated feedback loop at the base of a cooling flow. However, they may play a significant role in preventing the development of strong cooling flows at early epochs.

  7. The energetics of AGN radiation pressure-driven outflows

    Science.gov (United States)

    Ishibashi, W.; Fabian, A. C.; Maiolino, R.

    2018-05-01

    The increasing observational evidence of galactic outflows is considered as a sign of active galactic nucleus (AGN) feedback in action. However, the physical mechanism responsible for driving the observed outflows remains unclear, and whether it is due to momentum, energy, or radiation is still a matter of debate. The observed outflow energetics, in particular the large measured values of the momentum ratio (\\dot{p}/(L/c) ˜ 10) and energy ratio (\\dot{E}_k/L ˜ 0.05), seems to favour the energy-driving mechanism; and most observational works have focused their comparison with wind energy-driven models. Here, we show that AGN radiation pressure on dust can adequately reproduce the observed outflow energetics (mass outflow rate, momentum flux, and kinetic power), as well as the scalings with luminosity, provided that the effects of radiation trapping are properly taken into account. In particular, we predict a sublinear scaling for the mass outflow rate (\\dot{M} ∝ L^{1/2}) and a superlinear scaling for the kinetic power (\\dot{E}_k ∝ L^{3/2}), in agreement with the observational scaling relations reported in the most recent compilation of AGN outflow data. We conclude that AGN radiative feedback can account for the global outflow energetics, at least equally well as the wind energy-driving mechanism, and therefore both physical models should be considered in the interpretation of future AGN outflow observations.

  8. Revisiting the `forbidden' region: AGN radiative feedback with radiation trapping

    Science.gov (United States)

    Ishibashi, W.; Fabian, A. C.; Ricci, C.; Celotti, A.

    2018-06-01

    Active galactic nucleus (AGN) feedback, driven by radiation pressure on dust, is an important mechanism for efficiently coupling the accreting black hole to the surrounding environment. Recent observations confirm that X-ray selected AGN samples respect the effective Eddington limit for dusty gas in the plane defined by the observed column density versus the Eddington ratio, the so-called NH - λ plane. A `forbidden' region occurs in this plane, where obscuring clouds cannot be long-lived, due to the action of radiation pressure on dust. Here we compute the effective Eddington limit by explicitly taking into account the trapping of reprocessed radiation (which has been neglected in previous works), and investigate its impact on the NH - λ plane. We show that the inclusion of radiation trapping leads to an enhanced forbidden region, such that even Compton-thick material can potentially be disrupted by sub-Eddington luminosities. We compare our model results to the most complete sample of local AGNs with measured X-ray properties, and find good agreement. Considering the anisotropic emission from the accretion disc, we also expect the development of dusty outflows along the polar axis, which may naturally account for the polar dust emission recently detected in several AGNs from mid-infrared observations. Radiative feedback thus appears to be the key mechanism regulating the obscuration properties of AGNs, and we discuss its physical implications in the context of co-evolution scenarios.

  9. The joint fit of the BHMF and ERDF for the BAT AGN Sample

    Science.gov (United States)

    Weigel, Anna K.; Koss, Michael; Ricci, Claudio; Trakhtenbrot, Benny; Oh, Kyuseok; Schawinski, Kevin; Lamperti, Isabella

    2018-01-01

    A natural product of an AGN survey is the AGN luminosity function. This statistical measure describes the distribution of directly measurable AGN luminosities. Intrinsically, the shape of the luminosity function depends on the distribution of black hole masses and Eddington ratios. To constrain these fundamental AGN properties, the luminosity function thus has to be disentangled into the black hole mass and Eddington ratio distribution function. The BASS survey is unique as it allows such a joint fit for a large number of local AGN, is unbiased in terms of obscuration in the X-rays and provides black hole masses for type-1 and type-2 AGN. The black hole mass function at z ~ 0 represents an essential baseline for simulations and black hole growth models. The normalization of the Eddington ratio distribution function directly constrains the AGN fraction. Together, the BASS AGN luminosity, black hole mass and Eddington ratio distribution functions thus provide a complete picture of the local black hole population.

  10. GP-support by means of AGnES-practice assistants and the use of telecare devices in a sparsely populated region in Northern Germany – proof of concept

    Directory of Open Access Journals (Sweden)

    Scriba Sibylle

    2009-06-01

    Full Text Available Abstract Background In many rural regions in Germany, the proportion of the elderly population increases rapidly. Simultaneously, about one-third of the presently active GPs will retire until 2010. Often it is difficult to find successors for vacant GP-practices. These regions require innovative concepts to avoid the imminent shortage in primary health care. The AGnES-concept comprises the delegation of GP-home visits to qualified AGnES-practice assistants (AGnES: GP-supporting, community-based, e-health-assisted, systemic intervention. Main objectives were the assessment of the acceptance of the AGnES-concept by the participating GPs, patients, and AGnES-practice assistants, the kind of delegated tasks, and the feasibility of home telecare in a GP-practice. Methods In this paper, we report first results of the implementation of this concept in regular GP-practices, conducted November 2005 – March 2007 on the Island of Rügen, Mecklenburg-Western Pomerania, Germany. This study was meant as a proof of concept. The GP delegated routine home-visits to qualified practice employees (here: registered nurses. Eligible patients were provided with telecare-devices to monitor disease-related physiological values. All delegated tasks, modules conducted and questionnaire responses were documented. The participating patients were asked for their acceptance based on standardized questionnaires. The GPs and AGnES-practice assistants were asked for their judgement about different project components, the quality of health care provision and the competences of the AGnES-practice assistants. Results 550 home visits were conducted. 105 patients, two GPs and three AGnES-practice assistants (all registered nurses participated in the project. 48 patients used telecare-devices to monitor health parameters. 87.4% of the patients accepted AGnES-care as comparable to common GP-care. In the course of the project, the GPs delegated an increasing number of both monitoring

  11. Agnes Pockels: Life, Letters and Papers

    Science.gov (United States)

    Helm, Christiane A.

    2004-03-01

    Agnes Pockels (1862 - 1935) was a German woman, whose studies pioneered surface science. She was born in malaria infected North Italy while her father served in the Austrian army. Because he suffered adverse health effects, the family moved in1871 to Braunschweig (North Germany). There, Pockels went to high school. She was interested in science, but formal training was not available for girls. She took on the role of household manager and nurse as her parents' health deteriorated further. Her diary illustrates the difficulties she faced in trying to maintain her own health, the health of her parents and her scientific research at the same time. When Pockels was 18 or 19, she designed a ring tensiometer. Additionally, she found a new method to introduce water-insoluble compounds to the water surface by dissolving them in an organic solvent, and applying drops of the solution. Her surface film balance technique from 1882 is the basis for the method later developed by Langmuir. Since her experimental work was highly original and in a new field, she failed to get it recognized in her own country. When she was 28, she wrote to Lord Rayleigh, since she had read about his recent experiments in surface physics. Rayleigh was so impressed with her experimental methods and results that he had her letter translated from German and published it in Nature (1891). She continued her research on surface films, interactions of solutions and contact angles (more papers, 3 in Nature). Still, she did all experiments at home. With the death of her brother in 1913 and the onset of the war, she retired into private life. Thus she was surprised when she was awarded in her late 60ies with a honorary doctorate by the TU Braunschweig (1932) and the annual prize of the German Colloid Society (1931).

  12. High-Sensitivity AGN Polarimetry at Sub-Millimeter Wavelengths

    Directory of Open Access Journals (Sweden)

    Ivan Martí-Vidal

    2017-10-01

    Full Text Available The innermost regions of radio loud Active Galactic Nuclei (AGN jets are heavily affected by synchrotron self-absorption, due to the strong magnetic fields and high particle densities in these extreme zones. The only way to overcome this absorption is to observe at sub-millimeter wavelengths, although polarimetric observations at such frequencies have so far been limited by sensitivity and calibration accuracy. However, new generation instruments such as the Atacama Large mm/sub-mm Array (ALMA overcome these limitations and are starting to deliver revolutionary results in the observational studies of AGN polarimetry. Here we present an overview of our state-of-the-art interferometric mm/sub-mm polarization observations of AGN jets with ALMA (in particular, the gravitationally-lensed sources PKS 1830−211 and B0218+359, which allow us to probe the magneto-ionic conditions at the regions closest to the central black holes.

  13. Compton-thick AGN at high and low redshift

    Science.gov (United States)

    Akylas, A.; Georgantopoulos, I.; Corral, A.; Ranalli, P.; Lanzuisi, G.

    2017-10-01

    The most obscured sources detected in X-ray surveys, the Compton-thick AGN present great interest both because they represent the hidden side of accretion but also because they may signal the AGN birth. We analyse the NUSTAR observations from the serendipitous observations in order to study the Compton-thick AGN at the deepest possible ultra-hard band (>10 keV). We compare our results with our SWIFT/BAT findings in the local Universe, as well as with our results in the CDFS and COSMOS fields. We discuss the comparison with X-ray background synthesis models finding that a low fraction of Compton-thick sources (about 15 per cent of the obscured population) is compatible with both the 2-10keV band results and those at harder energies.

  14. Coeval Starburst and AGN Activity in the CDFS

    Science.gov (United States)

    Brusa, M.; Fiore, F.

    2009-10-01

    Here we present a study on the host galaxies properties of obscured Active Galactic Nuclei (AGN) detected in the CDFS 1Ms observation and for which deep K-band observations obtained with ISAAC@VLT are available. The aim of this study is to characterize the host galaxies properties of obscured AGN in terms of their stellar masses, star formation rates, and specific star formation rates. To this purpose we refined the X-ray/optical association of 179 1 Ms sources in the MUSIC area, using a three-bands (optical, K, and IRAC) catalog for the counterparts search and we derived the rest frame properties from SED fitting. We found that the host of obscured AGN at z>1 are associated with luminous, massive, red galaxies with significant star formation rates episodes still ongoing in about 50% of the sample.

  15. Mid-infrared Variability of Changing-look AGNs

    International Nuclear Information System (INIS)

    Sheng, Zhenfeng; Wang, Tinggui; Jiang, Ning; Yang, Chenwei; Peng, Bo; Yan, Lin; Dou, Liming

    2017-01-01

    It is known that some active galactic nuclei (AGNs) transit from Type 1 to Type 2 or vice versa. There are two explanations for the so-called changing-look AGNs: one is the dramatic change of the obscuration along the line of sight, and the other is the variation of accretion rate. In this Letter, we report the detection of large amplitude variations in the mid-infrared luminosity during the transitions in 10 changing-look AGNs using the Wide-field Infrared Survey Explorer ( WISE ) and newly released Near-Earth Object WISE Reactivation data. The mid-infrared light curves of 10 objects echo the variability in the optical band with a time lag expected for dust reprocessing. The large variability amplitude is inconsistent with the scenario of varying obscuration, rather it supports the scheme of dramatic change in the accretion rate.

  16. Mid-infrared Variability of Changing-look AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, Zhenfeng; Wang, Tinggui; Jiang, Ning; Yang, Chenwei; Peng, Bo [CAS Key Laboratory for Researches in Galaxies and Cosmology, University of Sciences and Technology of China, Hefei, Anhui 230026 (China); Yan, Lin [Caltech Optical Observatories, Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Dou, Liming, E-mail: shengzf@mail.ustc.edu.cn, E-mail: twang@ustc.edu.cn [Center for Astrophysics, Guangzhou University, Guangzhou 510006 (China)

    2017-09-01

    It is known that some active galactic nuclei (AGNs) transit from Type 1 to Type 2 or vice versa. There are two explanations for the so-called changing-look AGNs: one is the dramatic change of the obscuration along the line of sight, and the other is the variation of accretion rate. In this Letter, we report the detection of large amplitude variations in the mid-infrared luminosity during the transitions in 10 changing-look AGNs using the Wide-field Infrared Survey Explorer ( WISE ) and newly released Near-Earth Object WISE Reactivation data. The mid-infrared light curves of 10 objects echo the variability in the optical band with a time lag expected for dust reprocessing. The large variability amplitude is inconsistent with the scenario of varying obscuration, rather it supports the scheme of dramatic change in the accretion rate.

  17. Direction: unified theory of interactions

    International Nuclear Information System (INIS)

    Valko, P.

    1987-01-01

    Briefly characterized are the individual theories, namely, the general relativity theory, the Kaluza-Klein theory, the Weyl theory, the unified theory of electromagnetic and weak interactions, the supergravity theory, and the superstring theory. The history is recalled of efforts aimed at creating a unified theory of interactions, and future prospects are outlined. (M.D.). 2 figs

  18. Grand unified theories. Pt. 2

    International Nuclear Information System (INIS)

    Ellis, J.

    1982-01-01

    The author gives an introduction to the construction of grand unified theories on the base of the SU(3)xSU(2)xU(1) model of the strong, weak, and electromagnetic interactions. Especially he discusses the proton decay, neutrino masses and oscillations, and cosmological implications in connection with grand unified theories. (orig./HSI)

  19. Delayed or No Feedback? Gas Outflows in Type 2 AGNs. III

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Jong-Hak; Son, Donghoon; Bae, Hyun-Jin, E-mail: woo@astro.snu.ac.kr, E-mail: hjbae@galaxy.yonsei.ac.kr [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2017-04-20

    We present gas kinematics based on the [O iii] λ 5007 line and their connection to galaxy gravitational potential, active galactic nucleus (AGN) energetics, and star formation, using a large sample of ∼110,000 AGNs and star-forming (SF) galaxies at z < 0.3. Gas and stellar velocity dispersions are comparable to each other in SF galaxies, indicating that the ionized gas kinematics can be accounted by the gravitational potential of host galaxies. In contrast, AGNs clearly show non-gravitational kinematics, which is comparable to or stronger than the virial motion caused by the gravitational potential. The [O iii] velocity–velocity dispersion (VVD) diagram dramatically expands toward high values as a function of AGN luminosity, implying that the outflows are AGN-driven, while SF galaxies do not show such a trend. We find that the fraction of AGNs with a signature of outflow kinematics, steeply increases with AGN luminosity and Eddington ratio. In particular, the majority of luminous AGNs presents strong non-gravitational kinematics in the [O iii] profile. AGNs with strong outflow signatures show on average similar specific star formation rates (sSFRs) to those of star-forming galaxies. In contrast, AGNs with weak or no outflows have an order of magnitude lower sSFRs, suggesting that AGNs with current strong outflows do now show any negative AGN feedback and that it may take dynamical time to impact on star formation over galactic scales.

  20. Dynamics and Formation of Obscuring Tori in AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Bannikova, Elena Yu.; Sergeyev, Alexey V., E-mail: bannikova@astron.kharkov.ua [Institute of Radio Astronomy, National Academy of Science of Ukraine, Kharkiv (Ukraine); Institute of Astronomy, V. N. Karazin Kharkiv National University, Kharkiv (Ukraine)

    2017-12-12

    We considered the evolution of a self-gravitating clumpy torus in the gravitational field of the central mass of an active galactic nucleus (AGN) in the framework of the N-body problem. The initial conditions take into account winds with different opening angles. Results of our N-body simulations show that the clouds moving on orbits with a spread in inclinations and eccentricities form a toroidal region. The velocity of the clouds at the inner boundary of the torus is lower than in a disk model that can explain the observed rotation curves. We discuss the scenario of torus formation related with the beginning of the AGN stage.

  1. Testing a double AGN hypothesis for Mrk 273

    Science.gov (United States)

    Iwasawa, K.; U, V.; Mazzarella, J. M.; Medling, A. M.; Sanders, D. B.; Evans, A. S.

    2018-04-01

    The ultra-luminous infrared galaxy (ULIRG) Mrk 273 contains two infrared nuclei, N and SW, separated by 1 arcsecond. A Chandra observation has identified the SW nucleus as an absorbed X-ray source with NH 4 × 1023 cm-2 but also hinted at the possible presence of a Compton-thick AGN in the N nucleus, where a black hole of 109 M⊙ is inferred from the ionized gas kinematics. The intrinsic X-ray spectral slope recently measured by NuSTAR is unusually hard (Γ 1.3) for a Seyfert nucleus, for which we seek an alternative explanation. We hypothesize a strongly absorbed X-ray source in N, of which X-ray emission rises steeply above 10 keV, in addition to the known X-ray source in SW, and test it against the NuSTAR data, assuming the standard spectral slope (Γ = 1.9). This double X-ray source model gives a good explanation of the hard continuum spectrum, deep Fe K absorption edge, and strong Fe K line observed in this ULIRG, without invoking the unusual spectral slope required for a single source interpretation. The putative X-ray source in N is found to be absorbed by NH = 1.4+0.7-0.4 × 1024 cm-2. The estimated 2-10 keV luminosity of the N source is 1.3 × 1043 erg s-1, about a factor of 2 larger than that of SW during the NuSTAR observation. Uncorrelated variability above and below 10 keV between the Suzaku and NuSTAR observations appears to support the double source interpretation. Variability in spectral hardness and Fe K line flux between the previous X-ray observations is also consistent with this picture.

  2. OPC unified architecture

    CERN Document Server

    Mahnke, Wolfgang; Damm, Matthias

    2009-01-01

    The OPC Foundation defines standards for online data exchange between automation systems. They address access to current data (OPC DA), alarms and events (OPC A&E) and historical data (OPC HDA). This book presents an introduction into OPC UA and explains the concepts of the standard and other topics that are not directly addressed by the standard.

  3. Seven Deadliest Unified Communications Attacks

    CERN Document Server

    York, Dan

    2010-01-01

    Do you need to keep up with the latest hacks, attacks, and exploits effecting Unified Communications technology? Then you need Seven Deadliest Unified Communication Attacks. This book pinpoints the most dangerous hacks and exploits specific to Unified Communications, laying out the anatomy of these attacks including how to make your system more secure. You will discover the best ways to defend against these vicious hacks with step-by-step instruction and learn techniques to make your computer and network impenetrable. Attacks featured in this book include: UC Ecosystem Attacks Insecure Endpo

  4. AGN Outflow Shocks on Bonnor–Ebert Spheres

    Energy Technology Data Exchange (ETDEWEB)

    Dugan, Zachary; Silk, Joseph; Rahman, Mubdi [The Johns Hopkins University Department of Physics and Astronomy, Bloomberg Center for Physics and Astronomy, Room 366, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Gaibler, Volker [Universität Heidelberg, Zentrum für Astronomie, Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany); Bieri, Rebekka [Institut d’Astrophysique de Paris, UMR 7095, CNRS, UPMC Univ. Paris VI, 98 bis Boulevard Arago, F-75014 Paris (France)

    2017-04-20

    Feedback from active galactic nuclei (AGNs) and subsequent jet cocoons and outflow bubbles can have a significant impact on star formation in the host galaxy. To investigate feedback physics on small scales, we perform hydrodynamic simulations of realistically fast AGN winds striking Bonnor–Ebert spheres and examine gravitational collapse and ablation. We test AGN wind velocities ranging from 300 to 3000 km s{sup −1} and wind densities ranging from 0.5 to 10 m {sub p} cm{sup −3}. We include heating and cooling of low- and high-temperature gas, self-gravity, and spatially correlated perturbations in the shock, with a maximum resolution of 0.01 pc. We find that the ram pressure is the most important factor that determines the fate of the cloud. High ram pressure winds increase fragmentation and decrease the star formation rate, but they also cause star formation to occur on a much shorter timescale and with increased velocities of the newly formed stars. We find a threshold ram pressure of ∼2 × 10{sup −8} dyn cm{sup −2} above which stars are not formed because the resulting clumps have internal velocities large enough to prevent collapse. Our results indicate that simultaneous positive and negative feedback will be possible in a single galaxy, as AGN wind parameters will vary with location within a galaxy.

  5. The search for red AGN with 2MASS

    Science.gov (United States)

    Cutri, R. M.; Nelson, B. O.; Kirkpatrick, J. D.; Huchra, J. P.; Smith, P. S.

    2001-01-01

    We present the results of a simple, highly efficient 2MASS color-based survey that has already discovered 140 previously unknown red AGN and QSOs. These objects are near-infrared-bright and relatively nearby; the media redshift of the sample is z=0.25, and all but two have z<0.7.

  6. Beyond Hydrodynamic Modeling of AGN Heating in Galaxy Clusters

    Science.gov (United States)

    Yang, Hsiang-Yi Karen

    Clusters of galaxies hold a unique position in hierarchical structure formation - they are both powerful cosmological probes and excellent astrophysical laboratories. Accurate modeling of the cluster properties is crucial for reducing systematic uncertainties in cluster cosmology. However, theoretical modeling of the intracluster medium (ICM) has long suffered from the "cooling-flow problem" - clusters with short central times or cool cores (CCs) are predicted to host massive inflows of gas that are not observed. Feedback from active galactic nuclei (AGN) is by far the most promising heating mechanism to counteract radiative cooling. Recent hydrodynamic simulations have made remarkable progress reproducing properties of the CCs. However, there remain two major questions that cannot be probed using purely hydrodynamic models: (1) what are the roles of cosmic rays (CRs)? (2) how is the existing picture altered when the ICM is modeled as weakly collisional plasma? We propose to move beyond limitations of pure hydrodynamics and progress toward a complete understanding of how AGN jet-inflated bubbles interact with their surroundings and provide heat to the ICM. Our objectives include: (1) understand how CR-dominated bubbles heat the ICM; (2) understand bubble evolution and sound-wave dissipation in the ICM with different assumptions of plasma properties, e.g., collisionality of the ICM, with or without anisotropic transport processes; (3) Develop a subgrid model of AGN heating that can be adopted in cosmological simulations based on state-of-the-art isolated simulations. We will use a combination of analytical calculations and idealized simulations to advance our understanding of each individual physical process. We will then perform the first three-dimensional (3D) magnetohydrodynamic (MHD) simulations of self-regulated AGN feedback with relevant CR and anisotropic transport processes in order to quantify the amount and distribution of heating from the AGN. Our

  7. Understanding AGNs in the Local Universe through Optical Reverberation Mapping

    Science.gov (United States)

    Pei, Liuyi

    2016-01-01

    I present the results of observational projects aimed at measuring the mass of the black hole at the center of active galactic nuclei (AGNs) and understanding the structure and kinematics of the broad-line emitting gas within the black hole's sphere of influence.The first project aims to measure the black hole mass in the Kepler-field AGN KA1858. We obtained simultaneous spectroscopic data from the Lick Observatory 3-m telescope using the Kast Double Spectrograph and photometry data from five ground-based telescopes, and used reverberation mapping (RM) techniques to measure the emission-line light curves' lags relative to continuum variations. We obtained lags for H-beta, H-gamma, H-delta, and He II, and obtained the first black hole mass measurement for this object. Our results will serve as a reference point for future studies on relations between black hole mass and continuum variability characteristics using Kepler AGN light curves.The second project, in collaboration with the AGN STORM team, aims to understand the structure and dynamics of the broad line region (BLR) in NGC 5548 in both UV and optical wavelengths. To supplement 6 months of HST UV observations, we obtained simultaneous optical spectroscopic data from six ground-based observatories. We obtained emission-line lags for the optical H-beta and He II lines as well as velocity-resolved lag measurements for H-beta. We also compared the velocity-resolved lags for H-beta to the UV emission lines C IV and Ly-alpha and found similar lag profiles for all three lines.Finally, I will discuss my contributions to two other collaborations in AGN RM. A key component in RM is monitoring continuum variability, which is often done through ground-based photometry. I will present a pipeline that performs aperture photometry on any number of images of an AGN with WCS coordinates and immediately produces relative light curves. This pipeline enables quick looks of AGN variability in real time and has been used in the

  8. UPQC (Unified power Quality Conditioner)

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. UPQC (Unified power Quality Conditioner). Hybrid of Shunt and Series compensator. Compensate both Current Quality and Voltage Quality. Costlier Solution as it involves two set of Inverters.

  9. AGNs with discordant optical and X-ray classification are not a physical family: diverse origin in two AGNs

    Science.gov (United States)

    Ordovás-Pascual, I.; Mateos, S.; Carrera, F. J.; Wiersema, K.; Barcons, X.; Braito, V.; Caccianiga, A.; Del Moro, A.; Della Ceca, R.; Severgnini, P.

    2017-07-01

    Approximately 3-17 per cent of active galactic nuclei (AGNs) without detected rest-frame UV/optical broad emission lines (type-2 AGN) do not show absorption in X-rays. The physical origin behind the apparently discordant optical/X-ray properties is not fully understood. Our study aims at providing insight into this issue by conducting a detailed analysis of the nuclear dust extinction and X-ray absorption properties of two AGNs with low X-ray absorption and with high optical extinction, for which a rich set of high-quality spectroscopic data is available from XMM-Newton archive data in X-rays and XSHOOTER proprietary data at UV-to-NIR wavelengths. In order to unveil the apparent mismatch, we have determined the AV/NH and both the supermassive black hole and the host galaxy masses. We find that the mismatch is caused in one case by an abnormally high dust-to-gas ratio that makes the UV/optical emission to appear more obscured than in the X-rays. For the other object, we find that the dust-to-gas ratio is similar to the Galactic one but the AGN is hosted by a very massive galaxy so that the broad emission lines and the nuclear continuum are swamped by the star light and difficult to detect.

  10. Model of unified gauge fields

    International Nuclear Information System (INIS)

    Leite Lopes, J.

    1998-04-01

    In this work, we discuss the physical ideas which represents the basis for the unified gauge field model. Despite of the difficulties that we presently have for embodying in a natural manner muons and hadrons in that model, we have the feeling that we are on the way which seems to lead to the construction of a theory in which the Maxwell electromagnetic field and the Fermi weak interaction field are manifestations of a unique subjacent physical entity - the unified gauge fields. (author)

  11. BAT AGN Spectroscopic Survey - III. An Observed Link Between AGN Eddington Ratio and Narrow-Emission-Line Ratios

    Science.gov (United States)

    Oh, Kyuseok; Schawinski, Kevin; Koss, Michael; Trakhtenbrot, Benny; Lamperti, Isabella; Ricci, Claudio; Mushotzky, Richard; Veilleux, Sylvain; Berney, Simon; Crenshaw, D. Michael; hide

    2016-01-01

    We investigate the observed relationship between black hole mass (M(sub BH)), bolometric luminosity (L(sub bol)) and Eddington ratio (lambda(sub Edd)) with optical emission-line ratios ([N II] lambda6583/Halpha, [S II]lambda-lamda6716, 6731/Halpha, [O I] lamda6300/Halpha, [O III] lamda5007/Hbeta, [Ne III] lamda3869/Hbeta and He II lamda4686/Hbeta) of hard X-ray-selected active galactic nuclei (AGN) from the BAT AGN Spectroscopic Survey. We show that the [N II] lamda6583/Halpha ratio exhibits a significant correlation with lamda(sub Edd) (R(sub Pear) = -0.44, p-value 3 x 10(exp. -13) sigma = 0.28 dex), and the correlation is not solely driven by M(sub BH) or L(sub bol). The observed correlation between [N II] lamda6583/Halpha ratio and M(sub BH) is stronger than the correlation with L(sub bol), but both are weaker than the lamda(sub Edd) correlation. This implies that the large-scale narrow lines of AGN host galaxies carry information about the accretion state of the AGN central engine. We propose that [N II] lamda6583/Halpha is a useful indicator of Eddington ratio with 0.6 dex of rms scatter, and that it can be used to measure lambda(sub Edd) and thus M(sub BH) from the measured L(sub bol), even for high-redshift obscured AGN. We briefly discuss possible physical mechanisms behind this correlation, such as the mass-metallicity relation, X-ray heating, and radiatively driven outflows.

  12. DUAL SUPERMASSIVE BLACK HOLE CANDIDATES IN THE AGN AND GALAXY EVOLUTION SURVEY

    International Nuclear Information System (INIS)

    Comerford, Julia M.; Schluns, Kyle; Greene, Jenny E.; Cool, Richard J.

    2013-01-01

    Dual supermassive black holes (SMBHs) with kiloparsec-scale separations in merger-remnant galaxies are informative tracers of galaxy evolution, but the avenue for identifying them in large numbers for such studies is not yet clear. One promising approach is to target spectroscopic signatures of systems where both SMBHs are fueled as dual active galactic nuclei (AGNs), or where one SMBH is fueled as an offset AGN. Dual AGNs may produce double-peaked narrow AGN emission lines, while offset AGNs may produce single-peaked narrow AGN emission lines with line-of-sight velocity offsets relative to the host galaxy. We search for such dual and offset systems among 173 Type 2 AGNs at z +3.6 -1.9 % to 18 +5 -5 %). This may be associated with the rise in the galaxy merger fraction over the same cosmic time. As further evidence for a link with galaxy mergers, the AGES offset and dual AGN candidates are tentatively ∼3 times more likely than the overall AGN population to reside in a host galaxy that has a companion galaxy (from 16/173 to 2/7, or 9 +3 -2 % to 29 -19 +26 %). Follow-up observations of the seven offset and dual AGN candidates in AGES will definitively distinguish velocity offsets produced by dual SMBHs from those produced by narrow-line region kinematics, and will help sharpen our observational approach to detecting dual SMBHs

  13. The fraction of AGNs in major merger galaxies and its luminosity dependence

    Science.gov (United States)

    Weigel, Anna K.; Schawinski, Kevin; Treister, Ezequiel; Trakhtenbrot, Benny; Sanders, David B.

    2018-05-01

    We use a phenomenological model which connects the galaxy and active galactic nucleus (AGN) populations to investigate the process of AGNs triggering through major galaxy mergers at z ˜ 0. The model uses stellar mass functions as input and allows the prediction of AGN luminosity functions based on assumed Eddington ratio distribution functions (ERDFs). We show that the number of AGNs hosted by merger galaxies relative to the total number of AGNs increases as a function of AGN luminosity. This is due to more massive galaxies being more likely to undergo a merger and does not require the assumption that mergers lead to higher Eddington ratios than secular processes. Our qualitative analysis also shows that to match the observations, the probability of a merger galaxy hosting an AGN and accreting at a given Eddington value has to be increased by a factor ˜10 relative to the general AGN population. An additional significant increase of the fraction of high Eddington ratio AGNs among merger host galaxies leads to inconsistency with the observed X-ray luminosity function. Physically our results imply that, compared to the general galaxy population, the AGN fraction among merger galaxies is ˜10 times higher. On average, merger triggering does however not lead to significantly higher Eddington ratios.

  14. Radio Loud AGN Unification: Connecting Jets and Accretion

    Directory of Open Access Journals (Sweden)

    Meyer Eileen T.

    2013-12-01

    Full Text Available While only a fraction of Active Galactic Nuclei are observed to host a powerful relativistic jet, a cohesive picture is emerging that radio-loud AGN may represent an important phase in the evolution of galaxies and the growth of the central super-massive black hole. I will review my own recent observational work in radio-loud AGN unification in the context of understanding how and why jets form and their the connection to different kinds of accretion and growing the black hole, along with a brief discussion of possible connections to recent modeling work in jet formation. Starting from the significant observational advances in our understanding of jetted AGN as a population over the last decade thanks to new, more sensitive instruments such as Fermi and Swift as well as all-sky surveys at all frequencies, I will lay out the case for a dichotomy in the jetted AGN population connected to accretion mode onto the black hole. In recent work, we have identified two sub-populations of radio-loud AGN which appear to be distinguished by jet structure, where low-efficiency accreting systems produce ‘weak’ jets which decelerate more rapidly than the ’strong’ jets of black holes accreting near the Eddington limit. The two classes are comprised of: (1The weak jet sources, corresponding to the less collimated, edge-darkened FR Is, with a decelerating or spine-sheath jet with velocity gradients, and (2 The strong jet sources, having fast, collimated jets, and typically displaying strong emission lines. The dichotomy in the vp-Lp plane can be understood as a "broken power sequence" in which jets exist on one branch or the other based on the particular accretion mode (Georganopolous 2011.We suggest that the intrinsic kinetic power (as measured by low-frequency, isotropic radio emission, the orientation, and the accretion rate of the SMBH system are the the fundamental axes needed for unification of radio-loud AGN by studying a well-characterized sample

  15. Stochastic particle acceleration by plasma waves in AGN jets

    International Nuclear Information System (INIS)

    Li, Hui; Colgate, S.A.; Miller, J.A.

    1997-01-01

    The free energy stored in the stressed magnetic fields in AGN jets could be dissipated via generating turbulent plasma waves. The authors review several key wave-particle resonant interactions and point out the importance of a broad wave spectrum. Under several idealized assumptions, they show that the transit-time damping process can accelerate electrons to TeV energies in an AGN jet environment, and present a preliminary calculation on the evolution of plasma wave, electron, and photon distributions. The authors especially emphasize several open questions on particle acceleration by waves, and argue that a plausible scenario is to energize electrons out of the thermal background via transit-time damping and further accelerate them by the parallel propagating right-handed waves

  16. AGN Heating in Simulated Cool-core Clusters

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yuan; Ruszkowski, Mateusz [Department of Astronomy, University of Michigan, 1085 S. University Avenue, Ann Arbor, MI 48109 (United States); Bryan, Greg L., E-mail: yuanlium@umich.edu [Department of Astronomy, Columbia University, Pupin Physics Laboratories, New York, NY 10027 (United States)

    2017-10-01

    We analyze heating and cooling processes in an idealized simulation of a cool-core cluster, where momentum-driven AGN feedback balances radiative cooling in a time-averaged sense. We find that, on average, energy dissipation via shock waves is almost an order of magnitude higher than via turbulence. Most of the shock waves in the simulation are very weak shocks with Mach numbers smaller than 1.5, but the stronger shocks, although rare, dissipate energy more effectively. We find that shock dissipation is a steep function of radius, with most of the energy dissipated within 30 kpc, more spatially concentrated than radiative cooling loss. However, adiabatic processes and mixing (of post-shock materials and the surrounding gas) are able to redistribute the heat throughout the core. A considerable fraction of the AGN energy also escapes the core region. The cluster goes through cycles of AGN outbursts accompanied by periods of enhanced precipitation and star formation, over gigayear timescales. The cluster core is under-heated at the end of each cycle, but over-heated at the peak of the AGN outburst. During the heating-dominant phase, turbulent dissipation alone is often able to balance radiative cooling at every radius but, when this is occurs, shock waves inevitably dissipate even more energy. Our simulation explains why some clusters, such as Abell 2029, are cooling dominated, while in some other clusters, such as Perseus, various heating mechanisms including shock heating, turbulent dissipation and bubble mixing can all individually balance cooling, and together, over-heat the core.

  17. Announcment: Conference on Obscured AGN Across Cosmic Time

    Science.gov (United States)

    2006-12-01

    Current deep surveys, notably in X-rays and the mid-IR, are making it possible to carry out a census of essentially all the luminous AGN in the Universe. By pene-trating the obscuration that, in Type 2 sources, hides the nuclear regions in the UV to the near-IR spectrum, these new surveys are finding the radio quiet coun-terparts of the powerful radio galaxies.

  18. Clustering of galaxies around AGNs in the HSC Wide survey

    Science.gov (United States)

    Shirasaki, Yuji; Akiyama, Masayuki; Nagao, Tohru; Toba, Yoshiki; He, Wanqiu; Ohishi, Masatoshi; Mizumoto, Yoshihiko; Miyazaki, Satoshi; Nishizawa, Atsushi J.; Usuda, Tomonori

    2018-01-01

    We have measured the clustering of galaxies around active galactic nuclei (AGNs) for which single-epoch virial masses of the super-massive black hole (SMBH) are available to investigate the relation between the large-scale environment of AGNs and the evolution of SMBHs. The AGN samples used in this work were derived from the Sloan Digital Sky Survey (SDSS) observations and the galaxy samples were from the 240 deg2 S15b data of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). The investigated redshift range is 0.6-3.0, and the masses of the SMBHs lie in the range 107.5-1010 M⊙. The absolute magnitude of the galaxy samples reaches to Mλ310 ˜ -18 at rest-frame wavelength 310 nm for the low-redshift end of the samples. More than 70% of the galaxies in the analysis are blue. We found a significant dependence of the cross-correlation length on redshift, which primarily reflects the brightness-dependence of the galaxy clustering. At the lowest redshifts the cross-correlation length increases from 7 h-1 Mpc around Mλ310 = -19 mag to >10 h-1 Mpc beyond Mλ310 = -20 mag. No significant dependence of the cross-correlation length on BH mass was found for whole galaxy samples dominated by blue galaxies, while there was an indication of BH mass dependence in the cross-correlation with red galaxies. These results provides a picture of the environment of AGNs studied in this paper being enriched with blue star-forming galaxies, and a fraction of the galaxies are evolving into red galaxies along with the evolution of SMBHs in that system.

  19. SO(10) supersymmetric grand unified theories

    Science.gov (United States)

    Dermisek, Radovan

    The origin of the fermion mass hierarchy is one of the most challenging problems in elementary particle physics. In the standard model fermion masses and mixing angles are free parameters. Supersymmetric grand unified theories provide a beautiful framework for physics beyond the standard model. In addition to gauge coupling unification these theories provide relations between quark and lepton masses within families, and with additional family symmetry the hierarchy between families can be generated. We present a predictive SO(10) supersymmetric grand unified model with D 3 x U(1) family symmetry. The hierarchy in fermion masses is generated by the family symmetry breaking D 3 x U(1) → ZN → nothing. This model fits the low energy data in the charged fermion sector quite well. We discuss the prediction of this model for the proton lifetime in light of recent SuperKamiokande results and present a clear picture of the allowed spectra of supersymmetric particles. Finally, the detailed discussion of the Yukawa coupling unification of the third generation particles is provided. We find a narrow region is consistent with t, b, tau Yukawa unification for mu > 0 (suggested by b → sgamma and the anomalous magnetic moment of the muon) with A0 ˜ -1.9m16, m10 ˜ 1.4m16, m16 ≳ 1200 GeV and mu, M1/2 ˜ 100--500 GeV. Demanding Yukawa unification thus makes definite predictions for Higgs and sparticle masses.

  20. A unified dynamics for micro and macrosystems

    International Nuclear Information System (INIS)

    Ghirardi, G.C.; Rimini, A.; Weber, T.

    1985-12-01

    An explicit model allowing a unified description of micro and macrosystems is exhibited. Firstly, a modified quantum dynamics for the description of macroobjects is constructed and it is shown that it forbids the occurrence of linear superpositions of states localized in far away spatial regions and induces an evolution agreeing with classical mechanics. This dynamics also allows a description of the evolution in terms of trajectories. To set up a unified description of all physical phenomena, a modification of the dynamics, with respect to the standard Hamiltonian one, is then postulated also for microscopic systems. It is shown that one can consistently deduce from it the previously considered dynamics for the centre of mass of macroscopic systems. Choosing in an appropriate way the parameters of the so obtained model one can show that the standard quantum theory for microobjects, the quantum mechanical wave packet reduction with fixed pointer positions, and the classical behaviour for macroobjects can be all derived in a consistent way. Moreover, in the case of a macroscopic system one can obtain, by means of appropriate approximations, a description of the evolution in terms of a phase-space density distribution obeying a Fokker-Planck diffusion equation. (author)

  1. Group theory for unified model building

    International Nuclear Information System (INIS)

    Slansky, R.

    1981-01-01

    The results gathered here on simple Lie algebras have been selected with attention to the needs of unified model builders who study Yang-Mills theories based on simple, local-symmetry groups that contain as a subgroup the SUsup(w) 2 x Usup(w) 1 x SUsup(c) 3 symmetry of the standard theory of electromagnetic, weak, and strong interactions. The major topics include, after a brief review of the standard model and its unification into a simple group, the use of Dynkin diagrams to analyze the structure of the group generators and to keep track of the weights (quantum numbers) of the representation vectors; an analysis of the subgroup structure of simple groups, including explicit coordinatizations of the projections in weight space; lists of representations, tensor products and branching rules for a number of simple groups; and other details about groups and their representations that are often helpful for surveying unified models, including vector-coupling coefficient calculations. Tabulations of representations, tensor products, and branching rules for E 6 , SO 10 , SU 6 , F 4 , SO 9 , SO 5 , SO 8 , SO 7 , SU 4 , E 7 , E 8 , SU 8 , SO 14 , SO 18 , SO 22 , and for completeness, SU 3 are included. (These tables may have other applications.) Group-theoretical techniques for analyzing symmetry breaking are described in detail and many examples are reviewed, including explicit parameterizations of mass matrices. (orig.)

  2. Subgrid Modeling of AGN-driven Turbulence in Galaxy Clusters

    Science.gov (United States)

    Scannapieco, Evan; Brüggen, Marcus

    2008-10-01

    Hot, underdense bubbles powered by active galactic nuclei (AGNs) are likely to play a key role in halting catastrophic cooling in the centers of cool-core galaxy clusters. We present three-dimensional simulations that capture the evolution of such bubbles, using an adaptive mesh hydrodynamic code, FLASH3, to which we have added a subgrid model of turbulence and mixing. While pure hydro simulations indicate that AGN bubbles are disrupted into resolution-dependent pockets of underdense gas, proper modeling of subgrid turbulence indicates that this is a poor approximation to a turbulent cascade that continues far beyond the resolution limit. Instead, Rayleigh-Taylor instabilities act to effectively mix the heated region with its surroundings, while at the same time preserving it as a coherent structure, consistent with observations. Thus, bubbles are transformed into hot clouds of mixed material as they move outward in the hydrostatic intracluster medium (ICM), much as large airbursts lead to a distinctive "mushroom cloud" structure as they rise in the hydrostatic atmosphere of Earth. Properly capturing the evolution of such clouds has important implications for many ICM properties. In particular, it significantly changes the impact of AGNs on the distribution of entropy and metals in cool-core clusters such as Perseus.

  3. Modeling AGN outbursts from supermassive black hole binaries

    Directory of Open Access Journals (Sweden)

    Tanaka T.

    2012-12-01

    Full Text Available When galaxies merge to assemble more massive galaxies, their nuclear supermassive black holes (SMBHs should form bound binaries. As these interact with their stellar and gaseous environments, they will become increasingly compact, culminating in inspiral and coalescence through the emission of gravitational radiation. Because galaxy mergers and interactions are also thought to fuel star formation and nuclear black hole activity, it is plausible that such binaries would lie in gas-rich environments and power active galactic nuclei (AGN. The primary difference is that these binaries have gravitational potentials that vary – through their orbital motion as well as their orbital evolution – on humanly tractable timescales, and are thus excellent candidates to give rise to coherent AGN variability in the form of outbursts and recurrent transients. Although such electromagnetic signatures would be ideally observed concomitantly with the binary’s gravitational-wave signatures, they are also likely to be discovered serendipitously in wide-field, high-cadence surveys; some may even be confused for stellar tidal disruption events. I discuss several types of possible “smoking gun” AGN signatures caused by the peculiar geometry predicted for accretion disks around SMBH binaries.

  4. Development of the criticality accident analysis code, AGNES

    International Nuclear Information System (INIS)

    Nakajima, Ken

    1989-01-01

    In the design works for the facilities which handle nuclear fuel, the evaluation of criticality accidents cannot be avoided even if their possibility is as small as negligible. In particular in the system using solution fuel like uranyl nitrate, solution has the property easily becoming dangerous form, and all the past criticality accidents occurred in the case of solution, therefore, the evaluation of criticality accidents becomes the most important item of safety analysis. When a criticality accident occurred in a solution fuel system, due to the generation and movement of radiolysis gas voids, the oscillation of power output and pressure pulses are observed. In order to evaluate the effect of criticality accidents, these output oscillation and pressure pulses must be calculated accurately. For this purpose, the development of the dynamic characteristic code AGNES (Accidentally Generated Nuclear Excursion Simulation code) was carried out. The AGNES is the reactor dynamic characteristic code having two independent void models. Modified energy model and pressure model, and as the benchmark calculation of the AGNES code, the results of the experimental analysis on the CRAC experiment are reported. (K.I.)

  5. The Kepler Light Curves of AGN: A Detailed Analysis

    Science.gov (United States)

    Smith, Krista Lynne; Mushotzky, Richard F.; Boyd, Patricia T.; Malkan, Matt; Howell, Steve B.; Gelino, Dawn M.

    2018-04-01

    We present a comprehensive analysis of 21 light curves of Type 1 active galactic nuclei (AGN) from the Kepler spacecraft. First, we describe the necessity and development of a customized pipeline for treating Kepler data of stochastically variable sources like AGN. We then present the light curves, power spectral density functions (PSDs), and flux histograms. The light curves display an astonishing variety of behaviors, many of which would not be detected in ground-based studies, including switching between distinct flux levels. Six objects exhibit PSD flattening at characteristic timescales that roughly correlate with black hole mass. These timescales are consistent with orbital timescales or free-fall accretion timescales. We check for correlations of variability and high-frequency PSD slope with accretion rate, black hole mass, redshift, and luminosity. We find that bolometric luminosity is anticorrelated with both variability and steepness of the PSD slope. We do not find evidence of the linear rms–flux relationships or lognormal flux distributions found in X-ray AGN light curves, indicating that reprocessing is not a significant contributor to optical variability at the 0.1%–10% level.

  6. Compton Reflection in AGN with Simbol-X

    Science.gov (United States)

    Beckmann, V.; Courvoisier, T. J.-L.; Gehrels, N.; Lubiński, P.; Malzac, J.; Petrucci, P. O.; Shrader, C. R.; Soldi, S.

    2009-05-01

    AGN exhibit complex hard X-ray spectra. Our current understanding is that the emission is dominated by inverse Compton processes which take place in the corona above the accretion disk, and that absorption and reflection in a distant absorber play a major role. These processes can be directly observed through the shape of the continuum, the Compton reflection hump around 30 keV, and the iron fluorescence line at 6.4 keV. We demonstrate the capabilities of Simbol-X to constrain complex models for cases like MCG-05-23-016, NGC 4151, NGC 2110, and NGC 4051 in short (10 ksec) observations. We compare the simulations with recent observations on these sources by INTEGRAL, Swift and Suzaku. Constraining reflection models for AGN with Simbol-X will help us to get a clear view of the processes and geometry near to the central engine in AGN, and will give insight to which sources are responsible for the Cosmic X-ray background at energies >20 keV.

  7. Formation and spatial distribution of hypervelocity stars in AGN outflows

    Science.gov (United States)

    Wang, Xiawei; Loeb, Abraham

    2018-05-01

    We study star formation within outflows driven by active galactic nuclei (AGN) as a new source of hypervelocity stars (HVSs). Recent observations revealed active star formation inside a galactic outflow at a rate of ∼ 15M⊙yr-1 . We verify that the shells swept up by an AGN outflow are capable of cooling and fragmentation into cold clumps embedded in a hot tenuous gas via thermal instabilities. We show that cold clumps of ∼ 103 M⊙ are formed within ∼ 105 yrs. As a result, stars are produced along outflow's path, endowed with the outflow speed at their formation site. These HVSs travel through the galactic halo and eventually escape into the intergalactic medium. The expected instantaneous rate of star formation inside the outflow is ∼ 4 - 5 orders of magnitude greater than the average rate associated with previously proposed mechanisms for producing HVSs, such as the Hills mechanism and three-body interaction between a star and a black hole binary. We predict the spatial distribution of HVSs formed in AGN outflows for future observational probe.

  8. Physical Conditions in Ultra-fast Outflows in AGN

    Science.gov (United States)

    Kraemer, S. B.; Tombesi, F.; Bottorff, M. C.

    2018-01-01

    XMM-Newton and Suzaku spectra of Active Galactic Nuclei (AGN) have revealed highly ionized gas, in the form of absorption lines from H-like and He-like Fe. Some of these absorbers, ultra-fast outflows (UFOs), have radial velocities of up to 0.25c. We have undertaken a detailed photoionization study of high-ionization Fe absorbers, both UFOs and non-UFOs, in a sample of AGN observed by XMM-Newton. We find that the heating and cooling processes in UFOs are Compton-dominated, unlike the non-UFOs. Both types are characterized by force multipliers on the order of unity, which suggest that they cannot be radiatively accelerated in sub-Eddington AGN, unless they were much less ionized at their point of origin. However, such highly ionized gas can be accelerated via a magneto-hydrodynamic (MHD) wind. We explore this possibility by applying a cold MHD flow model to the UFO in the well-studied Seyfert galaxy, NGC 4151. We find that the UFO can be accelerated along magnetic streamlines anchored in the accretion disk. In the process, we have been able to constrain the magnetic field strength and the magnetic pressure in the UFO and have determined that the system is not in magnetic/gravitational equipartition. Open questions include the variability of the UFOs and the apparent lack of non-UFOs in UFO sources.

  9. SDSS IV MaNGA - Properties of AGN Host Galaxies

    Science.gov (United States)

    Sánchez, S. F.; Avila-Reese, V.; Hernandez-Toledo, H.; Cortes-Suárez, E.; Rodríguez-Puebla, A.; Ibarra-Medel, H.; Cano-Díaz, M.; Barrera-Ballesteros, J. K.; Negrete, C. A.; Calette, A. R.; de Lorenzo-Cáceres, A.; Ortega-Minakata, R. A.; Aquino, E.; Valenzuela, O.; Clemente, J. C.; Storchi-Bergmann, T.; Riffel, R.; Schimoia, J.; Riffel, R. A.; Rembold, S. B.; Brownstein, J. R.; Pan, K.; Yates, R.; Mallmann, N.; Bitsakis, T.

    2018-04-01

    We present the characterization of the main properties of a sample of 98 AGN host galaxies, both type-II and type-I, in comparison with those of ≍2700 non-active galaxies observed by the MaNGA survey. We found that AGN hosts are morphologically early-type or early-spirals. AGN hosts are, on average, more massive, more compact, more centrally peaked and more pressure-supported systems. They are located in the intermediate/transition region between starforming and non-star-forming galaxies (i.e., the so-called green valley). We consider that they are in the process of halting/quenching the star formation. The analysis of the radial distributions of different properties shows that the quenching happens from inside-out involving both a decrease of the effciency of the star formation and a deficit of molecular gas. The data-products of the current analysis are distributed as a Value Added Catalog within the SDSS-DR14.

  10. Pair-Matching of Radio-Loud and Radio-Quiet AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Kozieł-Wierzbowska, Dorota [Astronomical Observatory, Jagiellonian University, Krakow (Poland); Stasińska, Grażyna [LUTH, Observatoire de Paris, Centre National de la Recherche Scientifique, Université Paris Diderot, Meudon (France); Vale Asari, Natalia [Departamento de Física–CFM, Universidade Federal de Santa Catarina, Florianópolis (Brazil); Sikora, Marek [Nicolaus Copernicus Astronomical Center, Warsaw (Poland); Goettems, Elisa [Departamento de Física–CFM, Universidade Federal de Santa Catarina, Florianópolis (Brazil); Wójtowicz, Anna, E-mail: dorota.koziel@uj.edu.pl [Astronomical Observatory, Jagiellonian University, Krakow (Poland)

    2017-11-07

    Active galactic nuclei (AGNs) are known to cover an extremely broad range of radio luminosities and the spread of their radio-loudness is very large at any value of the Eddington ratio. This implies very diverse jet production efficiencies which can result from the spread of the black hole spins and magnetic fluxes. Magnetic fluxes can be developed stochastically in the innermost zones of accretion discs, or can be advected to the central regions prior to the AGN phase. In the latter case there could be systematic differences between the properties of galaxies hosting radio-loud (RL) and radio-quiet (RQ) AGNs. In the former case the differences should be negligible for objects having the same Eddington ratio. To study the problem we decided to conduct a comparison study of host galaxy properties of RL and RQ AGNs. In this study we selected type II AGNs from SDSS spectroscopic catalogs. Our RL AGN sample consists of the AGNs appearing in the Best and Heckman (2012) catalog of radio galaxies. To compare RL and RQ galaxies that have the same AGN parameters we matched the galaxies in black hole mass, Eddington ratio and redshift. We compared several properties of the host galaxies in these two groups of objects like galaxy mass, color, concentration index, line widths, morphological type and interaction signatures. We found that in the studied group RL AGNs are preferentially hosted by elliptical galaxies while RQ ones are hosted by galaxies of later type. We also found that the fraction of interacting galaxies is the same in both groups of AGNs. These results suggest that the magnetic flux in RL AGNs is advected to the nucleus prior to the AGN phase.

  11. X-RAY ABSORPTION, NUCLEAR INFRARED EMISSION, AND DUST COVERING FACTORS OF AGNs: TESTING UNIFICATION SCHEMES

    Energy Technology Data Exchange (ETDEWEB)

    Mateos, S.; Carrera, F. J.; Alonso-Herrero, A.; Hernán-Caballero, A.; Barcons, X. [Instituto de Física de Cantabria (CSIC-Universidad de Cantabria), E-39005, Santander (Spain); Ramos, A. Asensio; Almeida, C. Ramos [Instituto de Astrofísica de Canarias, E-38205, La Laguna, Tenerife (Spain); Watson, M. G.; Blain, A. [Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Caccianiga, A.; Ballo, L. [INAF-Osservatorio Astronomico di Brera, via Brera 28, I-20121 Milano (Italy); Braito, V., E-mail: mateos@ifca.unican.es [INAF-Osservatorio Astronomico di Brera, Via Bianchi 46, I-23807 Merate (Italy)

    2016-03-10

    We present the distributions of the geometrical covering factors of the dusty tori (f{sub 2}) of active galactic nuclei (AGNs) using an X-ray selected complete sample of 227 AGNs drawn from the Bright Ultra-hard XMM-Newton Survey. The AGNs have z from 0.05 to 1.7, 2–10 keV luminosities between 10{sup 42} and 10{sup 46} erg s{sup −1}, and Compton-thin X-ray absorption. Employing data from UKIDSS, 2MASS, and the Wide-field Infrared Survey Explorer in a previous work, we determined the rest-frame 1–20 μm continuum emission from the torus, which we model here with the clumpy torus models of Nenkova et al. Optically classified type 1 and type 2 AGNs are intrinsically different, with type 2 AGNs having, on average, tori with higher f{sub 2} than type 1 AGNs. Nevertheless, ∼20% of type 1 AGNs have tori with large covering factors, while ∼23%–28% of type 2 AGNs have tori with small covering factors. Low f{sub 2} are preferred at high AGN luminosities, as postulated by simple receding torus models, although for type 2 AGNs the effect is certainly small. f{sub 2} increases with the X-ray column density, which implies that dust extinction and X-ray absorption take place in material that share an overall geometry and most likely belong to the same structure, the putative torus. Based on our results, the viewing angle, AGN luminosity, and also f{sub 2} determine the optical appearance of an AGN and control the shape of the rest-frame ∼1–20 μm nuclear continuum emission. Thus, the torus geometrical covering factor is a key ingredient of unification schemes.

  12. Adapting the unified software development process for user interface development

    NARCIS (Netherlands)

    Obrenovic, Z.; Starcevic, D.

    2006-01-01

    In this paper we describe how existing software developing processes, such as Rational Unified Process, can be adapted in order to allow disciplined and more efficient development of user interfaces. The main objective of this paper is to demonstrate that standard modeling environments, based on the

  13. The Simplest Unified Growth Theory

    DEFF Research Database (Denmark)

    Strulik, Holger; Weisdorf, Jacob Louis

    This paper provides a unified growth theory, i.e. a model that explains the very long-run economic and demographic development path of industrialized economies, stretching from the pre-industrial era to present-day and beyond. Making strict use of Malthus' (1798) so-called preventive check...... hypothesis - that fertility rates vary inversely with the price of food - the current study offers a new and straightforward explanation for the demographic transition and the break with the Malthusian era. The current framework lends support to existing unified growth theories and is well in tune...

  14. Higgsless grand unified theory breaking and trinification

    International Nuclear Information System (INIS)

    Carone, Christopher D.; Conroy, Justin M.

    2004-01-01

    Boundary conditions on an extra dimensional interval can be chosen to break bulk gauge symmetries and to reduce the rank of the gauge group. We consider this mechanism in models with gauge trinification. We determine the boundary conditions necessary to break the trinified gauge group directly down to that of the standard model. Working in an effective theory for the gauge-symmetry-breaking parameters on a boundary, we examine the limit in which the grand-unified theory-breaking-sector is Higgsless and show how one may obtain the low-energy particle content of the minimal supersymmetric standard model. We find that gauge unification is preserved in this scenario, and that the differential gauge coupling running is logarithmic above the scale of compactification. We compare the phenomenology of our model to that of four dimensional 'trinified' theories

  15. Toward a Unified Communication Theory.

    Science.gov (United States)

    McMillan, Saundra

    After discussing the nature of theory itself, the author explains her concept of the Unified Communication Theory, which rests on the assumption that there exists in all living structures a potential communication factor which is delimited by species and ontogeny. An organism develops "symbol fixation" at the level where its perceptual abilities…

  16. A model unified field equation

    International Nuclear Information System (INIS)

    Perring, J.K.; Skyrme, T.H.R.

    1994-01-01

    The classical solutions of a unified field theory in a two-dimensional space-time are considered. This system, a model of a interacting mesons and baryons, illustrates how the particle can be built from a wave-packet of mesons and how reciprocally the meson appears as a tightly bound combination of particle and antiparticle. (author). 6 refs

  17. Aspects of extra dimensional supersymmetric unified theories

    International Nuclear Information System (INIS)

    Fichet, S.

    2011-09-01

    The purpose of this work is to investigate Grand Unified Theories (GUTs) and to make the link with passed and upcoming experiments. The structure of this thesis is as follows. In the first chapter, we will briefly review the sequence of arguments leading to the Higgs mechanism, then to the different concepts underlying physics beyond the Standard Model, and to the paradigm of extra dimensional supersymmetric grand unified theories. At each level of the argumentation, we will mention the different solutions available. The second chapter introduces more formally supersymmetry and extra dimensions, focusing in particular on the aspects of symmetry breaking. Then, in the third chapter, we present in details the two frameworks of extra dimensional theories in which we worked, called supersymmetric gauge-Higgs unification (GHU) and holographic grand unification (HGU) as well as the developments and modifications we brought to them. The fourth chapter is devoted to the low energy viability of the GHU framework, as well as its phenomenological implications. The fifth chapter presents a more generic study of the property of GUT-scale degenerate Higgs mass matrix, common to both frameworks. Finally, the sixth chapter is devoted to the viability and phenomenological implications of the HGU framework, with special emphasis on lepton flavour violation. This quantitative study takes properly into account effects of matrix anarchy, as well as exact flavour observables. The results obtained should generalize, at least qualitatively, to any other model with similar localization and supersymmetry breaking features

  18. ¿Teología para agnósticos?

    Directory of Open Access Journals (Sweden)

    Sotelo Martínez, Igancio

    2002-04-01

    Full Text Available Not available

    Pretendo exponer de la manera más breve unas pocas razones que muestren que la teología concierne también al agnóstico. Por teología entiendo la reflexión sistemática en torno a la fe cristiana y por agnóstico, también en sentido muy amplio, aquel que no participa de esta fe. La tesis que defiendo es que no es necesaria la fe para interesarse por la teología; tiene sentido ocuparse de Dios sin creer en su existencia.
    ¿Por qué el agnóstico habría de ocuparse de la teología cuando el creyente parece que no la necesita? Cree antes de examinar reflexivamente su fe, que no depende de argumentos ni de demostraciones. Lo cierto es que la teología no conduce a la fe y hasta puede dudarse de si la fortalece. Conozco personas profundamente creyentes que huyen de las disquisiciones teológicas como de la peste. Viven la fe en una experiencia de amor al prójimoque no precisa de argumentos. Les basta acompañarse con las Sagradas Escrituras y de algunos libros piadosos o de espiritualidad. Cabría ampliar el horizonte de este artículo y preguntarse por el alcance y sentido que tenga la «reflexión sistemática» sobre Dios para aquellos que creen.
    En todo caso, no deja de ser paradójico intentar una defensa de la teología, cuando parece que les sobra, tanto a agnósticos como a creyentes; incluso la Iglesia ha encerrado a los teólogos en un gueto en el que, si bien gozan de mucha mayor libertad que en el pasado, la disfrutan en buena parte porque se han quedado sin audiencia. Escriben exclusivamente para los colegas que son los únicos que los leen. Claro que, dada la fragmentación actual de los saberes, lo mismo les ocurre a los demás especialistas.
    Si una buena parte de los creyentes se desentienden de la teología, ¿por qué habría de ocupar al agnóstico? Barrunto que una vindicación de la teología valga tanto para los unos como para los otros, pero en esta ocasión considero tan sólo las

  19. The first 62 AGN observed with SDSS-IV MaNGA - II: resolved stellar populations

    Science.gov (United States)

    Mallmann, Nícolas Dullius; Riffel, Rogério; Storchi-Bergmann, Thaisa; Barboza Rembold, Sandro; Riffel, Rogemar A.; Schimoia, Jaderson; da Costa, Luiz Nicolaci; Ávila-Reese, Vladimir; Sanchez, Sebastian F.; Machado, Alice D.; Cirolini, Rafael; Ilha, Gabriele S.; do Nascimento, Janaína C.

    2018-05-01

    We present spatially resolved stellar population age maps, average radial profiles and gradients for the first 62 Active Galactic Nuclei (AGN) observed with SDSS-IV MaNGA to study the effects of the active nuclei on the star formation history of the host galaxies. These results, derived using the STARLIGHT code, are compared with a control sample of non-active galaxies matching the properties of the AGN hosts. We find that the fraction of young stellar populations (SP) in high-luminosity AGN is higher in the inner (R≤0.5 Re) regions when compared with the control sample; low-luminosity AGN, on the other hand, present very similar fractions of young stars to the control sample hosts for the entire studied range (1 Re). The fraction of intermediate age SP of the AGN hosts increases outwards, with a clear enhancement when compared with the control sample. The inner region of the galaxies (AGN and control galaxies) presents a dominant old SP, whose fraction decreases outwards. We also compare our results (differences between AGN and control galaxies) for the early and late-type hosts and find no significant differences. In summary, our results suggest that the most luminous AGN seems to have been triggered by a recent supply of gas that has also triggered recent star formation (t ≤ 40 Myrs) in the central region.

  20. UNRAVELLING THE COMPLEX STRUCTURE OF AGN-DRIVEN OUTFLOWS. II. PHOTOIONIZATION AND ENERGETICS

    Energy Technology Data Exchange (ETDEWEB)

    Karouzos, Marios; Woo, Jong-Hak [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Bae, Hyun-Jin, E-mail: woo@astro.snu.ac.kr [Department of Astronomy and Center for Galaxy EVolution Research, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2016-12-20

    Outflows have been shown to be prevalent in galaxies hosting luminous active galactic nuclei (AGNs); they present a physically plausible way to couple the AGN energy output with the interstellar medium of their hosts. Despite their prevalence, accurate characterization of these outflows has been challenging. In the second of a series of papers, we use Gemini Multi-Object Spectrograph integral field unit (IFU) data of six local ( z  < 0.1) and moderate-luminosity Type 2 AGNs to study the ionization properties and energetics of AGN-driven outflows. We find strong evidence connecting the extreme kinematics of the ionized gas to the AGN photoionization. The kinematic component related to the AGN-driven outflow is clearly separated from other kinematic components, such as virial motions or rotation, on the velocity and velocity dispersion diagram. Our spatially resolved kinematic analysis reveals that 30 to 90% of the total mass and kinetic energy of the outflow is contained within the central kpc of the galaxy. The spatially integrated mass and kinetic energy of the gas entrained in the outflow correlate well with the AGN bolometric luminosity and results in energy conversion efficiencies between 0.01% and 1%. Intriguingly, we detect ubiquitous signs of ongoing circumnuclear star formation. Their small size, the centrally contained mass and energy, and the universally detected circumnuclear star formation cast doubts on the potency of these AGN-driven outflows as agents of galaxy-scale negative feedback.

  1. Outflow Kinematics Manifested by the Hα Line: Gas Outflows in Type 2 AGNs. IV

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Daeun; Woo, Jong-Hak; Bae, Hyun-Jin, E-mail: woo@astro.snu.ac.kr [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2017-08-20

    Energetic ionized gas outflows driven by active galactic nuclei (AGNs) have been studied as a key phenomenon related to AGN feedback. To probe the kinematics of the gas in the narrow-line region, [O iii] λ 5007 has been utilized in a number of studies showing nonvirial kinematic properties due to AGN outflows. In this paper, we statistically investigate whether the H α emission line is influenced by AGN-driven outflows by measuring the kinematic properties based on the H α line profile and comparing them with those of [O iii]. Using the spatially integrated spectra of ∼37,000 Type 2 AGNs at z < 0.3 selected from the Sloan Digital Sky Survey DR7, we find a nonlinear correlation between H α velocity dispersion and stellar velocity dispersion that reveals the presence of the nongravitational component, especially for AGNs with a wing component in H α . The large H α velocity dispersion and velocity shift of luminous AGNs are clear evidence of AGN outflow impacts on hydrogen gas, while relatively smaller kinematic properties compared to those of [O iii] imply that the observed outflow effect on the H α line is weaker than the case of [O iii].

  2. Hurricane Agnes rainfall and floods, June-July 1972

    Science.gov (United States)

    Bailey, James F.; Patterson, James Lee; Paulhus, Joseph Louis Hornore

    1975-01-01

    Hurricane Agnes originated in the Caribbean Sea region in mid-June. Circulation barely reached hurricane intensity for a brief period in the Gulf of Mexico. The storm crossed the Florida Panhandle coastline on June 19, 1972, and followed an unusually extended overland trajectory combining with an extratropical system to bring very heavy rain from the Carolinas northward to New York. This torrential rain followed the abnormally wet May weather in the Middle Atlantic States and set the stage for the subsequent major flooding. The record-breaking floods occurred in the Middle Atlantic States in late June and early July 1972. Many streams in the affected area experienced peak discharges several times the previous maxima of record. Estimated recurrence intervals of peak flows at many gaging stations on major rivers and their tributaries exceeded 100 years. The suspended-sediment concentration and load of most flooded streams were also unusually high. The widespread flooding from this storm caused Agnes to be called the most destructive hurricane in United States history, claiming 117 lives and causing damage estimated at $3.1 billion in 12 States. Damage was particularly high in New York, Pennsylvania, Maryland, and Virginia. The detailed life history of Hurricane Agnes, including the tropical depression and tropical storm stages, is traced. Associated rainfalls are analyzed and compared with climatologic recurrence values. These are followed by a detailed description of the flood and streamflows of each affected basin. A summary of peak stages and discharges and comparison data for previous floods at 989 stations are presented. Deaths and flood damage estimates are compiled.

  3. Investigating the Temperature Problem in Narrow Line Emitting AGN

    Science.gov (United States)

    Jenkins, Sam; Richardson, Chris T.

    2018-06-01

    Our research investigates the physical conditions in gas clouds around the narrow line region of AGN. Specifically, we explore the necessary conditions for anomalously high electron temperatures, Te, in those clouds. Our 321 galaxy data set was acquired from SDSS DR14 after requiring S/N > 5.0 in [OIII] 4363 and S/N > 3.0 in all BPT diagram emission lines, to ensure both accurate Te and galaxy classification, with 0.04 study the effects these conditions have on gas cloud Te.

  4. Interstellar Scintillation and Scattering of Micro-arc-second AGN

    Directory of Open Access Journals (Sweden)

    David L. Jauncey

    2016-11-01

    Full Text Available The discovery of the first quasar 3C 273 led directly to the discovery of their variability at optical and radio wavelengths. We review the radio variability observations, in particular the variability found at frequencies below 1 GHz, as well as those exhibiting intra-day variability (IDV at cm wavelengths. Observations have shown that IDV arises principally from scintillation caused by scattering in the ionized interstellar medium of our Galaxy. The sensitivity of interstellar scintillation towards source angular sizes has provided a powerful tool for studying the most compact components of radio-loud AGN at microarcsecond and milliarcsecond scale resolution.

  5. Hot Coronae in Local AGN: Present Status and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Andrea Marinucci

    2018-04-01

    Full Text Available The nuclear X-ray emission in radio-quiet Active Galactic Nuclei (AGN is commonly believed to be due to inverse Compton scattering of soft UV photons in a hot corona. The radiation is expected to be polarized, the polarization degree depending mainly on the geometry and optical depth of the corona. Nuclear Spectroscopic Telescope Array (NuSTAR observations are providing for the first time high quality measurements of the coronal physical parameters—temperature and optical depth. We hereby review the NuSTAR results on the coronal physical parameters (temperature and optical depth and discuss their implications for future X-ray polarimetric studies.

  6. The jet of the Low Luminosity AGN of M81

    Directory of Open Access Journals (Sweden)

    Alberdi A.

    2013-12-01

    Full Text Available In this contribution, we summarize our main results of a big campaign of global VLBI observations of the AGN in M81 (M81* phase-referenced to the radio supernova SN 1993J. Thanks to the precise multi-epoch and multi-frequency astrometry, we have determined the normalized core-shift of the relativistic jet of M81* and estimated both the magnetic field and the particle density at the jet base. We have also found evidence of jet precession in M81* coming from the systematic time evolution of the jet orientation correlated with changes in the overall flux density.

  7. Unified theory of effective interaction

    Energy Technology Data Exchange (ETDEWEB)

    Takayanagi, Kazuo, E-mail: k-takaya@sophia.ac.jp

    2016-09-15

    We present a unified description of effective interaction theories in both algebraic and graphic representations. In our previous work, we have presented the Rayleigh–Schrödinger and Bloch perturbation theories in a unified fashion by introducing the main frame expansion of the effective interaction. In this work, we start also from the main frame expansion, and present various nonperturbative theories in a coherent manner, which include generalizations of the Brandow, Brillouin–Wigner, and Bloch–Horowitz theories on the formal side, and the extended Krenciglowa–Kuo and the extended Lee–Suzuki methods on the practical side. We thus establish a coherent and comprehensive description of both perturbative and nonperturbative theories on the basis of the main frame expansion.

  8. Split supersymmetry in unified models

    International Nuclear Information System (INIS)

    Dutta, Bhaskar; Mimura, Yukihiro

    2005-01-01

    In the context of split supersymmetry, the gaugino mass spectrum seems to be very important to satisfy the dark matter content of the universe and the gauge coupling unification. In this Letter, we have considered various sources of gaugino masses in the context of unified models. We show that the gaugino mass spectrum varies in different unification pictures. In the context of SU(5), we have found that the bino/wino mass ratio can be close to one at the weak scale which is helpful to satisfy the WMAP data. The gluino/wino mass ratio is also different from the usual scenario of unified gaugino masses. The gaugino masses can be around one TeV and m SUSY is chosen so that the gluino mass does not create any cosmological problem. In the context of the Pati-Salam model, we show that the gluino mass can be made very heavy even after maintaining the unification of the gauge couplings

  9. Monitoring AGNs with Hbeta Asymmetry with the Wyoming Infra-Red Observatory

    Science.gov (United States)

    Brotherton, Michael S.; Du, Pu; Wang, Jian-Min; Wang, Kai; Huang, Zhengpeng; Hu, Chen; Li, Yan-rong; Kasper, David H.; Chick, William T.; Nguyen, My L.; Maithil, Jaya; Hand, Derek; Bai, Jin-Ming; Ho, Luis

    2018-06-01

    We present preliminary results from two seasons of reverberation mapping of AGNs using the optical longslit spectrograph on the 2.3 meter WIRO telescope. The majority of the sample is part of our "Monitoring AGNs with Hbeta Asymmetry" project, also known as MAHA, which targets rarer AGNs with extremely asymmetric profiles that may provide new insights into the full diversity of size and structure of the broad-line region (BLR). Our hundreds of nights of telescope time provide dozens of epochs of spectra for approximately two dozen objects. Notably we find that many AGNs with broader asymmetric Hbeta emission lines possess time lags significantly shorter than expected for their luminosity in comparison to the majority of AGNs reverberation mapped.

  10. Towards A Complete Census of the Compton-thick AGN Population in our Cosmic Backyard

    Science.gov (United States)

    Annuar, Ady

    2016-09-01

    We propose for Chandra and NuSTAR observations of two local AGNs to characterise their obscuring properties. We are using Chandra and NuSTAR to form the first complete measurement of the column density (N_H) distribution of AGN at D35%. We also found that Chandra resolution is key in resolving the AGN from off-nuclear X-ray sources. When combined with NuSTAR, this allow us to accurately characterise the broadband spectrum of the AGN, and identify it as CT. These new observations will provide Chandra data for all D<15Mpc AGNs and boost up the N_H distribution up to 85% complete. This will be fully completed with future NuSTAR observations.

  11. Unified theory of the nucleus

    International Nuclear Information System (INIS)

    Wildermuth, K.; Tang, Y.C.

    1977-01-01

    The purpose of this monograph is to describe a microscopic nuclear theory which can be used to consider all low-energy nuclear phenomena from a unified viewpoint. In this theory, the Pauli principle is completely taken into account and translationally invariant wave functions are always employed. It can be utilized to study reactions initiated not only by nucleons but also by arbitrary composite particles

  12. A unified grand tour of theoretical physics

    CERN Document Server

    Lawrie, Ian D

    2013-01-01

    A Unified Grand Tour of Theoretical Physics invites its readers to a guided exploration of the theoretical ideas that shape our contemporary understanding of the physical world at the fundamental level. Its central themes, comprising space-time geometry and the general relativistic account of gravity, quantum field theory and the gauge theories of fundamental forces, and statistical mechanics and the theory of phase transitions, are developed in explicit mathematical detail, with an emphasis on conceptual understanding. Straightforward treatments of the standard models of particle physics and cosmology are supplemented with introductory accounts of more speculative theories, including supersymmetry and string theory. This third edition of the Tour includes a new chapter on quantum gravity, focusing on the approach known as Loop Quantum Gravity, while new sections provide extended discussions of topics that have become prominent in recent years, such as the Higgs boson, massive neutrinos, cosmological perturba...

  13. Cosmological implications of grand unified theories

    International Nuclear Information System (INIS)

    Nanopoulos, D.V.

    1982-01-01

    These lectures, mainly devoted to the cosmological implications of GUTs, also include the essential ingredients of GUTs and some of their important applications to particle physics. Section 1 contains some basic points concerning the structure of the standard strong and electroweak interactions prior to grand unification. A detailed expose of GUTs is attempted in sect. 2, including their basci principles and their consequences for particle physics. The minimal, simplest GUT, SU 5 is analysed in some detail and it will be used throughout these lectures as the GUT prototype. Finally, sect. 3 contains the most important cosmological implications of GUTs, including baryon number generation in the early Universe (in rather lengthy detail), dissipative processes in the very early Universe, grand unified monopoles, etc. (orig./HSI)

  14. Grand unified models including extra Z bosons

    International Nuclear Information System (INIS)

    Li Tiezhong

    1989-01-01

    The grand unified theories (GUT) of the simple Lie groups including extra Z bosons are discussed. Under authors's hypothesis there are only SU 5+m SO 6+4n and E 6 groups. The general discussion of SU 5+m is given, then the SU 6 and SU 7 are considered. In SU 6 the 15+6 * +6 * fermion representations are used, which are not same as others in fermion content, Yukawa coupling and broken scales. A conception of clans of particles, which are not families, is suggested. These clans consist of extra Z bosons and the corresponding fermions of the scale. The all of fermions in the clans are down quarks except for the standard model which consists of Z bosons and 15 fermions, therefore, the spectrum of the hadrons which are composed of these down quarks are different from hadrons at present

  15. Towards A Complete Census of the Compton-thick AGN population and the NH Distribution of AGN in the Local Universe.

    Science.gov (United States)

    Annuar, A.

    2015-09-01

    We present updated results from an ongoing project to establish the most unbiased census of the Compton- thick active galactic nucleus (CTAGN) population and the intrinsic column density (NH) distribution of the overall AGN population in the local universe, using a sample of mid-infrared (mid-IR) selected AGN within 15 Mpc. We find that 20% of the AGN in the sample are bona-fide CTAGN based upon hard X-ray studies (E > 10 keV). More candidates are then selected using multiwavelength techniques, i.e. mid-IR:X-ray and optical [OIII]5007:X-ray flux ratios. Based on these analyses along with evidence from previous literature, we initially find a further 25% of potential candidates. We then observed two of these candidates, NGC 5643 and NGC 3486, using NuSTAR and is able to confirm the former as a CTAGN and rule out the latter as an obscured AGN. This constrains the total CTAGN population in the sample to 25-40%, though it could potentially be as high as 65% accounting for those that still lack data. Finally, we use these results to estimate the intrinsic NH distribution of the local AGN population. Two more of our CTAGN candidates are scheduled to be observed by NuSTAR, bringing the completeness of hard X-ray energy data of the sample to 65%. This work provides a well-defined local benchmark for AGN unification studies.

  16. PRIMUS: INFRARED AND X-RAY AGN SELECTION TECHNIQUES AT 0.2 < z < 1.2

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, Alexander J.; Coil, Alison L.; Aird, James; Diamond-Stanic, Aleksandar M. [Center for Astrophysics and Space Sciences, Department of Physics, University of California, 9500 Gilman Dr., La Jolla, San Diego, CA 92093 (United States); Moustakas, John [Department of Physics and Astronomy, Siena College, 515 Loudon Road, Loudonville, NY 12211 (United States); Blanton, Michael R. [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Cool, Richard J. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Eisenstein, Daniel J. [Harvard College Observatory, 60 Garden St., Cambridge, MA 02138 (United States); Wong, Kenneth C. [Steward Observatory, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 (United States); Zhu Guangtun [Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 (United States)

    2013-06-10

    We present a study of Spitzer/IRAC and X-ray active galactic nucleus (AGN) selection techniques in order to quantify the overlap, uniqueness, contamination, and completeness of each. We investigate how the overlap and possible contamination of the samples depend on the depth of both the IR and X-ray data. We use Spitzer/IRAC imaging, Chandra and XMM-Newton X-ray imaging, and spectroscopic redshifts from the PRism MUlti-object Survey to construct galaxy and AGN samples at 0.2 < z < 1.2 over 8 deg{sup 2}. We construct samples over a wide range of IRAC flux limits (SWIRE to GOODS depth) and X-ray flux limits (10 ks to 2 Ms). We compare IR-AGN samples defined using both the IRAC color selection of Stern et al. and Donley et al. with X-ray-detected AGN samples. For roughly similar depth IR and X-ray surveys, we find that {approx}75% of IR-selected AGNs are also identified as X-ray AGNs. This fraction increases to {approx}90% when comparing against the deepest X-ray data, indicating that at most {approx}10% of IR-selected AGNs may be heavily obscured. The IR-AGN selection proposed by Stern et al. suffers from contamination by star-forming galaxies at various redshifts when using deeper IR data, though the selection technique works well for shallow IR data. While similar overall, the IR-AGN samples preferentially contain more luminous AGNs, while the X-ray AGN samples identify a wider range of AGN accretion rates including low specific accretion rate AGNs, where the host galaxy light dominates at IR wavelengths. The host galaxy populations of the IR and X-ray AGN samples have similar rest-frame colors and stellar masses; both selections identify AGNs in blue, star-forming and red, quiescent galaxies.

  17. The mm-wave compact component of AGN

    Science.gov (United States)

    Behar, Ehud; Vogel, Stuart; Baldi, Ranieri D.; Smith, Krista L.; Mushotzky, Richard F.

    2018-05-01

    mm-wave emission from Active Galactic Nuclei (AGN) may hold the key to understanding the physical origin of their radio cores. The correlation between radio/mm and X-ray luminosity may suggest a similar physical origin of the two sources. Since synchrotron self absorption decreases with frequency, mm-waves probe smaller length scales than cm-waves. We report on 100 GHz (3 mm) observations with CARMA of 26 AGNs selected from the hard X-ray Swift/BAT survey. 20/26 targets were detected at 100 GHz down to the 1 mJy (3σ) sensitivity, which corresponds to optically thick synchrotron source sizes of 10-4 - 10-3 pc. Most sources show a 100 GHz flux excess with respect to the spectral slope extrapolated from low frequencies. This mm spectral component likely originates from smaller scales than the few-GHz emission. The measured mm sources lie roughly around the Lmm (100 GHz) ˜10-4LX (2-10 keV) relation, similar to a few previously published X-ray selected sources, and hinting perhaps at a common coronal origin.

  18. Testing the AGN Unification Model in the Infrared

    International Nuclear Information System (INIS)

    Ramos Almeida, C; Levenson, N A; Radomski, J T; Alonso-Herrero, A; Asensio Ramos, A; Rodríguez Espinosa, J M; Pérez García, A M; Packham, C; Mason, R; Díaz-Santos, T

    2012-01-01

    We present near-to-mid-infrared spectral energy distributions (SEDs) for 21 Seyfert galaxies, using subarcsecond resolution imaging data. Our aim is to compare the properties Seyfert 1 (Sy1) and Seyfert 2 (Sy2) tori using clumpy torus models and a Bayesian approach to fit the infrared (IR) nuclear SEDs. These dusty tori have physical sizes smaller than 6 pc radius, as derived from our fits. Active galactic nuclei (AGN) unification schemes account for a variety of observational differences in terms of viewing geometry. However, we find evidence that strong unification may not hold, and that the immediate dusty surroundings of Sy1 and Sy2 nuclei are intrinsically different. The Type 2 tori studied here are broader, have more clumps, and these clumps have lower optical depths than those of Type 1 tori. The larger the covering factor of the torus, the smaller the probability of having direct view of the AGN, and vice-versa. In our sample, Sy2 tori have larger covering factors (C T = 0.95±0.02) and smaller escape probabilities than those of Sy1 (C T = 0.5±0.1). Thus, on the basis of the results presented here, the classification of a Seyfert galaxy may depend more on the intrinsic properties of the torus rather than on its mere inclination, in contradiction with the simplest unification model.

  19. The broad-band SEDs of four `hypervariable' AGN

    Science.gov (United States)

    Collinson, James S.; Ward, Martin J.; Lawrence, Andy; Bruce, Alastair; MacLeod, Chelsea L.; Elvis, Martin; Gezari, Suvi; Marshall, Philip J.; Done, Chris

    2018-03-01

    We present an optical-to-X-ray spectral analysis of four `hypervariable' AGN (HVAs) discovered by comparing Pan-STARRS data to that from the Sloan Digital Sky Survey over a 10 yr baseline (Lawrence et al.). There is some evidence that these objects are X-ray loud for their corresponding UV luminosities, but given that we measured them in a historic high state, it is not clear whether to take the high state or low state as typical of the properties of these HVAs. We estimate black hole masses based on Mg II and H α emission line profiles, and either the high- or low-state luminosities, finding mass ranges log (MBH/M⊙) = 8.2-8.8 and log (MBH/M⊙) = 7.9-8.3, respectively. We then fit energy-conserving models to the spectral energy distributions (SEDs), obtaining strong constraints on the bolometric luminosity and αOX. We compare the SED properties with a larger, X-ray selected AGN sample for both of these scenarios, and observe distinct groupings in spectral shape versus luminosity parameter space. In general, the SED properties are closer to normal if we assume that the low state is representative. This supports the idea that the large slow outbursts may be due to extrinsic effects (for example microlensing) as opposed to accretion rate changes, but a larger sample of HVAs is needed to be confident of this conclusion.

  20. Evidence for AGN feedback in low-mass galaxies

    Science.gov (United States)

    Masters, Karen; Penny, Sam; Smethurst, Rebecca; Krawczyk, Coleman; Nichol, Bob; SDSS-IV MaNGA

    2018-01-01

    Despite being the dominant galaxy population by number in groups and clusters, the formation and quenching mechanism of dwarf galaxies remains unknown. We present evidence for AGN feedback in a subset of 69 quenched low-mass galaxies (M* less than 5e9 Msun, fainter than Mr = -19) selected from the first two years of the MaNGA survey. The majority (85 per cent) of these quenched galaxies appear to reside in a group environment. We find 6 galaxies in our sample that appear to have an active AGN that is preventing on-going star-formation; this is the first time such a feedback mechanism has been observed in this mass range. Interestingly, five of these six galaxies have an ionised gas component that is kinematically offset from their stellar component, suggesting the gas is either recently accreted or outflowing. We hypothesise these six galaxies are low-mass equivalents to the “red geysers” observed in more massive galaxies. Of the other 62 galaxies in the sample, we find 8 do appear to have some low-level, residual star formation, or emission from hot, evolved stars. The remaining galaxies in our sample have no detectable ionised gas emission throughout their structures, consistent with them being quenched. I will show that despite being the "simplest" galaxies in our current models of galaxy formation, these quenched dwarf galaxies are a diverse population.

  1. The cosmic evolution of massive black holes in the Horizon-AGN simulation

    Science.gov (United States)

    Volonteri, M.; Dubois, Y.; Pichon, C.; Devriendt, J.

    2016-08-01

    We analyse the demographics of black holes (BHs) in the large-volume cosmological hydrodynamical simulation Horizon-AGN. This simulation statistically models how much gas is accreted on to BHs, traces the energy deposited into their environment and, consequently, the back-reaction of the ambient medium on BH growth. The synthetic BHs reproduce a variety of observational constraints such as the redshift evolution of the BH mass density and the mass function. Strong self-regulation via AGN feedback, weak supernova feedback, and unresolved internal processes result in a tight BH-galaxy mass correlation. Starting at z ˜ 2, tidal stripping creates a small population of BHs over-massive with respect to the halo. The fraction of galaxies hosting a central BH or an AGN increases with stellar mass. The AGN fraction agrees better with multi-wavelength studies, than single-wavelength ones, unless obscuration is taken into account. The most massive haloes present BH multiplicity, with additional BHs gained by ongoing or past mergers. In some cases, both a central and an off-centre AGN shine concurrently, producing a dual AGN. This dual AGN population dwindles with decreasing redshift, as found in observations. Specific accretion rate and Eddington ratio distributions are in good agreement with observational estimates. The BH population is dominated in turn by fast, slow, and very slow accretors, with transitions occurring at z = 3 and z = 2, respectively.

  2. A MODEL FOR TYPE 2 CORONAL LINE FOREST (CLiF) AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Glidden, Ana [Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Rose, Marvin; Elvis, Martin; McDowell, Jonathan [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2016-06-10

    We present a model for the classification of Coronal Line Forest Active Galactic Nuclei (CLiF AGNs). CLiF AGNs are of special interest due to their remarkably large number of emission lines, especially forbidden high-ionization lines (FHILs). Rose et al. suggest that their emission is dominated by reflection from the inner wall of the obscuring region rather than direct emission from the accretion disk. This makes CLiF AGNs laboratories to test AGN-torus models. Modeling an AGN as an accreting supermassive black hole surrounded by a cylinder of dust and gas, we show a relationship between the viewing angle and the revealed area of the inner wall. From the revealed area, we can determine the amount of FHIL emission at various angles. We calculate the strength of [Fe vii] λ 6087 emission for a number of intermediate angles (30°, 40°, and 50°) and compare the results with the luminosity of the observed emission line from six known CLiF AGNs. We find that there is good agreement between our model and the observational results. The model also enables us to determine the relationship between the type 2:type 1 AGN fraction vs the ratio of torus height to radius, h / r .

  3. Low-energy neutral current phenomenology and grand unified theories

    International Nuclear Information System (INIS)

    Del Aguila, F.; Mendez, A.

    1981-01-01

    We derive necessary and sufficient conditions to be satisfied by any expanded electroweak gauge model in order to reproduce the standard model low-energy neutral current predictions. These conditions imply several constraints on the neutral gauge boson masses and the quantum number assignments for the ordinary fermions. Using these conditions, we prove that the popular grand unified theories based on the gauge groups SO(10) and E6 can only accommodate trivial extensions of the standard model. As a consequence, if any of these grand unified models works at some energy scale, present low-energy neutral current phenomenology implies that the Z-boson must be produced with the expected mass and couplings to the ordinary fermions. Any additional neutral gauge boson (with the possible exception of very heavy ones) could only be produced in hadronic collisions and it would not decay in e + e - . (orig.)

  4. Unified approach to dense matter

    International Nuclear Information System (INIS)

    Park, Byung-Yoon; Lee, Hee-Jung; Vento, Vicente; Kim, Joon-Il; Min, Dong-Pil; Rho, Mannque

    2005-01-01

    We apply the Skyrme model to dense hadronic matter, which provides a unified approach to high density, valid in the large N c limit. In our picture, dense hadronic matter is described by the classical soliton configuration with minimum energy for the given baryon number density. By incorporating the meson fluctuations on such ground state we obtain an effective Lagrangian for meson dynamics in a dense medium. Our starting point has been the Skyrme model defined in terms of pions, thereafter we have extended and improved the model by incorporating other degrees of freedom such as dilaton, kaons and vector mesons

  5. Einstein's theory of unified fields

    CERN Document Server

    Tonnelat, Marie Antoinette

    2014-01-01

    First published in1966, here is presented a comprehensive overview of one of the most elusive scientific speculations by the pre-eminent genius of the 20th century. The theory is viewed by some scientists with deep suspicion, by others with optimism, but all agree that it represents an extreme challenge. As the author herself affirms, this work is not intended to be a complete treatise or 'didactic exposition' of the theory of unified fields, but rather a tool for further study, both by students and professional physicists. Dealing with all the major areas of research whic

  6. Morphology of AGN Emission Line Regions in SDSS-IV MaNGA Survey

    Science.gov (United States)

    He, Zhicheng; Sun, Ai-Lei; Zakamska, Nadia L.; Wylezalek, Dominika; Kelly, Michael; Greene, Jenny E.; Rembold, Sandro B.; Riffel, Rogério; Riffel, Rogemar A.

    2018-05-01

    Extended narrow-line regions (NLRs) around active galactic nuclei (AGN) are shaped by the distribution of gas in the host galaxy and by the geometry of the circumnuclear obscuration, and thus they can be used to test the AGN unification model. In this work, we quantify the morphologies of the narrow-line regions in 308 nearby AGNs (z = 0 - 0.14, Lbol˜1042.4 - 44.1 erg s-1) from the MaNGA survey. Based on the narrow-line region maps, we find that a large fraction (81%) of these AGN have bi-conical NLR morphology. The distribution of their measured opening angles suggests that the intrinsic opening angles of the ionization cones has a mean value of 85-98° with a finite spread of 39-44° (1-σ). Our inferred opening angle distribution implies a number ratio of type I to type II AGN of 1:1.6-2.3, consistent with other measurements of the type I / type II ratio at low AGN luminosities. Combining these measurements with the WISE photometry data, we find that redder mid-IR color (lower effective temperature of dust) corresponds to stronger and narrower photo-ionized bicones. This relation is in agreement with the unification model that suggests that the bi-conical narrow-line regions are shaped by a toroidal dusty structure within a few pc from the AGN. Furthermore, we find a significant alignment between the minor axis of host galaxy disks and AGN ionization cones. Together, these findings suggest that obscuration on both circumnuclear (˜pc) and galactic (˜ kpc) scales are important in shaping and orienting the AGN narrow-line regions.

  7. Unified Facilities Criteria (UFC) Design Guide. Army Reserve Facilities

    Science.gov (United States)

    2010-02-01

    horticulturally appropriate to the site specific location in which they are planted. Consideration should be given to adjacent structures and improvements...impact FPI Federal Prison Industries FPM Feet per minute GFCI Government-furnished/contractor-installed or Ground-Fault Circuit Interrupter GFGI...Uniform Federal Accessibility Standards UFGs Unified Facility Guide Specifications UFGs Rst UFGS - Reserve Support Team UnICoR Federal Prison Industry

  8. Wartime Roles and Capabilities for the Unified Logistic Staffs

    Science.gov (United States)

    1989-02-01

    standard Army ammunition system SAPO Subarea Petroleum Office SCP service control point (fuels) SHAPE Supreme Headquarters, Allied Powers Europe SIDATH... SAPOs ). Communication exists between the operations and logistic staffs within the unified, component, Service, and JS levels. But between...daily. The JPOs/ SAPOs receive the short-term requirements and consoli- date them for resupply by submitting slates (how much, when, and where needed

  9. Fossil shell emission in dying radio loud AGNs

    Science.gov (United States)

    Kino, M.; Ito, H.; Kawakatu, N.; Orienti, M.; Nagai, H.; Wajima, K.; Itoh, R.

    2016-02-01

    We investigate shell emission associated with dying radio loud AGNs. First, based on our recent work by Ito et al. (2015), we describe the dynamical and spectral evolution of shells after stopping the jet energy injection. We find that the shell emission overwhelms that of the radio lobes soon after stopping the jet energy injection because fresh electrons are continuously supplied into the shell via the forward shock, while the radio lobes rapidly fade out without jet energy injection. We find that such fossil shells can be a new class of target sources for SKA telescope. Next, we apply the model to the nearby radio source 3C84. Then, we find that the fossil shell emission in 3C84 is less luminous in the radio band while it is bright in the TeV γ-ray band and can be detectable by CTA. Data from STELLA

  10. Tracing the External Origin of the AGN Gas Fueling Reservoir

    Directory of Open Access Journals (Sweden)

    Sandra I. Raimundo

    2018-01-01

    Full Text Available Near-infrared observations of the active galaxy MCG–6-30-15 provide strong evidence that its molecular gas fueling reservoir is of external origin. MCG–6-30-15 has a counter-rotating core of stars within its central 400 pc and a counter-rotating disc of molecular gas that extends as close as ~50–100 pc from the central black hole. The gas counter-rotation establishes that the gas reservoir in the center of the galaxy originates from a past external accretion event. In this contribution we discuss the gas and stellar properties of MCG–6-30-15, its past history and how the findings on this galaxy can be used to understand AGN fueling in S0 galaxies with counter-rotating structures.

  11. Safety reassessment of the Paks NPP (the AGNES project)

    Energy Technology Data Exchange (ETDEWEB)

    Gado, J [Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics; Bajsz, J; Cserhati, A; Elter, J [Paksi Atomeroemue Vallalat, Paks (Hungary); Hollo, E [Energiagazdalkodasi Intezet, Budapest (Hungary); Kovacs, K [EROTERV Engineering and Contractor Co (Hungary); Maroti, L [Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics; Miko, S [Paksi Atomeroemue Vallalat, Paks (Hungary); Techy, Z [Energiagazdalkodasi Intezet, Budapest (Hungary); Vidovszky, I [Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics

    1996-12-31

    The reassessment of the Paks NPP safety according to internationally recognized criteria of the Advanced General and New Evaluation of Safety (AGNES) project is outlined. The Paks NPP consists of four WWER-440/V-213 units. The following groups of analysis have been performed: system analysis and description; analysis of design basis accidents; severe accidents analysis; level 1 probabilistic safety analysis. Postulated accidents (PA) and Anticipated Operational Occurrences (AOO) are estimated in detail for the following initiating events: increase/decrease in secondary heat removal; decrease in primary coolant inventory; increase/decrease of reactor coolant inventory; reactivity and power distribution anomalies; analysis of transients with the failure of reactor scram (ATWS); pressurized thermal shock analyses. Severe accident analysis was made for the accidents on in-vessel phase and containment phase, for radioactive release and for accident management.

  12. Statistical Analysis of the Microvariable AGN Source Mrk 501

    Directory of Open Access Journals (Sweden)

    Alberto C. Sadun

    2018-02-01

    Full Text Available We report on the optical observations and analysis of the high-energy peaked BL Lac object (HBL, Mrk 501, at redshift z = 0.033. We can confirm microvariable behavior over the course of minutes on several occasions per night. As an alternative to the commonly understood dynamical model of random variations in intensity of the AGN, we develop a relativistic beaming model with a minimum of free parameters, which allows us to infer changes in the line of sight angles for the motion of the different relativistic components. We hope our methods can be used in future studies of beamed emission in other active microvariable sources, similar to the one we explored.

  13. Cloudy Skies over AGN: Observations with Simbol-X

    Science.gov (United States)

    Salvati, M.; Risaliti, G.

    2009-05-01

    Recent time-resolved spectroscopic X-ray studies of bright obscured AGN show that column density variability on time scales of hours/days may be common, at least for sources with NH>1023 cm-2. This opens new oppurtunities in the analysis of the structure of the circumnuclear medium and of the X-ray source: resolving the variations due to single clouds covering/uncovering the X-ray source provides tight constraints on the source size, the clouds' size and distance, and their average number, density and column density. We show how Simbol-X will provide a breakthrough in this field, thanks to its broad band coverage, allowing (a) to precisely disentangle the continuum and NH variations, and (2) to extend the NH variability analysis to column densities >1023 cm-2.

  14. Bare AGN: an Unobscured View of the Innermost Accretion Geometry

    Science.gov (United States)

    Fink, M.; Dauser, T.; Beuchert, T.; Jeffreson, S.; Tawabutr, J.; Wilms, J.; Garcia, J.; Walton, D.

    2017-10-01

    In a systematic study of the relativistic reflection spectra and coronal properties for a sample of bare AGN we analyze high signal-to-noise spectra obtained with the XMM-Newton and NuSTAR observatories utilizing state-of-the-art reflection codes. Features of blurred reflection off an ionized accretion disk are modelled using different flavors of the relativistic ray-tracing code Relxill. We show that the more physically motivated and self-consistent lamp-post geometry is largely consistent with fits of broken power-law emissivity profiles. We provide good constraints on parameters describing the compact reprocessing corona, i.e., the reflection fraction and the lamp-post height. The latter are found to be prevalent within 1-10 r_{g}, while our models generally find close-to-maximal black hole spins. These results are discussed and compared with previous studies by Walton et al. (2013).

  15. Linear Polarization Properties of Parsec-Scale AGN Jets

    Directory of Open Access Journals (Sweden)

    Alexander B. Pushkarev

    2017-12-01

    Full Text Available We used 15 GHz multi-epoch Very Long Baseline Array (VLBA polarization sensitive observations of 484 sources within a time interval 1996–2016 from the MOJAVE program, and also from the NRAO data archive. We have analyzed the linear polarization characteristics of the compact core features and regions downstream, and their changes along and across the parsec-scale active galactic nuclei (AGN jets. We detected a significant increase of fractional polarization with distance from the radio core along the jet as well as towards the jet edges. Compared to quasars, BL Lacs have a higher degree of polarization and exhibit more stable electric vector position angles (EVPAs in their core features and a better alignment of the EVPAs with the local jet direction. The latter is accompanied by a higher degree of linear polarization, suggesting that compact bright jet features might be strong transverse shocks, which enhance magnetic field regularity by compression.

  16. Safety reassessment of the Paks NPP (the AGNES project)

    International Nuclear Information System (INIS)

    Gado, J.; Hollo, E.; Kovacs, K.; Maroti, L.; Techy, Z.; Vidovszky, I.

    1995-01-01

    The reassessment of the Paks NPP safety according to internationally recognized criteria of the Advanced General and New Evaluation of Safety (AGNES) project is outlined. The Paks NPP consists of four WWER-440/V-213 units. The following groups of analysis have been performed: system analysis and description; analysis of design basis accidents; severe accidents analysis; level 1 probabilistic safety analysis. Postulated accidents (PA) and Anticipated Operational Occurrences (AOO) are estimated in detail for the following initiating events: increase/decrease in secondary heat removal; decrease in primary coolant inventory; increase/decrease of reactor coolant inventory; reactivity and power distribution anomalies; analysis of transients with the failure of reactor scram (ATWS); pressurized thermal shock analyses. Severe accident analysis was made for the accidents on in-vessel phase and containment phase, for radioactive release and for accident management

  17. Star-forming Galaxies as AGN Imposters? A Theoretical Investigation of the Mid-infrared Colors of AGNs and Extreme Starbursts

    Science.gov (United States)

    Satyapal, Shobita; Abel, Nicholas P.; Secrest, Nathan J.

    2018-05-01

    We conduct for the first time a theoretical investigation of the mid-infrared spectral energy distribution (SED) produced by dust heated by an active galactic nucleus (AGN) and an extreme starburst. These models employ an integrated modeling approach using photoionization and stellar population synthesis models in which both the line and emergent continuum is predicted from gas exposed to the ionizing radiation from a young starburst and an AGN. In this work, we focus on the infrared colors from the Wide-field Infrared Survey Explorer, predicting the dependence of the colors on the input radiation field, the interstellar medium conditions, the obscuring column, and the metallicity. We find that an extreme starburst can mimic an AGN in two band mid-infrared color cuts employed in the literature. However, the three-band color cuts employed in the literature require starbursts with extremely high ionization parameters or gas densities. We show that the extreme mid-infrared colors seen in some blue compact dwarf galaxies are not due to metallicity but rather a combination of high ionization parameters and high column densities. Based on our theoretical calculations, we present a theoretical mid-infrared color cut that will exclude even the most extreme starburst that we have modeled in this work. The theoretical AGN demarcation region presented here can be used to identify elusive AGN candidates for future follow-up studies with the James Webb Space Telescope. The full suite of simulated SEDs are available online.

  18. Development of standards, criteria, specifications. Vol. 2 - Longlife.. Sustainable, energy efficient and resource saving, residential buildings in consideration of unified procedures and new and adapted technologies. Project in the Baltic Sea region programme 2007-2013

    Energy Technology Data Exchange (ETDEWEB)

    Rueckert, Klaus (ed.)

    2010-07-01

    Energy and Cost Efficiency as the key characteristics of the sustainability have been the main consideration of different parts of research represented in the Longlife 2 Report. Longlife 2 Report is in fact the final result of work package 4 ''Developments of Standards and Criteria for Sustainable Building and Construction''. Work package 4 was created based on the work package 3 ''Analysis and comparison of state of technology, administration and legal procedures, financial situation, demographic needs, similarities and differences in the participant countries: Denmark, Germany, Lithuania, Poland and Russia''. Three competence teams from each participant country studied, analyzed and examined these concepts from different point of view and introduced a framework to define the fundamental concepts of sustainability. This crucial phase of project based on the objectives and activities of each team could be described as follow: Team 1'' Engineering and Building Technology standards'' and related expertise emphasized on the most architectural solutions and characteristics of sustainability in very wide spectrum. That is realized through adaptable methods of design, typology, standards, assessment systems, proper and available materials with the best physical features, the most efficient and advanced structures and technologies in order to have the most possible energy and resource saving beside the less life cycle cost of the residential building. Team 2 '' Method of planning permit and tendering Procedure'' and its expertise from another point of view worked on the legal and administrative aspects of sustainability and examining possibility and capacity of each involved country to realize sustainable construction. Team 3 ''Economical and Financial basis, Industry and quality'' and its related expertise explained and examined the adequate and necessary tools for

  19. Can blueshifted Agn spectra explain B L Lac objects

    International Nuclear Information System (INIS)

    Basu, D.

    2009-01-01

    B L Lac spectra are almost completely devoid of any emission line, and absorption features are often present based on which redshifts are estimated. Several models have been proposed to explain the spectra, including the unification scheme currently most popular among astronomers. However, there appear to be ambiguities, uncertainties and contradictory results in this model, and many questions remain unanswered. Also, it involves the process of artificially enhancing the continuum to be concentrated to a high level, by the relativistically beaming jet action, in order to submerge the emission lines, partly or completely, to make them appear weak or invisible. Additionally, the sample based on which B L Lac objects have been included in the unification scheme is rather small to be statistically viable. In this context, we present an alternative and much simpler interpretation of the observed spectra of B L Lac objects, both emission and absorption, as blueshifted lines in Agn. Original spectra of fifty six objects available in the current literature are re-analyzed. Nine of these show only a single weak emission line and no absorption feature, while thirty five exhibit no emission feature but several absorption lines, and another twelve show more than one emission line and, in some cases, several absorption lines. It is demonstrated that emission lines in most B L Lac objects are blueshifted out of the visible region, and, hence, not seen at all. Emission lines, when seen, and absorption lines, are blueshifted and are identified with search lines of longer wavelengths that are naturally weak. Blue shifts, in emission and absorption features, are determined for all objects. Various considerations lead to the conclusion that the blue shift interpretation of B L Lac spectra is superior to and more important than the redshift interpretation. A possible explanation of observed blue shifts is presented in the scenario of the ejection process, a well-recognized mechanism

  20. The Keck/OSIRIS Nearby AGN Survey (KONA). I. The Nuclear K-band Properties of Nearby AGN

    Science.gov (United States)

    Müller-Sánchez, F.; Hicks, E. K. S.; Malkan, M.; Davies, R.; Yu, P. C.; Shaver, S.; Davis, B.

    2018-05-01

    We introduce the Keck OSIRIS Nearby AGN survey (KONA), a new adaptive optics-assisted integral-field spectroscopic survey of Seyfert galaxies. KONA permits at ∼0.″1 resolution a detailed study of the nuclear kinematic structure of gas and stars in a representative sample of 40 local bona fide active galactic nucleus (AGN). KONA seeks to characterize the physical processes responsible for the coevolution of supermassive black holes and galaxies, principally inflows and outflows. With these IFU data of the nuclear regions of 40 Seyfert galaxies, the KONA survey will be able to study, for the first time, a number of key topics with meaningful statistics. In this paper we study the nuclear K-band properties of nearby AGN. We find that the K-band (2.1 μm) luminosities of the compact Seyfert 1 nuclei are correlated with the hard X-ray luminosities, implying a non-stellar origin for the majority of the continuum emission. The best-fit correlation is log L K = 0.9log L 2–10 keV + 4 over three orders of magnitude in both K-band and X-ray luminosities. We find no strong correlation between 2.1 μm luminosity and hard X-ray luminosity for the Seyfert 2 galaxies. The spatial extent and spectral slope of the Seyfert 2 galaxies indicate the presence of nuclear star formation and attenuating material (gas and dust), which in some cases is compact and in some galaxies extended. We detect coronal-line emission in 36 galaxies and for the first time in 5 galaxies. Finally, we find 4/20 galaxies that are usually classified as Seyfert 2 based on their optical spectra exhibit a broad component of Brγ emission, and one galaxy (NGC 7465) shows evidence of a double nucleus. Based on observations at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The observatory was made possible by the generous financial support of the W. M

  1. Prospects for AGN Science using the ART-XC on the SRG Mission

    Science.gov (United States)

    Swartz, Douglas A.; Elsner, Ronald F.; Gubarev, Mikhail V.; O'Dell, Stephen L.; Ramsey, Brian D.; Bonamente, Massimiliano

    2012-01-01

    The enhanced hard X-ray sensitivity provided by the Astronomical Roentgen Telescope to the Spectrum Roentgen Gamma mission facilitates the detection of heavily obscured and other hard-spectrum cosmic X-ray sources. The SRG all-sky survey will obtain large, statistically-well-defined samples of active galactic nuclei (AGN) including a significant population of local heavily-obscured AGN. In anticipation of the SRG all-sky survey, we investigate the prospects for refining the bright end of the AGN luminosity function and determination of the local black hole mass function and comparing the spatial distribution of AGN with large-scale structure defined by galaxy clusters and groups. Particular emphasis is placed on studies of the deep survey Ecliptic Pole regions.

  2. AGN feedback through UFO and galaxy-wide winds in the early Universe

    Science.gov (United States)

    Feruglio, C.; Piconcelli, E.; Bischetti, M.; Zappacosta, L.; Fiore, F.

    2017-10-01

    AGN feedback through massive molecular winds is today routinely observed in local AGN host galaxies, but not as such in the early universe. I will present the first evidence for a massive, AGN-driven molecular wind in the z 4 QSO APM08279, which also hosts the most well studied and persistent nuclear semi-raltivistic wind (UFO). This observation directly probes the expansion mechanism of a nuclear wind into the ISM on galaxy wide scales, that so far was constrained by a couple of other objects only (Feruglio et al. 2015, Tombesi et al. 2015). This result also opens the path toward the exploration of molecular AGN-driven winds at early epochs, close after the end of the Epoch of Reionisation (EoR).

  3. AGN Obscuration Through Dusty Infrared Dominated Flows. 1; Radiation-Hydrodynamics Solution for the Wind

    Science.gov (United States)

    Dorodnitsyn, A.; Bisnovatyi-Kogan. G. S.; Kallman, T.

    2011-01-01

    We construct a radiation-hydrodynamics model for the obscuring toroidal structure in active galactic nuclei. In this model the obscuration is produced at parsec scale by a dense, dusty wind which is supported by infrared radiation pressure on dust grains. To find the distribution of radiation pressure, we numerically solve the 2D radiation transfer problem in a flux limited diffusion approximation. We iteratively couple the solution with calculations of stationary 1D models for the wind, and obtain the z-component of the velocity. Our results demonstrate that for AGN luminosities greater than 0.1 L(sub edd) external illumination can support a geometrically thick obscuration via outflows driven by infrared radiation pressure. The terminal velocity of marginally Compton-thin models (0.2 infrared-driven winds is a viable option for the AGN torus problem and AGN unification models. Such winds can also provide an important channel for AGN feedback.

  4. The 60 Month All-Sky Burst Alert Telescope Survey of Active Galactic Nucleus and the Anisotropy of Nearby AGNs

    Science.gov (United States)

    Ajello, M.; Alexander, D. M.; Greiner, J.; Madejeski, G. M.; Gehrels, N.; Burlon, D.

    2014-01-01

    Surveys above 10 keV represent one of the best resources to provide an unbiased census of the population of active galactic nuclei (AGNs). We present the results of 60 months of observation of the hard X-ray sky with Swift/Burst Alert Telescope (BAT). In this time frame, BAT-detected (in the 15-55 keV band) 720 sources in an all-sky survey of which 428 are associated with AGNs, most of which are nearby. Our sample has negligible incompleteness and statistics a factor of approx. 2 larger over similarly complete sets of AGNs. Our sample contains (at least) 15 bona fide Compton-thick AGNs and 3 likely candidates. Compton-thick AGNs represent approx. 5% of AGN samples detected above 15 keV. We use the BAT data set to refine the determination of the log N-log S of AGNs which is extremely important, now that NuSTAR prepares for launch, toward assessing the AGN contribution to the cosmic X-ray background. We show that the log N-log S of AGNs selected above 10 keV is now established to approx. 10% precision. We derive the luminosity function of Compton-thick AGNs and measure a space density of 7.9(+4.1/-2.9)× 10(exp -5)/cubic Mpc for objects with a de-absorbed luminosity larger than 2 × 10(exp 42) erg / s. As the BAT AGNs are all mostly local, they allow us to investigate the spatial distribution of AGNs in the nearby universe regardless of absorption. We find concentrations of AGNs that coincide spatially with the largest congregations of matter in the local (much < 85 Mpc) universe. There is some evidence that the fraction of Seyfert 2 objects is larger than average in the direction of these dense regions..

  5. Optical Time-Domain and Radio Imaging Analyses of the Dynamic Hearts of AGN

    Science.gov (United States)

    Smith, Krista Lynne

    Active galactic nuclei (AGN) are among the most extreme objects in the universe: galaxies with a central supermassive black hole feeding on gas from a hot accretion disk. Despite their potential as powerful tools to study topics ranging from relativity to cosmology, they remain quite mysterious. In the first portion of this thesis, we explore how an AGN may influence the formation of stars in its host galaxy. Using high-resolution 22 GHz radio imaging of an X-ray selected sample of radio-quiet AGN, we find that the far-infrared radio correlation for normal star forming galaxies remains valid within a few hundred parsecs of the central engine. Because the core flux is often spatially isolated from star formation, we can also determine that the radio emission in radio-quiet AGN is consistent with both coronal and disk-jet coupling models. Finally, we find that AGN with jet-like radio morphologies have suppressed star formation, possibly indicating ongoing feedback. The second portion of this thesis uses optical AGN light curves to study the physics of accretion. The Kepler spacecraft produces groundbreaking light curves, but its fixed field of view only contained a handful of known AGN. We conduct an X-ray survey of this field, yielding 93 unique X-ray sources identified by optical follow-up spectroscopy as a mixture of AGN and stars. For the AGN, we spectroscopically measure black hole masses and accretion rates. We then analyze a sample of 22 Kepler AGN light curves. We develop a customized pipeline for AGN science with Kepler, a necessary step since the initial data was optimized for the unique goal of exoplanet detection. The light curves display an astonishing variety of behaviors in a new regime of optical variability inaccessible with previous facilities. We find power spectral slopes inconsistent with the damped random walk model, characteristic variability timescales, correlations of variability properties with physical parameters, and bimodal flux

  6. Towards a Unified Programming Language

    DEFF Research Database (Denmark)

    Madsen, Ole Lehrmann

    2000-01-01

    The goal of research in programming languages should be to develop languages that integrates the best of concepts and constructs from the various programming paradigms. We do not argue for a multi-paradigm language, where the programmer alternates between the different paradigms/styles. Instead, we...... find that the languages of the future should integrate the best available concepts and constructs in such a way that the programmer does not think of multiple paradigms when using a given language. In this paper, we describe to what extent the BETA language has been successful in obtaining a unified...... style and where more research is needed. In addition to traditional paradigms such as object-oriented-, imperative-functional- and logic programming, we also discuss concurrent programming and prototype-based programming. We discuss language features such as the BETA pattern construct, virtual...

  7. A unified plant information network

    International Nuclear Information System (INIS)

    Niederauer, G.F.

    1986-01-01

    Technology is bringing power plants fully into the age of computerization. Microcomputers, data base managers, networking, and friendly, expert software are principal technology factors. Monitoring will improve, and the number and power of computers is increasing. The huge information flow will cause computers to be integrated into a communication network. The total plant operating triangle includes process, engineering, and management systems. The total network will integrate all of these into a Total Unified Plant Information Network (TUPIN). Software will take the type of information beyond monitored data. Analysis will improve through direct access to logical, physical, and procedural models by end users. Information management will improve through widespread use of hierarchical, relational, and expert data base managers. Expert systems will aid in diagnostics and interpretation. The goal is to automate plant operations to enhance safety and performance and to reduce cost by making both the plants and the personnel more expert

  8. Cosmology and unified gauge theory

    Science.gov (United States)

    Oraifeartaigh, L.

    1981-09-01

    Theoretical points in common between cosmology and unified gauge theory (UGT) are reviewed, with attention given to areas of one which have proven useful for the other. The underlying principles for both theoretical frameworks are described, noting the differences in scale, i.e., 10 to the 25th cm in cosmology and 10 to the -15th cm for UGT. Cosmology has produced bounds on the number of existing neutrino species, and also on the mass of neutrinos, two factors of interest in particle physics. Electrons, protons, and neutrinos, having been spawned from the same massive leptons, each composed of three quarks, have been predicted to be present in equal numbers in the Universe by UGT, in line with necessities of cosmology. The Grand UGT also suggests specific time scales for proton decay, thus accounting for the observed baryon assymmetry.

  9. Unifying physical concepts of reality

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, T.L.

    1983-08-01

    Physics may be characterized as the science of matter and energy. It anchors the two ends of the frontiers of science: the frontier of the very small and the frontier of the very large. All of the phenomena that we observe and study at the frontiers of science - all external experiences - are manifestations of matter and energy. One may, therefore, use physics to exemplify both the diversity and unity of science. This theme will be developed in two separate examples: first by sketching, very briefly, the historical origins of frontiers of the very small and very large and the converging unity of these two frontiers; and then by describing certain unifying concepts that play a central role in physics and provide a framework for relating developments in different sciences.

  10. Unifying physical concepts of reality

    International Nuclear Information System (INIS)

    Gilbert, T.L.

    1983-01-01

    Physics may be characterized as the science of matter and energy. It anchors the two ends of the frontiers of science: the frontier of the very small and the frontier of the very large. All of the phenomena that we observe and study at the frontiers of science - all external experiences - are manifestations of matter and energy. One may, therefore, use physics to exemplify both the diversity and unity of science. This theme will be developed in two separate examples: first by sketching, very briefly, the historical origins of frontiers of the very small and very large and the converging unity of these two frontiers; and then by describing certain unifying concepts that play a central role in physics and provide a framework for relating developments in different sciences

  11. Imprints of the large-scale structure on AGN formation and evolution

    Science.gov (United States)

    Porqueres, Natàlia; Jasche, Jens; Enßlin, Torsten A.; Lavaux, Guilhem

    2018-04-01

    Black hole masses are found to correlate with several global properties of their host galaxies, suggesting that black holes and galaxies have an intertwined evolution and that active galactic nuclei (AGN) have a significant impact on galaxy evolution. Since the large-scale environment can also affect AGN, this work studies how their formation and properties depend on the environment. We have used a reconstructed three-dimensional high-resolution density field obtained from a Bayesian large-scale structure reconstruction method applied to the 2M++ galaxy sample. A web-type classification relying on the shear tensor is used to identify different structures on the cosmic web, defining voids, sheets, filaments, and clusters. We confirm that the environmental density affects the AGN formation and their properties. We found that the AGN abundance is equivalent to the galaxy abundance, indicating that active and inactive galaxies reside in similar dark matter halos. However, occurrence rates are different for each spectral type and accretion rate. These differences are consistent with the AGN evolutionary sequence suggested by previous authors, Seyferts and Transition objects transforming into low-ionization nuclear emission line regions (LINERs), the weaker counterpart of Seyferts. We conclude that AGN properties depend on the environmental density more than on the web-type. More powerful starbursts and younger stellar populations are found in high densities, where interactions and mergers are more likely. AGN hosts show smaller masses in clusters for Seyferts and Transition objects, which might be due to gas stripping. In voids, the AGN population is dominated by the most massive galaxy hosts.

  12. Flickering AGN can explain the strong circumgalactic O VI observed by COS-Halos

    Science.gov (United States)

    Oppenheimer, Benjamin D.; Segers, Marijke; Schaye, Joop; Richings, Alexander J.; Crain, Robert A.

    2018-03-01

    Proximity zone fossils (PZFs) are ionization signatures around recently active galactic nuclei (AGNs) where metal species in the circumgalactic medium remain overionized after the AGNs have shut off due to their long recombination time scales. We explore cosmological zoom hydrodynamic simulations, using the EAGLE (Evolution and Assembly of GaLaxies and their Environments) model paired with a non-equilibrium ionization and cooling module including time-variable AGN radiation to model PZFs around star-forming disc galaxies in the z ˜ 0.2 Universe. Previous simulations typically underestimated the O VI content of galactic haloes, but we show that plausible PZF models increase O VI column densities by 2 - 3 × to achieve the levels observed around COS-Halos star-forming galaxies out to 150 kpc. Models with AGN bolometric luminosities ≳ 1043.6erg s- 1, duty cycle fractions ≲ 10 per cent, and AGN lifetimes ≲ 106 yr are the most promising, because their supermassive black holes grow at the cosmologically expected rate and they mostly appear as inactive AGN, consistent with COS-Halos. The central requirement is that the typical star-forming galaxy hosted an active AGN within a time-scale comparable to the recombination time of a high metal ion, which for circumgalactic O VI is ≈107 yr. H I, by contrast, returns to equilibrium much more rapidly due to its low neutral fraction and does not show a significant PZF effect. O VI absorption features originating from PZFs appear narrow, indicating photoionization, and are often well aligned with lower metal ion species. PZFs are highly likely to affect the physical interpretation of circumgalactic high ionization metal lines if, as expected, normal galaxies host flickering AGN.

  13. Uncovering extreme AGN variability in serendipitous X-ray source surveys

    Science.gov (United States)

    Moran, Edward C.; Garcia Soto, Aylin; LaMassa, Stephanie; Urry, Meg

    2018-01-01

    Constraints on the duty cycle and duration of accretion episodes in active galactic nuclei (AGNs) are vital for establishing how most AGNs are fueled, which is essential for a complete picture of black hole/galaxy co-evolution. Perhaps the best handle we have on these activity parameters is provided by AGNs that have displayed dramatic changes in their bolometric luminosities and, in some cases, spectroscopic classifications. Given that X-ray emission is directly linked to black-hole accretion, X-ray surveys should provide a straightforward means of identifying AGNs that have undergone dramatic changes in their accretion states. However, it appears that such events are very rare, so wide-area surveys separated in time by many years are needed to maximize discovery rates. We have cross-correlated the Einstein IPC Two-Sigma Catalog with the ROSAT All-Sky Survey Faint Source Catalog to identify a sample of soft X-ray sources that varied by factors ranging from 7 to more than 100 over a ten year timescale. When possible, we have constructed long-term X-ray light curves for the sources by combining the Einstein and RASS fluxes with those obtained from serendipitous pointed observations by ROSAT, Chandra,XMM, and Swift. Optical follow-up observations indicate that many of the extremely variable sources in our sample are indeed radio-quiet AGNs. Interestingly, the majority of objects that dimmed between ~1980 and ~1990 are still (or are again) broad-line AGNs rather than“changing-look” candidates that have more subtle AGN signatures in their spectra — despite the fact that none of the sources examined thus far has returned to its highest observed luminosity. Future X-ray observations will provide the opportunity to characterize the X-ray behavior of these anonymous, extreme AGNs over a four decade span.

  14. Unified gauge theories with spontaneous symmetry breaking

    International Nuclear Information System (INIS)

    MacDowell, S.W.

    1975-01-01

    Unified gauge theories with spontaneous symmetry breaking are studied with a view to renormalize quantum field theory. Georgi-Glashow and Weinberg-Salam models to unify weak and electromagnetic interactions are discussed in detail. Gauge theories of strong interactions are also considered [pt

  15. A unifying philosophy of governance

    Directory of Open Access Journals (Sweden)

    Sankarshan Acharya

    2012-09-01

    Full Text Available Bertrand Russell won Nobel Prize for arguing that science has triumphed over religion. Since religions are based on god, Russell’s argument implies that science has triumphed over both religion and god. But neither Russell nor anyone else has ever defined religion and god, rationally. The assertion about triumph of science (which is founded on rationality over concepts such as religion and god (which are not defined rationally or scientifically in the extant literature cannot be rational. This paper offers a novel rational philosophical foundation for the concepts of god, religion and science in which the claim that science triumphs over religion is redundant. This paper also presents substantial new insights about epistemic truths to help resolve current problems facing humanity like financial moral hazard and terrorism which have unnerved nations worldwide. The humanity now begs to answer a fundamental question of how we can govern ourselves. This paper offers a coherent set of credible answers. In particular, it offers a coherent unified philosophy about how humans have universally formed beliefs to govern themselves and how this philosophy could help resolve current problems. The universal rendering of beliefs articulated here subsumes the extant characterization of probability beliefs in mathematics, science, engineering, economics, religion and philosophy. The universal beliefs so articulated in this paper obviate the currently prevalent philosophical conflicts between religion and science or between theism and atheism and paves the way for optimal governance for prosperity amid stability. This philosophy also offers a rational characterization of the spiritual notion of Nirvana or salvation of the soul and the notion of epistemic truth. The unifying philosophy can help humanity achieve unity, stability and prosperity, sans financial moral hazard, antagonism, wars, nuclear proliferation, global warming and atmospheric pollution.

  16. Remnant radio-loud AGN in the Herschel-ATLAS field

    Science.gov (United States)

    Mahatma, V. H.; Hardcastle, M. J.; Williams, W. L.; Brienza, M.; Brüggen, M.; Croston, J. H.; Gurkan, G.; Harwood, J. J.; Kunert-Bajraszewska, M.; Morganti, R.; Röttgering, H. J. A.; Shimwell, T. W.; Tasse, C.

    2018-04-01

    Only a small fraction of observed active galactic nuclei (AGN) display large-scale radio emission associated with jets, yet these radio-loud AGN have become increasingly important in models of galaxy evolution. In determining the dynamics and energetics of the radio sources over cosmic time, a key question concerns what happens when their jets switch off. The resulting `remnant' radio-loud AGN have been surprisingly evasive in past radio surveys, and therefore statistical information on the population of radio-loud AGN in their dying phase is limited. In this paper, with the recent developments of Low-Frequency Array (LOFAR) and the Very Large Array, we are able to provide a systematically selected sample of remnant radio-loud AGN in the Herschel-ATLAS field. Using a simple core-detection method, we constrain the upper limit on the fraction of remnants in our radio-loud AGN sample to 9 per cent, implying that the extended lobe emission fades rapidly once the core/jets turn off. We also find that our remnant sample has a wide range of spectral indices (-1.5≤slant α ^{1400}_{150}≤slant -0.5), confirming that the lobes of some remnants may possess flat spectra at low frequencies just as active sources do. We suggest that, even with the unprecedented sensitivity of LOFAR, our sample may still only contain the youngest of the remnant population.

  17. Multi-Frequency Databases for AGN Investigation—Results and Perspectives

    Energy Technology Data Exchange (ETDEWEB)

    La Mura, Giovanni [Department of Physics and Astronomy, University of Padua, Padua (Italy); Berton, Marco [Department of Physics and Astronomy, University of Padua, Padua (Italy); Astronomical Observatory of Brera, National Institute for Astrophysics, Milan (Italy); Chen, Sina; Ciroi, Stefano [Department of Physics and Astronomy, University of Padua, Padua (Italy); Congiu, Enrico [Department of Physics and Astronomy, University of Padua, Padua (Italy); Astronomical Observatory of Brera, National Institute for Astrophysics, Milan (Italy); Cracco, Valentina; Frezzato, Michele; Rafanelli, Piero, E-mail: giovanni.lamura@unipd.it [Department of Physics and Astronomy, University of Padua, Padua (Italy)

    2017-10-17

    Active Galactic Nuclei (AGNs) are characterized by emission of radiation over more than 10 orders of magnitude in frequency. Therefore, the execution of extensive surveys of the sky, with different types of detectors, is providing the attractive possibility to identify and to investigate the properties of AGNs on very large statistical samples. Thanks to the large spectroscopic surveys that allow detailed investigation of many of these sources, we have the opportunity to place new constraints on the nature and evolution of AGNs and to investigate their relations with the host systems. In this contribution we present the results that can be obtained by using a new interactive catalog that we developed to investigate the range of AGN spectral energy distributions (SEDs). We present simple SED models based on data collected in the catalog and discuss their relations with optical spectra obtained by follow up observations. We compare our findings with the expectations based on the AGN Unification Model, and we discuss the perspectives of multi-wavelength approaches to address AGN related processes such as black hole accretion and acceleration of relativistic jets.

  18. A statistical study of H i gas in nearby narrow-line AGN-hosting galaxies

    International Nuclear Information System (INIS)

    Zhu, Yi-Nan; Wu, Hong

    2015-01-01

    As a quenching mechanism, active galactic nucleus (AGN) feedback could suppress on going star formation in host galaxies. On the basis of a sample of galaxies selected from the Arecibo Legacy Fast ALFA (ALFALFA) H i survey, the dependence of the H i mass (M H i ), stellar mass (M * ), and H i-to-stellar mass ratio (M H i /M * ) on various tracers of AGN activity are presented and analyzed in this paper. Almost all the AGN hostings in this sample are gas-rich galaxies, and there is not any evidence to indicate that the AGN activity could increase or decrease either M H i or M H i /M * . The position of the cold neutral gas cannot be fixed accurately based only on available H i data, due to the large beam size of ALFALFA survey. In addition, even though AGN hostings are more easily detected by an H i survey compared with absorption line galaxies, these two types of galaxies show similar star formation history. If an AGN hosting would ultimately evolve into an old red galaxy with low cold gas, then when and how the gas has been exhausted must be solved by future hypotheses and observations.

  19. A statistical study of H i gas in nearby narrow-line AGN-hosting galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yi-Nan; Wu, Hong, E-mail: zyn@bao.ac.cn, E-mail: hwu@bao.ac.cn [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2015-01-01

    As a quenching mechanism, active galactic nucleus (AGN) feedback could suppress on going star formation in host galaxies. On the basis of a sample of galaxies selected from the Arecibo Legacy Fast ALFA (ALFALFA) H i survey, the dependence of the H i mass (M{sub H} {sub i}), stellar mass (M{sub *}), and H i-to-stellar mass ratio (M{sub H} {sub i}/M{sub *}) on various tracers of AGN activity are presented and analyzed in this paper. Almost all the AGN hostings in this sample are gas-rich galaxies, and there is not any evidence to indicate that the AGN activity could increase or decrease either M{sub H} {sub i} or M{sub H} {sub i}/M{sub *}. The position of the cold neutral gas cannot be fixed accurately based only on available H i data, due to the large beam size of ALFALFA survey. In addition, even though AGN hostings are more easily detected by an H i survey compared with absorption line galaxies, these two types of galaxies show similar star formation history. If an AGN hosting would ultimately evolve into an old red galaxy with low cold gas, then when and how the gas has been exhausted must be solved by future hypotheses and observations.

  20. Research and Design in Unified Coding Architecture for Smart Grids

    Directory of Open Access Journals (Sweden)

    Gang Han

    2013-09-01

    Full Text Available Standardized and sharing information platform is the foundation of the Smart Grids. In order to improve the dispatching center information integration of the power grids and achieve efficient data exchange, sharing and interoperability, a unified coding architecture is proposed. The architecture includes coding management layer, coding generation layer, information models layer and application system layer. Hierarchical design makes the whole coding architecture to adapt to different application environments, different interfaces, loosely coupled requirements, which can realize the integration model management function of the power grids. The life cycle and evaluation method of survival of unified coding architecture is proposed. It can ensure the stability and availability of the coding architecture. Finally, the development direction of coding technology of the Smart Grids in future is prospected.

  1. Reduction of parameters in Finite Unified Theories and the MSSM

    Science.gov (United States)

    Heinemeyer, Sven; Mondragón, Myriam; Tracas, Nicholas; Zoupanos, George

    2018-02-01

    The method of reduction of couplings developed by W. Zimmermann, combined with supersymmetry, can lead to realistic quantum field theories, where the gauge and Yukawa sectors are related. It is the basis to find all-loop Finite Unified Theories, where the β-function vanishes to all-loops in perturbation theory. It can also be applied to the Minimal Supersymmetric Standard Model, leading to a drastic reduction in the number of parameters. Both Finite Unified Theories and the reduced MSSM lead to successful predictions for the masses of the third generation of quarks and the Higgs boson, and also predict a heavy supersymmetric spectrum, consistent with the non-observation of supersymmetry so far.

  2. Seagrass from Unified Florida Reef Tract Map (NODC Accession 0123059)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a subset of the Unified Map representing Seagrass areas. Version 1.1 - December 2013. The Unified Florida Reef Tract Map (Unified Reef Map) provides...

  3. Cutting the Composite Gordian Knot: Untangling the AGN-Starburst Threads in Single Aperture Spectra

    Science.gov (United States)

    Flury, Sophia; Moran, Edward C.

    2018-01-01

    Standard emission line diagnostics are able to segregate star-forming galaxies and Seyfert nuclei, and it is often assumed that ambiguous emission-line galaxies falling between these two populations are “composite” objects exhibiting both types of photoionization. We have developed a method that predicts the most probable H II and AGN components that could plausibly explain the “composite” classed objects solely on the basis of their SDSS spectra. The majority of our analysis is driven by empirical relationships revealed by SDSS data rather than theoretical models founded in assumptions. To verify our method, we have compared the predictions of our model with publicly released IFU data from the S7 survey and find that composite objects are not in fact a simple linear combination of the two types of emission. The data reveal a key component in the mixing sequence: geometric dilution of the ionizing radiation which powers the NLR of the active nucleus. When accounting for this effect, our model is successful when applied to several composite-class galaxies. Some objects, however, appear to be at variance with the predicted results, suggesting they may not be powered by black hole accretion.

  4. EDDINGTON RATIO DISTRIBUTION OF X-RAY-SELECTED BROAD-LINE AGNs AT 1.0 < z < 2.2

    International Nuclear Information System (INIS)

    Suh, Hyewon; Hasinger, Günther; Steinhardt, Charles; Silverman, John D.; Schramm, Malte

    2015-01-01

    We investigate the Eddington ratio distribution of X-ray-selected broad-line active galactic nuclei (AGNs) in the redshift range 1.0 < z < 2.2, where the number density of AGNs peaks. Combining the optical and Subaru/Fiber Multi Object Spectrograph near-infrared spectroscopy, we estimate black hole masses for broad-line AGNs in the Chandra Deep Field South (CDF-S), Extended Chandra Deep Field South (E-CDF-S), and the XMM-Newton Lockman Hole (XMM-LH) surveys. AGNs with similar black hole masses show a broad range of AGN bolometric luminosities, which are calculated from X-ray luminosities, indicating that the accretion rate of black holes is widely distributed. We find a substantial fraction of massive black holes accreting significantly below the Eddington limit at z ≲ 2, in contrast to what is generally found for luminous AGNs at high redshift. Our analysis of observational selection biases indicates that the “AGN cosmic downsizing” phenomenon can be simply explained by the strong evolution of the comoving number density at the bright end of the AGN luminosity function, together with the corresponding selection effects. However, one might need to consider a correlation between the AGN luminosity and the accretion rate of black holes, in which luminous AGNs have higher Eddington ratios than low-luminosity AGNs, in order to understand the relatively small fraction of low-luminosity AGNs with high accretion rates in this epoch. Therefore, the observed downsizing trend could be interpreted as massive black holes with low accretion rates, which are relatively fainter than less-massive black holes with efficient accretion

  5. PRIMUS: THE DEPENDENCE OF AGN ACCRETION ON HOST STELLAR MASS AND COLOR

    Energy Technology Data Exchange (ETDEWEB)

    Aird, James; Coil, Alison L.; Moustakas, John; Smith, M. Stephen M. [Center for Astrophysics and Space Sciences, Department of Physics, University of California, 9500 Gilman Dr., La Jolla, San Diego, CA 92093 (United States); Blanton, Michael R.; Zhu Guangtun [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Burles, Scott M. [D.E. Shaw and Co., L.P., 20400 Stevens Creek Blvd., Suite 850, Cupertino, CA 95014 (United States); Cool, Richard J. [Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544 (United States); Eisenstein, Daniel J. [Harvard College Observatory, 60 Garden St., Cambridge, MA 02138 (United States); Wong, Kenneth C. [Steward Observatory, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 (United States)

    2012-02-10

    We present evidence that the incidence of active galactic nuclei (AGNs) and the distribution of their accretion rates do not depend on the stellar masses of their host galaxies, contrary to previous studies. We use hard (2-10 keV) X-ray data from three extragalactic fields (XMM-LSS, COSMOS, and ELAIS-S1) with redshifts from the Prism Multi-object Survey to identify 242 AGNs with L{sub 2-10keV} = 10{sup 42-44} erg s{sup -1} within a parent sample of {approx}25,000 galaxies at 0.2 < z < 1.0 over {approx}3.4 deg{sup 2} and to i {approx} 23. We find that although the fraction of galaxies hosting an AGN at fixed X-ray luminosity rises strongly with stellar mass, the distribution of X-ray luminosities is independent of mass. Furthermore, we show that the probability that a galaxy will host an AGN can be defined by a universal Eddington ratio distribution that is independent of the host galaxy stellar mass and has a power-law shape with slope -0.65. These results demonstrate that AGNs are prevalent at all stellar masses in the range 9.5< log M{sub *}/M{sub sun}<12 and that the same physical processes regulate AGN activity in all galaxies in this stellar mass range. While a higher AGN fraction may be observed in massive galaxies, this is a selection effect related to the underlying Eddington ratio distribution. We also find that the AGN fraction drops rapidly between z {approx} 1 and the present day and is moderately enhanced (factor {approx}2) in galaxies with blue or green optical colors. Consequently, while AGN activity and star formation appear to be globally correlated, we do not find evidence that the presence of an AGN is related to the quenching of star formation or the color transformation of galaxies.

  6. The Contribution of Compton-Thick AGN/ULIRGs to the X-Ray Background

    Science.gov (United States)

    Nardini, Emanuele

    Accretion onto the supermassive black holes located at the centre of Active Galactic Nuclei(AGN) is one of the most efficient power sources in the Universe, and provides a significant contribution to the energy radiated over cosmic times. The spectral shape of the X-ray background and its progressive resolution strongly suggests that most AGN are heavily obscured by large amounts of dust and gas. Their primary radiation field is reprocessed and re-emitted at longer wavelengths, driving a huge IR luminosity. Ultraluminous Infrared Galaxies (ULIRGs) are the local counterparts of the high-redshift (z sport the typical features of buried AGN in the mid-IR. IRAS 12127 1412 was observed for the first time in the X-rays by our group. Its Chandra spectrum clearly shows the signatures of AGN reflection at 2 10 keV. Similar properties were previously found in IRAS 00182 7112. Our Suzaku observations will allow to pinpont the AGN emission above 10 keV, and will provide fundamental information on the physical and geometrical structure of Compton-thick AGN embedded in a nuclear starburst. These sources are believed to experience the very initial phase of the AGN feedback on the surrounding environment, eventually leading to the formation of powerful optically- bright quasars. Besides this, we stress another remarkable opportunity related to the study of these two ULIRGs. Due to their really unique mid-IR and hard X-ray spectral properties, IRAS 00182 7112 and IRAS 12127 1412 can be considered as representative templates for a significant fraction of the obscured AGN population. Their broadband spectral energy distribution can then be used to calibrate new photometric diagnostics based on mid-IR colors and bolometric corrections, capable of selecting their faint counterparts within the IR deep fields. The wealth of data in the WISE and Spitzer archives will allow a complete census of this AGN subclass. The reflection efficiency inferred from our new Suzaku observations will make

  7. THE HOST GALAXY PROPERTIES OF VARIABILITY SELECTED AGN IN THE PAN-STARRS1 MEDIUM DEEP SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Heinis, S.; Gezari, S.; Kumar, S. [Department of Astronomy, University of Maryland, College Park, MD (United States); Burgett, W. S.; Flewelling, H.; Huber, M. E.; Kaiser, N.; Wainscoat, R. J.; Waters, C. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

    2016-07-20

    We study the properties of 975 active galactic nuclei (AGNs) selected by variability in the Pan-STARRS1 Medium deep Survey. Using complementary multi-wavelength data from the ultraviolet to the far-infrared, we use spectral energy distribution fitting to determine the AGN and host properties at z < 1 and compare to a well-matched control sample. We confirm the trend previously observed: that the variability amplitude decreases with AGN luminosity, but we also observe that the slope of this relation steepens with wavelength, resulting in a “redder when brighter” trend at low luminosities. Our results show that AGNs are hosted by more massive hosts than control sample galaxies, while the rest frame dust-corrected NUV r color distribution of AGN hosts is similar to control galaxies. We find a positive correlation between the AGN luminosity and star formation rate (SFR), independent of redshift. AGN hosts populate the entire range of SFRs within and outside of the Main Sequence of star-forming galaxies. Comparing the distribution of AGN hosts and control galaxies, we show that AGN hosts are less likely to be hosted by quiescent galaxies and more likely to be hosted by Main Sequence or starburst galaxies.

  8. A fragilidade das Instituições Sociais e o rompimento da Ética no filme Agnes de Deus.

    OpenAIRE

    Marco Antonio Palermo Moretto

    2015-01-01

    Research about the fragilities of the social institutions in the movie Agnes of God and the ethic and moral. There are a mistery in the story:a murder of the baby inside the convent.  The young nun, Agnes killed her baby and a psichiatrist. Dra. Martha Livingstone  begans a investigation since the childhood of Agnes until the crime. The presence of the Superior Mother, Mirian Ruth is important to the story. She is an administrator and protect Agnes in many situations. Such social institutions...

  9. A Product Line Enhanced Unified Process

    DEFF Research Database (Denmark)

    Zhang, Weishan; Kunz, Thomas

    2006-01-01

    The Unified Process facilitates reuse for a single system, but falls short handling multiple similar products. In this paper we present an enhanced Unified Process, called UPEPL, integrating the product line technology in order to alleviate this problem. In UPEPL, the product line related activit...... activities are added and could be conducted side by side with other classical UP activities. In this way both the advantages of Unified Process and software product lines could co-exist in UPEPL. We show how to use UPEPL with an industrial mobile device product line in our case study....

  10. A Unified Grand Tour of Theoretical Physics

    CERN Document Server

    Lawrie, Ian D

    2002-01-01

    A unified account of the principles of theoretical physics, A Unified Grand Tour of Theoretical Physics, Second Edition stresses the inter-relationships between areas that are usually treated as independent. The profound unifying influence of geometrical ideas, the powerful formal similarities between statistical mechanics and quantum field theory, and the ubiquitous role of symmetries in determining the essential structure of physical theories are emphasized throughout.This second edition conducts a grand tour of the fundamental theories that shape our modern understanding of the physical wor

  11. The unified theory of nuclear reactions

    International Nuclear Information System (INIS)

    Tobocman, W.

    A unified nuclear reaction theory is a formalism for the scattering reactions of many-body nuclear systems which is capable of describing both direct interaction and compound nucleus formation processes. The Feshbach projection operator formalism is the original unified nuclear reaction theory. An alternative unified nuclear reaction theory called the X-matrix formalism is described. The X-matrix formalism is a generalization of the Brown-de Dominicis formalism. It does not require projection operators and is readly applied to rearrangement collisions

  12. AGNES at vibrated gold microwire electrode for the direct quantification of free copper concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Domingos, Rute F., E-mail: rdomingos@ipgp.fr [Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Torre Sul Lab 11-6.3, Av. Rovisco Pais #1, 1049-001 Lisbon (Portugal); Carreira, Sara [Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Torre Sul Lab 11-6.3, Av. Rovisco Pais #1, 1049-001 Lisbon (Portugal); Galceran, Josep [Department of Chemistry, University of Lleida and Agrotecnio, Rovira Roure 191, 25198 Lleida (Spain); Salaün, Pascal [School of Environmental Sciences, University of Liverpool, 4 Brownlow Street, Liverpool L693 GP (United Kingdom); Pinheiro, José P. [LIEC/ENSG, UMR 7360 CNRS – Université de Lorraine, 15 Avenue du Charmois, 54500 Vandoeuvre-les-Nancy (France)

    2016-05-12

    The free metal ion concentration and the dynamic features of the metal species are recognized as key to predict metal bioavailability and toxicity to aquatic organisms. Quantification of the former is, however, still challenging. In this paper, it is shown for the first time that the concentration of free copper (Cu{sup 2+}) can be quantified by applying AGNES (Absence of Gradients and Nernstian equilibrium stripping) at a solid gold electrode. It was found that: i) the amount of deposited Cu follows a Nernstian relationship with the applied deposition potential, and ii) the stripping signal is linearly related with the free metal ion concentration. The performance of AGNES at the vibrating gold microwire electrode (VGME) was assessed for two labile systems: Cu-malonic acid and Cu-iminodiacetic acid at ionic strength 0.01 M and a range of pH values from 4.0 to 6.0. The free Cu concentrations and conditional stability constants obtained by AGNES were in good agreement with stripping scanned voltammetry and thermodynamic theoretical predictions obtained by Visual MinteQ. This work highlights the suitability of gold electrodes for the quantification of free metal ion concentrations by AGNES. It also strongly suggests that other solid electrodes may be well appropriate for such task. This new application of AGNES is a first step towards a range of applications for a number of metals in speciation, toxicological and environmental studies for the direct determination of the key parameter that is the free metal ion concentration. - Highlights: • AGNES principles are valid at the vibrating gold microwire electrode (VGME). • VGME was successfully employed to quantify free Cu concentrations by using AGNES. • Stability constants of labile systems were in good agreement with predictions.

  13. Dust-deficient Palomar-Green Quasars and the Diversity of AGN Intrinsic IR Emission

    Energy Technology Data Exchange (ETDEWEB)

    Lyu, Jianwei; Rieke, G. H. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Shi, Yong, E-mail: jianwei@email.arizona.edu [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)

    2017-02-01

    To elucidate the intrinsic broadband infrared (IR) emission properties of active galactic nuclei (AGNs), we analyze the spectral energy distributions (SEDs) of 87 z ≲ 0.5 Palomar-Green (PG) quasars. While the Elvis AGN template with a moderate far-IR correction can reasonably match the SEDs of the AGN components in ∼60% of the sample (and is superior to alternatives such as that by Assef), it fails on two quasar populations: (1) hot-dust-deficient (HDD) quasars that show very weak emission thoroughly from the near-IR to the far-IR, and (2) warm-dust-deficient (WDD) quasars that have similar hot dust emission as normal quasars but are relatively faint in the mid- and far-IR. After building composite AGN templates for these dust-deficient quasars, we successfully fit the 0.3–500 μm SEDs of the PG sample with the appropriate AGN template, an infrared template of a star-forming galaxy, and a host galaxy stellar template. 20 HDD and 12 WDD quasars are identified from the SED decomposition, including seven ambiguous cases. Compared with normal quasars, the HDD quasars have AGNs with relatively low Eddington ratios and the fraction of WDD quasars increases with AGN luminosity. Moreover, both the HDD and WDD quasar populations show relatively stronger mid-IR silicate emission. Virtually identical SED properties are also found in some quasars from z = 0.5 to 6. We propose a conceptual model to demonstrate that the observed dust deficiency of quasars can result from a change of structures of the circumnuclear tori that can occur at any cosmic epoch.

  14. Nuclear mid-infrared properties of nearby low-luminosity AGN

    International Nuclear Information System (INIS)

    Asmus, D; Duschl, W J; Hönig, S F; Gandhi, P; Smette, A

    2012-01-01

    We present ground-based high-spatial resolution mid-infrared (MIR) observations of 20 nearby low-luminosity AGN (LLAGN) with VLT/VISIR and the preliminary analysis of a new sample of 10 low-luminosity Seyferts observed with Gemini/Michelle. LLAGN are of great interest because these objects are the most common among active galaxies, especially in the nearby universe. Studying them in great detail makes it possible to investigate the AGN evolution over cosmic timescale. Indeed, many LLAGN likely represent the final stage of an AGN's lifetime. We show that even at low luminosities and accretion rates nuclear unresolved MIR emission is present in most objects. Compared to lower spatial resolution Spitzer/IRS spectra, the high-resolution MIR photometry exhibits significantly lower fluxes and different PAH emission feature properties in many cases. By using scaled Spitzer/IRS spectra of typical starburst galaxies, we show that the star formation contribution to the 12 μm emission is minor in the central parsecs of most LLAGN. Therefore, the observed MIR emission in the VISIR and Michelle data is most likely emitted by the AGN itself, which, for higher luminosity AGN, is interpreted as thermal emission from a dusty torus. Furthermore, the 12 /amemission of the LLAGN is strongly correlated with the absorption corrected 2-10 keV luminosity and the MIR- X-ray correlation found previously for AGN is extended to a range from 10 40 to 10 45 erg/s. This correlation is independent of the object type, and in particular the low-luminosity Seyferts observed with Michelle fall exactly on the power-law fit valid for brighter AGN. In addition, no dependency of the MIR-X-ray ratio on the accretion rate is found. These results are consistent with the unification model being applicable even in the probed low-luminosity regime.

  15. The Role of the Most Luminous Obscured AGNs in Galaxy Assembly at z ∼ 2

    Energy Technology Data Exchange (ETDEWEB)

    Farrah, Duncan [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States); Petty, Sara [Green Science Policy Institute, Berkeley, CA 94709 (United States); Connolly, Brian [Cincinnati Children’s Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229 (United States); Blain, Andrew [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom); Efstathiou, Andreas [School of Sciences, European University Cyprus, Diogenes Street, Engomi, 1516 Nicosia (Cyprus); Lacy, Mark [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Stern, Daniel; Bridge, Carrie; Eisenhardt, Peter; Moustakas, Leonidas [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Lake, Sean; Tsai, Chao-Wei [Physics and Astronomy Department, University of California, Los Angeles, CA 90095 (United States); Jarrett, Tom [Department of Astronomy, University of Cape Town, 7700 Rondebosch, Capetown 7700 (South Africa); Benford, Dominic [Observational Cosmology Lab., Code 665, NASA at Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Jones, Suzy [Department of Space, Earth, and Environment, Chalmers University of Technology, Onsala Space Observatory, SE-43992 Onsala (Sweden); Assef, Roberto [Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago (Chile); Wu, Jingwen [National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing, 100012 (China)

    2017-08-01

    We present Hubble Space Telescope WFC3 F160W imaging and infrared spectral energy distributions for 12 extremely luminous, obscured active galactic nuclei (AGNs) at 1.8 < z < 2.7 selected via “hot, dust-obscured” mid-infrared colors. Their infrared luminosities span (2–15) × 10{sup 13} L {sub ⊙}, making them among the most luminous objects in the universe at z ∼ 2. In all cases, the infrared emission is consistent with arising at least for the most part from AGN activity. The AGN fractional luminosities are higher than those in either submillimeter galaxies or AGNs selected via other mid-infrared criteria. Adopting the G , M {sub 20}, and A morphological parameters, together with traditional classification boundaries, infers that three-quarters of the sample are mergers. Our sample does not, however, show any correlation between the considered morphological parameters and either infrared luminosity or AGN fractional luminosity. Moreover, the asymmetries and effective radii of our sample are distributed identically to those of massive galaxies at z ∼ 2. We conclude that our sample is not preferentially associated with mergers, though a significant merger fraction is still plausible. Instead, we propose that our sample includes examples of the massive galaxy population at z ∼ 2 that harbor a briefly luminous, “flickering” AGN and in which the G and M {sub 20} values have been perturbed due to either the AGN and/or the earliest formation stages of a bulge in an inside-out manner. Furthermore, we find that the mass assembly of the central black holes in our sample leads the mass assembly of any bulge component. Finally, we speculate that our sample represents a small fraction of the immediate antecedents of compact star-forming galaxies at z ∼ 2.

  16. A unifying conceptual model of entrepreneurial management

    DEFF Research Database (Denmark)

    Senderovitz, Martin

    This article offers a systematic analysis and synthesis of the area of entrepreneurial management. Through a presentation of two main perspectives on entrepreneurial management and a newly developed unifying conceptual entrepreneurial management model, the paper discusses a number of theoretical...

  17. Unified data model for biological data

    International Nuclear Information System (INIS)

    Idrees, M.

    2014-01-01

    A data model empowers us to store, retrieve and manipulate data in a unified way. We consider the biological data consists of DNA (De-Oxyribonucleic Acid), RNA (Ribonucleic Acid) and protein structures. In our Bioinformatics Lab (Bioinformatics Lab, Alkhawarizmi Institute of Computer Science, University of Engineering and Technology, Lahore, Pakistan), we have already proposed two data models for DNA and protein structures individually. In this paper, we propose a unified data model by using the data models of TOS (Temporal Object Oriented System) after making some necessary modifications to this data model and our already proposed the two data models. This proposed unified data model can be used for the modeling and maintaining the biological data (i.e. DNA, RNA and protein structures), in a single unified way. (author)

  18. 76 FR 19893 - Unified Command Plan 2011

    Science.gov (United States)

    2011-04-08

    ... Plan 2011 Memorandum for the Secretary of Defense Pursuant to my authority as Commander in Chief, I hereby approve and direct the implementation of the revised Unified Command Plan. Consistent with title...

  19. Development of unified gauge theories: retrospect

    International Nuclear Information System (INIS)

    Lee, B.W.

    1977-01-01

    The construction and development of unified gauge theory of weak, electromagnetic, and strong interactions is reviewed. The Weinberg and Lee contributions to this study are mainly considered as personal recollections

  20. Unified universal quantum cloning machine and fidelities

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yinan; Shi Handuo; Xiong Zhaoxi; Jing Li; Mu Liangzhu [School of Physics, Peking University, Beijing 100871 (China); Ren Xijun [School of Physics and Electronics, Henan University, Kaifeng 4750011 (China); Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2011-09-15

    We present a unified universal quantum cloning machine, which combines several different existing universal cloning machines together, including the asymmetric case. In this unified framework, the identical pure states are projected equally into each copy initially constituted by input and one half of the maximally entangled states. We show explicitly that the output states of those universal cloning machines are the same. One importance of this unified cloning machine is that the cloning procession is always the symmetric projection, which reduces dramatically the difficulties for implementation. Also, it is found that this unified cloning machine can be directly modified to the general asymmetric case. Besides the global fidelity and the single-copy fidelity, we also present all possible arbitrary-copy fidelities.

  1. Unified Approach in the DSS Development Process

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The structure of today's decision support environment become very complex due to new generation of Business Intelligence applications and technologies like Data Warehouse, OLAP (On Line Analytical Processing and Data Mining. In this respect DSS development process are not simple and needs an adequate methodology or framework able to manage different tools and platforms to achieve manager's requirements. The DSS development process must be view like a unified and iterative set of activities and operations. The new techniques based on Unified Process (UP methodology and UML (Unified Modeling Language it seems to be appropriate for DSS development using prototyping and RAD (Rapid Application Development techniques. In this paper we present a conceptual framework for development and integrate Decision Support Systems using Unified Process Methodology and UML.

  2. Unified Chiral models of mesons and baryons

    International Nuclear Information System (INIS)

    Mendez-Galain, R.; Ripka, G.

    1990-01-01

    Unified Chiral models of mesons and baryons are presented. Emphasis is placed on the underlying quark structure of hadrons including the Skyrmion. The Nambu Jona-Lasinio model with vector mesons is discussed

  3. CANDELS: CONSTRAINING THE AGN-MERGER CONNECTION WITH HOST MORPHOLOGIES AT z {approx} 2

    Energy Technology Data Exchange (ETDEWEB)

    Kocevski, Dale D.; Faber, S. M.; Mozena, Mark; Trump, Jonathan R.; Koo, David C. [University of California Observatories/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Koekemoer, Anton M.; Somerville, Rachel S.; Lotz, Jennifer M.; Dahlen, Tomas; Donley, Jennifer L. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Nandra, Kirpal; Brusa, Marcella; Wuyts, Stijn [Max-Planck-Institut fuer extraterrestrische Physik, D-85748 Garching (Germany); Rangel, Cyprian; Laird, Elise S. [Astrophysics Group, Imperial College London, London, SW7 2AZ (United Kingdom); Bell, Eric F. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Alexander, David M. [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Bournaud, Frederic [CEA, IRFU, SAp and Laboratoire AIM Paris-Saclay, F-91191 Gif-sur-Yvette (France); Conselice, Christopher J. [Centre for Astronomy and Particle Theory, University of Nottingham, Nottingham, NG7 2RD (United Kingdom); Dekel, Avishai, E-mail: kocevski@ucolick.org [Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel); and others

    2012-01-10

    Using Hubble Space Telescope/WFC3 imaging taken as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, we examine the role that major galaxy mergers play in triggering active galactic nucleus (AGN) activity at z {approx} 2. Our sample consists of 72 moderate-luminosity (L{sub X} {approx} 10{sup 42-44} erg s{sup -1}) AGNs at 1.5 < z < 2.5 that are selected using the 4 Ms Chandra observations in the Chandra Deep Field South, the deepest X-ray observations to date. Employing visual classifications, we have analyzed the rest-frame optical morphologies of the AGN host galaxies and compared them to a mass-matched control sample of 216 non-active galaxies at the same redshift. We find that most of the AGNs reside in disk galaxies (51.4{sup +5.8}{sub -5.9}%), while a smaller percentage are found in spheroids (27.8{sup +5.8}{sub -4.6}%). Roughly 16.7{sup +5.3}{sub -3.5}% of the AGN hosts have highly disturbed morphologies and appear to be involved in a major merger or interaction, while most of the hosts (55.6{sup +5.6}{sub -5.9}%) appear relatively relaxed and undisturbed. These fractions are statistically consistent with the fraction of control galaxies that show similar morphological disturbances. These results suggest that the hosts of moderate-luminosity AGNs are no more likely to be involved in an ongoing merger or interaction relative to non-active galaxies of similar mass at z {approx} 2. The high disk fraction observed among the AGN hosts also appears to be at odds with predictions that merger-driven accretion should be the dominant AGN fueling mode at z {approx} 2, even at moderate X-ray luminosities. Although we cannot rule out that minor mergers are responsible for triggering these systems, the presence of a large population of relatively undisturbed disk-like hosts suggests that the stochastic accretion of gas plays a greater role in fueling AGN activity at z {approx} 2 than previously thought.

  4. Self-consistent two-phase AGN torus models⋆. SED library for observers

    Science.gov (United States)

    Siebenmorgen, Ralf; Heymann, Frank; Efstathiou, Andreas

    2015-11-01

    We assume that dust near active galactic nuclei (AGNs) is distributed in a torus-like geometry, which can be described as a clumpy medium or a homogeneous disk, or as a combination of the two (i.e. a two-phase medium). The dust particles considered are fluffy and have higher submillimeter emissivities than grains in the diffuse interstellar medium. The dust-photon interaction is treated in a fully self-consistent three-dimensional radiative transfer code. We provide an AGN library of spectral energy distributions (SEDs). Its purpose is to quickly obtain estimates of the basic parameters of the AGNs, such as the intrinsic luminosity of the central source, the viewing angle, the inner radius, the volume filling factor and optical depth of the clouds, and the optical depth of the disk midplane, and to predict the flux at yet unobserved wavelengths. The procedure is simple and consists of finding an element in the library that matches the observations. We discuss the general properties of the models and in particular the 10 μm silicate band. The AGN library accounts well for the observed scatter of the feature strengths and wavelengths of the peak emission. AGN extinction curves are discussed and we find that there is no direct one-to-one link between the observed extinction and the wavelength dependence of the dust cross sections. We show that objects in the library cover the observed range of mid-infrared colors of known AGNs. The validity of the approach is demonstrated by matching the SEDs of a number of representative objects: Four Seyferts and two quasars for which we present new Herschel photometry, two radio galaxies, and one hyperluminous infrared galaxy. Strikingly, for the five luminous objects we find that pure AGN models fit the SED without needing to postulate starburst activity. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.The SED

  5. Is Black Hole Growth a Universal Process? Exploring Selection Effects in Measurements of AGN Accretion Rates and Host Galaxies.

    Science.gov (United States)

    Jones, Mackenzie

    2018-01-01

    At the center of essentially every massive galaxy is a monstrous black hole producing luminous radiation driven by the accretion of gas. By observing these active galactic nuclei (AGN) we may trace the growth of black holes across cosmic time. However, our knowledge of the full underlying AGN population is hindered by complex observational biases. My research aims to untangle these biases by using a novel approach to simulate the impact of selection effects on multiwavelength observations.The most statistically powerful studies of AGN to date come from optical spectroscopic surveys, with some reporting a complex relationship between AGN accretion rates and host galaxy characteristics. However, the optical waveband can be strongly influenced by selection effects and dilution from host galaxy star formation. I have shown that accounting for selection effects, the Eddington ratio distribution for optically-selected AGN is consistent with a broad power-law, as seen in the X-rays (Jones et al. 2016). This suggests that a universal Eddington ratio distribution may be enough to describe the full multiwavelength AGN population.Building on these results, I have expanded a semi-numerical galaxy formation simulation to include this straightforward prescription for AGN accretion and explicitly model selection effects. I have found that a simple model for AGN accretion can broadly reproduce the host galaxies and halos of X-ray AGN, and that different AGN selection techniques yield samples with very different host galaxy properties (Jones et al. 2017). Finally, I will discuss the capabilities of this simulation to build synthetic multiwavelength SEDs in order to explore what AGN populations would be detected with the next generation of observatories. This research is supported by a NASA Jenkins Graduate Fellowship under grant no. NNX15AU32H.

  6. Probing the Gas Fueling and Outflows in Nearby AGN with ALMA

    Energy Technology Data Exchange (ETDEWEB)

    Audibert, Anelise [Observatoire de Paris, LERMA, Centre National de la Recherche Scientifique, PSL University, Sorbonne University, UPMC, Paris (France); Combes, Françoise [Observatoire de Paris, LERMA, Centre National de la Recherche Scientifique, PSL University, Sorbonne University, UPMC, Paris (France); College de France, Paris (France); García-Burillo, Santiago [Observatorio Astronómico Nacional, Observatorio de Madrid, Madrid (Spain); Salomé, Philippe, E-mail: anelise.audibert@obspm.fr [Observatoire de Paris, LERMA, Centre National de la Recherche Scientifique, PSL University, Sorbonne University, UPMC, Paris (France)

    2017-12-12

    Feeding and feedback in AGN play a very important role to gain a proper understanding of galaxy formation and evolution. The interaction between activity mechanisms in the nucleus and its influence in the host galaxy are related to the physical processes involved in feedback and the gas fueling of the black hole. The discovery of many massive molecular outflows in the last few years have been promoting the idea that winds may be major actors in sweeping the gas out of galaxies. Also, the widely observed winds from the central regions of AGN are promising candidates to explain the scaling relations (e.g., the black hole-bulge mass relation, BH accretion rate tracking the star formation history) under the AGN feedback scenario. Out goal is to probe these phenomena through the kinematic and morphology of the gas inside the central kpc in nearby AGN. This has recently been possible due to the unprecedented ALMA spatial resolution and sensitivity. We present results on NGC7213 and NGC1808, the latter is part of a new ALMA follow-up of the NuGa project, a previous high-resolution (0.5–1″) CO survey of low luminosity AGN performed with the IRAM PdBI.

  7. DISENTANGLING AGN AND STAR FORMATION ACTIVITY AT HIGH REDSHIFT USING HUBBLE SPACE TELESCOPE GRISM SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    Bridge, Joanna S.; Zeimann, Gregory R.; Trump, Jonathan R.; Gronwall, Caryl; Ciardullo, Robin; Fox, Derek; Schneider, Donald P., E-mail: jsbridge@psu.edu [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2016-08-01

    Differentiating between active galactic nucleus (AGN) activity and star formation in z ∼ 2 galaxies is difficult because traditional methods, such as line-ratio diagnostics, change with redshift, while multi-wavelength methods (X-ray, radio, IR) are sensitive to only the brightest AGNs. We have developed a new method for spatially resolving emission lines using the Hubble Space Telescope /Wide Field Camera 3 G141 grism spectra and quantifying AGN activity through the spatial gradient of the [O iii]/H β line ratio. Through detailed simulations, we show that our novel line-ratio gradient approach identifies ∼40% more low-mass and obscured AGNs than obtained by classical methods. Based on our simulations, we developed a relationship that maps the stellar mass, star formation rate, and measured [O iii]/H β gradient to the AGN Eddington ratio. We apply our technique to previously studied stacked samples of galaxies at z ∼ 2 and find that our results are consistent with these studies. This gradient method will also be able to inform other areas of galaxy evolution science, such as inside-out quenching and metallicity gradients, and will be widely applicable to future spatially resolved James Webb Space Telescope data.

  8. Simultaneous Chandra and NuSTAR Observations of the Highly Obscured AGN Candidate in NGC660.

    Science.gov (United States)

    Annuar, Ady

    2014-09-01

    We are using NuSTAR to undertake a detailed investigation of the obscured AGN population at D<15Mpc. Our latest target is NGC660 where the presence of an AGN has been ambiguous. However, recently it was observed to undergo a radio outburst which reveals a bright continuum source (Argo et al. 2015), coincident with Chandra 2-8 keV emission from one of the three point sources near the nucleus (<5"). This confirms and pinpoints the X-ray position of the AGN. Comparisons of the Chandra flux with the radio emission and other multiwavelength luminosity indicators indicate that the X-ray flux is suppressed, suggesting that it is absorbed by a high column of gas. A NuSTAR observation for this object has been scheduled as part of our program. The requested Chandra observation is essential to unambiguously constrain the AGN and isolate it from other sources at <8 keV. When combined with NuSTAR, we will then be able to accurately characterise the 0.5-30 keV spectrum of the AGN for the first time.

  9. Search for neutrinos from TANAMI observed AGN using Fermi lightcurves wit ANTARES

    International Nuclear Information System (INIS)

    Fehn, Kerstin

    2015-01-01

    Active galactic nuclei (AGN) are promising candidates for hadronic acceleration. The combination of radio, gamma ray and neutrino data should give information on their properties, especially concerning the sources of the high-energetic cosmic rays. Assuming a temporal correlation of gamma and neutrino emission in AGN the background of neutrino telescopes can be reduced using gamma ray lightcurves. Thereby the sensitivity for discovering cosmic neutrino sources is enhanced. In the present work a stacked search for a group of AGN with the ANTARES neutrino telescope in the Mediterranean is presented. The selection of AGN is based on the source sample of TANAMI, a multiwavelength observation program (radio to gamma rays) of extragalactic jets southerly of -30 declination. In the analysis lightcurves of the gamma satellite Fermi are used. In an unbinned maximum likelihood approach the test statistic in the background only case and in the signal and background case is determined. For the investigated 10% of data of ANTARES within the measurement time between 01.09.2008 and 30.07.2012 no significant excess is observed. So on the total flux of the AGN of the stacked search an upper limit can be set.

  10. Correlating The Star Formation Histories Of MaNGA Galaxies With Their Past AGN Activity

    Science.gov (United States)

    Gonzalez Ortiz, Andrea

    2017-01-01

    We investigate active galactic nuclei (AGN) as a primary mechanism affecting star formation in MaNGA galaxies. Using the Pipe3D code, we modeled the stellar population from MaNGA spectra and derived the star formation histories of 53 AGN host galaxies. We seek to compare the star formation histories of the host galaxies of AGN with the ages of their radio lobes to better understand the role of AGN feedback in the star formation histories of MaNGA galaxies. MaNGA (Mapping Nearby Galaxies at APO) is one of the three core programs in the fourth generation Sloan Digital Sky Survey(SDSS). MaNGA will investigate the internal kinematics of nearly 10,000 local galaxies through dithered observations using fiber integral field units (IFUs) that vary in diameter from 12" (19 fibers) to 32" (127 fibers). In this poster, we present initial results on the star formation histories of MaNGA AGN host galaxies. This work was supported by the SDSS Research Experience for Undergraduates program, which is funded by a grant from Sloan Foundation to the Astrophysical Research Consortium.

  11. DISENTANGLING AGN AND STAR FORMATION ACTIVITY AT HIGH REDSHIFT USING HUBBLE SPACE TELESCOPE GRISM SPECTROSCOPY

    International Nuclear Information System (INIS)

    Bridge, Joanna S.; Zeimann, Gregory R.; Trump, Jonathan R.; Gronwall, Caryl; Ciardullo, Robin; Fox, Derek; Schneider, Donald P.

    2016-01-01

    Differentiating between active galactic nucleus (AGN) activity and star formation in z ∼ 2 galaxies is difficult because traditional methods, such as line-ratio diagnostics, change with redshift, while multi-wavelength methods (X-ray, radio, IR) are sensitive to only the brightest AGNs. We have developed a new method for spatially resolving emission lines using the Hubble Space Telescope /Wide Field Camera 3 G141 grism spectra and quantifying AGN activity through the spatial gradient of the [O iii]/H β line ratio. Through detailed simulations, we show that our novel line-ratio gradient approach identifies ∼40% more low-mass and obscured AGNs than obtained by classical methods. Based on our simulations, we developed a relationship that maps the stellar mass, star formation rate, and measured [O iii]/H β gradient to the AGN Eddington ratio. We apply our technique to previously studied stacked samples of galaxies at z ∼ 2 and find that our results are consistent with these studies. This gradient method will also be able to inform other areas of galaxy evolution science, such as inside-out quenching and metallicity gradients, and will be widely applicable to future spatially resolved James Webb Space Telescope data.

  12. Probing the gas fuelling and outflows in nearby AGN with ALMA

    Science.gov (United States)

    Audibert, Anelise; Combes, Françoise; García-Burillo, Santiago; Salomé, Philippe

    2017-12-01

    Feeding and feedback in AGN play a very important role to gain a proper understanding of galaxy formation and evolution. The interaction between activity mechanisms in the nucleus and its influence in the host galaxy are related to the physical processes involved in feedback and the gas fuelling of the black hole. The discovery of many massive molecular outflows in the last few years have been promoting the idea that winds may be major actors in sweeping the gas out of galaxies. Also, the widely observed winds from the central regions of AGN are promising candidates to explain the scaling relations (e.g. the black hole-bulge mass relation, BH accretion rate tracking the star formation history) under the AGN feedback scenario. Out goal is to probe these phenomena through the kinematic and morphology of the gas inside the central kpc in nearby AGN. This has recently been possible due to the unprecedented ALMA spatial resolution and sensitivity. We present results on NGC7213 and NGC1808, the latter is part of a new ALMA follow-up of the NuGa project, a previous high-resolution (0.5-1”) CO survey of low luminosity AGN performed with the IRAM PdBI.

  13. Probing the Gas Fueling and Outflows in Nearby AGN with ALMA

    Directory of Open Access Journals (Sweden)

    Anelise Audibert

    2017-12-01

    Full Text Available Feeding and feedback in AGN play a very important role to gain a proper understanding of galaxy formation and evolution. The interaction between activity mechanisms in the nucleus and its influence in the host galaxy are related to the physical processes involved in feedback and the gas fueling of the black hole. The discovery of many massive molecular outflows in the last few years have been promoting the idea that winds may be major actors in sweeping the gas out of galaxies. Also, the widely observed winds from the central regions of AGN are promising candidates to explain the scaling relations (e.g., the black hole-bulge mass relation, BH accretion rate tracking the star formation history under the AGN feedback scenario. Out goal is to probe these phenomena through the kinematic and morphology of the gas inside the central kpc in nearby AGN. This has recently been possible due to the unprecedented ALMA spatial resolution and sensitivity. We present results on NGC7213 and NGC1808, the latter is part of a new ALMA follow-up of the NuGa project, a previous high-resolution (0.5–1″ CO survey of low luminosity AGN performed with the IRAM PdBI.

  14. Standard Model festival

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1987-10-15

    The 'Standard Model' of modern particle physics, with the quantum chromodynamics (QCD) theory of inter-quark forces superimposed on the unified electroweak picture, is still unchallenged, but it is not the end of physics. This was the message at the big International Symposium on Lepton and Photon Interactions at High Energies, held in Hamburg from 27-31 July.

  15. Standard Model festival

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    The 'Standard Model' of modern particle physics, with the quantum chromodynamics (QCD) theory of inter-quark forces superimposed on the unified electroweak picture, is still unchallenged, but it is not the end of physics. This was the message at the big International Symposium on Lepton and Photon Interactions at High Energies, held in Hamburg from 27-31 July

  16. Unified Medical Language System (UMLS)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The UMLS integrates and distributes key terminology, classification and coding standards, and associated resources to promote creation of more effective and...

  17. Unified microprocessor CAMAC module for preliminary data processing

    International Nuclear Information System (INIS)

    Zaushitsin, V.L.; Kulik, O.V.; Repin, V.M.

    1984-01-01

    The UP-80 unified active module is described. It is made in the CAMAC standard on the base of the K580IK80 microprocessor allowing to increase the rate of large-volume experimental spectroscopic data processing by an order. Loading of 5 different programs for data processing is possible. Data from the operative storage with 1K capacity (8 bits) are recorded and read out trhough the CAMAC line (the regime of unit exchange is possible) or through the joint of the external line

  18. Polarization and Structure of Relativistic Parsec-Scale AGN Jets

    International Nuclear Information System (INIS)

    Lyutikov, M

    2004-01-01

    mildly relativistic jets, when a counter jet can be seen, the polarization of the counter jet is preferentially orthogonal to the axis, unless the jet is strongly dominated by the toroidal magnetic field in its rest frame. (6) For resolved jets, the polarization pattern is not symmetric with respect to jet axis. Under certain conditions, this can be used to deduce the direction of the spin of the central object (black hole or disk), whether it is aligned or anti-aligned with the jet axis. (7) In resolved ''cylindrical shell'' type jets, the central parts of the jet are polarized along the axis, while the outer parts are polarized orthogonal to it, in accordance with observations. We conclude that large-scale magnetic fields can explain the salient polarization properties of parsec-scale AGN jets. Since the typical degrees of polarization are (le) 15%, the emitting parts of the jets must have comparable rest-frame toroidal and poloidal fields. In this case, most relativistic jets are strongly dominated by the toroidal magnetic field component in the observer's frame, B φ /B z ∼ Λ. We also discuss the possibility that relativistic AGN jets may be electromagnetically (Poynting flux) dominated. In this case, dissipation of the toroidal magnetic field (and not fluid shocks) may be responsible for particle acceleration

  19. Benchmarking and Evaluating Unified Memory for OpenMP GPU Offloading

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Alok [Stony Brook Univ., Stony Brook, NY (United States); Li, Lingda [Brookhaven National Lab. (BNL), Upton, NY (United States); Kong, Martin [Brookhaven National Lab. (BNL), Upton, NY (United States); Finkel, Hal [Argonne National Lab. (ANL), Argonne, IL (United States); Chapman, Barbara [Stony Brook Univ., Stony Brook, NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-01-01

    Here, the latest OpenMP standard offers automatic device offloading capabilities which facilitate GPU programming. Despite this, there remain many challenges. One of these is the unified memory feature introduced in recent GPUs. GPUs in current and future HPC systems have enhanced support for unified memory space. In such systems, CPU and GPU can access each other's memory transparently, that is, the data movement is managed automatically by the underlying system software and hardware. Memory over subscription is also possible in these systems. However, there is a significant lack of knowledge about how this mechanism will perform, and how programmers should use it. We have modified several benchmarks codes, in the Rodinia benchmark suite, to study the behavior of OpenMP accelerator extensions and have used them to explore the impact of unified memory in an OpenMP context. We moreover modified the open source LLVM compiler to allow OpenMP programs to exploit unified memory. The results of our evaluation reveal that, while the performance of unified memory is comparable with that of normal GPU offloading for benchmarks with little data reuse, it suffers from significant overhead when GPU memory is over subcribed for benchmarks with large amount of data reuse. Based on these results, we provide several guidelines for programmers to achieve better performance with unified memory.

  20. RAiSE II: resolved spectral evolution in radio AGN

    Science.gov (United States)

    Turner, Ross J.; Rogers, Jonathan G.; Shabala, Stanislav S.; Krause, Martin G. H.

    2018-01-01

    The active galactic nuclei (AGN) lobe radio luminosities modelled in hydrodynamical simulations and most analytical models do not address the redistribution of the electron energies due to adiabatic expansion, synchrotron radiation and inverse-Compton scattering of cosmic microwave background photons. We present a synchrotron emissivity model for resolved sources that includes a full treatment of the loss mechanisms spatially across the lobe, and apply it to a dynamical radio source model with known pressure and volume expansion rates. The bulk flow and dispersion of discrete electron packets is represented by tracer fields in hydrodynamical simulations; we show that the mixing of different aged electrons strongly affects the spectrum at each point of the radio map in high-powered Fanaroff & Riley type II (FR-II) sources. The inclusion of this mixing leads to a factor of a few discrepancy between the spectral age measured using impulsive injection models (e.g. JP model) and the dynamical age. The observable properties of radio sources are predicted to be strongly frequency dependent: FR-II lobes are expected to appear more elongated at higher frequencies, while jetted FR-I sources appear less extended. The emerging FR0 class of radio sources, comprising gigahertz peaked and compact steep spectrum sources, can potentially be explained by a population of low-powered FR-Is. The extended emission from such sources is shown to be undetectable for objects within a few orders of magnitude of the survey detection limit and to not contribute to the curvature of the radio spectral energy distribution.

  1. The COS-AGN survey: Revealing the nature of circum-galactic gas around hosts of active galactic nuclei

    Science.gov (United States)

    Berg, Trystyn A. M.; Ellison, Sara L.; Tumlinson, Jason; Oppenheimer, Benjamin D.; Horton, Ryan; Bordoloi, Rongmon; Schaye, Joop

    2018-04-01

    Active galactic nuclei (AGN) are thought to play a critical role in shaping galaxies, but their effect on the circumgalactic medium (CGM) is not well studied. We present results from the COS-AGN survey: 19 quasar sightlines that probe the CGM of 20 optically-selected AGN host galaxies with impact parameters 80 frame equivalent widths EW≥124 mÅ) whilst many of the metal ions are not detected in individual sightlines. A sightline-by-sightline comparison between COS-AGN and the control sample yields no significant difference in EW distribution. However, stacked spectra of the COS-AGN and control samples show significant (>3σ) enhancements in the EW of both Siiii And Lyα at impact parameters >164 kpc by a factor of +0.45 ± 0.05 dex and >+0.75 dex respectively. The lack of detections of both high-ionization species near the AGN and strong kinematic offsets between the absorption systemic galaxy redshifts indicates that neither the AGN's ionization nor its outflows are the origin of these differences. Instead, we suggest the observed differences could result from either AGN hosts residing in haloes with intrinsically distinct gas properties, or that their CGM has been affected by a previous event, such as a starburst, which may also have fuelled the nuclear activity.

  2. An Orientation-Based Unification of Young Jetted AGN: The Case of 3C 286

    Energy Technology Data Exchange (ETDEWEB)

    Berton, Marco [Dipartimento di Fisica e Astronomia “G. Galilei,” Università di Padova, Padova (Italy); Brera Astronomical Observatory (INAF), Merate (Italy); Foschini, Luigi; Caccianiga, Alessandro [Brera Astronomical Observatory (INAF), Merate (Italy); Ciroi, Stefano [Dipartimento di Fisica e Astronomia “G. Galilei,” Università di Padova, Padova (Italy); Congiu, Enrico [Dipartimento di Fisica e Astronomia “G. Galilei,” Università di Padova, Padova (Italy); Brera Astronomical Observatory (INAF), Merate (Italy); Cracco, Valentina; Frezzato, Michele; La Mura, Giovanni; Rafanelli, Piero, E-mail: marco.berton@unipd.it [Dipartimento di Fisica e Astronomia “G. Galilei,” Università di Padova, Padova (Italy)

    2017-07-25

    In recent years, the old paradigm according to which only high-mass black holes can launch powerful relativistic jets in active galactic nuclei (AGN) has begun to crumble. The discovery of γ-rays coming from narrow-line Seyfert 1 galaxies (NLS1s), usually considered young and growing AGN harboring a central black hole with mass typically lower than 10{sup 8} M{sub ⊙}, indicated that also these low-mass AGN can produce powerful relativistic jets. The search for parent population of γ-ray emitting NLS1s revealed their connection with compact steep-spectrum sources (CSS). In this proceeding we present a review of the current knowledge of these sources, we present the new important case of 3C 286, classified here for the fist time as NLS1, and we finally provide a tentative orientation based unification of NLS1s and CSS sources.

  3. The Role of Turbulence in AGN Self-Regulation in Galaxy Clusters

    International Nuclear Information System (INIS)

    Scannapieco, Evan; Brueggen, Marcus

    2009-01-01

    Cool cores of galaxy clusters are thought to be heated by low-power active galactic nuclei (AGN), whose accretion is regulated by feedback. However, the interaction between the hot gas ejected by the AGN and the ambient intracluster medium is extremely difficult to simulate, as it involves a wide range of spatial scales and gas that is Rayleigh-Taylor (RT) unstable. Here we use a subgrid model for RT-driven turbulence to overcome these problems and present the first observationally-consistent hydrodynamical simulations of AGN self-regulation in galaxy clusters. For a wide range of parameter choices the cluster in our three-dimensional simulations regulates itself for at least several 10 9 years. Heating balances cooling through a string of outbreaks with a typical recurrence time of ≅80 Myrs, a timescale that depends only on the global cluster properties.

  4. An Orientation-Based Unification of Young Jetted AGN: The Case of 3C 286

    International Nuclear Information System (INIS)

    Berton, Marco; Foschini, Luigi; Caccianiga, Alessandro; Ciroi, Stefano; Congiu, Enrico; Cracco, Valentina; Frezzato, Michele; La Mura, Giovanni; Rafanelli, Piero

    2017-01-01

    In recent years, the old paradigm according to which only high-mass black holes can launch powerful relativistic jets in active galactic nuclei (AGN) has begun to crumble. The discovery of γ-rays coming from narrow-line Seyfert 1 galaxies (NLS1s), usually considered young and growing AGN harboring a central black hole with mass typically lower than 10 8 M ⊙ , indicated that also these low-mass AGN can produce powerful relativistic jets. The search for parent population of γ-ray emitting NLS1s revealed their connection with compact steep-spectrum sources (CSS). In this proceeding we present a review of the current knowledge of these sources, we present the new important case of 3C 286, classified here for the fist time as NLS1, and we finally provide a tentative orientation based unification of NLS1s and CSS sources.

  5. AGN Obscuration Through Dusty Infrared Dominated Flows. II. Multidimensional, Radiation-Hydrodynamics Modeling

    Science.gov (United States)

    Dorodnitsyn, Anton; Kallman, Tim; Bisno\\vatyiI-Kogan, Gennadyi

    2011-01-01

    We explore a detailed model in which the active galactic nucleus (AGN) obscuration results from the extinction of AGN radiation in a global ow driven by the pressure of infrared radiation on dust grains. We assume that external illumination by UV and soft X-rays of the dusty gas located at approximately 1pc away from the supermassive black hole is followed by a conversion of such radiation into IR. Using 2.5D, time-dependent radiation hydrodynamics simulations in a ux-limited di usion approximation we nd that the external illumination can support a geometrically thick obscuration via out ows driven by infrared radiation pressure in AGN with luminosities greater than 0:05 L(sub edd) and Compton optical depth, Tau(sub T) approx > & 1.

  6. Co-existence of two plasma phases in solar and AGN coronas

    Directory of Open Access Journals (Sweden)

    Kubičela A.

    1998-01-01

    Full Text Available Here we have juxtaposed two distant cosmic locations of the Sun and AGN where neutral hydrogen appears in a close connection with hot coronas. Besides the solar photosphere, chromosphere and prominences where the presence of neutral hydrogen is well established, its emission quite high in hot solar corona is still puzzling. Some of earlier observations where Hα emission in solar corona was detected in eclipse and in daily coronagraphic observations are reviewed. A proper theoretical explanation of this cold chromospheric-type emission in the hot corona does not exist yet. On the other side, a similar emission of hydrogen lines is present in Active Galactic Nuclei (AGNs. Much research work is currently being done in this field. We outline some of the concepts of the AGN structure prevailing in the astrophysics today.

  7. Type 2 Active Galactic Nuclei with Double-peaked [O III] Lines. II. Single AGNs with Complex Narrow-line Region Kinematics are More Common than Binary AGNs

    Science.gov (United States)

    Shen, Yue; Liu, Xin; Greene, Jenny E.; Strauss, Michael A.

    2011-07-01

    Approximately 1% of low-redshift (z interpreted as either due to kinematics, such as biconical outflows and/or disk rotation of the narrow line region (NLR) around single black holes, or due to the relative motion of two distinct NLRs in a merging pair of AGNs. Here, we report follow-up near-infrared (NIR) imaging and optical slit spectroscopy of 31 double-peaked [O III] type 2 AGNs drawn from the Sloan Digital Sky Survey (SDSS) parent sample presented in Liu et al. The NIR imaging traces the old stellar population in each galaxy, while the optical slit spectroscopy traces the NLR gas. These data reveal a mixture of origins for the double-peaked feature. Roughly 10% of our objects are best explained by binary AGNs at (projected) kpc-scale separations, where two stellar components with spatially coincident NLRs are seen. ~50% of our objects have [O III] emission offset by a few kpc, corresponding to the two velocity components seen in the SDSS spectra, but there are no spatially coincident double stellar components seen in the NIR imaging. For those objects with sufficiently high-quality slit spectra, we see velocity and/or velocity dispersion gradients in [O III] emission, suggestive of the kinematic signatures of a single NLR. The remaining ~40% of our objects are ambiguous and will need higher spatial resolution observations to distinguish between the two scenarios. Our observations therefore favor the kinematics scenario with a single AGN for the majority of these double-peaked [O III] type 2 AGNs. We emphasize the importance of combining imaging and slit spectroscopy in identifying kpc-scale binary AGNs, i.e., in no cases does one of these alone allow an unambiguous identification. We estimate that ~0.5%-2.5% of the z ~ 150 km s-1. Based in part on observations obtained with the 6.5 m Magellan telescopes located at Las Campanas Observatory, Chile, and with the Apache Point Observatory 3.5 m telescope, which is owned and operated by the Astrophysical Research

  8. Argument for a non-standard broad-line region

    International Nuclear Information System (INIS)

    Collin, S.

    1987-01-01

    The region emitting the broad lines (BLR) in quasars and AGN has a ''Standard Status''. It is shown that this status raises strong problems concerning the energetic budget and the thermal state of the BLR. A possible solution is proposed [fr

  9. Transcription regulation of the alpha-glucanase gene agn1 by cell separation transcription factor Ace2p in fission yeast

    NARCIS (Netherlands)

    Dekker, Nick; de Haan, Annett; Hochstenbach, Frans

    2006-01-01

    During the final stage of the cell division cycle in the fission yeast Schizosaccharomyces pombe, transcription factor Ace2p activates expression of genes involved in the separation of newly formed daughter cells, such as agn1+, which encodes the alpha-glucanase Agn1p. The agn1 promoter contains

  10. Obscured AGN at z similar to 1 from the zCOSMOS-Bright Survey : I. Selection and optical properties of a [Ne v]-selected sample

    NARCIS (Netherlands)

    Mignoli, M.; Vignali, C.; Gilli, R.; Comastri, A.; Zamorani, G.; Bolzonella, M.; Bongiorno, A.; Lamareille, F.; Nair, P.; Pozzetti, L.; Lilly, S. J.; Carollo, C. M.; Contini, T.; Kneib, J. -P.; Le Fevre, O.; Mainieri, V.; Renzini, A.; Scodeggio, M.; Bardelli, S.; Caputi, K.; Cucciati, O.; de la Torre, S.; de Ravel, L.; Franzetti, P.; Garilli, B.; Iovino, A.; Kampczyk, P.; Knobel, C.; Kovac, K.; Le Borgne, J. -F.; Le Brun, V.; Maier, C.; Pello, R.; Peng, Y.; Montero, E. Perez; Presotto, V.; Silverman, J. D.; Tanaka, M.; Tasca, L.; Tresse, L.; Vergani, D.; Zucca, E.; Bordoloi, R.; Cappi, A.; Cimatti, A.; Koekemoer, A. M.; McCracken, H. J.; Moresco, M.; Welikala, N.

    Aims. The application of multi-wavelength selection techniques is essential for obtaining a complete and unbiased census of active galactic nuclei (AGN). We present here a method for selecting z similar to 1 obscured AGN from optical spectroscopic surveys. Methods. A sample of 94 narrow-line AGN

  11. The infrared medium-deep survey. II. How to trigger radio AGNs? Hints from their environments

    Energy Technology Data Exchange (ETDEWEB)

    Karouzos, Marios; Im, Myungshin; Kim, Jae-Woo; Lee, Seong-Kook; Jeon, Yiseul; Choi, Changsu; Hong, Jueun; Hyun, Minhee; Jun, Hyunsung David; Kim, Dohyeong; Kim, Yongjung; Kim, Ji Hoon; Kim, Duho; Park, Won-Kee; Taak, Yoon Chan; Yoon, Yongmin [CEOU—Astronomy Program, Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Chapman, Scott [Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia (Canada); Pak, Soojong [School of Space Research, Kyung Hee University, Yongin-si, Gyeonggi-do 446-701 (Korea, Republic of); Edge, Alastair, E-mail: mkarouzos@astro.snu.ac.kr [Department of Physics, University of Durham, South Road, Durham, DH1 3LE (United Kingdom)

    2014-12-10

    Activity at the centers of galaxies, during which the central supermassive black hole is accreting material, is nowadays accepted to be rather ubiquitous and most probably a phase of every galaxy's evolution. It has been suggested that galactic mergers and interactions may be the culprits behind the triggering of nuclear activity. We use near-infrared data from the new Infrared Medium-Deep Survey and the Deep eXtragalactic Survey of the VIMOS-SA22 field and radio data at 1.4 GHz from the FIRST survey and a deep Very Large Array survey to study the environments of radio active galactic nuclei (AGNs) over an area of ∼25 deg{sup 2} and down to a radio flux limit of 0.1 mJy and a J-band magnitude of 23 mag AB. Radio AGNs are predominantly found in environments similar to those of control galaxies at similar redshift, J-band magnitude, and (M{sub u} – M{sub r} ) rest-frame color. However, a subpopulation of radio AGNs is found in environments up to 100 times denser than their control sources. We thus preclude merging as the dominant triggering mechanism of radio AGNs. By fitting the broadband spectral energy distribution of radio AGNs in the least and most dense environments, we find that those in the least dense environments show higher radio-loudness, higher star formation efficiencies, and higher accretion rates, typical of the so-called high-excitation radio AGNs. These differences tend to disappear at z > 1. We interpret our results in terms of a different triggering mechanism for these sources that is driven by mass loss through winds of young stars created during the observed ongoing star formation.

  12. A tale of two feedbacks: Star formation in the host galaxies of radio AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Karouzos, Marios; Im, Myungshin; Jeon, Yiseul; Kim, Ji Hoon [CEOU-Astronomy Program, Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul (Korea, Republic of); Trichas, Markos [Airbus Defence and Space, Gunnels Wood Road, Stevenage SG1 2AS (United Kingdom); Goto, Tomo [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Malkan, Matt [Division of Astronomy and Astrophysics, 3-714 UCLA, CA 90095-1547 (United States); Ruiz, Angel [Inter-University Centre for Astronomy and Astrophysics (IUCAA), Post Bag 4, Ganeshkhind, 411 007 Pune (India); Lee, Hyung Mok; Kim, Seong Jin [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul (Korea, Republic of); Oi, Nagisa; Matsuhara, Hideo; Takagi, Toshinobu; Murata, K.; Wada, Takehiko; Wada, Kensuke [Institute of Space and Astronautical Science, JAXA, Yoshino-dai 3-1-1, Sagamihara, Kanagawa 229-8510 (Japan); Shim, Hyunjin [Department of Earth Science Education, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Hanami, Hitoshi [Physics Section, Faculty of Humanities, Iwate University, Ueda 3 chome, 18-34 Morioka, Morioka, Iwate 020-8550 (Japan); Serjeant, Stephen; White, Glenn J., E-mail: mkarouzos@astro.snu.ac.kr [Department of Physics and Astronomy, The Open University, Walton Hall, Milton Keynes (United Kingdom); and others

    2014-04-01

    Several lines of argument support the existence of a link between activity at the nuclei of galaxies, in the form of an accreting supermassive black hole, and star formation activity in these galaxies. Radio jets have long been argued to be an ideal mechanism that allows active galactic nuclei (AGNs) to interact with their host galaxies and affect star formation. We use a sample of radio sources in the North Ecliptic Pole (NEP) field to study the nature of this putative link, by means of spectral energy distribution (SED) fitting. We employ the excellent spectral coverage of the AKARI infrared space telescope and the rich ancillary data available in the NEP to build SEDs extending from UV to far-IR wavelengths. We find a significant AGN component in our sample of relatively faint radio sources (AGN component and that of star formation in the host galaxy, independent of the radio luminosity. In contrast, for narrow redshift and AGN luminosity ranges, we find that increasing radio luminosity leads to a decrease in the specific star formation rate. The most radio-loud AGNs are found to lie on the main sequence of star formation for their respective redshifts. For the first time, we potentially see such a two-sided feedback process in the same sample. We discuss the possible suppression of star formation, but not total quenching, in systems with strong radio jets, that supports the maintenance nature of feedback from radio AGN jets.

  13. The Origin of Fast Molecular Outflows in Quasars: Molecule Formation in AGN-Driven Galactic Winds

    Science.gov (United States)

    Richings, Alexander James; Faucher-Giguere, Claude-Andre

    2017-07-01

    Observations of AGN host galaxies have detected fast molecular outflows, with velocities up to 1000 km s-1. However, the origin of these molecular outflows is currently unclear. One possibility is that they are formed from molecular gas that is swept up from the host galaxy by the AGN wind. However, previous studies have suggested that molecular clouds that are swept up by an AGN wind are unlikely to survive being accelerated to such high velocities. An alternative scenario is that molecules may form within the AGN wind material itself. We present a suite of 3D hydrodynamic simulations of an idealised AGN wind that we have run to explore this scenario. These simulations are coupled to a time-dependent chemical model to follow the creation and destruction of molecules, including H2, CO, OH and HCO+. We find that molecules do form within the wind, with molecular outflow rates up to 140 M⊙ yr-1 after 1 Myr. This is sensitive to the ambient ISM density, metallicity, and AGN luminosity. We also compute observable CO emission lines from these simulations using a radiative transfer code in post-processing. The CO-derived outflow rates are comparable to those seen in observations, although the maximum line of sight velocities are a factor ≍2 lower than observed. We find a CO (1-0) to H2 conversion factor of αCO = 0.15 M⊙ (K km s-1 pc2)-1 at solar metallicity, 5 times lower than is typically assumed in observations of such systems.

  14. The ΓX-L/LEdd relation in BAT AGN Spectroscopic Survey (BASS)

    Science.gov (United States)

    Trakhtenbrot, Benny; Ricci, Claudio; Koss, Michael; Schawinski, Kevin; Mushotzky, Richard; Ueda, Yoshihiro; Veilleux, Sylvain; Lamperti, Isabella; Oh, Kyuseok; Treister, Ezequiel; Stern, Daniel; Harrison, Fiona; Balokovic, Mislav

    2018-01-01

    We present a study of the relation between accretion rate (in terms of L/LEdd) and shape of the hard X-ray spectral energy distribution (namely the photon index Γx) for a large sample of over 200 hard X-ray-selected, low-redshift active galactic nuclei (AGNs), drawn from the Swift/BAT AGN Spectroscopic Survey (BASS). This includes 30 AGNs for which black hole mass (and therefore L/LEdd) is measured directly through masers, spatially resolved gas or stellar dynamics, or reverberation mapping. The high-quality and broad energy coverage of the data provided through BASS allow us to examine several alternative determinations of both Γx and L/LEdd. We find very weak correlation between Γx and L/LEdd for the BASS sample as a whole, with best-fitting relations that are considerably shallower than those reported in previous studies. Moreover, we find no corresponding correlations among the subsets of AGN with different MBH determination methodology, and in particular those AGN with direct or single-epoch MBH estimates. This latter finding is in contrast to several previous studies which focused on z > 0.5 broad-line AGN. We conclude that this tension can be partially accounted for if one adopts a simplified, power-law X-ray spectral model, combined with L/LEdd estimates that are based on the continuum emission and on single-epoch broad-line spectroscopy in the optical regime. Given these findings, we highlight the limitations of using Γx as a probe of supermassive black hole evolution in deep extragalactic X-ray surveys.

  15. FRESH ACTIVITY IN OLD SYSTEMS: RADIO AGNs IN FOSSIL GROUPS OF GALAXIES

    International Nuclear Information System (INIS)

    Hess, Kelley M.; Wilcots, Eric M.; Hartwick, Victoria L.

    2012-01-01

    We present the first systematic 1.4 GHz Very Large Array radio continuum survey of fossil galaxy group candidates. These are virialized systems believed to have assembled over a gigayear in the past through the merging of galaxy group members into a single, isolated, massive elliptical galaxy and featuring an extended hot X-ray halo. We use new photometric and spectroscopic data from Sloan Digital Sky Survey Data Release 7 to determine that three of the candidates are clearly not fossil groups. Of the remaining 30 candidates, 67% contain a radio-loud (L 1.4GHz > 10 23 W Hz –1 ) active galactic nucleus (AGN) at the center of their dominant elliptical galaxy. We find a weak correlation between the radio luminosity of the AGN and the X-ray luminosity of the halo suggesting that the AGN contributes to energy deposition into the intragroup medium. We only find a correlation between the radio and optical luminosity of the central elliptical galaxy when we include X-ray-selected, elliptically dominated non-fossil groups, indicating a weak relationship between AGN strength and the mass assembly history of the groups. The dominant elliptical galaxy of fossil groups is on average roughly an order of magnitude more luminous than normal group elliptical galaxies in optical, X-ray, and radio luminosities and our findings are consistent with previous results that the radio-loud fraction in elliptical galaxies is linked to the stellar mass of a population. The current level of activity in fossil groups suggests that AGN fueling continues long after the last major merger. We discuss several possibilities for fueling the AGN at the present epoch.

  16. Exploring the Connection Between Star Formation and AGN Activity in the Local Universe

    Science.gov (United States)

    LaMassa, Stephanie M.; Heckman. T. M.; Ptak, Andrew; Schiminovich, D.; O'Dowd, M.; Bertincourt, B.

    2012-01-01

    We study a combined sample of 264 star-forming, 51 composite, and 73 active galaxies using optical spectra from SDSS and mid-infrared (mid-IR) spectra from the Spitzer Infrared Spectrograph. We examine optical and mid-IR spectroscopic diagnostics that probe the amount of star formation and relative energetic con- tributions from star formation and an active galactic nucleus (AGN). Overall we find good agreement between optical and mid-IR diagnostics. Misclassifications of galaxies based on the SDSS spectra are rare despite the presence of dust obscuration. The luminosity of the [NeII] 12.8 micron emission-line is well correlated with the star formation rate (SFR) measured from the SDSS spectra, and this holds for the star forming, composite, and AGN-dominated systems. AGN show a clear excess of [NeIII] 15.6 micron emission relative to star forming and composite systems. We find good qualitative agreement between various parameters that probe the relative contributions of the AGN and star formation, including: the mid-IR spectral slope, the ratio of the [NeV] 14.3 micron to [NeII] micron 12.8 fluxes, the equivalent widths of the 7.7, 11.3, and 17 micron PAH features, and the optical "D" parameter which measures the distance a source lies from the locus of star forming galaxies in the optical BPT emission-line diagnostic diagram. We also consider the behavior of the three individual PAH features by examining how their flux ratios depend upon the degree of AGN-dominance. We find that the PAH 11.3 micron feature is significantly suppressed in the most AGN-dominated systems.

  17. A fragilidade das Instituições Sociais e o rompimento da Ética no filme Agnes de Deus.

    Directory of Open Access Journals (Sweden)

    Marco Antonio Palermo Moretto

    2015-04-01

    Full Text Available Research about the fragilities of the social institutions in the movie Agnes of God and the ethic and moral. There are a mistery in the story:a murder of the baby inside the convent.  The young nun, Agnes killed her baby and a psichiatrist. Dra. Martha Livingstone  begans a investigation since the childhood of Agnes until the crime. The presence of the Superior Mother, Mirian Ruth is important to the story. She is an administrator and protect Agnes in many situations. Such social institutions are showed as Family, Religion and the Justice. Methods are explained: questions and the hipnosis. Agnes has mistics experiences and reveal the conflict between cience and religion.

  18. Finding AGN in Deep X-ray Flux States with Swift

    OpenAIRE

    Grupe, Dirk; Komossa, S.; Bush, Mason; Pruett, Chelsea; Ernst, Sonny; Barber, Taylor; Carter, Jen; Schartel, Norbert; Rodriguez, Pedro; Santos-Lleó, Maria

    2015-01-01

    We report on our ongoing project of finding Active Galactic Nuclei (AGN) that go into deep X-ray flux states detected by Swift. Swift is performing an extensive study on the flux and spectral variability of AGN using Guest Investigator and team fill-in programs followed by triggering XMM_Newton for deeper follow-up observations. So far this program has been very successful and has led to a number of XMM-Newton follow up observations, including Mkn 335, PG 0844+349, and RX J2340.8-5329. Recent...

  19. Cosmological Evolution of the Central Engine in High-Luminosity, High-Accretion Rate AGN

    Directory of Open Access Journals (Sweden)

    Matteo Guainazzi

    2014-12-01

    Full Text Available In this paper I discuss the status of observational studies aiming at probing the cosmological evolution of the central engine in high-luminosity, high-accretion rate Active Galactic Nuclei (AGN. X-ray spectroscopic surveys, supported by extensive multi-wavelength coverage, indicate a remarkable invariance of the accretion disk plus corona system, and of their coupling up to redshifts z≈6. Furthermore, hard X-ray (E >10 keV surveys show that nearby Seyfert Galaxies share the same central engine notwithstanding their optical classication. These results suggest that the high-luminosity, high accretion rate quasar phase of AGN evolution is homogeneous over cosmological times.

  20. Identifying the subtle signatures of feedback from distant AGN using ALMA observations and the EAGLE hydrodynamical simulations

    Science.gov (United States)

    Scholtz, J.; Alexander, D. M.; Harrison, C. M.; Rosario, D. J.; McAlpine, S.; Mullaney, J. R.; Stanley, F.; Simpson, J.; Theuns, T.; Bower, R. G.; Hickox, R. C.; Santini, P.; Swinbank, A. M.

    2018-03-01

    We present sensitive 870 μm continuum measurements from our ALMA programmes of 114 X-ray selected active galactic nuclei (AGN) in the Chandra Deep Field-South and Cosmic Evolution Survey fields. We use these observations in combination with data from Spitzer and Herschel to construct a sample of 86 X-ray selected AGN, 63 with ALMA constraints at z = 1.5-3.2 with stellar mass >2 × 1010 M⊙. We constructed broad-band spectral energy distributions in the infrared band (8-1000 μm) and constrain star-formation rates (SFRs) uncontaminated by the AGN. Using a hierarchical Bayesian method that takes into account the information from upper limits, we fit SFR and specific SFR (sSFR) distributions. We explore these distributions as a function of both X-ray luminosity and stellar mass. We compare our measurements to two versions of the Evolution and Assembly of GaLaxies and their Environments (EAGLE) hydrodynamical simulations: the reference model with AGN feedback and the model without AGN. We find good agreement between the observations and that predicted by the EAGLE reference model for the modes and widths of the sSFR distributions as a function of both X-ray luminosity and stellar mass; however, we found that the EAGLE model without AGN feedback predicts a significantly narrower width when compared to the data. Overall, from the combination of the observations with the model predictions, we conclude that (1) even with AGN feedback, we expect no strong relationship between the sSFR distribution parameters and instantaneous AGN luminosity and (2) a signature of AGN feedback is a broad distribution of sSFRs for all galaxies (not just those hosting an AGN) with stellar masses above ≈1010 M⊙.

  1. Mid-IR Properties of an Unbiased AGN Sample of the Local Universe. 1; Emission-Line Diagnostics

    Science.gov (United States)

    Weaver, K. A.; Melendez, M.; Muhotzky, R. F.; Kraemer, S.; Engle, K.; Malumuth. E.; Tueller, J.; Markwardt, C.; Berghea, C. T.; Dudik, R. P.; hide

    2010-01-01

    \\Ve compare mid-IR emission-lines properties, from high-resolution Spitzer IRS spectra of a statistically-complete hard X-ray (14-195 keV) selected sample of nearby (z < 0.05) AGN detected by the Burst Alert Telescope (BAT) aboard Swift. The luminosity distribution for the mid-infrared emission-lines, [O IV] 25.89 microns, [Ne II] 12.81 microns, [Ne III] 15.56 microns and [Ne V] 14.32 microns, and hard X-ray continuum show no differences between Seyfert 1 and Seyfert 2 populations, although six newly discovered BAT AGNs are shown to be under-luminous in [O IV], most likely the result of dust extinction in the host galaxy. The overall tightness of the mid-infrared correlations and BAT luminosities suggests that the emission lines primarily arise in gas ionized by the AGN. We also compared the mid-IR emission-lines in the BAT AGNs with those from published studies of star-forming galaxies and LINERs. We found that the BAT AGN fall into a distinctive region when comparing the [Ne III]/[Ne II] and the [O IV]/[Ne III] quantities. From this we found that sources that have been previously classified in the mid-infrared/optical as AGN have smaller emission line ratios than those found for the BAT AGNs, suggesting that, in our X-ray selected sample, the AGN represents the main contribution to the observed line emission. Overall, we present a different set of emission line diagnostics to distinguish between AGN and star forming galaxies that can be used as a tool to find new AGN.

  2. A unifying energy-based approach to stability of power grids with market dynamics

    NARCIS (Netherlands)

    Stegink, Tjerk; De Persis, Claudio; van der Schaft, Arjan

    2017-01-01

    In this paper a unifying energy-based approach is provided to the modeling and stability analysis of power systems coupled with market dynamics. We consider a standard model of the power network with a third-order model for the synchronous generators involving voltage dynamics. By applying the

  3. Oasis in the desert: weakly broken parity in grand unified theories

    International Nuclear Information System (INIS)

    Senjanovic, G.

    1981-07-01

    A discussion of low energy parity restoration in simple grand unified theories, such as SO(10), is presented. The consistency of phenomenological requirements and unification constraints is emphasized and various predictions of the theory are stressed, in particular: substantially lighter W and Z bosons than in the standard model and increased stability of the proton with tau/sub p/ approx. = 10 38 years

  4. A unified transmission loss allocation method

    International Nuclear Information System (INIS)

    Ding, Qifeng; Abur, Ali

    2007-01-01

    A new unified method which allocates transmission losses either to buses in a pool market or to individual transactions in a bilateral contract market is presented in this paper. A detailed derivation of the method is given. A bus-loss matrix and a transaction-loss matrix are developed to show the interactions between bus injections and transactions. It is further demonstrated that the ''Physical-power-flow-based'' method can be obtained as an approximation of this unified approach under certain simplifying assumptions. Test systems are used to illustrate how the proposed method behaves under different possible scenarios. (author)

  5. Unifying distribution functions: some lesser known distributions.

    Science.gov (United States)

    Moya-Cessa, J R; Moya-Cessa, H; Berriel-Valdos, L R; Aguilar-Loreto, O; Barberis-Blostein, P

    2008-08-01

    We show that there is a way to unify distribution functions that describe simultaneously a classical signal in space and (spatial) frequency and position and momentum for a quantum system. Probably the most well known of them is the Wigner distribution function. We show how to unify functions of the Cohen class, Rihaczek's complex energy function, and Husimi and Glauber-Sudarshan distribution functions. We do this by showing how they may be obtained from ordered forms of creation and annihilation operators and by obtaining them in terms of expectation values in different eigenbases.

  6. Technical writing practically unified through industry

    Science.gov (United States)

    Houston, L. S.

    1981-01-01

    General background details in the development of a university level technical writing program, based upon the writing tasks of the student's occupations, are summarized. Objectives and methods for unifying the courses of study with the needs of industry are discussed. Four academic course divisions, Industries Technologies, in which preparation and training are offered are: Animal, Horticulture, Agriculture, and Agricultural Business. Occupational competence is cited as the main goal for these programs in which technical writing is to be practically unified through industry. Course descriptions are also provided.

  7. A simple way to improve AGN feedback prescription in SPH simulations

    Science.gov (United States)

    Zubovas, Kastytis; Bourne, Martin A.; Nayakshin, Sergei

    2016-03-01

    Active galactic nuclei (AGN) feedback is an important ingredient in galaxy evolution, however its treatment in numerical simulations is necessarily approximate, requiring subgrid prescriptions due to the dynamical range involved in the calculations. We present a suite of smoothed particle hydrodynamics simulations designed to showcase the importance of the choice of a particular subgrid prescription for AGN feedback. We concentrate on two approaches to treating wide-angle AGN outflows: thermal feedback, where thermal and kinetic energy is injected into the gas surrounding the supermassive black hole (SMBH) particle, and virtual particle feedback, where energy is carried by tracer particles radially away from the AGN. We show that the latter model produces a far more complex structure around the SMBH, which we argue is a more physically correct outcome. We suggest a simple improvement to the thermal feedback model - injecting the energy into a cone, rather than spherically symmetrically - and show that this markedly improves the agreement between the two prescriptions, without requiring any noticeable increase in the computational cost of the simulation.

  8. The contribution of unresolved radio-loud AGN to the extragalactic diffuse gamma-ray background

    DEFF Research Database (Denmark)

    Mucke, A.; Pohl, M.

    2000-01-01

    , and on the unification scheme of radio-loud AGN. According to this picture, blazars represent the beamed fraction of the Fanaroff-Riley radio galaxies (FR galaxies). The observed log N-log S distribution and redshift distribution of both FSRQs and BL Lacs constrain our model. Depending slightly on the evolutionary...

  9. The unification of powerful radio-loud AGN: the multi-wavelength balance

    NARCIS (Netherlands)

    Podigachoski, Pece; Barthel, Peter; Haas, Martin; Leipski, Christian; Wilkes, Belinda; Rocca-Volmerange, Brigitte; Drouart, Guillaume

    2016-01-01

    Powerful radio-loud AGN, by virtue of their optically-thin low-frequency radio emission, represent unique targets in orientation-based unification studies, and in searches for orientation indicators and orientation invariants. Central in these efforts is the landmark Third Cambridge Catalog of Radio

  10. Line Shape Variability in a Sample of AGN with Broad Lines

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... We give here a comparative review of the line shape variability in a sample of five type 1 AGNs, those with broad emission lines in their spectra, of the data obtained from the international long-term optical monitoring campaign coordinated by the Special Astrophysical Observatory of the Russian Academy ...

  11. IC 3639 - A new bona fide Compton thick AGN unveiled by NuSTAR

    DEFF Research Database (Denmark)

    Boorman, Peter G.; Gandhi, P.; Alexander, D.

    2016-01-01

    We analyse high-quality NuSTAR observations of the local (z = 0.011) Seyfert 2 active galactic nucleus (AGN) IC 3639, in conjunction with archival Suzaku and Chandra data. This provides the first broadband X-ray spectral analysis of the source, spanning nearly two decades in energy (0.5 -30 keV)....

  12. THE LICK AGN MONITORING PROJECT: PHOTOMETRIC LIGHT CURVES AND OPTICAL VARIABILITY CHARACTERISTICS

    International Nuclear Information System (INIS)

    Walsh, Jonelle L.; Bentz, Misty C.; Barth, Aaron J.; Minezaki, Takeo; Sakata, Yu; Yoshii, Yuzuru; Baliber, Nairn; Bennert, Vardha Nicola; Street, Rachel A.; Treu, Tommaso; Li Weidong; Filippenko, Alexei V.; Stern, Daniel; Brown, Timothy M.; Canalizo, Gabriela; Gates, Elinor L.; Greene, Jenny E.; Malkan, Matthew A.; Woo, Jong-Hak

    2009-01-01

    The Lick AGN Monitoring Project targeted 13 nearby Seyfert 1 galaxies with the intent of measuring the masses of their central black holes using reverberation mapping. The sample includes 12 galaxies selected to have black holes with masses roughly in the range 10 6 -10 7 M sun , as well as the well-studied active galactic nucleus (AGN) NGC 5548. In conjunction with a spectroscopic monitoring campaign, we obtained broadband B and V images on most nights from 2008 February through 2008 May. The imaging observations were carried out by four telescopes: the 0.76 m Katzman Automatic Imaging Telescope, the 2 m Multicolor Active Galactic Nuclei Monitoring telescope, the Palomar 60 inch (1.5 m) telescope, and the 0.80 m Tenagra II telescope. Having well-sampled light curves over the course of a few months is useful for obtaining the broad-line reverberation lag and black hole mass, and also allows us to examine the characteristics of the continuum variability. In this paper, we discuss the observational methods and the photometric measurements, and present the AGN continuum light curves. We measure various variability characteristics of each of the light curves. We do not detect any evidence for a time lag between the B- and V-band variations, and we do not find significant color variations for the AGNs in our sample.

  13. CAIXA: a catalogue of AGN in the XMM-Newton archive. III. Excess variance analysis

    NARCIS (Netherlands)

    Ponti, G.; Papadakis, I.; Bianchi, S.; Guainazzi, M.; Matt, G.; Uttley, P.; Bonilla, N.F.

    2012-01-01

    Context. We report on the results of the first XMM-Newton systematic "excess variance" study of all the radio quiet, X-ray un-obscured AGN. The entire sample consist of 161 sources observed by XMM-Newton for more than 10 ks in pointed observations, which is the largest sample used so far to study

  14. CAN AGN FEEDBACK BREAK THE SELF-SIMILARITY OF GALAXIES, GROUPS, AND CLUSTERS?

    Energy Technology Data Exchange (ETDEWEB)

    Gaspari, M. [Max Planck Institute for Astrophysics, Karl-Schwarzschild-Strasse 1, D-85741 Garching (Germany); Brighenti, F. [Astronomy Department, University of Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Temi, P. [Astrophysics Branch, NASA/Ames Research Center, MS 245-6, Moffett Field, CA 94035 (United States); Ettori, S., E-mail: mgaspari@mpa-garching.mpg.de [INAF, Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy)

    2014-03-01

    It is commonly thought that active galactic nucleus (AGN) feedback can break the self-similar scaling relations of galaxies, groups, and clusters. Using high-resolution three-dimensional hydrodynamic simulations, we isolate the impact of AGN feedback on the L {sub x}-T {sub x} relation, testing the two archetypal and common regimes, self-regulated mechanical feedback and a quasar thermal blast. We find that AGN feedback has severe difficulty in breaking the relation in a consistent way. The similarity breaking is directly linked to the gas evacuation within R {sub 500}, while the central cooling times are inversely proportional to the core density. Breaking self-similarity thus implies breaking the cool core, morphing all systems to non-cool-core objects, which is in clear contradiction with the observed data populated by several cool-core systems. Self-regulated feedback, which quenches cooling flows and preserves cool cores, prevents dramatic evacuation and similarity breaking at any scale; the relation scatter is also limited. The impulsive thermal blast can break the core-included L {sub x}-T {sub x} at T {sub 500} ≲ 1 keV, but substantially empties and overheats the halo, generating a perennial non-cool-core group, as experienced by cosmological simulations. Even with partial evacuation, massive systems remain overheated. We show that the action of purely AGN feedback is to lower the luminosity and heat the gas, perpendicular to the fit.

  15. AGN classification for X-ray sources in the 105 month Swift/BAT survey

    Science.gov (United States)

    Masetti, N.; Bassani, L.; Palazzi, E.; Malizia, A.; Stephen, J. B.; Ubertini, P.

    2018-03-01

    We here provide classifications for 8 hard X-ray sources listed as 'unknown AGN' in the 105 month Swift/BAT all-sky survey catalogue (Oh et al. 2018, ApJS, 235, 4). The corresponding optical spectra were extracted from the 6dF Galaxy Survey (Jones et al. 2009, MNRAS, 399, 683).

  16. IC 751: A New Changing Look AGN Discovered By NuSTAR

    DEFF Research Database (Denmark)

    Ricci, C.; Bauer, F. E.; Arevalo, P.

    2016-01-01

    We present results of five Nuclear Spectroscopic Telescope Array (NuSTAR) observations of the type 2 active galactic nucleus (AGN) in IC 751, three of which were performed simultaneously with XMM-Newton or Swift/X-Ray Telescope. We find that the nuclear X-ray source underwent a clear transition f...

  17. CAN AGN FEEDBACK BREAK THE SELF-SIMILARITY OF GALAXIES, GROUPS, AND CLUSTERS?

    International Nuclear Information System (INIS)

    Gaspari, M.; Brighenti, F.; Temi, P.; Ettori, S.

    2014-01-01

    It is commonly thought that active galactic nucleus (AGN) feedback can break the self-similar scaling relations of galaxies, groups, and clusters. Using high-resolution three-dimensional hydrodynamic simulations, we isolate the impact of AGN feedback on the L x -T x relation, testing the two archetypal and common regimes, self-regulated mechanical feedback and a quasar thermal blast. We find that AGN feedback has severe difficulty in breaking the relation in a consistent way. The similarity breaking is directly linked to the gas evacuation within R 500 , while the central cooling times are inversely proportional to the core density. Breaking self-similarity thus implies breaking the cool core, morphing all systems to non-cool-core objects, which is in clear contradiction with the observed data populated by several cool-core systems. Self-regulated feedback, which quenches cooling flows and preserves cool cores, prevents dramatic evacuation and similarity breaking at any scale; the relation scatter is also limited. The impulsive thermal blast can break the core-included L x -T x at T 500 ≲ 1 keV, but substantially empties and overheats the halo, generating a perennial non-cool-core group, as experienced by cosmological simulations. Even with partial evacuation, massive systems remain overheated. We show that the action of purely AGN feedback is to lower the luminosity and heat the gas, perpendicular to the fit

  18. Active Galactic Nucleus Feedback in an Elliptical Galaxy with the Most Updated AGN Physics. I. Low Angular Momentum Case

    Science.gov (United States)

    Yuan, Feng; Yoon, DooSoo; Li, Ya-Ping; Gan, Zhao-Ming; Ho, Luis C.; Guo, Fulai

    2018-04-01

    We investigate the effects of AGN feedback on the cosmological evolution of an isolated elliptical galaxy by performing two-dimensional high-resolution hydrodynamical numerical simulations. The inner boundary of the simulation is chosen so that the Bondi radius is resolved. Compared to previous works, the two accretion modes—namely, hot and cold, which correspond to different accretion rates and have different radiation and wind outputs—are carefully discriminated, and the feedback effects by radiation and wind in each mode are taken into account. The most updated AGN physics, including the descriptions of radiation and wind from the hot accretion flows and wind from cold accretion disks, are adopted. Physical processes like star formation and SNe Ia and II are taken into account. We study the AGN light curve, typical AGN lifetime, growth of the black hole mass, AGN duty cycle, star formation, and X-ray surface brightness of the galaxy. We compare our simulation results with observations and find general consistency. Comparisons with previous simulation works find significant differences, indicating the importance of AGN physics. The respective roles of radiation and wind feedback are examined, and it is found that they are different for different problems of interest, such as AGN luminosity and star formation. We find that it is hard to neglect any of them, so we suggest using the names “cold feedback mode” and “hot feedback mode” to replace the currently used ones.

  19. The XMM-Newton Wide Field Survey in the COSMOS Field: Redshift Evolution of AGN Bias and Subdominant Role of Mergers in Triggering Moderate-luminosity AGNs at Redshifts up to 2.2

    OpenAIRE

    Allevato, V.; Finoguenov, A.; Cappelluti, N.; Miyaji, T.; Hasinger, G.; Salvato, M.; Brusa, M.; Gilli, R.; Zamorani, G.; Shankar, F.; James, J. B.; McCracken, H. J.; Bongiorno, A.; Merloni, A.; Peacock, J. A.

    2011-01-01

    We present a study of the redshift evolution of the projected correlation function of 593 X-ray selected active galactic nuclei (AGNs) with I_(AB) < 23 and spectroscopic redshifts z < 4, extracted from the 0.5–2 keV X-ray mosaic of the 2.13 deg^2 XMM- Cosmic Evolution Survey (COSMOS). We introduce a method to estimate the average bias of the AGN sample and the mass of AGN hosting halos, solving the sample variance using the halo model and taking into account the growth of the structure over t...

  20. Violation of the Appelquist-Carazzone decoupling in a nonsupersymmetric grand unified theory

    International Nuclear Information System (INIS)

    Chankowski, Piotr H.; Wagner, Jakub

    2008-01-01

    We point out that in nonsupersymmetric grand unified theories, in which the SU(5) gauge symmetry is broken down to the standard model gauge group by a 24 Higgs multiplet the Appelquist-Carazzone decoupling is violated. This is because the SU(2) L Higgs triplet contained in the 24 acquires a dimension-full coupling to the SU(2) L Higgs doublets which is proportional to the grand unified symmetry breaking vacuum expectation value. As a result, at one-loop heavy gauge and Higgs fields contribution to tadpoles generates a vacuum expectation value of the triplet which is not suppressed for V→∞ and violates the custodial symmetry

  1. The LLAMA Project: A SINFONI Study of Gas Outflows and Feeding in Local, X-ray Selected AGN

    Science.gov (United States)

    Shimizu, Thomas Taro; Davies, Richard; Burtscher, Leonard; Lin, Ming-yi

    2018-01-01

    We present new results from our survey of the inner few hundred parsecs of nearby galaxies as part of our Local Luminous AGN with Matched Analogues (LLAMA) project. AGN within the LLAMA sample were selected based on detection at ultra-hard X-rays (14-195 keV) by the Swift/Burst Alert Telescope ensuring the definitive presence of an AGN. We further imposed a redshift (z 42.5) cutoff to create a complete and volume-limited sample of nearby, luminous AGN. Inactive galaxies were chosen carefully by matching in redshift, host galaxy morphology, inclination, and stellar mass to create a clean sample with which to compare to the AGN. A subset of LLAMA AGN and inactive galaxies were observed with VLT/SINFONI using adaptive optics producing high spatial resolution integral field unit spectra in the H and K band. This unique IFU data allows for analysis of a suite of NIR emission lines including [FeII], H2 (1-0) S(1), [SiVI], and Br-gamma to probe the ionized and warm molecular gas in the circumnuclear region as well as CO absorption lines to probe the stellar disk. I will present initial results from our study including the prevalence of AGN outflows along with their geometry, kinematics, and mass outflow rates and compare the mass, state, and excitation mechanisms of circumnuclear gas between AGN and inactive galaxies. Finally, I will discuss our results in the context of AGN fuelling and feedback and provide insight on interpreting similar data at higher redshift.

  2. Hosts and environments of low luminosity active galaxies in the local universe: The care and feeding of weak AGN

    Science.gov (United States)

    Parejko, John Kenneth

    The observed relationship between the mass of a galaxy's supermassive black hole and the galaxy's bulge mass suggests a relationship between the growth of the galaxy and the growth of its central black hole. When these black holes grow, they release phenomenal amounts of energy into their surroundings, possibly disrupting further growth of the galaxy. The feeding (inflowing matter) and feedback (outflowing energy) of a galaxy's central black hole may be intimately related to the properties of the host's environment, on scales many orders of magnitude beyond the black hole's gravitational influence. While feeding, a massive black hole reveals itself as an Active Galactic Nucleus (AGN), but only a few percent of all galaxies show evidence of an AGN. This thesis focuses on this question: What distinguishes galaxies that are currently hosting actively accreting black holes from those that are not? We use the vast data set provided by the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) to study the environments of a well defined sample of AGN hosts. To reduce contamination by galaxies that do not harbor actively accreting black holes, we define a clear, unambiguous sample of local AGN. Using this sample, we search for AGN in merging galaxies and measure the 2-point cross-correlation function of AGN and all galaxies to estimate the environments of AGN hosts compared to non-AGN hosts. We also describe trends in different subsamples of AGN, including luminosity and classification sub-type. Finally, we show how these techniques may be applied to future data sets such as forthcoming SDSS III data and X-ray data from the eROSITA satellite.

  3. CAUSE AND EFFECT OF FEEDBACK: MULTIPHASE GAS IN CLUSTER CORES HEATED BY AGN JETS

    International Nuclear Information System (INIS)

    Gaspari, M.; Ruszkowski, M.; Sharma, P.

    2012-01-01

    Multiwavelength data indicate that the X-ray-emitting plasma in the cores of galaxy clusters is not cooling catastrophically. To a large extent, cooling is offset by heating due to active galactic nuclei (AGNs) via jets. The cool-core clusters, with cooler/denser plasmas, show multiphase gas and signs of some cooling in their cores. These observations suggest that the cool core is locally thermally unstable while maintaining global thermal equilibrium. Using high-resolution, three-dimensional simulations we study the formation of multiphase gas in cluster cores heated by collimated bipolar AGN jets. Our key conclusion is that spatially extended multiphase filaments form only when the instantaneous ratio of the thermal instability and free-fall timescales (t TI /t ff ) falls below a critical threshold of ≈10. When this happens, dense cold gas decouples from the hot intracluster medium (ICM) phase and generates inhomogeneous and spatially extended Hα filaments. These cold gas clumps and filaments 'rain' down onto the central regions of the core, forming a cold rotating torus and in part feeding the supermassive black hole. Consequently, the self-regulated feedback enhances AGN heating and the core returns to a higher entropy level with t TI /t ff > 10. Eventually, the core reaches quasi-stable global thermal equilibrium, and cold filaments condense out of the hot ICM whenever t TI /t ff ∼< 10. This occurs despite the fact that the energy from AGN jets is supplied to the core in a highly anisotropic fashion. The effective spatial redistribution of heat is enabled in part by the turbulent motions in the wake of freely falling cold filaments. Increased AGN activity can locally reverse the cold gas flow, launching cold filamentary gas away from the cluster center. Our criterion for the condensation of spatially extended cold gas is in agreement with observations and previous idealized simulations.

  4. Infrared-faint radio sources in the SERVS deep fields. Pinpointing AGNs at high redshift

    Science.gov (United States)

    Maini, A.; Prandoni, I.; Norris, R. P.; Spitler, L. R.; Mignano, A.; Lacy, M.; Morganti, R.

    2016-12-01

    Context. Infrared-faint radio sources (IFRS) represent an unexpected class of objects which are relatively bright at radio wavelength, but unusually faint at infrared (IR) and optical wavelengths. A recent and extensive campaign on the radio-brightest IFRSs (S1.4 GHz≳ 10 mJy) has provided evidence that most of them (if not all) contain an active galactic nuclei (AGN). Still uncertain is the nature of the radio-faintest IFRSs (S1.4 GHz≲ 1 mJy). Aims: The scope of this paper is to assess the nature of the radio-faintest IFRSs, testing their classification and improving the knowledge of their IR properties by making use of the most sensitive IR survey available so far: the Spitzer Extragalactic Representative Volume Survey (SERVS). We also explore how the criteria of IFRSs can be fine-tuned to pinpoint radio-loud AGNs at very high redshift (z > 4). Methods: We analysed a number of IFRS samples identified in SERVS fields, including a new sample (21 sources) extracted from the Lockman Hole. 3.6 and 4.5 μm IR counterparts of the 64 sources located in the SERVS fields were searched for and, when detected, their IR properties were studied. Results: We compared the radio/IR properties of the IR-detected IFRSs with those expected for a number of known classes of objects. We found that IR-detected IFRSs are mostly consistent with a mixture of high-redshift (z ≳ 3) radio-loud AGNs. The faintest ones (S1.4 GHz 100 μJy), however, could be also associated with nearer (z 2) dust-enshrouded star-burst galaxies. We also argue that, while IFRSs with radio-to-IR ratios >500 can very efficiently pinpoint radio-loud AGNs at redshift 2 < z < 4, lower radio-to-IR ratios ( 100-200) are expected for higher redshift radio-loud AGNs.

  5. Dissecting the Butterfly: Dual Outflows in the Dual AGN NGC 6240

    Science.gov (United States)

    Mueller Sanchez, Francisco; Comerford, Julie; Nevin, Rebecca; Davies, Richard; Treister, Ezequiel; Privon, George

    2018-01-01

    Current theories of galaxy evolution invoke some kind of feedback (from the stars or the supermassive black hole) to explain the properties of galaxies. However, numerical simulations and observations have not been able to evaluate the real impact of feedback in galaxies. This is largely because most studies have focused on studying stellar feedback or AGN feedback alone, instead of considering the combined effect of both. In fact, this is an unexplored territory for observations due to the difficulty of separating the contribution from the two sources.In this contribution I present the discovery of a dual outflow of different species of gas in the prototypical merging galaxy NGC 6240 using HST imaging, long-slit and integral-eld spectroscopy: an AGN-driven outflow of highly-ionized gas to the northeast and a starburst-driven outflow of ionized hydrogen to the northwest. The AGN outflow extends up to 4 kpc along a position angle of 56 degrees, has a conical shape with an opening angle of 52 degrees and a maximum line-of-sight velocity of 350 km/s. The WFC3 images also reveal a bubble of Halpha emission in the northwest, which has no counterpart in [O III], consistent with a scenario in which the starburst is ionizing and driving outflowing winds which inflate the bubble at an expansion velocity of 380 km/s. Assuming a spherical geometry for the starburst-driven bubble and a conical geometry for the AGN-driven outflow, we estimate mass outflow rates of 26 Msun/yr and 62 Msun/yr, respectively. We conclude that the AGN contribution to the evolution of the merger remnant and the formation of outflowing winds is signicant in the central 5 kpc of NGC 6240.

  6. Red Geyser: A New Class of Galaxy with Large-scale AGN-driven Winds

    Science.gov (United States)

    Roy, Namrata; Bundy, Kevin; Cheung, Edmond; MaNGA Team

    2018-01-01

    A new class of quiescent (non-star-forming) galaxies harboring possible AGN-driven winds have been discovered using the spatially resolved optical spectroscopy from the ongoing SDSS-IV MaNGA (Sloan Digital Sky Survey-IV Mapping Nearby Galaxies at Apache Point Observatory) survey. These galaxies named "red geysers" constitute 5%-10% of the local quiescent galaxy population and are characterized by narrow bisymmetric ionized gas emission patterns. These enhanced patterns are seen in equivalent width maps of Hα, [OIII] and other strong emission lines. They are co-aligned with the ionized gas velocity gradients but significantly misaligned with stellar velocity gradients. They also show very high gas velocity dispersions (~200 km/s). Considering these observations in light of models of the gravitational potential, Cheung et al. argued that red geysers host large-scale AGN-driven winds of ionized gas that may play a role in suppressing star formation at late times. In this work, we test the hypothesis that AGN activity is ultimately responsible for the red geyser phenomenon. We compare the nuclear radio activity of the red geysers to a matched control sample of galaxies of similar stellar mass, redshift, rest frame NUV–r color and axis ratio. and additionally, control for the presence of ionized gas. We have used 1.4 GHz radio continuum data from the VLA FIRST Survey to stack the radio flux from the red geyser sample and control sample. We find that the red geysers have a higher average radio flux than the control galaxies at > 3σ significance. Our sample is restricted to rest-frame NUV–r color > 5, thus ruling out possible radio emission due to star formation activity. We conclude that red geysers are associated with more active AGN, supporting a feedback picture in which episodic AGN activity drives large-scale but relatively weak ionized winds in many in many early-type galaxies.

  7. Unified height systems after GOCE

    Science.gov (United States)

    Rummel, Reiner; Gruber, Thomas; Sideris, Michael; Rangelova, Elena; Woodworth, Phil; Hughes, Chris; Ihde, Johannes; Liebsch, Gunter; Rülke, Axel; Gerlach, Christian; Haagmans, Roger

    2015-04-01

    The objectives of global height unification are twofold, (1) the realization of accurate geopotential numbers C together with their standard deviation σ(C) at a selected set of stations (datum points of national height systems, geodetic fundamental stations (IERS), primary tide gauges (PSMSL) and primary reference clocks (IERS)) and (2) the determination of height off-sets between all existing regional/national height systems and one global height reference. In the future the primary method of height determination will be GPS-levelling with very stringent requirements concerning the consistency of the positioning and the gravity potential difference part. Consistency is required in terms of the applied standards (ITRF, zero tide system, geodetic reference system). Geopotential differences will be based on a next generation geopotential model combining GOCE and GRACE and a best possible collection of global terrestrial and altimetric gravity and topographic data. Ultimately, the envisaged accuracy of height unification is about 10 cm2/s2 (or 1cm). At the moment, in well surveyed regions, an accuracy of about 40 to 60 cm2/s2 (or 4 to 6cm) is attainable. Objective One can be realized by straight forward computation of geopotential numbers C, i.e. geopotential differences relative to an adopted height reference. No adjustment is required for this. Objective Two, the unification of existing height systems is achieved by employing a least-squares adjustment based on the GBVP-approach. In order to attain a non-singular solution, this requires for each included datum zone at least one geo-referenced station per zone, i.e. its ellipsoidal height h and, in addition, the corresponding physical height H (geopotential number, normal height, orthometric height, etc.). Changes in geopotential numbers of consecutive realizations reflect (1) temporal changes of station heights, (2) improvements or changes of the applied geopotential (or geoid) model and (3) improvements of the

  8. The unified coordination language UnCL.

    NARCIS (Netherlands)

    F.S. de Boer (Frank); J.V. Guillen Scholten (Juan); J.F. Jacob (Joost)

    2005-01-01

    textabstractIn this paper we show how to use a (subset) of UML as an Unified Coordination Language (UnCL) that is based on a separation of concerns between coordination and computation. As such UnCL provides a general language for the coordination of, in particular, object-oriented applications. The

  9. A Unified Introduction to Ordinary Differential Equations

    Science.gov (United States)

    Lutzer, Carl V.

    2006-01-01

    This article describes how a presentation from the point of view of differential operators can be used to (partially) unify the myriad techniques in an introductory course in ordinary differential equations by providing students with a powerful, flexible paradigm that extends into (or from) linear algebra. (Contains 1 footnote.)

  10. Unifying Learning Object Repositories in MACE

    NARCIS (Netherlands)

    Prause, Christian; Ternier, Stefaan; De Jong, Tim; Apelt, Stefan; Scholten, Marius; Wolpers, Martin; Eisenhauer, Markus; Vandeputte, Bram; Specht, Marcus; Duval, Erik

    2007-01-01

    Prause, C., Ternier, S., De Jong, T., Apelt, S., Scholten, M., Wolpers, M., et al. (2007). Unifying Learning Object Repositories in MACE. In D. Massart, J.-N. Colin & F. V. Assche (Eds.). Proceedings of the First International Workshop on Learning Object Discovery & Exchange (LODE'07). September,

  11. Unify a hazardous materials/waste program

    International Nuclear Information System (INIS)

    Carson, H.T.

    1988-01-01

    Efficiently managing a hazardous materials/waste program in a multi-facility, multi-product corporation is a major challenge. This paper describes several methods to help unify a program and gain maximum efficiency of manpower and to minimize risk

  12. Toward a Unified Theory of Human Reasoning.

    Science.gov (United States)

    Sternberg, Robert J.

    1986-01-01

    The goal of this unified theory of human reasoning is to specify what constitutes reasoning and to characterize the psychological distinction between inductive and deductive reasoning. The theory views reasoning as the controlled and mediated application of three processes (encoding, comparison and selective combination) to inferential rules. (JAZ)

  13. IDEA: A Unifying Theory for Evaluation Systems

    DEFF Research Database (Denmark)

    Bella, Giampaolo; Giustolisi, Rosario

    2017-01-01

    Secure systems for voting, exams, auctions and conference paper management are theorised to address the same problem, that of secure evaluations. In support of such a unifying theory comes a model for Secure Evaluation Systems (SES), which offers innovative common grounds to understand all four...

  14. Ultraviolet/Optical Emission of the Ionized Gas in AGN: Diagnostics of the Ionizing Source and Gas Properties

    Directory of Open Access Journals (Sweden)

    Anna Feltre

    2017-11-01

    Full Text Available Spectroscopic studies of active galactic nuclei (AGN are powerful means of probing the physical properties of the ionized gas within them. In particular, near future observational facilities, such as the James Webb Space Telescope (JWST, will allow detailed statistical studies of rest-frame ultraviolet and optical spectral features of the very distant AGN with unprecedented accuracy. In this proceedings, we discuss the various ways of exploiting new dedicated photoionization models of the narrow-line emitting regions (NLR of AGN for the interpretation of forthcoming revolutionary datasets.

  15. A Multi-wavelength Analysis of Binary-AGN Candidate PSO J334.2028+01.4075

    OpenAIRE

    Foord, Adi; Gultekin, Kayhan; Reynolds, Mark; Ayers, Megan; Liu, Tingting; Gezari, Suvi; Runnoe, Jessie

    2017-01-01

    We present analysis of the first Chandra observation of PSO J334.2028+01.4075 (PSO J334), targeted as a binary-AGN candidate based on periodic variations of the optical flux. With no prior targeted X-ray coverage for PSO J334, our new 40 ksec Chandra observation allows for the opportunity to differentiate between a single or binary-AGN system, and if a binary, can characterize the mode of accretion. Simulations show that the two expected accretion disk morphologies for binary-AGN systems are ...

  16. Ultraviolet/Optical Emission of the Ionized Gas in AGN: Diagnostics of the Ionizing Source and Gas Properties

    Energy Technology Data Exchange (ETDEWEB)

    Feltre, Anna [Univ Lyon, Univ Lyon1, Ens de Lyon, Centre National de la Recherche Scientifique, Centre de Recherche Astrophysique de Lyon UMR5574, Saint-Genis-Laval (France); Sorbonne Universités, UPMC-Centre National de la Recherche Scientifique, UMR7095, Institut d' Astrophysique de Paris, Paris (France); Charlot, Stephane [Sorbonne Universités, UPMC-Centre National de la Recherche Scientifique, UMR7095, Institut d' Astrophysique de Paris, Paris (France); Mignoli, Marco [INAF-Osservatorio Astronomico di Bologna, Bologna (Italy); Bongiorno, Angela [INAF-Osservatorio Astronomico di Roma, Monteporzio Catone (Italy); Calura, Francesco [INAF-Osservatorio Astronomico di Bologna, Bologna (Italy); Chevallard, Jacopo [Scientific Support Office, Directorate of Science and Robotic Exploration, European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Noordwijk (Netherlands); Curtis-Lake, Emma [Sorbonne Universités, UPMC-Centre National de la Recherche Scientifique, UMR7095, Institut d' Astrophysique de Paris, Paris (France); Gilli, Roberto [INAF-Osservatorio Astronomico di Bologna, Bologna (Italy); Plat, Adele, E-mail: anna.feltre@univ-lyon1.fr [Sorbonne Universités, UPMC-Centre National de la Recherche Scientifique, UMR7095, Institut d' Astrophysique de Paris, Paris (France)

    2017-11-02

    Spectroscopic studies of active galactic nuclei (AGN) are powerful means of probing the physical properties of the ionized gas within them. In particular, near future observational facilities, such as the James Webb Space Telescope (JWST), will allow detailed statistical studies of rest-frame ultraviolet and optical spectral features of the very distant AGN with unprecedented accuracy. In this proceedings, we discuss the various ways of exploiting new dedicated photoionization models of the narrow-line emitting regions (NLR) of AGN for the interpretation of forthcoming revolutionary datasets.

  17. Introduction to unified theories of weak, electromagnetic and strong interactions - SU(5)

    International Nuclear Information System (INIS)

    Billoire, Alain; Morel, Andre.

    1980-11-01

    These notes correspond to a series of lectures given at Salay during winter 1979-1980. They are meant to be an introduction to the so-called grand unified theories of weak, electromagnetic and strong interactions. In a first part, we recall in a very elementary way the standard SU(2) model of electroweak interactions, putting the emphasis on the questions which are left open by this model and which unified theories help to answer. In part II, we explain in a systematic way how unified theories can be constructed, and develop the SU(5) model in great detail. Other models, like SO(10) and E 6 , are not presented, because SU(5) is the simplest one and has been subject to the deepest investigations up to now. Also it appears that most concepts and general results are not specific to any particular symmetry group [fr

  18. Perancangan Aplikasi Informasi SMS untuk Alumni Unsoed Menggunakan UML (Unified Modeling Language

    Directory of Open Access Journals (Sweden)

    Bangun Wijayanto

    2007-02-01

    Full Text Available Unified Modeling Language (UML is a language which have come to the standard in industry to visualize, design and document the software system. Using UML we can make model for All software application type, where the application can also written in many language. SMS (Short Message Service is the best choice to solve geographic problems in spreading information to the alumni Unsoed. The aim of this research is to compile notation of UML (Unified Modeling Language in development of SMS Server for Alumni Unsoed. This research is conducted with software engineer method. The design result of software SMS alumni Unsoed present that UML (Unified Modeling Language help in design and software programming

  19. Radial and Regge excitations in unified, grand unified and subconstituent models

    International Nuclear Information System (INIS)

    Schnitzer, H.J.

    1981-01-01

    Necessary group theoretic conditions for all elementary gauge bosons and fermions of an arbitrary renormalizable gauge theory to lie on Regge trajectories are reviewed. It is then argued that in properly unified gauge theories all particles of a given spin lie on Regge trajectories. This then implies that a properly unified gauge theory has no local U(1) factor groups, and no massive fermion singlets. A consideration of the general pattern of Regge and radial recurrences to be expected in quantum field theories suggests that the presence or absence of spin 3/2 quarks and/or leptons in the TeV region will provide crucial clues to enable one to distinguish between various classes of unified, grand unified, and subconstituent models. The correct interpretation of such excited fermions will require correlation with the higgs boson mass and possible radial and Regge excitations of the weak vector bosons. (orig.)

  20. Unified treatment of the classical and quantum mechanics

    International Nuclear Information System (INIS)

    Shirokov, Yu.M.

    1979-01-01

    Classical and Quantum Mechanics are unified in the sense that almost all axioms of both mechanics are identical. The only distinction is the explicit form of one algebraic identity. The unified theory is applied to scattering problem. (Z.M.)

  1. designing a framework for a unified electronic identity system

    African Journals Online (AJOL)

    DJFLEX

    In this paper, a Unified Identity System is proposed where single electronic identity (eID) is issued that can be used ... online commerce and public sector organizations. Because ..... SearchUnifiedCommunications.com Definitions, Access date.

  2. Phenomenological aspects of unified theories

    International Nuclear Information System (INIS)

    Peccei, R.D.

    1987-01-01

    The author briefly discusses two new phenomena of recent interest, the 5/sup th/ force and variant axions. The former, for its elucidation, will require further gravitational experiments, but the author concludes that variant axions are now definitely rules out experimentally. Various aspects of superstring phenomenology are then addressed, including some of the generic predictions of superstrings and some of its generic problems. In particular, he discusses some of the phenomenological consequences of having an extra Z 0 boson and the circumstances under which this excitation is a genuine prediction of superstrings. Since it is likely that a more reliable relic of superstrings will be provided by the presence of superpartners at low energy (≤ TeV), he discusses some of the bounds for squarks and gluinos obtained at the SppS collider and the expectations for their production at the Tevatron. As a final topic, he touches upon some of the consequences that result from having the Fermi scale arise from an underlying theory. Some aspects of the composite Higgs model and of the strongly coupled standard model are briefly reviewed

  3. Unified triminimal parametrizations of quark and lepton mixing matrices

    International Nuclear Information System (INIS)

    He Xiaogang; Li Shiwen; Ma Boqiang

    2009-01-01

    We present a detailed study on triminimal parametrizations of quark and lepton mixing matrices with different basis matrices. We start with a general discussion on the triminimal expansion of the mixing matrix and on possible unified quark and lepton parametrization using quark-lepton complementarity. We then consider several interesting basis matrices and compare the triminimal parametrizations with the Wolfenstein-like parametrizations. The usual Wolfenstein parametrization for quark mixing is a triminimal expansion around the unit matrix as the basis. The corresponding quark-lepton complementarity lepton mixing matrix is a triminimal expansion around the bimaximal basis. Current neutrino oscillation data show that the lepton mixing matrix is very well represented by the tribimaximal mixing. It is natural to take it as an expanding basis. The corresponding zeroth order basis for quark mixing in this case makes the triminimal expansion converge much faster than the usual Wolfenstein parametrization. The triminimal expansion based on tribimaximal mixing can be converted to the Wolfenstein-like parametrizations discussed in the literature. We thus have a unified description between different kinds of parametrizations for quark and lepton sectors: the standard parametrizations, the Wolfenstein-like parametrizations, and the triminimal parametrizations.

  4. Implementation of a unified system for waste management

    International Nuclear Information System (INIS)

    Silva, Eliane Magalhaes Pereira da

    2006-08-01

    The process of generation and disposal of wastes has been responsible for many economical, ecological and public health problems, although the importance of its safe management for the protection of human health and the environment has long been recognized. In order to manage the hazardous wastes in an environmentally-friendly manner, many technical and administrative procedures should be implemented, from prevention and control of waste generation to a final disposal. The nuclear area personnel have a long and successful experience in all administrative and operational activities involved in the handling, treatment, conditioning, transport, storage and disposal of radioactive waste. Thus, this knowledge can be considered in the development of a unified methodology for managing all kinds of hazardous waste. The main purpose of the present work is to develop and implement a methodology, primarily to institutions that generate small amounts of waste of different compositions, on the predisposal activities management. This methodology was developed to provide a facilitator tool that should be applied by expert users. To simplify and automatize its application, a software, named SUGERE - a unified system for waste management, was developed in a Windows R environment using a Borland Delphi R package. The nuclear industry was used as a reference for developing this work and many examples of this area standards and procedures are implemented. (author)

  5. Searching for Dual AGNs in Galaxy Mergers: Understanding Double-Peaked [O III] and Ultra Hard X-rays as Selection Method

    Science.gov (United States)

    McGurk, Rosalie C.; Max, Claire E.; Medling, Anne; Shields, Gregory A.

    2015-01-01

    When galaxies merge, gas accretes onto both central supermassive black holes. Thus, one expects to see close pairs of active galactic nuclei (AGNs), or dual AGNs, in a fraction of galaxy mergers. However, finding them remains a challenge. The presence of double-peaked [O III] or of ultra hard X-rays have been proposed as techniques to select dual AGNs efficiently. We studied a sample of double-peaked narrow [O III] emitting AGNs from SDSS DR7. By obtaining new and archival high spatial resolution images taken with the Keck 2 Laser Guide Star Adaptive Optics system and the near-infrared (IR) camera NIRC2, we showed that 30% of double-peaked [O III] emission line SDSS AGNs have two spatial components within a 3' radius. However, spatially resolved spectroscopy or X-ray observations are needed to confirm these galaxy pairs as systems containing two AGNs. We followed up these spatially-double candidate dual AGNs with integral field spectroscopy from Keck OSIRIS and Gemini GMOS and with long-slit spectroscopy from Keck NIRSPEC and Shane Kast Double Spectrograph. We find double-peaked emitters are caused sometimes by dual AGN and sometimes by outflows or narrow line kinematics. We also performed Chandra X-ray ACIS-S observations on 12 double-peaked candidate dual AGNs. Using our observations and 8 archival observations, we compare the distribution of X-ray photons to our spatially double near-IR images, measure X-ray luminosities and hardness ratios, and estimate column densities. By assessing what fraction of double-peaked emission line SDSS AGNs are true dual AGNs, we can better determine whether double-peaked [O III] is an efficient dual AGN indicator and constrain the statistics of dual AGNs. A second technique to find dual AGN is the detection of ultra hard X-rays by the Swift Burst Alert Telescope. We use CARMA observations to measure and map the CO(1-0) present in nearby ultra-hard X-ray Active Galactic Nuclei (AGNs) merging with either a quiescent companion

  6. THE XMM-NEWTON WIDE FIELD SURVEY IN THE COSMOS FIELD: REDSHIFT EVOLUTION OF AGN BIAS AND SUBDOMINANT ROLE OF MERGERS IN TRIGGERING MODERATE-LUMINOSITY AGNs AT REDSHIFTS UP TO 2.2

    International Nuclear Information System (INIS)

    Allevato, V.; Hasinger, G.; Salvato, M.; Finoguenov, A.; Brusa, M.; Bongiorno, A.; Merloni, A.; Cappelluti, N.; Miyaji, T.; Gilli, R.; Zamorani, G.; Comastri, A.; Shankar, F.; James, J. B.; Peacock, J. A.; McCracken, H. J.; Silverman, J.

    2011-01-01

    We present a study of the redshift evolution of the projected correlation function of 593 X-ray selected active galactic nuclei (AGNs) with I AB 2 XMM- Cosmic Evolution Survey (COSMOS). We introduce a method to estimate the average bias of the AGN sample and the mass of AGN hosting halos, solving the sample variance using the halo model and taking into account the growth of the structure over time. We find evidence of a redshift evolution of the bias factor for the total population of XMM-COSMOS AGNs from b-bar ( z-bar =0.92)=2.30±0.11 to b-bar ( z-bar =1.94)=4.37±0.27 with an average mass of the hosting dark matter (DM) halos log M 0 (h -1 M sun ) ∼ 13.12 ± 0.12 that remains constant at all z 0 (h -1 M sun ) ∼ 13.28 ± 0.07 and log M 0 (h -1 M sun ) ∼ 13.00 ± 0.06 for BL/X-ray unobscured AGNs and NL/X-ray obscured AGNs, respectively. The theoretical models, which assume a quasar phase triggered by major mergers, cannot reproduce the high bias factors and DM halo masses found for X-ray selected BL AGNs with L BOL ∼ 2 x 10 45 erg s -1 . Our work extends up to z ∼ 2.2 the z ∼< 1 statement that, for moderate-luminosity X-ray selected BL AGNs, the contribution from major mergers is outnumbered by other processes, possibly secular ones such as tidal disruptions or disk instabilities.

  7. CHANDRA X-RAY AND HUBBLE SPACE TELESCOPE IMAGING OF OPTICALLY SELECTED KILOPARSEC-SCALE BINARY ACTIVE GALACTIC NUCLEI. II. HOST GALAXY MORPHOLOGY AND AGN ACTIVITY

    International Nuclear Information System (INIS)

    Shangguan, Jinyi; Ho, Luis C.; Liu, Xin; Shen, Yue; Peng, Chien Y.; Greene, Jenny E.; Strauss, Michael A.

    2016-01-01

    Binary active galactic nuclei (AGNs) provide clues to how gas-rich mergers trigger and fuel AGNs and how supermassive black hole (SMBH) pairs evolve in a gas-rich environment. While significant effort has been invested in their identification, the detailed properties of binary AGNs and their host galaxies are still poorly constrained. In a companion paper, we examined the nature of ionizing sources in the double nuclei of four kiloparsec-scale binary AGNs with redshifts between 0.1 and 0.2. Here, we present their host galaxy morphology based on F336W ( U -band) and F105W ( Y -band) images taken by the Wide Field Camera 3 on board the Hubble Space Telescope . Our targets have double-peaked narrow emission lines and were confirmed to host binary AGNs with follow-up observations. We find that kiloparsec-scale binary AGNs occur in galaxy mergers with diverse morphological types. There are three major mergers with intermediate morphologies and a minor merger with a dominant disk component. We estimate the masses of the SMBHs from their host bulge stellar masses and obtain Eddington ratios for each AGN. Compared with a representative control sample drawn at the same redshift and stellar mass, the AGN luminosities and Eddington ratios of our binary AGNs are similar to those of single AGNs. The U − Y color maps indicate that clumpy star-forming regions could significantly affect the X-ray detection of binary AGNs, e.g., the hardness ratio. Considering the weak X-ray emission in AGNs triggered in merger systems, we suggest that samples of X-ray-selected AGNs may be biased against gas-rich mergers.

  8. Ultra-Fast Outflows in Radio-Loud AGN: New Constraints on Jet-Disk Connection

    Science.gov (United States)

    Sambruna, Rita

    There is strong observational and theoretical evidence that outflows/jets are coupled to accretion disks in black hole accreting systems, from Galactic to extragalactic sizes. While in radio-quiet AGN there is ample evidence for the presence of Ultra-Fast Outflows (UFOs) from the presence of blue-shifted absorption features in their 4-10~keV spectra, sub-relativistic winds are expected on theoretical basis in radio-loud AGN but have not been observed until now. Our recent Suzaku observations of 5 bright Broad- Line Radio Galaxies (BLRGs, the radio-loud counterparts of Seyferts) has started to change this picture. We found strong evidence for UFOs in 3 out of 5 BLRGs, with ionization parameters, column densities, and velocities of the absorber similar to Seyferts. Moreover, the outflows in BLRGs are likely to be energetically very significant: from the Suzaku data of the three sources, outflow masses similar to the accretion masses and kinetic energies of the wind similar to the X-ray luminosity and radio power of the jet are inferred. Clearly, UFOs in radio-loud AGN represent a new key ingredient to understand their central engines and in particular, the jet-disk linkage. Our discovery of UFOs in a handful of BLRGs raises the questions of how common disk winds are in radio-loud AGN, what the absorber physical and dynamical characteristics are, and what is the outflow role in broader picture of galaxy-black hole connection for radio sources, i.e., for large-scale feedback models. To address these and other issues, we propose to use archival XMM-Newton and Suzaku spectra to search for Ultra-Fast Outflows in a large number of radio sources. Over a period of two years, we will conduct a systematic, uniform analysis of the archival X-ray data, building on our extensive experience with a similar previous project for Seyferts, and using robust analysis and statistical methodologies. As an important side product, we will also obtain accurate, self- consistent measurements

  9. Multi-planed unified switching topologies

    Science.gov (United States)

    Chen, Dong; Heidelberger, Philip; Sugawara, Yutaka

    2017-07-04

    An apparatus and method for extending the scalability and improving the partitionability of networks that contain all-to-all links for transporting packet traffic from a source endpoint to a destination endpoint with low per-endpoint (per-server) cost and a small number of hops. An all-to-all wiring in the baseline topology is decomposed into smaller all-to-all components in which each smaller all-to-all connection is replaced with star topology by using global switches. Stacking multiple copies of the star topology baseline network creates a multi-planed switching topology for transporting packet traffic. Point-to-point unified stacking method using global switch wiring methods connects multiple planes of a baseline topology by using the global switches to create a large network size with a low number of hops, i.e., low network latency. Grouped unified stacking method increases the scalability (network size) of a stacked topology.

  10. Finite Unified Theories and the Higgs boson

    CERN Document Server

    Heinemeyer, Sven; Zoupanos, George

    2012-01-01

    All-loop Finite Unified Theories (FUTs) are very interesting N = 1 supersymmetric Grand Unified Theories (GUTs) realising an old field theory dream, and moreover have a remarkable predictive power due to the required reduction of couplings. Based on this theoretical framework phenomenologically consistent FUTs have been constructed. Here we review two FUT models based on the SU(5) gauge group, which can be seen as special, restricted and thus very predictive versions of the MSSM. We show that from the requirement of correct prediction of quark masses and other experimental constraints a light Higgs-boson mass in the range M_h ~ 121 - 126 GeV is predicted, in striking agreement with recent experimental results from ATLAS and CMS. The model furthermore naturally predicts a relatively heavy spectrum with colored supersymmetric particles above ~ 1.5 TeV in agreement with the non-observation of those particles at the LHC.

  11. Unified-field theory: yesterday, today, tomorrow

    International Nuclear Information System (INIS)

    Bergman, P.G.

    1982-01-01

    Beginning with the expounding of Einstein understanding of advantages and disadvantages of general relativity theory, the authors proceed to consideration of what the complete unified theory have to be according to Einstein. The four theories which can be considered as ''unified'', namely weyl and Calutsa ones, worked out a half of century ago, and twistor twisting and supersymmetry theories, nowadays attracting attention, are briefly described and discussed. The authors come to a conclusion that achievements in elementary-particle physics have to affect any future theory, that this theory has to explain the principle contradictions between classical and quantum field theories, and that finally it can lead to change of the modern space-time model as a four-dimensional variety

  12. Towards a Unified Global ICT Infrastructure

    DEFF Research Database (Denmark)

    Madsen, Ole Brun

    2006-01-01

    A successful evolution towards a unified global WAN platform allowing for the coexistence and interoperability of all kind of services requires careful planning of the next generation global cooperative wired and wireless information infrastructure. The absence of commonly agreed upon and adopted...... to be solved can be found in the interrelation between communication, connectivity and convergence. This paper will focus on steps to be taken in planning the physical infrastructure as a prerequisite for a successful evolution....

  13. Unified geometric description of black hole thermodynamics

    International Nuclear Information System (INIS)

    Alvarez, Jose L.; Quevedo, Hernando; Sanchez, Alberto

    2008-01-01

    In the space of thermodynamic equilibrium states we introduce a Legendre invariant metric which contains all the information about the thermodynamics of black holes. The curvature of this thermodynamic metric becomes singular at those points where, according to the analysis of the heat capacities, phase transitions occur. This result is valid for the Kerr-Newman black hole and all its special cases and, therefore, provides a unified description of black hole phase transitions in terms of curvature singularities.

  14. The group manifold approach to unified gravity

    International Nuclear Information System (INIS)

    Regge, T.

    1984-01-01

    These lectures start with a synopsis of historical results in the construction of unified theories of gravity. The author keeps some mathematical rigour throughout the lectures. He gives a provisional description of supermanifolds and a set of formal rules intended to manipulate superforms or supermanifolds. Super Lie groups are discussed as well as the dimensional reduction of gravity theories, the Kaluza-Klein theory. A formal introduction of supersymmetry is given. (Auth.)

  15. Unifying Ancient and Modern Geometries Through Octonions

    International Nuclear Information System (INIS)

    Catto, Sultan; Gürcan, Yasemin; Kurt, Levent; Khalfan, Amish

    2016-01-01

    We show the first unified description of some of the oldest known geometries such as the Pappus’ theorem with more modern ones like Desargues' theorem, Monge's theorem and Ceva's theorem, through octonions, the highest normed division algebra in eight dimensions. We also show important applications in hadronic physics, giving a full description of the algebra of color applicable to quark physics, and comment on further applications. (paper)

  16. A unified architecture of transcriptional regulatory elements

    DEFF Research Database (Denmark)

    Andersson, Robin; Sandelin, Albin Gustav; Danko, Charles G.

    2015-01-01

    Gene expression is precisely controlled in time and space through the integration of signals that act at gene promoters and gene-distal enhancers. Classically, promoters and enhancers are considered separate classes of regulatory elements, often distinguished by histone modifications. However...... and enhancers are considered a single class of functional element, with a unified architecture for transcription initiation. The context of interacting regulatory elements and the surrounding sequences determine local transcriptional output as well as the enhancer and promoter activities of individual elements....

  17. Neutrino mixing in a grand unified theory

    International Nuclear Information System (INIS)

    Milton, K.; Tanaka, K.

    1980-01-01

    Neutrino mixing in a grand unified theory in which the neutrino mass matrix is determined by the Gell-Mann-Ramond-Slansky mechanism was investigated. With an arbitrary real right-handed Majorana mass matrix which incorporates three neutrino mass scales, the effects of the up-quark mass matrix are found to be dominant and as a result no significant mixing of ν/sub e/ occurs, while ν/sub μ/ - ν/sub γ/ mixing can be substantial

  18. Towards a unified theory of reciprocity.

    Science.gov (United States)

    Rosas, Alejandro

    2012-02-01

    In a unified theory of human reciprocity, the strong and weak forms are similar because neither is biologically altruistic and both require normative motivation to support cooperation. However, strong reciprocity is necessary to support cooperation in public goods games. It involves inflicting costs on defectors; and though the costs for punishers are recouped, recouping costs requires complex institutions that would not have emerged if weak reciprocity had been enough.

  19. A Unified Framework for Systematic Model Improvement

    DEFF Research Database (Denmark)

    Kristensen, Niels Rode; Madsen, Henrik; Jørgensen, Sten Bay

    2003-01-01

    A unified framework for improving the quality of continuous time models of dynamic systems based on experimental data is presented. The framework is based on an interplay between stochastic differential equation (SDE) modelling, statistical tests and multivariate nonparametric regression. This co......-batch bioreactor, where it is illustrated how an incorrectly modelled biomass growth rate can be pinpointed and an estimate provided of the functional relation needed to properly describe it....

  20. Empirical links between XRB and AGN accretion using the complete z < 0.4 spectroscopic CSC/SDSS catalog

    Energy Technology Data Exchange (ETDEWEB)

    Trichas, Markos [EADS Astrium, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2AS (United Kingdom); Green, Paul J.; Aldcroft, Tom; Sobolewska, Malgosia; Kim, Dong-Woo [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Constantin, Anca [Department of Physics and Astronomy, James Madison University, PHCH, Harrisonburg, VA 22807 (United States); Kalfountzou, Eleni [Center for Astrophysics, Science and Technology Research Institute, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom); Hyde, Ashley K. [Astrophysics Group, Imperial College London, London SW7 2AZ (United Kingdom); Zhou, Hongyan [Center for Astrophysics, University of Science and Technology of China, Hefei 230026 (China); Haggard, Daryl [Center for Interdisciplinary Exploration and Research in Astrophysics, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Kelly, Brandon C., E-mail: markos.trichas@astrium.eads.net [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93107 (United States)

    2013-12-01

    Striking similarities have been seen between accretion signatures of Galactic X-ray binary (XRB) systems and active galactic nuclei (AGNs). XRB spectral states show a V-shaped correlation between X-ray spectral hardness and Eddington ratio as they vary, and some AGN samples reveal a similar trend, implying analogous processes at vastly larger masses and timescales. To further investigate the analogies, we have matched 617 sources from the Chandra Source Catalog to Sloan Digital Sky Survey spectroscopy, and uniformly measured both X-ray and optical spectral characteristics across a broad range of AGN and galaxy types. We provide useful tabulations of X-ray spectral slope for broad- and narrow-line AGNs, star-forming and passive galaxies, and composite systems, also updating relationships between optical (Hα and [O III]) line emission and X-ray luminosity. We further fit broadband spectral energy distributions with a variety of templates to estimate bolometric luminosity. Our results confirm a significant trend in AGNs between X-ray spectral hardness and Eddington ratio expressed in X-ray luminosity, albeit with significant dispersion. The trend is not significant when expressed in the full bolometric or template-estimated AGN luminosity. We also confirm a relationship between the X-ray/optical spectral slope α{sub ox} and Eddington ratio, but it may not follow the trend predicted by analogy with XRB accretion states.

  1. Cosmic strings in unified gauge theories

    International Nuclear Information System (INIS)

    Everett, A.E.

    1981-01-01

    Some spontaneously broken gauge theories can give rise to stringlike vacuum structures (vortices). It has been pointed out by Vilenkin that in grand unified theories these can be sufficiently massive to have cosmological implications, e.g., in explaining the formation of galaxies. The circumstances in which such structures occur are examined. They do not occur in the simplest grand unified theories, but can occur in some more elaborate models which have been proposed. The cross section for the scattering of elementary particles by strings is estimated. This is used to evaluate the effect of collisions on the dynamics of a collapsing circular string, with particular attention to the question of whether energy dissipation by collision can reduce the rate of formation of black holes by collapsed strings, which may be unacceptably large in models where strings occur. It is found that the effect of collisions is not important in the case of grand unified strings, although it can be important for lighter strings

  2. Coset realization of unifying W-algebras

    International Nuclear Information System (INIS)

    Blumenhagen, R.; Huebel, R.

    1994-06-01

    We construct several quantum coset W-algebras, e.g. sl(2,R)/U(1) and sl(2,R)+sl(2,R)/sl(2,R), and argue that they are finitely nonfreely generated. Furthermore, we discuss in detail their role as unifying W-algebras of Casimir W-algebras. We show that it is possible to give coset realizations of various types of unifying W-algebras, e.g. the diagonal cosets based on the symplectic Lie algebras sp(2n) realize the unifying W-algebras which have previously been introduced as 'WD -n '. In addition, minimal models of WD -n are studied. The coset realizations provide a generalization of level-rank-duality of dual coset pairs. As further examples of finitely nonfreely generated quantum W-algebras we discuss orbifolding of W-algebras which on the quantum level has different properties than in the classical case. We demonstrate in some examples that the classical limit according to Bowcock and Watts of these nonfreely finitely generated quantum W-algebras probably yields infinitely nonfreely generated classical W-algebras. (orig.)

  3. Unified strength theory and its applications

    CERN Document Server

    Yu, Mao-Hong

    2004-01-01

    This is a completely new theory dealing with the yield and failure of materials under multi-axial stresses. It provides a system of yield and failure criteria adopted for most materials, from metallic materials to rocks, concretes, soils, polymers etc. The Unified Strength Theory has been applied successfully to analyse the elastic limit, plastic limit capacities, the dynamic response behavior for some structures under static and moderate impulsive load, and may be implemented in some elasto-plastic finite element computer codes. The Unified Strength Theory is described in detail and by using this theory a series of results can be obtained. The Unified Strength Theory can improve the conservative Mohr-Coulomb Theory, and since intermediate principal stress is not taken into account in the Mohr-Coulomb theory and most experimental data is not pertainable to the Mohr-Coulomb Theory, a considerable economic benefit may be obtained. The book can also increase the effect of most commercial finite element computer ...

  4. Proton decay in grand unified theories

    International Nuclear Information System (INIS)

    Lucha, W.

    1984-01-01

    Interactions which violate the conservation of baryon and lepton number represent an intrinsic part of all grand unified theories (GUTs) of strong and electroweak interactions. These new interactions - predicted within the framework of GUTs - generate B and L violating four-fermion interactions via the exchange of superheavy particles which cannot be ascribed a well-defined baryon or lepton number. The effective coupling constant of these four-fermion interactions might be large enough to make the proton decay detectable by the present generation of experiments. In this review the basic concepts of conventional as well as supersymmetric GUTs relevant for proton decay are sketched. The baryon number violating sector of grand unified theories is discussed in more detail. Special emphasis is laid on the various selection rules arising as consequences of low-energy gauge invariance and supersymmetry for proton decay. These selection rules already determine the coarse pattern of the resulting decay modes and branching ratios without any reference to or detailed knowledge of the underlying grand unified theory. Finally the numerous theoretical predictions are summarized and confronted with experiment. (Author)

  5. Some consequences of embedding heavy color in grand unified theories

    International Nuclear Information System (INIS)

    Elias, V.

    1980-01-01

    I show that ''standard'' embedding constraints cannot accommodate an empirically motivated value for the heavy-color (HC) momentum scale Λ/sub HC/ if the heavy-color group is SU(N>3). The heavy-color group can be SU(3), provided such constraints are relaxed in order to allow fermions to contribute differentially to SU(3)/sub HC/ and SU(3)/sub QCD/ β-functions (QCD=quantum chromodynamics). Theories successfully embedding G/sub HC/>SU(3) along with the known interactions are shown to require vastly reduced unification mass scales. As an example, empirically acceptable values for Λ/sub HC/, sin 2 theta/sub W/, and α/sub s/(m/sub W/) as well as a unification mass scale within an order of magnitude of Λ/sub HC/ are accommodated within very large models based on [SU(2n)] 4 unifying symmetry

  6. Squark and slepton mass relations in grand unified theories

    International Nuclear Information System (INIS)

    Cheng, H.; Hall, L.J.

    1995-01-01

    In the minimal supersymmetric standard model, assuming universal scalar masses at large energies, there are four intragenerational relations between the masses of the squarks and sleptons for each light generation. In this paper we study the scalar mass relations which follow only from the assumption that at large energies there is a grand unified theory which leads to a significant prediction of the weak mixing angle. Two new intragenerational mass relations for each of the light generations are derived. In addition, a third mass relation is found which relates the Higgs boson masses, the masses of the third generation scalars, and the masses of the scalars of the lighter generations. Verification of a fourth mass relation, involving only the charged slepton masses, provides a signal for SO(10) unification

  7. Unifying logarithmic and factorial behavior in high-energy scattering

    International Nuclear Information System (INIS)

    Cornwall, J.M.; Morris, D.A.

    1995-01-01

    The elegant instanton calculus of Lipatov and others used to find factorially divergent behavior (g N N exclamation point) for N g much-gt 1 in gφ 4 perturbation theory is strictly only applicable when all external momenta vanish; a description of high-energy 2→N scattering with N massive particles is beyond the scope of such techniques. On the other hand, a standard multiperipheral treatment of scattering with its emphasis on leading logarithms gives a reasonable picture of high-energy behavior but does not result in factorial divergences. Using a straightforward graphical analysis we present a unified picture of both these phenomena as they occur in the two-particle total cross section of gφ 4 theory. We do not attempt to tame the unitarity violations associated with either multiperipheralism or the Lipatov technique at strong coupling

  8. Agnes high, Western Desert, Egypt: A structural study in view of potential data modelling

    Directory of Open Access Journals (Sweden)

    A.A. Azab

    2014-06-01

    Results of the qualitative analysis show that Agnes high gravity and magnetic association is mainly caused by a near surface igneous intrusion of NW orientation. Quantitatively, regional models indicate a normal continental type of crust, which is divided into upper and lower by the Conrad surface (21.5–22 km. The crust–mantle interface lies at 32–33 km meanwhile the magnetic crust reaches a depth of 16 km. Local models reveal that the basement rocks north and south of the Agnes high were offset by some 6–8 km and 3–4.5 km, respectively. Statistically, the area was controlled by two main old trends; the most prevailing WNW to NNW (East African and the less abundant ENE (Syrian Arc trends. These two principal trends almost have its doubtless impact on preservation of possible accumulations.

  9. Variability: A X-ray ruler for the AGN structure model

    Directory of Open Access Journals (Sweden)

    Guainazzi M.

    2012-12-01

    Full Text Available Validating our understanding of the innermost structure of Active Galactic Nuclei (AGN would require resolving sub-parsec scales. Lacking adequate direct imaging, X-ray astronomy can still contribute to this undertaking through the study of spectral variability on time-scales from days to years. This bears information on the location of gaseous and dusty systems in the innermost regions around the accreting supermassive black hole. In this paper I discuss the application of this concept in two specific contexts: a “fast” column density variations in heavily obscured AGN; b reverberation of optically-thick reprocessing. These results lend support to a scenario where obscuration and optically thick reprocessing are due to a variety of different systems, ranging from the Broad Line Regions to a clumpy structure extended on larger scales up to hundreds of parsecs.

  10. Constraints on Particles and Fields from Full Stokes Observations of AGN

    Directory of Open Access Journals (Sweden)

    Daniel C. Homan

    2018-01-01

    Full Text Available Combined polarization imaging of radio jets from Active Galactic Nuclei (AGN in circular and linear polarization, also known as full Stokes imaging, has the potential to constrain both the magnetic field structure and particle properties of jets. Although only a small fraction of the emission when detected, typically less than a few tenths of a percent but up to as much as a couple of percent in the strongest resolved sources, circular polarization directly probes the magnetic field and particles within the jet itself and is not expected to be modified by external screens. A key to using full Stokes observations to constrain jet properties is obtaining a better understanding of the emission of circular polarization, including its variability and spectrum. We discuss what we have learned so far from parsec scale monitoring observations in the MOJAVE program and from multi-frequency observations of selected AGN.

  11. Reliability and validity of the Wolfram Unified Rating Scale (WURS

    Directory of Open Access Journals (Sweden)

    Nguyen Chau

    2012-11-01

    Full Text Available Abstract Background Wolfram syndrome (WFS is a rare, neurodegenerative disease that typically presents with childhood onset insulin dependent diabetes mellitus, followed by optic atrophy, diabetes insipidus, deafness, and neurological and psychiatric dysfunction. There is no cure for the disease, but recent advances in research have improved understanding of the disease course. Measuring disease severity and progression with reliable and validated tools is a prerequisite for clinical trials of any new intervention for neurodegenerative conditions. To this end, we developed the Wolfram Unified Rating Scale (WURS to measure the severity and individual variability of WFS symptoms. The aim of this study is to develop and test the reliability and validity of the Wolfram Unified Rating Scale (WURS. Methods A rating scale of disease severity in WFS was developed by modifying a standardized assessment for another neurodegenerative condition (Batten disease. WFS experts scored the representativeness of WURS items for the disease. The WURS was administered to 13 individuals with WFS (6-25 years of age. Motor, balance, mood and quality of life were also evaluated with standard instruments. Inter-rater reliability, internal consistency reliability, concurrent, predictive and content validity of the WURS were calculated. Results The WURS had high inter-rater reliability (ICCs>.93, moderate to high internal consistency reliability (Cronbach’s α = 0.78-0.91 and demonstrated good concurrent and predictive validity. There were significant correlations between the WURS Physical Assessment and motor and balance tests (rs>.67, ps>.76, ps=-.86, p=.001. The WURS demonstrated acceptable content validity (Scale-Content Validity Index=0.83. Conclusions These preliminary findings demonstrate that the WURS has acceptable reliability and validity and captures individual differences in disease severity in children and young adults with WFS.

  12. Spectral energy distribution variations of nearby Seyfert galaxies during AGN watch monitoring programs

    Science.gov (United States)

    Kilerci Eser, Ece; Vestergaard, M.

    2018-02-01

    We present and analyse quasi-simultaneous multi-epoch spectral energy distributions (SEDs) of seven reverberation-mapped active galactic nuclei (AGNs) for which accurate black hole mass measurements and suitable archival data are available from the `AGN Watch' monitoring programs. We explore the potential of optical-UV and X-ray data, obtained within 2 d, to provide more accurate SED-based measurements of individual AGN and quantify the impact of source variability on key measurements typically used to characterize the black hole accretion process plus on bolometric correction factors at 5100 Å, 1350 Å and for the 2-10 keV X-ray band, respectively. The largest SED changes occur on long time-scales (≳1 year). For our small sample, the 1μm to 10 keV integrated accretion luminosity typically changes by 10 per cent on short time-scales (over 20 d), by ˜30 per cent over a year, but can change by 100 per cent or more for individual AGN. The extreme ultraviolet (EUV) gap is the most uncertain part of the intrinsic SED, introducing a ˜25 per cent uncertainty in the accretion-induced luminosity, relative to the model independent interpolation method that we adopt. That aside, our analysis shows that the uncertainty in the accretion-induced luminosity, the Eddington luminosity ratio and the bolometric correction factors can be reduced (by a factor of two or more) by use of the SEDs built from data obtained within 20 d. However, \\dot{M} and η are mostly limited by the unknown EUV emission and the unknown details of the central engine and our aspect angle.

  13. Observational Corollaries of Proto-AGN: Understanding Formation of Supermassive Black Hole Seeds

    Science.gov (United States)

    Shlosman, Isaac

    2016-10-01

    Formation of supermassive black holes (SMBHs) is still an enigma. Recent detections of high-z quasars which harbor massive SMBHs provide a challenge to models of structure buildup in the universe. Main alternatives for the formation of SMBH seeds are (1) remnants of Population III stars, and (2) a direct baryonic collapse within dark matter (DM) halos of 10^8 Mo -- first halos whose virial temperature exceeds 10^4 K, and which can lead to the formation of proto-AGN -- luminous pre-SMBH objects. Potentially, this can involve both high-z objects as well as low-z dwarf galaxies in voids. We focus on the direct collapse in 10^8 Mo halos which circumvents the pitfalls of Pop III remnants. The collapse can proceed via a radiation pressure-supported quasistar -- with a modified blackbody continuum. Such a configuration requires a very efficient angular momentum transfer. Or, it can form a thick, differentially rotating, self-gravitating disk, which is associated with an X-ray-infrared continuum and Seyfert-level luminosity, anisotropic emission, massive bi-conical outflows, and will be a powerful source of the Ly-alpha emission. We propose to perform radiative transfer in the continuum and hydrogen lines (e.g., Lyman and Balmer), using our models of proto-AGN, and do it on-the-fly -- concurrently with the collapse. We shall test the path to quasistellar and disky proto-AGN, produce first synthetic spectra of proto-AGN, and address the issue of feasibility of their detection by the JWST. Finally, we shall develop the strategy of searching for these objects at high- and low-z, based on the specific features in the spectra and associated variability.

  14. Cause and Effect of Feedback: Multiphase Gas in Cluster Cores Heated by AGN Jets

    Science.gov (United States)

    Gaspari, M.; Ruszkowski, M.; Sharma, P.

    2012-02-01

    Multiwavelength data indicate that the X-ray-emitting plasma in the cores of galaxy clusters is not cooling catastrophically. To a large extent, cooling is offset by heating due to active galactic nuclei (AGNs) via jets. The cool-core clusters, with cooler/denser plasmas, show multiphase gas and signs of some cooling in their cores. These observations suggest that the cool core is locally thermally unstable while maintaining global thermal equilibrium. Using high-resolution, three-dimensional simulations we study the formation of multiphase gas in cluster cores heated by collimated bipolar AGN jets. Our key conclusion is that spatially extended multiphase filaments form only when the instantaneous ratio of the thermal instability and free-fall timescales (t TI/t ff) falls below a critical threshold of ≈10. When this happens, dense cold gas decouples from the hot intracluster medium (ICM) phase and generates inhomogeneous and spatially extended Hα filaments. These cold gas clumps and filaments "rain" down onto the central regions of the core, forming a cold rotating torus and in part feeding the supermassive black hole. Consequently, the self-regulated feedback enhances AGN heating and the core returns to a higher entropy level with t TI/t ff > 10. Eventually, the core reaches quasi-stable global thermal equilibrium, and cold filaments condense out of the hot ICM whenever t TI/t ff fashion. The effective spatial redistribution of heat is enabled in part by the turbulent motions in the wake of freely falling cold filaments. Increased AGN activity can locally reverse the cold gas flow, launching cold filamentary gas away from the cluster center. Our criterion for the condensation of spatially extended cold gas is in agreement with observations and previous idealized simulations.

  15. A human reliability analysis of the University of New Mexico's AGN- 201M nuclear research reactor

    International Nuclear Information System (INIS)

    Brumburgh, G.P.; Heger, A.S.

    1992-01-01

    During 1990--1991, a probabilistic risk assessment was conducted on the University of New Mexico's AGN-201M nuclear research reactor to address the risk and consequence of a maximum hypothetical release accident. The assessment indicated a potential for consequential human error to precipitate Chis scenario. Subsequently, a human reliability analysis was performed to evaluate the significance of human interaction on the reactor's safety systems. This paper presents the results of that investigation

  16. The Origin and Structure of the Magnetic Fields and Currents of AGN Jets

    Directory of Open Access Journals (Sweden)

    Denise Gabuzda

    2017-02-01

    Full Text Available This paper reviews observational evidence obtained to date about the overall structure of the magnetic fields in the jets of Active Galactic Nuclei (AGN. Because they are sensitive to the line-of-sight magnetic-field component, Faraday rotation observations of AGN jets provide an effective tool for searching for toroidal jet magnetic fields, whose line-of-sight component changes systematically across the jet. Transverse Faraday rotation measure (RM gradients providing direct evidence for helical/toroidal magnetic fields have been reliably detected in nearly 40 AGN on parsec scales. Helical magnetic fields are believed to form due to the combined action of the rotation of the central black hole and accretion disk, and these observations demonstrate that at least some of this helical field survives to distances well beyond the Very Long Baseline Interferometry (VLBI core. Observations of reversals in the direction of the transverse RM gradients in a number of AGN provide evidence for a“return”magnetic field forming a nested helical-field structure with oppositely directed azimuthal components in the inner and outer regions of the helical magnetic field. The collected data now provide firm evidence for a predominance of inward jet currents on parsec scales and outward currents on scales greater than a few tens of parsecs. This suggests a global pattern of magnetic fields and currents with an inward current near the jet axis and an outward current farther from the jet axis, with these currents closing in the accretion disk and far out in the radio lobes, forming a self-consistent set of fields and currents together with the implied nested helical-field structure.

  17. Statistical analysis of COMPTEL maximum likelihood-ratio distributions: evidence for a signal from previously undetected AGN

    International Nuclear Information System (INIS)

    Williams, O. R.; Bennett, K.; Much, R.; Schoenfelder, V.; Blom, J. J.; Ryan, J.

    1997-01-01

    The maximum likelihood-ratio method is frequently used in COMPTEL analysis to determine the significance of a point source at a given location. In this paper we do not consider whether the likelihood-ratio at a particular location indicates a detection, but rather whether distributions of likelihood-ratios derived from many locations depart from that expected for source free data. We have constructed distributions of likelihood-ratios by reading values from standard COMPTEL maximum-likelihood ratio maps at positions corresponding to the locations of different categories of AGN. Distributions derived from the locations of Seyfert galaxies are indistinguishable, according to a Kolmogorov-Smirnov test, from those obtained from ''random'' locations, but differ slightly from those obtained from the locations of flat spectrum radio loud quasars, OVVs, and BL Lac objects. This difference is not due to known COMPTEL sources, since regions near these sources are excluded from the analysis. We suggest that it might arise from a number of sources with fluxes below the COMPTEL detection threshold

  18. The evolution of and starburst-agn connection in luminous and ultraluminous infrared galaxies and their link to globular cluster formation

    Science.gov (United States)

    Fiorenza, Stephanie Lynn

    The evolutionary connection between nuclear starbursts and active galactic nuclei (AGN) in luminous infrared galaxies (LIRGs; 1011 diagrams. I show that for the U/LIRGs in my sample the properties that describe their nuclear starbursts and AGN (e.g. star formation rate (SFR), L[O III], optical D parameter, D4000, and EW(Hdelta)) are independent of one another, ensuring that no biases affect correlations between these properties and objects' locations on the BPT diagrams. I then derive evolutionary paths on the BPT diagram involving [N II]/Halpha that are based on how these properties vary between two U/LIRGs positioned at the end-points. The paths involve U/LIRGs that decrease in SFR and increase in AGN activity. Paths with U/LIRGs that evolve into high luminosity AGN likely do so due to recent, strong starbursts. Second, to study how the properties of the IR power sources in U/LIRGs vary, I use a combination of photometric data points that I carefully measure (using photometry from SDSS, 2MASS, WISE, and Spitzer) and that I retrieve from catalogues (IRAS, AKARI, and ISO) to perform UV to FIR SED-fitting with CIGALE (Code Investigating GALaxy Emission) for 34 U/LIRGs from the IRAS 2 Jy Redshift Survey with 0.01 statistical analysis, and fit an exponential curve to the data to describe the expected amount of decrease in SFR seen for a U/LIRG in my sample over a given change in starburst age. Finally, I find evidence that the stellar mass and starburst mass fractions influence whether a U/LIRG in my sample will have a strong AGN and SFR, respectively. I compare the SFR-Mstar relationship seen in my sample with those predicted by models and found from previous observations. I find that the U/LIRGs with older starbursts (>125 Myr) agree with previous results, while those with younger starbursts show a large dispersion in Mstar. I conclude that this is supporting evidence that the star formation histories and timescales at which the IR power sources in U/LIRGs evolve

  19. The Effect of Ag and Ag+N Ion Implantation on Cell Attachment Properties

    International Nuclear Information System (INIS)

    Urkac, Emel Sokullu; Oztarhan, Ahmet; Gurhan, Ismet Deliloglu; Iz, Sultan Gulce; Tihminlioglu, Funda; Oks, Efim; Nikolaev, Alexey; Ila, Daryush

    2009-01-01

    Implanted biomedical prosthetic devices are intended to perform safely, reliably and effectively in the human body thus the materials used for orthopedic devices should have good biocompatibility. Ultra High Molecular Weight Poly Ethylene (UHMWPE) has been commonly used for total hip joint replacement because of its very good properties. In this work, UHMWPE samples were Ag and Ag+N ion implanted by using the Metal-Vapor Vacuum Arc (MEVVA) ion implantation technique. Samples were implanted with a fluency of 1017 ion/cm2 and extraction voltage of 30 kV. Rutherford Backscattering Spectrometry (RBS) was used for surface studies. RBS showed the presence of Ag and N on the surface. Cell attachment properties investigated with model cell lines (L929 mouse fibroblasts) to demonstrate that the effect of Ag and Ag+N ion implantation can favorably influence the surface of UHMWPE for biomedical applications. Scanning electron microscopy (SEM) was used to demonstrate the cell attachment on the surface. Study has shown that Ag+N ion implantation represents more effective cell attachment properties on the UHMWPE surfaces.

  20. Baldwin Effect and Additional BLR Component in AGN with Superluminal Jets

    Energy Technology Data Exchange (ETDEWEB)

    Patiño-Álvarez, Víctor M.; Torrealba, Janet; Chavushyan, Vahram [Instituto Nacional de Astrofísica, Óptica y Electrónica, Puebla (Mexico); Cruz-González, Irene [Instituto de Astronomía, Universidad Nacional Autónoma de México, Mexico City (Mexico); Arshakian, Tigran [Physikalisches Institut, Universität zu Köln, Köln (Germany); Byurakan Astrophysical Observatory, Byurakan (Armenia); Isaac Newton Institute of Chile in Estern Europe and Eurasia, Armenian Branch, Santiago (Chile); León-Tavares, Jonathan [Instituto Nacional de Astrofísica, Óptica y Electrónica, Puebla (Mexico); Popović, Luka, E-mail: chavushyanv@gmail.com [Astronomical Observatory, Belgrade (Serbia)

    2016-06-02

    We study the Baldwin Effect (BE) in 96 core-jet blazars with optical and ultraviolet spectroscopic data from a radio-loud AGN sample obtained from the MOJAVE 2 cm survey. A statistical analysis is presented of the equivalent widths (W{sub λ}) of emission lines Hβ λ4861, Mg II λ2798, C IV λ1549, and continuum luminosities at 5100 Å, 3000 Å, and 1350 Å. The BE is found statistically significant (with confidence level c.l.≥ 95%) in Hβ and C IV emission lines, while for Mg II the trend is slightly less significant (c.l. = 94.5%). The slopes of the BE in the studied samples for Hβ and Mg II are found steeper and with statistically significant difference than those of a comparison radio-quiet sample. We present simulations of the expected BE slopes produced by the contribution to the total continuum of the non-thermal boosted emission from the relativistic jet, and by variability of the continuum components. We find that the slopes of the BE between radio-quiet and radio-loud AGN should not be different, under the assumption that the broad line is only being emitted by the canonical broad line region around the black hole. We discuss that the BE slope steepening in radio AGN is due to a jet associated broad-line region.

  1. Evidence for ultrafast outflows in radio-quiet AGNs - III. Location and energetics

    Science.gov (United States)

    Tombesi, F.; Cappi, M.; Reeves, J. N.; Braito, V.

    2012-05-01

    Using the results of a previous X-ray photoionization modelling of blueshifted Fe K absorption lines on a sample of 42 local radio-quiet AGNs observed with XMM-Newton, in this Letter we estimate the location and energetics of the associated ultrafast outflows (UFOs). Due to significant uncertainties, we are essentially able to place only lower/upper limits. On average, their location is in the interval ˜0.0003-0.03 pc (˜ 102-104rs) from the central black hole, consistent with what is expected for accretion disc winds/outflows. The mass outflow rates are constrained between ˜0.01 and 1 M⊙ yr-1, corresponding to >rsim5-10 per cent of the accretion rates. The average lower/upper limits on the mechanical power are log? 42.6-44.6 erg s-1. However, the minimum possible value of the ratio between the mechanical power and bolometric luminosity is constrained to be comparable or higher than the minimum required by simulations of feedback induced by winds/outflows. Therefore, this work demonstrates that UFOs are indeed capable to provide a significant contribution to the AGN cosmological feedback, in agreement with theoretical expectations and the recent observation of interactions between AGN outflows and the interstellar medium in several Seyfert galaxies.

  2. Evidence for Ultra-Fast Outflows in Radio-Quiet AGNs: III - Location and Energetics

    Science.gov (United States)

    Tombesi, F.; Cappi, M.; Reeves, J. N.; Braito, V.

    2012-01-01

    Using the results of a previous X-ray photo-ionization modelling of blue-shifted Fe K absorption lines on a sample of 42 local radio-quiet AGNs observed with XMM-Newton, in this letter we estimate the location and energetics of the associated ultrafast outflows (UFOs). Due to significant uncertainties, we are essentially able to place only lower/upper limits. On average, their location is in the interval approx.0.0003-0.03pc (approx.10(exp 2)-10(exp 4)tau(sub s) from the central black hole, consistent with what is expected for accretion disk winds/outflows. The mass outflow rates are constrained between approx.0.01- 1 Stellar Mass/y, corresponding to approx. or >5-10% of the accretion rates. The average lower-upper limits on the mechanical power are logE(sub K) approx. or = 42.6-44.6 erg/s. However, the minimum possible value of the ratio between the mechanical power and bolometric luminosity is constrained to be comparable or higher than the minimum required by simulations of feedback induced by winds/outflows. Therefore, this work demonstrates that UFOs are indeed capable to provide a significant contribution to the AGN r.osmological feedback, in agreement with theoretical expectations and the recent observation of interactions between AGN outflows and the interstellar medium in several Seyferts galaxies .

  3. Cosmic evolution of AGN with moderate-to-high radiative luminosity in the COSMOS field

    Science.gov (United States)

    Ceraj, L.; Smolčić, V.; Delvecchio, I.; Delhaize, J.; Novak, M.

    2018-05-01

    We study the moderate-to-high radiative luminosity active galactic nuclei (HLAGN) within the VLA-COSMOS 3 GHz Large Project. The survey covers 2.6 square degrees centered on the COSMOS field with a 1σ sensitivity of 2.3 μJy/beam across the field. This provides the simultaneously largest and deepest radio continuum survey available to date with exquisite multi-wavelength coverage. The survey yields 10,830 radio sources with signal-to-noise ratios >=5. A subsample of 1,604 HLAGN is analyzed here. These were selected via a combination of X-ray luminosity and mid-infrared colors. We derive luminosity functions for these AGN and constrain their cosmic evolution out to a redshift of z ~ 6, for the first time decomposing the star formation and AGN contributions to the radio continuum emission in the AGN. We study the evolution of number density and luminosity density finding a peak at z ~ 1.5 followed by a decrease out to a redshift z ~ 6.

  4. GAS OUTFLOWS IN SEYFERT GALAXIES: EFFECTS OF STAR FORMATION VERSUS AGN FEEDBACK

    Energy Technology Data Exchange (ETDEWEB)

    Melioli, C.; Pino, E. M. de Gouveia Dal, E-mail: claudio.melioli@iag.usp.br, E-mail: dalpino@iag.usp.br [Department of Astronomy (IAG-USP), University of Sao Paulo (Brazil)

    2015-10-20

    Large-scale, weakly collimated outflows are very common in galaxies with large infrared luminosities. In complex systems in particular, where intense star formation (SF) coexists with an active galactic nucleus (AGN), it is not clear yet from observations whether the SF, the AGN, or both are driving these outflows. Accreting supermassive black holes are expected to influence their host galaxies through kinetic and radiative feedback processes, but in a Seyfert galaxy, where the energy emitted in the nuclear region is comparable to that of the body of the galaxy, it is possible that stellar activity is also playing a key role in these processes. In order to achieve a better understanding of the mechanisms driving the gas evolution especially at the nuclear regions of these galaxies, we have performed high-resolution three-dimensional hydrodynamical simulations with radiative cooling considering the feedback from both SF regions, including supernova (Type I and II) explosions and an AGN jet emerging from the central region of the active spiral galaxy. We computed the gas mass lost by the system, separating the role of each of these injection energy sources on the galaxy evolution, and found that at scales within 1 kpc an outflow can be generally established considering intense nuclear SF only. The jet alone is unable to drive a massive gas outflow, although it can sporadically drag and accelerate clumps of the underlying outflow to very high velocities.

  5. Baldwin Effect and Additional BLR Component in AGN with Superluminal Jets

    Directory of Open Access Journals (Sweden)

    Víctor Manuel Patiño Álvarez

    2016-06-01

    Full Text Available We study the Baldwin Effect (BE in 96 core-jet blazars with optical and ultraviolet spectroscopic data from a radio-loud AGN sample obtained from the MOJAVE 2cm survey. A statistical analysis is presented of the equivalent widths W_lambda of emission lines H beta 4861, Mg II 2798, C IV 1549, and continuum luminosities at 5100, 3000, and 1350 angstroms. The BE is found statistically significant (with confidence level c.l. > 95% in H beta and C IV emission lines, while for Mg II the trend is slightly less significant (c.l. = 94.5%. The slopes of the BE in the studied samples for H beta and Mg II are found steeper and with statistically significant difference than those of a comparison radio-quiet sample. We present simulations of the expected BE slopes produced by the contribution to the total continuum of the non-thermal boosted emission from the relativistic jet, and by variability of the continuum components. We find that the slopes of the BE between radio-quiet and radio-loud AGN should not be different, under the assumption that the broad line is only being emitted by the canonical broad line region around the black hole. We discuss that the BE slope steepening in radio AGN is due to a jet associated broad-line region.

  6. Watching AGN feedback at its birth: HST observations of nascent outflow host IC860

    Science.gov (United States)

    Alatalo, Katherine

    2016-10-01

    IC860 is a nearby IR-luminous early-type spiral with a unique set of properties: it is a shocked, poststarburst galaxy that hosts an AGN-driven neutral wind and a compact core of molecular gas. IC860 can serve as a rosetta stone for the early stages of triggering AGN feedback. We propose to use WFC3 on HST to obtain NUV, optical and near-IR imaging of IC860. We will create a spatially-resolved history of star formation quenching through SED-fitting of 7 requested broadband filters, and compare the spatially resolved star formation histories to in different positions within the underlying stellar features (such as spiral structure) that might define a narrative of how star formation is quenching in IC860. These observations will also resolve the super-star cluster sites to trace the most recent star formation. Finally, these observations will trace the mass of the outflow by building an absorption map of the dust. IC860 presents a unique opportunity to study a galaxy at an early stage of transitioning from blue spiral to red early-type galaxy, that also hosts an AGN-driven neutral wind and a compact, turbulent molecular gas core.

  7. Constraints on Black Hole Spin in a Sample of Broad Iron Line AGN

    Science.gov (United States)

    Brenneman, Laura W.; Reynolds, Christopher S.

    2008-01-01

    We present a uniform X-ray spectral analysis of nine type-1 active galactic nuclei (AGN) that have been previously found to harbor relativistically broadened iron emission lines. We show that the need for relativistic effects in the spectrum is robust even when one includes continuum "reflection" from the accretion disk. We then proceed to model these relativistic effects in order to constrain the spin of the supermassive black holes in these AGN. Our principal assumption, supported by recent simulations of geometrically-thin accretion disks, is that no iron line emission (or any associated Xray reflection features) can originate from the disk within the innermost stable circular orbit. Under this assumption, which tends to lead to constraints in the form of lower limits on the spin parameter, we obtain non-trivial spin constraints on five AGN. The spin parameters of these sources range from moderate (a approximates 0.6) to high (a > 0.96). Our results allow, for the first time, an observational constraint on the spin distribution function of local supermassive black holes. Parameterizing this as a power-law in dimensionless spin parameter (f(a) varies as absolute value of (a) exp zeta), we present the probability distribution for zeta implied by our results. Our results suggest 90% and 95% confidence limits of zeta > -0.09 and zeta > -0.3 respectively.

  8. New Insights on the Accretion Disk-Winds Connection in Radio-Loud AGNs from Suzaku

    Science.gov (United States)

    Tombesi, F.; Sambruna, R. M.; Reeves, J. N.; Braito, V.; Cappi, M.; Reynolds, S.; Mushotzky, R. F.

    2011-01-01

    From the spectral analysis of long Suzaku observations of five radio-loud AGNs we have been able to discover the presence of ultra-fast outflows with velocities ,,approx.0.1 c in three of them, namely 3C III, 3C 120 and 3C 390.3. They are consistent with being accretion disk winds/outflows. We also performed a follow-up on 3C III to monitor its outflow on approx.7 days time-scales and detected an anti-correlated variability of a possible relativistic emission line with respect to blue-shifted Fe K features, following a flux increase. This provides the first direct evidence for an accretion disc-wind connection in an AGN. The mass outflow rate of these outflows can be comparable to the accretion rate and their mechanical power can correspond to a significant fraction of the bolometric luminosity and is comparable to their typical jet power. Therefore, they can possibly play a significant role in the expected feedback from AGNs and can give us further clues on the relation between the accretion disk and the formation of winds/jets.

  9. NGC 3393: multi-component AGN feedback as seen by CHEERS

    Science.gov (United States)

    Maksym, W. Peter; Fabbiano, Giuseppina; Elvis, Martin; Karovska, Margarita; Raymond, John C.; Storchi-Bergmann, Thaisa; Paggi, Alessandro; Wang, Junfeng; Risaliti, Guido

    2017-01-01

    Due to its low density, moderate ionization, and weak kinematics, the narrow line region (NLR) of active galactic nuclei (AGN) provides poweful diagnostics for investigating AGN feedback. The CHandra Extended Emission line Region Survey (CHEERS) is the ultimate investigation into resolved feedback in the NLR. We present results from our CHEERS investigations of NGC 3393. By imaging extended X-ray line emission of NGC 3393 with Chandra and optical line emission with Hubble's narrow-band filters, we are able to map out the simultaneous impact of photoionization, jets and an AGN disk-wind. When resolved on scales of ~10s of parsecs, the NLR of NGC 3393 shows a complex multi-component medium. Diagnostic line mapping indicates a Low-ionization Emmision Line Region (LINER) cocoon surrounding the outflow-evacuated cavities (in optical) and surrounding the supports the presence of collisional plasma (in X-rays). These physically distinct constituent regions can only be resolved by the high-resolution imaging that Chandra and HST enable.

  10. Multiwavelength Studies of Dual AGN in the Swift/BAT Sample

    Science.gov (United States)

    Treister, Ezequiel; Privon, George; Sartori, Lia; Nagar, Neil; Bauer, Franz Erik; Schawinski, Kevin; Ricci, Claudio; U, Vivian; Comerford, Julie; Muller-Sanchez, Francisco; Evans, Aaron; Koss, Michael; Sanders, David B.; Urry, Meg; MODA Collaboration

    2018-01-01

    For the last 30 years there has been growing evidence for a strong connection between major galaxy mergers and simultaneous episodes ofstrong star formation and signicant central supermassive black hole (SMBH) growth. A natural consequence of this scenario is that dual Active Galactic Nuclei (AGN), i.e., systems in which the two nuclear SMBHs are growing simultaneously at separations survey aimed to study the multiwavelength properties of the dual AGN in the neary universe, z10 keV, obtained from the Swift-BAT extragalactic survey and complemented by NuSTAR observations. Our work focuses on the study of the physical properties of the ionized, atomic and molecular gas and the dust in confirmed dual AGN by combining observations with ALMA, VLT/MUSE and SINFONI and Keck/OSIRIS among others. In addition to providing general properties of this poulation, we will further focus on two remarkable systems, NGC6240 and Mrk 463. Both systems show evidence of large kpc-scale tidal features, complex gas dynamics and kinematical evidence for both inflows and outflows.These results clearly show the importance of performing high resolution multi wavelength studies covering kpc scales in order to understandthe complex connection between black hole growth and galaxy evolution in this critical phase.Support from this work has been provided by CONICYT FONDECYT 1160999 and PFB-06/2007.

  11. Alma observations of nearby luminous infrared galaxies with various agn energetic contributions using dense gas tracers

    Energy Technology Data Exchange (ETDEWEB)

    Imanishi, Masatoshi [Subaru Telescope, 650 North A' ohoku Place, Hilo, HI 96720 (United States); Nakanishi, Kouichiro, E-mail: masa.imanishi@nao.ac.jp [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2014-07-01

    We present the results of our ALMA Cycle 0 observations, using HCN/HCO{sup +}/HNC J = 4-3 lines, of six nearby luminous infrared galaxies with various energetic contributions from active galactic nuclei (AGNs) estimated from previous infrared spectroscopy. These lines are very effective for probing the physical properties of high-density molecular gas around the hidden energy sources in the nuclear regions of these galaxies. We find that HCN to HCO{sup +} J = 4-3 flux ratios tend to be higher in AGN-important galaxies than in starburst-dominated regions, as was seen at the J = 1-0 transition, while there is no clear difference in the HCN-to-HNC J = 4-3 flux ratios among observed sources. A galaxy with a starburst-type infrared spectral shape and very large molecular line widths shows a high HCN-to-HCO{sup +} J = 4-3 flux ratio, which could be due to turbulence-induced heating. We propose that enhanced HCN J = 4-3 emission relative to HCO{sup +} J = 4-3 could be used to detect more energetic activity than normal starbursts, including deeply buried AGNs, in dusty galaxy populations.

  12. THE CLUSTER AND FIELD GALAXY ACTIVE GALACTIC NUCLEUS FRACTION AT z = 1-1.5: EVIDENCE FOR A REVERSAL OF THE LOCAL ANTICORRELATION BETWEEN ENVIRONMENT AND AGN FRACTION

    International Nuclear Information System (INIS)

    Martini, Paul; Miller, E. D.; Bautz, M.; Brodwin, M.; Stanford, S. A.; Gonzalez, Anthony H.; Hickox, R. C.; Stern, D.; Eisenhardt, P. R.; Galametz, A.; Norman, D.; Dey, A.; Jannuzi, B. T.; Murray, S.; Jones, C.; Brown, M. J. I.

    2013-01-01

    The fraction of cluster galaxies that host luminous active galactic nuclei (AGNs) is an important probe of AGN fueling processes, the cold interstellar medium at the centers of galaxies, and how tightly black holes and galaxies co-evolve. We present a new measurement of the AGN fraction in a sample of 13 clusters of galaxies (M ≥ 10 14 M ☉ ) at 1 A = 3.0 +2.4 -1.4 % for AGNs with a rest-frame, hard X-ray luminosity greater than L X, H ≥ 10 44 erg s –1 . This fraction is measured relative to all cluster galaxies more luminous than M * 3.6 (z) + 1, where M * 3.6 (z) is the absolute magnitude of the break in the galaxy luminosity function at the cluster redshift in the IRAC 3.6 μm bandpass. The cluster AGN fraction is 30 times greater than the 3σ upper limit on the value for AGNs of similar luminosity at z ∼ 0.25, as well as more than an order of magnitude greater than the AGN fraction at z ∼ 0.75. AGNs with L X, H ≥ 10 43 erg s –1 exhibit similarly pronounced evolution with redshift. In contrast to the local universe, where the luminous AGN fraction is higher in the field than in clusters, the X-ray and MIR-selected AGN fractions in the field and clusters are consistent at 1 < z < 1.5. This is evidence that the cluster AGN population has evolved more rapidly than the field population from z ∼ 1.5 to the present. This environment-dependent AGN evolution mimics the more rapid evolution of star-forming galaxies in clusters relative to the field.

  13. Model of unified gauge fields; Le modele des champs de jauge unifies

    Energy Technology Data Exchange (ETDEWEB)

    Leite Lopes, J. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    1998-04-01

    In this work, we discuss the physical ideas which represents the basis for the unified gauge field model. Despite of the difficulties that we presently have for embodying in a natural manner muons and hadrons in that model, we have the feeling that we are on the way which seems to lead to the construction of a theory in which the Maxwell electromagnetic field and the Fermi weak interaction field are manifestations of a unique subjacent physical entity - the unified gauge fields. (author) 22 refs., 6 figs.

  14. Spitzer mid-IR spectroscopy of powerful 2Jy and 3CRR radio galaxies. II. AGN power indicators and unification

    Energy Technology Data Exchange (ETDEWEB)

    Dicken, D. [CEA-Saclay, F-91191 Gif-sur-Yvette (France); Tadhunter, C. [University of Sheffield, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Morganti, R. [ASTRON, P.O. Box 2, 7990 AA Dwingeloo (Netherlands); Axon, D.; Robinson, A.; Magagnoli, M. [Rochester Institute of Technology, 84 Lomb Memorial Drive, Rochester, NY 14623 (United States); Kharb, P. [Indian Institute of Astrophysics, II Block, Koramangala, Bangalore 560034 (India); Ramos Almeida, C. [Instituto de Astrofisica de Canarias (IAC), C/V ia Lactea, s/n, E-38205 La Laguna, Tenerife (Spain); Mingo, B. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Hardcastle, M. [School of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom); Nesvadba, N. P. H.; Singh, V. [Institut d' Astrophysique Spatiale, CNRS, Université Paris Sud, F-91405 Orsay (France); Kouwenhoven, M. B. N. [Kavli Institute for Astronomy and Astrophysics, Peking University, Yi He Yuan Lu 5, Haidian Qu, Beijing 100871 (China); Rose, M.; Spoon, H. [224 Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Inskip, K. J. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Holt, J., E-mail: daniel.dicken@cea.fr [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)

    2014-06-20

    It remains uncertain which continuum and emission line diagnostics best indicate the bolometric powers of active galactic nuclei (AGNs), especially given the attenuation caused by the circumnuclear material and the possible contamination by components related to star formation. Here we use mid-IR spectra along with multiwavelength data to investigate the merit of various diagnostics of AGN radiative power, including the mid-IR [Ne III] λ25.89 μm and [O IV] λ25.89 μm fine-structure lines, the optical [O III] λ5007 forbidden line, and mid-IR 24 μm, 5 GHz radio, and X-ray continuum emission, for complete samples of 46 2Jy radio galaxies (0.05 < z < 0.7) and 17 3CRR FRII radio galaxies (z < 0.1). We find that the mid-IR [O IV] line is the most reliable indicator of AGN power for powerful radio-loud AGNs. By assuming that the [O IV] is emitted isotropically, and comparing the [O III] and 24 μm luminosities of the broad- and narrow-line AGNs in our samples at fixed [O IV] luminosity, we show that the [O III] and 24 μm emission are both mildly attenuated in the narrow-line compared to the broad-line objects by a factor of ≈2. However, despite this attenuation, the [O III] and 24 μm luminosities are better AGN power indicators for our sample than either the 5 GHz radio or the X-ray continuum luminosities. We also detect the mid-IR 9.7 μm silicate feature in the spectra of many objects but not ubiquitously: at least 40% of the sample shows no clear evidence for these features. We conclude that, for the majority of powerful radio galaxies, the mid-IR lines are powered by AGN photoionization.

  15. The NuSTAR Serendipitous Survey: Hunting for the Most Extreme Obscured AGN at >10 keV

    Science.gov (United States)

    Lansbury, G. B.; Alexander, D. M.; Aird, J.; Gandhi, P.; Stern, D.; Koss, M.; Lamperti, I.; Ajello, M.; Annuar, A.; Assef, R. J.; Ballantyne, D. R.; Baloković, M.; Bauer, F. E.; Brandt, W. N.; Brightman, M.; Chen, C.-T. J.; Civano, F.; Comastri, A.; Del Moro, A.; Fuentes, C.; Harrison, F. A.; Marchesi, S.; Masini, A.; Mullaney, J. R.; Ricci, C.; Saez, C.; Tomsick, J. A.; Treister, E.; Walton, D. J.; Zappacosta, L.

    2017-09-01

    We identify sources with extremely hard X-ray spectra (I.e., with photon indices of {{Γ }}≲ 0.6) in the 13 deg2 NuSTAR serendipitous survey, to search for the most highly obscured active galactic nuclei (AGNs) detected at > 10 {keV}. Eight extreme NuSTAR sources are identified, and we use the NuSTAR data in combination with lower-energy X-ray observations (from Chandra, Swift XRT, and XMM-Newton) to characterize the broadband (0.5-24 keV) X-ray spectra. We find that all of the extreme sources are highly obscured AGNs, including three robust Compton-thick (CT; {N}{{H}}> 1.5× {10}24 cm-2) AGNs at low redshift (z< 0.1) and a likely CT AGN at higher redshift (z = 0.16). Most of the extreme sources would not have been identified as highly obscured based on the low-energy (< 10 keV) X-ray coverage alone. The multiwavelength properties (e.g., optical spectra and X-ray-mid-IR luminosity ratios) provide further support for the eight sources being significantly obscured. Correcting for absorption, the intrinsic rest-frame 10-40 keV luminosities of the extreme sources cover a broad range, from ≈ 5× {10}42 to 1045 erg s-1. The estimated number counts of CT AGNs in the NuSTAR serendipitous survey are in broad agreement with model expectations based on previous X-ray surveys, except for the lowest redshifts (z< 0.07), where we measure a high CT fraction of {f}{CT}{obs}={30}-12+16 % . For the small sample of CT AGNs, we find a high fraction of galaxy major mergers (50% ± 33%) compared to control samples of “normal” AGNs.

  16. LEP constraints on grand unified theories

    International Nuclear Information System (INIS)

    Sarkar, Utpal

    1993-01-01

    Recent developments on grand unified theories (GUTs) in the context of the LEP measurements of the coupling constants are reviewed. The three coupling constants at the electroweak scale have been measured at LEP quite precisely. One can allow these couplings to evolve with energy following the renormalization group equations for the various groups and find out whether all the coupling constants meet at any energy. It was pointed out that the minimal SU(5) grand unified theory fails to satisfy this test. However, various extensions of the theory are still allowed. These extensions include (i) supersymmetric SU(5) GUT, with some arbitrariness in the susy breaking scale arising from the threshold corrections, (ii) non-susy SU(5) GUTs with additional fermions as well as Higgs multiplets, which has masses of the order of TeV, and (iii) non-renormalizable effect of gravity with a fine tuned relation among the coupling constants at the unification energy. The LEP results also constrain GUTs with an intermediate symmetry breaking scale. By adjusting the intermediate symmetry breaking scale, one usually can have unification, but these theories get constrained. For example, the left-right symmetric theories coming from GUTs can be broken only at energies higher than about ∼10 10 GeV. This implies that if right handed gauge bosons are found at energies lower than this scale, then that will rule out the possibility of grand unification. Another recent interesting development on the subject, namely, low energy unification, is discussed in this context. All the coupling constants are unified at energies of the order of ∼10 8 GeV when they are embedded in an SU(15)GUT, with some particular symmetry breaking pattern. But even in this case the results of the intermediate symmetry breaking scale remain unchanged. (author). 16 refs., 3 figs

  17. A Unified Building Model for 3D Urban GIS

    Directory of Open Access Journals (Sweden)

    Ihab Hijazi

    2012-07-01

    Full Text Available Several tasks in urban and architectural design are today undertaken in a geospatial context. Building Information Models (BIM and geospatial technologies offer 3D data models that provide information about buildings and the surrounding environment. The Industry Foundation Classes (IFC and CityGML are today the two most prominent semantic models for representation of BIM and geospatial models respectively. CityGML has emerged as a standard for modeling city models while IFC has been developed as a reference model for building objects and sites. Current CAD and geospatial software provide tools that allow the conversion of information from one format to the other. These tools are however fairly limited in their capabilities, often resulting in data and information losses in the transformations. This paper describes a new approach for data integration based on a unified building model (UBM which encapsulates both the CityGML and IFC models, thus avoiding translations between the models and loss of information. To build the UBM, all classes and related concepts were initially collected from both models, overlapping concepts were merged, new objects were created to ensure the capturing of both indoor and outdoor objects, and finally, spatial relationships between the objects were redefined. Unified Modeling Language (UML notations were used for representing its objects and relationships between them. There are two use-case scenarios, both set in a hospital: “evacuation” and “allocating spaces for patient wards” were developed to validate and test the proposed UBM data model. Based on these two scenarios, four validation queries were defined in order to validate the appropriateness of the proposed unified building model. It has been validated, through the case scenarios and four queries, that the UBM being developed is able to integrate CityGML data as well as IFC data in an apparently seamless way. Constraints and enrichment functions are

  18. Cosmotopological relation for a unified field theory

    International Nuclear Information System (INIS)

    Bij, J. J. van der

    2007-01-01

    I present an argument, based on the topology of the universe, why there are three generations of fermions. The argument implies a preferred unified gauge group of SU(5), but with SO(10) representations of the fermions. The breaking pattern SU(5)→SU(3)xSU(2)xU(1) is preferred over the pattern SU(5)→SU(4)xU(1). On the basis of the argument one expects an asymmetry in the early universe microwave data, which might have been detected already

  19. General unifying features of controlled quantum phenomena

    International Nuclear Information System (INIS)

    Pechen, Alexander; Brif, Constantin; Wu, Rebing; Chakrabarti, Raj; Rabitz, Herschel

    2010-01-01

    Many proposals have been put forth for controlling quantum phenomena, including open-loop, adaptive feedback, and real-time feedback control. Each of these approaches has been viewed as operationally, and even physically, distinct from the others. This work shows that all such scenarios inherently share the same fundamental control features residing in the topology of the landscape relating the target physical observable to the applied controls. This unified foundation may provide a basis for development of hybrid control schemes that would combine the advantages of the existing approaches to achieve the best overall performance.

  20. Towards unifying inheritance and automatic program specialization

    DEFF Research Database (Denmark)

    Schultz, Ulrik Pagh

    2002-01-01

    and specialization of classes (inheritance) are considered different abstractions. We present a new programming language, Lapis, that unifies inheritance and program specialization at the conceptual, syntactic, and semantic levels. This paper presents the initial development of Lapis, which uses inheritance...... with covariant specialization to control the automatic application of program specialization to class members. Lapis integrates object-oriented concepts, block structure, and techniques from automatic program specialization to provide both a language where object-oriented designs can be e#ciently implemented...

  1. Leading gravitational corrections and a unified universe

    DEFF Research Database (Denmark)

    Codello, Alessandro; Jain, Rajeev Kumar

    2016-01-01

    Leading order gravitational corrections to the Einstein-Hilbert action can lead to a consistent picture of the universe by unifying the epochs of inflation and dark energy in a single framework. While the leading local correction induces an inflationary phase in the early universe, the leading...... nonlocal term leads to an accelerated expansion of the universe at the present epoch. We argue that both the leading UV and IR terms can be obtained within the framework of a covariant effective field theory of gravity. The perturbative gravitational corrections therefore provide a fundamental basis...

  2. TOWARDS A UNIFIED VIEW OF METAHEURISTICS

    Directory of Open Access Journals (Sweden)

    El-Ghazali Talbi

    2013-02-01

    Full Text Available This talk provides a complete background on metaheuristics and presents in a unified view the main design questions for all families of metaheuristics and clearly illustrates how to implement the algorithms under a software framework to reuse both the design and code. The key search components of metaheuristics are considered as a toolbox for: - Designing efficient metaheuristics (e.g. local search, tabu search, simulated annealing, evolutionary algorithms, particle swarm optimization, scatter search, ant colonies, bee colonies, artificial immune systems for optimization problems. - Designing efficient metaheuristics for multi-objective optimization problems. - Designing hybrid, parallel and distributed metaheuristics. - Implementing metaheuristics on sequential and parallel machines.

  3. Improvements on a Unified Dark Matter Model

    Directory of Open Access Journals (Sweden)

    Del Popolo A.

    2016-06-01

    Full Text Available We study, by means of a spherical collapse model, the effect of shear, rotation, and baryons on a generalized Chaplygin gas (gCg dominated universe. We show that shear, rotation, and the presence of baryons slow down the collapse compared to the simple spherical collapse model. The slowing down in the growth of density perturbation is able to solve the instability of the unified dark matter (UDM models described in previous papers (e.g. Sandvik et al. 2004 at the linear perturbation level, as also shown by a direct comparison of our model with previous results.

  4. The three constituencies of the state: why the state has lost unifying energy.

    Science.gov (United States)

    King, Desmond; Le Galès, Patrick

    2017-11-01

    We address resurgent populism by examining structural processes of state transformation in the UK, the US and France. Scholars stress the 'unifying energy of the state', a set of institutions and policies capable of limiting inequalities and defending legal regimes. One characteristic of modern Western statehood were packages of policies designed to integrate social groups and territories in part by ensuring common standards of provision and social citizenship across the nation state. This echoes James Scott's critical analysis of the modernist project of the state (1998). This 'unifying energy' had different origins including nationalist movements, combatting external influence or powers, war, and preparing citizens for the rigours of industrialization. Overcoming class differences and territorial differences (including cultural, social and economic differences) was a major source of mobilization to feed this 'unifying energy of the state' in France, Italy or Spain for instance. Political and cultural identities are related in significant part to respective nation states. We argue that this 'unifying energy' was an essential component of statehood in Europe and in the US. It is now largely lost. We explain why and the significance of its displacement. © London School of Economics and Political Science 2017.

  5. Unified approach to the study of solid fuel combustion characteristics at high airflow speeds

    Science.gov (United States)

    Vnuchkov, D. A.; Lukashevich, S. V.; Nalivaychenko, D. G.; Zvegintsev, V. I.

    2017-10-01

    The main objective of the research is the development of guidelines for a unified approach to testing the combustion of different solid fuels in gaseous oxidant high-speed flow, so that research outcomes could be presented in a standardized and cohesive form. All the experiments were performed on a special experimental installation designed for quantification of the burning characteristics of different fuels in a wide range of the airflow parameters at the same geometry of the combustion chamber.

  6. 77 FR 73322 - Revisions to the California State Implementation Plan, Monterey Bay Unified Air Pollution Control...

    Science.gov (United States)

    2012-12-10

    ...EPA is taking direct final action to approve revisions to the Monterey Bay Unified Air Pollution Control District (MBUAPCD) portion of the California State Implementation Plan (SIP). These revisions concern opacity standards related to multiple pollutants, including particulate matter (PM) emissions from several different types of sources, ranging from fugitive dust to gas turbines. We are approving a local rule that regulates these emission sources under the Clean Air Act (CAA or the Act).

  7. 77 FR 73392 - Revisions to the California State Implementation Plan, Monterey Bay Unified Air Pollution Control...

    Science.gov (United States)

    2012-12-10

    ...EPA is proposing to approve revisions to the Monterey Bay Unified Air Pollution Control District (MBUAPCD) portion of the California State Implementation Plan (SIP). This revision concerns opacity standards related to multiple pollutants, including particulate matter (PM) emissions from several different types of sources, ranging from fugitive dust to gas turbines. We are proposing to approve a local rule to regulate these emission sources under the Clean Air Act (CAA or the Act).

  8. Pseudo-Goldstone Higgs Doublets from Non-Vectorlike Grand Unified Higgs Sector

    CERN Document Server

    Hernández, A E Cárcamo

    2016-01-01

    We present a novel way of realizing the pseudo-Nambu-Goldstone boson mechanism for the doublet-triplet splitting in supersymmetric grand unified theories. The global symmetries of the Higgs sector are attributed to a non-vectorlike Higgs content, which is consistent with unbroken supersymmetry in a scenario with flat extra dimensions and branes. We also show how in such a model one can naturally obtain a realistic pattern for the Standard Model fermion masses and mixings.

  9. Deja vu: The Unified Command Plan of the Future Revisited

    Science.gov (United States)

    2011-05-19

    Approved for Public Release; Distribution is Unlimited Déjà vu : The Unified Command Plan of the Future Revisited A Monograph by Lieutenant...DD-MM-YYYY) 19-05-2011 2. REPORT TYPE Monograph 3. DATES COVERED (From - To) JUL 2010 – MAY 2011 4. TITLE AND SUBTITLE Déjà vu : The Unified...i SCHOOL OF ADVANCED MILITARY STUDIES MONOGRAPH APPROVAL Lieutenant Colonel Edward Francis Martignetti Title of Monograph: Déjà vu : The Unified

  10. A unified view of "how allostery works".

    Science.gov (United States)

    Tsai, Chung-Jung; Nussinov, Ruth

    2014-02-01

    The question of how allostery works was posed almost 50 years ago. Since then it has been the focus of much effort. This is for two reasons: first, the intellectual curiosity of basic science and the desire to understand fundamental phenomena, and second, its vast practical importance. Allostery is at play in all processes in the living cell, and increasingly in drug discovery. Many models have been successfully formulated, and are able to describe allostery even in the absence of a detailed structural mechanism. However, conceptual schemes designed to qualitatively explain allosteric mechanisms usually lack a quantitative mathematical model, and are unable to link its thermodynamic and structural foundations. This hampers insight into oncogenic mutations in cancer progression and biased agonists' actions. Here, we describe how allostery works from three different standpoints: thermodynamics, free energy landscape of population shift, and structure; all with exactly the same allosteric descriptors. This results in a unified view which not only clarifies the elusive allosteric mechanism but also provides structural grasp of agonist-mediated signaling pathways, and guides allosteric drug discovery. Of note, the unified view reasons that allosteric coupling (or communication) does not determine the allosteric efficacy; however, a communication channel is what makes potential binding sites allosteric.

  11. DataSpread: Unifying Databases and Spreadsheets.

    Science.gov (United States)

    Bendre, Mangesh; Sun, Bofan; Zhang, Ding; Zhou, Xinyan; Chang, Kevin ChenChuan; Parameswaran, Aditya

    2015-08-01

    Spreadsheet software is often the tool of choice for ad-hoc tabular data management, processing, and visualization, especially on tiny data sets. On the other hand, relational database systems offer significant power, expressivity, and efficiency over spreadsheet software for data management, while lacking in the ease of use and ad-hoc analysis capabilities. We demonstrate DataSpread, a data exploration tool that holistically unifies databases and spreadsheets. It continues to offer a Microsoft Excel-based spreadsheet front-end, while in parallel managing all the data in a back-end database, specifically, PostgreSQL. DataSpread retains all the advantages of spreadsheets, including ease of use, ad-hoc analysis and visualization capabilities, and a schema-free nature, while also adding the advantages of traditional relational databases, such as scalability and the ability to use arbitrary SQL to import, filter, or join external or internal tables and have the results appear in the spreadsheet. DataSpread needs to reason about and reconcile differences in the notions of schema, addressing of cells and tuples, and the current "pane" (which exists in spreadsheets but not in traditional databases), and support data modifications at both the front-end and the back-end. Our demonstration will center on our first and early prototype of the DataSpread, and will give the attendees a sense for the enormous data exploration capabilities offered by unifying spreadsheets and databases.

  12. Unifying hydrotropy under Gibbs phase rule.

    Science.gov (United States)

    Shimizu, Seishi; Matubayasi, Nobuyuki

    2017-09-13

    The task of elucidating the mechanism of solubility enhancement using hydrotropes has been hampered by the wide variety of phase behaviour that hydrotropes can exhibit, encompassing near-ideal aqueous solution, self-association, micelle formation, and micro-emulsions. Instead of taking a field guide or encyclopedic approach to classify hydrotropes into different molecular classes, we take a rational approach aiming at constructing a unified theory of hydrotropy based upon the first principles of statistical thermodynamics. Achieving this aim can be facilitated by the two key concepts: (1) the Gibbs phase rule as the basis of classifying the hydrotropes in terms of the degrees of freedom and the number of variables to modulate the solvation free energy; (2) the Kirkwood-Buff integrals to quantify the interactions between the species and their relative contributions to the process of solubilization. We demonstrate that the application of the two key concepts can in principle be used to distinguish the different molecular scenarios at work under apparently similar solubility curves observed from experiments. In addition, a generalization of our previous approach to solutes beyond dilution reveals the unified mechanism of hydrotropy, driven by a strong solute-hydrotrope interaction which overcomes the apparent per-hydrotrope inefficiency due to hydrotrope self-clustering.

  13. A Unified Theoretical Framework for Cognitive Sequencing.

    Science.gov (United States)

    Savalia, Tejas; Shukla, Anuj; Bapi, Raju S

    2016-01-01

    The capacity to sequence information is central to human performance. Sequencing ability forms the foundation stone for higher order cognition related to language and goal-directed planning. Information related to the order of items, their timing, chunking and hierarchical organization are important aspects in sequencing. Past research on sequencing has emphasized two distinct and independent dichotomies: implicit vs. explicit and goal-directed vs. habits. We propose a theoretical framework unifying these two streams. Our proposal relies on brain's ability to implicitly extract statistical regularities from the stream of stimuli and with attentional engagement organizing sequences explicitly and hierarchically. Similarly, sequences that need to be assembled purposively to accomplish a goal require engagement of attentional processes. With repetition, these goal-directed plans become habits with concomitant disengagement of attention. Thus, attention and awareness play a crucial role in the implicit-to-explicit transition as well as in how goal-directed plans become automatic habits. Cortico-subcortical loops basal ganglia-frontal cortex and hippocampus-frontal cortex loops mediate the transition process. We show how the computational principles of model-free and model-based learning paradigms, along with a pivotal role for attention and awareness, offer a unifying framework for these two dichotomies. Based on this framework, we make testable predictions related to the potential influence of response-to-stimulus interval (RSI) on developing awareness in implicit learning tasks.

  14. A Unified Theoretical Framework for Cognitive Sequencing

    Directory of Open Access Journals (Sweden)

    Tejas Savalia

    2016-11-01

    Full Text Available The capacity to sequence information is central to human performance. Sequencing ability forms the foundation stone for higher order cognition related to language and goal-directed planning. Information related to the order of items, their timing, chunking and hierarchical organization are important aspects in sequencing. Past research on sequencing has emphasized two distinct and independent dichotomies: implicit versus explicit and goal-directed versus habits. We propose a theoretical framework unifying these two streams. Our proposal relies on brain's ability to implicitly extract statistical regularities from the stream of stimuli and with attentional engagement organizing sequences explicitly and hierarchically. Similarly, sequences that need to be assembled purposively to accomplish a goal require engagement of attentional processes. With repetition, these goal-directed plans become habits with concomitant disengagement of attention. Thus attention and awareness play a crucial role in the implicit-to-explicit transition as well as in how goal-directed plans become automatic habits. Cortico-subcortical loops ─ basal ganglia-frontal cortex and hippocampus-frontal cortex loops ─ mediate the transition process. We show how the computational principles of model-free and model-based learning paradigms, along with a pivotal role for attention and awareness, offer a unifying framework for these two dichotomies. Based on this framework, we make testable predictions related to the potential influence of response-to-stimulus interval (RSI on developing awareness in implicit learning tasks.

  15. STUDYING FAINT ULTRA-HARD X-RAY EMISSION FROM AGN IN GOALS LIRGS WITH SWIFT/BAT

    International Nuclear Information System (INIS)

    Koss, Michael; Casey, Caitlin M.; Mushotzky, Richard; Veilleux, Sylvain; Baumgartner, Wayne; Tueller, Jack; Markwardt, Craig

    2013-01-01

    We present the first analysis of the all-sky Swift Burst Alert Telescope (BAT) ultra-hard X-ray (14-195 keV) data for a targeted list of objects. We find that the BAT data can be studied at three-times-fainter limits than in previous blind detection catalogs based on prior knowledge of source positions and using smaller energy ranges for source detection. We determine the active galactic nucleus (AGN) fraction in 134 nearby (z IR /L ☉ > 11.8) detected. The BAT AGN classification shows 97% (37/38) agreement with Chandra and XMM-Newton AGN classification using hardness ratios or detection of an iron Kα line. This confirms our statistical analysis and supports the use of the Swift/BAT all-sky survey to study fainter populations of any category of sources in the ultra-hard X-ray band. BAT AGNs in LIRGs tend to show higher column densities with 40% ± 9% showing 14-195 keV/2-10 keV hardness flux ratios suggestive of high or Compton-thick column densities (log N H > 24 cm –2 ), compared to only 12% ± 5% of non-LIRG BAT AGNs. We also find that using specific energy ranges of the BAT detector can yield additional sources over total band detections with 24% (5/21) of detections in LIRGs at 24-35 keV not detected at 14-195 keV.

  16. The combined effect of AGN and supernovae feedback in launching massive molecular outflows in high-redshift galaxies

    Science.gov (United States)

    Biernacki, Pawel; Teyssier, Romain

    2018-04-01

    We have recently improved our model of active galactic nucleus (AGN) by attaching the supermassive black hole (SMBH) to a massive nuclear star cluster (NSC). Here, we study the effects of this new model in massive, gas-rich galaxies with several simulations of different feedback recipes with the hydrodynamics code RAMSES. These simulations are compared to a reference simulation without any feedback, in which the cooling halo gas is quickly consumed in a burst of star formation. In the presence of strong supernovae (SN) feedback, we observe the formation of a galactic fountain that regulates star formation over a longer period, but without halting it. If only AGN feedback is considered, as soon as the SMBH reaches a critical mass, strong outflows of hot gas are launched and prevent the cooling halo gas from reaching the disc, thus efficiently halting star formation, leading to the so-called `quenching'. If both feedback mechanisms act in tandem, we observe a non-linear coupling, in the sense that the dense gas in the supernovae-powered galactic fountain is propelled by the hot outflow powered by the AGN at much larger radii than without AGN. We argue that these particular outflows are able to unbind dense gas from the galactic halo, thanks to the combined effect of SN and AGN feedback. We speculate that this mechanism occurs at the end of the fast growing phase of SMBH, and is at the origin of the dense molecular outflows observed in many massive high-redshift galaxies.

  17. Unified transform architecture for AVC, AVS, VC-1 and HEVC high-performance codecs

    Science.gov (United States)

    Dias, Tiago; Roma, Nuno; Sousa, Leonel

    2014-12-01

    A unified architecture for fast and efficient computation of the set of two-dimensional (2-D) transforms adopted by the most recent state-of-the-art digital video standards is presented in this paper. Contrasting to other designs with similar functionality, the presented architecture is supported on a scalable, modular and completely configurable processing structure. This flexible structure not only allows to easily reconfigure the architecture to support different transform kernels, but it also permits its resizing to efficiently support transforms of different orders (e.g. order-4, order-8, order-16 and order-32). Consequently, not only is it highly suitable to realize high-performance multi-standard transform cores, but it also offers highly efficient implementations of specialized processing structures addressing only a reduced subset of transforms that are used by a specific video standard. The experimental results that were obtained by prototyping several configurations of this processing structure in a Xilinx Virtex-7 FPGA show the superior performance and hardware efficiency levels provided by the proposed unified architecture for the implementation of transform cores for the Advanced Video Coding (AVC), Audio Video coding Standard (AVS), VC-1 and High Efficiency Video Coding (HEVC) standards. In addition, such results also demonstrate the ability of this processing structure to realize multi-standard transform cores supporting all the standards mentioned above and that are capable of processing the 8k Ultra High Definition Television (UHDTV) video format (7,680 × 4,320 at 30 fps) in real time.

  18. The Unified Language Testing Plan: Speaking Proficiency Test. Spanish and English Pilot Validation Studies. Report Number 1.

    Science.gov (United States)

    Thornton, Julie A.

    This report describes one segment of the Federal Language Testing Board's Unified Language Testing Plan (ULTP), the validation of speaking proficiency tests in Spanish and English. The ULTP is a project to increase standardization of foreign language proficiency measurement and promote sharing of resources among testing programs in the federal…

  19. New limit on logotropic unified dark energy models

    Directory of Open Access Journals (Sweden)

    V.M.C. Ferreira

    2017-07-01

    Full Text Available A unification of dark matter and dark energy in terms of a logotropic perfect dark fluid has recently been proposed, where deviations with respect to the standard ΛCDM model are dependent on a single parameter B. In this paper we show that the requirement that the linear growth of cosmic structures on comoving scales larger than 8h−1Mpc is not significantly affected with respect to the standard ΛCDM result provides the strongest limit to date on the model (B<6×10−7, an improvement of more than three orders of magnitude over previous upper limits on the value of B. We further show that this limit rules out the logotropic Unified Dark Energy model as a possible solution to the small scale problems of the ΛCDM model, including the cusp problem of Dark Matter halos or the missing satellite problem, as well as the original version of the model where the Planck energy density was taken as one of the two parameters characterizing the logotropic dark fluid.

  20. X-ray surveys - Weighting the dark matter haloes of X-ray AGN: towards a physical description of the accretion history of the Universe

    Science.gov (United States)

    Georgakakis, Antonis; Mountrichas, G.; Fanidakis, N.; Finoguenov, A.; Aegis Collaboration

    2012-09-01

    The masses of the dark matter haloes in which AGN live is powerful diagnostic of the conditions under which supermassive black holes form and evolve across cosmic time. A new clustering estimation method will be presented which requires spectroscopy only for the AGN and uses photometric redshift probability density functions for galaxies to determine the projected real-space AGN/galaxy cross-correlation function. Our method is superior to traditional AGN clustering estimators (e.g. auto-correlation function) because (i) random errors are significantly suppressed when counting AGN/galaxy pairs, (ii) the impact of sample variance is minimized, and (iii) the requirements for spectroscopy are minimal; only spectroscopic redshift measurements for the AGN are needed. This method is applied to the combined AEGIS, COSMOS and ECDFS fields to infer the bias and dark matter halo mass of moderate luminosity (Lx~10^43 erg/s/cm^2) X-ray AGN at z~1 (total of 400). Predictions from the GALFORM semi-analytic model will be compared to the observations to show that a combination of hot and cold-gas accretion (the latter triggered by disk instabilities in spirals rather than mergers) reproduce well the clustering properties of X-ray AGN over a range of redshifts and luminosities.

  1. The Radius-Luminosity Relationship for Active Galactic Nuclei: The Effect of Host-Galaxy Starlight on Luminosity Measurements. II. The Full Sample of Reverberation-Mapped AGNs

    DEFF Research Database (Denmark)

    Bentz, Misty C.; Peterson, Bradley M.; Netzer, Hagai

    2009-01-01

    We present high-resolution Hubble Space Telescope images of all 35 active galactic nuclei (AGNs) with optical reverberation-mapping results, which we have modeled to create a nucleus-free image of each AGN host galaxy. From the nucleus-free images, we determine the host-galaxy contribution to gro...

  2. THE LICK AGN MONITORING PROJECT 2011: SPECTROSCOPIC CAMPAIGN AND EMISSION-LINE LIGHT CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Barth, Aaron J. [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA, 92697-4575 (United States); Bennert, Vardha N. [Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407 (United States); Canalizo, Gabriela [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Filippenko, Alexei V.; Li, Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Gates, Elinor L. [Lick Observatory, P.O. Box 85, Mount Hamilton, CA 95140 (United States); Greene, Jenny E. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Malkan, Matthew A.; Treu, Tommaso [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States); Pancoast, Anna [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Sand, David J. [Texas Tech University, Physics Department, Box 41051, Lubbock, TX 79409-1051 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Boulevard, Pasadena, CA 91109 (United States); Woo, Jong-Hak [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Assef, Roberto J. [Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago (Chile); Bae, Hyun-Jin [Department of Astronomy and Center for Galaxy Evolution Research, Yonsei University, Seoul 120-749 (Korea, Republic of); Brewer, Brendon J. [Department of Statistics, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Cenko, S. Bradley [Astrophysics Science Division, NASA Goddard Space Flight Center, MC 661, Greenbelt, MD 20771 (United States); and others

    2015-04-15

    In the Spring of 2011 we carried out a 2.5 month reverberation mapping campaign using the 3 m Shane telescope at Lick Observatory, monitoring 15 low-redshift Seyfert 1 galaxies. This paper describes the observations, reductions and measurements, and data products from the spectroscopic campaign. The reduced spectra were fitted with a multicomponent model in order to isolate the contributions of various continuum and emission-line components. We present light curves of broad emission lines and the active galactic nucleus (AGN) continuum, and measurements of the broad Hβ line widths in mean and rms spectra. For the most highly variable AGNs we also measured broad Hβ line widths and velocity centroids from the nightly spectra. In four AGNs exhibiting the highest variability amplitudes, we detect anticorrelations between broad Hβ width and luminosity, demonstrating that the broad-line region “breathes” on short timescales of days to weeks in response to continuum variations. We also find that broad Hβ velocity centroids can undergo substantial changes in response to continuum variations; in NGC 4593, the broad Hβ velocity shifted by ∼250 km s{sup −1} over a 1 month period. This reverberation-induced velocity shift effect is likely to contribute a significant source of confusion noise to binary black hole searches that use multi-epoch quasar spectroscopy to detect binary orbital motion. We also present results from simulations that examine biases that can occur in measurement of broad-line widths from rms spectra due to the contributions of continuum variations and photon-counting noise.

  3. A SOFT X-RAY REVERBERATION LAG IN THE AGN ESO 113–G010

    International Nuclear Information System (INIS)

    Cackett, E. M.; Fabian, A. C.; Kara, E.; Zogbhi, A.; Reynolds, C.; Uttley, P.

    2013-01-01

    Reverberation lags have recently been discovered in a handful of nearby, variable active galactic nuclei (AGNs). Here, we analyze a ∼100 ks archival XMM-Newton observation of the highly variable AGN, ESO 113–G010, in order to search for lags between hard, 1.5-4.5 keV, and soft, 0.3-0.9 keV, energy X-ray bands. At the lowest frequencies available in the light curve (∼ –4 Hz), we find hard lags where the power-law-dominated hard band lags the soft band (where the reflection fraction is high). However, at higher frequencies in the range (2-3) × 10 –4 Hz we find a soft lag of –325 ± 89 s. The general evolution from hard to soft lags as the frequency increases is similar to other AGNs where soft lags have been detected. We interpret this soft lag as due to reverberation from the accretion disk, with the reflection component responding to variability from the X-ray corona. For a black hole mass of 7 × 10 6 M ☉ this corresponds to a light-crossing time of ∼9 R g /c; however, dilution effects mean that the intrinsic lag is likely longer than this. Based on recent black hole mass scaling for lag properties, the lag amplitude and frequency are more consistent with a black hole a few times more massive than the best estimates, though flux-dependent effects could easily add scatter this large.

  4. The origin of ultrafast outflows in AGN: Monte Carlo simulations of the wind in PDS 456

    Science.gov (United States)

    Hagino, Kouichi; Odaka, Hirokazu; Done, Chris; Gandhi, Poshak; Watanabe, Shin; Sako, Masao; Takahashi, Tadayuki

    2015-01-01

    Ultrafast outflows (UFOs) are seen in many AGN, giving a possible mode for AGN feedback on to the host galaxy. However, the mechanism(s) for the launch and acceleration of these outflows are currently unknown, with UV line driving apparently strongly disfavoured as the material along the line of sight is so highly ionized that it has no UV transitions. We revisit this issue using the Suzaku X-ray data from PDS 456, an AGN with the most powerful UFO seen in the local Universe. We explore conditions in the wind by developing a new 3D Monte Carlo code for radiation transport. The code only handles highly ionized ions, but the data show the ionization state of the wind is high enough that this is appropriate, and this restriction makes it fast enough to explore parameter space. We reproduce the results of earlier work, confirming that the mass-loss rate in the wind is around 30 per cent of the inferred inflow rate through the outer disc. We show for the first time that UV line driving is likely to be a major contribution to the wind acceleration. The mass-loss rate in the wind matches that predicted from a purely line driven system, and this UV absorption can take place out of the line of sight. Continuum driving should also play a role as the source is close to Eddington. This predicts that the most extreme outflows will be produced from the highest mass accretion rate flows on to high-mass black holes, as observed.

  5. IC 3639 - A New Bona Fide Compton-Thick AGN Unveiled By NuSTAR

    Science.gov (United States)

    Boorman, Peter G.; Gandhi, P.; Alexander, D. M.; Annuar, A.; Ballantyne, D. R.; Bauer, F.; Boggs, S. E.; Brandt, W. N.; Brightman, M.; Christensen, F. E.; hide

    2016-01-01

    We analyze high-quality NuSTAR observations of the local (z = 0.011) Seyfert 2 active galactic nucleus (AGN) IC 3639, in conjunction with archival Suzaku and Chandra data. This provides the first broadband X-ray spectral analysis of the source, spanning nearly two decades in energy (0.5-30 keV). Previous X-ray observations of the source below 10 keV indicated strong reflection/obscuration on the basis of a pronounced iron fluorescence line at 6.4 keV. The hard X-ray energy coverage of NuSTAR, together with self-consistent toroidal reprocessing models, enables direct broadband constraints on the obscuring column density of the source. We find the source to be heavily Compton-thick (CTK) with an obscuring column in excess of 3.6 x 10(exp 24) cm(exp -2), unconstrained at the upper end. We further find an intrinsic 2-10 keV luminosity of log(sub 10) (L(sub 2-10 keV) [erg s(exp -1)])= 43.4(+0.6/-1.1) to 90% confidence, almost 400 times the observed flux, and consistent with various multiwavelength diagnostics. Such a high ratio of intrinsic to observed flux, in addition to an Fe-K(alpha) fluorescence line equivalent width exceeding 2 keV, is extreme among known bona fide CTK AGNs, which we suggest are both due to the high level of obscuration present around IC 3639. Our study demonstrates that broadband spectroscopic modeling with NuSTAR enables large corrections for obscuration to be carried out robustly and emphasizes the need for improved modeling of AGN tori showing intense iron fluorescence.

  6. Ionized Outflows in 3-D Insights from Herbig-Haro Objects and Applications to Nearby AGN

    Science.gov (United States)

    Cecil, Gerald

    1999-01-01

    HST shows that the gas distributions of these objects are complex and clump at the limit of resolution. HST spectra have lumpy emission-line profiles, indicating unresolved sub-structure. The advantages of 3D over slits on gas so distributed are: robust flux estimates of various dynamical systems projected along lines of sight, sensitivity to fainter spectral lines that are physical diagnostics (reddening-gas density, T, excitation mechanisms, abundances), and improved prospects for recovery of unobserved dimensions of phase-space. These advantages al- low more confident modeling for more profound inquiry into underlying dynamics. The main complication is the effort required to link multi- frequency datasets that optimally track the energy flow through various phases of the ISM. This tedium has limited the number of objects that have been thoroughly analyzed to the a priori most spectacular systems. For HHO'S, proper-motions constrain the ambient B-field, shock velocity, gas abundances, mass-loss rates, source duty-cycle, and tie-ins with molecular flows. If the shock speed, hence ionization fraction, is indeed small then the ionized gas is a significant part of the flow energetics. For AGN'S, nuclear beaming is a source of ionization ambiguity. Establishing the energetics of the outflow is critical to determining how the accretion disk loses its energy. CXO will provide new constraints (especially spectral) on AGN outflows, and STIS UV-spectroscopy is also constraining cloud properties (although limited by extinction). HHO's show some of the things that we will find around AGN'S. I illustrate these points with results from ground-based and HST programs being pursued with collaborators.

  7. LLAMA: nuclear stellar properties of Swift-BAT AGN and matched inactive galaxies

    Science.gov (United States)

    Lin, Ming-Yi; Davies, R. I.; Hicks, E. K. S.; Burtscher, L.; Contursi, A.; Genzel, R.; Koss, M.; Lutz, D.; Maciejewski, W.; Müller-Sánchez, F.; Orban de Xivry, G.; Ricci, C.; Riffel, R.; Riffel, R. A.; Rosario, D.; Schartmann, M.; Schnorr-Müller, A.; Shimizu, T.; Sternberg, A.; Sturm, E.; Storchi-Bergmann, T.; Tacconi, L.; Veilleux, S.

    2018-02-01

    In a complete sample of local 14-195 keV selected active galactic nuclei (AGNs) and inactive galaxies, matched by their host galaxy properties, we study the spatially resolved stellar kinematics and luminosity distributions at near-infrared wavelengths on scales of 10-150 pc, using SINFONI on the VLT. In this paper, we present the first half of the sample, which comprises 13 galaxies, eight AGNs and five inactive galaxies. The stellar velocity fields show a disc-like rotating pattern, for which the kinematic position angle is in agreement with the photometric position angle obtained from large scale images. For this set of galaxies, the stellar surface brightness of the inactive galaxy sample is generally comparable to the matched sample of AGN, but extends to lower surface brightness. After removal of the bulge contribution, we find a nuclear stellar light excess with an extended nuclear disc structure, which exhibits a size-luminosity relation. While we expect the excess luminosity to be associated with a dynamically cooler young stellar population, we do not typically see a matching drop in dispersion. This may be because these galaxies have pseudo-bulges in which the intrinsic dispersion increases towards the centre. And although the young stars may have an impact in the observed kinematics, their fraction is too small to dominate over the bulge and compensate the increase in dispersion at small radii, so no dispersion drop is seen. Finally, we find no evidence for a difference in the stellar kinematics and nuclear stellar luminosity excess between these active and inactive galaxies.

  8. Introduction to Standardization Administration of China

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Brief Introduction of SAC Standardization Administration of the People's Republic of China (SAC) was established in April 2001 and authorized by the State Council to exercise administrative responsibilities by undertaking unified management, supervision and overall coordination of standardization works in China.

  9. 18–22 cm VLBA Observational Evidence for Toroidal B-Field Components in Six AGN Jets

    Directory of Open Access Journals (Sweden)

    Juliana Cristina Motter

    2016-08-01

    Full Text Available The formation of relativistic jets in Active Galactic Nuclei (AGN is related to accretion onto their central supermassive black holes, and magnetic (B fields are believed to play a central role in launching, collimating, and accelerating the jet streams from very compact regions out to kiloparsec scales. We present results of Faraday rotation studies based on Very Long Baseline Array (VLBA data obtained at 18–22 cm for six well known AGN (OJ 287, 3C 279, PKS 1510-089, 3C 345, BL Lac, and 3C 454.3, which probe projected distances out to tens of parsecs from the observed cores. We have identified statistically significant, monotonic, transverse Faraday rotation gradients across the jets of all but one of these sources, indicating the presence of toroidal B fields, which may be one component of helical B fields associated with these AGN jets.

  10. Evidence for ultra-fast outflows in radio-quiet AGNs: III - location and energetics

    OpenAIRE

    Tombesi, F.; Cappi, M.; Reeves, J. N.; Braito, V.

    2012-01-01

    Using the results of a previous X-ray photo-ionization modelling of blue-shifted Fe K absorption lines on a sample of 42 local radio-quiet AGNs observed with XMM-Newton, in this letter we estimate the location and energetics of the associated ultra-fast outflows (UFOs). Due to significant uncertainties, we are essentially able to place only lower/upper limits. On average, their location is in the interval ~0.0003-0.03pc (~10^2-10^4 r_s) from the central black hole, consistent with what is exp...

  11. The gravitational microlens influence on X-ray spectral line generated by an AGN accretion disc

    Directory of Open Access Journals (Sweden)

    Popović L.Č.

    2001-01-01

    Full Text Available The influence of gravitational microlensing on the X-ray spectral line profiles originated from a relativistic accretion disc has been studied. Using a disc model, we show that microlensing can induce noticeable changes in the line shapes when the Einstein ring radius associated with the microlens is of a size comparable to that of the accretion disc. Taking into account the relatively small size of the X-ray accretion disc, we found that compact objects (of about a Solar mass which belong to the bulge of the host galaxy can produce significant changes in the X-ray line profile of AGN.

  12. THE LICK AGN MONITORING PROJECT: REVERBERATION MAPPING OF OPTICAL HYDROGEN AND HELIUM RECOMBINATION LINES

    International Nuclear Information System (INIS)

    Bentz, Misty C.; Walsh, Jonelle L.; Barth, Aaron J.; Thornton, Carol E.; Yoshii, Yuzuru; Sakata, Yu; Minezaki, Takeo; Woo, Jong-Hak; Malkan, Matthew A.; Wang, Xiaofeng; Steele, Thea N.; Silverman, Jeffrey M.; Serduke, Frank J. D.; Li, Weidong; Lee, Nicholas; Treu, Tommaso; Street, Rachel A.; Hidas, Marton G.; Hiner, Kyle D.; Greene, Jenny E.

    2010-01-01

    We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3 m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z 6 -10 7 M sun and also the well-studied nearby active galactic nucleus (AGN) NGC 5548. Nine of the objects in the sample (including NGC 5548) showed optical variability of sufficient strength during the monitoring campaign to allow for a time lag to be measured between the continuum fluctuations and the response to these fluctuations in the broad Hβ emission, which we have previously reported. We present here the light curves for the Hα, Hγ, He II λ4686, and He I λ5876 emission lines and the time lags for the emission-line responses relative to changes in the continuum flux. Combining each emission-line time lag with the measured width of the line in the variable part of the spectrum, we determine a virial mass of the central supermassive black hole from several independent emission lines. We find that the masses are generally consistent within the uncertainties. The time-lag response as a function of velocity across the Balmer line profiles is examined for six of the AGNs. We find similar responses across all three Balmer lines for Arp 151, which shows a strongly asymmetric profile, and for SBS 1116+583A and NGC 6814, which show a symmetric response about zero velocity. For the other three AGNs, the data quality is somewhat lower and the velocity-resolved time-lag response is less clear. Finally, we compare several trends seen in the data set against the predictions from photoionization calculations as presented by Korista and Goad. We confirm several of their predictions, including an increase in responsivity and a decrease in the mean time lag as the excitation and ionization level for the species increases. Specifically, we find the time lags of the optical recombination lines to have weighted mean ratios of τ(Hα):τ(Hβ):τ(Hγ):τ(He I):τ(He II) = 1

  13. THE LICK AGN MONITORING PROJECT: RECALIBRATING SINGLE-EPOCH VIRIAL BLACK HOLE MASS ESTIMATES

    Energy Technology Data Exchange (ETDEWEB)

    Park, Daeseong; Woo, Jong-Hak [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Treu, Tommaso; Bennert, Vardha N. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Barth, Aaron J.; Walsh, Jonelle [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697-4575 (United States); Bentz, Misty C. [Department of Physics and Astronomy, Georgia State University Atlanta, GA 30303 (United States); Canalizo, Gabriela [Department of Physics and Astronomy, University of California, Riverside, 900 University Ave., Riverside, CA 92521 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Gates, Elinor [Lick Observatory, P.O. Box 85, Mount Hamilton, CA 95140 (United States); Greene, Jenny E. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Malkan, Matthew A., E-mail: woo@astro.snu.ac.kr [Department of Physics and Astronomy, University of California, Los Angeles, CA 90024 (United States)

    2012-03-01

    We investigate the calibration and uncertainties of black hole (BH) mass estimates based on the single-epoch (SE) method, using homogeneous and high-quality multi-epoch spectra obtained by the Lick Active Galactic Nucleus (AGN) Monitoring Project for nine local Seyfert 1 galaxies with BH masses <10{sup 8} M{sub Sun }. By decomposing the spectra into their AGNs and stellar components, we study the variability of the SE H{beta} line width (full width at half-maximum intensity, FWHM{sub H{beta}} or dispersion, {sigma}{sub H{beta}}) and of the AGN continuum luminosity at 5100 A (L{sub 5100}). From the distribution of the 'virial products' ({proportional_to} FWHM{sub H{beta}}{sup 2} L{sup 0.5}{sub 5100} or {sigma}{sub H{beta}}{sup 2} L{sup 0.5}{sub 5100}) measured from SE spectra, we estimate the uncertainty due to the combined variability as {approx}0.05 dex (12%). This is subdominant with respect to the total uncertainty in SE mass estimates, which is dominated by uncertainties in the size-luminosity relation and virial coefficient, and is estimated to be {approx}0.46 dex (factor of {approx}3). By comparing the H{beta} line profile of the SE, mean, and root-mean-square (rms) spectra, we find that the H{beta} line is broader in the mean (and SE) spectra than in the rms spectra by {approx}0.1 dex (25%) for our sample with FWHM{sub H{beta}} <3000 km s{sup -1}. This result is at variance with larger mass BHs where the difference is typically found to be much less than 0.1 dex. To correct for this systematic difference of the H{beta} line profile, we introduce a line-width dependent virial factor, resulting in a recalibration of SE BH mass estimators for low-mass AGNs.

  14. VizieR Online Data Catalog: Lick AGN monitoring 2011: light curves (Barth+, 2015)

    Science.gov (United States)

    Barth, A. J.; Bennert, V. N.; Canalizo, G.; Filippenko, A. V.; Gates, E. L.; Greene, J. E.; Li, W.; Malkan, M. A.; Pancoast, A.; Sand, D. J.; Stern, D.; Treu, T.; Woo, J.-H.; Assef, R. J.; Bae, H.-J.; Brewer, B. J.; Cenko, S. B.; Clubb, K. I.; Cooper, M. C.; Diamond-Stanic, A. M.; Hiner, K. D.; Honig, S. F.; Hsiao, E.; Kandrashoff, M. T.; Lazarova, M. S.; Nierenberg, A. M.; Rex, J.; Silverman, J. M.; Tollerud, E. J.; Walsh, J. L.

    2015-05-01

    This project was allocated 69 nights at the Lick 3m Shane telescope, distributed between 2011 March 27 and June 13. Observations were conducted using the Kast double spectrograph (3440-5515Å on the blue side and 5410-8200Å on the red side). In order to extend our light curves for two AGNs, we also requested additional observations from other observers using the Kast spectrograph: Mrk 50 from 2011 January through March, and Zw 229-015 in June and July. For Zw 229-015, three additional observations were taken 20-23 days after the end of our main campaign. See section 3. (2 data files).

  15. THE CLUSTER AND FIELD GALAXY ACTIVE GALACTIC NUCLEUS FRACTION AT z = 1-1.5: EVIDENCE FOR A REVERSAL OF THE LOCAL ANTICORRELATION BETWEEN ENVIRONMENT AND AGN FRACTION

    Energy Technology Data Exchange (ETDEWEB)

    Martini, Paul [Department of Astronomy and Center for Cosmology and Astroparticle Physics, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Miller, E. D.; Bautz, M. [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Brodwin, M. [Department of Physics and Astronomy, University of Missouri, 5110 Rockhill Road, Kansas City, MO 64110 (United States); Stanford, S. A. [Department of Physics, University of California, One Shields Avenue, Davis, CA 95616 (United States); Gonzalez, Anthony H. [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Hickox, R. C. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); Stern, D.; Eisenhardt, P. R. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Galametz, A. [INAF-Osservatorio di Roma, Via Frascati 33, I-00040 Monteporzio (Italy); Norman, D.; Dey, A. [NOAO, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Jannuzi, B. T. [Department of Astronomy and Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Murray, S.; Jones, C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Brown, M. J. I., E-mail: martini@astronomy.ohio-state.edu [School of Physics, Monash University, Clayton, Victoria 3800 (Australia)

    2013-05-01

    The fraction of cluster galaxies that host luminous active galactic nuclei (AGNs) is an important probe of AGN fueling processes, the cold interstellar medium at the centers of galaxies, and how tightly black holes and galaxies co-evolve. We present a new measurement of the AGN fraction in a sample of 13 clusters of galaxies (M {>=} 10{sup 14} M{sub Sun }) at 1 < z < 1.5 selected from the Spitzer/IRAC Shallow Cluster Survey, as well as the field fraction in the immediate vicinity of these clusters, and combine these data with measurements from the literature to quantify the relative evolution of cluster and field AGN from the present to z {approx} 3. We estimate that the cluster AGN fraction at 1 < z < 1.5 is f{sub A} = 3.0{sup +2.4}{sub -1.4}% for AGNs with a rest-frame, hard X-ray luminosity greater than L{sub X,{sub H}} {>=} 10{sup 44} erg s{sup -1}. This fraction is measured relative to all cluster galaxies more luminous than M{sup *}{sub 3.6}(z) + 1, where M{sup *}{sub 3.6}(z) is the absolute magnitude of the break in the galaxy luminosity function at the cluster redshift in the IRAC 3.6 {mu}m bandpass. The cluster AGN fraction is 30 times greater than the 3{sigma} upper limit on the value for AGNs of similar luminosity at z {approx} 0.25, as well as more than an order of magnitude greater than the AGN fraction at z {approx} 0.75. AGNs with L{sub X,{sub H}} {>=} 10{sup 43} erg s{sup -1} exhibit similarly pronounced evolution with redshift. In contrast to the local universe, where the luminous AGN fraction is higher in the field than in clusters, the X-ray and MIR-selected AGN fractions in the field and clusters are consistent at 1 < z < 1.5. This is evidence that the cluster AGN population has evolved more rapidly than the field population from z {approx} 1.5 to the present. This environment-dependent AGN evolution mimics the more rapid evolution of star-forming galaxies in clusters relative to the field.

  16. The shape of the cosmic X-ray background: nuclear starburst discs and the redshift evolution of AGN obscuration

    Science.gov (United States)

    Gohil, R.; Ballantyne, D. R.

    2018-04-01

    A significant number of active galactic nuclei (AGNs) are observed to be hidden behind dust and gas. The distribution of material around AGNs plays an important role in modelling the cosmic X-ray background (CXB), especially the fraction of type 2 AGNs (f2). One of the possible explanations for obscuration in Seyfert galaxies at intermediate redshifts is dusty starburst discs. We compute the two-dimensional (2D) hydrostatic structure of 768 nuclear starburst discs (NSDs) under various physical conditions and also the distribution of column density along the line of sight (NH) associated with these discs. Then the NH distribution is evolved with redshift by using the redshift-dependent distribution function of input parameters. Parameter f2 shows a strong positive evolution up to z = 2, but only a weak level of enhancement at higher z. The Compton-thin and Compton-thick AGN fractions associated with these starburst regions increase ∝ (1 + z)δ, where δ is estimated to be 1.12 and 1.45, respectively. The reflection parameter Rf associated with column density NH ≥ 1023.5 cm-2 extends from 0.13 at z = 0 to 0.58 at z = 4. A CXB model employing this evolving NH distribution indicates that more compact (Rout < 120 pc) NSDs provide a better fit to the CXB. In addition to `Seyfert-like' AGNs obscured by nuclear starbursts, we predict that 40-60 per cent of quasars must be Compton-thick to produce a peak of the CXB spectrum within the observational uncertainty. The predicted total number counts of AGNs in 8-24 keV bands are in fair agreement with observations from the Nuclear Spectroscopic Telescope Array (NuSTAR).

  17. Hilltop supernatural inflation and SUSY unified models

    Science.gov (United States)

    Kohri, Kazunori; Lim, C. S.; Lin, Chia-Min; Mimura, Yukihiro

    2014-01-01

    In this paper, we consider high scale (100TeV) supersymmetry (SUSY) breaking and realize the idea of hilltop supernatural inflation in concrete particle physics models based on flipped-SU(5)and Pati-Salam models in the framework of supersymmetric grand unified theories (SUSY GUTs). The inflaton can be a flat direction including right-handed sneutrino and the waterfall field is a GUT Higgs. The spectral index is ns = 0.96 which fits very well with recent data by PLANCK satellite. There is no both thermal and non-thermal gravitino problems. Non-thermal leptogenesis can be resulted from the decay of right-handed sneutrino which plays (part of) the role of inflaton.

  18. Hilltop supernatural inflation and SUSY unified models

    Energy Technology Data Exchange (ETDEWEB)

    Kohri, Kazunori [Cosmophysics Group, Theory Center, IPNS KEK, and The Graduate University for Advanced Studies (Sokendai), 1-1 Oho, Tsukuba, 305-0801 (Japan); Lim, C.S. [Department of Mathematics, Tokyo Woman' s Christian University, Tokyo, 167-8585 (Japan); Lin, Chia-Min [Department of Physics, Chuo University, Bunkyo-ku, Tokyo, 112 (Japan); Mimura, Yukihiro, E-mail: kohri@post.kek.jp, E-mail: lim@lab.twcu.ac.jp, E-mail: lin@chuo-u.ac.jp, E-mail: mimura@hep1.phys.ntu.edu.tw [Department of Physics, National Taiwan University, Taipei, 10617 Taiwan (China)

    2014-01-01

    In this paper, we consider high scale (100TeV) supersymmetry (SUSY) breaking and realize the idea of hilltop supernatural inflation in concrete particle physics models based on flipped-SU(5)and Pati-Salam models in the framework of supersymmetric grand unified theories (SUSY GUTs). The inflaton can be a flat direction including right-handed sneutrino and the waterfall field is a GUT Higgs. The spectral index is n{sub s} = 0.96 which fits very well with recent data by PLANCK satellite. There is no both thermal and non-thermal gravitino problems. Non-thermal leptogenesis can be resulted from the decay of right-handed sneutrino which plays (part of) the role of inflaton.

  19. Unifying flipped SU(5) in five dimensions

    International Nuclear Information System (INIS)

    Barr, S.M.; Dorsner, Ilja

    2002-01-01

    It is shown that embedding a four-dimensional flipped SU(5) model in a five-dimensional SO(10) model preserves the best features of both flipped SU(5) and SO(10). The missing partner mechanism, which naturally achieves both doublet-triplet splitting and suppression of d=5 proton decay operators, is realized as in flipped SU(5), while the gauge couplings are unified as in SO(10). The masses of down quarks and charged leptons, which are independent in flipped SU(5), are related by the SO(10). Distinctive patterns of quark and lepton masses can result. The gaugino mass M 1 is independent of M 3 and M 2 , which are predicted to be equal

  20. Covariant extensions and the nonsymmetric unified field

    International Nuclear Information System (INIS)

    Borchsenius, K.

    1976-01-01

    The problem of generally covariant extension of Lorentz invariant field equations, by means of covariant derivatives extracted from the nonsymmetric unified field, is considered. It is shown that the contracted curvature tensor can be expressed in terms of a covariant gauge derivative which contains the gauge derivative corresponding to minimal coupling, if the universal constant p, characterizing the nonsymmetric theory, is fixed in terms of Planck's constant and the elementary quantum of charge. By this choice the spinor representation of the linear connection becomes closely related to the spinor affinity used by Infeld and Van Der Waerden (Sitzungsber. Preuss. Akad. Wiss. Phys. Math. Kl.; 9:380 (1933)) in their generally covariant formulation of Dirac's equation. (author)

  1. SUGERE - a unified system for waste management

    International Nuclear Information System (INIS)

    Silva, Eliane Magalhaes Pereira da; Vasconcelos, Vanderley de; Senne Junior, Murillo; Jordao, Elizabete

    2005-01-01

    Generation and disposal of wastes has been responsible for many economical, ecological and public health problems. In order to manage hazardous wastes in an environment friendly manner, many technical and administrative procedures should be implemented, including prevention, control of generation, and final disposal. A software named SUGERE - a unified system for waste management - is being developed. It is an easy to use tool that integrates all the steps involved in hazardous and radioactive waste management. This system is intended to help generators, transporters and owners of treatment, storage and disposal facilities to manage hazardous and radioactive wastes, by assuring compliance with environmental laws and consumer requirements. This paper presents the current status of the SUGERE software, developed using Borland Delphi package. The nuclear industry is used as a reference for developing this work. (author)

  2. UniPOPS: Unified data reduction suite

    Science.gov (United States)

    Maddalena, Ronald J.; Garwood, Robert W.; Salter, Christopher J.; Stobie, Elizabeth B.; Cram, Thomas R.; Morgan, Lorrie; Vance, Bob; Hudson, Jerome

    2015-03-01

    UniPOPS, a suite of programs and utilities developed at the National Radio Astronomy Observatory (NRAO), reduced data from the observatory's single-dish telescopes: the Tucson 12-m, the Green Bank 140-ft, and archived data from the Green Bank 300-ft. The primary reduction programs, 'line' (for spectral-line reduction) and 'condar' (for continuum reduction), used the People-Oriented Parsing Service (POPS) as the command line interpreter. UniPOPS unified previous analysis packages and provided new capabilities; development of UniPOPS continued within the NRAO until 2004 when the 12-m was turned over to the Arizona Radio Observatory (ARO). The submitted code is version 3.5 from 2004, the last supported by the NRAO.

  3. A Unifying Theory of Biological Function.

    Science.gov (United States)

    van Hateren, J H

    2017-01-01

    A new theory that naturalizes biological function is explained and compared with earlier etiological and causal role theories. Etiological (or selected effects) theories explain functions from how they are caused over their evolutionary history. Causal role theories analyze how functional mechanisms serve the current capacities of their containing system. The new proposal unifies the key notions of both kinds of theories, but goes beyond them by explaining how functions in an organism can exist as factors with autonomous causal efficacy. The goal-directedness and normativity of functions exist in this strict sense as well. The theory depends on an internal physiological or neural process that mimics an organism's fitness, and modulates the organism's variability accordingly. The structure of the internal process can be subdivided into subprocesses that monitor specific functions in an organism. The theory matches well with each intuition on a previously published list of intuited ideas about biological functions, including intuitions that have posed difficulties for other theories.

  4. Hilltop supernatural inflation and SUSY unified models

    International Nuclear Information System (INIS)

    Kohri, Kazunori; Lim, C.S.; Lin, Chia-Min; Mimura, Yukihiro

    2014-01-01

    In this paper, we consider high scale (100TeV) supersymmetry (SUSY) breaking and realize the idea of hilltop supernatural inflation in concrete particle physics models based on flipped-SU(5)and Pati-Salam models in the framework of supersymmetric grand unified theories (SUSY GUTs). The inflaton can be a flat direction including right-handed sneutrino and the waterfall field is a GUT Higgs. The spectral index is n s = 0.96 which fits very well with recent data by PLANCK satellite. There is no both thermal and non-thermal gravitino problems. Non-thermal leptogenesis can be resulted from the decay of right-handed sneutrino which plays (part of) the role of inflaton

  5. Centrally managed unified shared virtual address space

    Science.gov (United States)

    Wilkes, John

    2018-02-13

    Systems, apparatuses, and methods for managing a unified shared virtual address space. A host may execute system software and manage a plurality of nodes coupled to the host. The host may send work tasks to the nodes, and for each node, the host may externally manage the node's view of the system's virtual address space. Each node may have a central processing unit (CPU) style memory management unit (MMU) with an internal translation lookaside buffer (TLB). In one embodiment, the host may be coupled to a given node via an input/output memory management unit (IOMMU) interface, where the IOMMU frontend interface shares the TLB with the given node's MMU. In another embodiment, the host may control the given node's view of virtual address space via memory-mapped control registers.

  6. OPC from data access to unified architecture

    CERN Document Server

    Lange, Jurgen; Burke, Thomas J

    2010-01-01

    OPC stands for Openness, Productivity, and Collaboration, symbolizing the new possibilities opening up in automation technology. The main objective of the new OPC generation Unified Architecture is to facilitate global interoperability and to define an information and data-exchange mechanism that is service oriented, multivendor, and cross-platform capable – from the field device on the shop floor to the ERP system on the factory level. This book includes information on: - the birth, objectives, and fundamentals of OPC and OPC UA, - the technical specifications that currently exist and those that are in preparation, - the procedures for designing and implementing components, - a transparent presentation of the technology through application possibilities and examples, and - the outlook for the future of OPC and OPC UA. Important perspectives and updates in this new edition include - the new era and the exciting application possibilities developing with OPC UA, - the new OPC UA specifications, - the devel...

  7. Introduction to Grand Unified Theories. 12

    International Nuclear Information System (INIS)

    Wali, K.C.

    1989-01-01

    This chapter presents an introduction into Grand Unified Theories. After a discussion of the general features to be expected in any such theory, and of the motivations for them, a detailed presentation of SU(5) theory is given. The group structures, particle multiplets, gauge and Higgs bosons are explained. The two stages of spontaneous symmetry breaking via the Higgs model, are calculated individually and in combination. Fermion mass matrices and relations between quark and lepton masses are derived. predictions of SU(5) theory, calculated using renormalization group methods, are derived. The chapter ends with discussions that bring together particle physics and cosmology, including the baryon asymmetry problem, phase transitions in the very early universe, and singularities like domain walls, vortex lines and monopoles. (author). 9 refs.; 4 figs.; 5 tabs

  8. On the History of Unified Field Theories

    Directory of Open Access Journals (Sweden)

    Goenner Hubert F.M.

    2004-01-01

    Full Text Available This article is intended to give a review of the history of the classical aspects of unified field theories in the 20th century. It includes brief technical descriptions of the theories suggested, short biographical notes concerning the scientists involved, and an extensive bibliography. The present first installment covers the time span between 1914 and 1933, i.e., when Einstein was living and working in Berlin - with occasional digressions into other periods. Thus, the main theme is the unification of the electromagnetic and gravitational fields augmented by short-lived attempts to include the matter field described by Schrödinger's or Dirac's equations. While my focus lies on the conceptual development of the field, by also paying attention to the interaction of various schools of mathematicians with the research done by physicists, some prosopocraphical remarks are included.

  9. Supersymmetric grand unified theories and cosmology

    International Nuclear Information System (INIS)

    Lazarides, G.; Shafi, Q.

    1983-01-01

    By examining the behavior of supersymmetric grand unified theories (GUT's) in the very early universe we find two classes of realistic models. In one of them supersymmetry is broken at or near superheavy GUT scale. The cosmological implications of such models are expected to be similar to those of nonsupersymmetric GUT's. In the second class of models, the superheavy GUT scale is related to the supersymmetry-breaking scale in the manner of Witten. Two types of cosmological scenarios appear possible in this case, either with or without an intermediate (new) inflationary phase. They can be experimentally distinguished, since the former predicts an absence and the latter an observable number density of superheavy monopoles. A mechanism for generating baryon asymmetry in such models is pointed out

  10. A unified approach to the Darwin approximation

    International Nuclear Information System (INIS)

    Krause, Todd B.; Apte, A.; Morrison, P. J.

    2007-01-01

    There are two basic approaches to the Darwin approximation. The first involves solving the Maxwell equations in Coulomb gauge and then approximating the vector potential to remove retardation effects. The second approach approximates the Coulomb gauge equations themselves, then solves these exactly for the vector potential. There is no a priori reason that these should result in the same approximation. Here, the equivalence of these two approaches is investigated and a unified framework is provided in which to view the Darwin approximation. Darwin's original treatment is variational in nature, but subsequent applications of his ideas in the context of Vlasov's theory are not. We present here action principles for the Darwin approximation in the Vlasov context, and this serves as a consistency check on the use of the approximation in this setting

  11. New ideas about unified field theory

    International Nuclear Information System (INIS)

    Gleiser, M.

    1986-01-01

    An outline of the physical concepts evolution is given from the ancient philosophers to the present time. With qualitative explanations about the meaning of the theories that is the milestones of these concepts evolution, it mentions the ideas which lead the studies to the conception of a unified field theory. Chronologically, it has brief information about the ideas of Laplace (mechanical determinism), Maxwell (the field concept), Einsten (the space-time structure), Heisenberg and Schroedinger (the quantum mechanics), Dirac (the relativistic quantum and the antiparticles), Gell-Mann (the quarks), Weinberg-Salam (Weak interactions and eletromagnetic unification), H. Georgi and S. Glashon (strong interactions plus Weinberg-Salam), Kaluza-Klein (a fifth space-time coordinate), and Zumino-Weiss (supersymmetry and supergravity). (G.D.F.) [pt

  12. Preface to a GUT (Grand Unified Theory)

    International Nuclear Information System (INIS)

    Honig, W.

    1982-01-01

    A Grand Unified Theory (GUT) is proposed exhibiting relativistic invariance and based on a physical model for vacuum space consisting of the superposition of oppositely charged continuous fluids. Models for the photon, electron, neutrino, proton, etc., consist of separate unique variations in the relative densities of the fluids and their flow patterns. This GUT is also based on the use of transfinite axiomatic number forms and on a concept of metrical relativity which hopefully reconciles the many logical dichotomies in and between Special Relativity and Quantum Mechanics. These ideas result in a number of experimental proposals and predicted results which appear to be underivable from present paradigms, first among which is a physical model for the hidden variable of Quantum Mechanics. It is on these features that attention should rest. (Auth.)

  13. Centrally managed unified shared virtual address space

    Energy Technology Data Exchange (ETDEWEB)

    Wilkes, John

    2018-02-13

    Systems, apparatuses, and methods for managing a unified shared virtual address space. A host may execute system software and manage a plurality of nodes coupled to the host. The host may send work tasks to the nodes, and for each node, the host may externally manage the node's view of the system's virtual address space. Each node may have a central processing unit (CPU) style memory management unit (MMU) with an internal translation lookaside buffer (TLB). In one embodiment, the host may be coupled to a given node via an input/output memory management unit (IOMMU) interface, where the IOMMU frontend interface shares the TLB with the given node's MMU. In another embodiment, the host may control the given node's view of virtual address space via memory-mapped control registers.

  14. Alternative Fuels Data Center: Mesa Unified School District Reaps Economic

    Science.gov (United States)

    and Environmental Benefits with Propane Buses Mesa Unified School District Reaps Economic and School District Reaps Economic and Environmental Benefits with Propane Buses on Facebook Tweet about Alternative Fuels Data Center: Mesa Unified School District Reaps Economic and Environmental Benefits with

  15. Unified SU(4) color models in ten dimensions

    International Nuclear Information System (INIS)

    Hanlon, B.E.; Joshi, G.C.

    1992-01-01

    Some aspects of constructing unified models with SU(4) as the color group via a unifying group defined in ten dimensions are examined. Four dimensional theories are recovered using the Coset Space Dimensional Reduction scheme. Candidate models are considered in order to highlight some of the difficulties in constructing realistic four dimensional theories. 30 refs

  16. A Unified Scaling Law in Spiral Galaxies.

    Science.gov (United States)

    Koda; Sofue; Wada

    2000-03-01

    We investigate the origin of a unified scaling relation in spiral galaxies. Observed spiral galaxies are spread on a plane in the three-dimensional logarithmic space of luminosity L, radius R, and rotation velocity V. The plane is expressed as L~&parl0;VR&parr0;alpha in the I passband, where alpha is a constant. On the plane, observed galaxies are distributed in an elongated region which looks like the shape of a surfboard. The well-known scaling relations L-V (Tully-Fisher [TF] relation), V-R (also the TF relation), and R-L (Freeman's law) can be understood as oblique projections of the surfboard-like plane into two-dimensional spaces. This unified interpretation of the known scaling relations should be a clue to understand the physical origin of all the relations consistently. Furthermore, this interpretation can also explain why previous studies could not find any correlation between TF residuals and radius. In order to clarify the origin of this plane, we simulate formation and evolution of spiral galaxies with the N-body/smoothed particle hydrodynamics method, including cooling, star formation, and stellar feedback. Initial conditions are set to 14 isolated spheres with two free parameters, such as mass and angular momentum. The cold dark matter (h=0.5, Omega0=1) cosmology is considered as a test case. The simulations provide the following two conclusions: (1) The slope of the plane is well reproduced but the zero point is not. This zero-point discrepancy could be solved in a low-density (Omega00.5) cosmology. (2) The surfboard-shaped plane can be explained by the control of galactic mass and angular momentum.

  17. Measuring Star-Formation Rates of AGNs and QSOs using a new calibration from Polycyclic Aromatic Hydrocarbon Emission

    Science.gov (United States)

    Papovich, Casey

    they re-emit a large fraction of the ionization radiation from ongoing star formation. Preliminary work using archival spectra from Spitzer show that the PAH luminosity scales linearly with the SFR with smaller scatter than "gold standard" SFR tracers, such as the (dust corrected) hydrogen emission. The PAH emission becomes important because they are destroyed by the hard UV radiation in the vicinity of accreting supermassive blackholes. Therefore, this makes the PAH emission extremely powerful: it has the unique ability to measure SFRs in galaxies with active supermassive black holes, where every other SFR indicator is contaminated by emission from the supermassive black hole. This objectives for this proposal are to (1) provide a robust recalibration of the SFR from the mid-IR PAH emission features using a large sample of star-forming galaxies in the Spitzer archive; (2) demonstrate the utility of the PAHs to derive valid SFRs from JWST observations, using archival Spitzer spectroscopy for distant galaxies strongly lensed gravitationally; finally, using a large sample of galaxies with Spitzer spectroscopy spanning a large range of total luminosity and AGN activity (from pure starbursts to quasars) to (3) measure the distribution function of the luminosity of star-formation, AGN, and test how these vary with total luminosity and redshift. Theoretical models make strong predictions for this distribution function. Comparing the data to these predictions allows us to test these models directly.

  18. The first 62 AGNs observed with SDSS-IV MaNGA - I. Their characterization and definition of a control sample

    Science.gov (United States)

    Rembold, Sandro B.; Shimoia, Jáderson S.; Storchi-Bergmann, Thaisa; Riffel, Rogério; Riffel, Rogemar A.; Mallmann, Nícolas D.; do Nascimento, Janaína C.; Moreira, Thales N.; Ilha, Gabriele S.; Machado, Alice D.; Cirolini, Rafael; da Costa, Luiz N.; Maia, Marcio A. G.; Santiago, Basílio X.; Schneider, Donald P.; Wylezalek, Dominika; Bizyaev, Dmitry; Pan, Kaike; Müller-Sánchez, Francisco

    2017-12-01

    We report the characterization of the first 62 Mapping Nearby Galaxies at the Apache Point Observatory active galactic nuclei (AGNs) hosts and the definition of a control sample of non-active galaxies. This control sample was selected in order to match the AGN hosts in terms of stellar mass, redshift, visual morphology and inclination. The stellar masses are in the range 9.4AGN sample is mostly comprised low-luminosity AGN, with only 17 'strong AGN' with L([O III]λ 5007°_A ≥ 3.8× 10^{40} erg s^{-1}. The inner 1-3 kpc of the control sample galaxies are dominated by the oldest (≥ 4 Gyr) component, with a small contribution of intermediate age and young stars (<940 Myr). Examining the relationship between the stellar population properties and L([O III]}), we find that with increasing L([O III]), the AGN exhibit a decreasing contribution from the oldest stellar population relative to control galaxies and an increasing contribution from the younger components (∼40 Myr). We also find a correlation of the mean age differences (AGN-control) with L([O III]), in the sense that more luminous AGNs are younger than the control objects, while the low-luminosity AGNs are older. These results support a connection between the growth of the galaxy bulge via formation of new stars and the growth of the Supermassive Black Hole via accretion in the AGN phase.

  19. UUI: Reusable Spatial Data Services in Unified User Interface at NASA GES DISC

    Science.gov (United States)

    Petrenko, Maksym; Hegde, Mahabaleshwa; Bryant, Keith; Pham, Long B.

    2016-01-01

    Unified User Interface (UUI) is a next-generation operational data access tool that has been developed at Goddard Earth Sciences Data and Information Services Center(GES DISC) to provide a simple, unified, and intuitive one-stop shop experience for the key data services available at GES DISC, including subsetting (Simple Subset Wizard -SSW), granule file search (Mirador), plotting (Giovanni), and other legacy spatial data services. UUI has been built based on a flexible infrastructure of reusable web services self-contained building blocks that can easily be plugged into spatial applications, including third-party clients or services, to easily enable new functionality as new datasets and services become available. In this presentation, we will discuss our experience in designing UUI services based on open industry standards. We will also explain how the resulting framework can be used for a rapid development, deployment, and integration of spatial data services, facilitating efficient access and dissemination of spatial data sets.

  20. Supersymmetric grand unified theories from quarks to strings via SUSY GUTs

    CERN Document Server

    Raby, Stuart

    2017-01-01

    These course-tested lectures provide a technical introduction to Supersymmetric Grand Unified Theories (SUSY GUTs), as well as a personal view on the topic by one of the pioneers in the field. While the Standard Model of Particle Physics is incredibly successful in describing the known universe it is, nevertheless, an incomplete theory with many free parameters and open issues. An elegant solution to all of these quandaries is the proposed theory of SUSY GUTs. In a GUT, quarks and leptons are related in a simple way by the unifying symmetry and their electric charges are quantized, further the relative strength of the strong, weak and electromagnetic forces are predicted. SUSY GUTs additionally provide a framework for understanding particle masses and offer candidates for dark matter. Finally, with the extension of SUSY GUTs to string theory, a quantum-mechanically consistent unification of the four known forces (including gravity) is obtained. The book is organized in three sections: the first section contai...

  1. UUI: Reusable Spatial Data Services in Unified User Interface at NASA GES DISC

    Science.gov (United States)

    Petrenko, M.; Hegde, M.; Bryant, K.; Pham, L.

    2016-12-01

    Unified User Interface (UUI) is a next-generation operational data access tool that has been developed at Goddard Earth Sciences Data and Information Services Center (GES DISC) to provide a simple, unified, and intuitive one-stop shop experience for the key data services available at GES DISC, including subsetting (Simple Subset Wizard - SSW), granule file search (Mirador), plotting (Giovanni), and other legacy spatial data services. UUI has been built based on a flexible infrastructure of reusable web services - self-contained building blocks that can easily be plugged into spatial applications, including third-party clients or services, to easily enable new functionality as new datasets and services become available. In this presentation, we will discuss our experience in designing UUI services based on open industry standards. We will also explain how the resulting framework can be used for a rapid development, deployment, and integration of spatial data services, facilitating efficient access and dissemination of spatial data sets.

  2. Coral Reef and Hardbottom from Unified Florida Reef Tract Map (NODC Accession 0123059)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a subset of the Unified Map representing Coral reef and Hardbottom areas. Version 1.1 - December 2013. The Unified Florida Reef Tract Map (Unified...

  3. The effect of size-control policy on unified energy and carbon efficiency for Chinese fossil fuel power plants

    International Nuclear Information System (INIS)

    Zhang, Ning; Kong, Fanbin; Choi, Yongrok; Zhou, P.

    2014-01-01

    This paper examines the effect of size control policy on the energy and carbon efficiency for Chinese fossil fuel power industry. For this purpose, we propose two non-radial directional distance functions for energy/carbon efficiency analysis of fossil fuel electricity generation. One is named a total-factor directional distance function that incorporates the inefficiency of all input and output factors to measure the unified (operational and environmental) efficiency of fossil fuel power plants, and the other is called an energy–environmental directional distance function that can be used to measure the energy–environmental performance of fossil fuel electric power plants. Several standardized indicators for measuring unified efficiency and energy–environmental performance are derived from the two directional distance functions. An empirical study of 252 fossil fuel power plants in China is conducted by using the proposed approach. Our empirical results show that there exists a significant positive relationship between the plant size and unified efficiency, the five state-owned companies show lower unified efficiency and energy–environmental performance than other companies. It is suggested that Chinese government might need to consider private incentives and deregulation for its state-owned enterprises to improve their performance proactively. - Highlights: • Two non-radial directional distance functions are presented for energy/carbon efficiency analysis. • An empirical study of 252 fossil fuel power plants in China is conducted. • The five state-owned companies show lower unified efficiency and energy–environmental performance

  4. NGC 741—Mergers and AGN Feedback on a Galaxy-group Scale

    Energy Technology Data Exchange (ETDEWEB)

    Schellenberger, G.; Vrtilek, J. M.; David, L.; O’Sullivan, E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Giacintucci, S. [Naval Research Laboratory, 4555 Overlook Avenue SW, Code 7213, Washington, DC 20375 (United States); Johnston-Hollitt, M.; Duchesne, S. W. [School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, 6140 (New Zealand); Raychaudhury, S., E-mail: gerrit.schellenberger@cfa.harvard.edu [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India)

    2017-08-10

    Low-mass galaxy cluster systems and groups will play an essential role in upcoming cosmological studies, such as those to be carried out with eROSITA. Though the effects of active galactic nuclei (AGNs) and merging processes are of special importance to quantify biases like selection effects or deviations from hydrostatic equilibrium, they are poorly understood on the galaxy-group scale. We present an analysis of recent deep Chandra and XMM-Newton integrations of NGC 741 that provides an excellent example of a group with multiple concurrent phenomena: both an old central radio galaxy and a spectacular infalling head-tail source, strongly bent jets, a 100-kpc radio trail, intriguing narrow X-ray filaments, and gas-sloshing features. Supported principally by X-ray and radio continuum data, we address the merging history of the group, the nature of the X-ray filaments, the extent of gas-stripping from NGC 742, the character of cavities in the group, and the roles of the central AGN and infalling galaxy in heating the intra-group medium.

  5. A COMPACT GROUP OF GALAXIES AT Z = 2.48 HOSTING AN AGN-DRIVEN OUTFLOW

    Energy Technology Data Exchange (ETDEWEB)

    Shih, Hsin-Yi [Gemini Observatory, 670 N Aohoku Place, Hilo, HI 96720 (United States); Stockton, Alan, E-mail: jshih@gemini.edu, E-mail: stockton@ifa.hawaii.edu [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2015-12-10

    We present observations of a remarkable compact group of galaxies at z = 2.48. Four galaxies, all within 40 kpc of each other, surround a powerful high-redshift radio source. This group comprises two compact red passive galaxies and a pair of merging galaxies. One of the red galaxies, with an apparent stellar mass of 3.6 × 10{sup 11}M{sub ⊙} and an effective radius of 470 pc, is one of the most extreme examples of a massive quiescent compact galaxy found so far. One of the pair of merging galaxies hosts the active galactic nucleus (AGN) producing the large powerful radio structure. The merger is massive and enriched, consistent with the mass–metallicity relation expected at this redshift. Close to the merging nuclei, the emission lines exhibit broad and asymmetric profiles that suggest outflows powered either by a very young expanding radio jet or by AGN radiation. At ≳50 kpc from the system, we found a fainter extended-emission region that may be a part of a radio-jet-driven outflow.

  6. Disentangling Accretion Disk and Dust Emissions in the Infrared Spectrum of Type 1 AGN

    Energy Technology Data Exchange (ETDEWEB)

    Hernán-Caballero, Antonio [Departamento de Astrofísica y CC. de la Atmósfera, Facultad de CC. Físicas, Universidad Complutense de Madrid, Madrid (Spain); European Southern Observatory, Garching bei München (Germany); Hatziminaoglou, Evanthia [European Southern Observatory, Garching bei München (Germany); Alonso-Herrero, Almudena [Centro de Astrobiología (CSIC-INTA), Madrid (Spain); Mateos, Silvia, E-mail: a.hernan@ucm.es [Instituto de Física de Cantabria (CSIC-UC), Santander (Spain)

    2017-10-31

    We use a semi-empirical model to reproduce the 0.1–10 μm spectral energy distribution (SED) of a sample of 85 luminous quasars. In the model, the continuum emission from the accretion disk as well as the nebular lines are represented by a single empirical template (disk), where differences in the optical spectral index are reproduced by varying the amount of extinction. The near- and mid-infrared emission of the AGN-heated dust is modeled as the combination of two black-bodies (dust). The model fitting shows that the disk and dust components are remarkably uniform among individual quasars, with differences in the observed SED largely accounted for by varying levels of obscuration in the disk as well as differences in the relative luminosity of the disk and dust components. By combining the disk-subtracted SEDs of the 85 quasars, we generate a template for the 1–10 μm emission of the AGN-heated dust. Additionally, we use a sample of local Seyfert 1 galaxies with full spectroscopic coverage in the 0.37–39 μm range to demonstrate a method for stitching together spectral segments obtained with different PSF and extraction apertures. We show that the disk and dust templates obtained from luminous quasars also reproduce the optical-to-mid-infrared spectra of local Seyfert 1s when the contribution from the host galaxy is properly subtracted.

  7. Disentangling Accretion Disk and Dust Emissions in the Infrared Spectrum of Type 1 AGN

    Directory of Open Access Journals (Sweden)

    Antonio Hernán-Caballero

    2017-10-01

    Full Text Available We use a semi-empirical model to reproduce the 0.1–10 μm spectral energy distribution (SED of a sample of 85 luminous quasars. In the model, the continuum emission from the accretion disk as well as the nebular lines are represented by a single empirical template (disk, where differences in the optical spectral index are reproduced by varying the amount of extinction. The near- and mid-infrared emission of the AGN-heated dust is modeled as the combination of two black-bodies (dust. The model fitting shows that the disk and dust components are remarkably uniform among individual quasars, with differences in the observed SED largely accounted for by varying levels of obscuration in the disk as well as differences in the relative luminosity of the disk and dust components. By combining the disk-subtracted SEDs of the 85 quasars, we generate a template for the 1–10 μm emission of the AGN-heated dust. Additionally, we use a sample of local Seyfert 1 galaxies with full spectroscopic coverage in the 0.37–39 μm range to demonstrate a method for stitching together spectral segments obtained with different PSF and extraction apertures. We show that the disk and dust templates obtained from luminous quasars also reproduce the optical-to-mid-infrared spectra of local Seyfert 1s when the contribution from the host galaxy is properly subtracted.

  8. Demonstration of near-real-time accounting: the AGNS 1980-81 miniruns

    International Nuclear Information System (INIS)

    Dayem, H.A.; Baker, A.L.; Cobb, D.D.; Hakkila, E.A.; Ostenak, C.A.

    1984-01-01

    Near-real-time nuclear materials accounting was demonstrated in a series of experiments at the Allied-General Nuclear Services (AGNS) Barnwell Nuclear Fuels Plant. For each experiment, the second and third plutonium cycles were operated continuously for 1 wk processing uranium solutions. Process data were collected in near-real time by the AGNS computerized nuclear materials control and accounting system and were analyzed for uranium removals using decision analysis techniques. Although the measurement system primarily consisted of process-monitoring measurements that were not optimized for near-real-time accounting, the results of uranium-removal tests showed that removals and unexpected losses from the process area can be detected. Los Alamos used process-grade measurements to close hourly materials balances. Loss-detection sensitivities for 1 day of between 4 and 18 kg of uranium, at 50% detection probability and 2.5% false-alarm probability, were calculated for selected accounting areas. Using pulsed-column inventory estimators, we calculated a total four-column inventory that was within 10% of column dump measurements. Loss-detection sensitivity could be improved by incorporating online waste stream measurements, improving laboratory measurements for process streams, and refining the pulsed-column inventory estimates

  9. AGN Accretion Physics in the Time Domain: Survey Cadences, Stochastic Analysis, and Physical Interpretations

    Science.gov (United States)

    Moreno, Jackeline; Vogeley, Michael S.; Richards, Gordon; O'Brien, John T.; Kasliwal, Vishal

    2018-01-01

    We present rigorous testing of survey cadences (K2, SDSS, CRTS, & Pan-STARRS) for quasar variability science using a magnetohydrodynamics synthetic lightcurve and the canonical lightcurve from Kepler, Zw 229.15. We explain where the state of the art is in regards to physical interpretations of stochastic models (CARMA) applied to AGN variability. Quasar variability offers a time domain approach of probing accretion physics at the SMBH scale. Evidence shows that the strongest amplitude changes in the brightness of AGN occur on long timescales ranging from months to hundreds of days. These global behaviors can be constrained by survey data despite low sampling resolution. CARMA processes provide a flexible family of models used to interpolate between data points, predict future observations and describe behaviors in a lightcurve. This is accomplished by decomposing a signal into rise and decay timescales, frequencies for cyclic behavior and shock amplitudes. Characteristic timescales may point to length-scales over which a physical process operates such as turbulent eddies, warping or hotspots due to local thermal instabilities. We present the distribution of SDSS Stripe 82 quasars in CARMA parameters space that pass our cadence tests and also explain how the Damped Harmonic Oscillator model, CARMA(2,1), reduces to the Damped Random Walk, CARMA(1,0), given the data in a specific region of the parameter space.

  10. Variability analysis of AGN: a review of results using new statistical criteria

    Science.gov (United States)

    Zibecchi, L.; Andruchow, I.; Cellone, S. A.; Romero, G. E.; Combi, J. A.

    We present here a re-analysis of the variability results of a sample of active galactic nuclei (AGN), which have been observed on several sessions with the 2.15 m "Jorge Sahade" telescope (CASLEO), San Juan, Argentina, and whose results are published (Romero et al. 1999, 2000, 2002; Cellone et al. 2000). The motivation for this new analysis is the implementation, dur- ing the last years, of improvements in the statistical criteria applied, taking quantitatively into account the incidence of the photometric errors (Cellone et al. 2007). This work is framed as a first step in an integral study on the statistical estimators of AGN variability. This study is motivated by the great diversity of statistical tests that have been proposed to analyze the variability of these objects. Since we note that, in some cases, the results of the object variability depend on the test used, we attempt to make a com- parative study of the various tests and analyze, under the given conditions, which of them is the most efficient and reliable.

  11. A Mote in Andromeda's Disk: A Periodic AGN Behind M31

    Science.gov (United States)

    Dorn-Wallenstein, Trevor; Levesque, Emily; Ruan, John

    2018-01-01

    We present the discovery of multiple periodicities in J0045+41, a z≈0.215 AGN seen through a low-absorption region of M31. We obtained moderate resolution spectroscopy of J0045+41 using GMOS at Gemini-North. We use eigenspectra derived from principle component analyses of the SDSS galaxy and quasar catalogs to decompose the spectrum into host and AGN components, and estimate the luminosity and virial mass of the central engine. Residuals to our fit reveal a blue-shifted component to the broad Hα and Hβ lines at a relative velocity of ∼4800 km s-1. We search for evidence of periodicity using g-band photometry from the Palomar Transient Factory and find evidence for multiple periodicities ranging from ∼80-350 days. Two of the detected periods are in a 1:4 ratio, which is identical to the predictions of hydrodynamical simulations of binary supermassive black hole systems. If these signals arise due to such a system, J0045+41 is well within the gravitational wave regime. We calculate the time until inspiral due to gravitational radiation, assuming reasonable values of the mass ratio of the two black holes, and the anticipated gravitational strain in the context of forthcoming low-frequency gravitational wave observatories like the Square Kilometer Array.

  12. Rosen's (M,R) system in Unified Modelling Language.

    Science.gov (United States)

    Zhang, Ling; Williams, Richard A; Gatherer, Derek

    2016-01-01

    Robert Rosen's (M,R) system is an abstract biological network architecture that is allegedly non-computable on a Turing machine. If (M,R) is truly non-computable, there are serious implications for the modelling of large biological networks in computer software. A body of work has now accumulated addressing Rosen's claim concerning (M,R) by attempting to instantiate it in various software systems. However, a conclusive refutation has remained elusive, principally since none of the attempts to date have unambiguously avoided the critique that they have altered the properties of (M,R) in the coding process, producing merely approximate simulations of (M,R) rather than true computational models. In this paper, we use the Unified Modelling Language (UML), a diagrammatic notation standard, to express (M,R) as a system of objects having attributes, functions and relations. We believe that this instantiates (M,R) in such a way than none of the original properties of the system are corrupted in the process. Crucially, we demonstrate that (M,R) as classically represented in the relational biology literature is implicitly a UML communication diagram. Furthermore, since UML is formally compatible with object-oriented computing languages, instantiation of (M,R) in UML strongly implies its computability in object-oriented coding languages. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Unified Alignment of Protein-Protein Interaction Networks.

    Science.gov (United States)

    Malod-Dognin, Noël; Ban, Kristina; Pržulj, Nataša

    2017-04-19

    Paralleling the increasing availability of protein-protein interaction (PPI) network data, several network alignment methods have been proposed. Network alignments have been used to uncover functionally conserved network parts and to transfer annotations. However, due to the computational intractability of the network alignment problem, aligners are heuristics providing divergent solutions and no consensus exists on a gold standard, or which scoring scheme should be used to evaluate them. We comprehensively evaluate the alignment scoring schemes and global network aligners on large scale PPI data and observe that three methods, HUBALIGN, L-GRAAL and NATALIE, regularly produce the most topologically and biologically coherent alignments. We study the collective behaviour of network aligners and observe that PPI networks are almost entirely aligned with a handful of aligners that we unify into a new tool, Ulign. Ulign enables complete alignment of two networks, which traditional global and local aligners fail to do. Also, multiple mappings of Ulign define biologically relevant soft clusterings of proteins in PPI networks, which may be used for refining the transfer of annotations across networks. Hence, PPI networks are already well investigated by current aligners, so to gain additional biological insights, a paradigm shift is needed. We propose such a shift come from aligning all available data types collectively rather than any particular data type in isolation from others.

  14. Sfermion mass degeneracy, superconformal dynamics, and supersymmetric grand unified theories

    International Nuclear Information System (INIS)

    Kobayashi, Tatsuo; Noguchi, Tatsuya; Nakano, Hiroaki; Terao, Haruhiko

    2002-01-01

    We discuss issues in a scenario where hierarchical Yukawa couplings are generated through the strong dynamics of superconformal field theories (SCFTs). Independently of the mediation mechanism of supersymmetry breaking, the infrared convergence property of SCFTs can provide an interesting solution to the supersymmetric flavor problem; sfermion masses are suppressed around the decoupling scale of SCFTs and eventually become degenerate to some degree, thanks to family-independent radiative corrections governed by the gaugino masses of the minimal supersymmetric standard model (MSSM). We discuss under what conditions the degeneracy of the sfermion mass can be estimated in a simple manner. We also discuss the constraints from lepton flavor violations. We then explicitly study sfermion mass degeneracy within the framework of grand unified theories coupled to SCFTs. It is found that the degeneracy for right-handed sleptons becomes worse in the conventional SU(5) model than in the MSSM. On the other hand, in the flipped SU(5)xU(1) model, each right-handed lepton is still an SU(5) singlet, whereas the B-ino mass M 1 is determined by two independent gaugino masses of SU(5)xU(1). These two properties enable us to have an improved degeneracy for the right-handed sleptons. We also speculate on how further improvement can be obtained in the SCFT approach

  15. Producing EGS4 shower displays with the Unified Graphics System

    International Nuclear Information System (INIS)

    Cowan, R.F.

    1990-01-01

    The EGS4 Code System has been coupled with the SLAC Unified Graphics System in such a manner as to provide a means for displaying showers on UGS77-supported devices. This is most easily accomplished by attaching an auxiliary subprogram package (SHOWGRAF) to existing EGS4 User Codes and making use of a graphics display or a post-processor code called EGS4PL. SHOWGRAF may be used to create shower displays directly on interactive IBM 5080 color display devices, supporting three-dimensional rotations, translations, and zoom features, and providing illustration of particle types and energies by color and/or intensity. Alternatively, SHOWGRAF may be used to record a two-dimensional projection of the shower in a device-independent graphics file. The EGS4PL post-processor may then be used to convert this file into device-dependent graphics code for any UGS77-supported device. Options exist within EGS4PL that allow for two-dimensional translations and zoom, for creating line structure to indicate particle types and energies, and for optional display of particles by type. All of this is facilitated by means of the command processor EGS4PL EXEC together with new options (5080 and PDEV) with the standard EGS4IN EXEC routine for running EGS4 interactively under VM/SP. 6 refs

  16. Long-Term Monitoring of the Broad-Line Region Properties in a Selected Sample of AGN

    Energy Technology Data Exchange (ETDEWEB)

    Ilić, Dragana [Department of Astronomy, Faculty of Mathematics, University of Belgrade, Belgrade (Serbia); Shapovalova, Alla I. [Special Astrophysical Observatory, Russian Academy of Sciences, Nizhnii Arkhyz (Russian Federation); Popović, Luka Č. [Department of Astronomy, Faculty of Mathematics, University of Belgrade, Belgrade (Serbia); Astronomical Observatory, Belgrade (Serbia); Chavushyan, Vahram [Instituto Nacional de Astrofísica, Óptica y Electrónica, Puebla (Mexico); Burenkov, Alexander N. [Special Astrophysical Observatory, Russian Academy of Sciences, Nizhnii Arkhyz (Russian Federation); Kollatschny, Wolfram [Institut fuer Astrophysik, Universitaet Goettingen, Göttingen (Germany); Kovačević, Andjelka [Department of Astronomy, Faculty of Mathematics, University of Belgrade, Belgrade (Serbia); Marčeta-Mandić, Sladjana [Department of Astronomy, Faculty of Mathematics, University of Belgrade, Belgrade (Serbia); Astronomical Observatory, Belgrade (Serbia); Rakić, Nemanja [Department of Astronomy, Faculty of Mathematics, University of Belgrade, Belgrade (Serbia); Faculty of Science, University of Banjaluka, Banjaluka, Republic of Srpska (Bosnia and Herzegovina); La Mura, Giovanni; Rafanelli, Piero, E-mail: dilic@math.rs [Department of Physics and Astronomy, University of Padova, Padova (Italy)

    2017-09-14

    We present the results of the long-term optical monitoring campaign of active galactic nuclei (AGN) coordinated by the Special Astrophysical Observatory of the Russian Academy of Science. This campaign has produced a remarkable set of optical spectra, since we have monitored for several decades different types of broad-line (type 1) AGN, from a Seyfert 1, double-peaked line, radio loud and radio quiet AGN, to a supermassive binary black hole candidate. Our analysis of the properties of the broad line region (BLR) of these objects is based on the variability of the broad emission lines. We hereby give a comparative review of the variability properties of the broad emission lines and the BLR of seven different type 1 AGNs, emphasizing some important results, such as the variability rate, the BLR geometry, and the presence of the intrinsic Baldwin effect. We are discussing the difference and similarity in the continuum and emission line variability, focusing on what is the impact of our results to the supermassive black hole mass determination from the BLR properties.

  17. Long-Term Monitoring of the Broad-Line Region Properties in a Selected Sample of AGN

    Directory of Open Access Journals (Sweden)

    Dragana Ilić

    2017-09-01

    Full Text Available We present the results of the long-term optical monitoring campaign of active galactic nuclei (AGN coordinated by the Special Astrophysical Observatory of the Russian Academy of Science. This campaign has produced a remarkable set of optical spectra, since we have monitored for several decades different types of broad-line (type 1 AGN, from a Seyfert 1, double-peaked line, radio loud and radio quiet AGN, to a supermassive binary black hole candidate. Our analysis of the properties of the broad line region (BLR of these objects is based on the variability of the broad emission lines. We hereby give a comparative review of the variability properties of the broad emission lines and the BLR of seven different type 1 AGNs, emphasizing some important results, such as the variability rate, the BLR geometry, and the presence of the intrinsic Baldwin effect. We are discussing the difference and similarity in the continuum and emission line variability, focusing on what is the impact of our results to the supermassive black hole mass determination from the BLR properties.

  18. Modeling the Infrared Reverberation Response of the Circumnuclear Dusty Torus in AGNs: The Effects of Cloud Orientation and Anisotropic Illumination

    International Nuclear Information System (INIS)

    Almeyda, Triana; Robinson, Andrew; Richmond, Michael; Vazquez, Billy; Nikutta, Robert

    2017-01-01

    The obscuring circumnuclear torus of dusty molecular gas is one of the major components of active galactic nuclei (AGN). The torus can be studied by analyzing the time response of its infrared (IR) dust emission to variations in the AGN continuum luminosity, a technique known as reverberation mapping. The IR response is the convolution of the AGN ultraviolet/optical light curve with a transfer function that contains information about the size, geometry, and structure of the torus. Here, we describe a new computer model that simulates the reverberation response of a clumpy torus. Given an input optical light curve, the code computes the emission of a 3D ensemble of dust clouds as a function of time at selected IR wavelengths, taking into account light travel delays. We present simulated dust emission responses at 3.6, 4.5, and 30 μ m that explore the effects of various geometrical and structural properties, dust cloud orientation, and anisotropy of the illuminating radiation field. We also briefly explore the effects of cloud shadowing (clouds are shielded from the AGN continuum source). Example synthetic light curves have also been generated, using the observed optical light curve of the Seyfert 1 galaxy NGC 6418 as input. The torus response is strongly wavelength-dependent, due to the gradient in cloud surface temperature within the torus, and because the cloud emission is strongly anisotropic at shorter wavelengths. Anisotropic illumination of the torus also significantly modifies the torus response, reducing the lag between the IR and optical variations.

  19. Modeling the Infrared Reverberation Response of the Circumnuclear Dusty Torus in AGNs: The Effects of Cloud Orientation and Anisotropic Illumination

    Energy Technology Data Exchange (ETDEWEB)

    Almeyda, Triana; Robinson, Andrew; Richmond, Michael; Vazquez, Billy [School of Physics and Astronomy, Rochester Institute of Technology, Rochester, NY 14623 (United States); Nikutta, Robert, E-mail: tra3595@rit.edu [National Optical Astronomy Observatory, 950 N Cherry Ave, Tucson, AZ 85719 (United States)

    2017-07-01

    The obscuring circumnuclear torus of dusty molecular gas is one of the major components of active galactic nuclei (AGN). The torus can be studied by analyzing the time response of its infrared (IR) dust emission to variations in the AGN continuum luminosity, a technique known as reverberation mapping. The IR response is the convolution of the AGN ultraviolet/optical light curve with a transfer function that contains information about the size, geometry, and structure of the torus. Here, we describe a new computer model that simulates the reverberation response of a clumpy torus. Given an input optical light curve, the code computes the emission of a 3D ensemble of dust clouds as a function of time at selected IR wavelengths, taking into account light travel delays. We present simulated dust emission responses at 3.6, 4.5, and 30 μ m that explore the effects of various geometrical and structural properties, dust cloud orientation, and anisotropy of the illuminating radiation field. We also briefly explore the effects of cloud shadowing (clouds are shielded from the AGN continuum source). Example synthetic light curves have also been generated, using the observed optical light curve of the Seyfert 1 galaxy NGC 6418 as input. The torus response is strongly wavelength-dependent, due to the gradient in cloud surface temperature within the torus, and because the cloud emission is strongly anisotropic at shorter wavelengths. Anisotropic illumination of the torus also significantly modifies the torus response, reducing the lag between the IR and optical variations.

  20. Fermi LAT View of a Sample of Flaring γ-Ray AGNs S. Buson1,∗ , D ...

    Indian Academy of Sciences (India)

    and provide a comparison with AGNs seen in flaring state by the previous gamma- ... sients2. Weekly summary reports are also published in the 'Fermi Sky Blog'3. In addition, the FA–GSW on duty is in charge of triggering Target of Opportunity.

  1. Helical Magnetic Fields in AGN Jets Y. J. Chen1,2,∗ , G.-Y. Zhao1,2 ...

    Indian Academy of Sciences (India)

    Abstract. We establish a simple model to describe the helical mag- netic fields in AGN jets projected on the sky plane and the line-of-sight. This kind of profile has been detected in the polarimetric VLBI observa- tion of many blazar objects, suggesting the existence of helical magnetic fields in these sources. Key words.

  2. Spatial clustering and halo occupation distribution modelling of local AGN via cross-correlation measurements with 2MASS galaxies

    Science.gov (United States)

    Krumpe, Mirko; Miyaji, Takamitsu; Coil, Alison L.; Aceves, Hector

    2018-02-01

    We present the clustering properties and halo occupation distribution (HOD) modelling of very low redshift, hard X-ray-detected active galactic nuclei (AGN) using cross-correlation function measurements with Two-Micron All Sky Survey galaxies. Spanning a redshift range of 0.007 2MASS galaxies.

  3. Search for gamma-ray emitting AGN among unidentified Fermi-LAT sources using machine learning algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Doert, Marlene [Technische Universitaet Dortmund (Germany); Ruhr-Universitaet Bochum (Germany); Einecke, Sabrina [Technische Universitaet Dortmund (Germany); Errando, Manel [Barnard College, Columbia University, New York City (United States)

    2015-07-01

    The second Fermi-LAT source catalog (2FGL) is the deepest all-sky survey of the gamma-ray sky currently available to the community. Out of the 1873 catalog sources, 576 remain unassociated. We present a search for active galactic nuclei (AGN) among these unassociated objects, which aims at a reduction of the number of unassociated gamma-ray sources and a more complete characterization of the population of gamma-ray emitting AGN. Our study uses two complimentary machine learning algorithms which are individually trained on the gamma-ray properties of associated 2FGL sources and thereafter applied to the unassociated sample. The intersection of the two methods yields a high-confidence sample of 231 AGN candidate sources. We estimate the performance of the classification by taking inherent differences between the samples of associated and unassociated 2FGL sources into account. A search for infra-red counterparts and first results from follow-up studies in the X-ray band using Swift satellite data for a subset of our AGN candidates are also presented.

  4. RADIO PROPERTIES OF THE BAT AGNs: THE FIR–RADIO RELATION, THE FUNDAMENTAL PLANE, AND THE MAIN SEQUENCE OF STAR FORMATION

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Krista Lynne; Mushotzky, Richard F.; Vogel, Stuart; Shimizu, Thomas T. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Miller, Neal, E-mail: klsmith@astro.umd.edu [Department of Mathematics and Physics, Stevenson University, Stevenson, MD 21117 (United States)

    2016-12-01

    We conducted 22 GHz 1″ JVLA imaging of 70 radio-quiet active galactic nuclei (AGNs) from the Swift -BAT survey. We find radio cores in all but three objects. The radio morphologies of the sample fall into three groups: compact and core-dominated, extended, and jet-like. We spatially decompose each image into core flux and extended flux, and compare the extended radio emission with that predicted from previous Herschel observations using the canonical FIR–radio relation. After removing the AGN contribution to the FIR and radio flux densities, we find that the relation holds remarkably well despite the potentially different star formation physics in the circumnuclear environment. We also compare our core radio flux densities with predictions of coronal models and scale-invariant jet models for the origin of radio emission in radio-quiet AGNs, and find general consistency with both models. However, we find that the L {sub R}/ L {sub X} relation does not distinguish between star formation and non-relativistic AGN-driven outflows as the origin of radio emission in radio-quiet AGNs. Finally, we examine where objects with different radio morphologies fall in relation to the main sequence (MS) of star formation, and conclude that those AGNs that fall below the MS, as X-ray selected AGNs have been found to do, have core-dominated or jet-like 22 GHz morphologies.

  5. Pragmatic Information as a Unifying Biological Concept

    Directory of Open Access Journals (Sweden)

    Reza Maleeh

    2014-09-01

    Full Text Available This paper aims to introduce a developed reading of Roederer’s interpretation of pragmatic information as a good candidate for a Unifying Information Concept required for an as-yet-unavailable Science of Information. According to pragmatic information, information and information processing are exclusive attributes of biological systems related to the very definition of life. I will apply the notion to give new accounts in the following areas: (1 quantum interpretation: based on a modified version of David Bohm’s interpretation of quantum mechanics, I propose an ontological, information-based interpretation of quantum mechanics which, unlike Roederer’s interpretation, satisfies all conditions of pragmatic information; (2 artificial intelligence: the notion successfully distinguishes natural living systems from artifacts and natural non-living systems, providing a context to pose an information-based argument against the thesis of Strong Artificial Intelligence; (3 phenomenal consciousness: I will use pragmatic information to modify and update Chalmers’s Double-aspect Theory of Information to be explanatorily more powerful regarding the physical aspect of his theory; (4 causation: based on pragmatic information, I pose a new account of causation which differentiates causation in biology from causation in natural abiotic world.

  6. Unified creep-plasticity model for halite

    International Nuclear Information System (INIS)

    Krieg, R.D.

    1980-11-01

    There are two national energy programs which are considering caverns in geological salt (NaCl) as a storage repository. One is the disposal of nuclear wastes and the other is the storage of oil. Both short-time and long-time structural deformations and stresses must be predictable for these applications. At 300K, the nominal initial temperature for both applications, the salt is at 0.28 of the melting temperature and exhibits a significant time dependent behavior. A constitutive model has been developed which describes the behavior observed in an extensive set of triaxial creep tests. Analysis of these tests showed that a single deformation mechanism seems to be operative over the stress and temperature range of interest so that the secondary creep data can be represented by a power of the stress over the entire test range. This simple behavior allowed a new unified creep-plasticity model to be applied with some confidence. The resulting model recognizes no inherent difference between plastic and creep strains yet models the total inelastic strain reasonably well including primary and secondary creep and reverse loadings. A multiaxial formulation is applied with a back stress. A Bauschinger effect is exhibited as a consequence and is present regardless of the time scale over which the loading is applied. The model would be interpreted as kinematic hardening in the sense of classical plasticity. Comparisons are made between test data and model behavior

  7. Randomized central limit theorems: A unified theory.

    Science.gov (United States)

    Eliazar, Iddo; Klafter, Joseph

    2010-08-01

    The central limit theorems (CLTs) characterize the macroscopic statistical behavior of large ensembles of independent and identically distributed random variables. The CLTs assert that the universal probability laws governing ensembles' aggregate statistics are either Gaussian or Lévy, and that the universal probability laws governing ensembles' extreme statistics are Fréchet, Weibull, or Gumbel. The scaling schemes underlying the CLTs are deterministic-scaling all ensemble components by a common deterministic scale. However, there are "random environment" settings in which the underlying scaling schemes are stochastic-scaling the ensemble components by different random scales. Examples of such settings include Holtsmark's law for gravitational fields and the Stretched Exponential law for relaxation times. In this paper we establish a unified theory of randomized central limit theorems (RCLTs)-in which the deterministic CLT scaling schemes are replaced with stochastic scaling schemes-and present "randomized counterparts" to the classic CLTs. The RCLT scaling schemes are shown to be governed by Poisson processes with power-law statistics, and the RCLTs are shown to universally yield the Lévy, Fréchet, and Weibull probability laws.

  8. Argumentation and Inference: A Unified Approach

    Directory of Open Access Journals (Sweden)

    Christophe Fouqueré

    2013-12-01

    Full Text Available We propose in this paper to use Ludics as a unified framework for the analysis of dialogue and the reasoning system. Not only is Ludics a logical theory, but it may also be built by means of concepts of game theory. We first present the main concepts of Ludics. A design is an abstraction and a generalization of the concept of proof. Interaction between designs is equivalent to cut elimination or modus ponens in logical theories. It appears to be a natural means for representing dialogues and also for reasoning. A design is a set of sequences of alternate actions, similar to a move in game theory. We apply Ludics to argumentative dialogues. We discuss how to model the speech acts of argumentative dialogues in terms of dialogue acts. A dialogue act is given by a Ludics action together with the expression that reveals the action in a turn of speech. We show also how arguments may be stored in a commitment state used for reasoning. Finally we revisit an example of juridical dialogue that has been analyzed by Prakken in a different framework.

  9. Unifying Theories of Psychedelic Drug Effects

    Directory of Open Access Journals (Sweden)

    Link R. Swanson

    2018-03-01

    Full Text Available How do psychedelic drugs produce their characteristic range of acute effects in perception, emotion, cognition, and sense of self? How do these effects relate to the clinical efficacy of psychedelic-assisted therapies? Efforts to understand psychedelic phenomena date back more than a century in Western science. In this article I review theories of psychedelic drug effects and highlight key concepts which have endured over the last 125 years of psychedelic science. First, I describe the subjective phenomenology of acute psychedelic effects using the best available data. Next, I review late 19th-century and early 20th-century theories—model psychoses theory, filtration theory, and psychoanalytic theory—and highlight their shared features. I then briefly review recent findings on the neuropharmacology and neurophysiology of psychedelic drugs in humans. Finally, I describe recent theories of psychedelic drug effects which leverage 21st-century cognitive neuroscience frameworks—entropic brain theory, integrated information theory, and predictive processing—and point out key shared features that link back to earlier theories. I identify an abstract principle which cuts across many theories past and present: psychedelic drugs perturb universal brain processes that normally serve to constrain neural systems central to perception, emotion, cognition, and sense of self. I conclude that making an explicit effort to investigate the principles and mechanisms of psychedelic drug effects is a uniquely powerful way to iteratively develop and test unifying theories of brain function.

  10. Texture Repairing by Unified Low Rank Optimization

    Institute of Scientific and Technical Information of China (English)

    Xiao Liang; Xiang Ren; Zhengdong Zhang; Yi Ma

    2016-01-01

    In this paper, we show how to harness both low-rank and sparse structures in regular or near-regular textures for image completion. Our method is based on a unified formulation for both random and contiguous corruption. In addition to the low rank property of texture, the algorithm also uses the sparse assumption of the natural image: because the natural image is piecewise smooth, it is sparse in certain transformed domain (such as Fourier or wavelet transform). We combine low-rank and sparsity properties of the texture image together in the proposed algorithm. Our algorithm based on convex optimization can automatically and correctly repair the global structure of a corrupted texture, even without precise information about the regions to be completed. This algorithm integrates texture rectification and repairing into one optimization problem. Through extensive simulations, we show our method can complete and repair textures corrupted by errors with both random and contiguous supports better than existing low-rank matrix recovery methods. Our method demonstrates significant advantage over local patch based texture synthesis techniques in dealing with large corruption, non-uniform texture, and large perspective deformation.

  11. Constraints on grand unified superstring theories

    International Nuclear Information System (INIS)

    Ellis, J.; Lopez, J.L.; Nanopoulos, D.V.; Houston Advanced Research Center

    1990-01-01

    We evaluate some constraints on the construction of grand unified superstring theories (GUSTs) using higher level Kac-Moody algebras on the world-sheet. In the most general formulation of the heterotic string in four dimensions, an analysis of the basic GUST model-building constraints, including a realistic hidden gauge group, reveals that there are no E 6 models and any SO(10) models can only exist at level-5. Also, any such SU(5) models can exist only for levels 4≤k≤19. These SO(10) and SU(5) models risk having many large, massless, phenomenologically troublesome representations. We also show that with a suitable hidden sector gauge group, it is possible to avoid free light fractionally charged particles, which are endemic to string derived models. We list all such groups and their representations for the flipped SU(5)xU(1) model. We conclude that a sufficiently binding hidden sector gauge group becomes a basic model-building constraint. (orig.)

  12. A Unified Model for Tidal Disruption Events

    Science.gov (United States)

    Dai, Lixin; McKinney, Jonathan C.; Roth, Nathaniel; Ramirez-Ruiz, Enrico; Miller, M. Coleman

    2018-06-01

    In the past few years wide-field optical and UV transient surveys and X-ray telescopes have allowed us to identify a few dozen candidate tidal disruption events (TDEs). While in theory the physical processes in TDEs are ubiquitous, a few distinct classes of TDEs have been observed. Some TDEs radiate mainly in NUV/optical, while others produce prominent X-rays. Moreover, relativistic jets have been observed in only a handful of TDEs. This diversity might be related to the details of the super-Eddington accretion and emission physics relevant to TDE disks. In this Letter, we utilize novel three-dimensional general relativistic radiation magnetohydrodynamics simulations to study the super-Eddington compact disk phase expected in TDEs. Consistent with previous studies, geometrically thick disks, wide-angle optically thick fast outflows, and relativistic jets are produced. The outflow density and velocity depend sensitively on the inclination angle, and hence so does the reprocessing of emission produced from the inner disk. We then use Monte Carlo radiative transfer to calculate the reprocessed spectra and find that that the observed ratio of optical to X-ray fluxes increases with increasing inclination angle. This naturally leads to a unified model for different classes of TDEs in which the spectral properties of the TDE depend mainly on the viewing angle of the observer with respect to the orientation of the disk.

  13. A unified grand tour of theoretical physics

    CERN Document Server

    Griffiths, J

    2002-01-01

    Anyone offering a grand tour is faced with several options. Should they concentrate on what may be considered to be essential features, or should they attempt to present a brief glimpse of almost everything? The present offering is a compromise between these two extremes. The area considered - theoretical physics - is now such a vast subject that some kind of compromise is essential. Indeed, the field is now so wide that few could even attempt to review it in a single-authored work. My task here is to assess how well this book has succeeded in its main aim of providing a unified (though introductory) tour of this subject. Constrained within a single volume, this is clearly not an updated Landau-Lifschitz. It cannot be expected to take any particular topic to the level of recent research. Nevertheless, it does seem to cover the broad range of essential topics which now constitute the subject. It starts (most appropriately in my opinion) with geometry. It then covers classical physics, general relativity and qu...

  14. Unifying Theories of Psychedelic Drug Effects

    Science.gov (United States)

    Swanson, Link R.

    2018-01-01

    How do psychedelic drugs produce their characteristic range of acute effects in perception, emotion, cognition, and sense of self? How do these effects relate to the clinical efficacy of psychedelic-assisted therapies? Efforts to understand psychedelic phenomena date back more than a century in Western science. In this article I review theories of psychedelic drug effects and highlight key concepts which have endured over the last 125 years of psychedelic science. First, I describe the subjective phenomenology of acute psychedelic effects using the best available data. Next, I review late 19th-century and early 20th-century theories—model psychoses theory, filtration theory, and psychoanalytic theory—and highlight their shared features. I then briefly review recent findings on the neuropharmacology and neurophysiology of psychedelic drugs in humans. Finally, I describe recent theories of psychedelic drug effects which leverage 21st-century cognitive neuroscience frameworks—entropic brain theory, integrated information theory, and predictive processing—and point out key shared features that link back to earlier theories. I identify an abstract principle which cuts across many theories past and present: psychedelic drugs perturb universal brain processes that normally serve to constrain neural systems central to perception, emotion, cognition, and sense of self. I conclude that making an explicit effort to investigate the principles and mechanisms of psychedelic drug effects is a uniquely powerful way to iteratively develop and test unifying theories of brain function. PMID:29568270

  15. X-ray View of Four High-Luminosity Swift-BAT AGN: Unveiling Obscuration and Reflection with Suzaku

    Science.gov (United States)

    Fiorettil, V.; Angelini, L.; Mushotzky, R. F.; Koss, M.; Malaguti, G.

    2013-01-01

    Aims. A complete census of obscured Active Galactic Nuclei (AGN) is necessary to reveal the history of the super massive black hole (SMBH) growth and galaxy evolution in the Universe given the complex feedback processes and the fact that much of this growth occurs in an obscured phase. In this context, hard X-ray surveys and dedicated follow-up observations represent a unique tool for selecting highly absorbed AGN and for characterizing the obscuring matter surrounding the SMBH. Here we focus on the absorption and reflection occurring in highly luminous, quasar-like AGN, to study the relation between the geometry of the absorbing matter and the AGN nature (e.g. X-ray, optical, and radio properties), and to help to determine the column density dependency on the AGN luminosity. Methods. The Swift/BAT nine-month survey observed 153 AGN, all with ultra-hard X-ray BAT fluxes in excess of 10(exp -11) erg per square centimeter and an average redshift of 0.03. Among them, four of the most luminous BAT AGN (44.73 less than LogLBAT less than 45.31) were selected as targets of Suzaku follow-up observations: J2246.0+3941 (3C 452), J0407.4+0339 (3C 105), J0318.7+6828, and J0918.5+0425. The column density, scattered/reflected emission, the properties of the Fe K line, and a possible variability are fully analyzed. For the latter, the spectral properties from Chandra, XMM-Newton and Swift/XRT public observations were compared with the present Suzaku analysis, adding an original spectral analysis when non was available from the literature. Results. Of our sample, 3C 452 is the only certain Compton-thick AGN candidate because of i) the high absorption (N(sub H) approximately 4 × 10(exp 23) per square centimeter) and strong Compton reflection; ii) the lack of variability; iii) the "buried" nature, i.e. the low scattering fraction (less than 0.5%) and the extremely low relative [OIII] luminosity. In contrast 3C 105 is not reflection-dominated, despite the comparable column density

  16. THE ROLE OF STAR FORMATION AND AN AGN IN DUST HEATING OF z = 0.3–2.8 GALAXIES. I. EVOLUTION WITH REDSHIFT AND LUMINOSITY

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, Allison; Pope, Alexandra [Department of Astronomy, University of Massachusetts, Amherst, MA 01002 (United States); Sajina, Anna; Roebuck, Eric [Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Yan, Lin [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Armus, Lee [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Díaz-Santos, Tanio [Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago (Chile); Stierwalt, Sabrina, E-mail: kirkpatr@astro.umass.edu [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)

    2015-11-20

    We characterize infrared spectral energy distributions of 343 (ultra)luminous infrared galaxies from z = 0.3–2.8. We diagnose the presence of an active galactic nucleus (AGN) by decomposing individual Spitzer mid-IR spectroscopy into emission from star formation and an AGN-powered continuum; we classify sources as star-forming galaxies (SFGs), AGNs, or composites. Composites comprise 30% of our sample and are prevalent at faint and bright S{sub 24}, making them an important source of IR AGN emission. We combine spectroscopy with multiwavelength photometry, including Herschel imaging, to create three libraries of publicly available templates (2–1000 μm). We fit the far-IR emission using a two-temperature modified blackbody to measure cold and warm dust temperatures (T{sub c} and T{sub w}). We find that T{sub c} does not depend on mid-IR classification, while T{sub w} shows a notable increase as the AGN grows more luminous. We measure a quadratic relationship between mid-IR AGN emission and total AGN contribution to L{sub IR}. AGNs, composites, and SFGs separate in S{sub 8}/S{sub 3.6} and S{sub 250}/S{sub 24}, providing a useful diagnostic for estimating relative amounts of these sources. We estimate that >40% of IR-selected samples host an AGN, even at faint selection thresholds (S{sub 24} > 100 μJy). Our decomposition technique and color diagnostics are relevant given upcoming observations with the James Webb Space Telescope.

  17. Superluminous Transients at AGN Centers from Interaction between Black Hole Disk Winds and Broad-line Region Clouds

    Energy Technology Data Exchange (ETDEWEB)

    Moriya, Takashi J.; Tanaka, Masaomi; Ohsuga, Ken [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Morokuma, Tomoki, E-mail: takashi.moriya@nao.ac.jp [Institute of Astronomy, Graduate School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan)

    2017-07-10

    We propose that superluminous transients that appear at central regions of active galactic nuclei (AGNs) such as CSS100217:102913+404220 (CSS100217) and PS16dtm, which reach near- or super-Eddington luminosities of the central black holes, are powered by the interaction between accretion-disk winds and clouds in broad-line regions (BLRs) surrounding them. If the disk luminosity temporarily increases by, e.g., limit–cycle oscillations, leading to a powerful radiatively driven wind, strong shock waves propagate in the BLR. Because the dense clouds in the AGN BLRs typically have similar densities to those found in SNe IIn, strong radiative shocks emerge and efficiently convert the ejecta kinetic energy to radiation. As a result, transients similar to SNe IIn can be observed at AGN central regions. Since a typical black hole disk-wind velocity is ≃0.1 c , where c is the speed of light, the ejecta kinetic energy is expected to be ≃10{sup 52} erg when ≃1 M {sub ⊙} is ejected. This kinetic energy is transformed to radiation energy in a timescale for the wind to sweep up a similar mass to itself in the BLR, which is a few hundred days. Therefore, both luminosities (∼10{sup 44} erg s{sup −1}) and timescales (∼100 days) of the superluminous transients from AGN central regions match those expected in our interaction model. If CSS100217 and PS16dtm are related to the AGN activities triggered by limit–cycle oscillations, they become bright again in coming years or decades.

  18. Short time-scale optical variability properties of the largest AGN sample observed with Kepler/K2

    Science.gov (United States)

    Aranzana, E.; Körding, E.; Uttley, P.; Scaringi, S.; Bloemen, S.

    2018-05-01

    We present the first short time-scale (˜hours to days) optical variability study of a large sample of active galactic nuclei (AGNs) observed with the Kepler/K2 mission. The sample contains 252 AGN observed over four campaigns with ˜30 min cadence selected from the Million Quasar Catalogue with R magnitude <19. We performed time series analysis to determine their variability properties by means of the power spectral densities (PSDs) and applied Monte Carlo techniques to find the best model parameters that fit the observed power spectra. A power-law model is sufficient to describe all the PSDs of our sample. A variety of power-law slopes were found indicating that there is not a universal slope for all AGNs. We find that the rest-frame amplitude variability in the frequency range of 6 × 10-6-10-4 Hz varies from 1to10 per cent with an average of 1.7 per cent. We explore correlations between the variability amplitude and key parameters of the AGN, finding a significant correlation of rest-frame short-term variability amplitude with redshift. We attribute this effect to the known `bluer when brighter' variability of quasars combined with the fixed bandpass of Kepler data. This study also enables us to distinguish between Seyferts and blazars and confirm AGN candidates. For our study, we have compared results obtained from light curves extracted using different aperture sizes and with and without detrending. We find that limited detrending of the optimal photometric precision light curve is the best approach, although some systematic effects still remain present.

  19. SPIDERS: selection of spectroscopic targets using AGN candidates detected in all-sky X-ray surveys

    Science.gov (United States)

    Dwelly, T.; Salvato, M.; Merloni, A.; Brusa, M.; Buchner, J.; Anderson, S. F.; Boller, Th.; Brandt, W. N.; Budavári, T.; Clerc, N.; Coffey, D.; Del Moro, A.; Georgakakis, A.; Green, P. J.; Jin, C.; Menzel, M.-L.; Myers, A. D.; Nandra, K.; Nichol, R. C.; Ridl, J.; Schwope, A. D.; Simm, T.

    2017-07-01

    SPIDERS (SPectroscopic IDentification of eROSITA Sources) is a Sloan Digital Sky Survey IV (SDSS-IV) survey running in parallel to the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) cosmology project. SPIDERS will obtain optical spectroscopy for large numbers of X-ray-selected active galactic nuclei (AGN) and galaxy cluster members detected in wide-area eROSITA, XMM-Newton and ROSAT surveys. We describe the methods used to choose spectroscopic targets for two sub-programmes of SPIDERS X-ray selected AGN candidates detected in the ROSAT All Sky and the XMM-Newton Slew surveys. We have exploited a Bayesian cross-matching algorithm, guided by priors based on mid-IR colour-magnitude information from the Wide-field Infrared Survey Explorer survey, to select the most probable optical counterpart to each X-ray detection. We empirically demonstrate the high fidelity of our counterpart selection method using a reference sample of bright well-localized X-ray sources collated from XMM-Newton, Chandra and Swift-XRT serendipitous catalogues, and also by examining blank-sky locations. We describe the down-selection steps which resulted in the final set of SPIDERS-AGN targets put forward for spectroscopy within the eBOSS/TDSS/SPIDERS survey, and present catalogues of these targets. We also present catalogues of ˜12 000 ROSAT and ˜1500 XMM-Newton Slew survey sources that have existing optical spectroscopy from SDSS-DR12, including the results of our visual inspections. On completion of the SPIDERS programme, we expect to have collected homogeneous spectroscopic redshift information over a footprint of ˜7500 deg2 for >85 per cent of the ROSAT and XMM-Newton Slew survey sources having optical counterparts in the magnitude range 17 < r < 22.5, producing a large and highly complete sample of bright X-ray-selected AGN suitable for statistical studies of AGN evolution and clustering.

  20. The role of AGN feedback in galaxy evolution at high-redshift

    International Nuclear Information System (INIS)

    Collet, Cedric

    2014-01-01

    There is growing evidence that supermassive black holes may play a crucial role for galaxy evolution, in particular during the formation of massive galaxies at high redshift (z ≅ 2 - 3). Our work focuses on quantifying the effects of jets of radiogalaxies and of large bolometric luminosities of quasars on the interstellar gas in their host galaxies. To this end, we studied the kinematics of the ionized gas in 12 moderately powerful radio galaxies and 11 quasars (6 radio-loud and 5 radio-quiet) at high redshifts with rest-frame optical imaging spectroscopy obtained at the VLT with SINFONI. We searched for outflows and other signatures of feedback from the supermassive black holes in the centers of these galaxies to evaluate if the AGN may plausibly quench star formation. In our sample of moderately powerful radiogalaxies, we observe velocity dispersions nearly as large as those observed in the most powerful ones (with FWHM ≅ 1000 km/s), but the quantity of ionized gas is decreased by one order of magnitude (M-ion gas ≅ 10"8 - 10"9 M-sun) and velocity gradients tend to be less dramatic (Δv ≤ 400 km/s), when they are observed. In our sample of quasars, we had to carefully subtract the broad spectral component of emission lines to have access to its narrow, and spatially extended, component. We detect truly extended emission line regions in 4/6 sources of our radio-loud sub-sample and in 1/5 source of our radio-quiet sub-sample. We estimate that masses of ionized gas in these sources are smaller than in our sample of high-redshift radiogalaxies (with Mion gas ≅ 10"7 - 10"8 Msun) and kinematics tend to be more quiescent, akin to what is observed in local quasars. Finally, detailed observations of two outliers among our sample of high-redshift radiogalaxies revealed that one of them is closely surrounded by 14 companions galaxies, hence lying in an over density. We therefore interpret the presence and morphology of ionized gas around these galaxies as evidence