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  1. THE LOW-REDSHIFT CARNEGIE SUPERNOVA PROJECT

    Directory of Open Access Journals (Sweden)

    G. Folatelli

    2009-01-01

    Full Text Available We present the low-redshift Carnegie Supernova Project (CSP, an undergoing program to follow up about 250 nearby supernovae (SNe of all types. We brie y describe the observations which yield well-sampled, highly precise optical and near-infrared light curves in a well-understood photometric system, complemented with optical spectroscopy. As one of the main goals of the CSP, we preliminarily present the rst Hubble diagram using a sample of 30 Type-Ia SNe (SNe Ia.

  2. Spectroscopy of Type Ia Supernovae by the Carnegie Supernova Project

    CERN Document Server

    Folatelli, Gastón; Phillips, Mark M; Hsiao, Eric; Campillay, Abdo; Contreras, Carlos; Castellón, Sergio; Hamuy, Mario; Krzeminski, Wojtek; Roth, Miguel; Stritzinger, Maximilian; Burns, Christopher R; Freedman, Wendy L; Madore, Barry F; Murphy, David; Persson, S E; Prieto, José L; Suntzeff, Nicholas B; Krisciunas, Kevin; Anderson, Joseph P; Förster, Francisco; Maza, José; Pignata, Giuliano; Rojas, P Andrea; Boldt, Luis; Salgado, Francisco; Wyatt, Pamela; E., Felipe Olivares; Gal-Yam, Avishay; Sako, Masao

    2013-01-01

    This is the first release of optical spectroscopic data of low-redshift Type Ia supernovae (SNe Ia) by the Carnegie Supernova Project including 604 previously unpublished spectra of 93 SNe Ia. The observations cover a range of phases from 12 days before to over 150 days after the time of B-band maximum light. With the addition of 228 near-maximum spectra from the literature we study the diversity among SNe Ia in a quantitative manner. For that purpose, spectroscopic parameters are employed such as expansion velocities from spectral line blueshifts, and pseudo-equivalent widths (pW). The values of those parameters at maximum light are obtained for 78 objects, thus providing a characterization of SNe Ia that may help to improve our understanding of the properties of the exploding systems and the thermonuclear flame propagation. Two objects, namely SNe 2005M and 2006is, stand out from the sample by showing peculiar Si II and S II velocities but otherwise standard velocities for the rest of the ions. We further s...

  3. Carnegie Supernova Project: Observations of Type IIn Supernovae

    CERN Document Server

    Taddia, F; Sollerman, J; Phillips, M M; Anderson, J P; Boldt, L; Campillay, A; Castellón, S; Contreras, C; Folatelli, G; Hamuy, M; Heinrich-Josties, E; Krzeminski, W; Morrell, N; Burns, C R; Freedman, W L; Madore, B F; Persson, S E; Suntzeff, N B

    2013-01-01

    The observational diversity displayed by various Type IIn supernovae (SNe IIn) is explored and quantified. In doing so a more coherent picture ascribing the variety of observed SNe IIn types to particular progenitor scenarios is sought. Carnegie Supernova Project (CSP) optical and near-infrared light curves and visual-wavelength spectroscopy of the Type IIn SNe 2005kj, 2006aa, 2006bo, 2006qq and 2008fq are presented. Combined with previously published observations of the Type IIn SNe 2005ip and 2006jd (Stritzinger et al. 2012), the full CSP sample is used to derive physical parameters which describe the nature of the interaction between the expanding SN ejecta and the circum-stellar material (CSM). For each SN of our sample we find counterparts, identifying objects similar to SNe 1994W (SN 2006bo), 1998S (SN 2008fq) and 1988Z (SN 2006qq). We present the unprecedented initial u-band plateau of SN 2006aa, and its peculiar late-time luminosity and temperature evolution. For each SN, assuming the CSM was formed b...

  4. The Carnegie Supernova Project: Intrinsic Colors of Type Ia Supernovae

    CERN Document Server

    Burns, Christopher R; Phillips, M M; Hsiao, E Y; Contreras, Carlos; Persson, S E; Folatelli, Gaston; Boldt, Luis; Campillay, Abdo; Catellón, Sergio; Freedman, Wendy L; Madore, Barry F; Morrell, Nidia; Salgado, Francisco; Suntzeff, Nicholas B

    2014-01-01

    We present an updated analysis of the intrinsic colors of SNe Ia using the latest data release of the Carnegie Supernova Project. We introduce a new light-curve parameter very similar to stretch that is better suited for fast-declining events, and find that these peculiar types can be seen as extensions to the population of "normal" SNe Ia. With a larger number of objects, an updated fit to the Lira relation is presented along with evidence for a dependence on the late-time slope of the B-V color-curves with stretch and color. Using the full wavelength range from u to H band, we place constraints on the reddening law for the sample as a whole and also for individual events/hosts based solely on the observed colors. The photometric data continue to favor low values of Rv, though with large variations from event to event, indicating an intrinsic distribution. We confirm the findings of other groups that there appears to be a correlation between the derived reddening law, Rv, and the color excess, E(B-V), such t...

  5. See Change: the Supernova Sample from the Supernova Cosmology Project High Redshift Cluster Supernova Survey

    Science.gov (United States)

    Hayden, Brian; Perlmutter, Saul; Boone, Kyle; Nordin, Jakob; Rubin, David; Lidman, Chris; Deustua, Susana E.; Fruchter, Andrew S.; Aldering, Greg Scott; Brodwin, Mark; Cunha, Carlos E.; Eisenhardt, Peter R.; Gonzalez, Anthony H.; Jee, James; Hildebrandt, Hendrik; Hoekstra, Henk; Santos, Joana; Stanford, S. Adam; Stern, Daniel; Fassbender, Rene; Richard, Johan; Rosati, Piero; Wechsler, Risa H.; Muzzin, Adam; Willis, Jon; Boehringer, Hans; Gladders, Michael; Goobar, Ariel; Amanullah, Rahman; Hook, Isobel; Huterer, Dragan; Huang, Xiaosheng; Kim, Alex G.; Kowalski, Marek; Linder, Eric; Pain, Reynald; Saunders, Clare; Suzuki, Nao; Barbary, Kyle H.; Rykoff, Eli S.; Meyers, Joshua; Spadafora, Anthony L.; Sofiatti, Caroline; Wilson, Gillian; Rozo, Eduardo; Hilton, Matt; Ruiz-Lapuente, Pilar; Luther, Kyle; Yen, Mike; Fagrelius, Parker; Dixon, Samantha; Williams, Steven

    2017-01-01

    The Supernova Cosmology Project has finished executing a large (174 orbits, cycles 22-23) Hubble Space Telescope program, which has measured ~30 type Ia Supernovae above z~1 in the highest-redshift, most massive galaxy clusters known to date. Our SN Ia sample closely matches our pre-survey predictions; this sample will improve the constraint by a factor of 3 on the Dark Energy equation of state above z~1, allowing an unprecedented probe of Dark Energy time variation. When combined with the improved cluster mass calibration from gravitational lensing provided by the deep WFC3-IR observations of the clusters, See Change will triple the Dark Energy Task Force Figure of Merit. With the primary observing campaign completed, we present the preliminary supernova sample and our path forward to the supernova cosmology results. We also compare the number of SNe Ia discovered in each cluster with our pre-survey expectations based on cluster mass and SFR estimates. Our extensive HST and ground-based campaign has already produced unique results; we have confirmed several of the highest redshift cluster members known to date, confirmed the redshift of one of the most massive galaxy clusters at z~1.2 expected across the entire sky, and characterized one of the most extreme starburst environments yet known in a z~1.7 cluster. We have also discovered a lensed SN Ia at z=2.22 magnified by a factor of ~2.7, which is the highest spectroscopic redshift SN Ia currently known.

  6. The Carnegie Supernova Project: The Low-Redshift Survey

    CERN Document Server

    Hamuy, M; Morrell, N I; Phillips, M M; Suntzeff, N B; Persson, S E; Roth, M; González, S; Krzeminski, W; Contreras, C S; Freedman, W L; Murphy, D C; Madore, B F; Wyatt, P; Maza, J; Filippenko, A V; Li, W; Pinto, P A; Hamuy, Mario; Folatelli, Gast\\'on; Morrell, Nidia I.; Phillips, Mark M.; Suntzeff, Nicholas B.; Roth, Miguel; Gonzalez, Sergio; Krzeminski, Wojtek; Contreras, Carlos; Freedman, Wendy L.; Madore, Barry F.; Maza, Jos\\'{e}; Filippenko, Alexei V.; Li, Weidong

    2005-01-01

    Supernovae are essential to understanding the chemical evolution of the Universe. Type Ia supernovae also provide the most powerful observational tool currently available for studying the expansion history of the Universe and the nature of dark energy. Our basic knowledge of supernovae comes from the study of their photometric and spectroscopic properties. However, the presently available data sets of optical and near-infrared light curves of supernovae are rather small and/or heterogeneous, and employ photometric systems that are poorly characterized. Similarly, there are relatively few supernovae whose spectral evolution has been well sampled, both in wavelength and phase, with precise spectrophotometric observations. The low-redshift portion of the Carnegie Supernova Project (CSP) seeks to remedy this situation by providing photometry and spectrophotometry of a large sample of supernovae taken on telescope/filter/detector systems that are well understood and well characterized. During a five-year program w...

  7. First Results from the La Silla-QUEST Supernova Survey and the Carnegie Supernova Project

    CERN Document Server

    Walker, E S; Campillay, A; Citrenbaum, C; Contreras, C; Ellman, N; Feindt, U; Gonzalez, C; Graham, M L; Hadjiyska, E; Hsiao, E Y; Krisciunas, K; McKinnon, R; Ment, K; Morrell, N; Nugent, P; Phillips, M; Rabinowitz, D; Rostami, S; Seron, J; Stritzinger, M; Sullivan, M; Tucker, B E

    2016-01-01

    The LaSilla/QUEST Variability Survey (LSQ) and the Carnegie Supernova Project (CSP II) are collaborating to discover and obtain photometric light curves for a large sample of low redshift (z < 0.1) Type Ia supernovae. The supernovae are discovered in the LSQ survey using the 1 m ESO Schmidt telescope at the La Silla Observatory with the 10 square degree QUEST camera. The follow-up photometric observations are carried out using the 1 m Swope telescope and the 2.5 m du Pont telescopes at the Las Campanas Observatory. This paper describes the survey, discusses the methods of analyzing the data and presents the light curves for the first 31 Type Ia supernovae obtained in the survey. The SALT 2.4 supernova light curve fitter was used to analyze the photometric data, and the Hubble diagram for this first sample is presented. The measurement errors for these supernovae averaged 4%, and their intrinsic spread was 14%.

  8. 77 FR 58181 - Power Resources, Inc., Smith Ranch Highland Uranium Project; License Renewal Request, Opportunity...

    Science.gov (United States)

    2012-09-19

    ... COMMISSION Power Resources, Inc., Smith Ranch Highland Uranium Project; License Renewal Request, Opportunity...-415- 4737, or by email to pdr.resource@nrc.gov . The ADAMS accession number for each document... is referenced. The Smith Ranch Highland Uranium Project license renewal request is...

  9. Exploring Supernova Remnants with the SPIES Project

    Science.gov (United States)

    Frank, Kari A.; Burrows, David N.; Dwarkadas, Vikram

    2017-01-01

    X-ray observations provide a key window into supernova remnants, providing measurements of a plethora of physical properties that are critical for understanding SNRs, their environments, their progenitors, and the SNe that created them. However, characterizing the entire volume of shocked plasma in a SNR is difficult, due to their complicated three dimensional morphologies and spectra. The SPIES project aims to address this problem by applying a novel X-ray analysis method, Smoothed Particle Inference (SPI), to XMM observations of 12 SNRs. SPI is a Bayesian modeling process that fits a population of gas blobs ("smoothed particles") such that their superposed emission reproduces the observed spatial and spectral distribution of photons. Emission-weighted distributions and maps of plasma properties, such as abundances and temperatures, are then extracted from the properties of the individual blobs. Additionally, because the collection of blobs is a multi-dimensional representation of the shocked plasma, we can carry out a more detailed exploration of plasma properties by extracting any subset of the blobs (e.g. those with the highest temperatures) and investigating its properties (e.g. map the abundances). Here we present preliminary results from SPI analyses of the first 6 remnants in the SPIES project.

  10. Discovery and Classification of Five New Supernovae by the Palomar Transient Factory

    Science.gov (United States)

    Arcavi, I.; Horesh, A.; Sesar, B.; Sullivan, M.; Maguire, K.; Ben-Ami, S.; Sternberg, A.; Green, Y.; Gal-Yam, A.; Kulkarni, S. R.; Quimby, R.; Kasliwal, M. M.; Ofek, E. O.; Nugent, P. E.; Howell, D. A.; Bloom, J.; Cooke, J.; Cenko, S. B.; Law, N.

    2010-12-01

    We report the discovery and spectroscopic classification of five new supernovae from PTF (ATel #1964; http://www.astro.caltech.edu/ptf). The supernovae were discovered by Oarical, an autonomous software framework of the PTF collaboration and by the users of Galaxy Zoo Supernovae, a citizen science project (http://supernova.galaxyzoo.org; Smith et al. 2010, arXiv 1011.2199), based on observations made with the Palomar 48-inch Oschin Schmidt telescope.

  11. The Carnegie Supernova Project: Second Photometry Data Release of Low-Redshift Type Ia Supernovae

    CERN Document Server

    Stritzinger, Maximilian; S., Luis Boldt; Burns, Chris; Campillay, Abdo; Contreras, Carlos; Gonzalez, Sergio; Folatelli, Gaston; Morrell, Nidia; Krzeminski, Wojtek; Roth, Miguel; Salgado, Francisco; Depoy, Darren L; Hamuy, Mario; Freedman, Wendy L; Madore, Barry; Marshall, Jennifer L; Persson, Sven E; Rheault, Jean-Philippe; Suntzeff, Nicholas; Villanueva, Steven; Li, Weidong; Filippenko, Alexei V

    2011-01-01

    The Carnegie Supernova Project (CSP) was a five-year observational survey conducted at Las Campanas Observatory that obtained, among other things, high-quality light curves of ~100 low-redshift Type Ia supernovae (SNe Ia). Presented here is the second data release of nearby SN Ia photometry consisting of 50 objects, with a subset of 45 having near-infrared follow-up observations. Thirty-three objects have optical pre-maximum coverage with a subset of 15 beginning at least 5 days before maximum light. In the near-infrared, 27 objects have coverage beginning before the epoch of B-band maximum, with a subset of 13 beginning at least 5 days before maximum. In addition, we present results of a photometric calibration program to measure the CSP optical (uBgVri)bandpasses with an accuracy of ~1%. Finally, we report the discovery of a second SN Ia, SN 2006ot, similar in its characteristics to the peculiar SN 2006bt.

  12. Supernovae

    Science.gov (United States)

    March, Marisa

    2014-03-01

    We live in a Universe that is getting bigger faster. This astonishing discovery of Universal acceleration was made in the late 1990s by two teams who made observations of a special type of exploded star known as a `Supernova Type Ia'. (SNeIa) Since the discovery of the accelerating Universe, one of the biggest questions in modern cosmology has been to determine the cause of that acceleration - the answer to this question will have far reaching implications for our theories of cosmology and fundamental physics more broadly. The two main competing explanations for this apparent late time acceleration of the Universe are modified gravity and dark energy. The Dark Energy Survey (DES) has been designed and commissioned to find to find answers to these questions about the nature of dark energy and modified gravity. The new 570 megapixel Dark Energy Camera is currently operating with the Cerro-Tololo Inter American Observatory's 4m Blanco teleccope, carrying out a systematic search for SNeIa, and mapping out the large scale structure of the Universe by making observations of galaxies. The DES science program program which saw first light in September 2013 will run for five years in total. DES SNeIa data in combination with the other DES observations of large scale structure will enable us to put increasingly accurate constraints on the expansion history of the Universe and will help us distinguish between competing theories of dark energy and modified gravity. As we draw to the close of the first observing season of DES in March 2014, we will report on the current status of the DES supernova survey, presenting first year supernovae data, preliminary results, survey strategy, discovery pipeline, spectroscopic target selection and data quality. This talk will give the first glimpse of the DES SN first year data and initial results as we begin our five year survey in search of dark energy. On behalf of the Dark Energy Survey collaboration.

  13. Observations of Supernova Remnants and Pulsar Wind Nebulae: A VERITAS Key Science Project

    CERN Document Server

    Humensky, Brian

    2009-01-01

    The study of supernova remnants and pulsar wind nebulae was one of the Key Science Projects for the first two years of VERITAS observations. VERITAS is an array of four imaging Cherenkov telescopes located at the Whipple Observatory in southern Arizona. Supernova remnants are widely considered to be the strongest candidate for the source of cosmic rays below the knee at around 10^15 eV. Pulsar wind nebulae are synchrotron nebulae powered by the spin-down of energetic young pulsars, and comprise one of the most populous very-high-energy gamma-ray source classes. This poster will summarize the results of this observation program.

  14. Expectation on Observation of Supernova Remnants with the LHAASO Project

    Science.gov (United States)

    Liu, Ye; Cao, Zhen; Chen, Songzhan; Chen, Yang; Cui, Shuwang; He, Huihai; Huang, Xingtao; Ma, Xinhua; Yuan, Qiang; Zhang, Xiao; LHAASO Collaboration

    2016-07-01

    Supernova remnants (SNRs) are believed to be the most important acceleration sites for cosmic rays (CRs) below ˜1015 eV in the Galaxy. High-energy photons, either directly from the shocks of the SNRs or indirectly from the interaction between SNRs and the nearby clouds, are crucial probes for the CR acceleration. Big progresses on observations of SNRs have been achieved by space- and ground-based γ-ray facilities. However, whether γ-rays come from accelerated hadrons or not, as well as their connection with the CRs observed at Earth, remains in debate. Large High Altitude Air Shower Observatory (LHAASO), a next-generation experiment, is designed to survey the northern part of the very high energy γ-ray sky from ˜0.3 TeV to PeV with the sensitivity of ≲1% of the Crab Nebula flux. In this paper, we indicate that LHAASO will be dedicated to enlarging the γ-ray SNR samples and improving the spectral and morphological measurements. These measurements, especially at energies above 30 TeV, will be important for us to finally understand the CR acceleration in SNRs.

  15. Expectation on Observation of Supernova Remnants with the LHAASO Project

    CERN Document Server

    Liu, Ye; Chen, Songzhan; Chen, Yang; Cui, Shuwang; He, Huihai; Huang, Xingtao; Ma, Xinhua; Yuan, Qiang; Zhang, Xiao

    2016-01-01

    Supernova remnants (SNRs) are believed to be the most important acceleration sites for cosmic rays (CRs) below $\\sim10^{15}$ eV in the Galaxy. High energy photons, either directly from the shocks of the SNRs or indirectly from the interaction between SNRs and the nearby clouds, are crucial probes for the CR acceleration. Big progresses on observations of SNRs have been achieved by space- and ground-based $\\gamma$-ray facilities. However, whether $\\gamma$-rays come from accelerated hadrons or not, as well as their connection with the CRs observed at Earth, remains in debate. Large High Altitude Air Shower Observatory (LHAASO), the next generation experiment, is designed to survey the northern part of the very high energy $\\gamma$-ray sky from $\\sim 0.3$ TeV to PeV with the sensitivity of $\\lesssim1\\%$ of the Crab nebula flux. In this paper, we indicate that LHAASO will be dedicated to enlarging the $\\gamma$-ray SNR samples and improving the spectral and morphological measurements. These measurements, especiall...

  16. The Carnegie Supernova Project: First Near-Infrared Hubble Diagram to z~0.7

    CERN Document Server

    Freedman, Wendy L; Phillips, M M; Wyatt, Pamela; Persson, S E; Madore, Barry F; Contreras, Carlos; Folatelli, Gaston; Gonzalez, E Sergio; Hamuy, Mario; Hsiao, Eric; Kelson, Daniel D; Morrell, Nidia; Murphy, D C; Roth, Miguel; Stritzinger, Maximilian; Sturch, Laura; Suntzeff, Nick B; Astier, P; Balland, C; Bassett, Bruce; Boldt, Luis; Carlberg, R G; Conley, Alexander J; Frieman, Joshua A; Garnavich, Peter M; Guy, J; Hardin, D; Howell, D Andrew; Kessler, Richard; Lampeitl, Hubert; Marriner, John; Pain, R; Perrett, Kathy; Regnault, N; Riess, Adam G; Sako, Masao; Schneider, Donald P; Sullivan, Mark; Wood-Vasey, Michael

    2009-01-01

    The Carnegie Supernova Project (CSP) is designed to measure the luminosity distance for Type Ia supernovae (SNe Ia) as a function of redshift, and to set observational constraints on the dark energy contribution to the total energy content of the Universe. The CSP differs from other projects to date in its goal of providing an I-band {rest-frame} Hubble diagram. Here we present the first results from near-infrared (NIR) observations obtained using the Magellan Baade telescope for SNe Ia with 0.1 < z < 0.7. We combine these results with those from the low-redshift CSP at z <0.1 (Folatelli et al. 2009). We present light curves and an I-band Hubble diagram for this first sample of 35 SNe Ia and we compare these data to 21 new SNe Ia at low redshift. These data support the conclusion that the expansion of the Universe is accelerating. When combined with independent results from baryon acoustic oscillations (Eisenstein et al. 2005), these data yield Omega_m = 0.27 +/- 0.0 (statistical), and Omega_DE = 0.7...

  17. The Carnegie Supernova Project: Light-curve Fitting with SNooPy

    Science.gov (United States)

    Burns, Christopher R.; Stritzinger, Maximilian; Phillips, M. M.; Kattner, ShiAnne; Persson, S. E.; Madore, Barry F.; Freedman, Wendy L.; Boldt, Luis; Campillay, Abdo; Contreras, Carlos; Folatelli, Gaston; Gonzalez, Sergio; Krzeminski, Wojtek; Morrell, Nidia; Salgado, Francisco; Suntzeff, Nicholas B.

    2011-01-01

    In providing an independent measure of the expansion history of the universe, the Carnegie Supernova Project (CSP) has observed 71 high-z Type Ia supernovae (SNe Ia) in the near-infrared bands Y and J. These can be used to construct rest-frame i-band light curves which, when compared to a low-z sample, yield distance moduli that are less sensitive to extinction and/or decline-rate corrections than in the optical. However, working with NIR observed and i-band rest-frame photometry presents unique challenges and has necessitated the development of a new set of observational tools in order to reduce and analyze both the low-z and high-z CSP sample. We present in this paper the methods used to generate uBVgriYJH light-curve templates based on a sample of 24 high-quality low-z CSP SNe. We also present two methods for determining the distances to the hosts of SN Ia events. A larger sample of 30 low-z SNe Ia in the Hubble flow is used to calibrate these methods. We then apply the method and derive distances to seven galaxies that are so nearby that their motions are not dominated by the Hubble flow.

  18. The Carnegie Supernova Project: Light Curve Fitting with SNooPy

    CERN Document Server

    Burns, Christopher R; Phillips, M M; Katner, ShiAnne; Persson, S E; Madore, Barry F; Freedman, Wendy L; Boldt, Luis; Campillay, Abdo; Contreras, Carlos; Folatelli, Gaston; Gonzalez, Sergio; Krzeminski, Wojtek; Morrell, Nidia; Salgado, Francisco; Suntzeff, Nicholas B

    2010-01-01

    In providing an independent measure of the expansion history of the Universe, the Carnegie Supernova Project (CSP) has observed 71 high-z Type Ia supernovae (SNe Ia) in the near-infrared bands Y and J. These can be used to construct rest-frame i-band light curves which, when compared to a low-z sample, yield distance moduli that are less sensitive to extinction and/or decline-rate corrections than in the optical. However, working with NIR observed and i-band rest frame photometry presents unique challenges and has necessitated the development of a new set of observational tools in order to reduce and analyze both the low-z and high-z CSP sample. We present in this paper the methods used to generate uBVgriYJH light-curve templates based on a sample of 24 high-quality low-z CSP SNe. We also present two methods for determining the distances to the hosts of SN Ia events. A larger sample of 30 low-z SNe Ia in the Hubble Flow are used to calibrate these methods. We then apply the method and derive distances to seve...

  19. The Carnegie Supernova Project: Analysis of the First Sample of Low-Redshift Type-Ia Supernovae

    Science.gov (United States)

    Folatelli, Gaston; Phillips, M. M.; Burns, C. R.; Contreras, C.; Hamuy, M.; Freedman, W. L.; Persson, S. E.; Stritzinger, M.; Suntzeff, N. B.; Krisciunas, K.; Boldt, L.; Gonzalez, S.; Krzeminski, W.; Morrell, N.; Roth, M.; Salgado, F.; Madore, B. F.; Murphy, D.; Wyatt, P.; Li, W.; Filippenko, A. V.

    2009-05-01

    We present the analysis of the first set of 35 low-redshift (zcolors at maximum light. This is used to derive color excesses and thus study the properties of the reddening law in the host galaxies, with the advantage of combining optical and NIR bands. We study the calibration of absolute peak magnitudes in all bands using a two-parameter bilinear fit to decline rates and colors or, alternatively, color excesses. We obtain dispersions of 0.1_ 0.2 mag, depending on the filter--color combinations, and low values of the reddening-law parameter RV 1_ 2. We further investigate the validity of Type-Ia supernovae as true standard candles in the NIR, requiring no correction for decline rate.

  20. An Expanded HST/WFC3 Survey of M83: Project Overview and Targeted Supernova Remnant Search

    CERN Document Server

    Blair, William P; Dopita, Michael A; Ghavamian, Parviz; Hammer, Derek; Kuntz, K D; Long, Knox S; Soria, Roberto; Whitmore, Bradley C; Winkler, P Frank

    2014-01-01

    We present an optical/NIR imaging survey of the face-on spiral galaxy M83, using data from the Hubble Space Telescope Wide Field Camera 3 (WFC3). Seven fields are used to cover a large fraction of the inner disk, with observations in nine broadband and narrowband filters. In conjunction with a deep Chandra survey and other new radio and optical ground-based work, these data enable a broad range of science projects to be pursued. We provide an overview of the WFC3 data and processing and then delve into one topic, the population of young supernova remnants. We used a search method targeted toward soft X-ray sources to identify 26 new supernova remnants. Many compact emission nebulae detected in [Fe II] 1.644 micron align with known remnants and this diagnostic has also been used to identify many new remnants, some of which are hard to find with optical images. We include 37 previously identified supernova remnants that the data reveal to be <0.5'' in angular size and thus are difficult to characterize from ...

  1. A kinetic and Kinematic analysis in two assessment situation with bench press. Free Weight vs Smith Machine. Project pilot.

    Directory of Open Access Journals (Sweden)

    I. J. Bautista

    2012-06-01

    Full Text Available This pilot study examines the most relevant kinetic and kinematics variables in two bench press exercises; Smith Machine (PMS vs. free weights (PBL. Two trained subjects participated in the research following informed consent. To determine the maximum load (1-RM, two incremental protocols were used for PMS and PBL. Subject 1 (S-1 produced force values of 770N and 837N, peak force of 28ms and 12ms, in PBL and PMS respectively. Values for subject 2 (S-2 were 693N and 849N, PMF of 60ms and 66ms for PBL and PMS respectively. Detailed analyses of the following variables were performed; velocity curves for each load, the “sticking period”, the distances of grip width, and changes in bar inclination during the ascent phase of the lift were examined. The key findings of this research, and the basis for future research demonstrate that PBL is recommended as a training exercise, while more reliable information regarding force variables can be attained through using PMS in measurement sessions. Key Words: Bench Press, smith machine, free weight, strength assessment, upper limb.

  2. Galaxy Zoo Supernovae

    CERN Document Server

    Smith, A M; Sullivan, M; Lintott, C J; Nugent, P E; Botyanszki, J; Kasliwal, M; Quimby, R; Bamford, S P; Fortson, L F; Schawinski, K; Hook, I; Blake, S; Podsiadlowski, P; Joensson, J; Gal-Yam, A; Arcavi, I; Howell, D A; Bloom, J S; Jacobsen, J; Kulkarni, S R; Law, N M; Ofek, E O; Walters, R

    2010-01-01

    This paper presents the first results from a new citizen science project: Galaxy Zoo Supernovae. This proof of concept project uses members of the public to identify supernova candidates from the latest generation of wide-field imaging transient surveys. We describe the Galaxy Zoo Supernovae operations and scoring model, and demonstrate the effectiveness of this novel method using imaging data and transients from the Palomar Transient Factory (PTF). We examine the results collected over the period April-July 2010, during which nearly 14,000 supernova candidates from PTF were classified by more than 2,500 individuals within a few hours of data collection. We compare the transients selected by the citizen scientists to those identified by experienced PTF scanners, and find the agreement to be remarkable - Galaxy Zoo Supernovae performs comparably to the PTF scanners, and identified as transients 93% of the ~130 spectroscopically confirmed SNe that PTF located during the trial period (with no false positive iden...

  3. Supernova detection

    Energy Technology Data Exchange (ETDEWEB)

    Nakahata, Masayuki [Kamioka Observatory, Institute for Cosmic Ray research, University of Tokyo, Higashi-Mozumi, Kamioka-cho, Hida-shi, Gifu, Japan, 506-1205 (Japan)], E-mail: nakahata@suketto.icrr.u-tokyo.ac.jp

    2008-11-01

    The detection of supernova neutrinos is reviewed, focusing on the current status of experiments to detect supernova burst neutrinos and supernova relic neutrinos. The capabilities of each detector currently operating and in development are assessed and the likely neutrino yield for a future supernova is estimated. It is expected that much more information will be obtained if a supernova burst were to occur in our Galaxy than was obtained for supernova SN1987A. The detection of supernova relic neutrinos is considered and it is concluded that a large volume detector with a neutron tagging technique is necessary.

  4. The SILCC project - III. Regulation of star formation and outflows by stellar winds and supernovae

    Science.gov (United States)

    Gatto, Andrea; Walch, Stefanie; Naab, Thorsten; Girichidis, Philipp; Wünsch, Richard; Glover, Simon C. O.; Klessen, Ralf S.; Clark, Paul C.; Peters, Thomas; Derigs, Dominik; Baczynski, Christian; Puls, Joachim

    2017-04-01

    We study the impact of stellar winds and supernovae on the multiphase interstellar medium using three-dimensional hydrodynamical simulations carried out with FLASH. The selected galactic disc region has a size of (500 pc)2 × ±5 kpc and a gas surface density of 10 M⊙ pc-2. The simulations include an external stellar potential and gas self-gravity, radiative cooling and diffuse heating, sink particles representing star clusters, stellar winds from these clusters that combine the winds from individual massive stars by following their evolution tracks, and subsequent supernova explosions. Dust and gas (self-) shielding is followed to compute the chemical state of the gas with a chemical network. We find that stellar winds can regulate star (cluster) formation. Since the winds suppress the accretion of fresh gas soon after the cluster has formed, they lead to clusters that have lower average masses (102-104.3 M⊙) and form on shorter time-scales (10-3-10 Myr). In particular, we find an anticorrelation of cluster mass and accretion time-scale. Without winds, the star clusters easily grow to larger masses for ∼5 Myr until the first supernova explodes. Overall, the most massive stars provide the most wind energy input, while objects beginning their evolution as B-type stars contribute most of the supernova energy input. A significant outflow from the disc (mass loading ≳1 at 1 kpc) can be launched by thermal gas pressure if more than 50 per cent of the volume near the disc mid-plane can be heated to T > 3 × 105 K. Stellar winds alone cannot create a hot volume-filling phase. The models that are in best agreement with observed star formation rates drive either no outflows or weak outflows.

  5. Galaxy Zoo Supernovae

    Science.gov (United States)

    Smith, A. M.; Lynn, S.; Sullivan, M.; Lintott, C. J.; Nugent, P. E.; Botyanszki, J.; Kasliwal, M.; Quimby, R.; Bamford, S. P.; Fortson, L. F.; Schawinski, K.; Hook, I.; Blake, S.; Podsiadlowski, P.; Jönsson, J.; Gal-Yam, A.; Arcavi, I.; Howell, D. A.; Bloom, J. S.; Jacobsen, J.; Kulkarni, S. R.; Law, N. M.; Ofek, E. O.; Walters, R.

    2011-04-01

    This paper presents the first results from a new citizen science project: Galaxy Zoo Supernovae. This proof-of-concept project uses members of the public to identify supernova candidates from the latest generation of wide-field imaging transient surveys. We describe the Galaxy Zoo Supernovae operations and scoring model, and demonstrate the effectiveness of this novel method using imaging data and transients from the Palomar Transient Factory (PTF). We examine the results collected over the period 2010 April-July, during which nearly 14 000 supernova candidates from the PTF were classified by more than 2500 individuals within a few hours of data collection. We compare the transients selected by the citizen scientists to those identified by experienced PTF scanners and find the agreement to be remarkable - Galaxy Zoo Supernovae performs comparably to the PTF scanners and identified as transients 93 per cent of the ˜130 spectroscopically confirmed supernovae (SNe) that the PTF located during the trial period (with no false positive identifications). Further analysis shows that only a small fraction of the lowest signal-to-noise ratio detections (r > 19.5) are given low scores: Galaxy Zoo Supernovae correctly identifies all SNe with ≥8σ detections in the PTF imaging data. The Galaxy Zoo Supernovae project has direct applicability to future transient searches, such as the Large Synoptic Survey Telescope, by both rapidly identifying candidate transient events and via the training and improvement of existing machine classifier algorithms. This publication has been made possible by the participation of more than 10 000 volunteers in the Galaxy Zoo Supernovae project ().

  6. Matching Supernovae to Galaxies

    Science.gov (United States)

    Kohler, Susanna

    2016-12-01

    One of the major challenges for modern supernova surveys is identifying the galaxy that hosted each explosion. Is there an accurate and efficient way to do this that avoids investing significant human resources?Why Identify Hosts?One problem in host galaxy identification. Here, the supernova lies between two galaxies but though the centroid of the galaxy on the right is closer in angular separation, this may be a distant background galaxy that is not actually near the supernova. [Gupta et al. 2016]Supernovae are a critical tool for making cosmological predictions that help us to understand our universe. But supernova cosmology relies on accurately identifying the properties of the supernovae including their redshifts. Since spectroscopic followup of supernova detections often isnt possible, we rely on observations of the supernova host galaxies to obtain redshifts.But how do we identify which galaxy hosted a supernova? This seems like a simple problem, but there are many complicating factors a seemingly nearby galaxy could be a distant background galaxy, for instance, or a supernovas host could be too faint to spot.The authors algorithm takes into account confusion, a measure of how likely the supernova is to be mismatched. In these illustrations of low (left) and high (right) confusion, the supernova is represented by a blue star, and the green circles represent possible host galaxies. [Gupta et al. 2016]Turning to AutomationBefore the era of large supernovae surveys, searching for host galaxies was done primarily by visual inspection. But current projects like the Dark Energy Surveys Supernova Program is finding supernovae by the thousands, and the upcoming Large Synoptic Survey Telescope will likely discover hundreds of thousands. Visual inspection will not be possible in the face of this volume of data so an accurate and efficient automated method is clearly needed!To this end, a team of scientists led by Ravi Gupta (Argonne National Laboratory) has recently

  7. The SILCC project: III. Regulation of star formation and outflows by stellar winds and supernovae

    CERN Document Server

    Gatto, A; Naab, T; Girichidis, P; Wünsch, R; Glover, S C O; Klessen, R S; Clark, P C; Peters, T; Derigs, D; Baczynski, C; Puls, J

    2016-01-01

    We study the impact of stellar winds and supernovae on the multi-phase interstellar medium using three-dimensional hydrodynamical simulations carried out with FLASH. The selected galactic disc region has a size of (500 pc)$^2$ x $\\pm$ 5 kpc and a gas surface density of 10 M$_{\\odot}$/pc$^2$. The simulations include an external stellar potential and gas self-gravity, radiative cooling and diffuse heating, sink particles representing star clusters, stellar winds from these clusters which combine the winds from indi- vidual massive stars by following their evolution tracks, and subsequent supernova explosions. Dust and gas (self-)shielding is followed to compute the chemical state of the gas with a chemical network. We find that stellar winds can regulate star (cluster) formation. Since the winds suppress the accretion of fresh gas soon after the cluster has formed, they lead to clusters which have lower average masses (10$^2$ - 10$^{4.3}$ M$_{\\odot}$) and form on shorter timescales (10$^{-3}$ - 10 Myr). In part...

  8. Adam Smith, Behavioral Economist

    National Research Council Canada - National Science Library

    Ashraf, Nava; Camerer, Colin F; Loewenstein, George

    2005-01-01

    Adam Smith's psychological perspective in The Theory of Moral Sentiments is remarkably similar to "dual-process" frameworks advanced by psychologists, neuroscientists, and more recently by behavioral...

  9. Fractional smith chart theory

    KAUST Repository

    Shamim, Atif

    2011-03-01

    For the first time, a generalized Smith chart is introduced here to represent fractional order circuit elements. It is shown that the standard Smith chart is a special case of the generalized fractional order Smith chart. With illustrations drawn for both the conventional integer based lumped elements and the fractional elements, a graphical technique supported by the analytical method is presented to plot impedances on the fractional Smith chart. The concept is then applied towards impedance matching networks, where the fractional approach proves to be much more versatile and results in a single element matching network for a complex load as compared to the two elements in the conventional approach. © 2010 IEEE.

  10. Joannes Jacobus Smith

    NARCIS (Netherlands)

    Lam, H.J.

    1937-01-01

    J. J. Smith was born June 29th, 1867, at Antwerp, where his father was the director of the Netherlands’ Railway Post Office. In 1872 the family moved to Utrecht and in 1875 to Amsterdam. Smith spent his school days in the capital. His leisure hours were occupied by growing and sketching plants and t

  11. Smith Tackles Oakland Unified

    Science.gov (United States)

    Mellon, Ericka

    2011-01-01

    As a 20-something, Anthony "Tony" Smith had fulfilled one dream: playing professional football for the Green Bay Packers and the San Francisco 49ers. Next up, he thought, was law school, but a former mentor reminded him that he is a teacher. Smith never became a classroom teacher, but his background in sports--where he learned the power…

  12. Spectroscopy of High-Redshift Supernovae from the ESSENCE Project: The First Four Years

    CERN Document Server

    Foley, R J; Blondin, S; Chornock, R; Silverman, J M; Challis, P; Clocchiatti, A; Filippenko, A V; Kirshner, R P; Leibundgut, B; Sollerman, J; Spyromilio, J; Tonry, J L; Davis, T M; Garnavich, P M; Jha, S W; Krisciunas, K; Li, W; Pignata, G; Rest, A; Riess, A G; Schmidt, B P; Smith, R C; Stubbs, C W; Tucker, B E; Wood-Vasey, W M

    2008-01-01

    We present the results of spectroscopic observations from the ESSENCE high-redshift supernova (SN) survey during its first four years of operation. This sample includes spectra of all SNe Ia whose light curves were presented by Miknaitis et al. (2007) and used in the cosmological analyses of Davis et al. (2007) and Wood-Vasey et al. (2007). The sample represents 273 hours of spectroscopic observations with 6.5 - 10-m-class telescopes of objects detected and selected for spectroscopy by the ESSENCE team. We present 174 spectra of 156 objects. Combining this sample with that of Matheson et al. (2005), we have a total sample of 329 spectra of 274 objects. From this, we are able to spectroscopically classify 118 Type Ia SNe. As the survey has matured, the efficiency of classifying SNe Ia has remained constant while we have observed both higher-redshift SNe Ia and SNe Ia farther from maximum brightness. Examining the subsample of SNe Ia with host-galaxy redshifts shows that redshifts derived from only the SN Ia sp...

  13. Supernova VLBI

    Science.gov (United States)

    Bartel, N.

    2009-08-01

    We review VLBI observations of supernovae over the last quarter century and discuss the prospect of imaging future supernovae with space VLBI in the context of VSOP-2. From thousands of discovered supernovae, most of them at cosmological distances, ˜50 have been detected at radio wavelengths, most of them in relatively nearby galaxies. All of the radio supernovae are Type II or Ib/c, which originate from the explosion of massive progenitor stars. Of these, 12 were observed with VLBI and four of them, SN 1979C, SN 1986J, SN 1993J, and SN 1987A, could be imaged in detail, the former three with VLBI. In addition, supernovae or young supernova remnants were discovered at radio wavelengths in highly dust-obscured galaxies, such as M82, Arp 299, and Arp 220, and some of them could also be imaged in detail. Four of the supernovae so far observed were sufficiently bright to be detectable with VSOP-2. With VSOP-2 the expansion of supernovae can be monitored and investigated with unsurpassed angular resolution, starting as early as the time of the supernova's transition from its opaque to transparent stage. Such studies can reveal, in a movie, the aftermath of a supernova explosion shortly after shock break out.

  14. Supernova explosions

    CERN Document Server

    Branch, David

    2017-01-01

    Targeting advanced students of astronomy and physics, as well as astronomers and physicists contemplating research on supernovae or related fields, David Branch and J. Craig Wheeler offer a modern account of the nature, causes and consequences of supernovae, as well as of issues that remain to be resolved. Owing especially to (1) the appearance of supernova 1987A in the nearby Large Magellanic Cloud, (2) the spectacularly successful use of supernovae as distance indicators for cosmology, (3) the association of some supernovae with the enigmatic cosmic gamma-ray bursts, and (4) the discovery of a class of superluminous supernovae, the pace of supernova research has been increasing sharply. This monograph serves as a broad survey of modern supernova research and a guide to the current literature. The book’s emphasis is on the explosive phases of supernovae. Part 1 is devoted to a survey of the kinds of observations that inform us about supernovae, some basic interpreta tions of such data, and an overview of t...

  15. 77 FR 23658 - Six Rivers National Forest, Gasquet Ranger District, California, The Smith River National...

    Science.gov (United States)

    2012-04-20

    ... Smith River National Recreation Area Restoration and Motorized Travel Management Project AGENCY: Forest...-pacificsouthwest-six-rivers@fs.fed.us . Please insure that ``Smith River NRA Restoration and Motorized Travel... UARs totaling 80 miles. The project encompasses the Smith River NRA and Gasquet Ranger...

  16. Aspherical supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Kasen, Daniel Nathan [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    Although we know that many supernovae are aspherical, the exact nature of their geometry is undetermined. Because all the supernovae we observe are too distant to be resolved, the ejecta structure can't be directly imaged, and asymmetry must be inferred from signatures in the spectral features and polarization of the supernova light. The empirical interpretation of this data, however, is rather limited--to learn more about the detailed supernova geometry, theoretical modeling must been undertaken. One expects the geometry to be closely tied to the explosion mechanism and the progenitor star system, both of which are still under debate. Studying the 3-dimensional structure of supernovae should therefore provide new break throughs in our understanding. The goal of this thesis is to advance new techniques for calculating radiative transfer in 3-dimensional expanding atmospheres, and use them to study the flux and polarization signatures of aspherical supernovae. We develop a 3-D Monte Carlo transfer code and use it to directly fit recent spectropolarimetric observations, as well as calculate the observable properties of detailed multi-dimensional hydrodynamical explosion simulations. While previous theoretical efforts have been restricted to ellipsoidal models, we study several more complicated configurations that are tied to specific physical scenarios. We explore clumpy and toroidal geometries in fitting the spectropolarimetry of the Type Ia supernova SN 2001el. We then calculate the observable consequences of a supernova that has been rendered asymmetric by crashing into a nearby companion star. Finally, we fit the spectrum of a peculiar and extraordinarily luminous Type Ic supernova. The results are brought to bear on three broader astrophysical questions: (1) What are the progenitors and the explosion processes of Type Ia supernovae? (2) What effect does asymmetry have on the observational diversity of Type Ia supernovae, and hence their use in cosmology? (3

  17. Aspherical supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Kasen, Daniel Nathan

    2004-05-21

    Although we know that many supernovae are aspherical, the exact nature of their geometry is undetermined. Because all the supernovae we observe are too distant to be resolved, the ejecta structure can't be directly imaged, and asymmetry must be inferred from signatures in the spectral features and polarization of the supernova light. The empirical interpretation of this data, however, is rather limited--to learn more about the detailed supernova geometry, theoretical modeling must been undertaken. One expects the geometry to be closely tied to the explosion mechanism and the progenitor star system, both of which are still under debate. Studying the 3-dimensional structure of supernovae should therefore provide new break throughs in our understanding. The goal of this thesis is to advance new techniques for calculating radiative transfer in 3-dimensional expanding atmospheres, and use them to study the flux and polarization signatures of aspherical supernovae. We develop a 3-D Monte Carlo transfer code and use it to directly fit recent spectropolarimetric observations, as well as calculate the observable properties of detailed multi-dimensional hydrodynamical explosion simulations. While previous theoretical efforts have been restricted to ellipsoidal models, we study several more complicated configurations that are tied to specific physical scenarios. We explore clumpy and toroidal geometries in fitting the spectropolarimetry of the Type Ia supernova SN 2001el. We then calculate the observable consequences of a supernova that has been rendered asymmetric by crashing into a nearby companion star. Finally, we fit the spectrum of a peculiar and extraordinarily luminous Type Ic supernova. The results are brought to bear on three broader astrophysical questions: (1) What are the progenitors and the explosion processes of Type Ia supernovae? (2) What effect does asymmetry have on the observational diversity of Type Ia supernovae, and hence their use in cosmology? (3

  18. The SILCC (SImulating the LifeCycle of molecular Clouds) project: I. Chemical evolution of the supernova-driven ISM

    CERN Document Server

    Walch, S K; Naab, T; Gatto, A; Glover, S C O; Wünsch, R; Klessen, R S; Clark, P C; Peters, T; Baczynski, C

    2014-01-01

    The SILCC project (SImulating the Life-Cycle of molecular Clouds) aims at a more self-consistent understanding of the interstellar medium (ISM) on small scales and its link to galaxy evolution. We simulate the evolution of the multi-phase ISM in a 500 pc x 500 pc x 10 kpc region of a galactic disc, with a gas surface density of $\\Sigma_{_{\\rm GAS}} = 10 \\;{\\rm M}_\\odot/{\\rm pc}^2$. The Flash 4.1 simulations include an external potential, self-gravity, magnetic fields, heating and radiative cooling, time-dependent chemistry of H$_2$ and CO considering (self-) shielding, and supernova (SN) feedback. We explore SN explosions at different (fixed) rates in high-density regions (peak), in random locations (random), in a combination of both (mixed), or clustered in space and time (clustered). Only random or clustered models with self-gravity (which evolve similarly) are in agreement with observations. Molecular hydrogen forms in dense filaments and clumps and contributes 20% - 40% to the total mass, whereas most of ...

  19. Adam Smith and dependency.

    Science.gov (United States)

    Ozler, Sule

    2012-06-01

    The focus of this paper is the works and life of Adam Smith, who is widely recognized as the father and founder of contemporary economics. Latent content analysis is applied to his seminal text in economics, An Inquiry into the Nature and Causes of the Wealth of Nations (1776). The results reveal that Smith considers dependence on others a problem and sees the solution to this problem in impersonalized interdependence. In addition, his views on social dependency and personal dependency, reflected in his Lectures on Jurisprudence (1963) and The Theory of Moral Sentiments (1759), are analyzed. This analysis suggests a central tension between dependence and independence in Smith's writings. The personal dependency patterns he exhibited in his life, which also suggest a tension between dependence and independence, are identified through a reading of his biographies. Based on insights from psychoanalytic literature, this paper proposes that developing the ideas in the Wealth of Nations was part of Smith's creative solution to this tension. In particular, his solution to one individual's dependence on another was through a system of impersonalized interdependence. In other words, Smith defended against his personal dependence through his economic theorizing.

  20. Zadie Smith: un homenaje

    Directory of Open Access Journals (Sweden)

    Rivera de la Cruz, Marta

    2009-06-01

    Full Text Available Considerada por la prestigiosa revista Granta uno de los nombres propios de las letras anglosajonas, Zadie Smith irrumpió en la escena literaria con Dientes blancos cuando contaba con poco más de veinte años. Su extraordinario talento unido a su extrema juventud sorprendieron a la crítica, pero también al público y a los medios de comunicación, que no tardaron en hacer de ella un nuevo icono de la literatura moderna. Zadie Smith ha pasado los últimos años escribiendo y huyendo a la vez de la feria de vanidades de la fama, que amenazaba con oscurecer sus dotes de narradora. Es una escritora total, cuya tercera novela, Sobre la belleza, la ha consagrado de forma definitiva.

  1. Portrait of Waldo Smith

    Science.gov (United States)

    Spilhaus, Fred

    2009-01-01

    In 1944, Waldo Smith was looking for a place where he could make a difference. He had taught in universities in the United States and Turkey, and he had worked as an engineer in the field of hydrology in the United States. Somehow, a chance meeting with John Adam Fleming, AGU's long-time General Secretary, led to Waldo's becoming the first executive officer employed by the Union. That, in turn, brought him the opportunity to make a difference.

  2. Smoking Supernovae

    CERN Document Server

    Gomez, H L; Dunne, L

    2007-01-01

    The question "Are supernovae important sources of dust?" is a contentious one. Observations with the Infrared Astronomical Satellite (IRAS) and the Infrared Space Observatory (ISO) only detected very small amounts of hot dust in supernova remnants. Here, we review observations of two young Galactic remnants with the Submillimetre Common User Bolometer Array (SCUBA), which imply that large quantities of dust are produced by supernovae. The association of dust with the Cassiopeia A remnant is in question due to the contamination of foreground material. In this article, we compare the emission from cold dust with CO emission towards Kepler's supernova remnant. We detect very little CO at the location of the submillimetre peaks. A comparison of masses from the CO and the dust clouds are made, and we estimate the 3 sigma upper limit on the gas-to-dust ratios to range from 25 - 65 suggesting that we cannot yet rule out freshly-formed or swept up circumstellar dust in Kepler's supernova remnant.

  3. SOUSA's Swift Supernova Siblings

    CERN Document Server

    Brown, Peter J

    2015-01-01

    Swift has observed over three hundred supernovae in its first ten years. Photometry from the Ultra-Violet Optical Telescope (UVOT) is being compiled in the Swift Optical/Ultraviolet Supernovae Archive (SOUSA). The diversity of supernovae leads to a wide dynamic range of intrinsic properties. The intrinsic UV brightness of supernovae as a function of type and epoch allows one to understand the distance ranges at which Swift can reliably detect supernovae. The large Swift sample also includes supernovae from the same galaxy as other Swift supernovae. Through the first ten years, these families include 34 supernovae from 16 host galaxies (two galaxies have each hosted three Swift supernovae).

  4. Simulating Supernova Light Curves

    Energy Technology Data Exchange (ETDEWEB)

    Even, Wesley Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dolence, Joshua C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-05

    This report discusses supernova light simulations. A brief review of supernovae, basics of supernova light curves, simulation tools used at LANL, and supernova results are included. Further, it happens that many of the same methods used to generate simulated supernova light curves can also be used to model the emission from fireballs generated by explosions in the earth’s atmosphere.

  5. Adam Smith on population.

    Science.gov (United States)

    Spengler, J J

    1970-11-01

    Abstract Adam Smith dealt with questions of population mainly in his Wealth of Nations. His discussion falls roughly under five heads and reflects in considerable measure his image of the English economy. (1) A country's population capacity, given the average level of consumption, was conditioned by the stock of land, the skill with which it was cultivated, and the degree to which division of labour could be increased and thereby augment output for domestic use and sale in external markets. (2) Growth of population was essentially in response to growth of the demand for labour and served to increase division of labour. (3) The social mechanisms underlying elevation of the scale of living are touched upon, and in an optimistic spirit. (4) The distribution of a country's population responded to its progress in opulence, with the rate of this progress conditioned by the degree to which inappropriate (e.g. mercantilist) policies were avoided. (5) Smith dealt briefly with such matters as colonies, education, size of economy, environmental influences, and public policy, all of which he recognized as significant for the quantity and quality of a country's numbers.

  6. The CHilean Automatic Supernova sEarch

    DEFF Research Database (Denmark)

    Hamuy, M.; Pignata, G.; Maza, J.

    2012-01-01

    The CHilean Automatic Supernova sEarch (CHASE) project began in 2007 with the goal to discover young, nearby southern supernovae in order to (1) better understand the physics of exploding stars and their progenitors, and (2) refine the methods to derive extragalactic distances. During the first...

  7. Supernova Photometric Classification Challenge

    CERN Document Server

    Kessler, Richard; Jha, Saurabh; Kuhlmann, Stephen

    2010-01-01

    We have publicly released a blinded mix of simulated SNe, with types (Ia, Ib, Ic, II) selected in proportion to their expected rate. The simulation is realized in the griz filters of the Dark Energy Survey (DES) with realistic observing conditions (sky noise, point spread function and atmospheric transparency) based on years of recorded conditions at the DES site. Simulations of non-Ia type SNe are based on spectroscopically confirmed light curves that include unpublished non-Ia samples donated from the Carnegie Supernova Project (CSP), the Supernova Legacy Survey (SNLS), and the Sloan Digital Sky Survey-II (SDSS-II). We challenge scientists to run their classification algorithms and report a type for each SN. A spectroscopically confirmed subset is provided for training. The goals of this challenge are to (1) learn the relative strengths and weaknesses of the different classification algorithms, (2) use the results to improve classification algorithms, and (3) understand what spectroscopically confirmed sub-...

  8. The CHilean Automatic Supernova sEarch

    DEFF Research Database (Denmark)

    Hamuy, M.; Pignata, G.; Maza, J.

    2012-01-01

    The CHilean Automatic Supernova sEarch (CHASE) project began in 2007 with the goal to discover young, nearby southern supernovae in order to (1) better understand the physics of exploding stars and their progenitors, and (2) refine the methods to derive extragalactic distances. During the first...... four years of operation, CHASE has produced more than 130 supernovae, being the most successful project of its type in the southern hemisphere. Here we describe the project and present illustrative examples of CHASE discoveries of particular relevance....

  9. Genetics Home Reference: Smith-Magenis syndrome

    Science.gov (United States)

    ... Genetics Home Health Conditions Smith-Magenis syndrome Smith-Magenis syndrome Enable Javascript to view the expand/collapse ... Download PDF Open All Close All Description Smith-Magenis syndrome is a developmental disorder that affects many ...

  10. Supernova Forensics

    Science.gov (United States)

    Soderberg, Alicia M.

    2014-01-01

    For decades, the study of stellar explosions -- supernovae -- have focused almost exclusively on the strong optical emission that dominates the bolometric luminosity in the days following the ultimate demise of the star. Yet many of the leading breakthroughs in our understanding of stellar death have been enabled by obtaining data at other wavelengths. For example, I have shown that 1% of all supernovae give rise to powerful relativistic jets, representing the biggest bangs in the Universe since the Big Bang. My recent serendipitous X-ray discovery of a supernova in the act of exploding (“in flagrante delicto”) revealed a novel technique to discover new events and provide clues on the shock physics at the heart of the explosion. With the advent of sensitive new radio telescopes, my research group combines clues from across the electromagnetic spectrum (radio to gamma-ray), leading us to a holistic study of stellar death, the physics of the explosions, and their role in fertilizing the Universe with new elements, by providing the community with cosmic autopsy reports.

  11. Smith Newton Vehicle Performance Evaluation - Cumulative (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-08-01

    The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory is evaluating and documenting the performance of electric and plug-in hybrid electric drive systems in medium-duty trucks across the nation. U.S. companies participating in this evaluation project received funding from the American Recovery and Reinvestment Act to cover part of the cost of purchasing these vehicles. Through this project, Smith Electric Vehicles is building and deploying 500 all-electric medium-duty trucks that will be deployed by a variety of companies in diverse climates across the country.

  12. The Supernova - A Stellar Spectacle.

    Science.gov (United States)

    Straka, W. C.

    This booklet is part of an American Astronomical Society curriculum project designed to provide teaching materials to teachers of secondary school chemistry, physics, and earth science. The following topics concerning supernovae are included: the outburst as observed and according to theory, the stellar remnant, the nebular remnant, and a summary…

  13. Radio Supernovae: Circum-Stellar Investigation (C.S.I.) of Supernova Progenitor Stars

    Science.gov (United States)

    2009-02-24

    ar X iv :0 90 2. 40 59 v1 [ as tr o- ph .H E ] 2 4 Fe b 20 09 Radio Supernovae : Circum-Stellar Investigation (C.S.I.) of Supernova Progenitor...FEB 2009 2. REPORT TYPE 3. DATES COVERED 00-00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Radio Supernovae : Circum-Stellar Investigation (C.S.I...of Supernova Progenitor Stars 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f

  14. Smith-Magenis syndrome.

    Science.gov (United States)

    De Leersnyder, H

    2013-01-01

    Smith-Magenis syndrome (SMS) is a mental retardation syndrome with distinctive behavioral characteristics, dysmorphic features, and congenital anomalies ascribed to an interstitial deletion of chromosome 17p11.2. Severe sleep disturbances and maladaptive daytime behavior have been linked to an abnormal circadian rhythm of melatonin with a diurnal instead of nocturnal secretion of this hormone. SMS provides a demonstration of a biological basis for sleep disorder in a genetic disease. Considering that clock genes mediate the generation of circadian rhythm, haploinsufficiency for a circadian system gene, mapping to chromosome 17p11.2, may cause the inversion of the melatonin circadian rhythm in SMS. The disorder of circadian timing in SMS may also affect entrainment pathway (retinohypothalamic tract), pacemaker functions (suprachiasmatic nuclei), or synthesis and release of melatonin by the pineal gland. Elucidating pathophysiological mechanisms of behavioral phenotypes in genetic disease can provide an original therapeutic approach in SMS: blockade of endogenous melatonin production during the day combined with exogenous melatonin administration in the evening.

  15. Current research at Neal Smith National Wildlife Refuge as of June 3, 2005

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a list of research projects in progress at Neal Smith National Wildlife Refuge as of June 3, 2005. For each project, the principle investigator, the...

  16. Detection of Supernova Neutrinos

    OpenAIRE

    Bekman, B.; Holeczek, J.; Kisiel, J4

    2004-01-01

    Matter effects on neutrino oscillations in both, a supernova and the Earth, change the observed supernova neutrino spectra. We calculate the expected number of supernova neutrino interactions for ICARUS, SK and SNO detectors as a function of the distance which they traveled in the Earth. Calculations are performed for supernova type II at 10kpc from the Earth, using standard supernova neutrino fluxes described by thermal Fermi--Dirac distributions and the PREM I Earth matter density profile.

  17. Standardization of type Ia supernovae

    CERN Document Server

    Coelho, Rodrigo C V; Reis, Ribamar R R; Siffert, Beatriz B

    2014-01-01

    Type Ia supernovae (SNe Ia) have been intensively investigated due to its great homogeneity and high luminosity, which make it possible to use them as standardizable candles for the determination of cosmological parameters. In 2011, the physics Nobel prize was awarded for the discovery of the accelerating expansion of the Universe through observations of distant supernovae. This is a pedagogical article, aimed at those starting their study of that subject, in which we dwell on some topics related to the analysis of SNe Ia and their use in luminosity distance estimators. Here we investigate their spectral properties and light curve standardization, paying careful attention to the fundamental quantities directly related to the SNe Ia observables. Finally, we describe our own step-by-step implementation of a classical light curve fi?tter, the stretch, applying it to real data from the Carnegie Supernova Project.

  18. First supernova companion star found

    Science.gov (United States)

    2004-01-01

    discovery possible.” Supernovae occur when a star of more than about eight times the mass of the Sun reaches the end of its nuclear fuel reserves and can no longer produce enough energy to keep the star from collapsing under its own immense weight. The core of the star collapses, and the outer layers are ejected in a fast-moving shock wave. This huge energy release causes the visible supernova we see. While astronomers are convinced that observations will match this theoretical model, they are in the embarrassing position that they have confidently identified only two stars that later exploded as supernovae - the precursors of supernovae 1987A and 1993J. There have been more than 2000 supernovae discovered in galaxies beyond the Milky Way and there appear to be about eight distinct sub-classes. However identifying which stars produce which flavours has proved incredibly difficult. This team has now embarked on a parallel project with the Hubble Space Telescope to image a large number of galaxies and then wait patiently for a supernova to explode. Supernovae appear in spiral galaxies like M81 on average once every 100 years or so. The team, led by Stephen Smartt, hope to increase the numbers of supernova progenitors known from 2 to 20 over the next five years. Notes for editors The team is composed of Stephen J. Smartt and Justyn R. Maund (University of Cambridge, UK), Rolf. P. Kudritzki (University of Hawaii, USA), Philipp Podsiadlowski (University of Oxford, UK) and Gerry F. Gilmore (University of Cambridge, UK). Animations of the discovery and general Hubble Space Telescope background footage are available from http://www.spacetelescope.org/video/heic0401_vnr.html

  19. Rates and progenitors of type Ia supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Wood-Vasey, William Michael [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    The remarkable uniformity of Type Ia supernovae has allowed astronomers to use them as distance indicators to measure the properties and expansion history of the Universe. However, Type Ia supernovae exhibit intrinsic variation in both their spectra and observed brightness. The brightness variations have been approximately corrected by various methods, but there remain intrinsic variations that limit the statistical power of current and future observations of distant supernovae for cosmological purposes. There may be systematic effects in this residual variation that evolve with redshift and thus limit the cosmological power of SN Ia luminosity-distance experiments. To reduce these systematic uncertainties, we need a deeper understanding of the observed variations in Type Ia supernovae. Toward this end, the Nearby Supernova Factory has been designed to discover hundreds of Type Ia supernovae in a systematic and automated fashion and study them in detail. This project will observe these supernovae spectrophotometrically to provide the homogeneous high-quality data set necessary to improve the understanding and calibration of these vital cosmological yardsticks. From 1998 to 2003, in collaboration with the Near-Earth Asteroid Tracking group at the Jet Propulsion Laboratory, a systematic and automated searching program was conceived and executed using the computing facilities at Lawrence Berkeley National Laboratory and the National Energy Research Supercomputing Center. An automated search had never been attempted on this scale. A number of planned future large supernovae projects are predicated on the ability to find supernovae quickly, reliably, and efficiently in large datasets. A prototype run of the SNfactory search pipeline conducted from 2002 to 2003 discovered 83 SNe at a final rate of 12 SNe/month. A large, homogeneous search of this scale offers an excellent opportunity to measure the rate of Type Ia supernovae. This thesis presents a new method for

  20. The Search for Lensed Supernovae

    Science.gov (United States)

    Kohler, Susanna

    2017-01-01

    Lawrence Berkeley National Laboratory have a plan. In a recent publication, Daniel Goldstein and Peter Nugent propose the following clever procedure to apply to data from transient surveys:From the data, select only the supernova candidates that appear to be hosted by quiescent elliptical galaxies.Use the host galaxies photometric redshifts to calculate absolute magnitudes for the supernovae in this sample.Select from this only the supernovae above the maximum absolute magnitude expected for Type Ia supernovae.Supernovae selected in this way are likely tricking us: their apparent hosts are probably not their hosts at all! Instead, the supernova is likely behind the galaxy, and the galaxy is just lensing its light. Using this strategy therefore allows us to select supernova candidates that are most likely to be distant, gravitationally lensed Type Ia supernovae.Redshift distribution of the multiply-imaged Type Ia supernovae the authors estimate will be detectable by ZTF and LSST in their respective 3- and 10-year survey durations. [Goldstein Nugent 2017]A convenient aspect of Goldstein and Nugents technique is that we dont need to be able to resolve the lensed multiple images for discovery. This is useful, because ground-based optical surveys dont have the resolution to see the separate images yet theyll still be useful for discovering multiply-imaged supernovae.Future ProspectsHow useful? Goldstein and Nugent use Monte Carlo simulations to estimate how many multiply-imaged Type Ia supernovae will be discoverable with future survey projects. They find that theZwicky Transient Facility (ZTF), which will begin operating this year, should be able to find up to 10 using this technique in a 3-year search. The Large Synoptic Survey Telescope (LSST), which should start operating in 2022, will be able to find around 500 multiply-imaged Type Ia supernovae in a 10-year survey.CitationDaniel A. Goldstein and Peter E. Nugent 2017 ApJL 834 L5. doi:10.3847/2041-8213/834/1/L5

  1. Luminous Supernovae

    CERN Document Server

    Gal-Yam, Avishay

    2012-01-01

    Supernovae (SNe), the luminous explosions of stars, were observed since antiquity, with typical peak luminosity not exceeding 1.2x10^{43} erg/s (absolute magnitude >-19.5 mag). It is only in the last dozen years that numerous examples of SNe that are substantially super-luminous (>7x10^{43} erg/s; <-21 mag absolute) were well-documented. Reviewing the accumulated evidence, we define three broad classes of super-luminous SN events (SLSNe). Hydrogen-rich events (SLSN-II) radiate photons diffusing out from thick hydrogen layers where they have been deposited by strong shocks, and often show signs of interaction with circumstellar material. SLSN-R, a rare class of hydrogen-poor events, are powered by very large amounts of radioactive 56Ni and arguably result from explosions of very massive stars due to the pair instability. A third, distinct group of hydrogen-poor events emits photons from rapidly-expanding hydrogen-poor material distributed over large radii, and are not powered by radioactivity (SLSN-I). Thes...

  2. More Supernova Surprises

    Science.gov (United States)

    2010-09-24

    SEP 2010 2. REPORT TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND SUBTITLE More Supernova Surprises 5a. CONTRACT NUMBER 5b. GRANT...PERSPECTIVES More Supernova Surprises ASTRONOMY J. Martin Laming Spectroscopic observations of the supernova SN1987A are providing a new window into high...a core-collapse supernova ) have stretched and motivated research that has expanded our knowledge of astrophysics. The brightest such event in

  3. SNO and Supernovae

    CERN Document Server

    Virtue, C J

    2001-01-01

    The Sudbury Neutrino Observatory (SNO) has unique capabilities as a supernova detector. In the event of a galactic supernova there are opportunities, with the data that SNO would collect, to constrain certain intrinsic neutrino properties significantly, to test details of the various models of supernova dynamics, and to provide prompt notification to the astronomical community through the Supernova Early Warning System (SNEWS). This paper consists of a discussion of these opportunities illustrated by some preliminary Monte Carlo results.

  4. The Nearby Supernova Factory

    CERN Document Server

    Wood-Vasey, W M; Lee Byung Cheol; Loken, S; Nugent, P; Perlmutter, S; Siegrist, J L; Wang, L; Antilogus, P; Astier, Pierre; Hardin, D; Pain, R; Copin, Y; Smadja, G; Gangler, E; Castera, A; Adam, G; Bacon, R; Lemonnier, J P; Pecontal, A; Pécontal, E; Kessler, R

    2004-01-01

    The Nearby Supernova Factory (SNfactory) is an ambitious project to find and study in detail approximately 300 nearby Type Ia supernovae (SNe~Ia) at redshifts 0.03

  5. Smith, Adam (1723-90)

    DEFF Research Database (Denmark)

    Bouchet, Dominique

    2015-01-01

    Adam Smith is often said to have been the founder of the science of economics and the father of liberalism in the sphere of economics. In fact he was neither. He lived at a turning point in western economic and political history, one that was littered with disruptive developments. He came up with...

  6. Final Report for the project titled "Enabling Supernova Computations by Integrated Transport and Provisioning Methods Optimized for Dedicated Channels"

    Energy Technology Data Exchange (ETDEWEB)

    Malathi Veeraraghavan

    2007-10-31

    A high-speed optical circuit network is one that offers users rate-guaranteed connectivity between two endpoints, unlike today’s IP-routed Internet in which the rate available to a pair of users fluctuates based on the volume of competing traffic. This particular research project advanced our understanding of circuit networks in two ways. First, transport protocols were developed for circuit networks. In a circuit network, since bandwidth resources are reserved for each circuit on an end-to-end basis (much like how a person reserves a seat on every leg of a multi-segment flight), and the sender is limited to send at the rate of the circuit, there is no possibility of congestion during data transfer. Therefore, no congestion control functions are necessary in a transport protocol designed for circuits. However, error control and flow control are still required because bits can become errored due to noise and interference even on highly reliable optical links, and receivers can, due to multitasking or other reasons, not deplete the receive buffer fast enough to keep up with the sending rate (e.g., if the receiving host is multitasking between receiving a file transfer and some other computation). In this work, we developed two transport protocols for circuits, both of which are described below. Second, this project developed techniques for internetworking different types of connection-oriented networks, which are of two types: circuit-switched or packet-switched. In circuit-switched networks, multiplexing on links is “position based,” where “position” refers to the frequency, time slot, and port (fiber), while connection-oriented packet-switched networks use packet header information to demultiplex packets and switch them from node to node. The latter are commonly referred to as virtual circuit networks. Examples of circuit networks are time-division multiplexed Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) and Wavelength Division

  7. Final Report for the project titled "Enabling Supernova Computations by Integrated Transport and Provisioning Methods Optimized for Dedicated Channels"

    Energy Technology Data Exchange (ETDEWEB)

    Malathi Veeraraghavan

    2007-10-31

    A high-speed optical circuit network is one that offers users rate-guaranteed connectivity between two endpoints, unlike today’s IP-routed Internet in which the rate available to a pair of users fluctuates based on the volume of competing traffic. This particular research project advanced our understanding of circuit networks in two ways. First, transport protocols were developed for circuit networks. In a circuit network, since bandwidth resources are reserved for each circuit on an end-to-end basis (much like how a person reserves a seat on every leg of a multi-segment flight), and the sender is limited to send at the rate of the circuit, there is no possibility of congestion during data transfer. Therefore, no congestion control functions are necessary in a transport protocol designed for circuits. However, error control and flow control are still required because bits can become errored due to noise and interference even on highly reliable optical links, and receivers can, due to multitasking or other reasons, not deplete the receive buffer fast enough to keep up with the sending rate (e.g., if the receiving host is multitasking between receiving a file transfer and some other computation). In this work, we developed two transport protocols for circuits, both of which are described below. Second, this project developed techniques for internetworking different types of connection-oriented networks, which are of two types: circuit-switched or packet-switched. In circuit-switched networks, multiplexing on links is “position based,” where “position” refers to the frequency, time slot, and port (fiber), while connection-oriented packet-switched networks use packet header information to demultiplex packets and switch them from node to node. The latter are commonly referred to as virtual circuit networks. Examples of circuit networks are time-division multiplexed Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) and Wavelength Division

  8. The Distant Type Ia Supernova Rate

    Science.gov (United States)

    Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R. S.; Aldering, G.; Astier, P.; Deustua, S. E.; Fruchter, A. S.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hardin, D.; Hook, I. M.; Howell, D. A.; Irwin, M. J.; Kim, A. G.; Kim, M. Y.; Knop, R. A.; Lee, J. C.; Perlmutter, S.; Ruiz-Lapuente, P.; Schahmaneche, K.; Schaefer, B.; Walton, N. A.

    2002-05-28

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  9. The distant Type Ia supernova rate

    CERN Document Server

    Pain, R; Sullivan, M; Ellis, Richard S; Aldering, G; Astier, Pierre; Duestua, S E; Fruchter, A S; Goldhaber, Gerson; Goobar, A; Groom, D E; Hardin, D; Hook, I M; Howell, D A; Irwin, M J; Kim, A G; Kim, M Y; Knop, R A; Lee, J C; Lidman, C E; McMahon, R G; Nugent, P; Panagia, N; Pennypacker, C R; Perlmutter, S; Ruiz-Lapuente, P; Schahmaneche, K; Schaefer, B; Walton, N A

    2001-01-01

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially-flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean redshift $z\\simeq0.55$ of $1.53 {^{+0.28}_{-0.25}} {^{+0.32}_{-0.31}} 10^{-4} h^3 {\\rm Mpc}^{-3} {\\rm yr}^{-1}$ or $0.58 {^{+0.10}_{-0.09}} {^{+0.10}_{-0.09}} h^2 {\\rm SNu}$ (1 SNu = 1 supernova per century per $10^{10}$\\Lbsun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  10. Gravitational wave triggered searches for failed supernovae

    Science.gov (United States)

    Annis, James; Dark Energy Survey Collaboration

    2016-03-01

    Stellar core collapses occur to all stars of sufficiently high mass and often result in supernovae. A small fraction of supergiant stars, however, are thought to collapse directly into black holes without producing supernovae. A survey of such ``failed'' supernovae would require monitoring millions of supergiants for several years. That is very challenging even for current surveys. With the start of the Advanced LIGO science run, we investigate the possibility of detecting failed supernovae by looking for missing supergiants associated with gravitational wave triggers. We use the Dark Energy Camera (DECam). Our project is a joint effort between the community and the Dark Energy Survey (DES) collaboration. In this talk we report on our ongoing efforts and discuss prospects for future searches.

  11. Supernovae, dark energy and the accelerating universe

    CERN Document Server

    Perlmutter, Saul

    1999-01-01

    Based on an analysis of 42 high-redshift supernovae discovered by the supernovae cosmology project, we have found evidence for a positive cosmological constant, Lambda, and hence an accelerating universe. In particular, the data are strongly inconsistent with a Lambda=0 flat cosmology, the simplest inflationary universe model. The size of our supernova sample allows us to perform a variety of statistical tests to check for possible systematic errors and biases. We will discuss results of these and other studies and the ongoing hunt for further loopholes to evade the apparent consequences of the measurements. We will present further work that begins to constrain the alternative physics theories of "dark energy" that have been proposed to explain these results. Finally, we propose a new concept for a definitive supernova measurement of the cosmological parameters.

  12. Supernova Classification Using Swift UVOT Photometry

    Science.gov (United States)

    Smith, Madison; Brown, Peter J.

    2017-01-01

    With the great influx of supernova discoveries over the past few years, the observation time needed to acquire the spectroscopic data needed to classify supernova by type has become unobtainable. Instead, using the photometry of supernovae could greatly reduce the amount of time between discovery and classification. For this project we looked at the relationship between colors and supernova types through machine learning packages in Python. Using data from the Swift Ultraviolet/Optical Telescope (UVOT), each photometric point was assigned values corresponding to colors, absolute magnitudes, and the relative times from the peak brightness in several filters. These values were fed into three classifying methods, the nearest neighbors, decision tree, and random forest methods. We will discuss the success of these classification systems, the optimal filters for photometric classification, and ways to improve the classification.

  13. Background Study on Supernova Relic Neutrinos Search in SuperK-Gd

    CERN Document Server

    Zhang, Yang

    2016-01-01

    The detection of supernova relic neutrinos could provide precious information on the evolution of the universe, the formation of stars, the mechanism of supernova bursts and the related neutrino physics. Many experiments, such as Kamland, Borexino, Sudbury Neutrino Observatory and Super-Kamiokande have conducted searches for the supernova relic neutrinos. However, no supernova relic neutrino signal has been observed until now. This paper reports the background study on the supernova relic neutrinos search for the future neutrino experiment in SuperK-Gd project. The expected event rate for various background sources and supernova relic neutrino models are calculated, respectively.

  14. Fukushima to receive Smith Medal

    Science.gov (United States)

    The 1990 Waldo E. Smith Medal for extraordinary service to geophysics will be given to Naoshi Fukushima, who earned an international reputation for his pioneering work in geomagnetic disturbance and ionospheric electric currents. Now retired from the University of Tokyo, Japan, Fukushima is being cited for his public service to international geophysics, and, in particular, his contributions to the International Association of Geomagnetism and Aeronomy, of which he was Secretary General from September 1975 to August 1983.The Smith Medal will be presented as part of the AGU Fall Meeting Honors Night festivities, Wednesday, December 5, in San Francisco, Calif. Three James B. Macelwane Medals, the John Adam Fleming Medal, and the Maurice Ewing Medal will also be presented (see Eos, February 20, 1990, p. 294).

  15. A kinetic and Kinematic analysis in two assessment situation with bench press. Free Weight vs Smith Machine. Project pilot. ANÁLISIS CINÉTICO Y CINEMÁTICO DEL PRESS DE BANCA EN DOS SITUACIONES DE EVALUACIÓN: PRESS BANCA LIBRE VS PRESS BANCA MÁQUINA SMITH. PROYECTO PILOTO [A kinetic and Kinematic analysis in two assessment situation with bench press. Free Weight vs Smith Mach

    Directory of Open Access Journals (Sweden)

    J. M. Monje

    2012-06-01

    Full Text Available This pilot study examines the most relevant kinetic and kinematics variables in two bench press exercises; Smith Machine (PMS vs. free weights (PBL. Two trained subjects participated in the research following informed consent. To determine the maximum load (1-RM, two incremental protocols were used for PMS and PBL. Subject 1 (S-1 produced force values of 770N and 837N, peak force of 28ms and 12ms, in PBL and PMS respectively. Values for subject 2 (S-2 were 693N and 849N, PMF of 60ms and 66ms for PBL and PMS respectively. Detailed analyses of the following variables were performed; velocity curves for each load, the “sticking period”, the distances of grip width, and changes in bar inclination during the ascent phase of the lift were examined. The key findings of this research, and the basis for future research demonstrate that PBL is recommended as a training exercise, while more reliable information regarding force variables can be attained through using PMS in measurement sessions. Key Words: Bench Press, smith machine, free weight, strength assessment, upper limb. En este estudio piloto se analizan algunas de las variables cinéticas y cinemáticas que pueden afectar a la situación de ejecución/evaluación del Press de Banca, en máquina Smith (PMS vs con barra y discos (PBL. Dos sujetos entrenados participaron en esta investigación habiendo sido informados previamente de la finalidad de la misma. En dos momentos se llevó a cabo un protocolo incremental de cargas hasta alcanzar su máximo peso a desplazar en una repetición (1-RM, uno para el PMS y otro para el PBL. El Sujeto 1 (S-1 manifestó valores de fuerza de 770 y 837 N, en PBL y PMS, alcanzando este pico máximo de fuerza (PMF a los 28 y 12 ms, respectivamente. En el caso del Sujeto 2 (S-2, los valores de PMF fueron de 693 y 849 N, empleando un tiempo en alcanzar estos PMF fue de 60 y 66 ms, en PBL y PMS, respectivamente. Se realizó un análisis detallado de las curvas de 

  16. A Precision Photometric Comparison between SDSS-II and CSP Type Ia Supernova Data

    DEFF Research Database (Denmark)

    Mosher, J.; Sako, M.; Corlies, L.

    2012-01-01

    Consistency between Carnegie Supernova Project (CSP) and SDSS-II Supernova Survey ugri measurements has been evaluated by comparing Sloan Digital Sky Survey (SDSS) and CSP photometry for nine spectroscopically confirmed Type Ia supernova observed contemporaneously by both programs. The CSP data w...

  17. A Precision Photometric Comparison between SDSS-II and CSP Type Ia Supernova Data

    DEFF Research Database (Denmark)

    Mosher, J.; Sako, M.; Corlies, L.;

    2012-01-01

    Consistency between Carnegie Supernova Project (CSP) and SDSS-II Supernova Survey ugri measurements has been evaluated by comparing Sloan Digital Sky Survey (SDSS) and CSP photometry for nine spectroscopically confirmed Type Ia supernova observed contemporaneously by both programs. The CSP data...

  18. Adam Smith y el derecho

    Directory of Open Access Journals (Sweden)

    Federico Escobar Córdoba

    2004-12-01

    Full Text Available Este artículo destaca el análisis jurídico en la obra de Adam Smith y su enriquecedor método de estudiar el derecho, particularmente en sus Lecciones de jurisprudencia. Esboza el contexto jurídico de las Lecciones e informa sobre su público original. Luego, describe la presencia del derecho romano en esa obra, deteniéndose en dos aspectos que los editores de la Edición Glasgow señalaron como errores o imprecisiones. El artículo analiza estos aspectos, ofrece posibles explicaciones alternativas que, a la vez, resaltan la complejidad del pensamiento jurídico de Smith. Finalmente, identifica tres niveles de análisis, empleados por Smith en las Lecciones, cuya interacción sería una contribución importante a la dogmática jurídica contemporánea.

  19. Supernovae neutrino pasta interaction

    Science.gov (United States)

    Lin, Zidu; Horowitz, Charles; Caplan, Matthew; Berry, Donald; Roberts, Luke

    2017-01-01

    In core-collapse supernovae, the neutron rich matter is believed to have complex structures, such as spherical, slablike, and rodlike shapes. They are collectively called ``nuclear pasta''. Supernovae neutrinos may scatter coherently on the ``nuclear pasta'' since the wavelength of the supernovae neutrinos are comparable to the nuclear pasta scale. Consequently, the neutrino pasta scattering is important to understand the neutrino opacity in the supernovae. In this work we simulated the ``nuclear pasta'' at different temperatures and densities using our semi-classical molecular dynamics and calculated the corresponding static structure factor that describes ν-pasta scattering. We found the neutrino opacities are greatly modified when the ``pasta'' exist and may have influence on the supernovae neutrino flux and average energy. Our neutrino-pasta scattering effect can finally be involved in the current supernovae simulations and we present preliminary proto neutron star cooling simulations including our pasta opacities.

  20. Supernova Neutrino Detection

    Energy Technology Data Exchange (ETDEWEB)

    Gil-Botella, Ines, E-mail: ines.gil@ciemat.es [CIEMAT, Basic Research Department, Avenida Complutense, 22, 28040 Madrid (Spain)

    2011-07-25

    The neutrino burst from a core collapse supernova can provide information about the explosion mechanism and the mechanisms of proto neutron star cooling but also about the intrinsic properties of the neutrino such as flavor oscillations. One important question is to understand to which extend can the supernova and the neutrino physics be decoupled in the observation of a single supernova. The possibility to probe the neutrino mixing angle {theta}{sub 13} and the type of mass hierarchy from the detection of supernova neutrinos with liquid argon detectors is discussed in this paper. Moreover, a quantitatively study about the possibility to constrain the supernova parameters is presented. A very massive liquid argon detector ({approx} 100 kton) is needed to perform accurate measurements of these parameters. Finally the possible detection of the diffuse supernova neutrino background in liquid argon detectors is also described.

  1. The historical supernovae

    CERN Document Server

    Clark, David H

    1977-01-01

    The Historical Supernovae is an interdisciplinary study of the historical records of supernova. This book is composed of 12 chapters that particularly highlight the history of the Far East. The opening chapter briefly describes the features of nova and supernova, stars which spontaneously explode with a spectacular and rapid increase in brightness. The succeeding chapter deals with the search for the historical records of supernova from Medieval European monastic chronicles, Arabic chronicles, astrological works etc., post renaissance European scientific writings, and Far Eastern histories and

  2. Atomic and molecular supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.

    1997-12-01

    Atomic and molecular physics of supernovae is discussed with an emphasis on the importance of detailed treatments of the critical atomic and molecular processes with the best available atomic and molecular data. The observations of molecules in SN 1987A are interpreted through a combination of spectral and chemical modelings, leading to strong constraints on the mixing and nucleosynthesis of the supernova. The non-equilibrium chemistry is used to argue that carbon dust can form in the oxygen-rich clumps where the efficient molecular cooling makes the nucleation of dust grains possible. For Type Ia supernovae, the analyses of their nebular spectra lead to strong constraints on the supernova explosion models.

  3. The SILCC (SImulating the LifeCycle of molecular Clouds) project - II. Dynamical evolution of the supernova-driven ISM and the launching of outflows

    Science.gov (United States)

    Girichidis, Philipp; Walch, Stefanie; Naab, Thorsten; Gatto, Andrea; Wünsch, Richard; Glover, Simon C. O.; Klessen, Ralf S.; Clark, Paul C.; Peters, Thomas; Derigs, Dominik; Baczynski, Christian

    2016-03-01

    The SILCC project (SImulating the Life-Cycle of molecular Clouds) aims at a more self-consistent understanding of the interstellar medium (ISM) on small scales and its link to galaxy evolution. We present three-dimensional (magneto)hydrodynamic simulations of the ISM in a vertically stratified box including self-gravity, an external potential due to the stellar component of the galactic disc, and stellar feedback in the form of an interstellar radiation field and supernovae (SNe). The cooling of the gas is based on a chemical network that follows the abundances of H+, H, H2, C+, and CO and takes shielding into account consistently. We vary the SN feedback by comparing different SN rates, clustering and different positioning, in particular SNe in density peaks and at random positions, which has a major impact on the dynamics. Only for random SN positions the energy is injected in sufficiently low-density environments to reduce energy losses and enhance the effective kinetic coupling of the SNe with the gas. This leads to more realistic velocity dispersions (σ _H I≈ 0.8σ _{300{-}8000 K}˜ 10-20 km s^{-1}, σ _H α ≈ 0.6σ _{8000-3× 10^5 K}˜ 20-30 km s^{-1}), and strong outflows with mass loading factors (ratio of outflow to star formation rate) of up to 10 even for solar neighbourhood conditions. Clustered SNe abet the onset of outflows compared to individual SNe but do not influence the net outflow rate. The outflows do not contain any molecular gas and are mainly composed of atomic hydrogen. The bulk of the outflowing mass is dense (ρ ˜ 10-25-10-24 g cm-3) and slow (v ˜ 20-40 km s-1) but there is a high-velocity tail of up to v ˜ 500 km s-1 with ρ ˜ 10-28-10-27 g cm-3.

  4. An interview with Jim Smith.

    Science.gov (United States)

    Maartens, Aidan

    2017-08-01

    Jim Smith is Director of Science at the Wellcome Trust and a group leader at the Francis Crick Institute, where he was formerly Director of Research. A Fellow of both the Royal Society and the Academy of Medical Sciences, he was knighted for his services to medical research and science education in 2016. His lab works on mesoderm induction in the early vertebrate embryo. We met Jim in the Crick to hear about his life in science, his visions for the Crick and the Wellcome Trust, and his advice for early career scientists. © 2017. Published by The Company of Biologists Ltd.

  5. Smith, Malthus and Recent Evidence in Global Population Dynamics

    OpenAIRE

    Xiao Jiang; Luis Villanueva

    2015-01-01

    In conventional economic theories, population is determined outside of the economic system. However, classical political economists such as Adam Smith and Thomas Malthus have long argued for the endogenous determination of population, hence establishing a connection between economics and demography. Foley (2000) used empirically established global per capita output-fertility schedule based on the 1960-1992 Extended Penn World Tables to project the population stabilizing level of world per cap...

  6. Electronic applications of the Smith chart

    CERN Document Server

    Smith, Phillip

    1995-01-01

    The legendary Smith chart inventor's classic reference book describes how the chart is used for designing lumped element and transmission line circuits. Provides tutorial material on transmission line theory and behavior, circuit representation on the chart, matching networks, network transformations and broadband matching. Includes a new chapter with examples designs and description of the winSMITH software accessory. Many computational instruments have succumbed to the power of the digital computer. This is not the case with the Smith Chart. A testament to Phil's genius is that his Smith Cha

  7. The Frequency of Supernovae in the Early Universe

    Science.gov (United States)

    Melinder, Jens

    Supernovae are cosmic explosions of cataclysmic proportion that signify the death of a star. While being interesting phenomena in their own right, their brightness also make them excellent probes of the early universe. Depending on the type of the progenitor star and the origin of the explosion different subjects can be investigated. In this dissertation the work I have done on the detection, characterisation and rate measurements of supernovae in the Stockholm VIMOS Supernova Search is presented. We have discovered 16 supernovae that exploded billions of years ago (or, equivalently, at high redshift, z). The observed brightness and colour evolution have been used to classify the supernovae into either thermonuclear (type Ia) or core collapse (type II) supernovae. The accuracy of the classification code is high, only about 5% of the supernovae are mistyped, similar to other codes of the same kind. By comparing the observed frequency of supernovae to simulations the underlying supernova rate at these high redshifts have been measured. The main result reported in this thesis is that the core collapse supernova rate at high redshift matches the rates estimated from looking at the star formation history of the universe, and agree well with previous studies. The rate of Ia supernovae at high redshift have been investigated by several projects, our results show a somewhat higher rate of Ia supernovae than expected. Proper estimates of the systematic errors of rate measurements are found to be very important. Furthermore, by using novel techniques for reducing and stacking images, we have obtained a galaxy sample containing approximately 50,000 galaxies. Photometric redshifts have been obtained for most of the galaxies, the resulting accuracy below z=1 is on the order of 10%. The galaxy sample has also been used to find high redshift sources, so called Lyman Break Galaxies, at z=3-5.

  8. Neutrinos from Supernovae

    CERN Document Server

    Choubey, S; Choubey, Sandhya; Kar, Kamales

    2002-01-01

    In this review, the effect of flavor oscillations on the neutrinos released during supernova explosion after core collapse is described. In some scenarios there are large enhancement of the number of events compared to the no oscillation case. Various other features associated with supernova neutrinos are also discussed.

  9. Molecules in supernova ejecta

    CERN Document Server

    Cherchneff, Isabelle

    2011-01-01

    The first molecules detected at infrared wavelengths in the ejecta of a Type II supernova, namely SN1987A, consisted of CO and SiO. Since then, confirmation of the formation of these two species in several other supernovae a few hundred days after explosion has been obtained. However, supernova environments appear to hamper the synthesis of large, complex species due to the lack of microscopically-mixed hydrogen deep in supernova cores. Because these environments also form carbon and silicate dust, it is of importance to understand the role played by molecules in the depletion of elements and how chemical species get incorporated into dust grains. In the present paper, we review our current knowledge of the molecular component of supernova ejecta, and present new trends and results on the synthesis of molecules in these harsh, explosive events.

  10. Spectroscopy of superluminous supernova host galaxies

    DEFF Research Database (Denmark)

    Leloudas, G.; Kruehler, T.; Schulze, S

    2015-01-01

    Superluminous supernovae (SLSNe) are very bright explosions that were only discovered recently and that show a preference for occurring in faint dwarf galaxies. Understanding why stellar evolution yields different types of stellar explosions in these environments is fundamental in order to both...... uncover the elusive progenitors of SLSNe and to study star formation in dwarf galaxies. In this paper, we present the first results of our project to study SUperluminous Supernova Host galaxIES, focusing on the sample for which we have obtained spectroscopy. We show that SLSNe-I and SLSNe-R (hydrogen...

  11. Guide to the Logan Pearsall Smith Collection.

    Science.gov (United States)

    Pettit, Katherine Denshaw

    A guide to the Logan Pearsall Smith Collection at Trinity University Elizabeth Coates Maddux Library in San Antonio, Texas provides a descriptive overview of the collected works of this renowned epigrammatist, critic, essayist, biographer, and authority on the English language. The guide includes a brief biography of Smith (1865-1946), detailed…

  12. Bringing Sally Smith's Vision to Manayunk

    Science.gov (United States)

    Ford, Jackie

    2010-01-01

    In this article, the author narrates her application of what she learned from her internship at Sally Smith's Lab School of Washington to her new school and shares the favorable impact it had brought on her teaching career. The author shares her first exposure to the powerful effects of Smith's "Live It, Learn It" methodology as she…

  13. 33 CFR 117.841 - Smith Creek.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Smith Creek. 117.841 Section 117.841 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements North Carolina § 117.841 Smith Creek. The draw of the...

  14. Piketty en Smith : een bijzonder span?

    NARCIS (Netherlands)

    Gribnau, J.L.M.

    2015-01-01

    Piketty belicht economische, politieke, ethische en sociale aspecten van belastingen. Sloterdijk betoogde al eerder dat belastingen een moreel verschijnsel zijn. Adam Smith heeft een al even breed perspectief op belastingen. Piketty en Smith delen de idee dat belastingen vanuit verschillende invalsh

  15. The Treatment of Smith's Invisible Hand

    Science.gov (United States)

    Wight, Jonathan B.

    2007-01-01

    Adam Smith used the metaphor of an invisible hand to represent the instincts of human nature that direct behavior. Moderated by self-control and guided by proper institutional incentives, actions grounded in instincts can be shown to generate a beneficial social order even if not intended. Smith's concept, however, has been diluted and distorted…

  16. Turgot en Smith; een paar apart

    NARCIS (Netherlands)

    Hoyng, A.C.

    2011-01-01

    Anne-Claire Hoyng deed onderzoek naar het boek The Wealth of Nations van Adam Smith (1723-1790). Ze concludeert dat Smith voor het schrijven van zijn boek een werk van de Fransman Anne-Robert Jacques Turgot (1727-1781) als inspiratiebron gebruikte (Réflexions sur la Formation et la distribution des

  17. Adam Smith and the Rhetoric of Style.

    Science.gov (United States)

    Moran, Michael G.

    Historians of rhetoric have generally accepted the view that Adam Smith rejected the principles of classical rhetoric. However, while there can be no doubt that Smith greatly truncated the five classical arts of rhetoric (invention, arrangement, style, memory, and delivery) by reducing his concerns largely to style and arrangement, he did not…

  18. Turgot en Smith; een paar apart

    NARCIS (Netherlands)

    Hoyng, A.C.

    2011-01-01

    Anne-Claire Hoyng deed onderzoek naar het boek The Wealth of Nations van Adam Smith (1723-1790). Ze concludeert dat Smith voor het schrijven van zijn boek een werk van de Fransman Anne-Robert Jacques Turgot (1727-1781) als inspiratiebron gebruikte (Réflexions sur la Formation et la distribution des

  19. Environmental assessment: Deaf Smith County site, Texas

    Energy Technology Data Exchange (ETDEWEB)

    1986-05-01

    In February 1983, the US Department of Energy (DOE) identified a location in Deaf Smith County, Texas, as one of nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Deaf Smith County site and the eight other potentially sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. The Deaf Smith County site is in the Permian Basin, which is one of five distinct geohydrologic settings considered for the first repository. On the basis of the evaluations reported in this EA, the DOE has found that the Deaf Smith County site is not disqualified under the guidelines. On the basis of these findings, the DOE is nominating the Deaf Smith County site as one of the five sites suitable for characterization. 591 refs., 147 figs., 173 tabs.

  20. Smith Newton Vehicle Performance Evaluation - Gen 2 - Cumulative (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-08-01

    The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory is evaluating and documenting the performance of electric and plug-in hybrid electric drive systems in medium-duty trucks across the nation. U.S. companies participating in this evaluation project received funding from the American Recovery and Reinvestment Act to cover part of the cost of purchasing these vehicles. Through this project, Smith Electric Vehicles is building and deploying 500 all-electric medium-duty trucks that will be deployed by a variety of companies in diverse climates across the country.

  1. Smith Newton Vehicle Performance Evaluation - 1st Quarter 2014 (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-04-01

    The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory is evaluating and documenting the performance of electric and plug-in hybrid electric drive systems in medium-duty trucks across the nation. U.S. companies participating in this evaluation project received funding from the American Recovery and Reinvestment Act to cover part of the cost of purchasing these vehicles. Through this project, Smith Electric Vehicles is building and deploying 500 all-electric medium-duty trucks that will be deployed by a variety of companies in diverse climates across the country.

  2. Smith Newton Vehicle Performance Evaluation - Gen2 - 2013 (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-04-01

    The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory is evaluating and documenting the performance of electric and plug-in hybrid electric drive systems in medium-duty trucks across the nation. U.S. companies participating in this evaluation project received funding from the American Recovery and Reinvestment Act to cover part of the cost of purchasing these vehicles. Through this project, Smith Electric Vehicles is building and deploying 500 all-electric medium-duty trucks that will be deployed by a variety of companies in diverse climates across the country.

  3. Automated search for supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Kare, J.T.

    1984-11-15

    This thesis describes the design, development, and testing of a search system for supernovae, based on the use of current computer and detector technology. This search uses a computer-controlled telescope and charge coupled device (CCD) detector to collect images of hundreds of galaxies per night of observation, and a dedicated minicomputer to process these images in real time. The system is now collecting test images of up to several hundred fields per night, with a sensitivity corresponding to a limiting magnitude (visual) of 17. At full speed and sensitivity, the search will examine some 6000 galaxies every three nights, with a limiting magnitude of 18 or fainter, yielding roughly two supernovae per week (assuming one supernova per galaxy per 50 years) at 5 to 50 percent of maximum light. An additional 500 nearby galaxies will be searched every night, to locate about 10 supernovae per year at one or two percent of maximum light, within hours of the initial explosion.

  4. Supernova electron capture rates

    CERN Document Server

    Martínez-Pinedo, G

    1999-01-01

    We have calculated the Gamow-Teller strength distributions for the ground states and low lying states of several nuclei that play an important role in the precollapse evolution of supernova. The calculations reproduce the experimental GT distributions nicely. The GT distribution are used to calculate electron capture rates for typical presupernova conditions. The computed rates are noticeably smaller than the presently adopted rates. The possible implications for the supernova evolution are discussed.

  5. Neal Smith monthly activities reports FY 2005

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2005 fiscal year. Included in the document are...

  6. Neal Smith monthly activities reports FY 2003

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2003 fiscal year. Included in the document are...

  7. Neal Smith monthly activities reports FY 2002

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2002 fiscal year. Included in the document are...

  8. Neal Smith monthly activities reports FY 2001

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2001 fiscal year. Included in the document are...

  9. Neal Smith monthly activities reports FY 2007

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2007 fiscal year. Included in the document are...

  10. Neal Smith monthly activities reports FY 2009

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2009 fiscal year. Included in the document are...

  11. Neal Smith monthly activities reports FY 2008

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2008 fiscal year. Included in the document are...

  12. Neal Smith monthly activities reports FY 2006

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2006 fiscal year. Included in the document are...

  13. Neal Smith monthly activities reports FY 2004

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2004 fiscal year. Included in the document are...

  14. Environmental assessment: Deaf Smith County site, Texas

    Energy Technology Data Exchange (ETDEWEB)

    1986-05-01

    In February 1983, the US Department of Energy (DOE) identified a location in Deaf Smith County, Texas, as one of the nine potentially acceptable sites for mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Deaf Smith County site and eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. The Deaf Smith County site is in the Permian Basin, which is one of five distinct geohydrologic settings considered for the first repository. On the basis of the evaluations reported in this EA, the DOE has found that the Deaf Smith County site is not disqualified under the guidelines.

  15. Neal Smith monthly activities reports FY 2010

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These monthly reports detail activities on Neal Smith National Wildlife Refuge in Prairie City, Iowa during the 2010 fiscal year. Included in the document are...

  16. Environmental assessment, Deaf Smith County site, Texas

    Energy Technology Data Exchange (ETDEWEB)

    1986-05-01

    The Nuclear Waste Policy Act of 1982 (42 USC sections 10101-10226) requires the environmental assessment of a proposed site to include a statement of the basis for nominating a site as suitable for characterization. Volume 2 provides a detailed statement evaluating the site suitability of the Deaf Smith County Site under DOE siting guidelines, as well as a comparison of the Deaf Smith County Site to the other sites under consideration. The evaluation of the Deaf Smith County Site is based on the impacts associated with the reference repository design, but the evaluation will not change if based on the Mission Plan repository concept. The second part of this document compares the Deaf Smith County Site to Davis Canyon, Hanford, Richton Dome and Yucca Mountain. This comparison is required under DOE guidelines and is not intended to directly support subsequent recommendation of three sites for characterization as candidate sites. 259 refs., 29 figs., 66 refs. (MHB)

  17. Adam Smith: Anthropology and Moral Philosophy

    OpenAIRE

    Lázaro-Cantero, R. (Raquel)

    2010-01-01

    Adam Smith was a moral philosopher. His economic and legal thought can't be separated from his moral psychology which frames his anthropological and social proposal. Experimental Newtonian methodology and Hume's empirism feed his approximation to the reality of human being. In this new context the traditional categories of society are defined and combined in a new way. In this paper I try to argue that the assumed optimism which sometimes is attributed to Smith about the proper functioning of...

  18. Gene Smith and Tibetology in the West

    Institute of Scientific and Technical Information of China (English)

    BAI Macuo

    2014-01-01

    Gene Smith , a famous Tibetologist and the founder of the Tibetan Buddhist Resource Center ( TBRC) , passed into nirvana on December 16th 2010.This sad news shocked the circle of in-ternational Tibetologists .Everyone felt a sense of regret and sadness . On February 12th 2011, TBRC organized a seminar together with a memori-al for Gene Smith.More than 100 Tibetologists worldwide concentrated in New York to take part in this activity .

  19. Marshall-Smith syndrome: case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Yong; Lee, Shi Kyung; Cho, In Chul; Han, Chun Hwan [Kangnam General Hosital Public Corporation, Seoul (Korea, Republic of)

    2002-12-01

    Marshall-Smith syndrome is a rare disease, with about 29 cases reported to date. It is characterized by accelerated bony growth and maturation, phalangeal abnormalities (wide middle and narrow distal phalanges), unusual facial features (prominent eyes, bluish sclerae, coarse eyebrows, an upturned nose, hypoplastic facial bones, and shallow orbits), failure to thrive, respiratory difficulties, and psychomotor retardation. This report of the radiologic findings of Marshall-Smith syndrome is, as for as we know, the first to be published in Korea.

  20. Cosmic Supernova Rate History and Type Ia Supernova Progenitors

    OpenAIRE

    Kobayashi, Chiaki; Nomoto, Ken'ichi; Tsujimoto, Takuji

    2001-01-01

    Adopting a single degenerate scenario for Type Ia supernova progenitors with the metallicity effect, we make a prediction of the cosmic supernova rate history as a composite of the supernova rates in spiral and elliptical galaxies, and compare with the recent observational data up to z ~ 0.55.

  1. Modeling Core Collapse Supernovae

    Science.gov (United States)

    Mezzacappa, Anthony

    2017-01-01

    Core collapse supernovae, or the death throes of massive stars, are general relativistic, neutrino-magneto-hydrodynamic events. The core collapse supernova mechanism is still not in hand, though key components have been illuminated, and the potential for multiple mechanisms for different progenitors exists. Core collapse supernovae are the single most important source of elements in the Universe, and serve other critical roles in galactic chemical and thermal evolution, the birth of neutron stars, pulsars, and stellar mass black holes, the production of a subclass of gamma-ray bursts, and as potential cosmic laboratories for fundamental nuclear and particle physics. Given this, the so called ``supernova problem'' is one of the most important unsolved problems in astrophysics. It has been fifty years since the first numerical simulations of core collapse supernovae were performed. Progress in the past decade, and especially within the past five years, has been exponential, yet much work remains. Spherically symmetric simulations over nearly four decades laid the foundation for this progress. Two-dimensional modeling that assumes axial symmetry is maturing. And three-dimensional modeling, while in its infancy, has begun in earnest. I will present some of the recent work from the ``Oak Ridge'' group, and will discuss this work in the context of the broader work by other researchers in the field. I will then point to future requirements and challenges. Connections with other experimental, observational, and theoretical efforts will be discussed, as well.

  2. The Most Luminous Supernovae

    Science.gov (United States)

    Sukhbold, Tuguldur; Woosley, S. E.

    2016-04-01

    Recent observations have revealed a stunning diversity of extremely luminous supernovae, seemingly increasing in radiant energy without bound. We consider simple approximate limits for what existing models can provide for the peak luminosity and total radiated energy for non-relativistic, isotropic stellar explosions. The brightest possible supernova is a Type I explosion powered by a sub-millisecond magnetar with field strength B ∼ few × {10}13 G. In extreme cases, such models might reach a peak luminosity of 2× {10}46 {erg} {{{s}}}-1 and radiate a total energy of up to 4× {10}52 {erg}. Other less luminous models are also explored, including prompt hyper-energetic explosions in red supergiants, pulsational-pair instability supernovae, pair-instability supernovae, and colliding shells. Approximate analytic expressions and limits are given for each case. Excluding magnetars, the peak luminosity is near 3× {10}44 {erg} {{{s}}}-1 for the brightest models and the corresponding limit on total radiated energy is 3× {10}51 {erg}. Barring new physics, supernovae with a light output over 3× {10}51 erg must be rotationally powered, either during the explosion itself or after, the most obvious candidate being a rapidly rotating magnetar. A magnetar-based model for the recent transient event, ASASSN-15lh is presented that strains, but does not exceed the limits of what the model can provide.

  3. Runaway Stars in Supernova Remnants

    Science.gov (United States)

    Pannicke, Anna; Neuhaeuser, Ralph; Dinçel, Baha

    2016-07-01

    Half of all stars and in particular 70 % of the massive stars are a part of a multiple system. A possible development for the system after the core collapse supernova (SN) of the more massive component is as follows: The binary is disrupted by the SN. The formed neutron star is ejected by the SN kick whereas the companion star either remains within the system and is gravitationally bounded to the neutron star, or is ejected with a spatial velocity comparable to its former orbital velocity (up to 500 km/s). Such stars with a large peculiar space velocity are called runaway stars. We present our observational results of the supernova remnants (SNRs) G184.6-5.8, G74.0-8.5 and G119.5+10.2. The focus of this project lies on the detection of low mass runaway stars. We analyze the spectra of a number of candidates and discuss their possibility of being the former companions of the SN progenitor stars. The spectra were obtained with INT in Tenerife, Calar Alto Astronomical Observatory and the University Observatory Jena. Also we investigate the field stars in the neighborhood of the SNRs G74.0-8.5 and G119.5+10.2 and calculate more precise distances for these SNRs.

  4. Nearby supernova factory announces 34 supernovae in one year'; best Rookie year ever for supernova search

    CERN Multimedia

    2003-01-01

    The Nearby Supernova Factory (SNfactory), an international collaboration based at Lawrence Berkeley National Laboratory, announced that it had discovered 34 supernovae during the first year of the prototype system's operation (2 pages).

  5. Evidence of Historical Supernovae in Ice Cores

    Science.gov (United States)

    Young, Donna

    2011-05-01

    Within the framework of the U.S. Greenland Ice Core Science Project (GISP2), an ice core, known as the GISP H-Core, was collected in June, 1992 adjacent to the GISP2 summit drill site. The project scientists, Gisela A.M. Dreschhoff and Edward J. Zeller, were interested in dating solar proton events with volcanic eruptions. The GISP2-H 122-meter firn and ice core is a record of 415 years of liquid electrical conductivity (LEC) and nitrate concentrations, spanning the years 1992 at the surface through 1577 at the bottom. At the National Ice Core Laboratory in Denver, Colorado, the core (beneath the 12-meter firn) was sliced into 1.5 cm sections and analyzed. The resulting data set consisted of 7,776 individual analyses. The ultrahigh resolution sampling technique resulted in a time resolution of one week near the surface and one month at depth. The liquid electrical conductivity (LEC) sequence contains signals from a number of known volcanic eruptions and provides a dating system at specific locations along the core. The terrestrial and solar background nitrate records show seasonal and annual variations, respectively. However, major nitrate anomalies within the record do not correspond to any known terrestrial or solar events. There is evidence that these nitrate anomalies could be a record of supernovae events. Cosmic X-rays ionize atmospheric nitrogen, producing excess nitrate that is then deposited in the Polar Regions. The GISP2-H ice core has revealed nitrate anomalies at the times of the Tycho and Kepler supernovae. The Cassiopeia A supernova event may be documented in the core as well. We have developed a classroom activity for high school and college students, in which they examine several lines of evidence in the Greenland ice core, discriminating among nearby and mid-latitude volcanic activity, solar proton events, and supernovae. Students infer the date of the Cassiopeia A supernova.

  6. Cosmology with Superluminous Supernovae

    CERN Document Server

    Scovacricchi, Dario; Bacon, David; Sullivan, Mark; Prajs, Szymon

    2015-01-01

    We predict cosmological constraints for forthcoming surveys using Superluminous Supernovae (SLSNe) as standardisable candles. Due to their high peak luminosity, these events can be observed to high redshift (z~3), opening up new possibilities to probe the Universe in the deceleration epoch. We describe our methodology for creating mock Hubble diagrams for the Dark Energy Survey (DES), the "Search Using DECam for Superluminous Supernovae" (SUDSS) and a sample of SLSNe possible from the Large Synoptic Survey Telescope (LSST), exploring a range of standardisation values for SLSNe. We include uncertainties due to gravitational lensing and marginalise over possible uncertainties in the magnitude scale of the observations (e.g. uncertain absolute peak magnitude, calibration errors). We find that the addition of only ~100 SLSNe from SUDSS to 3800 Type Ia Supernovae (SNe Ia) from DES can improve the constraints on w and Omega_m by at least 20% (assuming a flat wCDM universe). Moreover, the combination of DES SNe Ia a...

  7. Physics of supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Woosley, S.E.; Weaver, T.A.

    1985-12-13

    Presupernova models of massive stars are presented and their explosion by ''delayed neutrino transport'' examined. A new form of long duration Type II supernova model is also explored based upon repeated encounter with the electron-positron pair instability in stars heavier than about 60 Msub solar. Carbon deflagration in white dwarfs is discussed as the probable explanation of Type I supernovae and special attention is paid to the physical processes whereby a nuclear flame propagates through degenerate carbon. 89 refs., 12 figs.

  8. Demonstrating Supernova Remnant Evolution

    Science.gov (United States)

    Leahy, Denis A.; Williams, Jacqueline

    2017-01-01

    We have created a software tool to calculate at display supernova remnant evolution which includes all stages from early ejecta dominated phase to late-time merging with the interstellar medium. The software was created using Python, and can be distributed as Python code, or as an executable file. The purpose of the software is to demonstrate the different phases and transitions that a supernova remnant undergoes, and will be used in upper level undergraduate astrophysics courses as a teaching tool. The usage of the software and its graphical user interface will be demonstrated.

  9. BVRI Photometry of Supernovae

    OpenAIRE

    Ho, Wynn C. G.; Van Dyk, Schuyler D.; Peng, Chien Y.; Filippenko, Alexei V.; Leonard, Douglas C.; Matheson, Thomas; Treffers, Richard R.; Richmond, Michael W.

    2001-01-01

    We present optical photometry of one Type IIn supernova (1994Y) and nine Type Ia supernovae (1993Y, 1993Z, 1993ae, 1994B, 1994C, 1994M, 1994Q, 1994ae, and 1995D). SN 1993Y and SN 1993Z appear to be normal SN Ia events with similar rates of decline, but we do not have data near maximum brightness. The colors of SN 1994C suggest that it suffers from significant reddening or is intrinsically red. The light curves of SN 1994Y are complicated; they show a slow rise and gradual decline near maximum...

  10. The Devil in Mr. Smith: A Conversation with Jonathan Z. Smith

    Science.gov (United States)

    Smith, Jonathan Z.; Pearson, Thomas; Gallagher, Eugene V.; Jensen, Tim; Fujiwara, Satoko

    2014-01-01

    This interview was recorded in November 2012 in Jonathan Z. Smith's Hyde Park graystone. Professor Smith offers insights into how he thinks about his classroom teaching and his students' learning through descriptions of various assignments and classroom activities he has developed over more than forty years of teaching. The discussion…

  11. Theoretical models for supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Woosley, S.E.; Weaver, T.A.

    1981-09-21

    The results of recent numerical simulations of supernova explosions are presented and a variety of topics discussed. Particular emphasis is given to (i) the nucleosynthesis expected from intermediate mass (10sub solar less than or equal to M less than or equal to 100 Msub solar) Type II supernovae and detonating white dwarf models for Type I supernovae, (ii) a realistic estimate of the ..gamma..-line fluxes expected from this nucleosynthesis, (iii) the continued evolution, in one and two dimensions, of intermediate mass stars wherein iron core collapse does not lead to a strong, mass-ejecting shock wave, and (iv) the evolution and explosion of vary massive stars (M greater than or equal to 100 Msub solar of both Population I and III. In one dimension, nuclear burning following a failed core bounce does not appear likely to lead to a supernova explosion although, in two dimensions, a combination of rotation and nuclear burning may do so. Near solar proportions of elements from neon to calcium and very brilliant optical displays may be created by hypernovae, the explosions of stars in the mass range 100 M/sub solar/ to 300 M/sub solar/. Above approx. 300 M/sub solar/ a black hole is created by stellar collapse following carbon ignition. Still more massive stars may be copious producers of /sup 4/He and /sup 14/N prior to their collapse on the pair instability.

  12. Supernova 2013by

    DEFF Research Database (Denmark)

    Valenti, S.; Sand, D.; Stritzinger, M.

    2015-01-01

    We present multiband ultraviolet and optical light curves, as well as visual-wavelength and near-infrared spectroscopy of the Type II linear (IIL) supernova (SN) 2013by. We show that SN 2013by and other SNe IIL in the literature, after their linear decline phase that start after maximum, have...

  13. QCD and Supernovas

    Science.gov (United States)

    Barnes, T.

    2005-12-01

    In this contribution we briefly summarize aspects of the physics of QCD which are relevant to the supernova problem. The topic of greatest importance is the equation of state (EOS) of nuclear and strongly-interacting matter, which is required to describe the physics of the proto-neutron star (PNS) and the neutron star remnant (NSR) formed during a supernova event. Evaluation of the EOS in the regime of relevance for these systems, especially the NSR, requires detailed knowledge of the spectrum and strong interactions of hadrons of the accessible hadronic species, as well as other possible phases of strongly interacting matter, such as the quark-gluon plasma (QGP). The forces between pairs of baryons (both nonstrange and strange) are especially important in determining the EOS at NSR densities. Predictions for these forces are unfortunately rather model dependent where not constrained by data, and there are several suggestions for the QCD mechanism underlying these short-range hadronic interactions. The models most often employed for determining these strong interactions are broadly of two types, 1) meson exchange models (usually assumed in the existing neutron star and supernova literature), and 2) quark-gluon models (mainly encountered in the hadron, nuclear and heavy-ion literature). Here we will discuss the assumptions made in these models, and discuss how they are applied to the determination of hadronic forces that are relevant to the supernova problem.

  14. The Most Luminous Supernovae

    CERN Document Server

    Sukhbold, Tuguldur

    2016-01-01

    Recent observations have revealed an amazing diversity of extremely luminous supernovae, seemingly increasing in radiant energy without bound. We consider here the physical limits of what existing models can provide for the peak luminosity and total radiated energy for non-relativistic, isotropic stellar explosions. The brightest possible supernova is a Type I explosion powered by a sub-millisecond magnetar. Such models can reach a peak luminosity of $\\rm 2\\times10^{46}\\ erg\\ s^{-1}$ and radiate a total energy of $\\rm 4 \\times10^{52}\\ erg$. Other less luminous models are also explored, including prompt hyper-energetic explosions in red supergiants, pulsational-pair instability supernovae, and pair-instability supernovae. Approximate analytic expressions and limits are given for each case. Excluding magnetars, the peak luminosity is near $\\rm 1\\times10^{44}\\ erg\\ s^{-1}$ for the brightest models. The corresponding limits on total radiated power are $\\rm3 \\times 10^{51}\\ erg$ (Type I) and $\\rm1 \\times 10^{51}\\ ...

  15. Supernovae and Dark Energy

    Science.gov (United States)

    Domínguez, I.; Bravo, E.; Piersanti, L.; Straniero, O.; Tornambé, A.

    2009-08-01

    A decade ago the observations of thermonuclear supernovae at high-redhifts showed that the expansion rate of the Universe is accelerating and since then, the evidence for cosmic acceleration has gotten stronger. This acceleration requires that the Universe is dominated by dark energy, an exotic component characterized by its negative pressure. Nowadays all the available astronomical data (i.e. thermonuclear supernovae, cosmic microwave background, barionic acoustic oscillations, large scale structure, etc.) agree that our Universe is made of about 70% of dark energy, 25% of cold dark matter and only 5% of known, familiar matter. This Universe is geometrically flat, older than previously thought, its destiny is no longer linked to its geometry but to dark energy, and we ignore about 95% of its components. To understand the nature of dark energy is probably the most fundamental problem in physics today. Current astronomical observations are compatible with dark energy being the vacuum energy. Supernovae have played a fundamental role in modern Cosmology and it is expected that they will contribute to unveil the dark energy. In order to do that it is mandatory to understand the limits of supernovae as cosmological distance indicators, improving their precision by a factor 10.

  16. STS-110 Crew Interviews: Steve Smith

    Science.gov (United States)

    2002-01-01

    STS-110 Mission Specialist Steve Smith is seen during this preflight interview, where he gives a quick overview of the mission before answering questions about his inspiration to become an astronaut and his career path. Smith outlines his role in the mission in general, and specifically during the docking and extravehicular activities (EVAs). He describes the payload (S0 Truss and Mobile Transporter) and the dry run installation of the S0 truss that will take place the day before the EVA for the actual installation. Smith discusses the planned EVAs in detail and outlines what supplies will be left for the resident crew of the International Space Station (ISS). He ends with his thoughts on the most valuable aspect of the ISS.

  17. Infrared Light Curves of Type Ia Supernovae

    Science.gov (United States)

    Friedman, Andrew Samuel

    2012-05-01

    This thesis presents the CfAIR2 data set, which includes over 4000 near-Infrared (NIR) JHK8-band measurements of 104 Type Ia Supernovae (SN Ia) observed from 2005-2011 using PAIRITEL, the 1.3-m Peters Automated InfraRed Imaging TELescope at the Fred Lawrence Whipple Observatory (FLWO) on Mount Hopkins, Arizona. While the discovery of dark energy and most subsequent supernova cosmology has been performed using optical and Ultraviolet wavelength observations of SN Ia, a growing body of evidence suggests that NIR SN Ia observations will be crucial for future cosmological studies. Whereas SN Ia observed at optical wavelengths have been shown to be excellent standardizeable candles, using empirical correlations between luminosity, light curve shape, and color, the CfAIR2 data set strengthens the evidence that SN Ia at NIR wavelengths are essentially standard candles, even without correction for light-curve shape or for reddening. CfAIR2 was obtained as part of the CfA Supernova Program, an ongoing multi-wavelength follow-up effort at FLWO designed to observe high-quality, densely sampled light curves and spectra of hundreds of low-redshift SN Ia. CfAIR2 is the largest homogeneously observed and processed NIR data set of its kind to date, nearly tripling the number of individual JHK8-band observations and nearly doubling the set of SN Ia with published NIR light curves in the literature. Matched only by the recently published Carnegie Supernova Project sample, CfAIR2 complements the large and growing set of low-redshift optical and NIR SN Ia observations obtained by the CfA and other programs, making this data set a unique and particularly valuable local universe anchor for future supernova cosmology.

  18. Seidel-Smith cohomology for tangles

    DEFF Research Database (Denmark)

    Rezazadegan, Reza

    2009-01-01

    We generalize the “symplectic Khovanov cohomology” of Seidel and Smith (Duke Math J 134(3):453–514, 2006) to tangles using the notion of symplectic valued topological field theory introduced by Wehrheim and Woodward (arXiv:0905.1368).......We generalize the “symplectic Khovanov cohomology” of Seidel and Smith (Duke Math J 134(3):453–514, 2006) to tangles using the notion of symplectic valued topological field theory introduced by Wehrheim and Woodward (arXiv:0905.1368)....

  19. Smith-Magenis Syndrome: Face Speaks.

    Science.gov (United States)

    Gupta, Rekha; Gupta, Neerja; Nampoothiri, Sheela; Mandal, Kausik; Kishore, Yougal; Sharma, Pankaj; Kabra, Madhulika; Phadke, Shubha R

    2016-06-01

    Smith-Magenis syndrome is a well delineated microdeletion syndrome with characteristic facial and behavioral phenotype. With the availability of the multi-targeted molecular cytogenetic techniques like Multiplex Ligation Probe Amplification and cytogenetic microarray, the cases are diagnosed even without clinical suspicion. Here, the authors present clinical features of nine Indian cases of Smith-Magenis syndrome. Characteristic facial phenotype including tented upper lip, broad forehead, midface hypoplasia, short philtrum and upslant of palpebral fissure is obvious in the photographs. The behavioral variations were seen in some of the cases but were not the presenting features. The characteristic facial phenotype can be an important clinical guide to the diagnosis.

  20. Smith Predictor Based Robust Rapid Tracking Controller

    Institute of Scientific and Technical Information of China (English)

    LIU Hongbin; HU Dejin

    2006-01-01

    Precise model is hard to get in real application, a Smith predictor based robust rapid tracking controller for inaccurate model is proposed. Zero phase error feedforward controller which increases system closed-loop dynamics and disturbance observer based Smith feedback control which diminishes model hysteresis and improves stability are integrated. This method is applied in the noncircular machining with piezoelectric ceramic driver. The simulation and experiment show that the performance robustness and stability are well balanced in bandwidth about 200 Hz. The controller can decrease system hysteresis and get good tracking performance for predefined square-wave input signal.

  1. Illustrated & Dissected: Professor Richard Sawdon Smith.

    Science.gov (United States)

    2015-06-01

    This Alternative Gallery feature introduces the photographic artist Professor Richard Sawdon Smith. Professor Sawdon Smith's work stems around a fascination with representations of anatomy that have been fuelled by his experience as a hospital patient. The work has allowed him to explore ideas through the use of medical illustrations which include early anatomical drawings, personal medical photography and facial modelling. The work highlights how such imagery can be used in the context of a patient seeking understanding and acceptance of ill health and disease using the body as a canvas on which to translate the experience.

  2. Analysis of the Modified Smith Predictor

    Directory of Open Access Journals (Sweden)

    Jorge A. Herrera-Cuartas

    2013-11-01

    Full Text Available In this paper an analysis about the modified Smith predictor, is presented. The modified Smith predictor is a scheme used to control stable, unstable and integrative systems. The closed loop equation is developed and analyzed. Additionally, various test are made to verify the behavior of the control scheme. Specify, three test are made. First, it is verify the behavior of the scheme to deal with an uncertainty in the delay model. Second, it is verify the behavior in the face of uncertainties in the parameter of the rational model. 

  3. Adam Smith on public expenditure and taxation

    Directory of Open Access Journals (Sweden)

    Maurício C. Coutinho

    2001-01-01

    Full Text Available This paper presents Adam Smith’s view on taxation and public expenditure, by means of an almost literal reading of the Wealth of Nations famous passages on the "duties of the sovereign" and on the "maxims of taxation". Contrarily to the commonest usage of these passages, we will show that their core is the preoccupation with the public expenditure soaring and the defence of decentralisation. Furthermore and also contrarily to the existing interpretations we defend the non-existence of any contradiction between Smith’s income and price theory (and the incidence hypothesis, provided due attention is paid to the guiding role of the "maxims".

  4. "Type Ia Supernovae: Tools for Studying Dark Energy" Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Woosley, Stan [Lick Observatory, San Jose, CA (United States); Kasen, Dan [Univ. of California, Berkeley, CA (United States)

    2017-05-10

    Final technical report for project "Type Ia Supernovae: Tools for the Study of Dark Energy" awarded jointly to scientists at the University of California, Santa Cruz and Berkeley, for computer modeling, theory and data analysis relevant to the use of Type Ia supernovae as standard candles for cosmology.

  5. Field guide to research at Neal Smith National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document contains a summary of research conducted at Neal Smith National Wildlife Refuge. Research at Neal Smith has resulted in the publication of over 60...

  6. Dialogues with Marilyn Cochran-Smith

    Science.gov (United States)

    Fiorentini, Dario; Crecci, Vanessa Moreira

    2015-01-01

    For more than 30 years, Dr. Marilyn Cochran-Smith has developed and directed research and contributed to publications about education and "practitioner research," especially about teachers' research and learning in inquiry communities. Her primary topics are inquiry communities, teacher research, teacher education for social…

  7. John Smith - eesti kunstnik / Ants Juske

    Index Scriptorium Estoniae

    Juske, Ants, 1956-

    2006-01-01

    Marko Mäetamme ja Kaido Ole kollektiivsest loomingust, mida esitatakse John Smithi autorinime all, mõnda ka salapärase J. Smithi nn. biograafiast. Illustratsiooniks J. Smith'i "Jumalate maailm I (fragment). Õli, lõuend, 2002. Erakogu

  8. Adam Smith, Market and Social Change

    DEFF Research Database (Denmark)

    Bouchet, Dominique

    2017-01-01

    Adam Smith (1723-1790) provided us with a remarkable synthesis of the economic and political ideas of his time and developed a conceptual system to analyse social interactions that mattered for the wealth of nations. He proposed a radically different roadmap for the future development of the soci......Adam Smith (1723-1790) provided us with a remarkable synthesis of the economic and political ideas of his time and developed a conceptual system to analyse social interactions that mattered for the wealth of nations. He proposed a radically different roadmap for the future development...... of the society he lived in. The fact that his original analyses were rooted in a given historical context and were founded on a well thought-through conceptual system should not be ignored. The galvanising effect of the dribs and drabs of Adam Smith ideas that have been bandied about are a long way from...... the powerful insights imbued in the original ideas. Putting those back into context, looking into how Smith proceeded then, trying to update his observations, might help us to be more attentive to the market changes and social challenges of our times....

  9. Adam Smith, Religion, and Tuition Tax Credits.

    Science.gov (United States)

    Alexander, Kern

    1983-01-01

    Examines tuition tax credit programs in framework of Adam Smith's ideas on the economic impact of established churches. Finds that tuition tax credits would amount to state expenditures to relieve the financial burden of parochial school parents and would allow churches to invest commercially to maintain their charitable functions. (JW)

  10. John Smith - eesti kunstnik / Ants Juske

    Index Scriptorium Estoniae

    Juske, Ants, 1956-2016

    2006-01-01

    Marko Mäetamme ja Kaido Ole kollektiivsest loomingust, mida esitatakse John Smithi autorinime all, mõnda ka salapärase J. Smithi nn. biograafiast. Illustratsiooniks J. Smith'i "Jumalate maailm I (fragment). Õli, lõuend, 2002. Erakogu

  11. Adam Smith, Religion, and Tuition Tax Credits.

    Science.gov (United States)

    Alexander, Kern

    1983-01-01

    Examines tuition tax credit programs in framework of Adam Smith's ideas on the economic impact of established churches. Finds that tuition tax credits would amount to state expenditures to relieve the financial burden of parochial school parents and would allow churches to invest commercially to maintain their charitable functions. (JW)

  12. Patti Smith: Aging, fandom, and libido

    Directory of Open Access Journals (Sweden)

    Maud Lavin

    2015-09-01

    Full Text Available This essay traces a lifelong fandom of Patti Smith in light of issues of aging, femininity, and libido. It also considers the paucity of transformative images in Western mass culture and its fandoms of aging women. Personal narrative is brought into play, fans' experiences throughout the life cycle are referenced, and gender issues are emphasized.

  13. Collective supernova neutrino oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Mirizzi, Alessandro [Max Planck Institute for Physics, Munich (Germany)

    2009-07-01

    Neutrinos emitted by core-collapse supernovae (SNe) represent an important laboratory for both particle physics and astrophysics. While propagating in the dense SN environment, they can feel not only the presence of background matter (via ordinary Mikheev-Smirnov-Wolfenstein effects) but also of the gas of neutrinos and antineutrinos (via neutrino-neutrino interaction effects). The neutrino-neutrino interactions appear to modify the flavor evolution of SN neutrinos in a collective way, completely different from the ordinary matter effects. In these conditions, the flavor evolution equations become highly nonlinear, sometimes resulting in surprising phenomena when the entire neutrino system oscillates coherently as a single collective mode. In this talk, I present the recent results on collective supernova neutrino flavor conversions and I discuss about the sensitivity of these effects to the ordering of the neutrino mass spectrum.

  14. ADIDAS SUPERNOVA CTR10

    Institute of Scientific and Technical Information of China (English)

    刘楠

    2008-01-01

    ADIDAS SUPERNOVA CTR10作为ADIDAS控制型跑鞋中的佼佼者,鞋款结合了如立体FORMOTION,大面积的PRO-MODERATOR特殊材质,以及强化型的07款鞋模(EL-07),前脚掌大块ADIPRENE+等诸多ADIDAS的当家技术,但在实际的跑步过程中,这些技术点能否真正为跑步者带来明显的感受?请随我们进入到ADIDAS SUPERNOVA CONTROL10评测环节。

  15. Galaxy Outflows Without Supernovae

    CERN Document Server

    Sur, Sharanya; Ostriker, Eve C

    2016-01-01

    High surface density, rapidly star-forming galaxies are observed to have $\\approx 50-100\\,{\\rm km\\,s^{-1}}$ line-of-sight velocity dispersions, which are much higher than expected from supernova driving alone, but may arise from large-scale gravitational instabilities. Using three-dimensional simulations of local regions of the interstellar medium, we explore the impact of high velocity dispersions that arise from these disk instabilities. Parametrizing disks by their surface densities and epicyclic frequencies, we conduct a series of simulations that probe a broad range of conditions. Turbulence is driven purely horizontally and on large scales, neglecting any energy input from supernovae. We find that such motions lead to strong global outflows in the highly-compact disks that were common at high redshifts, but weak or negligible mass loss in the more diffuse disks that are prevalent today. Substantial outflows are generated if the one-dimensional horizontal velocity dispersion exceeds $\\approx 35\\,{\\rm km\\...

  16. Supernova Science Center

    Energy Technology Data Exchange (ETDEWEB)

    S. E. Woosley

    2008-05-05

    The Supernova Science Center (SNSC) was founded in 2001 to carry out theoretical and computational research leading to a better understanding of supernovae and related transients. The SNSC, a four-institutional collaboration, included scientists from LANL, LLNL, the University of Arizona (UA), and the University of California at Santa Cruz (UCSC). Intitially, the SNSC was funded for three years of operation, but in 2004 an opportunity was provided to submit a renewal proposal for two years. That proposal was funded and subsequently, at UCSC, a one year no-cost extension was granted. The total operational time of the SNSC was thus July 15, 2001 - July 15, 2007. This document summarizes the research and findings of the SNSC and provides a cummulative publication list.

  17. Nurseries of Supernovae

    DEFF Research Database (Denmark)

    Frederiksen, Teddy

    Type Ia supernovae (SNe) have long been the gold standard for precision cosmology and after several decades of intense research the supernova (SN) community was in 2011 honored by giving the Nobel Prize in physics for the discovery of Dark Energy to the leaders of the two big SN collaborations...... the gasphase metallicity, stellar mass and stellar age for this z = 1.55 host galaxy. I am also able to rule out the presence of any AGN though emission-line ratios. The host is classified as a highly star forming, low mass, low metallicity galaxy. It is a clear outlier in star formation and stellar mass...... compared to most low redshift (z 1) redshift SNe. This is mainly due to the change in specific star-formation rate as a function of redshift. This can potentially impact the use of high redshift SN Ia as standard candels...

  18. SALT Spectroscopy of ASASSN-15lh: The Most Luminous Supernova?

    Science.gov (United States)

    Court, Travis; Camacho, Yssavo; Dettman, Kyle; Jha, Saurabh W.

    2017-01-01

    In August 2015, ASASSN-15lh was discovered as the most luminous supernova (SN) ever found (Dong et al. 2016), more than twice as bright as other so-called super-luminous supernovae (SLSN). However, the spectral evolution of the transient is unlike any known supernova. To better understand this object, we have observed ASASSN-15lh with the Southern African Large Telescope (SALT). We obtained spectroscopic data in July 2016 and reduced and calibrated the spectrum for comparison with other supernovae. The new pectrum did not show strong supernova features and was dominated by light from the host galaxy. We used this late spectrum as a galaxy template, subtracting it from earlier data. However, we still find that ASASSN-15lh does not clearly resemble any known supernova. Either it is unique, or perhaps an alternate explanation is needed (e.g., a tidal disruption event; Leloudas et al. 2016). This Research Experience for Undergraduates project in the Department of Physics and Astronomy at Rutgers University has been supported by funding from National Science Foundation grants PHY-1263280 and PHY-1560077.

  19. SR-71 Pilot Rogers E. Smith

    Science.gov (United States)

    1992-01-01

    Research pilot Rogers E. Smith is shown here in front of the SR-71 Blackbird he flew for NASA. Rogers was one of the two original NASA research pilots assigned to the SR-71 high speed research program at NASA's Ames-Dryden Flight Research Facility (later, Dryden Flight Research Center, Edwards, California. Smith has been a NASA research pilot at Dryden since 1982. Data from the SR-71 program will be used to aid designers of future supersonic aircraft and propulsion systems. The SR-71 is capable of flying more than 2200 mph (Mach 3+) and at altitudes of over 80,000 feet. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data

  20. Results from the Supernova Photometric Classification Challenge

    CERN Document Server

    Kessler, Richard; Belov, Pavel; Bhatnagar, Vasudha; Campbell, Heather; Conley, Alex; Frieman, Joshua A; Glazov, Alexandre; Hlozek, Santiago Gonzalez-Gaitan Renee; Jha, Saurabh; Kuhlmann, Stephen; Kunz, Martin; Lampeitl, Hubert; Mahabal, Ashish; Newling, James; Nichol, Robert C; Parkinson, David; Philip, Ninan Sajeeth; Poznanski, Dovi; Richards, Joseph W; Rodney, Steven A; Sako, Masao; Schneider, Donald P; Smith, Mathew; Stritzinger, Maximilian; Varughese, Melvin

    2010-01-01

    We report results from the Supernova Photometric Classification Challenge (SNPCC), a publicly released mix of simulated SNe, with types (Ia, Ibc, II) selected in proportion to their expected rate. The simulation was realized in the griz filters of the Dark Energy Survey (DES) with realistic observing conditions (sky noise, point spread function and atmospheric transparency) based on years of recorded conditions at the DES site. Simulations of non-Ia type SNe are based on spectroscopically confirmed light curves that include unpublished non-Ia samples donated from the Carnegie Supernova Project (CSP), the Supernova Legacy Survey (SNLS), and the Sloan Digital Sky Survey-II (SDSS-II). A spectroscopically confirmed subset was provided for training. We challenged scientists to run their classification algorithms and report a type and photo-z for each SN. Participants from 10 groups contributed 13 entries for the sample that included a host galaxy photo-z for each SN, and 9 entries for the sample that had no redshi...

  1. Observations and Theory of Supernovae

    CERN Document Server

    Wheeler, J C

    2003-01-01

    This Resource Letter provides a guide to the literature on the observations of supernovae and the theory of their explosion mechanisms. Journal articles and books are cited for the following topics: observations of the spectra, spectropolarimetry, and light curves of supernovae of various types, theory of thermonuclear explosions, core collapse, and radioactive decay, applications to cosmology, and possible connections to gamma-ray bursts.

  2. Collective neutrino oscillations in supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Huaiyu [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States)

    2014-06-24

    In a dense neutrino medium neutrinos can experience collective flavor transformation through the neutrino-neutrino forward scattering. In this talk we present some basic features of collective neutrino flavor transformation in the context in core-collapse supernovae. We also give some qualitative arguments for why and when this interesting phenomenon may occur and how it may affect supernova nucleosynthesis.

  3. Mass Varying Neutrinos in Supernovae

    CERN Document Server

    Rossi-Torres, F; de Holanda, P C; Peres, O L G

    2010-01-01

    We study limits for the mass varying neutrino model, using constrains from supernova neutrinos placed by the r-process condition, $Y_e<0.5$. Also, we use this model in a supernova environment to study the regions of survival probability in the oscillation space parameter ($\\tan^2\\theta$ and $\\Delta m^2_0$), considering the channel $\

  4. Stable LPV realisation of the Smith predictor

    Science.gov (United States)

    Blanchini, Franco; Casagrande, Daniele; Miani, Stefano; Viaro, Umberto

    2016-07-01

    The paper is concerned with the control of a linear plant with an output delay. As is known, when the plant parameters do not vary in time, the transfer function approach can be used to find a high-performing controller with the Smith-predictor structure. Such an approach in the domain of the Laplace transform is not directly applicable in the time-variant case. Nevertheless, it is shown that the transfer function of the Smith controller valid for constant values of the parameters can be realised in such a way that closed-loop stability, as well as point-wise optimal performance, is ensured also when the parameters vary with time. The suggested technique is applied to the control of a heat exchanger whose varying parameters include a measurement delay.

  5. Adam Smith et les passions musicales

    Directory of Open Access Journals (Sweden)

    Marc Parmentier

    2012-02-01

    Full Text Available Dans sa Théorie des sentiments moraux (1759, Adam Smith classe les passions en trois catégories : passions sociales, asociales, égoïstes. Cette classification résulte directement de leur capacité à susciter ou non la sympathie. Les passions sociales apparaissent ainsi comme les plus propres à susciter un écho sympathique. La question à laquelle tente de répondre l'article est de savoir pourquoi ces mêmes passions sociales sont qualifiées par A. Smith de « naturellement musicales ». L'utilisation du concept de sympathie dans le domaine musical est fréquente aux XVIIème et XVIIIème siècles, mais l'hypothèse avancée ici est que le lien est plus profond chez A. Smith. La sympathie met en effet en évidence une qualité d'ordre à la fois esthétique et morale inhérente à certaines passions, leur « convenance » (propriety par opposition aux passions « discordantes ». Ces passions, produisant une superposition d'échos sympathiques comparables aux harmoniques d'un ton fondamental, sont les plus susceptibles d'être imitées par la musique, si l'on tient compte de la théorie esthétique originale formulée par A. Smith, pour qui la beauté des arts imitatifs ne tient pas à l'illusion mais au contraire à l'écart entre l'imitation et son objet.In his Theory of Moral Sentiments, Adam Smith distinguishes three types of passions: social passions, unsocial passions and selfish passions. This classification relies on their capacity to evoke sympathy. Social passions are the most apt to arouse a sympathetic echo in their observers. This article tries to answer the question why A. Smith describes social passions as « naturally musical ». In 17th and 18th centuries sympathy is often mentioned in connection with musical topics, but the link established by A. Smith is more profound. In fact, sympathy reveals an esthetic and moral quality of « convenient », vs « discordant », passions. These passions, that produce

  6. La pobreza en Smith y Ricardo

    Directory of Open Access Journals (Sweden)

    Pardo Beltrán, Edgar

    2000-06-01

    Full Text Available Este artículo compara los enfoques de Adam Smith y David Ricardo sobre la pobreza en una sociedad capitalista. La comparación se centra alrededor de los diferentes argumentos que ellos utilizan para relacionar la pobreza con la inequidad y las realidades institucionales. La discusión se contextualiza en las experiencias vividas de cada autor, así como en los intereses intelectuales de cada uno; teniendo en cuenta que la pobreza fue uno de los principales problemas que enfrentó Inglaterra entre el siglo XVIII y XIX. La postura de Smith establece una relación entre la pobreza y la estabilidad del orden social; mientras que la perspectiva de Ricardo postula la pobreza como función de los conflictos distributivos y las fuerzas del crecimiento de la población.

  7. Computational Astrophysics Consortium 3 - Supernovae, Gamma-Ray Bursts and Nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Woosley, Stan [Univ. of California, Santa Cruz, CA (United States)

    2014-08-29

    Final project report for UCSC's participation in the Computational Astrophysics Consortium - Supernovae, Gamma-Ray Bursts and Nucleosynthesis. As an appendix, the report of the entire Consortium is also appended.

  8. Cosmological and supernova neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Kajino, T. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan Department of Astronomy, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); Aoki, W. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Balantekin, A. B. [Department of Physics, University of Wisconsin - Madison, Wisconsin 53706 (United States); Cheoun, M.-K. [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Hayakawa, T. [Japan Atomic Energy Agency, Shirakara-Shirane 2-4, Tokai-mura, Ibaraki 319-1195 (Japan); Hidaka, J. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Hirai, Y.; Shibagaki, S. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan and Department of Astronomy, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); Kusakabe, M. [School of Liberal Arts and Science, Korea Aerospace University, Goyang 412-791 (Korea, Republic of); Mathews, G. J. [Department of Physics, University of Notre Dame, IN 46556 (United States); Nakamura, K. [Waseda University, Ohkubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Pehlivan, Y. [Mimar Sinan GSÜ, Department of Physics, Şişli, İstanbul 34380 (Turkey); Suzuki, T. [Nihon University, Sakurajosui 3-25-40, Setagaya-ku, Tokyo 156-8550 (Japan)

    2014-06-24

    The Big Bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) anisotropies are the pillars of modern cosmology. It has recently been suggested that axion which is a dark matter candidate in the framework of the standard model could condensate in the early universe and induce photon cooling before the epoch of the photon last scattering. Although this may render a solution to the overproduction problem of primordial {sup 7}Li abundance, there arises another serious difficulty of overproducing D abundance. We propose a hybrid dark matter model with both axions and relic supersymmetric (SUSY) particles to solve both overproduction problems of the primordial D and {sup 7}Li abundances simultaneously. The BBN also serves to constrain the nature of neutrinos. Considering non-thermal photons produced in the decay of the heavy sterile neutrinos due to the magnetic moment, we explore the cosmological constraint on the strength of neutrino magnetic moment consistent with the observed light element abundances. Core-collapse supernovae eject huge flux of energetic neutrinos which affect explosive nucleosynthesis of rare isotopes like {sup 7}Li, {sup 11}B, {sup 92}Nb, {sup 138}La and {sup 180}Ta and r-process elements. Several isotopes depend strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. Combining the recent experimental constraints on θ{sub 13} with predicted and observed supernova-produced abundance ratio {sup 11}B/{sup 7}Li encapsulated in the presolar grains from the Murchison meteorite, we show a marginal preference for an inverted neutrino mass hierarchy. We also discuss supernova relic neutrinos (SRN) that may indicate the softness of the equation of state (EoS) of nuclear matter and adiabatic conditions of the neutrino oscillation.

  9. Cosmology with superluminous supernovae

    Science.gov (United States)

    Scovacricchi, D.; Nichol, R. C.; Bacon, D.; Sullivan, M.; Prajs, S.

    2016-02-01

    We predict cosmological constraints for forthcoming surveys using superluminous supernovae (SLSNe) as standardizable candles. Due to their high peak luminosity, these events can be observed to high redshift (z ˜ 3), opening up new possibilities to probe the Universe in the deceleration epoch. We describe our methodology for creating mock Hubble diagrams for the Dark Energy Survey (DES), the `Search Using DECam for Superluminous Supernovae' (SUDSS) and a sample of SLSNe possible from the Large Synoptic Survey Telescope (LSST), exploring a range of standardization values for SLSNe. We include uncertainties due to gravitational lensing and marginalize over possible uncertainties in the magnitude scale of the observations (e.g. uncertain absolute peak magnitude, calibration errors). We find that the addition of only ≃100 SLSNe from SUDSS to 3800 Type Ia Supernovae (SNe Ia) from DES can improve the constraints on w and Ωm by at least 20 per cent (assuming a flat wCDM universe). Moreover, the combination of DES SNe Ia and 10 000 LSST-like SLSNe can measure Ωm and w to 2 and 4 per cent, respectively. The real power of SLSNe becomes evident when we consider possible temporal variations in w(a), giving possible uncertainties of only 2, 5 and 14 per cent on Ωm, w0 and wa, respectively, from the combination of DES SNe Ia, LSST-like SLSNe and Planck. These errors are competitive with predicted Euclid constraints, indicating a future role for SLSNe for probing the high-redshift Universe.

  10. GALAXY OUTFLOWS WITHOUT SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Sur, Sharanya [Indian Institute of Astrophysics, 2nd Block, Koramangala, Bangalore 560034 (India); Scannapieco, Evan [School of Earth and Space Exploration, Arizona State University, P.O. Box 876004, Tempe-85287 (United States); Ostriker, Eve C., E-mail: sharanya.sur@iiap.res.in, E-mail: sharanya.sur@asu.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2016-02-10

    High surface density, rapidly star-forming galaxies are observed to have ≈50–100 km s{sup −1} line of sight velocity dispersions, which are much higher than expected from supernova driving alone, but may arise from large-scale gravitational instabilities. Using three-dimensional simulations of local regions of the interstellar medium, we explore the impact of high velocity dispersions that arise from these disk instabilities. Parametrizing disks by their surface densities and epicyclic frequencies, we conduct a series of simulations that probe a broad range of conditions. Turbulence is driven purely horizontally and on large scales, neglecting any energy input from supernovae. We find that such motions lead to strong global outflows in the highly compact disks that were common at high redshifts, but weak or negligible mass loss in the more diffuse disks that are prevalent today. Substantial outflows are generated if the one-dimensional horizontal velocity dispersion exceeds ≈35 km s{sup −1}, as occurs in the dense disks that have star-formation rate (SFR) densities above ≈0.1 M{sub ⊙} yr{sup −1} kpc{sup −2}. These outflows are triggered by a thermal runaway, arising from the inefficient cooling of hot material coupled with successive heating from turbulent driving. Thus, even in the absence of stellar feedback, a critical value of the SFR density for outflow generation can arise due to a turbulent heating instability. This suggests that in strongly self-gravitating disks, outflows may be enhanced by, but need not caused by, energy input from supernovae.

  11. Supernovae anisotropy power spectrum

    CERN Document Server

    Ghodsi, Hoda; Habibi, Farhang

    2016-01-01

    We contribute another anisotropy study to this field of research using Supernovae Type Ia (SNe Ia). In this work, we utilise the power spectrum calculation method and apply it to both the current SNe Ia data and simulation. Our simulations are constructed with the characteristics of the upcoming survey of the Large Synoptic Survey Telescope (LSST), which shall bring us the largest SNe Ia collection to date. We make predictions for the amplitude of a possible dipole anisotropy or anisotropy in higher multipole moments that would be detectable by the LSST.

  12. X-Ray Supernovae

    CERN Document Server

    Immler, S; Immler, Stefan; Lewin, Walter H.G.

    2002-01-01

    We present a review of X-ray observations of supernovae (SNe). By observing the (~0.1--100 keV) X-ray emission from young SNe, physical key parameters such as the circumstellar matter (CSM) density, mass-loss rate of the progenitor and temperature of the outgoing and reverse shock can be derived as a function of time. Despite intensive search over the last ~25 years, only 15 SNe have been detected in X-rays. We review the individual X-ray observations of these SNe and discuss their implications as to our understanding of the physical processes giving rise to the X-ray emission.

  13. Automated Supernova Discovery (Abstract)

    Science.gov (United States)

    Post, R. S.

    2015-12-01

    (Abstract only) We are developing a system of robotic telescopes for automatic recognition of Supernovas as well as other transient events in collaboration with the Puckett Supernova Search Team. At the SAS2014 meeting, the discovery program, SNARE, was first described. Since then, it has been continuously improved to handle searches under a wide variety of atmospheric conditions. Currently, two telescopes are used to build a reference library while searching for PSN with a partial library. Since data is taken every night without clouds, we must deal with varying atmospheric and high background illumination from the moon. Software is configured to identify a PSN, reshoot for verification with options to change the run plan to acquire photometric or spectrographic data. The telescopes are 24-inch CDK24, with Alta U230 cameras, one in CA and one in NM. Images and run plans are sent between sites so the CA telescope can search while photometry is done in NM. Our goal is to find bright PSNs with magnitude 17.5 or less which is the limit of our planned spectroscopy. We present results from our first automated PSN discoveries and plans for PSN data acquisition.

  14. Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study

    CERN Document Server

    Garavini, G; Nobili, S; Aldering, G; Amanullah, R; Antilogus, P; Astier, Pierre; Blanc, G; Bronder, J; Burns, M S; Conley, A; Deustua, S E; Doi, M; Fabbro, S; Fadeev, V; Gibbons, R; Goldhaber, G; Goobar, A; Groom, D E; Hook, I; Howell, D A; Kashikawa, N; Kim, A G; Kowalski, M; Kuznetsova, N; Lee, B C; Lidman, C; Méndez, J; Morokuma, T; Motohara, K; Nugent, P; Pain, R; Perlmutter, S; Quimby, R; Raux, J; Regnault, N; Ruiz-Lapuente, P; Sainton, G; Schahmaneche, K; Smith, E; Spadafora, A L; Stanishev, V; Thomas, R C; Walton, N A; Wang, L; Wood-Vasey, W M; Project, N Y T S C

    2007-01-01

    We develop a method to measure the strength of the absorption features in Type Ia supernova (SN Ia) spectra and use it to make a quantitative comparison between the spectra of Type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 < z < 0.912) SNe Ia observed by the Supernova Cosmology Project . Through measurements of the strengths of these features and of the blueshift of the absorption minimum in Ca II H&K, we show that the spectra of the high-redshift SNe Ia are quantitatively similar to spectra of nearby SNe Ia (z < 0.15). One supernova in our high redshift sample, SN 2002fd at z=0.279, is found to have spectral characteristics that are associated with peculiar SN 1991T/SN 1999aa-like supernovae.

  15. The Acceleration of the Universe in the Light of Supernovae: The Key Role of CTIO

    Science.gov (United States)

    Hamuy, M.; Suntzeff, N. B.

    2015-05-01

    The discovery of acceleration and dark energy arguably constitutes the most revolutionary discovery in astrophysics in recent years. The Cerro Tololo Inter-American Observatory (CTIO) played a key role in this amazing discovery through three systematic surveys organized by staff astronomers: the “Tololo Supernova Program“ (1986-2000), the Calán/Tololo Project (1989-1993), and the “High-Z Supernova Search Team” (1994-1998). CTIO's state of the art instruments also were fundamental in the independent discovery of acceleration by the “Supernova Cosmology Project” (1992-1999). Here I summarize the work on supernovae carried out from CTIO that led to the discovery of acceleration and dark energy and provide a brief historical summary on the use of Type Ia supernovae in cosmology in order to provide context for the CTIO contribution.

  16. Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Supernova Cosmology Project; Nugent, Peter E; Garavini, G.; Folatelli, G.; Nobili, S.; Aldering, G.; Amanullah, R.; Antilogus, P.; Astier, P.; Blanc, G.; Bronder, J.; Burns, M.S.; Conley, A.; Deustua, S. E.; Doi, M.; Fabbro, S.; Fadeyev, V.; Gibbons, R.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hook, I.; Howell, D. A.; Kashikawa, N.; Kim, A. G.; Kowalski, M.; Kuznetsova, N.; Lee, B. C.; Lidman, C.; Mendez, J.; Morokuma, T.; Motohara, K.; Nugent, P. E.; Pain, R.; Perlmutter, S.; Quimby, R.; Raux, J.; Regnault, N.; Ruiz-Lapuente, P.; Sainton, G.; Schahmaneche, K.; Smith, E.; Spadafora, A. L.; Stanishev, V.; Thomas, R. C.; Walton, N. A.; Wang, L.; Wood-Vasey, W. M.; Yasuda, N.

    2008-03-24

    We develop a method to measure the strength of the absorption features in type Ia supernova (SN Ia) spectra and use it to make a quantitative comparisons between the spectra of type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 = z = 0.912) SNe Ia observed by the Supernova Cosmology Project. Through measurements of the strengths of these features and of the blueshift of theabsorption minimum in Ca ii H&K, we show that the spectra of the high-redshift SNe Ia are quantitatively similar to spectra of nearby SNe Ia (z< 0.15). One supernova in our high redshift sample, SN 2002fd at z = 0.279, is found to have spectral characteristics that are associated with peculiar SN 1991T/SN 1999aa-like supernovae.

  17. Design, characterization, and sensitivity of the supernova trigger system at Daya Bay

    CERN Document Server

    Wei, Hanyu; Li, Fei; Wang, Zhe; Chen, Shaomin

    2015-01-01

    Providing an early warning of galactic supernova explosions from neutrino signals is important in studying supernova dynamics and neutrino physics. A dedicated supernova trigger system has been designed and installed in the data acquisition system at Daya Bay and integrated into the worldwide Supernova Early Warning System (SNEWS). Daya Bay's unique feature of eight identically-designed detectors deployed in three separate experimental halls makes the trigger system naturally robust against cosmogenic backgrounds, enabling a prompt analysis of online triggers and a tight control of the false-alert rate. The trigger system is estimated to be fully sensitive to 1987A-type supernova bursts throughout most of the Milky Way. The significant gain in sensitivity of the eight-detector configuration over a mass-equivalent single detector is also estimated. The experience of this online trigger system is applicable to future projects with spatially distributed detectors.

  18. The sloan digital sky survey-II supernova survey

    DEFF Research Database (Denmark)

    Frieman, Joshua A.; Bassett, Bruce; Becker, Andrew

    2008-01-01

    The Sloan Digital Sky Survey-II (SDSS-II) has embarked on a multi-year project to identify and measure light curves for intermediate-redshift (0.05 supernovae (SNe Ia) using repeated five-band (ugriz) imaging over an area of 300 sq. deg. The survey region is a stripe 2.5° wide...... centered on the celestial equator in the Southern Galactic Cap that has been imaged numerous times in earlier years, enabling construction of a deep reference image for the discovery of new objects. Supernova imaging observations are being acquired between September 1 and November 30 of 2005-7. During...... the first two seasons, each region was imaged on average every five nights. Spectroscopic follow-up observations to determine supernova type and redshift are carried out on a large number of telescopes. In its first two three-month seasons, the survey has discovered and measured light curves for 327...

  19. The Supernova Type Ia Rate Evolution with SNLS

    CERN Document Server

    Neill, J D; Balam, D; Pritchet, C J; Howell, D A; Perrett, K; Astier, Pierre; Aubourg, E; Basa, S; Carlberg, R G; Conley, A; Fabbro, S; Fouchez, D; Guy, J; Hook, I; Pain, R; Palanque-Delabrouille, Nathalie; Regnault, N; Rich, J; Taillet, R; Aldering, G; Antilogus, P; Arsenijevic, V; Balland, C; Baumont, S; Bronder, J; Ellis, Richard S; Filiol, M; Hardin, D; Kowalski, M; Lidman, C; Lusset, V; Mouchet, M; Mourao, A; Perlmutter, S; Ripoche, P; Schlegel, D J; Tao, C

    2007-01-01

    We present a progress report on a project to derive the evolution of the volumetric supernova Type Ia rate from the Supernova Legacy Survey. Our preliminary estimate of the rate evolution divides the sample from Neill et al. (2006) into two redshift bins: 0.2 < z < 0.4, and 0.4 < z < 0.6. We extend this by adding a bin from the sample analyzed in Sullivan et al. (2006) in the range 0.6 < z < 0.75 from the same time period. We compare the derived trend with previously published rates and a supernova Type Ia production model having two components: one component associated closely with star formation and an additional component associated with host galaxy mass. Our observed trend is consistent with this model, which predicts a rising SN Ia rate out to at least z=2.

  20. Supernova olivine from cometary dust

    Science.gov (United States)

    Messenger, Scott; Keller, Lindsay P.; Lauretta, Dante S.

    2005-01-01

    An interplanetary dust particle contains a submicrometer crystalline silicate aggregate of probable supernova origin. The grain has a pronounced enrichment in 18O/16O (13 times the solar value) and depletions in 17O/16O (one-third solar) and 29Si/28Si (olivine (forsterite 83) grains olivine grain could have formed by equilibrium condensation from cooling supernova ejecta if several different nucleosynthetic zones mixed in the proper proportions. The supernova grain is also partially encased in nitrogen-15-rich organic matter that likely formed in a presolar cold molecular cloud.

  1. Supernova Acceleration Probe: Studying Dark Energy with Type Ia Supernovae

    CERN Document Server

    Albert, J; Allam, S; Althouse, W E; Amanullah, R; Annis, J; Astier, Pierre; Aumeunier, M; Bailey, S; Baltay, C; Barrelet, E; Basa, S; Bebek, C; Bergström, L; Bernstein, G; Bester, M; Besuner, B; Bigelow, B; Blandford, R; Bohlin, R; Bonissent, A; Bower, C; Brown, M; Campbell, M; Carithers, W; Cole, D; Commins, Eugene D; Craig, W; Davis, T; Dawson, K; Day, C; De Harveng, M; De Jongh, F; Deustua, S; Diehl, H; Dobson, T; Dodelson, S; Ealet, A; Ellis, R; Emmet, W; Figer, D; Fouchez, D; Frerking, M; Frieman, J A; Fruchter, A; Gerdes, D; Gladney, L; Goldhaber, G; Goobar, A; Groom, D; Heetderks, H; Hoff, M; Holland, S; Huffer, M; Hui, L; Huterer, D; Jain, B; Jelinsky, P; Juramy, C; Karcher, A; Kent, S; Kahn, S; Kim, A; Kolbe, W; Krieger, B; Kushner, G; Kuznetsova, N; Lafever, R; Lamoureux, J; Lampton, M; Lefèvre, O; Lebrun, V; Levi, M; Limon, P; Lin, H; Linder, E; Loken, S; Lorenzon, W; Malina, R; Marian, L; Marriner, J P; Marshall, P; Massey, R; Mazure, A; McGinnis, B; McKay, T; McKee, S; Miquel, R; Mobasher, B; Morgan, N; Mortsell, E; Mostek, N; Mufson, S; Musser, J; Nakajima, R; Nugent, P; Olus, H; Pain, R; Palaio, N; Pankow, D; Peoples, John; Perlmutter, S; Peterson, D; Prieto, E; Rabinowitz, D; Réfrégier, A; Rhodes, J; Roe, N; Rusin, D; Scarpine, V; Schubnell, M; Seiffert, M; Sholl, M; Shukla, H; Smadja, G; Smith, R M; Smoot, George F; Snyder, J; Spadafora, A; Stabenau, F; Stebbins, A; Stoughton, C; Szymkowiak, A; Tarle, G; Taylor, K; Tilquin, A; Tomasch, A; Tucker, D; Vincent, D; Von der Lippe, H; Walder, J P; Wang, G; Weinstein, A; Wester, W; White, M

    2005-01-01

    The Supernova Acceleration Probe (SNAP) will use Type Ia supernovae (SNe Ia) as distance indicators to measure the effect of dark energy on the expansion history of the Universe. (SNAP's weak-lensing program is described in a companion White Paper.) The experiment exploits supernova distance measurements up to their fundamental systematic limit; strict requirements on the monitoring of each supernova's properties lead to the need for a space-based mission. Results from pre-SNAP experiments, which characterize fundamental SN Ia properties, will be used to optimize the SNAP observing strategy to yield data, which minimize both systematic and statistical uncertainties. SNAP has achieved technological readiness and the collaboration is poised to begin construction.

  2. Photometric redshifts for supernovae Ia in the Supernova Legacy Survey

    CERN Document Server

    Palanque-Delabrouille, Nathalie; Pascal, S; Rich, J; Guy, J; Bazin, G; Astier, P; Balland, C; Basa, S; Carlberg, R G; Conley, A; Fouchez, D; Hardin, D; Hook, I M; Howell, D A; Pain, R; Perrett, K; Pritchet, C J; Regnault, N; Sullivan, M

    2009-01-01

    We present a method using the SALT2 light curve fitter to determine the redshift of Type Ia supernovae in the Supernova Legacy Survey (SNLS) based on their photometry in g', r', i' and z'. On 289 supernovae of the first three years of SNLS data, we obtain a precision $\\sigma_{\\Delta z/(1+z)} = 0.022$ on average up to a redshift of 1.0, with a higher precision of 0.016 for z0.45. The rate of events with $|\\Delta z|/(1+z)>0.15$ (catastrophic errors) is 1.4%. Both the precision and the rate of catastrophic errors are better than what can be currently obtained using host galaxy photometric redshifts. Photometric redshifts of this precision may be useful for future experiments which aim to discover up to millions of supernovae Ia but without spectroscopy for most of them.

  3. Supernova 1987A: The Supernova of a Lifetime

    Science.gov (United States)

    Kirshner, Robert

    2017-01-01

    Supernova 1987A, the brightest supernova since Kepler's in 1604, was detected 30 years ago at a distance of 160 000 light years in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. Visible with the naked eye and detected with the full range of technology constructed since Kepler's time, SN 1987A has continued to be a rich source of empirical information to help understand supernova explosions and their evolution into supernova remnants. While the light output has faded by a factor of 10 000 000 over those 30 years, instrumentation, like the Hubble Space Telescope, the Chandra X-ray Observatory, and the Atacama Large Millimeter Array has continued to improve so that this supernova continues to be visible in X-rays, ultraviolet light, visible light, infrared light and in radio emission. In this review, I will sketch what has been learned from these observations about the pre-supernova star and its final stages of evolution, the explosion physics, the energy sources for emission, and the shock physics as the expanding debris encounters the circumstellar ring that was created about 20 000 years before the explosion. Today, SN 1987A is making the transition to a supernova remnant- the energetics are no longer dominated by the radioactive elements produced in the explosion, but by the interaction of the expanding debris with the surrounding gas. While we are confident that the supernova explosion had its origin in gravitational collapse, careful searches for a compact object at the center of the remnant place upper limits of a few solar luminosities on that relic. Support for HST GO programs 13401 and 13405 was provided by NASA through grants from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

  4. Magnetar-Powered Supernovae in Two Dimensions. I. Superluminous Supernovae

    OpenAIRE

    Chen, Ke-Jung; Woosley, S. E.; Sukhbold, Tuguldur

    2016-01-01

    Previous studies have shown that the radiation emitted by a rapidly rotating magnetar embedded in a young supernova can greatly amplify its luminosity. These one-dimensional studies have also revealed the existence of an instability arising from the piling up of radiatively accelerated matter in a thin dense shell deep inside the supernova. Here we examine the problem in two dimensions and find that, while instabilities cause mixing and fracture this shell into filamentary structures that red...

  5. Obituary: Harding Eugene (Gene) Smith, Jr., 1947-2007

    Science.gov (United States)

    Lonsdale, Carol; Soifer, Tom

    2009-01-01

    Harding Eugene Smith Junior, or Gene, as he was known to family, friends, and colleagues, passed away after an automobile accident in Encinitas, California, on 16 August 2007. He was 60 years old. Gene had recently retired from UCSD after thirty years of service. A memorial service was held at Quail Botanical Gardens in Encinitas, California, on 23 August 2007. A web page is dedicated to his memory at http://harding.smith.muchloved.com, where contributions of memories are invited. Gene was born in San Jose, California in 1947, to Harding Eugene Smith Senior, and Bernice Smith (nee Smith). Harding Smith Senior was an air-force navigator; therefore Gene spent his childhood moving from one air-force base to another. Although an only child, Gene was very close to his cousin Meg, whom he lived nearby to in Gilroy for a time, and the two were like brother and sister. The elder Harding Smith was lost in action over Cambodia in the mid-sixties. Gene was a dedicated student, a boy scout, and a Presidential Scholar. He majored in Physics at Caltech, where he also took a lively interest in the football team and the Glee Club, and was elected a House Officer. To his close friends, he was known at Caltech as Smitty, and the closest of them was Rob Drew, who gave a glimpse into that period of Gene's life at the memorial: "Gene arrived early at campus his first year, in response to an invitation to join the football team. Gene's size and features reminded the head coach of a long-forgotten player named 'Johnson.' After a few days of confusion, Gene simply replaced the name on his helmet. 'Johnson!' coach would yell, 'get in there!' If Johnson was going to get to play, Gene was going to be the best Johnson available!" Gene spent the summer of 1966 working at Kitt Peak, where his lifetime love of observing with ground-based telescopes began, though he learned some things the hard way, such as the fact that trying to squeeze 40,000 numbers onto a computer that stored only 32

  6. Breeding productivity of Smith Island black ducks

    Science.gov (United States)

    Haramis, G.M.; Jorde, D.G.; Olsen, G.H.; Stotts, D.B.; Harrison, M.K.; Perry, M.C.

    2002-01-01

    We investigated the breeding performance of American black ducks (Anas rubripes) on Smith Island, Chesapeake Bay, to improve our understanding of island black duck breeding ecology and to make management recommendations to enhance productivity. During 1995-96, we implanted 56 female black ducks with 20-g radio transmitters and tracked 35 of the individuals through the breeding season to locate nests, determine nest fate, and identify brood habitat. We also increased preseason banding efforts and compared capture characteristics over 12 years with those from the Deal Island Wildlife Management Area, a banding site on the mainland of Tangier Sound. A low rate of nesting (37%), lack of renesting, and poor hatching success (31%) indicated that island salt marsh habitats present a harsh environment for breeding black ducks. Black ducks located 11 of 13 nests (85%) in black needlerush (Juncus roemerianus) marsh where they were vulnerable to flooding from extreme tides and to egg predators. No nests were found on forested tree hammocks, a feature that distinguishes Smith Island from nearby South Marsh and Bloodsworth Islands. Nest predators included red foxes (Vulpes vulpes), herring gulls (Larus argentams), fish crows (Corvus ossifragus), and, potentially, Norway rats (Rattus norvegicus). Unlike mainland red foxes, foxes radio tracked on Smith Island were found to be capable swimmers and effective low marsh predators. We found shoreline meadows of widgeon grass (Ruppia maritima) to be important foraging sites for black ducks and suspected that the virtual absence of fresh water in this high salinity environment (1217+ ppt) to incur some cost in terms of growth and survival of ducklings. Preseason bandings revealed a high proportion of banded adults and a strong positive correlation in age ratios with the Deal Island banding site. This latter finding strongly suggests a negative universal effect of storm tides on nest success for Tangier Sound black ducks. Management to

  7. Verlossing: van Pelagius tot Joseph Smith

    Directory of Open Access Journals (Sweden)

    H.F. van Wyk

    2010-07-01

    Full Text Available Salvation: from Pelagius to Joseph Smith Every Christian church believes that she is a true church and proclaims that man can be saved and has eternal life. This dogma of salvation is usually based on the Bible as the Word of God. Mormons claim that Joseph Smith, founder and first president of the Church of Jesus Christ of Latter Day Saints, received a divine message to restore the church that Jesus had started.  In studying the plan of salvation the Mormons proclaim it is quite clear that that way of salvation was not restored in their church, but that it followed a pattern of false doctrine that was revealed time and again in history.  The core of their preaching of salvation is that man has the free will to choose his own salvation. Mormons are not the first to preach this message. This article will show that Pelagius oisty-kated the free will of man. In the Reformation the Anabaptists preached the same message, being a third movement next to the reformed and Roman Catholic believes. The Anabaptists became part of the churches of the Netherlands and at the Synod of Dordt the theology of the free will was rejected and answered.  The dogma of the free will of man did not end at this Synod: 150 years later John Wesley preached the same message of salvation during his and Whitefield’s campaigns at the dawn of the nineteenth century in the USA.  During this time Joseph Smith started to seek the true church and founded the Mormon Church. Although his theology differs quite strongly from the Methodist Church in which he grew up, the core of the way of salvation is the same: man has free will in choosing his salvation.

  8. The Vela Supernova Remnant

    Science.gov (United States)

    Raymond, John C.

    We wish to obtain both emission and absorption line observations of the Vela Supernova remnant. The filament we wish to study in emission is the brightest filament in the SNR, so it will provide a spectrum twice the quality of any in existence. It is also located at the edge of an unusual bulge in the SNR, and it can be used to test the level of departure from pressure equilibrium in the remnant, which is useful as a test of evaporative models of SNR evolution. The absorption line studies will look for evidence of the drastically unstable behavior of shocks above 150 km/s predicted by Innes and Giddings. Four of the stars studied by Jenkins, Silk and Wallerstein showed marginal evidence for two positive or two negative high velocity components. If these multiple velocity components are confirmed, they support the secondary shock predictions of Innes and Giddings.

  9. Neutrinos and nucleosynthesis in supernova

    Energy Technology Data Exchange (ETDEWEB)

    Solis, U [Instituto de Ciencias Nucleares, Departamento de Fisica de Altas EnergIas, Universidad Nacional Autonoma de Mexico (ICN-UNAM). Apartado Postal 70-543, 04510 Mexico, D.F. (Mexico); D' Olivo, J C [Instituto de Ciencias Nucleares, Departamento de Fisica de Altas EnergIas, Universidad Nacional Autonoma de Mexico (ICN-UNAM). Apartado Postal 70-543, 04510 Mexico, D.F. (Mexico); Cabral-Rosetti, L G [Departamento de Posgrado, Centro Interdisciplinario de Investigacion y Docencia en Educacion Tecnica (CIIDET), Av. Universidad 282 Pte., Col. Centro, A. Postal 752, C.P. 76000, Santiago de Queretaro, Qro. (Mexico)

    2006-05-15

    The type II supernova is considered as a candidate site for the production of heavy elements. The nucleosynthesis occurs in an intense neutrino flux, we calculate the electron fraction in this environment.

  10. The Diffuse Supernova Neutrino Background

    CERN Document Server

    Beacom, John F

    2010-01-01

    The Diffuse Supernova Neutrino Background (DSNB) is the weak glow of MeV neutrinos and antineutrinos from distant core-collapse supernovae. The DSNB has not been detected yet, but the Super-Kamiokande (SK) 2003 upper limit on the electron antineutrino flux is close to predictions, now quite precise, based on astrophysical data. If SK is modified with dissolved gadolinium to reduce detector backgrounds and increase the energy range for analysis, then it should detect the DSNB at a rate of a few events per year, providing a new probe of supernova neutrino emission and the cosmic core-collapse rate. If the DSNB is not detected, then new physics will be required. Neutrino astronomy, while uniquely powerful, has proven extremely difficult -- only the Sun and the nearby Supernova 1987A have been detected to date -- so the promise of detecting new sources soon is exciting indeed.

  11. Toward a Standard Model of Core Collapse Supernovae

    OpenAIRE

    Mezzacappa, A.

    2000-01-01

    In this paper, we discuss the current status of core collapse supernova models and the future developments needed to achieve significant advances in understanding the supernova mechanism and supernova phenomenology, i.e., in developing a supernova standard model.

  12. Supernovae and Gamma Ray Bursts

    Directory of Open Access Journals (Sweden)

    M. Della Valle

    2007-01-01

    Full Text Available Se revisa el estatus observacional de la conexi on Supernova (SN/Estallido de Rayos-Gamma (GRB. Recientes (y no tan recientes observaciones de GRBs largos sugieren que una fracci on signi cativa de ellos (pero no todos est an asociados con supernovas brillantes del tipo Ib/c. Estimaciones actuales de las tasas de producci on de GRBs y SNs dan una raz on para GRB/SNe-Ibc en el rango 0:4%

  13. Kiso Supernova Survey (KISS): Survey Strategy

    CERN Document Server

    Morokuma, Tomoki; Tanaka, Masaomi; Mori, Kensho; Matsumoto, Emiko; Kikuchi, Yuki; Shibata, Takumi; Sako, Shigeyuki; Aoki, Tsutomu; Doi, Mamoru; Kobayashi, Naoto; Maehara, Hiroyuki; Matsunaga, Noriyuki; Mito, Hiroyuki; Miyata, Takashi; Nakada, Yoshikazu; Soyano, Takao; Tarusawa, Ken'ichi; Miyazaki, Satoshi; Nakata, Fumiaki; Okada, Norio; Sarugaku, Yuki; Richmond, Michael W; Akitaya, Hiroshi; Aldering, Greg; Arimatsu, Ko; Contreras, Carlos; Horiuchi, Takashi; Hsiao, Eric Y; Itoh, Ryosuke; Iwata, Ikuru; Koji,; Kawabata, S; Kawai, Nobuyuki; Kitagawa, Yutaro; Kokubo, Mitsuru; Kuroda, Daisuke; Paolo,; Mazzali,; Misawa, Toru; Moritani, Yuki; Morrell, Nidia; Okamoto, Rina; Pavlyuk, Nikolay; Phillips, Mark M; Pian, Elena; Sahu, Devendra; Saito, Yoshihiko; Sano, Kei; Stritzinger, Maximilian D; Tachibana, Yutaro; Taddia, Francesco; Takaki, Katsutoshi; Tateuchi, Ken; Tomita, Akihiko; Tsvetkov, Dmitry; Ui, Takahiro; Ukita, Nobuharu; Urata, Yuji; Walker, Emma S; Yoshii, Taketoshi

    2014-01-01

    The Kiso Supernova Survey (KISS) is a high-cadence optical wide-field supernova (SN) survey. The primary goal of the survey is to catch the very early light of a SN, during the shock breakout phase. Detection of SN shock breakouts combined with multi-band photometry obtained with other facilities would provide detailed physical information on the progenitor stars of SNe. The survey is performed using a 2.2x2.2 deg field-of-view instrument on the 1.05-m Kiso Schmidt telescope, the Kiso Wide Field Camera (KWFC). We take a three-minute exposure in g-band once every hour in our survey, reaching magnitude g~20-21. About 100 nights of telescope time per year have been spent on the survey since April 2012. The number of the shock breakout detections is estimated to be of order of 1 during our 3-year project. This paper summarizes the KISS project including the KWFC observing setup, the survey strategy, the data reduction system, and CBET-reported SNe discovered so far by KISS.

  14. Kiso Supernova Survey (KISS): Survey strategy

    Science.gov (United States)

    Morokuma, Tomoki; Tominaga, Nozomu; Tanaka, Masaomi; Mori, Kensho; Matsumoto, Emiko; Kikuchi, Yuki; Shibata, Takumi; Sako, Shigeyuki; Aoki, Tsutomu; Doi, Mamoru; Kobayashi, Naoto; Maehara, Hiroyuki; Matsunaga, Noriyuki; Mito, Hiroyuki; Miyata, Takashi; Nakada, Yoshikazu; Soyano, Takao; Tarusawa, Ken'ichi; Miyazaki, Satoshi; Nakata, Fumiaki; Okada, Norio; Sarugaku, Yuki; Richmond, Michael W.; Akitaya, Hiroshi; Aldering, Greg; Arimatsu, Ko; Contreras, Carlos; Horiuchi, Takashi; Hsiao, Eric Y.; Itoh, Ryosuke; Iwata, Ikuru; Kawabata, Koji S.; Kawai, Nobuyuki; Kitagawa, Yutaro; Kokubo, Mitsuru; Kuroda, Daisuke; Mazzali, Paolo; Misawa, Toru; Moritani, Yuki; Morrell, Nidia; Okamoto, Rina; Pavlyuk, Nikolay; Phillips, Mark M.; Pian, Elena; Sahu, Devendra; Saito, Yoshihiko; Sano, Kei; Stritzinger, Maximilian D.; Tachibana, Yutaro; Taddia, Francesco; Takaki, Katsutoshi; Tateuchi, Ken; Tomita, Akihiko; Tsvetkov, Dmitry; Ui, Takahiro; Ukita, Nobuharu; Urata, Yuji; Walker, Emma S.; Yoshii, Taketoshi

    2014-12-01

    The Kiso Supernova Survey (KISS) is a high-cadence optical wide-field supernova (SN) survey. The primary goal of the survey is to catch the very early light of a SN, during the shock breakout phase. Detection of SN shock breakouts combined with multi-band photometry obtained with other facilities would provide detailed physical information on the progenitor stars of SNe. The survey is performed using a 2.2° × 2.2° field-of-view instrument on the 1.05-m Kiso Schmidt telescope, the Kiso Wide Field Camera (KWFC). We take a 3-min exposure in g-band once every hour in our survey, reaching magnitude g ˜ 20-21. About 100 nights of telescope time per year have been spent on the survey since 2012 April. The number of the shock breakout detections is estimated to be of the order of 1 during our three-year project. This paper summarizes the KISS project including the KWFC observing setup, the survey strategy, the data reduction system, and CBET-reported SNe discovered so far by KISS.

  15. Ozone Depletion from Nearby Supernovae

    CERN Document Server

    Gehrels, N; Jackman, C H; Cannizzo, J K; Mattson, B J; Chen, W; Gehrels, Neil; Laird, Claude M.; Jackman, Charles H.; Cannizzo, John K.; Mattson, Barbara J.; Chen, Wan

    2003-01-01

    Estimates made in the 1970's indicated that a supernova occurring within tens of parsecs of Earth could have significant effects on the ozone layer. Since that time, improved tools for detailed modeling of atmospheric chemistry have been developed to calculate ozone depletion, and advances have been made in theoretical modeling of supernovae and of the resultant gamma-ray spectra. In addition, one now has better knowledge of the occurrence rate of supernovae in the galaxy, and of the spatial distribution of progenitors to core-collapse supernovae. We report here the results of two-dimensional atmospheric model calculations that take as input the spectral energy distribution of a supernova, adopting various distances from Earth and various latitude impact angles. In separate simulations we calculate the ozone depletion due to both gamma-rays and cosmic rays. We find that for the combined ozone depletion roughly to double the ``biologically active'' UV flux received at the surface of the Earth, the supernova mu...

  16. Ozone Depletion from Nearby Supernovae

    Science.gov (United States)

    Gehrels, Neil; Laird, Claude M.; Jackman, Charles H.; Cannizzo, John K.; Mattson, Barbara J.; Chen, Wan; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    Estimates made in the 1970's indicated that a supernova occurring within tens of parsecs of Earth could have significant effects on the ozone layer. Since that time improved tools for detailed modeling of atmospheric chemistry have been developed to calculate ozone depletion, and advances have been made also in theoretical modeling of supernovae and of the resultant gamma ray spectra. In addition, one now has better knowledge of the occurrence rate of supernovae in the galaxy, and of the spatial distribution of progenitors to core-collapse supernovae. We report here the results of two-dimensional atmospheric model calculations that take as input the spectral energy distribution of a supernova, adopting various distances from Earth and various latitude impact angles. In separate simulations we calculate the ozone depletion due to both gamma rays and cosmic rays. We find that for the combined ozone depletion from these effects roughly to double the 'biologically active' UV flux received at the surface of the Earth, the supernova must occur at approximately or less than 8 parsecs.

  17. 76 FR 60733 - Drawbridge Operation Regulations; Narrow Bay, Smith Point, NY

    Science.gov (United States)

    2011-09-30

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Narrow Bay, Smith Point, NY AGENCY... the Smith Point Bridge, 6.1, across Narrow Bay, between Smith Point and Fire Island, New York. The.... SUPPLEMENTARY INFORMATION: The Smith Point Bridge, across Narrow Bay, mile 6.1, between Smith Point and...

  18. Exploring the Physics of Type Ia Supernovae Through the X-ray Spectra of their Remnants

    CERN Document Server

    Badenes, C; Bravo, E; Hughes, J P; Hwang, U

    2005-01-01

    We present the results of an ongoing project to use the X-ray observations of Type Ia Supernova Remnants to constrain the physical processes involved in Type Ia Supernova explosions. We use the Tycho Supernova Remnant (SN 1572) as a benchmark case, comparing its observed spectrum with models for the X-ray emission from the shocked ejecta generated from different kinds of Type Ia explosions. Both the integrated spectrum of Tycho and the spatial distribution of the Fe and Si emission in the remnant are well reproduced by delayed detonation models with stratified ejecta. All the other Type Ia explosion models fail, including well-mixed deflagrations calculated in three dimensions.

  19. The Nearby Supernova Factory: Toward A High-Precision Spectro-Photometry

    Energy Technology Data Exchange (ETDEWEB)

    Nearby Supernova Factory; Copin, Y.; Buton, C.; Gangler, E.; Smadja, G.; Pecontal, E.; Rigaudier, G.; Antilogus, P.; Bailey, S.; Pain, R.; Pereira, R.; Wu, C.; Aldering, G.; Aragon, C.; Bongard, S.; Childress, M.; Loken, S.; Nugent, P.; Perlmutter, S.; Runge, K.; Thomas, R.; Weaver, B.; Baltay, C.; Bauer, A.; Rabinowitz, D.; Scalzo, R.

    2007-07-01

    The Nearby Supernova Factory (SNfactory) is an international project to discover and study a large sample of type Ia supernovae in the redshift range 0.03 < z < 0.08. Follow-up spectro-photometric observations are performed using the dedicated Supernovae Integral-Field Spectrograph, mounted since 2004 on 2.2 m UH telescope. The goal is to acquire for each supernova and over its full life-time (more than 10 epochs) high spectro-photometric quality spectra over the extended optical range (320-1000 nm).I will present the current status of the SNfactory project, from search efficiency to first scientific results, with an emphasis on the spectro-photometric calibration issues and achievements.

  20. How Bright Can Supernovae Get?

    Science.gov (United States)

    Kohler, Susanna

    2016-04-01

    Supernovae enormous explosions associated with the end of a stars life come in a variety of types with different origins. A new study has examined how the brightest supernovae in the Universe are produced, and what limits might be set on their brightness.Ultra-Luminous ObservationsRecent observations have revealed many ultra-luminous supernovae, which haveenergies that challenge our abilities to explain them usingcurrent supernova models. An especially extreme example is the 2015 discovery of the supernova ASASSN-15lh, which shone with a peak luminosity of ~2*1045 erg/s, nearly a trillion times brighter than the Sun. ASASSN-15lh radiated a whopping ~2*1052 erg in the first four months after its detection.How could a supernova that bright be produced? To explore the answer to that question, Tuguldur Sukhbold and Stan Woosley at University of California, Santa Cruz, have examined the different sources that could produce supernovae and calculated upper limits on the potential luminosities ofeach of these supernova varieties.Explosive ModelsSukhbold and Woosley explore multiple different models for core-collapse supernova explosions, including:Prompt explosionA stars core collapses and immediately explodes.Pair instabilityElectron/positron pair production at a massive stars center leads to core collapse. For high masses, radioactivity can contribute to delayed energy output.Colliding shellsPreviously expelled shells of material around a star collide after the initial explosion, providing additional energy release.MagnetarThe collapsing star forms a magnetar a rapidly rotating neutron star with an incredibly strong magnetic field at its core, which then dumps energy into the supernova ejecta, further brightening the explosion.They then apply these models to different types of stars.Setting the LimitThe authors show that the light curve of ASASSN-15lh (plotted in orange) can be described by a model (black curve) in which a magnetar with an initial spin period of 0.7 ms

  1. The ESSENCE Supernova Survey: Survey Optimization, Observations, and Supernova Photometry

    Energy Technology Data Exchange (ETDEWEB)

    Miknaitis, Gajus; Pignata, G.; Rest, A.; Wood-Vasey, W.M.; Blondin, S.; Challis, P.; Smith, R.C.; Stubbs, C.W.; Suntzeff, N.B.; Foley, R.J.; Matheson, T.; Tonry, J.L.; Aguilera, C.; Blackman, J.W.; Becker, A.C.; Clocchiatti, A.; Covarrubias, R.; Davis, T.M.; Filippenko, A.V.; Garg, A.; Garnavich, P.M.; /Fermilab /Chile U., Catolica /Cerro-Tololo

    2007-01-08

    We describe the implementation and optimization of the ESSENCE supernova survey, which we have undertaken to measure the equation of state parameter of the dark energy. We present a method for optimizing the survey exposure times and cadence to maximize our sensitivity to the dark energy equation of state parameter w = P/{rho}c{sup 2} for a given fixed amount of telescope time. For our survey on the CTIO 4m telescope, measuring the luminosity distances and redshifts for supernovae at modest redshifts (z {approx} 0.5 {+-} 0.2) is optimal for determining w. We describe the data analysis pipeline based on using reliable and robust image subtraction to find supernovae automatically and in near real-time. Since making cosmological inferences with supernovae relies crucially on accurate measurement of their brightnesses, we describe our efforts to establish a thorough calibration of the CTIO 4m natural photometric system. In its first four years, ESSENCE has discovered and spectroscopically confirmed 102 type Ia SNe, at redshifts from 0.10 to 0.78, identified through an impartial, effective methodology for spectroscopic classification and redshift determination. We present the resulting light curves for the all type Ia supernovae found by ESSENCE and used in our measurement of w, presented in Wood-Vasey et al. (2007).

  2. Supernova Remnant in 3-D

    Science.gov (United States)

    2009-01-01

    of the wavelength shift is related to the speed of motion, one can determine how fast the debris are moving in either direction. Because Cas A is the result of an explosion, the stellar debris is expanding radially outwards from the explosion center. Using simple geometry, the scientists were able to construct a 3-D model using all of this information. A program called 3-D Slicer modified for astronomical use by the Astronomical Medicine Project at Harvard University in Cambridge, Mass. was used to display and manipulate the 3-D model. Commercial software was then used to create the 3-D fly-through. The blue filaments defining the blast wave were not mapped using the Doppler effect because they emit a different kind of light synchrotron radiation that does not emit light at discrete wavelengths, but rather in a broad continuum. The blue filaments are only a representation of the actual filaments observed at the blast wave. This visualization shows that there are two main components to this supernova remnant: a spherical component in the outer parts of the remnant and a flattened (disk-like) component in the inner region. The spherical component consists of the outer layer of the star that exploded, probably made of helium and carbon. These layers drove a spherical blast wave into the diffuse gas surrounding the star. The flattened component that astronomers were unable to map into 3-D prior to these Spitzer observations consists of the inner layers of the star. It is made from various heavier elements, not all shown in the visualization, such as oxygen, neon, silicon, sulphur, argon and iron. High-velocity plumes, or jets, of this material are shooting out from the explosion in the plane of the disk-like component mentioned above. Plumes of silicon appear in the northeast and southwest, while those of iron are seen in the southeast and north. These jets were already known and Doppler velocity measurements have been made for these structures, but their orientation and

  3. Oscar F. Smith Middle School: One Extra Degree

    Science.gov (United States)

    Principal Leadership, 2012

    2012-01-01

    This article features Oscar F. Smith Middle School, a challenging school in Chesapeake, Virginia. When Principal Linda Scott exclaims, "Oscar F. Smith Middle School is "hot"!" to visitors, she is not referring to the inside temperature of the bustling school of grades 6-8 located in the historic South Norfolk borough of…

  4. Father Knows Best: Using Adam Smith to Teach Transactions Costs

    Science.gov (United States)

    Dupont, Brandon

    2014-01-01

    Adam Smith's moral philosophy can be used to introduce economics students to the important idea of transactions costs. The author provides a brief background in this article to Smith's moral philosophy and connects it to the costs of transacting in a way that fits easily into the standard principles of microeconomics classroom. By doing…

  5. Author! Author! The Gallant Children's Author: Dick King-Smith

    Science.gov (United States)

    Brodie, Carolyn S.

    2005-01-01

    This column presents a brief biography of Dick King-Smith. Born on March 27, 1922 and raised in Gloucestershire, England, he grew up with animals of all kinds. King-Smith was a farmer for twenty years and then became a school teacher. He was also a soldier during wartime, a traveling salesman, shoe factory worker, and television presenter. He…

  6. Father Knows Best: Using Adam Smith to Teach Transactions Costs

    Science.gov (United States)

    Dupont, Brandon

    2014-01-01

    Adam Smith's moral philosophy can be used to introduce economics students to the important idea of transactions costs. The author provides a brief background in this article to Smith's moral philosophy and connects it to the costs of transacting in a way that fits easily into the standard principles of microeconomics classroom. By doing…

  7. Light-echo spectroscopy of historic Supernovae

    Science.gov (United States)

    Krause, Oliver

    Young Galactic supernova remnants are unique laboratories for supernova physics. Due to their proximity they provide us with the most detailed view of the outcome of a supernova. However, the exact spectroscopic types of their original explosions have been undetermined so far -hindering to link the wealth of multi-wavelength knowledge about their remnants with the diverse population of supernovae. Light echoes, reflektions of the brilliant supernova burst of light by interstellar dust, provide a unique opportunity to reobserve today -with powerful scientific instruments of the 21st century -historic supernova exlosions even after hundreds of years and to conclude on their nature. We report on optical light-echo spectroscopy of two famous Galactic supernovae: Tycho Brahe's SN 1572 and the supernova that created the Cassiopeia A remnant around the year 1680. These observations finally recovered the missing spectroscopic classifications and provide new constraints on explosion models for future studies.

  8. BENTUK NORMAL SMITH DAN MATRIKS BAIK KIRI/KANAN

    Directory of Open Access Journals (Sweden)

    Yumiati Yumiati

    2016-09-01

    Full Text Available The Smith normal form and left good matrix have been known in matrix theorem. Any matrix over the principal ideal ring has a Smith normal form. The Smith normal form of a matrix has many applications on various fields such as a solution of Diophantin linear equation and differential equation system. Furthermore, a matrix A with entries in a commutative ring R with unity is left good if for every vector x, the ideal áxAñ is the same as the ideal áAñ. This paper discusses the relation between the Smith normal form and left good matrix. The relation is as the following: matrix A with entries in principal ideal ring of size m by n, with m < n, has Smith normal form [Im, O] if only if A is a left good matrix.

  9. Supernova Physics at DUNE

    CERN Document Server

    Ankowski, Artur; Benhar, Omar; Chen, Sun; Cherry, John; Cui, Yanou; Friedland, Alexander; Gil-Botella, Ines; Haghighat, Alireza; Horiuchi, Shunsaku; Huber, Patrick; Kneller, James; Laha, Ranjan; Li, Shirley; Link, Jonathan; Lovato, Alessandro; Macias, Oscar; Mariani, Camillo; Mezzacappa, Anthony; O'Connor, Evan; O'Sullivan, Erin; Rubbia, Andre; Scholberg, Kate; Takeuchi, Tatsu

    2016-01-01

    The DUNE/LBNF program aims to address key questions in neutrino physics and astroparticle physics. Realizing DUNE's potential to reconstruct low-energy particles in the 10-100 MeV energy range will bring significant benefits for all DUNE's science goals. In neutrino physics, low-energy sensitivity will improve neutrino energy reconstruction in the GeV range relevant for the kinematics of DUNE's long-baseline oscillation program. In astroparticle physics, low-energy capabilities will make DUNE's far detectors the world's best apparatus for studying the electron-neutrino flux from a supernova. This will open a new window to unrivaled studies of the dynamics and neutronization of a star's central core in real time, the potential discovery of the neutrino mass hierarchy, provide new sensitivity to physics beyond the Standard Model, and evidence of neutrino quantum-coherence effects. The same capabilities will also provide new sensitivity to `boosted dark matter' models that are not observable in traditional direc...

  10. A Supernova's Shockwaves

    Science.gov (United States)

    2007-01-01

    Supernovae are the explosive deaths of the universe's most massive stars. In death, these volatile creatures blast tons of energetic waves into the cosmos, destroying much of the dust surrounding them. This false-color composite from NASA's Spitzer Space Telescope and NASA's Chandra X-ray Observatory shows the remnant of one such explosion. The remnant, called N132D, is the wispy pink shell of gas at the center of this image. The pinkish color reveals a clash between the explosion's high-energy shockwaves and surrounding dust grains. In the background, small organic molecules called polycyclic aromatic hydrocarbons are shown as tints of green. The blue spots represent stars in our galaxy along this line of sight. N132D is located 163,000 light-years away in a neighboring galaxy called, the Large Magellanic Cloud. In this image, infrared light at 4.5 microns is mapped to blue, 8.0 microns to green and 24 microns to red. Broadband X-ray light is mapped purple. The infrared data were taken by Spitzer's infrared array camera and multiband imaging photometer, while the X-ray data were captured by Chandra.

  11. The Shape of Superluminous Supernovae

    Science.gov (United States)

    Kohler, Susanna

    2016-11-01

    What causes the tremendous explosions of superluminous supernovae? New observations reveal the geometry of one such explosion, SN 2015bn, providing clues as to its source.A New Class of ExplosionsImage of a type Ia supernova in the galaxy NGC 4526. [NASA/ESA]Supernovae are powerful explosions that can briefly outshine the galaxies that host them. There are several different classifications of supernovae, each with a different physical source such as thermonuclear instability in a white dwarf, caused by accretion of too much mass, or the exhaustion of fuel in the core of a massive star, leading to the cores collapse and expulsion of its outer layers.In recent years, however, weve detected another type of supernovae, referred to as superluminous supernovae. These particularly energetic explosions last longer months instead of weeks and are brighter at their peaks than normal supernovae by factors of tens to hundreds.The physical cause of these unusual explosions is still a topic of debate. Recently, however, a team of scientists led by Cosimo Inserra (Queens University Belfast) has obtained new observations of a superluminous supernova that might help address this question.The flux and the polarization level (black lines) along the dominant axis of SN 2015bn, 24 days before peak flux (left) and 28 days after peak flux (right). Blue lines show the authors best-fitting model. [Inserra et al. 2016]Probing GeometryInserra and collaborators obtained two sets of observations of SN 2015bn one roughly a month before and one a month after the superluminous supernovas peak brightness using a spectrograph on the Very Large Telescope in Chile. These observations mark the first spectropolarimetric data for a superluminous supernova.Spectropolarimetry is the practice of obtaining information about the polarization of radiation from an objects spectrum. Polarization carries information about broken spatial symmetries in the object: only if the object is perfectly symmetric can it

  12. Trinucleotide repeat expansion and DRPLA (Smith`s disease): Molecular characterization of atrophin-1

    Energy Technology Data Exchange (ETDEWEB)

    Margolis, R.L.; Li, S.H.; Li, X.J.; Ross, C.A. [Johns Hopkins Univ., Balitmore, MD (United States)

    1994-09-01

    Smith`s disease (also known as dentatorubral pallidoluysian atrophy or DRPLA) is a rare, progressive, fatal neuropsychiatric disorder similar to Huntington`s disease (HD). Smith`s disease is characterized by ataxia, choreoathetosis, myoclonic epilepsy, dementia, and genetic anticipation. Neuropathological findings include prominent cell loss in the dentate nucleus of the cerebellum, the globus pallidus, the red nucleus, and the subthalamic nucleus. An expansion of a CAG trinucleotide repeat encoding polyglutamine in a gene originally identified in our laboratory as part of a program to clone candidate genes for disorders with anticipation has recently been found to cause this disorder. We have identified two families that demonstrate the pathological and genetic features (expanded CAG repeat and anticipation) of this disease. Northern analysis indicates that the gene, which we have termed atrophin-1, is widely expressed as a 5 kb mRNA in normal human brain and peripheral tissues. Brain expression is highest in the cerebellum. The developmental expression of the rat homologues of IT-15 (the gene in which a CAG expansion causes HD) and atrophin-1 were compared. Atrophin-1 was most highly expressed in early rat embryo brain (E16), whereas the greatest expression of IT-15 was in the adult rat brain. Cloning and sequencing of the open reading frame from inserts contained in brain cDNA libraries is in progress. In addition to the CAG repeat, the ORF contains an unusual region of alternating acidic and basic amino acids. Further characterization of atrophin-1, and comparison of it to other genes in which trinucleotide repeat expansion leads to neuropsychiatric disorders, should lead to a better understanding of the pathophysiology by which CAG repeat expansion causes human disease.

  13. Bronze-Smiths of Pylos and Silver-Smiths of Ur

    OpenAIRE

    Uchitel, Alexander

    1990-01-01

    The Pylian tablets marked by the ideogram AES and classified as the Jn series can be subdivided into two subseries dealing respectively with the delivery of bronze from various places to the central authority (Jn 829, 881), and with the distribution of bronze to individual smiths (all the rest). The latter is a unique group of texts, unparalleled in other Mycenaean archives, which provides highly detailed information about the organization of this particular craft in the Kingdom of Pylos.

  14. The Process of Building the Gene Smith Tibetology Literature Center at the Southwest University for Nationalities

    Institute of Scientific and Technical Information of China (English)

    YIXI Lamu; LIU Yong; BENG Jia

    2014-01-01

    The Tibetan Buddhist Resource Center ( TBRC) founded by Gene Smith , is a non-profit organization which concentrates on collec-ting, sorting, and digitizing Tibetan literature . Most of the documents comes from Gene Smith ’ s personal collection , and the content covers reli-gion, philosophy, medicine, arts, psychology, as-trology, poetics, and history, etc.The digitali-zation of Tibetan literature and putting them on line is the key project of the institute .The purpose of the Ethnic Literature Center in the Southwest Uni-versity for Nationalities ( SWUN) is to rescue and preserve the ancient manuscripts of the ethnic groups , and there is a Tibetan Literature Section in the center .

  15. Smith Newton Vehicle Performance Evaluation - Gen2 - 1Q2014 (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-04-01

    The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory is evaluating and documenting the performance of electric and plug-in hybrid electric drive systems in medium-duty trucks across the nation. U.S. companies participating in this evaluation project received funding from the American Recovery and Reinvestment Act to cover part of the cost of purchasing these vehicles. Through this project, Smith Electric Vehicles is building and deploying 500 all-electric medium-duty trucks that will be deployed by a variety of companies in diverse climates across the country.

  16. Smith Newton Vehicle Performance Evaluation – 4th Quarter 2013; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-01-01

    The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory is evaluating and documenting the performance of electric and plug-in hybrid electric drive systems in medium-duty trucks across the nation. U.S. companies participating in this evaluation project received funding from the American Recovery and Reinvestment Act to cover part of the cost of purchasing these vehicles. Through this project, Smith Electric Vehicles is building and deploying 500 all-electric medium-duty trucks that will be deployed by a variety of companies in diverse climates across the country.

  17. Smith Newton Vehicle Performance Evaluation – Gen 2 – Cumulative; Energy Efficiency & Renewable Energy (EERE)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-10-01

    The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory is evaluating and documenting the performance of electric and plug-in hybrid electric drive systems in medium-duty trucks across the nation. U.S. companies participating in this evaluation project received funding from the American Recovery and Reinvestment Act to cover part of the cost of purchasing these vehicles. Through this project, Smith Electric Vehicles is building and deploying 500 all-electric medium-duty trucks that will be deployed by a variety of companies in diverse climates across the country.

  18. Berkeley Lab's Saul Perlmutter wins E.O. Lawrence Award; scientist's work on supernovae reveals accelerating Universe

    CERN Multimedia

    2002-01-01

    Saul Perlmutter, from Lawrence Berkeley National Laboratory Physics Division and leader of the Supernova Cosmology Project based there, has won the DOE's 2002 E.O. Lawrence Award in the physics category (2 pages).

  19. Characterising Dark Energy through supernovae

    CERN Document Server

    Davis, Tamara M

    2016-01-01

    Type Ia supernovae are a powerful cosmological probe, that gave the first strong evidence that the expansion of the universe is accelerating. Here we provide an overview of how supernovae can go further to reveal information about what is causing the acceleration, be it dark energy or some modification to our laws of gravity. We first summarise the many different approaches used to explain or test the acceleration, including parametric models (like the standard model, LambdaCDM), non-parametric models, dark fluid models such as quintessence, and extensions to standard gravity. We also show how supernova data can be used beyond the Hubble diagram, to give information on gravitational lensing and peculiar velocities that can be used to distinguish between models that predict the same expansion history. Finally, we review the methods of statistical inference that are commonly used, making a point of separating parameter estimation from model selection.

  20. Featured Image: Modeling Supernova Remnants

    Science.gov (United States)

    Kohler, Susanna

    2016-05-01

    This image shows a computer simulation of the hydrodynamics within a supernova remnant. The mixing between the outer layers (where color represents the log of density) is caused by turbulence from the Rayleigh-Taylor instability, an effect that arises when the expanding core gas of the supernova is accelerated into denser shell gas. The past standard for supernova-evolution simulations was to perform them in one dimension and then, in post-processing, manually smooth out regions that undergo Rayleigh-Taylor turbulence (an intrinsically multidimensional effect). But in a recent study, Paul Duffell (University of California, Berkeley) has explored how a 1D model could be used to reproduce the multidimensional dynamics that occur in turbulence from this instability. For more information, check out the paper below!CitationPaul C. Duffell 2016 ApJ 821 76. doi:10.3847/0004-637X/821/2/76

  1. Dynamics of Kepler's supernova remnant

    Science.gov (United States)

    Borkowski, Kazimierz J.; Blondin, John M.; Sarazin, Craig L.

    1992-01-01

    Observations of Kepler's SNR have revealed a strong interaction with the ambient medium, far in excess of that expected at a distance of about 600 pc away from the Galactic plane where Kepler's SNR is located. This has been interpreted as a result of the interaction of supernova ejecta with the dense circumstellar medium (CSM). Based on the bow-shock model of Bandiera (1985), we study the dynamics of this interaction. The CSM distribution consists of an undisturbed stellar wind of a moving supernova progenitor and a dense shell formed in its interaction with a tenuous interstellar medium. Supernova ejecta drive a blast wave through the stellar wind which splits into the transmitted and reflected shocks upon hitting this bow-shock shell. We identify the transmitted shock with the nonradiative, Balmer-dominated shocks found recently in Kepler's SNR. The transmitted shock most probably penetrated the shell in the vicinity of the stagnation point.

  2. How to Find More Supernovae with Less Work: Object ClassificationTechniques for Difference Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, Stephen; Aragon, Cecilia; Romano, Raquel; Thomas, RollinC.; Weaver, Benjamin A.; Wong, Daniel

    2007-05-02

    We present the results of applying new object classificationtechniques to difference images in the context of the Nearby SupernovaFactory supernova search. Most current supernova searches subtractreference images from new images, identify objects in these differenceimages, and apply simple threshold cuts on parameters such as statisticalsignificance, shape, and motionto reject objects such as cosmic rays,asteroids, and subtraction artifacts. Although most static objectssubtract cleanly, even a very low false positive detection rate can leadto hundreds of non-supernova candidates which must be vetted by humaninspection before triggering additional followup. In comparison to simplethreshold cuts, more sophisticated methods such as Boosted DecisionTrees, Random Forests, and Support Vector Machines provide dramaticallybetter object discrimination. At the Nearby Supernova Factory, we reducedthe number of non-supernova candidates by a factor of 10 while increasingour supernova identification efficiency. Methods such as these will becrucial for maintaining a reasonable false positive rate in the automatedtransient alert pipelines of upcoming projects such as PanSTARRS andLSST.

  3. Software Based Supernova Recognition

    Science.gov (United States)

    Walters, Stephen M.

    2014-05-01

    This paper describes software for detecting Supernova (SN) in images. The software can operate in real-time to discover SN while data is being collected so the instrumentation can immediately be re-tasked to perform spectroscopy or photometry of a discovery. Because the instrumentation captures two images per minute, the realtime budget is constrained to 30 seconds per target, a challenging goal. Using a set of two to four images, the program creates a "Reference" (REF) image and a "New" (NEW) image where all images are used in both NEW and REF but any SN survives the combination process only in the NEW image. This process produces good quality images having similar noise characteristics but without artifacts that might be interpreted as SN. The images are then adjusted for seeing and brightness differences using a variant of Tomaney and Crotts method of Point Spread Function (PSF) matching after which REF is subtracted from NEW to produce a Difference (DIF) image. A Classifier is then trained on a grid of artificial SN to estimate the statistical properties of four attributes and used in a process to mask false positives that can be clearly identified as such. Further training to avoid any remaining false positives sets the range, in standard deviations for each attribute, that the Classifier will accept as a valid SN. This training enables the Classifier to discriminate between SN and most subtraction residue. Lastly, the DIF image is scanned and measured by the Classifier to find locations where all four properties fall within their acceptance ranges. If multiple locations are found, the one best conforming to the training estimates is chosen. This location is then declared as a Candidate SN, the instrumentation re-tasked and the operator notified.

  4. Dust around Type Ia supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lifan

    2005-10-20

    An explanation is given of the low value of R lambda triple bond A lambda/E(B - V), the ratio of absolute to selective extinction deduced from Type Ia supernova observations. The idea involves scattering by dust clouds located in the circumstellar environment, or at the highest velocity shells of the supernova ejecta. The scattered light tends to reduce the effective R lambda in the optical, but has an opposite effect in the ultraviolet. The presence of circumstellar dust can be tested by ultraviolet to near infrared observations and by multi-epoch spectropolarimetry of SNe Ia.

  5. Magnetar-Powered Supernovae in Two Dimensions. I. Superluminous Supernovae

    CERN Document Server

    Chen, Ke-Jung; Sukhbold, Tuguldur

    2016-01-01

    Previous studies have shown that the radiation emitted by a rapidly rotating magnetar embedded in a young supernova can greatly amplify its luminosity. These one-dimensional studies have also revealed the existence of an instability arising from the piling up of radiatively accelerated matter in a thin dense shell deep inside the supernova. Here we examine the problem in two dimensions and find that, while instabilities cause mixing and fracture this shell into filamentary structures that reduce the density contrast, the concentration of matter in a hollow shell persists. The extent of the mixing depends upon the relative energy input by the magnetar and the kinetic energy of the inner ejecta. The light curve and spectrum of the resulting supernova will be appreciably altered, as will the appearance of the supernova remnant, which will be shellular and filamentary. A similar pile up and mixing might characterize other events where energy is input over an extended period by a centrally concentrated source, e.g...

  6. Distant Supernovae Indicate Ever-Expanding Universe

    Science.gov (United States)

    1998-12-01

    and its inhabitants are made comprise only a small fration of the gravitating mass in the Universe. There is now a new component, the "dark energy" which joins the "dark matter" in shaping the large-scale geometric and dynamical structure. Clearly, more observations are needed to further support the findings described here. They will soon be forthcoming, especially from new and large telescopes like the ESO Very Large Telescope (VLT) , that has recently delivered its first, impressive results. But already now, on the verge of the new millenium, we are having a first glimpse of extremely exciting and fundamental aspects in the continuing human quest for the deep truths of nature. Notes: [1] The ESO members of the "High-z Supernova Search" team (see URL: http://cfa-www.harvard.edu/cfa/oir/Research/supernova/HighZ.html) are Bruno Leibundgut and Patrick Woudt (ESO HQ, Garching, Germany) and Jason Spyromilio (Paranal Observatory, Chile). Chris Lidman (La Silla Observatory, Chile) and Isobel Hook (formerly ESO HQ, now Royal Observatory, Edinburgh, UK) are members of the "Supernova Cosmology Project" (see URL: http://www-supernova.lbl.gov/). The astronomers mostly used the ESO 3.6-m and 3.6-m NTT telescopes at La Silla for these research programmes. [2] In astronomy, the redshift (z) denotes the fraction by which the lines in the spectrum of an object are shifted towards longer wavelengths. The observed redshift of a distant galaxy or quasar gives a direct estimate of the universal expansion (i.e. the "recession velocity"). Since this expansion rate increases with the distance, the velocity is itself a function (the Hubble relation) of the distance to the object. For instance, a redshift of z = 0.1 corresponds to a velocity of 30,000 km/sec, and assuming a Hubble constant of 20 km/sec per million light-years, to a distance of about 1,500 million light-years. How to obtain ESO Press Information ESO Press Information is made available on the World-Wide Web (URL: http

  7. Theoretical and numerical analysis of coherent Smith-Purcell radiation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Coherent enhancement of Smith-Purcell radiation has attracted people's attention not only in adopting a better source but also in beam diagnostics aspect. In this paper, we study the intrinsic mechanism of coherent Smith-Purcell radiation on the basis of the van den Berg model. The emitted power of Smith-Purcell radiation is determined by the bunch profile in transverse and longitudinal directions. For short bunch whose longitudinal pulse length is comparable with the radiation wavelength, it can be concluded approximately that the power is proportional to the square number of electrons per bunch.

  8. Theobald Smith and animal parasitology: highlights on an anniversary.

    Science.gov (United States)

    Katz, F F

    1994-12-01

    In marking the 100th anniversary of the landmark publication in 1893 by Theobald Smith and Frederick L. Kilborne on cattle babesiosis and arthropod transmission, this article takes note of other contributions of Theobald Smith to the knowledge of a variety of parasitic organisms. Notable are his studies on the protozoan agent of avian enterohepatitis. The results of Smith's work in comparative pathology, to which he devoted his professional life, have had broad applications with economic and health benefits for domestic animals and humans.

  9. Are Supernovae Recorded in Indigenous Astronomical Traditions?

    CERN Document Server

    Hamacher, Duane W

    2014-01-01

    Novae and supernovae are rare astronomical events that would have had an influence on the sky-watching peoples who witnessed them. Although several bright novae/supernovae have been visible during recorded human history, there are many proposed but no confirmed accounts of supernovae in oral traditions or material culture. Criteria are established for confirming novae/supernovae in oral and material culture, and claims from around the world are discussed to determine if they meet these criteria. Australian Aboriginal traditions are explored for possible descriptions of novae/supernovae. Although representations of supernovae may exist in Indigenous traditions, and an account of a nova in Aboriginal traditions has been confirmed, there are currently no confirmed accounts of supernovae in Indigenous oral or material traditions.

  10. Supernova neutrinos and explosive nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Kajino, T. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan and Department of Astronomy, Graduate School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); Aoki, W. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Cheoun, M.-K. [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Hayakawa, T. [Japan Atomic Energy Agency, Shirakara-Shirane 2-4, Tokai-mura, Ibaraki 319-1195 (Japan); Hidaka, J.; Hirai, Y.; Shibagaki, S. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Mathews, G. J. [Center for Astrophysics, Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Nakamura, K. [Faculty of Science and Engineering, Waseda University, Ohkubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Suzuki, T. [Department of Physics, College of Humanities and Sciences, Nihon University, Sakurajosui 3-25-40, Setagaya-ku, Tokyo 156-8550 (Japan)

    2014-05-09

    Core-collapse supernovae eject huge amount of flux of energetic neutrinos. We studied the explosive nucleosyn-thesis in supernovae and found that several isotopes {sup 7}Li, {sup 11}B, {sup 92}Nb, {sup 138}La and {sup 180}Ta as well as r-process nuclei are affected by the neutrino interactions. The abundance of these isotopes therefore depends strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. We discuss first how to determine the neutrino temperatures in order to explain the observed solar system abundances of these isotopes, combined with Galactic chemical evolution of the light nuclei and the heavy r-process elements. We then study the effects of neutrino oscillation on their abundances, and propose a novel method to determine the still unknown neutrino oscillation parameters, mass hierarchy and θ{sub 13}, simultaneously. There is recent evidence that SiC X grains from the Murchison meteorite may contain supernova-produced light elements {sup 11}B and {sup 7}Li encapsulated in the presolar grains. Combining the recent experimental constraints on θ{sub 13}, we show that our method sug-gests at a marginal preference for an inverted neutrino mass hierarchy. Finally, we discuss supernova relic neutrinos that may indicate the softness of the equation of state (EoS) of nuclear matter as well as adiabatic conditions of the neutrino oscillation.

  11. Strange matter, detonations and supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Benvenuto, O.G.; Horvath, J.E.; Vucetich, H.

    1989-01-01

    The authors present a possible scenario driven by QCD deconfinement in a high density nuclear matter medium. Some expected consequences for type II supernovae explosions are also given, particularly, the output energy that might be enough to account for the observed events.

  12. ADAM SMITH: THE INVISIBLE HAND OR CONFIDENCE

    Directory of Open Access Journals (Sweden)

    Fernando Luis, Gache

    2010-01-01

    Full Text Available In 1776 Adam Smith raised the matter that an invisible hand was the one which moved the markets to obtain its efficiency. Despite in the present paper we are going to raise the hypothesis, that this invisible hand is in fact the confidence that each person feels when he is going to do business. That in addition it is unique, because it is different from the confidence of the others and that is a variable nonlinear that essentially is ligatured to respective personal histories. For that we are going to take as its bases the paper by Leopoldo Abadía (2009, with respect to the financial economy crisis that happened in 2007-2008, to evidence the form in which confidence operates. Therefore the contribution that we hope to do with this paper is to emphasize that, the level of confidence of the different actors, is the one which really moves the markets, (therefore the economy and that the crisis of the subprime mortgages is a confidence crisis at world-wide level.

  13. Dermatologic features of Smith-Magenis syndrome.

    Science.gov (United States)

    Guérin-Moreau, Morgane; Colin, Estelle; Nguyen, Sylvie; Andrieux, Joris; de Leersnyder, Hélène; Bonneau, Dominique; Martin, Ludovic

    2015-01-01

    Smith-Magenis syndrome (SMS) is characterized by distinctive facial and skeletal features, developmental delay, cognitive impairment, and behavioral abnormalities, including self-injurious behaviors. We aimed to investigate whether cutaneous features are common in SMS. We performed a complete skin examination in 20 young SMS patients. Skin features secondary to self-injurious behavior, such as bites, abrasions, dystrophic scars, limited spots of hyperkeratosis, anomalies of the nails, and whitlows, were found in the majority of patients. Acral pachydermia and fissured plantar keratoderma were common. Xerosis was constant and associated with extensive keratosis pilaris in the majority of patients. Dermatofibromas were frequent in older patients. The hair was dense and shiny, with an unusual hairline. Eyelash trichomegaly and heavy brows were common, as well as folliculitis on the back. The skin features of SMS have rarely been reported in the literature. Some of these are the consequence of neurobehavioral features, but some cutaneous features and abnormalities of appendages have not been reported in other related syndromes. Skin manifestations of SMS are varied, sometimes induced by self-injurious behavior and sometimes more specific. It remains to be determined whether the combination of the two kinds of signs could contribute to early diagnosis of the syndrome.

  14. Parcels and Land Ownership, Published in 2011, Smith County Government.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Parcels and Land Ownership dataset as of 2011. The extent of these data is generally Smith County, TN. This metadata was auto-generated through the Ramona GIS...

  15. Multiple self-healing squamous epithelioma of Ferguson-Smith

    DEFF Research Database (Denmark)

    Broesby-Olsen, Sigurd; Bygum, Anette; Gerdes, Anne-Marie;

    2008-01-01

    Multiple self-healing squamous epithelioma of Ferguson-Smith (MSSE) is a rare autosomal dominantly inherited disease, almost exclusively reported in patients of Scottish origin, with recurrent, histologically malignant tumours that undergo spontaneous regression. We report clinical observations...

  16. Neal Smith National Wildlife Refuge: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Neal Smith National Wildlife Refuge for the next 15 years. This plan outlines the...

  17. Neal Smith National Wildlife Refuge [Land Status Map

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Neal Smith National Wildlife Refuge. It was generated from rectified aerial photography,...

  18. Parcels and Land Ownership, Published in 2011, Smith County Government.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Parcels and Land Ownership dataset as of 2011. The extent of these data is generally Smith County, TX. This metadata was auto-generated through the Ramona GIS...

  19. Neal Smith National Wildlife Refuge : Fiscal Year 2003

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Neal Smith NWR outlines activities and accomplishments during the 2003 fiscal year. The report begins with an introduction to the...

  20. Llewellyn Smith, Director-General designate of CERN, discusses LHC

    CERN Multimedia

    Sweet, William N

    1992-01-01

    Christopher Llewellyn Smith was nominated by the Committee of Council to be Director General of CERN. He aims to pave the way for the Large Hadron Collider and utilize to the full the Large Electron-Positron machine.

  1. Neal Smith National Wildlife Refuge, Iowa Contaminants Investigation Final Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document serves as the final report for the Neal Smith National Wildlife Refuge (Refuge) (formerly known as the Walnut Creek National Wildlife Refuge)...

  2. David Simpson Receives 2012 Waldo E. Smith Medal: Citation

    Science.gov (United States)

    Lerner-Lam, Arthur

    2013-01-01

    David Simpson was awarded the 2012 Waldo E. Smith Medal at the AGU Fall Meeting Honors Ceremony, held on 5 December 2012 in San Francisco, Calif. The medal is for "extraordinary service to geophysics".

  3. Polydactyly in a boy with Smith-Magenis syndrome.

    Science.gov (United States)

    Mariannejensen, Lisbeth; Kirchhoff, Maria

    2005-10-01

    Smith-Magenis syndrome is a microdeletion syndrome involving chromosome 17p11.2. The characteristic features include mental retardation, dysmorphic facial features, minor skeletal anomalies including brachydactyly and behavioural abnormalities, such as disturbed sleep pattern, restlessness and self-destructive behaviour. We present a patient with this syndrome and with six digits on each hand. Polydactyly has not yet been described in Smith-Magenis syndrome as far as we know.

  4. Food resource partitioning of stingless bees; Trigona apicalis Smith, 1857, Trigana collina Smith, 1857 and Trigona fimbriata Smith, 1857 (Apidae, Meliponinae in a mixed deciduous forest

    Directory of Open Access Journals (Sweden)

    Jongjitvimol, T.

    2007-07-01

    Full Text Available Food resource partitioning of three species of stingless bees; Trigona apicalis Smith, 1857, T. collina Smith, 1857 and T. fimbriata Smith, 1857 at Phitsanulok Wildlife Conservation Devolopment and Extension Station were investigated from October 2003 to February 2005. The comparison study among T. apicalis, T. collina and T. fimbriata found different foraging times from food resources. Morphological study to examine the relationship between body size and foraging appendages among these species revealed significant differences in all characteristics (p<0.05. The results of food resource partitioning correlated with the competition theory. The three species appeared to avoid competition by performing a sign of coexistence in the same habitat possessing limited resources.

  5. 78 FR 23845 - Drawbridge Operation Regulations; Narrow Bay, Smith Point, NY

    Science.gov (United States)

    2013-04-23

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Narrow Bay, Smith Point, NY AGENCY... the Smith Point Bridge, mile 6.1, across Narrow Bay, between Smith Point and Fire Island, New York. The deviation is necessary to facilitate the Smith Point Triathlon. This deviation allows the...

  6. 78 FR 16286 - Neal Smith National Wildlife Refuge, Jasper County, IA; Final Comprehensive Conservation Plan and...

    Science.gov (United States)

    2013-03-14

    ... Fish and Wildlife Service Neal Smith National Wildlife Refuge, Jasper County, IA; Final Comprehensive... significant impact (FONSI) for the Environmental Assessment (EA) for Neal Smith National Wildlife Refuge... . Include ``Neal Smith Final CCP'' in the subject line of the message. U.S. Mail: Neal Smith...

  7. Andrew Smith: peame leidma tee majanduskasvuni, mis põhineb säästmisel, investeeringutel ja ekspordil / Andrew Smith

    Index Scriptorium Estoniae

    Smith, Andrew

    2010-01-01

    KPMG (UK) peaökonomist Andrew Smith vastab küsimustele, mis puudutavad majanduskriisi tekkimist, olukorra paranemist, majandusolukorda Suurbritannias, erinevusi Euroopa ja muude maailma piirkondade vahel, sarnasusi Eesti ja Suurbritannia majandusolukorra vahel ning prognoose edaspidiste arengute osas

  8. Andrew Smith: peame leidma tee majanduskasvuni, mis põhineb säästmisel, investeeringutel ja ekspordil / Andrew Smith

    Index Scriptorium Estoniae

    Smith, Andrew

    2010-01-01

    KPMG (UK) peaökonomist Andrew Smith vastab küsimustele, mis puudutavad majanduskriisi tekkimist, olukorra paranemist, majandusolukorda Suurbritannias, erinevusi Euroopa ja muude maailma piirkondade vahel, sarnasusi Eesti ja Suurbritannia majandusolukorra vahel ning prognoose edaspidiste arengute osas

  9. X-Ray Studies of Supernova Remnants: A Different View of Supernova Explosions

    CERN Document Server

    Badenes, Carles

    2010-01-01

    The unprecedented spatial and spectral resolutions of Chandra have revolutionized our view of the X-ray emission from supernova remnants. The excellent data sets accumulated on young, ejecta dominated objects like Cas A or Tycho present a unique opportunity to study at the same time the chemical and physical structure of the explosion debris and the characteristics of the circumstellar medium sculpted by the progenitor before the explosion. Supernova remnants can thus put strong constraints on fundamental aspects of both supernova explosion physics and stellar evolution scenarios for supernova progenitors. This view of the supernova phenomenon is completely independent of, and complementary to, the study of distant extragalactic supernovae at optical wavelengths. The calibration of these two techniques has recently become possible thanks to the detection and spectroscopic follow-up of supernova light echoes. In this paper, I will review the most relevant results on supernova remnants obtained during the first...

  10. The sloan digital sky survey-II supernova survey

    DEFF Research Database (Denmark)

    Frieman, Joshua A.; Bassett, Bruce; Becker, Andrew

    2008-01-01

    The Sloan Digital Sky Survey-II (SDSS-II) has embarked on a multi-year project to identify and measure light curves for intermediate-redshift (0.05 Ia supernovae (SNe Ia) using repeated five-band (ugriz) imaging over an area of 300 sq. deg. The survey region is a stripe 2.5° wide...... spectroscopically confirmed SNe Ia, 30 probable SNe Ia, 14 confirmed SNe Ib/c, 32 confirmed SNe II, plus a large number of photometrically identified SNe Ia, 94 of which have host-galaxy spectra taken so far. This paper provides an overview of the project and briefly describes the observations completed during...

  11. Type Ia Supernovae and the discovery of the Cosmic Acceleration

    CERN Document Server

    Clocchiatti, Alejandro

    2011-01-01

    I present a review of the research and analysis paths that converged to make Type Ia SNe the most mature cosmological distance estimator of the present time. The narrative starts with the first works in the early decades of the 20th century and finishes with the more recent results. The review was written by a member of the High Z Supernova Search Team, the international group of astronomers that discovered Cosmic Acceleration in 1998. This result, confirmed by the Supernova Cosmology Project in 1999, received an impressive string of recognition culminating with the current Nobel prize in Physics. The review is presented thinking of physicists with a strong interest in Cosmology, who might have pondered why was that, after decades of not being able to agree upon the rate of cosmic expansion, astronomers were so quick to concur on cosmic acceleration.

  12. Supernova neutrino detection in LAr TPCs

    Energy Technology Data Exchange (ETDEWEB)

    Gil-Botella, Ines, E-mail: ines.gil@ciemat.es [CIEMAT, Basic Research Department, Avenida Complutense, 22, 28040 Madrid (Spain)

    2011-08-10

    The neutrino burst from a core collapse supernova can provide information about the explosion mechanism and the mechanisms of proto neutron star cooling but also about the intrinsic properties of the neutrino such as flavor oscillations. One important question is to understand to which extent can the supernova and the neutrino physics be decoupled in the observation of a single supernova. The possibility to probe the neutrino mixing angle {theta}{sub 13} and the type of mass hierarchy from the detection of supernova neutrinos with liquid argon detectors is summarized in this paper. Moreover, a quantitative study about the possibility to constrain the supernova parameters is presented. A very massive liquid argon detector ({approx} 100 kton) is needed to perform accurate measurements of these parameters. In addition, these detectors could also provide information on the {nu}{sub e} component of the diffuse supernova neutrino background.

  13. Finding Distances to Type Ia Supernovae

    Science.gov (United States)

    Kohler, Susanna

    2016-03-01

    Type Ia supernovae are known as standard candles due to their consistency, allowing us to measure distances based on their brightness. But what if these explosions arent quite as consistent as we thought? Due scientific diligence requires careful checks, so a recent study investigates whether the metallicity of a supernovas environment affects the peak luminosity of the explosion.Metallicity Dependence?Type Ia supernovae are incredibly powerful tools for determining distances in our universe. Because these supernovae are formed by white dwarfs that explode when they reach a uniform accreted mass, the supernova peak luminosity is thought to be very consistent. This consistency allows these supernovae to be used as standard candles to measure distances to their host galaxies.But what if that peak luminosity is affected by a factor that we havent taken into account? Theorists have proposed that the luminosities of Type Ia supernovae might depend on the metallicity of their environments with high-metallicity environments suppressing supernova luminosities. If this is true, then we could be systematically mis-measuring cosmological distances using these supernovae.Testing AbundancesSupernova brightnesses vs. the metallicity of their environments. Low-metallicity supernovae (blue shading) and high-metallicity supernovae (red shading) have an average magnitude difference of ~0.14. [Adapted from Moreno-Raya et al. 2016]A team led by Manuel Moreno-Raya, of the Center for Energy, Environment and Technology (CIEMAT) in Spain, has observed 28 Type Ia supernovae in an effort to test for such a metallicity dependence. These supernovae each have independent distance measurements (e.g., from Cepheids or the Tully-Fisher relation).Moreno-Raya and collaborators used spectra from the 4.2-m William Herschel Telescope to estimate oxygen abundances in the region where each of these supernovae exploded. They then used these measurements to determine if metallicity of the local region

  14. VLBI observations of young Type II supernovae

    CERN Document Server

    Pérez-Torres, M A; Marcaide, J M

    2005-01-01

    We give an overview of circumstellar interaction in young Type II supernovae, as seen through the eyes of very-long-baseline interferometry (VLBI) observations. The resolution attained by such observations (best than 1 mas) is a powerful tool to probe the interaction that takes place after a supernova goes off. The direct imaging of a supernova permits, in principle, to estimate the deceleration of its expansion, and to obtain information on the eject and circumstellar density profiles, as well as estimates of the magnetic field intensity and relativistic particle energy density in the supernova. Unfortunately, only a handful of radio supernovae are close and bright enough as to permit their study with VLBI. We present results from our high-resolution observations of the nearby Type II radio supernovae SN1986J and SN2001gd.

  15. Improvements to type Ia supernova models

    Science.gov (United States)

    Saunders, Clare M.

    Type Ia Supernovae provided the first strong evidence of dark energy and are still an important tool for measuring the accelerated expansion of the universe. However, future improvements will be limited by systematic uncertainties in our use of Type Ia supernovae as standard candles. Using Type Ia supernovae for cosmology relies on our ability to standardize their absolute magnitudes, but this relies on imperfect models of supernova spectra time series. This thesis is focused on using data from the Nearby Supernova Factory both to understand current sources of uncertainty in standardizing Type Ia supernovae and to develop techniques that can be used to limit uncertainty in future analyses. (Abstract shortened by ProQuest.).

  16. Radio Supernovae in the Local Universe

    CERN Document Server

    Kamble, Atish; Berger, Edo; Zauderer, Ashley; Chakraborti, Sayan; Williams, Peter

    2014-01-01

    In the last three decades, about 50 radio supernovae have been detected as a result of targeted searches of optically discovered supernovae in the local universe. Despite this relatively small number some diversity among them has already been identified which is an indication of the underlying richness of radio supernovae waiting to be discovered. For example, comparison of star formation and supernova discovery rate imply that as many as half of the supernovae remain undetected in the traditional optical searches, either because of intrinsic dimness or due to dust obscuration. This has far reaching consequences to the models of stellar and galaxy evolution. A radio sky survey would be ideal to uncover larger supernova population. Transient radio sky would benefit significantly from such a survey. With the advent of advanced gravitational wave detectors a new window is set to open on the local Universe. Localization of these gravitational detectors is poor to identify electromagnetic counterparts of the gravi...

  17. The Scientific Potential of Supernova Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Pagliaroli, G.; Vissani, F.

    2013-04-15

    Thanks to recent theoretical progresses and to the test bench of SN1987A, it has been possible to improve our ability to extract information from the future observations. In this paper we discuss a parameterized model of the neutrino emission. Two applications of this model are considered: 1) the investigation of the scientific potential of a future supernova for the study of the astrophysical parameters; 2) the expectations regarding the diffuse supernova neutrino background, namely, the relic supernova neutrinos.

  18. Magnetares como fuentes para potenciar supernovas superluminosas

    Science.gov (United States)

    Bersten, M. C.; Benvenuto, O. G.

    2016-08-01

    Magnetars have been proposed as one of the possible sources to power the light curve of super-luminous supernovae. We have included the energy deposited by a hypothetical magnetar in our one-dimensional hydrodynamical code, and analyzed the dynamical effect on the supernova ejecta. In particular, we present a model for SN 2011kl, the first object associated with a ultra-long-duration gamma-ray burst. Finally, we show its effect on the light curves of hydrogen rich supernovae.

  19. Magnetar Powered Ordinary Type IIP Supernovae

    OpenAIRE

    Sukhbold, Tuguldur; Thompson, Todd A.

    2017-01-01

    We investigate the properties of Type IIP supernovae that are dominantly powered by the rotational kinetic energy of the newly born neutron star. While the spin-down of a magnetar has previously been proposed as a viable energy source in the context of super-luminous supernovae, we show that a similar mechanism could produce both normal and peculiar Type IIP supernova light curves from red supergiant progenitors for a range of initial spin periods and equivalent dipole magnetic field strength...

  20. Interface dynamos in supernova progenitors

    CERN Document Server

    Blackman, E G; Thomas, J H; Blackman, Eric G.; Nordhaus, Jason T.; Thomas, John H.

    2004-01-01

    Observational evidence for anisotropy in supernovae (SN) and their phenomenological connection to jetted sources such as gamma-ray bursts^Mhave revived considerations of the role magnetohydrodynamic outflows might play therein. Understanding the types of dynamos that might operate in supernova progenitors is therefore relevant. In contrast to previous work, here we study an ``interface dynamo'' for the conditions of a rapidly rotating neutron star surrounded by a convective envelope. Such dynamos have been studied for the Sun, naked white dwarfs,and post-AGB stars, where analogous configurations of strong shear layers surrounded by convective envelopes are present. The interface dynamo provides estimates of large-scale poloidal and toroidal fields, whose product enters the Poynting flux. Because the poloidal field is much weaker than the toroidal magnetic field, the actual average Poynting flux is lower than rough estimates which invoke the only the magnitude of the total magnetic energy. The lower value is s...

  1. Cosmology from Type Ia Supernovae

    CERN Document Server

    Perlmutter, S; Deustua, S; Fabbro, S; Goldhaber, Gerson; Groom, D E; Kim, A G; Kim, M Y; Knop, R A; Nugent, P; Pennypacker, C R; Goobar, A; Pain, R; Hook, I M; Lidman, C E; Ellis, Richard S; Irwin, M J; McMahon, R G; Ruiz-Lapuente, P; Walton, N A; Schaefer, B; Boyle, B J; Filippenko, A V; Matheson, T; Fruchter, A S; Panagia, N; Newberg, H J M; Couch, W J

    1997-01-01

    This presentation reports on first evidence for a low-mass-density/positive-cosmological-constant universe that will expand forever, based on observations of a set of 40 high-redshift supernovae. The experimental strategy, data sets, and analysis techniques are described. More extensive analyses of these results with some additional methods and data are presented in the more recent LBNL report #41801 (Perlmutter et al., 1998; accepted for publication in Ap.J.), astro-ph/9812133 . This Lawrence Berkeley National Laboratory reprint is a reduction of a poster presentation from the Cosmology Display Session #85 on 9 January 1998 at the American Astronomical Society meeting in Washington D.C. It is also available on the World Wide Web at http://supernova.LBL.gov/ This work has also been referenced in the literature by the pre-meeting abstract citation: Perlmutter et al., B.A.A.S., volume 29, page 1351 (1997).

  2. Environmental impact of Supernova Remnants

    CERN Document Server

    Dubner, Gloria

    2015-01-01

    The explosion of a supernovae (SN) represents the sudden injection of about 10^51 ergs of thermal and mechanical energy in a small region of space, causing the formation of powerful shock waves that propagate through the interstellar medium at speeds of several thousands of km/s. These waves sweep, compress and heat the interstellar material that they encounter, forming the supernova remnants. Their evolution over thousands of years change forever, irreversibly, not only the physical but also the chemical properties of a vast region of space that can span hundreds of parsecs. This contribution briefly analyzes the impact of these explosions, discussing the relevance of some phenomena usually associated with SNe and their remnants in the light of recent theoretical and observational results.

  3. Connecting supernovae with their environments

    Science.gov (United States)

    Galbany, L.

    2017-03-01

    We present MUSE observations of galaxy NGC 7469 from its Science Verification to show how powerful is the combination of high-resolution wide-field integral field spectroscopy with both photometric and spectroscopic observations of supernova (SN) explosions. Using STARLIGHT and H II explorer, we selected all H II regions of the galaxy and produced 2-dimensional maps of the Hα equivalent width, average luminosity-weighted stellar age, and oxygen abundance. We measured deprojected galactocentric distances for all H II regions, and radial gradients for all above-mentioned parameters. We positioned the type Ia SN2008ec in the Branch et al. diagram, and finally discussed the characteristics of the SN parent H II region compared to all other H II regions in the galaxy. In a near future, the AMUSING survey will be able to reproduce this analysis and construct statistical samples to enable the characterization of the progenitors of different supernova types.

  4. An Update on Radio Supernovae

    Science.gov (United States)

    van Dyk, Schuyler D.; Sramek, Richard A.; Weiler, Kurt W.; Montes, Marcos J.; Panagia, Nino

    The radio emission from supernovae (SNe) is nonthermal synchrotron radiation of high brightness temperature, with a ``turn-on'' delay at longer wavelengths, power-law decline after maximum with index beta, and spectral index alpha asymptotically decreasing with time to a final, optically thin value. Radio supernovae (RSNe) are best described by the Chevalier (1982) ``mini-shell'' model, with modifications by Weiler \\etal\\ (1990). RSNe observations provide a valuable probe of the SN circumstellar environment and constraints on progenitor masses. We present a progress report on a number of recent RSNe, as well as on new behavior from RSNe 1979C and 1980K, and on RSNe as potential distance indicators. In particular, we present updated radio light curves for SN 1993J in M81.

  5. Evidence for Nearby Supernova Explosions

    CERN Document Server

    Benítez, N; Canelles, M; Benitez, Narciso; Maiz-Apellaniz, Jesus; Canelles, Matilde

    2002-01-01

    Supernova explosions are one of the most energetic--and potentially lethal--phenomena in the Universe. Scientists have speculated for decades about the possible consequences for life on Earth of a nearby supernova, but plausible candidates for such an event were lacking. Here we show that the Scorpius-Centaurus OB association, a group of young stars currently located at~130 parsecs from the Sun, has generated 20 SN explosions during the last 11 Myr, some of them probably as close as 40 pc to our planet. We find that the deposition on Earth of 60Fe atoms produced by these explosions can explain the recent measurements of an excess of this isotope in deep ocean crust samples. We propose that ~2 Myr ago, one of the SNe exploded close enough to Earth to seriously damage the ozone layer, provoking or contributing to the Pliocene-Pleistocene boundary marine extinction.

  6. Convection in Type 2 supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D.S.

    1993-10-15

    Results are presented here from several two dimensional numerical calculations of events in Type II supernovae. A new 2-D hydrodynamics and neutrino transport code has been used to compute the effect on the supernova explosion mechanism of convection between the neutrinosphere and the shock. This convection is referred to as exterior convection to distinguish it from convection beneath the neutrinosphere. The model equations and initial and boundary conditions are presented along with the simulation results. The 2-D code was used to compute an exterior convective velocity to compare with the convective model of the Mayle and Wilson 1-D code. Results are presented from several runs with varying sizes of initial perturbation, as well as a case with no initial perturbation but including the effects of rotation. The M&W code does not produce an explosion using the 2-D convective velocity. Exterior convection enhances the outward propagation of the shock, but not enough to ensure a successful explosion. Analytic estimates of the growth rate of the neutron finger instability axe presented. It is shown that this instability can occur beneath the neutrinosphere of the proto-neutron star in a supernova explosion with a growth time of {approximately} 3 microseconds. The behavior of the high entropy bubble that forms between the shock and the neutrinosphere in one dimensional calculations of supernova is investigated. It has been speculated that this bubble is a site for {gamma}-process generation of heavy elements. Two dimensional calculations are presented of the time evolution of the hot bubble and the surrounding stellar material. Unlike one dimensional calculations, the 2D code fails to achieve high entropies in the bubble. When run in a spherically symmetric mode the 2-D code reaches entropies of {approximately} 200. When convection is allowed, the bubble reaches {approximately} 60 then the bubble begins to move upward into the cooler, denser material above it.

  7. Understanding Core-Collapse Supernovae

    CERN Document Server

    Burrows, A

    2004-01-01

    I summarize, in the form of an extended abstract, the ongoing efforts at the University of Arizona (and in collaboration) to understand core-collapse supernovae theoretically. Included are short discussions of 1D (SESAME) and 2D (VULCAN/2D) codes and results, as well as discussions of the possible role of rotation. Highlighted are recent developments in multi-dimensional radiation hydrodynamics and the essential physics of the neutrino-driven mechanism.

  8. Convection in Type 2 supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Douglas Scott [Univ. of California, Davis, CA (United States)

    1993-10-15

    Results are presented here from several two dimensional numerical calculations of events in Type II supernovae. A new 2-D hydrodynamics and neutrino transport code has been used to compute the effect on the supernova explosion mechanism of convection between the neutrinosphere and the shock. This convection is referred to as exterior convection to distinguish it from convection beneath the neutrinosphere. The model equations and initial and boundary conditions are presented along with the simulation results. The 2-D code was used to compute an exterior convective velocity to compare with the convective model of the Mayle and Wilson 1-D code. Results are presented from several runs with varying sizes of initial perturbation, as well as a case with no initial perturbation but including the effects of rotation. The M&W code does not produce an explosion using the 2-D convective velocity. Exterior convection enhances the outward propagation of the shock, but not enough to ensure a successful explosion. Analytic estimates of the growth rate of the neutron finger instability axe presented. It is shown that this instability can occur beneath the neutrinosphere of the proto-neutron star in a supernova explosion with a growth time of ~ 3 microseconds. The behavior of the high entropy bubble that forms between the shock and the neutrinosphere in one dimensional calculations of supernova is investigated. It has been speculated that this bubble is a site for γ-process generation of heavy elements. Two dimensional calculations are presented of the time evolution of the hot bubble and the surrounding stellar material. Unlike one dimensional calculations, the 2D code fails to achieve high entropies in the bubble. When run in a spherically symmetric mode the 2-D code reaches entropies of ~ 200. When convection is allowed, the bubble reaches ~60 then the bubble begins to move upward into the cooler, denser material above it.

  9. Cosmic Ray Acceleration in Supernova Remnants

    CERN Document Server

    Blasi, Pasquale

    2010-01-01

    We review the main observational and theoretical facts about acceleration of Galactic cosmic rays in supernova remnants, discussing the arguments in favor and against a connection between cosmic rays and supernova remnants, the so-called supernova remnant paradigm for the origin of Galactic cosmic rays. Recent developments in the modeling of the mechanism of diffusive shock acceleration are discussed, with emphasis on the role of 1) magnetic field amplification, 2) acceleration of nuclei heavier than hydrogen, 3) presence of neutrals in the circumstellar environment. The status of the supernova-cosmic ray connection in the time of Fermi-LAT and Cherenkov telescopes is also discussed.

  10. Pulsational-Pair Instability Supernovae

    CERN Document Server

    Woosley, S E

    2016-01-01

    The final evolution of stars in the mass range 60 - 150 solar masses is explored. Depending upon their mass loss and rotation rates, many of these stars will end their lives as pulsational pair-instability supernovae. Even a non-rotating 70 solar mass star is pulsationally unstable during oxygen shell burning and can power a sub-luminous supernova. Rotation decreases the limit further. For more massive stars, the pulsations are less frequent, span a longer time, and are more powerful. Violent pulsations eject not only any residual low density envelope, but also that fraction of the helium core mass outside about 35 - 50 solar masses. The remaining core of helium and heavy elements continues to evolve, ultimately forming an iron core of about 2.5 solar masses that probably collapses to a black hole. A variety of observational transients result with total durations ranging from days to 10,000 years, and luminosities from 10$^{41}$ to 10$^{44}$ erg s$^{-1}$. Many transients resemble ordinary Type IIp supernovae,...

  11. Dark Energy and Termonuclear Supernovae

    Science.gov (United States)

    Domíngez, I.; Bravo, E.; Piersanti, L.; Tornambé, A.; Straniero, O.; Höflich, P.

    2008-12-01

    Nowadays it is widely accepted that the current Universe is dominated by dark energy and exotic matter, the so called StandardModel of Cosmoloy or CDM model. All the available data (Thermonuclear Supernovae, Cosmic Microwave Background, Baryon Acoustic Oscillations, Large Scale Structure, etc.) are compatible with a flat Universe made by ~70% of dark energy. Up to now observations agree that dark energy may be the vacuum energy (or cosmological constant) although improvements are needed to constrain further its equation of state. In this context, the cosmic destiny of the Universe is no longer linked to its geometry but to the nature of dark energy; it may be flat and expand forever or collapse. To understand the nature of dark energy is probably the most fundamental problem in physics today; it may open new roads of knowledge and led to unify gravity with the other fundamental interactions in nature. It is expected that astronomical data will continue to provide directions to theorists and experimental physicists. Type Ia supernovae (SNe Ia) have played a fundamental role, showing the acceleration of the expansion rate of the Universe a decade ago, and up to now they are the only astronomical observations that provide a direct evidence of the acceleration. However, in order to determine the source of the dark energy term it is mandatory to improve the precision of supernovae as distance indicators on cosmological scale.

  12. OH Masers and Supernova Remnants

    CERN Document Server

    Wardle, Mark

    2012-01-01

    OH(1720 MHz) masers are created by the interaction of supernova remnants with molecular clouds. These masers are pumped by collisions in warm, shocked molecular gas with OH column densities in the range 10^{16}--10^{17} cm^{-2}. Excitation calculations suggest that inversion of the 6049 MHz OH line may occur at the higher column densities that have been inferred from main-line absorption studies of supernova remnants with the Green Bank Telescope. OH(6049 MHz) masers have therefore been proposed as a complementary indicator of remnant-cloud interaction. This motivated searches for 6049 MHz maser emission from supernova remnants using the Parkes 63 m and Effelsberg 100 m telescopes, and the Australia Telescope Compact Array. A total of forty-one remnants have been examined by one or more of these surveys, but without success. To check the accuracy of the OH column densities inferred from the single-dish observations we modelled OH absorption at 1667 MHz observed with the Very Large Array towards three supernov...

  13. A spitzer space telescope study of SN 2002hh: An infrared echo from a type llP supernova

    DEFF Research Database (Denmark)

    Meikle, W. P. S.; Mattila, S.; Gerardy, C. L.;

    2006-01-01

    Stars: Supernovae: General, supernovae: individual (NGC 6946), Stars: Supernovae: Individual: Alphanumeric: SN 2002hh Udgivelsesdato: May 22......Stars: Supernovae: General, supernovae: individual (NGC 6946), Stars: Supernovae: Individual: Alphanumeric: SN 2002hh Udgivelsesdato: May 22...

  14. 与孤独相溶的Patti Smith

    Institute of Scientific and Technical Information of China (English)

    Apollo

    1998-01-01

    孤独并非一种无奈,它更多的是一种心灵上安全的逃避。我记不清这是谁写给我信中的一句话了,但当我每次放 PattiSmith 的 CD时 ,都会想起它来。Patti Smith 也是孤独着的?我相信,我也自始至终都这样认为和评价 Patti Smith,从那张特立独行的《Horses》专辑起,我就没有想改变这种顽固的观点。纯粹意义上或者经典意义上的 Punk(朋克)艺术其顶峰期只有三四年的光景,从75年到78年间所诞生的这种不为较多人注目的 Punk 作品完全可以给 Punk 作完美的注释,当然绝不可能少了那张《Horses》,Patti Smith 最早也是最出色的作品,无论其艺术性还是商业性,它都取得了巨大成功。也便是从此起,Patti Smith 就开始孤独着

  15. Cygnus Loop Supernova Blast Wave

    Science.gov (United States)

    1993-01-01

    This is an image of a small portion of the Cygnus Loop supernova remnant, which marks the edge of a bubble-like, expanding blast wave from a colossal stellar explosion, occurring about 15,000 years ago. The HST image shows the structure behind the shock waves, allowing astronomers for the first time to directly compare the actual structure of the shock with theoretical model calculations. Besides supernova remnants, these shock models are important in understanding a wide range of astrophysical phenomena, from winds in newly-formed stars to cataclysmic stellar outbursts. The supernova blast is slamming into tenuous clouds of insterstellar gas. This collision heats and compresses the gas, causing it to glow. The shock thus acts as a searchlight revealing the structure of the interstellar medium. The detailed HST image shows the blast wave overrunning dense clumps of gas, which despite HST's high resolution, cannot be resolved. This means that the clumps of gas must be small enough to fit inside our solar system, making them relatively small structures by interstellar standards. A bluish ribbon of light stretching left to right across the picture might be a knot of gas ejected by the supernova; this interstellar 'bullet' traveling over three million miles per hour (5 million kilometres) is just catching up with the shock front, which has slowed down by ploughing into interstellar material. The Cygnus Loop appears as a faint ring of glowing gases about three degrees across (six times the diameter of the full Moon), located in the northern constellation, Cygnus the Swan. The supernova remnant is within the plane of our Milky Way galaxy and is 2,600 light-years away. The photo is a combination of separate images taken in three colors, oxygen atoms (blue) emit light at temperatures of 30,000 to 60,000 degrees Celsius (50,000 to 100,000 degrees Farenheit). Hydrogen atoms (green) arise throughout the region of shocked gas. Sulfur atoms (red) form when the gas cools to

  16. Methodological studies on the search for Gravitational Waves and Neutrinos from Type II Supernovae

    Science.gov (United States)

    Casentini, Claudio

    2016-02-01

    Type II SNe, also called Core-collapse SuperNovae have a neutrino (v) emission, as confirmed by SN 1987A, and are also potential sources of gravitational waves. Neutrinos and gravitational waves from these sources reach Earth almost contemporaneously and without relevant interaction with stellar matter and interstellar medium. The upcoming advanced gravitational interferometers would be sensitive enough to detect gravitational waves signals from close galactic Core-collapse SuperNovae events. Nevertheless, significant uncertainties on theoretical models of emission remain. A joint search of coincident low energy neutrinos and gravitational waves events from these sources would bring valuable information from the inner core of the collapsing star and would enhance the detection of the so-called Silent SuperNovae. Recently a project for a joint search involving gravitational wave interferometers and neutrino detectors has started. We discuss the benefits of a joint search and the status of the search project.

  17. The progenitors of supernovae Type Ia

    Science.gov (United States)

    Toonen, Silvia

    2014-09-01

    Despite the significance of Type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. SNeIa are generally thought to be thermonuclear explosions of carbon/oxygen (CO) white dwarfs (WDs). The canonical scenarios involve white dwarfs reaching the Chandrasekhar mass, either by accretion from a non-degenerate companion (single-degenerate channel, SD) or by a merger of two CO WDs (double-degenerate channel, DD). The study of SNeIa progenitors is a very active field of research for binary population synthesis (BPS) studies. The strength of the BPS approach is to study the effect of uncertainties in binary evolution on the macroscopic properties of a binary population, in order to constrain binary evolutionary processes. I will discuss the expected SNeIa rate from the BPS approach and the uncertainties in their progenitor evolution, and compare with current observations. I will also discuss the results of the POPCORN project in which four BPS codes were compared to better understand the differences in the predicted SNeIa rate of the SD channel. The goal of this project is to investigate whether differences in the simulated populations are due to numerical effects or whether they can be explained by differences in the input physics. I will show which assumptions in BPS codes affect the results most and hence should be studied in more detail.

  18. Adam Smith, Market and Social Change: Then and Now

    DEFF Research Database (Denmark)

    Bouchet, Dominique

    2017-01-01

    Adam Smith (1723-1790) provided us with a remarkable synthesis of the economic and political ideas of his time and developed a conceptual system to analyse social interactions that mattered for the wealth of nations. He proposed a radically different roadmap for the future development...... of the society he lived in. The fact that his original analyses were rooted in a given historical context and were founded on a well thought-through conceptual system should not be ignored. The galvanising effect of the dribs and drabs of Adam Smith ideas that have been bandied about are a long way from...... the powerful insights imbued in the original ideas. Putting those back into context, looking into how Smith proceeded then, trying to update his observations, might help us to be more attentive to the market changes and social challenges of our times....

  19. Characteristic Equation of the Modified Smith predictor to MIMO Systems

    Directory of Open Access Journals (Sweden)

    Jorge A. Herrera-Cuartas

    2013-11-01

    Full Text Available The delay in control systems is a feature frequently in real systems due to the transport of objects or information, a series connection of multiple systems or own processing and sensors delay, among others. Recently there have been several studies to identify the external delay MIMO systems, these works are focused on identification and on-line control of MIMO systems and use a multimodel structure based on modified Smith predictor using different search method. It is clear that for the implementation of the algorithm, and to obtain the convergence and stability analysis, it is necessary to have closed-loop equations of modified Smith predictor. However, in these works is not presented the analytical procedure, not be the main object, displaying only the closed loop equations without the procedure for obtaining it. Therefore, to respond, in this paper, we present an analytical way to derive the closed-loop equations of a modified Smith predictor.  

  20. [Historical aspects of the Smith-Lemli-Opitz syndrome].

    Science.gov (United States)

    Bzdúch, Vladimir; Behúlová, Darina; Skodová, Jozefína; Skokňová, Martina; Kozák, Libor

    2014-01-01

    The new malformation syndrome was first described approximately 50 years ago in three unrelated patients in Department of Pediatrics at the University of Wisconsin, Madison, (Smith, Lemli, Opitz 1964). This syndrome was called RSH syndrome after the first 3 patients studied. First Slovak patient with phenotypic features of this new syndrome was described by professor Sršeň in 1972. In 1994 Tint from VA Medical Center, E. Orange, New Jersey analyzed plasma sterols of patient with Smith-Lemli-Opitz syndrome and found out that in addition to low plasma cholesterol level, the patient had 1000-fold increase of the plasma level of 7-dehydrocholesterol, the immediate precursor of cholesterol biosynthesis. After this biochemical discovery Smith-Lemli-Opitz syndrome became the metabolic-malformation syndrome with an exactly defined impairment of cholesterol metabolism. The first patient with biochemically proved Smith-Lemli-Opitz syndrome in Slovakia was described by Behulova et al. (1997) in cooperation with Department of Biochemistry and Medical Biotechnology, Federico II University in Naples, Italy. The three years later a screening method UV spectrometry of serum lipids for detection of 7-dehydrocholesterol was established in Department of Biochemistry, University Children´s Hospital in cooperation with the Institute of preventive and clinical medicine in Bratislava (Skodova et al.,2000). First results of molecular analysis of the 7-dehydrocholesterol reductase gene in 10 unrelated Czech and Slovak patients with Smith-Lemli-Opitz syndrome were reported by Kozak et al. (2000). The same year the first prenatal diagnosis of Smith-Lemli-Opitz syndrome by mutation analysis was achieved (Bzduch et al., 2000). Our research activities on this topic drew good response from abroad.

  1. Bayesian Single-Epoch Photometric Classification of Supernovae

    CERN Document Server

    Poznanski, D; Gal-Yam, A; Poznanski, Dovi; Maoz, Dan; Gal-Yam, Avishay

    2006-01-01

    (abridged) Ongoing supernova (SN) surveys find hundreds of candidates, that require confirmation for their use. Traditional classification based on followup spectroscopy of all candidates is virtually impossible for these large samples. We present an automatic Bayesian classifying algorithm for supernovae, the SN-ABC. We rely solely on single-epoch multiband photometry and host-galaxy (photometric) redshift information to sort SN candidates into the two major types, Ia and core-collapse supernovae. We test the SN-ABC performance on published samples of SNe from the SNLS and GOODS projects that have both broad-band photometry and spectroscopic classification (so the true type is known). The SN-ABC correctly classifies up to 97% (85%) of the type Ia (II-P) SNe in SNLS, and similar fractions of the GOODS SNe, depending on photometric redshift quality. We further test our method on large artificial samples to explore possible biases, and find that, in deep surveys, SNe Ia are best classified at redshifts z >~ 0.6...

  2. Supernova remnants: the X-ray perspective

    NARCIS (Netherlands)

    Vink, J.

    2012-01-01

    Supernova remnants are beautiful astronomical objects that are also of high scientific interest, because they provide insights into supernova explosion mechanisms, and because they are the likely sources of Galactic cosmic rays. X-ray observations are an important means to study these objects. And i

  3. Single Degenerate Progenitors of Type Ia Supernovae

    Science.gov (United States)

    Bours, Madelon; Toonen, Silvia; Nelemans, Gijs

    2013-01-01

    There is a general agreement that Type Ia supernovae correspond to the thermonuclear runaway of a white dwarf (WD) in a compact binary. The details of these progenitor systems are still unclear. Using the population synthesis code SeBa and several assumption for the WD retention efficiency, we estimate the delay times and supernova rates for the single degenerate scenario.

  4. Supernova constraints on neutrino mass and mixing

    Indian Academy of Sciences (India)

    Srubabati Goswami

    2000-01-01

    In this article I review the constraints on neutrino mass and mixing coming from type-II supernovae. The bounds obtained on these parameters from shock reheating, -process nucleosynthesis and from SN1987A are discussed. Given the current constraints on neutrino mass and mixing the effect of oscillations of neutrinos from a nearby supernova explosion in future detectors will also be discussed.

  5. Cosmic-ray acceleration in supernova remnants

    NARCIS (Netherlands)

    Helder, E.A.

    2010-01-01

    Supernovae are among the most energetic events in the Universe. During the event, they expel their material with enormous speeds into the surroundings. In addition, supernovae are thought to transfer a sizable fraction of their energy into just a few particles: cosmic rays. These cosmic rays acquire

  6. Adam Smith et le “républicanisme”

    Directory of Open Access Journals (Sweden)

    Alexandra HYARD

    2003-10-01

    Full Text Available Je remercie Pierre Lurbe et Ann Thomson pour leurs remarques. Je tiens également à remercier Thierry Demals pour son aide précieuse. Néanmoins, je reste seule responsable des éventuelles erreurs contenues dans ce travail.Introduction Smith semble avoir toujours été en théorie un républicain, et il a sûrement eu le vrai esprit d’un républicain dans son amour de toute liberté rationnelle. (Rae 124 Par cette phrase, Rae nous livre son opinion sur une des questions relatives à Adam Smith (1723-1...

  7. Snapping Supernovae at z>1.7

    CERN Document Server

    Aldering, G; Kowalski, M; Linder, E V; Perlmutter, S; Aldering, Greg; Kim, Alex G.; Kowalski, Marek; Linder, Eric V.; Perlmutter, Saul

    2006-01-01

    We examine the utility of very high redshift Type Ia supernovae for cosmology and systematic uncertainty control. Next generation space surveys such as the Supernova/Acceleration Probe (SNAP) will obtain thousands of supernovae at z>1.7, beyond the design redshift for which the supernovae will be exquisitely characterized. We find that any z\\gtrsim2 standard candles' use for cosmological parameter estimation is quite modest and subject to pitfalls; we examine gravitational lensing, redshift calibration, and contamination effects in some detail. The very high redshift supernovae - both thermonuclear and core collapse - will provide copious interesting information on star formation, environment, and evolution. However, the new observational systematics that must be faced, as well as the limited expansion of SN-parameter space afforded, does not point to high value for 1.7

  8. Supernova shock breakout from a red supergiant.

    Science.gov (United States)

    Schawinski, Kevin; Justham, Stephen; Wolf, Christian; Podsiadlowski, Philipp; Sullivan, Mark; Steenbrugge, Katrien C; Bell, Tony; Röser, Hermann-Josef; Walker, Emma S; Astier, Pierre; Balam, Dave; Balland, Christophe; Carlberg, Ray; Conley, Alex; Fouchez, Dominique; Guy, Julien; Hardin, Delphine; Hook, Isobel; Howell, D Andrew; Pain, Reynald; Perrett, Kathy; Pritchet, Chris; Regnault, Nicolas; Yi, Sukyoung K

    2008-07-11

    Massive stars undergo a violent death when the supply of nuclear fuel in their cores is exhausted, resulting in a catastrophic "core-collapse" supernova. Such events are usually only detected at least a few days after the star has exploded. Observations of the supernova SNLS-04D2dc with the Galaxy Evolution Explorer space telescope reveal a radiative precursor from the supernova shock before the shock reached the surface of the star and show the initial expansion of the star at the beginning of the explosion. Theoretical models of the ultraviolet light curve confirm that the progenitor was a red supergiant, as expected for this type of supernova. These observations provide a way to probe the physics of core-collapse supernovae and the internal structures of their progenitor stars.

  9. Supernovae and Cosmology with Future European Facilities

    CERN Document Server

    Hook, I M

    2012-01-01

    Prospects for future supernova surveys are discussed, focusing on the ESA Euclid mission and the European Extremely Large Telescope(E-ELT), both expected to be in operation around the turn of the decade. Euclid is a 1.2m space survey telescope that will operate at visible and near-infrared wavelengths, and has the potential to find and obtain multi-band lightcurves for thousands of distant supernovae. The E-ELT is a planned general-purpose ground-based 40m-class optical-IR telescope with adaptive optics built in, which will be capable of obtaining spectra of Type Ia supernovae to redshifts of at least four. The contribution to supernova cosmology with these facilities will be discussed in the context of other future supernova programs such as those proposed for DES, JWST, LSST and WFIRST.

  10. The VLT Measures the Shape of a Type Ia Supernova

    Science.gov (United States)

    2003-08-01

    . " Measuring them requires an instrument that is very sensitive and very stable . " The VLT observation of SN 2001el in NGC 1448 ESO PR Photo 24a/03 ESO PR Photo 24a/03 [Preview - JPEG: 620 x 400 pix - 156k [Normal - JPEG: 1240 x 800 pix - 396k] ESO PR Photo 24b/03 ESO PR Photo 24b/03 [Preview - JPEG: 400 x 524 pix - 104k [Normal - JPEG: 800 x 1047 pix - 240k] Captions : PR Photo 24a/03 shows the spiral galaxy NGC 1448, as seen in an archive image from the Digital Sky Survey (Courtesy of STScI) and as seen close to the brightness maximum of the supernova using EMMI on the NTT. SN 2001el is marked by the arrow. The field measures 4.5 x 4.5 arcmin 2 ; North is up and east is right. PR Photo 24b/03 illustrates the optical spectrum of SN 2001el in NGC 1448 (upper panel). The middle and lower panels show the corresponding fractional polarisations. They measure the different numbers of photons oscillating in perpendicular directions; they are directly related to the geometry of the supernova. The shaded area indicates the spectral signatures of high-velocity matter in the expanding envelope. The measurement in faint and distant light sources of differences at a level of less than one percent is a considerable observational challenge. "However, the ESO Very Large Telescope (VLT) offers the precision, the light collecting power, as well as the specialized instrumentation required for such a demanding polarimetric observation" , explains Dietrich Baade . "But this project would not have been possible without the VLT being operated in service mode. It is indeed impossible to predict when a supernova will explode and we need to be ready all the time. Only service mode allows observations at short notice. Some years ago, it was a farsighted and courageous decision by ESO's directorate to put so much emphasis on Service Mode. And it was the team of competent and devoted ESO astronomers on Paranal who made this concept a practical success" , he adds. The astronomers [1] used the VLT multi

  11. Rapidly Rising Transients in the Supernova - Superluminous Supernova Gap

    CERN Document Server

    Arcavi, Iair; Howell, D Andrew; Bildsten, Lars; Leloudas, Giorgos; Hardin, Delphine; Prajs, Szymon; Perley, Daniel A; Svirski, Gilad; Gal-Yam, Avishay; Katz, Boaz; McCully, Curtis; Cenko, S Bradley; Lidman, Chris; Sullivan, Mark; Valenti, Stefano; Astier, Pierre; Balland, Cristophe; Carlberg, Ray G; Conley, Alex; Fouchez, Dominique; Guy, Julien; Pain, Reynald; Palanque-Delabrouille, Nathalie; Perrett, Kathy; Pritchet, Chris J; Regnault, Nicolas; Rich, James; Ruhlmann-Kleider, Vanina

    2015-01-01

    We present observations of four rapidly rising (t_{rise}~10d) transients with peak luminosities between those of supernovae (SNe) and superluminous SNe (M_{peak}~-20) - one discovered and followed by the Palomar Transient Factory (PTF) and three by the Supernova Legacy Survey (SNLS). The light curves resemble those of SN 2011kl, recently shown to be associated with an ultra-long-duration gamma ray burst (GRB), though no GRB was seen to accompany our SNe. The rapid rise to a luminous peak places these events in a unique part of SN phase space, challenging standard SN emission mechanisms. Spectra of the PTF event formally classify it as a Type II SN due to broad Halpha emission, but an unusual absorption feature, which can be interpreted as either high velocity Halpha (though deeper than in previously known cases) or Si II (as seen in Type Ia SNe), is also observed. We find that existing models of white dwarf detonations, CSM interaction, shock breakout in a wind (or steeper CSM) and magnetar spindown can not r...

  12. Statistics of Galactic Supernova Remnants

    Institute of Scientific and Technical Information of China (English)

    Jian-Wen Xu; Xi-Zhen Zhang; Jin-Lin Han

    2005-01-01

    We collected the basic parameters of 231 supernova remnants (SNRs) in our Galaxy, namely, distances (d) from the Sun, linear diameters (D), Galactic heights (Z), estimated ages (t), luminosities (L), surface brightness (∑) and flux densities (Si) at 1-GHz frequency and spectral indices (α). We tried to find possible correlations between these parameters. As expected, the linear diameters were found to increase with ages for the shell-type remnants, and also to have a tendency to increase with the Galactic heights. Both the surface brightness and luminosity of SNRs at 1-GHz tend to decrease with the linear diameter and with age. No other relations between the parameters were found.

  13. Petascale Supernova Simulation with CHIMERA

    Energy Technology Data Exchange (ETDEWEB)

    Messer, Bronson [ORNL; Bruenn, S. W. [Florida Atlantic University; Blondin, J. M. [North Carolina State University; Mezzacappa, Anthony [ORNL; Hix, William Raphael [ORNL; Dirk, Charlotte [Florida Atlantic University

    2007-01-01

    CHIMERA is a multi-dimensional radiation hydrodynamics code designed to study core-collapse supernovae. The code is made up of three essentially independent parts: a hydrodynamics module, a nuclear burning module, and a neutrino transport solver combined within an operator-split approach. We describe some ma jor algorithmic facets of the code and briefly discuss some recent results. The multi-physics nature of the problem, and the specific implementation of that physics in CHIMERA, provide a rather straightforward path to effective use of multi-core platforms in the near future.

  14. Petascale supernova simulation with CHIMERA

    Energy Technology Data Exchange (ETDEWEB)

    Messer, O E B [National Center for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6008 (United States); Bruenn, S W [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States); Blondin, J M [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States); Hix, W R [Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6354 (United States); Mezzacappa, A [Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6354 (United States); Dirk, C J [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States)

    2007-07-15

    CHIMERA is a multi-dimensional radiation hydrodynamics code designed to study core-collapse supernovae. The code is made up of three essentially independent parts: a hydrodynamics module, a nuclear burning module, and a neutrino transport solver combined within an operator-split approach. We describe some major algorithmic facets of the code and briefly discuss some recent results. The multi-physics nature of the problem, and the specific implementation of that physics in CHIMERA, provide a rather straightforward path to effective use of multi-core platforms in the near future.

  15. Shell-type Supernova Remnants

    OpenAIRE

    Völk, H.

    2006-01-01

    The role of Supernova Remnants (SNRs) for the production of the Galactic Cosmic Rays is reviewed from the point of view of theory and very high energy gamma-ray experiments. The point is made that theory can describe young SNRs very well, if the evidence from the synchrotron emission is used to empirically determine several parameters of the theory, and thus theory can predict the relative contributions of hadronic and leptonic gamma rays at TeV energies. This is exemplified for several objec...

  16. Final Technical Report: Discovering the Nature of Dark Energy: Towards Better Distances from Type Ia Supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Saurabh W. Jha

    2012-10-03

    The final technical report from the project "Discovering the Nature of Dark Energy: Towards Better Distances from Type Ia Supernovae" led at Rutgers the State University of New Jersey by Prof. Saurabh W. Jha is presented, including all publications resulting from this award.

  17. Progress on multi-waveband observations of supernova remnants

    OpenAIRE

    Yang, Xuejuan; Lu, Fangjun; Tian, Wenwu

    2008-01-01

    The development of observational techniques has inriched our knowledge of supernova remnants. In this paper, we review the main progresses in the last decade, including new discoveries of supernova remnants and the associated (rare type of) pulsars, nucleosynthesis, the interaction between supernova remnants and molecular clouds, dust in the supernova remnants, shock physics, and cosmic ray accelerations.

  18. Return to Baseline: Some Comments on Smith's Reinterpretation of Seclusionary Timeout.

    Science.gov (United States)

    Polsgrove, Lewis

    1982-01-01

    The author replies to an earlier contention of D. Smith (EC 133 830) that seclusionary timeout for behavior disordered children actually constitutes extinction rather than aversive control. The author cites methodological flaws in Smith's studies. (CL)

  19. Book Review: Inventing the Market: Smith, Hegel & Political Theory by Liza Herzog

    DEFF Research Database (Denmark)

    Boscan, Luis

    2014-01-01

    Review of: Inventing the Market: Smith, Hegel & Political Theory. Liza Herzog. Oxford University Press. April 2013.......Review of: Inventing the Market: Smith, Hegel & Political Theory. Liza Herzog. Oxford University Press. April 2013....

  20. Nähtamatu revolutsioon / David R. Smith ; interv. Philip Ball

    Index Scriptorium Estoniae

    Smith, David R.

    2007-01-01

    Tehisstruktuuriga metamaterjalid võivad põhjapanevalt muuta telekommunikatsiooni, andmekandjaid ja isegi päikeseenergeetikat, kinnitab Dukeѫi ülikooli töörühma juht David R. Smith. Artikkel üldpealkirja all: 10 tulevikutehnoloogiat 2007

  1. Smith Assists in Superstorm Sandy Relief Efforts | Poster

    Science.gov (United States)

    By Cathy McClintock, Guest Writer It should have been routine by now for a 30-year volunteer firefighter/ emergency medical technician from Thurmont, Md., but it wasn’t. That first night, as Ross Smith, IT security, looked across the Hudson River from Jersey City, N.J., he saw an unusually dark New York skyline.

  2. [Speech impairment and the Smith-Magenis syndrome].

    Science.gov (United States)

    Bergmann, C; Morlot, S; Ptok, M

    2007-08-01

    The Smith-Magenis syndrome (SMS) is a distinct multiple congenital anomaly caused by an interstitial deletion of the chromosome 17 p11.2. The phenotype includes dysmorphic features, mental retardation, speech delay, signs of peripheral neuropathy, and neurobehavioral problems. Also sensorineural and conduction hearing loss are described. In children with speech delay the physician should consider a genetic or syndromal disease.

  3. Smith-Magenis Syndrome: Genetic Basis and Clinical Implications

    Science.gov (United States)

    Finucane, Brenda; Haas-Givler, Barbara

    2009-01-01

    Smith-Magenis syndrome (SMS) is a neurobehavioral disorder associated with deletions and mutations of the "RAI1" gene on chromosome 17p11.2. Clinical features of the syndrome include intellectual disability, sleep disturbance, craniofacial differences, and a distinctive profile of stereotypic and self-injurious behaviors. Although the functional…

  4. Adam Smith and the Teaching of English Literature.

    Science.gov (United States)

    Court, Franklin E.

    1985-01-01

    Adam Smith used selections from English literature in his classroom during the eighteenth century because he believed that vernacular literature could provide a ready context for the teaching of ideological, social, and moral lessons. He believed that higher education should prepare students for the real business of the real world. (RM)

  5. Adam Smith and the Moral Economy of the Classroom System.

    Science.gov (United States)

    Hamilton, D.

    1980-01-01

    Traces the development of mass schooling to its origins in 19th-century Glasgow. Its importance as an intellectual and economic center enabled Glasgow to invent a solution to the problem of urban schooling, while the association of scholars like Adam Smith with Glasgow University made Scottish educational theories acceptable around the world. (DB)

  6. Genetics Home Reference: Smith-Lemli-Opitz syndrome

    Science.gov (United States)

    ... Smith-Lemli-Opitz syndrome: a multiple congenital anomaly/mental retardation syndrome due to an inborn error of cholesterol biosynthesis. Mol Genet Metab. 2000 Sep-Oct;71(1-2):163-74. Review. Citation on PubMed Sikora DM, Pettit-Kekel K, ...

  7. Phenotype and Natural History in Marshall-Smith Syndrome

    NARCIS (Netherlands)

    Shaw, Adam C.; van Balkom, Inge D. C.; Bauer, Mislen; Cole, Trevor R. P.; Delrue, Marie-Ange; Van Haeringen, Arie; Holmberg, Eva; Knight, Samantha J. L.; Mortier, Geert; Nampoothiri, Sheela; Puseljic, Silvija; Zenker, Martin; Cormier-Daire, Valerie; Hennekam, Raoul C. M.

    2010-01-01

    Marshall-Smith syndrome (MSS) is a distinctive entity of unknown etiology with fewer than 50 patients described in the medical literature to date. Through an International collaboration and use of an online wiki to facilitate data collection and sharing, we further delineate the phenotype and natura

  8. David E. Smith Receives 2012 Charles A. Whitten Medal: Citation

    Science.gov (United States)

    Phillips, Roger J.

    2013-01-01

    David E. Smith was awarded the 2012 Charles A. Whitten Medal at the AGU Fall Meeting Honors Ceremony, held on 5 December 2012 in San Francisco, Calif. The medal is for "outstanding achievement in research on the form and dynamics of the Earth and planets."

  9. Adam Smith and the Moral Economy of the Classroom System.

    Science.gov (United States)

    Hamilton, D.

    1980-01-01

    Traces the development of mass schooling to its origins in 19th-century Glasgow. Its importance as an intellectual and economic center enabled Glasgow to invent a solution to the problem of urban schooling, while the association of scholars like Adam Smith with Glasgow University made Scottish educational theories acceptable around the world. (DB)

  10. Adam Smith and the Teaching of English Literature.

    Science.gov (United States)

    Court, Franklin E.

    1985-01-01

    Adam Smith used selections from English literature in his classroom during the eighteenth century because he believed that vernacular literature could provide a ready context for the teaching of ideological, social, and moral lessons. He believed that higher education should prepare students for the real business of the real world. (RM)

  11. Pharmacological Cognitive Enhancers: Comment on Smith and Farah (2011)

    Science.gov (United States)

    Elliott, Glen R.; Elliott, Mark D.

    2011-01-01

    Smith and Farah (2011) provided a thought-provoking and perhaps deliberately provocative literature review of the use of stimulants to improve cognitive functioning in humans. They addressed the apparently increasing willingness of individuals mostly in the United States to use stimulants for this purpose and then summarized published literature…

  12. Nähtamatu revolutsioon / David R. Smith ; interv. Philip Ball

    Index Scriptorium Estoniae

    Smith, David R.

    2007-01-01

    Tehisstruktuuriga metamaterjalid võivad põhjapanevalt muuta telekommunikatsiooni, andmekandjaid ja isegi päikeseenergeetikat, kinnitab Dukeѫi ülikooli töörühma juht David R. Smith. Artikkel üldpealkirja all: 10 tulevikutehnoloogiat 2007

  13. An astrophysics data program investigation of spatial structure of supernova remnants

    Science.gov (United States)

    Hughes, John P.

    1993-01-01

    The final report on astrophysics data program investigation of spatial structure of supernova remnants for the period 1 Aug. 1989 to 31 Jul. 1991 is presented. The goal of the project was the study of the spatial structure of supernova remnants (SNR's) as observed in the x-ray band. A number of software tools were developed for the analysis: (1) a program to fit various geometric models to high resolution x-ray data, and (2) programs for Fourier Transform analysis of clumping in SNR's. These programs were applied to high resolution imager (HRI) data on the young galactic SNR's Tycho and Kepler with some success.

  14. Dark Matter Triggers of Supernovae

    CERN Document Server

    Graham, Peter W; Varela, Jaime

    2015-01-01

    The transit of primordial black holes through a white dwarf causes localized heating around the trajectory of the black hole through dynamical friction. For sufficiently massive black holes, this heat can initiate runaway thermonuclear fusion causing the white dwarf to explode as a supernova. The shape of the observed distribution of white dwarfs with masses up to $1.25 M_{\\odot}$ rules out primordial black holes with masses $\\sim 10^{19}$ gm - $10^{20}$ gm as a dominant constituent of the local dark matter density. Black holes with masses as large as $10^{24}$ gm will be excluded if recent observations by the NuStar collaboration of a population of white dwarfs near the galactic center are confirmed. Black holes in the mass range $10^{20}$ gm - $10^{22}$ gm are also constrained by the observed supernova rate, though these bounds are subject to astrophysical uncertainties. These bounds can be further strengthened through measurements of white dwarf binaries in gravitational wave observatories. The mechanism p...

  15. How supernovae launch galactic winds?

    Science.gov (United States)

    Fielding, Drummond; Quataert, Eliot; Martizzi, Davide; Faucher-Giguère, Claude-André

    2017-09-01

    We use idealized three-dimensional hydrodynamic simulations of global galactic discs to study the launching of galactic winds by supernovae (SNe). The simulations resolve the cooling radii of the majority of supernova remnants (SNRs) and thus self-consistently capture how SNe drive galactic winds. We find that SNe launch highly supersonic winds with properties that agree reasonably well with expectations from analytic models. The energy loading (η _E= \\dot{E}_wind/ \\dot{E}_SN) of the winds in our simulations are well converged with spatial resolution while the wind mass loading (η _M= \\dot{M}_wind/\\dot{M}_\\star) decreases with resolution at the resolutions we achieve. We present a simple analytic model based on the concept that SNRs with cooling radii greater than the local scaleheight break out of the disc and power the wind. This model successfully explains the dependence (or lack thereof) of ηE (and by extension ηM) on the gas surface density, star formation efficiency, disc radius and the clustering of SNe. The winds our simulations are weaker than expected in reality, likely due to the fact that we seed SNe preferentially at density peaks. Clustering SNe in time and space substantially increases the wind power.

  16. Type Ia Supernova Carbon Footprints

    CERN Document Server

    Thomas, R C; Aragon, C; Antilogus, P; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Childress, M; Chotard, N; Copin, Y; Fakhouri, H K; Gangler, E; Hsiao, E Y; Kerschhaggl, M; Kowalski, M; Loken, S; Nugent, P; Paech, K; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigault, M; Rubin, D; Runge, K; Scalzo, R; Smadja, G; Tao, C; Weaver, B A; Wu, C; Brown, P J; Milne, P A

    2011-01-01

    We present convincing evidence of unburned carbon at photospheric velocities in new observations of 5 Type Ia supernovae (SNe Ia) obtained by the Nearby Supernova Factory. These SNe are identified by examining 346 spectra from 124 SNe obtained before +2.5 d relative to maximum. Detections are based on the presence of relatively strong C II 6580 absorption "notches" in multiple spectra of each SN, aided by automated fitting with the SYNAPPS code. Four of the 5 SNe in question are otherwise spectroscopically unremarkable, with ions and ejection velocities typical of SNe Ia, but spectra of the fifth exhibits high-velocity (v > 20,000 km/s) Si II and Ca II features. On the other hand, the light curve properties are preferentially grouped, strongly suggesting a connection between carbon-positivity and broad band light curve/color behavior: Three of the 5 have relatively narrow light curves but also blue colors, and a fourth may be a dust-reddened member of this family. Accounting for signal-to-noise and phase, we ...

  17. Smith Newton Vehicle Performance Evaluation -- Gen 2 -- Cumulative; Energy Efficiency & Renewable Energy (EERE), Vehicle Technologies Office (VTO)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-10-01

    The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory is evaluating and documenting the performance of electric and plug-in hybrid electric drive systems in medium-duty trucks across the nation. U.S. companies participating in this evaluation project received funding from the American Recovery and Reinvestment Act to cover part of the cost of purchasing these vehicles. Through this project, Smith Electric Vehicles is building and deploying 500 all-electric medium-duty trucks that will be deployed by a variety of companies in diverse climates across the country.

  18. Discovery Prospects for a Biogenic Supernova Signature

    CERN Document Server

    Bishop, Shawn

    2010-01-01

    Within the universe, the astrophysical sites responsible for the production of radioactive 60Fe, of half life 2.62 Myr, are primarily confined to two: Type 1a supernovae and massive stars that end their lives as Type II supernovae. Approximately 2.8 Myr before the present, our planet was subjected to the debris of a supernova explosion. The terrestrial proxy for this event was the discovery of live atoms of 60Fe in a deep sea ferromanganese crust, from which the terrestrial flux of supernova 60Fe was deduced. The signature for this supernova event should also be contained in microfossils produced by magnetotactic bacteria extant at the time of the Earth-supernova interaction. Using estimates for the terrestrial supernova 60Fe flux, combined with our empirically derived microfossil concentrations of a deep sea drill core, we deduce a conservative estimate of the 60Fe fraction as 60Fe/Fe = 3.6 x 10^{-15}; this value sits comfortably within the sensitivity limit of present accelerator mass spectrometry capabilit...

  19. An Open Catalog for Supernova Data

    CERN Document Server

    Guillochon, James; Margutti, Raffaella

    2016-01-01

    We present the Open Supernova Catalog, an online collection of observations and metadata for presently 20,000+ supernovae and related candidates. The catalog is freely available on the web (https://sne.space), with its main interface having been designed to be a user-friendly, rapidly-searchable table accessible on desktop and mobile devices. In addition to the primary catalog table containing supernova metadata, an individual page is generated for each supernova which displays its available metadata, light curves, and spectra spanning X-ray to radio frequencies. The data presented in the catalog is automatically rebuilt on a daily basis and is constructed by parsing several dozen sources, including the data presented in the supernova literature and from secondary sources such as other web-based catalogs. Individual supernova data is stored in the hierarchical, human- and machine-readable JSON format, with the entirety of each supernova's data being contained within a single JSON file bearing its name. The se...

  20. Type Ia Supernova Modeling with Spectrophotometric Data from the Nearby Supernova Factory

    Science.gov (United States)

    Saunders, Clare; Nearby Supernova Factory

    2017-01-01

    Type Ia supernova cosmology is currently limited by dispersion in standardized magnitudes, driven by a combination of calibration uncertainty and so-called ‘intrinsic dispersion.' This intrinsic dispersion is caused by supernova behavior that the current lightcurve fitters do not account for, and it can involve systematic trends. Using data from the Nearby Supernova Factory, we have developed an empirical model that captures a wider range of Type Ia supernova behavior and can be used to improve standardized magnitude dispersion. To do this, Gaussian Processes and Expectation Maximization Factor Analysis are used to generate spectral time series templates that can be combined linearly. Variations of this model are optimized, alternatively for supernova standardization or for maximum accuracy in the description of supernova spectral features. We present these models along with interpretation of the model components. Methods are discussed for the most efficient application of the models in cosmological surveys.

  1. The Supernova Legacy Survey 3-year sample: Type Ia supernovae photometric distances and cosmological constraints

    Science.gov (United States)

    Guy, J.; Sullivan, M.; Conley, A.; Regnault, N.; Astier, P.; Balland, C.; Basa, S.; Carlberg, R. G.; Fouchez, D.; Hardin, D.; Hook, I. M.; Howell, D. A.; Pain, R.; Palanque-Delabrouille, N.; Perrett, K. M.; Pritchet, C. J.; Rich, J.; Ruhlmann-Kleider, V.; Balam, D.; Baumont, S.; Ellis, R. S.; Fabbro, S.; Fakhouri, H. K.; Fourmanoit, N.; González-Gaitán, S.; Graham, M. L.; Hsiao, E.; Kronborg, T.; Lidman, C.; Mourao, A. M.; Perlmutter, S.; Ripoche, P.; Suzuki, N.; Walker, E. S.

    2010-11-01

    Aims: We present photometric properties and distance measurements of 252 high redshift Type Ia supernovae (0.15 instrument at the Canada-France-Hawaii Telescope (CFHT), by repeatedly imaging four one-square degree fields in four bands. Follow-up spectroscopy was performed at the VLT, Gemini and Keck telescopes to confirm the nature of the supernovae and to measure their redshifts. Methods: Systematic uncertainties arising from light curve modeling are studied, making use of two techniques to derive the peak magnitude, shape and colour of the supernovae, and taking advantage of a precise calibration of the SNLS fields. Results: A flat ΛCDM cosmological fit to 231 SNLS high redshift type Ia supernovae alone gives Ω_M = 0.211 ± 0.034(stat) ± 0.069(sys). The dominant systematic uncertainty comes from uncertainties in the photometric calibration. Systematic uncertainties from light curve fitters come next with a total contribution of ±0.026 on Ω_M. No clear evidence is found for a possible evolution of the slope (β) of the colour-luminosity relation with redshift. Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. Based on observations obtained at the European Southern Observatory using the Very Large Telescope on the Cerro Paranal (ESO Large Programme 171.A-0486 & 176.A-0589). Based on observations (programs GS-2003B-Q-8, GN-2003B-Q-9, GS-2004A-Q-11, GN-2004A-Q-19, GS-2004B-Q-31, GN-2004B-Q-16, GS-2005A-Q-11, GN-2005A-Q-11, GS-2005B-Q-6, GN-2005B-Q-7, GN-2006A-Q-7, GN-2006B

  2. An Open Catalog for Supernova Data

    Science.gov (United States)

    Guillochon, James; Parrent, Jerod; Kelley, Luke Zoltan; Margutti, Raffaella

    2017-01-01

    We present the Open Supernova Catalog, an online collection of observations and metadata for presently 36,000+ supernovae and related candidates. The catalog is freely available on the web (https://sne.space), with its main interface having been designed to be a user-friendly, rapidly searchable table accessible on desktop and mobile devices. In addition to the primary catalog table containing supernova metadata, an individual page is generated for each supernova, which displays its available metadata, light curves, and spectra spanning X-ray to radio frequencies. The data presented in the catalog is automatically rebuilt on a daily basis and is constructed by parsing several dozen sources, including the data presented in the supernova literature and from secondary sources such as other web-based catalogs. Individual supernova data is stored in the hierarchical, human- and machine-readable JSON format, with the entirety of each supernova’s data being contained within a single JSON file bearing its name. The setup we present here, which is based on open-source software maintained via git repositories hosted on github, enables anyone to download the entirety of the supernova data set to their home computer in minutes, and to make contributions of their own data back to the catalog via git. As the supernova data set continues to grow, especially in the upcoming era of all-sky synoptic telescopes, which will increase the total number of events by orders of magnitude, we hope that the catalog we have designed will be a valuable tool for the community to analyze both historical and contemporary supernovae.

  3. A Cabinet of Mathematical Curiosities at Teachers College: David Eugene Smith's Collection

    Science.gov (United States)

    Murray, Diane R.

    2012-01-01

    This dissertation is a history of David Eugene Smith's collection of historical books, manuscripts, portraits, and instruments related to mathematics. The study analyzes surviving documents, images, objects, college announcements and catalogs, and secondary sources related to Smith's collection. David Eugene Smith (1860-1944) travelled…

  4. 77 FR 2317 - Captain John Smith Chesapeake National Historic Trail Advisory Council

    Science.gov (United States)

    2012-01-17

    ... National Park Service Captain John Smith Chesapeake National Historic Trail Advisory Council AGENCY... Captain John Smith Chesapeake National Historic Trail will hold a meeting via conference call. Designated... voyages of Captain John Smith to chart the land and waterways of the Chesapeake Bay. This meeting...

  5. 77 FR 50155 - Neal Smith National Wildlife Refuge, Jasper County, IA

    Science.gov (United States)

    2012-08-20

    ... Fish and Wildlife Service Neal Smith National Wildlife Refuge, Jasper County, IA AGENCY: Fish and... plan (CCP) and environmental assessment (EA) for Neal Smith National Wildlife Refuge (Refuge, NWR) for...: r3planning@fws.gov . Include ``Neal Smith Draft CCP/ EA'' in the subject line of the message. Fax:...

  6. 78 FR 32250 - CDM Smith and Dynamac Corp; Transfer of Data

    Science.gov (United States)

    2013-05-29

    ... AGENCY CDM Smith and Dynamac Corp; Transfer of Data AGENCY: Environmental Protection Agency (EPA). ACTION... Confidential Business Information (CBI) by the submitter, will be transferred to CDM Smith and its subcontractor, Dynamac Corp, in accordance with 40 CFR 2.307(h)(3) and 2.308(i)(2). CDM Smith and...

  7. 78 FR 2295 - Charlissa C. Smith; Establishment of Atomic Safety and Licensing Board

    Science.gov (United States)

    2013-01-10

    ... COMMISSION Charlissa C. Smith; Establishment of Atomic Safety and Licensing Board Pursuant to delegation by.... Smith, (Denial of Senior Reactor Operator License). This proceeding concerns a hearing request from Charlissa C. Smith, dated December 5, 2012, challenging a denial letter from the Office of Nuclear...

  8. HISTORIA ECONÓMICA: El padre de la economia:Adam Smith

    OpenAIRE

    Accensi Martínez, Maria Cinta

    2016-01-01

    Peer-reviewed Artículo que describe una pequeña bibliografía del padre de la economía Adam Smith Article que descriu una petita bibliografia sobre el pare de l'economia Adam Smith. This article include a brief bibliography about Adam Smith.

  9. Postexplosion hydrodynamics of supernovae in red supergiants

    Science.gov (United States)

    Herant, Marc; Woosley, S. E.

    1994-01-01

    Shock propagation, mixing, and clumping are studied in the explosion of red supergiants as Type II supernovae using a two-dimensional smooth particle hydrodynamic (SPH) code. We show that extensive Rayleigh-Talor instabilities develop in the ejecta in the wake of the reverse shock wave. In all cases, the shell structure of the progenitor is obliterated to leave a clumpy, well-mixed supernova remnant. However, the occurrence of mass loss during the lifetime of the progenitor can significantly reduce the amount of mixing. These results are independent of the Type II supernova explosion mechanism.

  10. Chiral transport of neutrinos in supernovae

    Directory of Open Access Journals (Sweden)

    Yamamoto Naoki

    2017-01-01

    Full Text Available The conventional neutrino transport theory for core-collapse supernovae misses one key property of neutrinos: the left-handedness. The chirality of neutrinos modifies the hydrodynamic behavior at the macroscopic scale and leads to topological transport phenomena. We argue that such transport phenomena should play important roles in the evolution of core-collapse supernovae, and, in particular, lead to a tendency toward the inverse energy cascade from small to larger scales, which may be relevant to the origin of the supernova explosion.

  11. Object Classification at the Nearby Supernova Factory

    Energy Technology Data Exchange (ETDEWEB)

    Aragon, Cecilia R.; Bailey, Stephen; Aragon, Cecilia R.; Romano, Raquel; Thomas, Rollin C.; Weaver, B. A.; Wong, D.

    2007-12-21

    We present the results of applying new object classification techniques to the supernova search of the Nearby Supernova Factory. In comparison to simple threshold cuts, more sophisticated methods such as boosted decision trees, random forests, and support vector machines provide dramatically better object discrimination: we reduced the number of nonsupernova candidates by a factor of 10 while increasing our supernova identification efficiency. Methods such as these will be crucial for maintaining a reasonable false positive rate in the automated transient alert pipelines of upcoming large optical surveys.

  12. Chiral transport of neutrinos in supernovae

    CERN Document Server

    Yamamoto, Naoki

    2016-01-01

    The conventional neutrino transport theory for core-collapse supernovae misses one key property of neutrinos: the left-handedness. The chirality of neutrinos modifies the hydrodynamic behavior at the macroscopic scale and leads to topological transport phenomena. We argue that such transport phenomena should play important roles in the evolution of core-collapse supernovae, and, in particular, lead to a tendency toward the inverse energy cascade from small to larger scales, which may be relevant to the origin of the supernova explosion.

  13. A New Supernova Discovery/Classification

    Science.gov (United States)

    Howell, D. A.; Nugent, P. E.; Sullivan, M.; Gal-Yam, A.

    2010-10-01

    The Type Ia supernova science working group of the Palomar Transient Factory (ATEL#1964) reports the discovery of the Type Ia supernova PTF10ygu at RA=09:37:30.30, Dec=+23:09:33.6 (J2000) in the host galaxy NGC 2929 at z=0.025. The supernova was discovered on Oct. 12.5 UT when it was at magnitude 19.2 in R-band (calibrated wrt the USNO catalog). There was nothing at this location on Oct 8.5 UT to a limiting magnitude of 20.3, and a marginal detection (S/N=5) at R=19.6 on Oct.

  14. Supernovae and Gamma-Ray Bursts

    Science.gov (United States)

    Livio, Mario; Panagia, Nino; Sahu, Kailash

    2001-07-01

    Participants; Preface; Gamma-ray burst-supernova relation B. Paczynski; Observations of gamma-ray bursts G. Fishman; Fireballs T. Piran; Gamma-ray mechanisms M. Rees; Prompt optical emission from gamma-ray bursts R. Kehoe, C. Akerlof, R. Balsano, S. Barthelmy, J. Bloch, P. Butterworth, D. Casperson, T. Cline, S. Fletcher, F. Frontera, G. Gisler, J. Heise, J. Hills, K. Hurley, B. Lee, S. Marshall, T. McKay, A. Pawl, L. Piro, B. Priedhorsky, J. Szymanski and J. Wren; X-ray afterglows of gamma-ray bursts L. Piro; The first year of optical-IR observations of SN1998bw I. Danziger, T. Augusteijn, J. Brewer, E. Cappellaro, V. Doublier, T. Galama, J. Gonzalez, O. Hainaut, B. Leibundgut, C. Lidman, P. Mazzali, K. Nomoto, F. Patat, J. Spyromilio, M. Turatto, J. Van Paradijs, P. Vreeswijk and J. Walsh; X-ray emission of Supernova 1998bw in the error box of GRB980425 E. Pian; Direct analysis of spectra of type Ic supernovae D. Branch; The interaction of supernovae and gamma-ray bursts with their surroundings R. Chevalier; Magnetars, soft gamma-ray repeaters and gamma-ray bursts A. Harding; Super-luminous supernova remnants Y. -H. Chu, C. -H. Chen and S. -P. Lai; The properties of hypernovae: SNe Ic 1998bw, 1997ef, and SN IIn 1997cy K. Nomoto, P. Mazzali, T. Nakamura, K. Iwanmoto, K. Maeda, T. Suzuki, M. Turatto, I. Danziger and F. Patat; Collapsars, Gamma-Ray Bursts, and Supernovae S. Woosley, A. MacFadyen and A. Heger; Pre-supernova evolution of massive stars N. Panagia and G. Bono; Radio supernovae and GRB 980425 K. Weiler, N. Panagia, R. Sramek, S. Van Dyk, M. Montes and C. Lacey; Models for Ia supernovae and evolutionary effects P. Hoflich and I. Dominguez; Deflagration to detonation A. Khokhlov; Universality in SN Iae and the Phillips relation D. Arnett; Abundances from supernovae F. -K. Thielemann, F. Brachwitz, C. Freiburghaus, S. Rosswog, K. Iwamoto, T. Nakamura, K. Nomoto, H. Umeda, K. Langanke, G. Martinez-Pinedo, D. Dean, W. Hix and M. Strayer; Sne, GRBs, and the

  15. A Comprehensive Investigation Into Modeling Supernovae Spectra

    Science.gov (United States)

    Hillier, Desmond

    Supernovae are a rich source of information. By studying their light curves and spectra we gain insights into stellar evolution, the nature of the progenitor star, surface abundances at the time of the explosion, whether previous mass-loss episodes have occurred, the physics of the explosion including the amount and type of elements synthesized, and whether the explosion has produced significant mixing between shells of different chemical composition. To maximize the information that can be gleaned from observations of supernovae it is essential that we have the necessary spectroscopic tools. To this end, we are developing a code, CMFGEN, capable of modeling supernova light curves and spectra. The code is currently being used, to study core-collapse supernovae as well as those arising from the nuclear detonation of a White Dwarf star. We wish to extend CMFGEN's capabilities by developing a procedure to handle non-monotonic velocity flows so that we can treat shock breakout and the interaction of supernova ejecta with circumstellar material. We will also investigate magnetar-powered SNe, and explore the connection between Type Ib and Type Ic supernovae and those supernovae associated with long-duration gamma-ray bursters. Through detailed studies of individual supernova, and through the construction of model grids, we are able to infer deficiencies in our modeling, in our atomic data, and in the progenitor models, and hence make refinements so that we can improve our understanding of all SNe classes. Previous (IUE), current (HST, Chandra, GALEX), and future NASA missions (James Webb Telescope) do/will provide a wealth of data on supernovae. The proposed research is related to strategic subgoal 3D: "Discover the origin, structure, evolution, and destiny of the universe, and search for Earth-like planets." Supernovae are inherently coupled to the evolution of the universe and life: They can trigger star formation and they provide the raw materials (e.g., oxygen

  16. Neutrino scattering and flavor transformation in supernovae

    CERN Document Server

    Cherry, John F; Friedland, Alexander; Fuller, George M; Vlasenko, Alexey

    2012-01-01

    We argue that the small fraction of neutrinos that undergo direction-changing scattering outside of the neutrinosphere could have significant influence on neutrino flavor transformation in core-collapse supernova environments. We show that the standard treatment for collective neutrino flavor transformation is adequate at late times, but could be inadequate in the crucial shock revival/explosion epoch of core-collapse supernovae, where the potentials that govern neutrino flavor evolution are affected by the scattered neutrinos. Taking account of this effect, and the way it couples to entropy and composition, will require a new paradigm in supernova modeling.

  17. Observational data on Galactic supernova remnants: II. The supernova remnants within l = 90°-270°

    Directory of Open Access Journals (Sweden)

    Guseinov O.H.

    2004-01-01

    Full Text Available We have collected all the available data on Galactic supernova remnants given in the literature. The data of Galactic supernova remnants located in the Galactic longitude interval l=90° - 270° in all spectral bands are represented in this work. We have adopted distance values for the SNRs by examining these data. The data of various types on neutron stars connected to these supernova remnants are also represented. Remarks of some authors and by ourselves regarding the data and some properties of both the supernova remnants and the point sources are given.

  18. X-ray studies of supernova remnants: a different view of supernova explosions.

    Science.gov (United States)

    Badenes, Carles

    2010-04-20

    The unprecedented spatial and spectral resolutions of Chandra have revolutionized our view of the X-ray emission from supernova remnants. The excellent datasets accumulated on young, ejecta-dominated objects like Cas A or Tycho present a unique opportunity to study at the same time the chemical and physical structure of the explosion debris and the characteristics of the circumstellar medium sculpted by the progenitor before the explosion. Supernova remnants can thus put strong constraints on fundamental aspects of both supernova explosion physics and stellar evolution scenarios for supernova progenitors. This view of the supernova phenomenon is completely independent of, and complementary to, the study of distant extragalactic supernovae at optical wavelengths. The calibration of these two techniques has recently become possible thanks to the detection and spectroscopic follow-up of supernova light echoes. In this paper, I review the most relevant results on supernova remnants obtained during the first decade of Chandra and the impact that these results have had on open issues in supernova research.

  19. Constraining Cosmic Evolution of Type Ia Supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Ryan J.; Filippenko, Alexei V.; Aguilera, C.; Becker, A.C.; Blondin, S.; Challis, P.; Clocchiatti, A.; Covarrubias, R.; Davis, T.M.; Garnavich, P.M.; Jha, S.; Kirshner, R.P.; Krisciunas, K.; Leibundgut, B.; Li, W.; Matheson, T.; Miceli, A.; Miknaitis, G.; Pignata, G.; Rest, A.; Riess, A.G.; /UC, Berkeley, Astron. Dept. /Cerro-Tololo InterAmerican Obs. /Washington U., Seattle, Astron. Dept. /Harvard-Smithsonian Ctr. Astrophys. /Chile U., Catolica /Bohr Inst. /Notre Dame U. /KIPAC, Menlo Park /Texas A-M /European Southern Observ. /NOAO, Tucson /Fermilab /Chile U., Santiago /Harvard U., Phys. Dept. /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Res. Sch. Astron. Astrophys., Weston Creek /Stockholm U. /Hawaii U. /Illinois U., Urbana, Astron. Dept.

    2008-02-13

    We present the first large-scale effort of creating composite spectra of high-redshift type Ia supernovae (SNe Ia) and comparing them to low-redshift counterparts. Through the ESSENCE project, we have obtained 107 spectra of 88 high-redshift SNe Ia with excellent light-curve information. In addition, we have obtained 397 spectra of low-redshift SNe through a multiple-decade effort at Lick and Keck Observatories, and we have used 45 ultraviolet spectra obtained by HST/IUE. The low-redshift spectra act as a control sample when comparing to the ESSENCE spectra. In all instances, the ESSENCE and Lick composite spectra appear very similar. The addition of galaxy light to the Lick composite spectra allows a nearly perfect match of the overall spectral-energy distribution with the ESSENCE composite spectra, indicating that the high-redshift SNe are more contaminated with host-galaxy light than their low-redshift counterparts. This is caused by observing objects at all redshifts with similar slit widths, which corresponds to different projected distances. After correcting for the galaxy-light contamination, subtle differences in the spectra remain. We have estimated the systematic errors when using current spectral templates for K-corrections to be {approx}0.02 mag. The variance in the composite spectra give an estimate of the intrinsic variance in low-redshift maximum-light SN spectra of {approx}3% in the optical and growing toward the ultraviolet. The difference between the maximum-light low and high-redshift spectra constrain SN evolution between our samples to be < 10% in the rest-frame optical.

  20. Radio emision from supernova remnants

    Science.gov (United States)

    Dubner, G.

    2016-06-01

    The vast majority of supernova remnants (SNRs) in our Galaxy and nearby galaxies have been discovered through radio observations, and only a very small number of the SNRs catalogued in the Milky Way have not been detected in the radio band, or are poorly defined by current radio observations. The study of the radio emission from SNRs is an excellent tool to investigate morphological characteristics, marking the location of shock fronts and contact discontinuities; the presence, orientation and intensity of the magnetic field; the energy spectrum of the emitting particles; and the dynamical consequences of the interaction with the circumstellar and interstellar medium. I will review the present knowledge of different important aspects of radio remnants and their impact on the interstellar gas. Also, new radio studies of the Crab Nebula carried out with the Karl Jansky Very Large Array (JVLA) at 3 GHz and with ALMA at 100 GHz, will be presented.

  1. Supernova 1987A at 30

    Science.gov (United States)

    Spyromilio, J.; Leibundgut, B.; Fransson, C.; Larsson, J.; Migotto, K.; Girard, J.

    2017-03-01

    Thirty years on, SN 1987A continues to develop and, over the last decade in particular, has: revealed the presence of a large centrally concentrated reservoir of dust; shown the presence of molecular species within the ejecta; expanded such that the ejecta structure is angularly resolved; begun the destruction of the circumstellar ring and transitioned to being dominated by energy sources external to the ejecta. We are participating in a live experiment in the creation of a supernova remnant and here the recent progress is briefly overviewed. Exciting developments can be expected as the ejecta and the reverse shock continue their interaction, the X-rays penetrate into the cold molecular core and we observe the return of the material into the interstellar medium. We anticipate that the nature of the remnant of the leptonisation event in the centre will also be revealed.

  2. Progenitors of Supernovae Type Ia

    CERN Document Server

    Toonen, S; Bours, M; Zwart, S Portegies; Claeys, J; Mennekens, N; Ruiter, A

    2013-01-01

    Despite the significance of Type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. The standard scenarios involve thermonuclear explosions of carbon/oxygen white dwarfs approaching the Chandrasekhar mass; either by accretion from a companion or by a merger of two white dwarfs. We investigate the contribution from both channels to the SNIa rate with the binary population synthesis (BPS) code SeBa in order to constrain binary processes such as the mass retention efficiency of WD accretion and common envelope evolution. We determine the theoretical rates and delay time distribution of SNIa progenitors and in particular study how assumptions affect the predicted rates.

  3. ANTIPROTONS PRODUCED IN SUPERNOVA REMNANTS

    Energy Technology Data Exchange (ETDEWEB)

    Berezhko, E. G.; Ksenofontov, L. T., E-mail: ksenofon@ikfia.sbras.ru [Yu. G. Shafer Institute of Cosmophysical Research and Aeronomy, 31 Lenin Avenue, 677891 Yakutsk (Russian Federation)

    2014-08-20

    We present the energy spectrum of an antiproton cosmic ray (CR) component calculated on the basis of the nonlinear kinetic model of CR production in supernova remnants (SNRs). The model includes the reacceleration of antiprotons already existing in the interstellar medium as well as the creation of antiprotons in nuclear collisions of accelerated protons with gas nuclei and their subsequent acceleration by SNR shocks. It is shown that the production of antiprotons in SNRs produces a considerable effect in their resultant energy spectrum, making it essentially flatter above 10 GeV so that the spectrum at TeV energies increases by a factor of 5. The calculated antiproton spectrum is consistent with the PAMELA data, which correspond to energies below 100 GeV. As a consistency check, we have also calculated within the same model the energy spectra of secondary nuclei and show that the measured boron-to-carbon ratio is consistent with the significant SNR contribution.

  4. Progenitors of type Ia supernovae

    CERN Document Server

    Maeda, Keiichi

    2016-01-01

    Natures of progenitors of type Ia Supernovae (SNe Ia) have not yet been clarified. There has been long and intensive discussion on whether the so-called single degenerate (SD) scenario or the double degenerate (DD) scenario, or anything else, could explain a major population of SNe Ia, but the conclusion has not yet been reached. With rapidly increasing observational data and new theoretical ideas, the field of studying the SN Ia progenitors has been quickly developing, and various new insights have been obtained in recent years. This article aims at providing a summary of the current situation regarding the SN Ia progenitors, both in theory and observations. It seems difficult to explain the emerging diversity seen in observations of SNe Ia by a single population, and we emphasize that it is important to clarify links between different progenitor scenarios and different sub-classes of SNe Ia.

  5. Mass extinctions and supernova explosions

    CERN Document Server

    Korschinek, Gunther

    2016-01-01

    A nearby supernova (SN) explosion could have negatively influenced life on Earth, maybe even been responsible for mass extinctions. Mass extinction poses a significant extinction of numerous species on Earth, as recorded in the paleontologic, paleoclimatic, and geological record of our planet. Depending on the distance between the Sun and the SN, different types of threats have to be considered, such as ozone depletion on Earth, causing increased exposure to the Sun's ultraviolet radiation, or the direct exposure of lethal x-rays. Another indirect effect is cloud formation, induced by cosmic rays in the atmosphere which result in a drop in the Earth's temperature, causing major glaciations of the Earth. The discovery of highly intensive gamma ray bursts (GRBs), which could be connected to SNe, initiated further discussions on possible life-threatening events in Earth's history. The probability that GRBs hit the Earth is very low. Nevertheless, a past interaction of Earth with GRBs and/or SNe cannot be exclude...

  6. Astrophysics: Echo from an ancient supernova

    Science.gov (United States)

    Pastorello, Andrea; Patat, Ferdinando

    2008-12-01

    Light reflected off a dust cloud in the vicinity of the relic of Tycho Brahe's supernova, whose light first swept past Earth more than four centuries ago, literally sheds light on the nature of this cosmic explosion.

  7. The Supernova Impostor SN 2010da

    Science.gov (United States)

    Binder, Breanna A.; Williams, Benjamin F.; Kong, Albert K. H.; Plucinsky, Paul P.; Gaetz, Terrance J.; Skillman, Evan D.; Dolphin, Andrew E.

    2016-01-01

    Supernova impostors are optical transients that, despite being assigned a supernova designation, do not signal the death of a massive star or accreting white dwarf. Instead, many impostors are thought to be major eruptions from luminous blue variables. Although the physical cause of these eruptions is still debated, tidal interactions from a binary companion has recently gained traction as a possible explanation for observations of some supernova impostors. In this talk, I will discuss the particularly interesting impostor SN 2010da, which exhibits high-luminosity, variable X-ray emission. The X-ray emission is consistent with accretion onto a neutron star, making SN 2010da a likely high mass X-ray binary in addition to a supernova impostor. SN 2010da is a unique laboratory for understanding both binary interactions as drivers of massive star eruptions and the evolutionary processes that create high mass X-ray binaries.

  8. Physical processes in collapse driven supernova

    Energy Technology Data Exchange (ETDEWEB)

    Mayle, R.W.

    1985-11-01

    A model of the supernova explosion is discussed. The method of neutrino transport is discussed, since the explosive mechanism depends on neutrino heating of the material behind the accretion shock. The core region of these exploding stars becomes unstable to convective motions during the supernova evolution. Convective mixing allows more neutrinos to escape from under the neutrinosphere, and thus increases the amount of heating by neutrinos. An approximate method of incorporating convection is described, and some results of including convection in a computer model is presented. Another phenomena is seen in computer simulations of supernova, oscillations in the neutrino luminosity and mass accretion rate onto the protoneutron star. The last topic discussed in this thesis describes the attempt to understand this oscillation by perturbation of the steady state solution to equations approximating the complex physical processes occurring in the late time supernova. 42 refs., 31 figs.

  9. Inside the supernova a powerful convective engine

    CERN Document Server

    Herant, M; Hix, W R; Fryer, C F; Colgate, S A; Marc Herant; Willy Benz; Chris F Fryer; Stirling Colgate

    1994-01-01

    We present an extensive study of the inception of supernova explosions by following the evolution of the cores of two massive stars (15 Msun and 25 Msun) in two dimensions. Our calculations begin at the onset of core collapse and stop several 100 ms after the bounce, at which time successful explosions of the appropriate magnitude have been obtained. (...) Guided by our numerical results, we have developed a paradigm for the supernova explosion mechanism. We view a supernova as an open cycle thermodynamic engine in which a reservoir of low-entropy matter (the envelope) is thermally coupled and physically connected to a hot bath (the protoneutron star) by a neutrino flux, and by hydrodynamic instabilities. (...) In essence, a Carnot cycle is established in which convection allows out-of-equilibrium heat transfer mediated by neutrinos to drive low entropy matter to higher entropy and therefore extracts mechanical energy from the heat generated by gravitational collapse. We argue that supernova explosions are ne...

  10. Detecting supernovae neutrino with Earth matter effect

    CERN Document Server

    Liao, Wei

    2016-01-01

    We study Earth matter effect in oscillation of supernovae neutrinos. We show that detecting Earth matter effect gives an independent measurement of spectra of supernovae neutrinos, i.e. the flavor difference of the spectra of supernovae neutrinos. We study the effect of energy resolution and angular resolution of final electron or positron on detecting the signal of Earth matter effect. We show that varying the widths of energy bins in analysis can change the signal strength of Earth matter effect and the statistical fluctuation. A reasonable choice of energy bins can both suppress the statistical fluctuation and make out a good signal strength relative to the statistical fluctuation. Neutrino detectors with good energy resolution and good angular resolution are therefore preferred so that there are more freedom to vary energy bins and to optimize the signal of Earth matter effect in analyzing events of supernovae neutrinos.

  11. Shock Heated Dust in Young Supernova Remnants

    Science.gov (United States)

    Braun, R.; Strom, R. G.; van der Laan, H.; Greidanus, H.

    Infrared emission in young supernova remnants is interpreted as coming from shock-heated dust. Using models and data from other wavelength regimes, many physical parameters of the remnants can accurately be derived.

  12. Cosmic ray escape from supernova remnants

    CERN Document Server

    Gabici, Stefano

    2011-01-01

    Galactic cosmic rays are believed to be accelerated at supernova remnants via diffusive shock acceleration. Though this mechanism gives fairly robust predictions for the spectrum of particles accelerated at the shock, the spectrum of the cosmic rays which are eventually injected in the interstellar medium is more uncertain and depends on the details of the process of particle escape from the shock. Knowing the spectral shape of these escaping particles is of crucial importance in order to assess the validity of the supernova remnant paradigm for cosmic ray origin. Moreover, after escaping from a supernova remnant, cosmic rays interact with the surrounding ambient gas and produce gamma rays in the vicinity of the remnant itself. The detection of this radiation can be used as an indirect proof of the fact that the supernova remnant was indeed accelerating cosmic rays in the past.

  13. An "archaeological" quest for galactic supernova neutrinos

    CERN Document Server

    Lazauskas, Rimantas; Volpe, Cristina

    2009-01-01

    We explore the possibility to observe the effects of electron neutrinos from past galactic supernovae, through a geochemical measurement of the amount of Technetium 97 produced by neutrino-induced reactions in a Molybdenum ore. The calculations we present take into account the recent advances in our knowledge of neutrino interactions, of neutrino oscillations inside a supernova, of the solar neutrino flux at Earth and of possible failed supernovae. The predicted Technetium 97 abundance is of the order of 10^7 atoms per 10 kilotons of ore, which is close to the current geochemical experimental sensitivity. Of this, 10-20% is from supernovae. Considering the comparable size of uncertainties, more precision in the modeling of neutrino fluxes as well as of neutrino cross sections is required for a meaningful measurement.

  14. A review of type Ia supernova spectra

    CERN Document Server

    Parrent, J; Parthasarathy, M

    2014-01-01

    SN 2011fe was the nearest and best-observed type Ia supernova in a generation, and brought previous incomplete datasets into sharp contrast with the detailed new data. In retrospect, documenting spectroscopic behaviors of type Ia supernovae has been more often limited by sparse and incomplete temporal sampling than by consequences of signal-to-noise ratios, telluric features, or small sample sizes. As a result, type Ia supernovae have been primarily studied insofar as parameters discretized by relative epochs and incomplete temporal snapshots near maximum light. Here we discuss a necessary next step toward consistently modeling and directly measuring spectroscopic observables of type Ia supernova spectra. In addition, we analyze current spectroscopic data in the parameter space defined by empirical metrics, which will be relevant even after progenitors are observed and detailed models are refined.

  15. SN 1054: A pulsar-powered supernova?

    Science.gov (United States)

    Li, Shao-Ze; Yu, Yun-Wei; Huang, Yan

    2015-11-01

    The famous ancient supernova SN 1054 could have been too bright to be explained in the “standard” radioactive-powered supernova scenario. As an alternative attempt, we demonstrate that the spin-down of the newly born Crab pulsar could provide a sufficient energy supply to make SN 1054 visible at daytime for 23 days and at night for 653 days, where a one-zone semi-analytical model is employed. Our results indicate that SN 1054 could be a “normal” cousin of magnetar-powered superluminous supernovae. Therefore, SN 1054-like supernovae could be a probe to uncover the properties of newly born neutron stars, which provide initial conditions for studies on neutron star evolutions.

  16. Diffuse supernova neutrinos at underground laboratories

    Science.gov (United States)

    Lunardini, Cecilia

    2016-06-01

    I review the physics of the Diffuse Supernova Neutrino flux (or Background, DSNB), in the context of future searches at the next generation of neutrino observatories. The theory of the DSNB is discussed in its fundamental elements, namely the cosmological rate of supernovae, neutrino production inside a core collapse supernova, redshift, and flavor oscillation effects. The current upper limits are also reviewed, and results are shown for the rates and energy distributions of the events expected at future liquid argon and liquid scintillator detectors of O(10) kt mass, and water Cherenkov detectors up to a 0.5 Mt mass. Perspectives are given on the significance of future observations of the DSNB, both at the discovery and precision phases, for the investigation of the physics of supernovae and of the properties of the neutrino.

  17. Supernova Shock Breakout from a Red Supergiant

    CERN Document Server

    Schawinski, Kevin; Wolf, Christian; Podsiadlowski, Philipp; Sullivan, Mark; Steenbrugge, Katrien C; Bell, Tony; Roeser, Hermann-Josef; Walker, Emma; Astier, Pierre; Balam, Dave; Balland, Christophe; Basa, Stephane; Carlberg, Ray; Conley, Alex; Fouchez, Dominque; Guy, Julien; Hardin, Delphine; Hook, Isobel; Howell, Andy; Pain, Reynald; Perrett, Kathy; Pritchet, Chris; Regnault, Nicolas; Yi, Sukyoung K

    2008-01-01

    Massive stars undergo a violent death when the supply of nuclear fuel in their cores is exhausted, resulting in a catastrophic `core-collapse' supernova. Such events are usually detected long after the star has exploded. Here we report the first detection of the radiative precursor from a supernova shock before it has reached the surface of a star followed by the initial expansion of the star at the beginning of the explosion. Theoretical models of the ultraviolet light curve show that the progenitor was a red supergiant, as expected for this type of supernova. These observations provide a promising and novel way to probe the physics of core-collapse supernovae and the internal structures of their progenitors.

  18. MDM OSMOS Spectroscopic classification of Supernovae

    Science.gov (United States)

    Bose, Subhash; Dong, Subo; Chen, Ping; Klusmeyer, J.; Prieto, Jose Luis; Shappee, B.; Shields, J.; Brown, J.; Stanek, K. Z.; Kochanek, C.

    2016-11-01

    We report optical spectroscopic classification of supernova candidates 2016hgd (ATel #9651), 2016hli (ATel #9685), CSS161013:015319+171853 and CSS161013:020130+141534 (http://nesssi.cacr.caltech.edu/catalina/AllSN.html).

  19. TYPE Ia SUPERNOVA CARBON FOOTPRINTS

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, R. C.; Nugent, P. [Computational Cosmology Center, Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road MS 50B-4206, Berkeley, CA 94611 (United States); Aldering, G.; Aragon, C.; Bailey, S.; Childress, M.; Fakhouri, H. K.; Hsiao, E. Y.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, 75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M.; Paech, K. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, 53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622 Lyon (France); and others

    2011-12-10

    We present convincing evidence of unburned carbon at photospheric velocities in new observations of five Type Ia supernovae (SNe Ia) obtained by the Nearby Supernova Factory. These SNe are identified by examining 346 spectra from 124 SNe obtained before +2.5 days relative to maximum. Detections are based on the presence of relatively strong C II {lambda}6580 absorption 'notches' in multiple spectra of each SN, aided by automated fitting with the SYNAPPS code. Four of the five SNe in question are otherwise spectroscopically unremarkable, with ions and ejection velocities typical of SNe Ia, but spectra of the fifth exhibit high-velocity (v > 20, 000 km s{sup -1}) Si II and Ca II features. On the other hand, the light curve properties are preferentially grouped, strongly suggesting a connection between carbon-positivity and broadband light curve/color behavior: three of the five have relatively narrow light curves but also blue colors and a fourth may be a dust-reddened member of this family. Accounting for signal to noise and phase, we estimate that 22{sup +10}{sub -6%} of SNe Ia exhibit spectroscopic C II signatures as late as -5 days with respect to maximum. We place these new objects in the context of previously recognized carbon-positive SNe Ia and consider reasonable scenarios seeking to explain a physical connection between light curve properties and the presence of photospheric carbon. We also examine the detailed evolution of the detected carbon signatures and the surrounding wavelength regions to shed light on the distribution of carbon in the ejecta. Our ability to reconstruct the C II {lambda}6580 feature in detail under the assumption of purely spherical symmetry casts doubt on a 'carbon blobs' hypothesis, but does not rule out all asymmetric models. A low volume filling factor for carbon, combined with line-of-sight effects, seems unlikely to explain the scarcity of detected carbon in SNe Ia by itself.

  20. Neutrino-nucleus reactions in supernovae

    Science.gov (United States)

    Dzhioev, Alan A.; Vdovin, A. I.

    2016-01-01

    We study thermal effects on neutrino-nucleus reactions occurring under supernova conditions. The approach we use is based on the QRPA extended to finite temperature by the thermofield dynamics formalism. For the relevant supernova conditions we calculate inelastic neutrino scattering and neutrino absorption cross sections for two sample nuclei, 56Fe and 82Ge. In addition, we apply the approach to examine the rate of neutrino-antineutrino pair emission by hot nuclei.

  1. Neutrino-nucleus reactions in supernovae

    Directory of Open Access Journals (Sweden)

    Dzhioev Alan A.

    2016-01-01

    Full Text Available We study thermal effects on neutrino-nucleus reactions occurring under supernova conditions. The approach we use is based on the QRPA extended to finite temperature by the thermofield dynamics formalism. For the relevant supernova conditions we calculate inelastic neutrino scattering and neutrino absorption cross sections for two sample nuclei, 56Fe and 82Ge. In addition, we apply the approach to examine the rate of neutrino-antineutrino pair emission by hot nuclei.

  2. Supernova neutrino oscillations: What do we understand?

    Energy Technology Data Exchange (ETDEWEB)

    Dighe, Amol, E-mail: amol@theory.tifr.res.i [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 (India)

    2010-01-01

    We summarize our current understanding of the neutrino flavor conversions inside a core collapse supernova, clarifying the important role played by the 'collective effects' in determining flavor conversion probabilities. The potentially observable {nu}{sub e} and {nu}-bar {sub e} spectra may help us identify the neutrino mixing scenario, distinguish between primary flux models, and learn more about the supernova explosion.

  3. Collective flavor transitions of supernova neutrinos

    CERN Document Server

    Sigl, Guenter; Esteban-Pretel, Andreu; Pastor, Sergio; Mirizzi, Alessandro; Raffelt, Georg G; Serpico, Pasquale D

    2009-01-01

    We give a very brief overview of collective effects in neutrino oscillations in core collapse supernovae where refractive effects of neutrinos on themselves can considerably modify flavor oscillations, with possible repercussions for future supernova neutrino detection. We discuss synchronized and bipolar oscillations, the role of energy and angular neutrino modes, as well as three-flavor effects. We close with a short summary and some open questions.

  4. The SuperNova Early Warning System

    OpenAIRE

    Scholberg, K.

    2008-01-01

    A core collapse in the Milky Way will produce an enormous burst of neutrinos in detectors world-wide. Such a burst has the potential to provide an early warning of a supernova's appearance. I will describe the nature of the signal, the sensitivity of current detectors, and SNEWS, the SuperNova Early Warning System, a network designed to alert astronomers as soon as possible after the detected neutrino signal.

  5. Close binary white dwarfs and supernovae IA

    Directory of Open Access Journals (Sweden)

    R. Napiwotzki

    2004-01-01

    Full Text Available Informamos sobre el estado actual de los \\surveys" de velocidades radiales para binarias de enanas blancas (degeneradas dobles - DDs incluyendo SPY (Exploraci on ESO de progenitoras de supernovas Ia que recien- temente se llevaron a cabo en el VLT. Una amplia muestra de DDs nos permitir a poner fuertes restricciones sobre las fases evolutivas de los sistemas progenitores de binarias cercanas y tambi en llevar a cabo pruebas observacionales del escenario DD para supernovas de tipo Ia.

  6. Overview of the nearby supernova factory

    Energy Technology Data Exchange (ETDEWEB)

    Aldering, Greg; Adam, Gilles; Antilogus, Pierre; Astier, Pierre; Bacon, Roland; Bongard, S.; Bonnaud, C.; Copin, Yannick; Hardin, D.; Howell, D. Andy; Lemmonnier, Jean-Pierre; Levy, J.-M.; Loken, S.; Nugent, Peter; Pain, Reynald; Pecontal, Arlette; Pecontal, Emmanuel; Perlmutter, Saul; Quimby, Robert; Schahmaneche, Kyan; Smadja, Gerard; Wood-Vasey, W. Michael

    2002-07-29

    The Nearby Supernova Factory (SNfactory) is an international experiment designed to lay the foundation for the next generation of cosmology experiments (such as CFHTLS, wP, SNAP and LSST) which will measure the expansion history of the Universe using Type Ia supernovae. The SNfactory will discover and obtain frequent lightcurve spectrophotometry covering 3200-10000 {angstrom} for roughly 300 Type Ia supernovae at the low-redshift end of the smooth Hubble flow. The quantity, quality, breadth of galactic environments, and homogeneous nature of the SNfactory dataset will make it the premier source of calibration for the Type Ia supernova width-brightness relation and the intrinsic supernova colors used for K-correction and correction for extinction by host-galaxy dust. This dataset will also allow an extensive investigation of additional parameters which possibly influence the quality of Type Ia supernovae as cosmological probes. The SNfactory search capabilities and follow-up instrumentation include wide-field CCD imagers on two 1.2-m telescopes (via collaboration with the Near Earth Asteroid Tracking team at JPL and the QUEST team at Yale), and a two-channel integral-field-unit optical spectrograph/imager being fabricated for the University of Hawaii 2.2-m telescope. In addition to ground-based follow-up, UV spectra for a subsample of these supernovae will be obtained with HST. The pipeline to obtain, transfer via wireless and standard internet, and automatically process the search images is in operation. Software and hardware development is now underway to enable the execution of follow-up spectroscopy of supernova candidates at the Hawaii 2.2-m telescope via automated remote control of the telescope and the IFU spectrograph/imager.

  7. Neutrino oscillations in core-collapse supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Meng-Ru [TU Darmstadt (Germany); University of Minnesota, MN (United States); Huther, Lutz [TU Darmstadt (Germany); Fischer, Tobias; Martinez-Pinedo, Gabriel [TU Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Qian, Yong-Zhong [University of Minnesota, MN (United States)

    2013-07-01

    Neutrino oscillations play an important role in determining the spectra of neutrinos emitted from core-collapse supernova and must be considered in the analysis of supernova neutrino detection to understand both the supernova dynamics and the unknown neutrino mass hierarchy. We have studied neutrino oscillations in supernovae using the emission spectra of neutrinos and the dynamically evolving supernova density profile from a state-of-the-art supernova model. We find that in this model, different regions of neutrino oscillations are well separated. Collective neutrino oscillations happen at the innermost part such that the spectra of electron neutrinos and mu/tau neutrinos are partly swapped for the first few seconds in the cooling phase. Then, the high and low MSW resonances that occur after collective oscillations are both adiabatic. Using these results, we find that in this model, neutrino oscillations have little effect on the nucleosynthesis in the neutrino-driven winds. However, the detection of such a signal could possibly allow us to differentiate the neutrino mass hierarchy and to extract the shock revival time.

  8. Design of Smith-Purcell emitter in femtosecond accelerator

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on the femtosecond accelerator device,we are planning to build a broad band and tunable THz source using the Smith-Purcell tadiation mechanism.Coherent Smith-Purcell radiation could be achieved owing to the super-short bunch produced in the device.To shorten the distance between the beam and grating,we use Transport to match the beta function producing a sheet beam on the grating surface.The optimization of grating length,groove depth and groove width are given in the paper.Then the radiation power for the shallow and deep grating using these parameters are presented.The detection devices and methods are also briefly discussed.

  9. Adam Smith y la teoría social

    Directory of Open Access Journals (Sweden)

    Jorge López Lloret

    2014-11-01

    Full Text Available El presente artículo estudia las ideas sociales de Adam Smith en su contexto histórico.Como instrumentos de análisis recurre a las nociones de «micro-sociología» y «macro-sociología», así como al enfoque dramatúrgico de la sociología de Goffman. Smith desarrolló un pensamiento social «micro» en La teoría de los sentimientos morales y otro «macro» en La riqueza de las naciones. Identificó además al objeto (como producto de la manufactura y como bien de consumo como el elemento de enlace entre ambas dimensiones, en un doble sentido: 1 como parte de nuestra puesta en escena cotidiana, y 2 como mediador de las relaciones sociales en unos contextos urbanos cada vez más complicados.

  10. Adam Smith and the new era of China

    Directory of Open Access Journals (Sweden)

    Aníbal Carlos Zottele

    2013-01-01

    Full Text Available ural area has been the quiet main character of China’s economic development. The history of this thousand-year-old culture seems to be exempted from further comments about its role. Its importance has been strongly expressed during crisis which institutions of that great nation in XX century were shook. Agricultural sector was the key in modernization period initiated in 1980 even in the later phases. Agriculture preponderance as progress support of the nations is presented by Scottish thinker Adam Smith in his work An Inquiry into the Nature and Causes of the Wealth of Nations. The status of Chinese development in XVII y XVIII centuries has been characterized in this document as well as the natural order of progress against unnatural or retrograde order followed by the Netherlands, in that time the country that had achieved higher levels growth in Europe. Apparently, at present, China repeats its old experiences by concentrating on the path praised by Smith.

  11. Improving performance using cascade control and a Smith predictor.

    Science.gov (United States)

    Kaya, I

    2001-01-01

    Many investigations have been done on tuning proportional-integral-derivative (PID) controllers in single-input single-output (SISO) systems. However, only a few investigations have been carried out on tuning PID controllers in cascade control systems. In this paper, a new approach, namely the use of a Smith predictor in the outer loop of a cascade control system, is investigated. The method can be used in temperature control problems where the secondary part of the process (the inner loop) may have a negligible delay while the primary loop (the outer loop) has a time-delay. Two different approaches, including an autotuning method, to find the controller parameters are proposed. It is shown by some examples that the proposed structure as expected can provide better performance than conventional cascade control, a Smith predictor scheme or single feedback control system.

  12. Smith-Purcell Radiation in View of Particle Beam Diagnostics

    CERN Document Server

    Kube, G

    2003-01-01

    The development of the next generation high quality electron beams which are necessary for future high luminosity linear colliders and short wavelengths free electron lasers requires sensitive and non-destructive beam diagnostic techniques. In this context Smith-Purcell radiation which is generated when a charged particle beam passes close to the surface of a periodic structure (diffraction grating) is under discussion as a compact and inexpensive beam profile monitor. In order to study the basic emission process of Smith-Purcell radiation also in view of possible applications for particle beam diagnostics, experimental studies were performed at the Mainz Microtron MAMI in the visible spectral region with a microfocused 855 MeV electron beam. The radiation was separated from background components, as diffracted synchrotron radiation and transition radiation generated by electrons scratching the grating surface, by exploiting their specific emission characteristics. These are the narrow emission cone in the ...

  13. Defenses and morality: Adam Smith, Sigmund Freud, and contemporary psychoanalysis.

    Science.gov (United States)

    Gabrinetti, Paul A; Özler, Sule

    2014-10-01

    In this paper we follow the development and transmission of moral learning from Adam Smith's impartial spectator to Sigmund Freud's superego and then to contemporary psychoanalysis. We argue that defenses are an integral component in the acquisition of any moral system. Elaborating on this argument, we assert that there is a progression from defensive systems that are "closed" to defensive systems that are "open," as defined in a recent work by Novick and Novick. The former system is "static, avoids reality, and is characterized by power dynamics, sadomasochism, and omnipotent defense." The latter, on the other hand, is a system that allows for "joy, creativity, spontaneity, love and it is attuned to reality." Furthermore, while Smith and Freud's systems are more one-person systems of defense, contemporary psychoanalysis has moved to more of a two-person system.

  14. Empathy's purity, sympathy's complexities; De Waal, Darwin and Adam Smith.

    Science.gov (United States)

    van der Weele, Cor

    2011-07-01

    Frans de Waal's view that empathy is at the basis of morality directly seems to build on Darwin, who considered sympathy as the crucial instinct. Yet when we look closer, their understanding of the central social instinct differs considerably. De Waal sees our deeply ingrained tendency to sympathize (or rather: empathize) with others as the good side of our morally dualistic nature. For Darwin, sympathizing was not the whole story of the "workings of sympathy"; the (selfish) need to receive sympathy played just as central a role in the complex roads from sympathy to morality. Darwin's understanding of sympathy stems from Adam Smith, who argued that the presence of morally impure motives should not be a reason for cynicism about morality. I suggest that De Waal's approach could benefit from a more thorough alignment with the analysis of the workings of sympathy in the work of Darwin and Adam Smith.

  15. Type Ia supernova rate at a redshift of ­0.1

    DEFF Research Database (Denmark)

    Blanc ...[et al], G.; Andersen, J.

    2004-01-01

    stars: supernovae: general; galaxies: evolution; cosmology: miscellaneous; methods: observational......stars: supernovae: general; galaxies: evolution; cosmology: miscellaneous; methods: observational...

  16. Free electron laser based on the Smith-Purcell radiation

    Institute of Scientific and Technical Information of China (English)

    WANG Ming-hong; XIAO Xiao-guang; YU Hui-shan; MENG Xian-zhu

    2006-01-01

    A Smith-Purcell (SP) free electron laser (FEL) ,composed of a metallic diffraction flat grating,an open cylindrical mirror cavity and a relativistic sheet electron beam with moderate energy, is presented. The characteristics of this device are studied by theoretical analysis, experimental measurements and particle-in-cell (PIC) simulation method. Results indicate that the coherent radiation with an output peak power up to 50 MW at millimeter wavelengths can be generated by using relativistic electron beam of moderate energy.

  17. Page Smith: Founding Cowell College and UCSC, 1964-1973

    OpenAIRE

    Smith, Page; Jarrell, Randall; Regional History Project, UCSC Library

    1996-01-01

    This oral history chronicles the late Page Smith's experiences as founding provost of the campus's first college and his major contributions in shaping the college system here. His narration includes chapters on student culture in the 1960s and 1970s, the pass/fail grading system, his educational philosophy, town/gown relations, campus architecture, the History of Consciousness Program, his relationship with founding Chancellor Dean E. McHenry, arts on the campus and the role of his wife, Elo...

  18. Building Energy Audit Report for Camp Smith, HI

    Energy Technology Data Exchange (ETDEWEB)

    Chvala, William D.; De La Rosa, Marcus I.; Brown, Daryl R.; Dixon, Douglas R.

    2010-09-30

    A detailed energy assessment was performed by a team of engineers from Pacific Northwest National Laboratory (PNNL) under contract to the Department of Energy/Federal Energy Management program (FEMP). The effort used the Facility Energy Decision System (FEDS) model to determine how energy is consumed at Camp Smith, identify the most cost-effective energy retrofit measures, and calculate the potential energy and cost savings. This report documents the results of that assessment.

  19. Moore-Smith Convergence in L-Fuzzifying Topological Spaces

    Institute of Scientific and Technical Information of China (English)

    Wei YAO; Ling Xia LU

    2011-01-01

    This paper presents a definition of L-fuzzifying nets and the related L-fuzzifying generalized convergence spaces.The Moore-Smith convergence is established in L-fuzzifying topology.It is shown that the category of L-fuzzifying generalized convergence spaces is a cartesianclosed topological category which embeds the category of L-fuzzifying topological spaces as a reflective subcategory.

  20. GlaxoSmithKline: A merger too far?

    OpenAIRE

    Bernardo Batiz-Lazo

    2004-01-01

    This teaching case study summarises events leading to the creation of a global pharmaceutical giant and the early years of its performance while inviting readers to consider the process of growth through mergers and acquisitions as a general strategy. The case also looks at the expectations, deliberations and motivation of managers and stakeholders in doing so. The case invites readers to reflect on whether more mergers are to be the future of GlaxoSmithKline.

  1. On liberty and crime: Adam Smith and John Stuart Mill

    OpenAIRE

    Ruggiero, Vincenzo

    2008-01-01

    Abstract The author considers some of the works produced by Adam Smith and John Stuart Mill, who from different perspectives discuss notions such as transgression, deviance and crime. It is argued that the analysis of power crime may immensely benefit from an excavation into economics, for its concern about the creation and acquisition of wealth, the legitimacy of certain conducts as opposed to others, and ultimately the circumstances in which competition and enterpris...

  2. Buffer-stock saving in a Krusell-Smith world

    OpenAIRE

    Christopher D Carroll; Slacalek, Jiri; Tokuoka, Kiichi

    2014-01-01

    A large body of microeconomic evidence supports Friedman (1957)'s proposition that household income can be reasonably well described as having both transitory and permanent components. We show how to modify the widely-used macroeconomic model of Krusell and Smith (1998) to accommodate such a microeconomic income process. Our incorporation of substantial permanent income shocks helps our model to explain a substantial part of the large degree of empirical wealth heterogeneity that is unexplain...

  3. Supernova remnants: the X-ray perspective

    Science.gov (United States)

    Vink, Jacco

    2012-12-01

    Supernova remnants are beautiful astronomical objects that are also of high scientific interest, because they provide insights into supernova explosion mechanisms, and because they are the likely sources of Galactic cosmic rays. X-ray observations are an important means to study these objects. And in particular the advances made in X-ray imaging spectroscopy over the last two decades has greatly increased our knowledge about supernova remnants. It has made it possible to map the products of fresh nucleosynthesis, and resulted in the identification of regions near shock fronts that emit X-ray synchrotron radiation. Since X-ray synchrotron radiation requires 10-100 TeV electrons, which lose their energies rapidly, the study of X-ray synchrotron radiation has revealed those regions where active and rapid particle acceleration is taking place. In this text all the relevant aspects of X-ray emission from supernova remnants are reviewed and put into the context of supernova explosion properties and the physics and evolution of supernova remnants. The first half of this review has a more tutorial style and discusses the basics of supernova remnant physics and X-ray spectroscopy of the hot plasmas they contain. This includes hydrodynamics, shock heating, thermal conduction, radiation processes, non-equilibrium ionization, He-like ion triplet lines, and cosmic ray acceleration. The second half offers a review of the advances made in field of X-ray spectroscopy of supernova remnants during the last 15 year. This period coincides with the availability of X-ray imaging spectrometers. In addition, I discuss the results of high resolution X-ray spectroscopy with the Chandra and XMM-Newton gratings. Although these instruments are not ideal for studying extended sources, they nevertheless provided interesting results for a limited number of remnants. These results provide a glimpse of what may be achieved with future microcalorimeters that will be available on board future X

  4. Manipulating Smith-Purcell Emission with Babinet Metasurfaces

    Science.gov (United States)

    Wang, Zuojia; Yao, Kan; Chen, Min; Chen, Hongsheng; Liu, Yongmin

    2016-10-01

    Swift electrons moving closely parallel to a periodic grating produce far-field radiation of light, which is known as the Smith-Purcell effect. In this letter, we demonstrate that designer Babinet metasurfaces composed of C -aperture resonators offer a powerful control over the polarization state of the Smith-Purcell emission, which can hardly be achieved via traditional gratings. By coupling the intrinsically nonradiative energy bound at the source current sheet to the out-of-plane electric dipole and in-plane magnetic dipole of the C -aperture resonator, we are able to excite cross-polarized light thanks to the bianisotropic nature of the metasurface. The polarization direction of the emitted light is aligned with the orientation of the C -aperture resonator. Furthermore, the efficiency of the Smith-Purcell emission from Babinet metasurfaces is significantly increased by 84%, in comparison with the case of conventional gratings. These findings not only open up a new way to manipulate the electron-beam-induced emission in the near-field region but also promise compact, tunable, and efficient light sources and particle detectors.

  5. Adam Smith om forholdet mellem moralske fornemmelser og naturen

    DEFF Research Database (Denmark)

    Huggler, Lise Oxenbøll

    2008-01-01

    I The Theory of Moral Sentiments giver Adam Smith en fremstilling af, hvordan mennesket i sam­fundslivet udvikler moralske fornemmelser og af den betydning, disse har for menneskers følelses- og handlingsliv. Her er synssansen afgørende, idet den sætter mennesket i stand til rumligt lokaliser......­bart at betragte andre menneskers opførsel såvel som andre menneskers reaktioner på ens egen opførsel. Den sætter derved på en entydig måde mennesket i stand til at forholde sig til sig selv og til andre mennesker. På dette grundlag opstiller Smith en række psykologiske reaktionsmønstre. Ikke desto mindre påkalder...... han jævnligt bl.a. naturen som en metafysisk entitet. Der skal her argumenteres for, at de metafysiske begreber har til opgave at skabe den sammenhæng i menneskelivet, som kausale reaktioner i sig selv ikke giver. I forlængelse af dette peges der på, at Smith synes at hævde, at mennesket i samfundet...

  6. Antioxidant and antiproliferative activity of Granny Smith apple pomace

    Directory of Open Access Journals (Sweden)

    Savatović Slađana M.

    2008-01-01

    Full Text Available Granny Smith apple pomace was subjected to evaluation as valuable source of antioxidant and anticancer phytochemicals on the basis of its content in phenolic compounds, antioxidant and antiproliferative activity. The total cotent of phenolics, flavonoids and flavan-3-ols in apple pomace determined spectrophotometrically, was 7.02 mg/g, 0.51 mg/g and 8.80 mg/g. Major phenolics (phenolic acids, flavan-3-ols, flavonoids and dihydrochalcons in apple pomace were identified and quantified by HPLC. The antioxidant activity of apple pomace on stable 1,1-diphenyl-2-picrylhydrazyl (DPPH and reactive hydroxyl radicals, was investigated by electron spin resonance (ESR spectroscopy. The IC50 DPPH and IC50 OH values of Granny Smith apple pomace were 9.51 mg/ml and 29.17 mg/ml, respectively. The antiproliferative activities of apple pomace on cervix epitheloid carcinoma (HeLa, colon adenocarcinoma (HT-29 and breast adenocarcinoma (MCF7 cell lines were determined according to the MTT (3-(4,5-dimethylthiazol-2-yl- 2,5-diphenyltetrazolium bromide colorimetric assay. The IC50 HeLa , IC50 HT-29 and IC50 MCF7 values of Granny Smith apple pomace were 26.40 mg/ml, 22.47 mg/ml and 21.26 mg/ml, respectively. The significant correlations between antioxidant activities and antiproliferative activities were established (p<0.05.

  7. Difficult airway in a patient with Marshall-Smith syndrome.

    Science.gov (United States)

    Antila, H; Laitio, T; Aantaa, R; Silvoniemi, P; Pakkanen, A

    1998-01-01

    Marshall-Smith syndrome is a rare clinical disorder characterized by accelerated bone maturation, dysmorphic facial features, airway abnormalities and death in early infancy because of respiratory complications. Although patients with Marshall-Smith syndrome have several features with potential anaesthetic problems, previous reports about anaesthetic management of these patients do not exist. We present a case, in which severe hypoxia developed rapidly after routine anaesthesia induction in an eight-month-old male infant with this syndrome. After several unsuccessful attempts the airway was finally secured by blind oral intubation. After 2 weeks, laryngeal anatomy was examined with fibreoptic laryngoscopy which revealed significant laryngomalacia. Laryngoscopy was performed without problems with ketamine anaesthesia and spontaneous breathing. The possibility of a compromised airway should always be borne in mind when anaesthetizing patients with Marshall-Smith syndrome. Anaesthesia maintaining spontaneous breathing is safest for children with this syndrome. If tracheal intubation or muscle relaxation is required, precautions are needed to maintain a patent airway. Muscle relaxants should possibly be avoided before intubation.

  8. Starry Campus: Reducing Light Pollution at Smith College

    Science.gov (United States)

    Brenon, Alexandria

    2017-01-01

    This is the start of a program to teach Smith College students about the dangers posed by light pollution and inspire them to help make Smith a better dark sky area. This will focus both on general astronomy education to catch their interest and speciic light pollution information as well. My advisor is creating an initiative for dark skies education and preservation on college campuses, with this as the pilot program. College students can help both on campus and off when they will be able to take what they learn to inform their decisions about lighting when they move out on their own. The ultimate goal is to convince Smith College to make the changes it needs to reduce its light pollution as well as to motivate its students to learn more about astronomy and light pollution. I am developing an education and outreach program using venues such as house teas, lectures, and meetings to teach other students, the staff, and faculty about the issue. I am also working with existing clubs and organizations on campus such as the Green Team, the landscape studies department, and the Center for the Environment, Ecological Design, and Sustainability. This will help to develop campus lighting standards. These lighting standards will be proposed to the college, as there are no current standards in place for lighting around campus.

  9. Neutrinos from type-II supernovae and the neutrino-driven supernova mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Janka, H.T. [Max-Planck-Institut fuer Astrophysik, Garching (Germany)

    1996-11-01

    Supernova 1987A has confirmed fundamental aspects of our theoretical view of type-II supernovae: Type-II supernovae are a consequence of the collapse of the iron core of a massive evolved star and lead to the formation of a neutron star or black hole. This picture is most strongly supported by the detection of electron antineutrinos in the IMB and Kamiokande II experiments in connection with SN 1987A. However, the mechanism causing the supernova explosion is not yet satisfactorily understood. In this paper the properties of the neutrino emission from supernovae and protoneutron stars will be reviewed; analytical estimates will be derived and results of numerical simulations will be shown. It will be demonstrated that the spectral distributions of the emitted neutrinos show clear and systematic discrepancies compared with thermal (black body-type) emission. This must be taken into account when neutrino observations from supernovae are to be interpreted, or when implications of the neutrino emission on nucleosynthesis processes in mantle and envelope of the progenitor star are to be investigated. Furthermore, the influence of neutrinos on the supernova dynamics will be discussed, in particular their crucial role in causing the explosion by Wilson`s neutrino-driven delayed mechanism. Possible implications of convection inside the newly born neutron star and between surface and the supernova shock will be addressed and results of multi-dimensional simulations will be presented. (author) 7 figs., 1 tab., refs.

  10. Final Report - Conservation & Renewable Energy Potential Study For Smith River Rancheria

    Energy Technology Data Exchange (ETDEWEB)

    Greg Retzlaff

    2007-07-01

    In January 2006 the Smith River Rancheria (SRR), located in Smith River, California, contracted with the team of Strategic Energy Solutions (SES) and Evergreen NRG to conduct a study for the community. The objective of the study was to identify renewable generation opportunities that would facilitate Rancheria energy independence through SRR owned and operated power projects. These generation facilities were to be located either on or near the reservation. Specifically, the Rancheria was interested in the viability of generating electric power using biomass and wind fuel resources. Initial research identified that a very small portion of the community's energy could be offset by renewable energy generation due to the low solar resource in this area, and the lack of significant wind or biomass resources on or near reservation land. Some larger projects were identified which offered little or no benefit to the Rancheria. As a result, the scope of this study was changed in October 2006 to focus on energy efficiency opportunities for key reservation facilities, with a continued analysis of smaller renewable energy opportunities within reservation boundaries. The consulting team initially performed a resource analysis for biomass and solar generation opportunities in the region of the Rancheria. It was quickly concluded that none of these options would yield renewable power for the Rancheria at costs competitive with current utility sources, and that any larger installations would require substantial funding that may not be available. Having made these conclusions early on, the study effort was redirected and the team investigated each of the major Rancheria buildings to look for solar, wind and conservation opportunities. The buildings were audited for energy use and the roof areas were examined for exposure of solar radiation. Wind resources were also investigated to determine if smaller wind turbines would offer power generation at a reasonable cost.

  11. Type Ia Supernova Progenitors, Environmental Effects and Cosmic Supernova Rates

    CERN Document Server

    Nomoto, K; Hachisu, I; Kato, M; Kobayashi, C; Tsujimoto, T; Nomoto, Ken'ichi; Umeda, Hideyuki; Hachisu, Izumi; Kato, Mariko; Kobayashi, Chiaki; Tsujimoto, Takuji

    1999-01-01

    Relatively uniform light curves and spectral evolution of Type Ia supernovae (SNe Ia) have led to the use of SNe Ia as a ``standard candle'' to determine cosmological parameters, such as the Hubble constant, the density parameter, and the cosmological constant. Whether a statistically significant value of the cosmological constant can be obtained depends on whether the peak luminosities of SNe Ia are sufficiently free from the effects of cosmic and galactic evolutions. Here we first review the single degenerate scenario for the Chandrasekhar mass white dwarf (WD) models of SNe Ia. We identify the progenitor's evolution and population with two channels: (1) the WD+RG (red-giant) and (2) the WD+MS (near main-sequence He-rich star) channels. In these channels, the strong wind from accreting white dwarfs plays a key role, which yields important age and metallicity effects on the evolution. We then address the questions whether the nature of SNe Ia depends systematically on environmental properties such as metalli...

  12. Supernovae under microscope: how supernovae overlap to form superbubbles

    CERN Document Server

    Yadav, Naveen; Sharma, Prateek; Nath, Biman B

    2016-01-01

    We explore the formation of superbubbles through energy deposition by multiple supernovae (SNe) in a uniform medium. We use total energy conserving, 3-D hydrodynamic simulations to study how SNe correlated in space and time create superbubbles. While isolated SNe fizzle out completely by $\\sim 1$ Myr due to radiative losses, for a realistic cluster size it is likely that subsequent SNe go off within the hot/dilute bubble and sustain the shock till the cluster lifetime. We scan the parameter space of ISM density ($n_{g0}$), number of SNe ($N_{\\rm OB}$), and star cluster radius ($r_{\\rm cl}$) to study the conditions for the formation of an overpressured (super)bubble. For realistic cluster sizes, we find that the bubble remains overpressured only if, for a given $n_{g0}$, $N_{\\rm OB}$ is sufficiently large. While most of the input energy is still lost radiatively, superbubbles can retain up to $\\sim 5-10\\%$ of the input energy in form of kinetic+thermal energy till 10 Myr for ISM density $n_{g0} \\approx 1$ cm$^...

  13. 施密斯(Smith)预估器算法研究%Smith Foreordaining Estimated Implement Arithmetic Research

    Institute of Scientific and Technical Information of China (English)

    熊珍凯

    2007-01-01

    论述了施密斯(smith)预估的原理,从解决纯滞后环节的角度出发,研究了Smith预估补偿器的设计及其改进,并对设计进行了仿真验证.结果表明,改进型的Smith预估补偿器误差小,鲁棒性强,有很好的推广价值.

  14. Site study plan for Transportation, Deaf Smith County Site, Texas: Preliminary draft

    Energy Technology Data Exchange (ETDEWEB)

    1987-06-01

    This site study plan describes transportation field studies to be conducted during the characterization of the Deaf Smith County, Texas, site for the US Department of Energy's Salt Repository Project. The studies are needed to identify and assess potential project impacts to transportation infrastructure and systems in the project vicinity and along potential transportation routes to the site across the State of Texas. The studies are also needed to locate and design project transportation facilities, and to evaluate and design impact mitigation. After identifying the transportation information requirements needed to comply with Federal, State, and local regulations and repository program requirements, the site study plan describes the study design and rationale, the field data collection procedures and equipment, the data analysis methods and application of results, the data management strategy, the schedule of field activities, the management of the study, and the study's quality assurance program. The field data collection activities are organized into programs for the characterization of site vicinity rail corridors and highway corridors, characterization of alternative statewide transportation routes, monitoring of site characterization effects on transportation, characterization of aircraft overflight patterns and hazardous material transportation patterns, and assessment of emergency response preparedness along alternative statewide transportation routes. 34 refs., 10 figs., 2 tabs.

  15. The physics of core collapse supernovae

    Science.gov (United States)

    Swesty, Frank Douglas

    1993-01-01

    I have developed an equation of state (EOS) for hot, dense matter that is intended specifically for use in radiation hydrodynamic simulations of supernovae, proto-neutron star cooling, and neutron stars. This EOS makes use of an adjustable nucleon-nucleon interaction that allows for the input of various nuclear force parameters that are not well determined by laboratory measurements. Properties of the EOS as a function of these input parameters were studied and comparisons were made to another EOS that is currently used in stellar collapse simulations. Using this EOS I have conducted simulations of core collapse supernovae with several ideas in mind. First, I have attempted to delineate role of the incompressibility of dense matter in supernovae. I have conducted a parameter study in which the compression modulous of bulk nuclear matter was varied and have found some new and surprising results. When the EOS is constrained by the observed mass of 1.44M(solar mass) for one of the components of the binary pulsar system PSR1913+16, the 'stiffness' of the EOS no longer plays a role in the shock dynamics of the supernova. Secondly, I varied the symmetry energy coefficients in the EOS to determine the role of these coefficients in supernovae. I have found that the symmetry energy behavior of the EOS has potentially observable effects and may play an important role in determining the efficacy of the late-time heating mechanism for the explosion and the stability of the post-bounce core against convection. Finally, I have developed an implicit, general relativistic, radiation hydrodynamics algorithm for the numerical simulation of supernovae. By allowing simulation timesteps to exceed the Courant timescale, this algorithm makes practical high resolution simulations of supernovae to late times. I discuss this algorithm and the associated computer code along with code verification tests and an example of a late-time calculation.

  16. Supernova Dust at Sub-micrometer Scales

    Science.gov (United States)

    Nittler, Larry; Stroud, R. M.

    2006-06-01

    Meteorites contain nanometer to micrometer stardust grains, which formed in pre-solar generations of stars and exhibit large isotopic anomalies that reflect the nuclear processes that occurred in their individual parent stars [1]. Supernovae of Type II have been identified as the sources of much of the stardust, including grains of SiC, Si3N4, graphite and Mg2SiO4. Although, the isotopic compositions of many elements in these grains point unambiguously to supernova nucleosynthesis processes [2], the data require extensive and heterogeneous mixing of disparate nuclear burning zones. A recent study found that individual 200 nm TiC sub-grains within a 12 micron supernova graphite grain have uniform Ti isotopic composition but a range of O isotopic ratios [3]. New microanalysis techniques allow us to correlate the physical microstructures of supernova grains with isotopic composition, e.g., SiC and Si3N4, providing a sub-micron view of condensation processes in supernova ejecta. Results on two SiC grains indicate that micron-sized SiC grains from supernovae consist of assemblages of smaller crystallites with some evidence of radiation and/or shock processing. This is in strong contrast to SiC grains from AGB stars, which are typically single euhedral crystals [4]. The Si, C and N isotopic compositions of the grains are highly uniform, in contrast to the model of [5], which predicts strong isotopic gradients in supernova-derived SiC grains.This work is supported by NASA.[1] Clayton D. D. and Nittler L. R. (2004) ARAA, 42, 39-78.[2] Nittler L. R., et al. (1996) ApJ, 462, L31-34.[3] Stadermann F. J., et al. (2005) GCA, 69, 177-188.[4] Daulton T. L., et al. (2002) Science, 296, 1852-1855.[5] Deneault E. A.-N., et al. (2003) ApJ, 594, 312-325.

  17. Welcome to the Walnut Creek Nonbreeding Bird Monitoring Project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a summary of the bird monitoring project at Walnut Creek National Wildlife Refuge (Neal Smith National Wildlife Refuge). The refuge is divided into 28...

  18. The Supernovae Analysis Application (SNAP)

    Science.gov (United States)

    Bayless, Amanda J.; Fryer, Chris L.; Wollaeger, Ryan; Wiggins, Brandon; Even, Wesley; de la Rosa, Janie; Roming, Peter W. A.; Frey, Lucy; Young, Patrick A.; Thorpe, Rob; Powell, Luke; Landers, Rachel; Persson, Heather D.; Hay, Rebecca

    2017-09-01

    The SuperNovae Analysis aPplication (SNAP) is a new tool for the analysis of SN observations and validation of SN models. SNAP consists of a publicly available relational database with observational light curve, theoretical light curve, and correlation table sets with statistical comparison software, and a web interface available to the community. The theoretical models are intended to span a gridded range of parameter space. The goal is to have users upload new SN models or new SN observations and run the comparison software to determine correlations via the website. There are problems looming on the horizon that SNAP is beginning to solve. For example, large surveys will discover thousands of SNe annually. Frequently, the parameter space of a new SN event is unbounded. SNAP will be a resource to constrain parameters and determine if an event needs follow-up without spending resources to create new light curve models from scratch. Second, there is no rapidly available, systematic way to determine degeneracies between parameters, or even what physics is needed to model a realistic SN. The correlations made within the SNAP system are beginning to solve these problems.

  19. The Supernovae Analysis Application (SNAP)

    CERN Document Server

    Bayless, Amanda J; Wiggins, Brandon; Even, Wesley; Wollaeger, Ryan; de la Rosa, Janie; Roming, Peter W A; Frey, Lucy; Young, Patrick A; Thorpe, Rob; Powell, Luke; Landers, Rachel; Persson, Heather D; Hay, Rebecca

    2016-01-01

    The SuperNovae Analysis aPplication (SNAP) is a new tool for the analysis of SN observations and validation of SN models. SNAP consists of an open source relational database with (a) observational light curve, (b) theoretical light curve, and (c) correlation table sets, statistical comparison software, and a web interface available to the community. The theoretical models are intended to span a gridded range of parameter space. The goal is to have users to upload new SN models or new SN observations and run the comparison software to determine correlations via the web site. There are looming problems on the horizon that SNAP begins to solve. Namely, large surveys will discover thousands of SNe annually. Frequently, the parameter space of a new SN event is unbounded. SNAP will be a resource to constrain parameters and determine if an event needs follow-up without spending resources to create new light curve models from scratch. Secondly, there is not a rapidly available, systematic way to determine degeneracie...

  20. Fingerprints of a Local Supernova

    CERN Document Server

    Manuel, Oliver

    2009-01-01

    The results of precise analysis of elements and isotopes in meteorites, comets, the Earth, the Moon, Mars, Jupiter, the solar wind, solar flares, and the solar photosphere since 1960 reveal fingerprints of a local supernova (SN), undiluted by interstellar material. Heterogeneous SN debris formed the planets. The Sun formed on the neutron (n) rich SN core. The ground-state masses of nuclei reveal repulsive n-n interactions that trigger n-emission and a series of nuclear reactions that generate solar luminosity, the solar wind, and the measured flux of solar neutrinos. The location of the Sun's high-density core shifts relative to the solar surface as gravitational forces exerted by the major planets cause the Sun to experience abrupt acceleration and deceleration, like a yoyo on a string, in its orbit about the ever-changing centre-of-mass of the solar system. Solar cycles (surface magnetic activity, solar eruptions, and sunspots) and major climate changes arise from changes in the depth of the energetic SN co...

  1. Asymmetric Explosions of Thermonuclear Supernovae

    CERN Document Server

    Ghezzi, C R; Horváth, J E

    2004-01-01

    A type Ia supernova explosion starts in a white dwarf as a laminar deflagration at the center of the star and soon several hydrodynamic instabilities (in particular, the Rayleigh-Taylor (R-T) instability) begin to act. In previous work (Ghezzi, de Gouveia Dal Pino, & Horvath 2001), we addressed the propagation of an initially laminar thermonuclear flame in presence of a magnetic field assumed to be dipolar. We were able to show that, within the framework of a fractal model for the flame velocity, the front is affected by the field through the quenching of the R-T instability growth in the direction perpendicular to the field lines. As a consequence, an asymmetry develops between the magnetic polar and the equatorial axis that gives a prolate shape to the burning front. We have here computed numerically the total integrated asymmetry as the flame front propagates outward through the expanding shells of decreasing density of the magnetized white dwarf progenitor, for several chemical compositions, and found...

  2. Short-term effects of supernova explosions on radiocarbon production

    Energy Technology Data Exchange (ETDEWEB)

    Povinec, P. (Komenskeho Univ., Bratislava (Czechoslovakia). Prirodovedecka Fakulta)

    1980-01-01

    The short-term increase in cosmic ray intensity caused by a supernova gamma-ray burst as well as the long-term increase resulting from corpuscular particles accelerated during the supernova explosion may be investigated by cosmogenic radiocarbon. It is shown that o.alactic supernovae exploding at distances up to 1 kpc from the Earth could cause a measurable increase in radiocarbon concentration in the past. Radiocarbon measurements for the period of the Tycho de Brahe supernova showed negative results.

  3. Progress in multi-waveband observations of supernova remnants

    Institute of Scientific and Technical Information of China (English)

    Xuejuan Yang; Fangjun Lu; Wenwu Tian

    2008-01-01

    The development of observational techniques has enriched our knowledge of supernova remnants.In this paper,we review the main progresses in the last decade,including new discoveries of supernova remnants and the associated(rare type of pulsars,nucleosynthesis,the interaction between supernova remnants and molecular clouds,dust in the supernova remnants,shock physics,and cosmic ray accelerations.

  4. GALACTIC AND EXTRAGALACTIC SUPERNOVA REMNANTS AS SITES OF PARTICLE ACCELERATION

    Directory of Open Access Journals (Sweden)

    Manami Sasaki

    2013-12-01

    Full Text Available Supernova remnants, owing to their strong shock waves, are likely sources of Galactic cosmic rays. Studies of supernova remnants in X-rays and gamma rays provide us with new insights into the acceleration of particles to high energies. This paper reviews the basic physics of supernova remnant shocks and associated particle acceleration and radiation processes. In addition, the study of supernova remnant populations in nearby galaxies and the implications for Galactic cosmic ray distribution are discussed.

  5. Superluminous Supernovae: No Threat from Eta Carinae

    Science.gov (United States)

    Thomas, Brian; Melott, A. L.; Fields, B. D.; Anthony-Twarog, B. J.

    2008-05-01

    Recently Supernova 2006gy was noted as the most luminous ever recorded, with a total radiated energy of 1044 Joules. It was proposed that the progenitor may have been a massive evolved star similar to η Carinae, which resides in our own galaxy at a distance of about 2.3 kpc. η Carinae appears ready to detonate. Although it is too distant to pose a serious threat as a normal supernova, and given its rotation axis is unlikely to produce a Gamma-Ray Burst oriented toward the Earth, η Carinae is about 30,000 times nearer than 2006gy, and we re-evaluate it as a potential superluminous supernova. We find that given the large ratio of emission in the optical to the X-ray, atmospheric effects are negligible. Ionization of the atmosphere and concomitant ozone depletion are unlikely to be important. Any cosmic ray effects should be spread out over 104 y, and similarly unlikely to produce any serious perturbation to the biosphere. We also discuss a new possible effect of supernovae, endocrine disruption induced by blue light near the peak of the optical spectrum. This is a possibility for nearby supernovae at distances too large to be considered "dangerous” for other reasons. However, due to reddening and extinction by the interstellar medium, η Carinae is unlikely to trigger such effects to any significant degree.

  6. Snapping Supernovae at z>1.7

    Energy Technology Data Exchange (ETDEWEB)

    Aldering, Greg; Kim, Alex G.; Kowalski, Marek; Linder, Eric V.; Perlmutter, Saul

    2006-07-03

    We examine the utility of very high redshift Type Ia supernovae for cosmology and systematic uncertainty control. Next generation space surveys such as the Supernova/Acceleration Probe (SNAP) will obtain thousands of supernovae at z>1.7, beyond the design redshift for which the supernovae will be exquisitely characterized. We find that any z gtrsim 2 standard candles' use for cosmological parameter estimation is quite modest and subject to pitfalls; we examine gravitational lensing, redshift calibration, and contamination effects in some detail. The very high redshift supernovae - both thermonuclear and core collapse - will provide copious interesting information on star formation, environment, and evolution. However, the new observational systematics that must be faced, as well as the limited expansion of SN-parameter space afforded, does not point to high value for 1.7

  7. 97-ERD-022 final report: Supernova on Nova

    Energy Technology Data Exchange (ETDEWEB)

    Remington, B A

    1999-03-11

    This is the final year of the 3-year LDRD-ERD involving Lasers, D&NT, Physics, and ILSA to develope astrophysics experiments on intense lasers such as the Nova and Gekko lasers. During this 3 year period, we have developed a highly successful experiment probing the hydrodynamics of the explosion phase of core-collapse supernovae, which occurs during the first ~3 hours after core collapse. This was in collaboration with the Univ. of Arizona and CEA/Saclay. We also developed a very successful experiment to probe the hydrodynamics of the later time, young remnant phase, meaning the first ~10-20 years after core collapse. This was in collaboration with the Univ. of Michigan and Univ. of Colorado. Finally, we developed during the final year an exquisite experiment to probe the dynamics of radiative, high Mach number astrophysical jets, in collaboration with the Univ. of Maryland and Osaka Univ. Each experiment has received very high visibility, with a multitude of publications, both in the technical journals (most importantly, the astrophysical journals) and in the popular press. The attached publication list shows 25 papers published or submitted to technical journals, 5 articles appearing in the popular press (including a cover story of Sky and Telescope), and 65 conference presentations, ~10 of which were invited talks. The most important papers to come out of this effort was a comprehensive theory paper for Ap. J. establishing the rigorous scaling between laboratory laser experiments and the astrophysical subjects of interest: supernovae, supernova remnants, and jets; and a review article for Science covering this emerging subfield of Astrophysics on Intense Lasers. Since there are so many publications that have resulted from this LDRD project, only these two most important papers are attached. The rest are properly referenced, and can be found online or in the library. In anticipation of the closing of the Nova laser, we have successfully proposed transferring the

  8. A solar-type star polluted by calcium-rich supernova ejecta inside the supernova remnant RCW 86

    Science.gov (United States)

    Gvaramadze, Vasilii V.; Langer, Norbert; Fossati, Luca; Bock, Douglas C.-J.; Castro, Norberto; Georgiev, Iskren Y.; Greiner, Jochen; Johnston, Simon; Rau, Arne; Tauris, Thomas M.

    2017-06-01

    When a massive star in a binary system explodes as a supernova, its companion star may be polluted with heavy elements from the supernova ejecta. Such pollution has been detected in a handful of post-supernova binaries 1 , but none of them is associated with a supernova remnant. We report the discovery of a binary G star strongly polluted with calcium and other elements at the position of the candidate neutron star [GV2003] N within the young galactic supernova remnant RCW 86. Our discovery suggests that the progenitor of the supernova that produced RCW 86 could have been a moving star, which exploded near the edge of its wind bubble and lost most of its initial mass because of common-envelope evolution shortly before core collapse, and that the supernova explosion might belong to the class of calcium-rich supernovae — faint and fast transients 2,3 , the origin of which is strongly debated 4-6 .

  9. Investigations of supernovae and supernova remnants in the era of SKA

    CERN Document Server

    Wang, Lingzhi; Zhu, Hui; Tian, Wenwu; Wang, Xiaofeng

    2015-01-01

    Two main physical mechanisms are used to explain supernova explosions: thermonuclear explosion of a white dwarf(Type Ia) and core collapse of a massive star (Type II and Type Ib/Ic). Type Ia supernovae serve as distance indicators that led to the discovery of the accelerating expansion of the Universe. The exact nature of their progenitor systems however remain unclear. Radio emission from the interaction between the explosion shock front and its surrounding CSM or ISM provides an important probe into the progenitor star's last evolutionary stage. No radio emission has yet been detected from Type Ia supernovae by current telescopes. The SKA will hopefully detect radio emission from Type Ia supernovae due to its much better sensitivity and resolution. There is a 'supernovae rate problem' for the core collapse supernovae because the optically dim ones are missed due to being intrinsically faint and/or due to dust obscuration. A number of dust-enshrouded optically hidden supernovae should be discovered via SKA1-...

  10. Supernova remnants, pulsar wind nebulae and their interaction

    NARCIS (Netherlands)

    Swaluw, E. van der

    2001-01-01

    A supernova explosion marks the end of the evolution of a massive star. What remains of the exploded star is a high density neutron star or a black hole. The material which has been ejected by the supernova explosion will manifest itself as a supernova remnant: a hot bubble of gas expanding in the

  11. The destruction of cosmological minihalos by primordial supernovae

    NARCIS (Netherlands)

    Whalen, D.; van Veelen, B.; O'Shea, B.W.; Norman, M.L.

    2008-01-01

    We present numerical simulations of primordial supernovae in cosmological minihalos at z ~ 20. We consider Type II supernovae, hypernovae, and pair instability supernovae (PISN) in halos from 6.9 × 105 to 1.2 × 107 M, those in which Population III stars are expected to form via H2 cooling. Our simul

  12. Standardizing Type Ia supernovae using Near Infrared rebrightening time

    CERN Document Server

    Shariff, Hikmatali; Jiao, Xiyun; Leibundgut, Bruno; Trotta, Roberto; van Dyk, David A

    2016-01-01

    Accurate standardisation of Type Ia supernovae (SNIa) is instrumental to the usage of SNIa as distance indicators. We analyse a homogeneous sample of 22 low-z SNIa, observed by the Carnegie Supernova Project (CSP) in the optical and near infra-red (NIR). We study the time of the second peak in the NIR band due to re-brightening, t2, as an alternative standardisation parameter of SNIa peak brightness. We use BAHAMAS, a Bayesian hierarchical model for SNIa cosmology, to determine the residual scatter in the Hubble diagram. We find that in the absence of a colour correction, t2 is a better standardisation parameter compared to stretch: t2 has a 1 sigma posterior interval for the Hubble residual scatter of [0.250, 0.257] , compared to [0.280, 0.287] when stretch (x1) alone is used. We demonstrate that when employed together with a colour correction, t2 and stretch lead to similar residual scatter. Using colour, stretch and t2 jointly as standardisation parameters does not result in any further reduction in scatte...

  13. Tests of Environmental Effects on Type Ia Supernova Production

    Science.gov (United States)

    Sadler, Suzanna M.; Strolger, L.; Wolff, S.

    2011-01-01

    The host galaxy environments of type Ia supernovae (SNe Ia) provide our best opportunity for constraining the mechanism(s) of the SN Ia progenitor system, i.e., the stars involved, the incubation times, and the sensitivity of SNe Ia to changes in the local gas-phase metallicity. The latter can affect the luminosity of the resultant event, and possibly the success in ultimately yielding a SN Ia. We seek to solidify possible environmental trends in SN Ia rates from direct measures of host galaxy properties, using the sample collected by the Nearby Galaxies Supernova Search project. This study will uncover which has the greatest influence on SN Ia production efficiency: parent population age, rate of star-formation, or metallicity. Here, we will show some preliminary results from SSP model fitting (of age and [Fe/H]) to a selection of hosts obtained thus far from this study. The complete sample will provide a validity test of the mostly indirect trends being established for SNe Ia from the LOSS, SDSS, SNfactory and other surveys, and may ultimately steer future investigations towards more precise SN Ia cosmology.

  14. CfA Nearby Supernova Ia Light Curves

    Science.gov (United States)

    Hicken, Malcolm; Berlind, P.; Blondin, S.; Calkins, M.; Challis, P.; Esquerdo, G.; Everett, M.; Fernandez, J.; Jha, S.; Kirshner, R. P.; Latham, D.; Modjaz, M.; Rest, A.; Wood-Vasey, M.

    2007-12-01

    Type Ia supernovae (SN Ia) are central in measuring the accelerated expansion of the Universe and the properties of the underlying dark energy. Nearby SN Ia are compared with distant ones to establish the history of cosmic expansion. In fact, current efforts in SN Ia cosmology are constrained by the limited number of well-observed nearby SN Ia. A significantly improved sample of nearby SN Ia, fully covering the space of Ia properties, is needed to maximize the utility of high-redshift SN Ia. Our ongoing project at the CfA has collected such a set of 170 SN Ia. We have used the FLWO 1.2m telescope. About half of our objects were observed in UBVRI with the 4Shooter camera and have an average of 10 epochs each while the other half was taken in UBVr'i' with the Keplercam instrument and have an average of 17 epochs each. We have now reduced this sample of over 25000 images and present calibrated light curves of these SN Ia along with an analysis of their properties. The CfA Supernova program is supported in part by the National Science Foundation through grant AST-0606772 to Harvard University.

  15. Long-rising Type II supernovae from PTF and CCCP

    CERN Document Server

    Taddia, F; Fremling, C; Migotto, K; Gal-Yam, A; Armen, S; Duggan, G; Ergon, M; Filippenko, A V; Fransson, C; Hosseinzadeh, G; Kasliwal, M M; Laher, R R; Leloudas, G; Leonard, D C; Lunnan, R; Masci, F J; Moon, D -S; Silverman, J M; Wozniak, P R

    2016-01-01

    Supernova (SN) 1987A was a peculiar H-rich event with a long-rising (LR) light curve (LC), stemming from a compact blue supergiant star (BSG). Only a few similar events have been presented in the literature. We present new data for a sample of 6 LR Type II SNe (SNe II), 3 of which were discovered and observed by the Palomar Transient Factory (PTF) and 3 observed by the Caltech Core-Collapse Project (CCCP). Our aim is to enlarge the family of LR SNe II, characterizing their properties. Spectra, LCs, and host-galaxies (HG) of these SNe are presented. Comparisons with known SN 1987A-like events are shown, with emphasis on the absolute magnitudes, colors, expansion velocities, and HG metallicities. Bolometric properties are derived from the multiband LC. By modeling the early-time LCs with scaling relations derived from the SuperNova Explosion Code (SNEC) models of MESA progenitor stars, we estimate the progenitor radii of these SNe and other progenitor parameters. We present PTF12kso, a LR SN II with the largest...

  16. Electron capture in carbon dwarf supernovae

    Science.gov (United States)

    Mazurek, T. J.; Truran, J. W.; Cameron, A. G. W.

    1974-01-01

    The rates of electron capture on heavier elements under the extreme conditions predicted for dwarf star supernovae have been computed, incorporating modifications that seem to be indicated by present experimental results. An estimate of the maximum possible value of such rates is also given. The distribution of nuclei in nuclear statistical equilibrium has been calculated for the range of expected supernovae conditions, including the effects of the temperature dependence of nuclear partition functions. These nuclide abundance distributions are then used to compute nuclear equilibrium thermodynamic properties. The effects of the electron capture on such equilibrium matter are discussed. In the context of the 'carbon detonation' supernova model, the dwarf central density required to ensure core collapse to a neutron star configuration is found to be slightly higher than that obtained by Bruenn (1972) with the electron capture rates of Hansen (1966).-

  17. Supernova Recognition using Support Vector Machines

    Energy Technology Data Exchange (ETDEWEB)

    Romano, Raquel A.; Aragon, Cecilia R.; Ding, Chris

    2006-10-01

    We introduce a novel application of Support Vector Machines(SVMs) to the problem of identifying potential supernovae usingphotometric and geometric features computed from astronomical imagery.The challenges of this supervised learning application are significant:1) noisy and corrupt imagery resulting in high levels of featureuncertainty,2) features with heavy-tailed, peaked distributions,3)extremely imbalanced and overlapping positiveand negative data sets, and4) the need to reach high positive classification rates, i.e. to find allpotential supernovae, while reducing the burdensome workload of manuallyexamining false positives. High accuracy is achieved viaasign-preserving, shifted log transform applied to features with peaked,heavy-tailed distributions. The imbalanced data problem is handled byoversampling positive examples,selectively sampling misclassifiednegative examples,and iteratively training multiple SVMs for improvedsupernovarecognition on unseen test data. We present crossvalidationresults and demonstrate the impact on a largescale supernova survey thatcurrently uses the SVM decision value to rank-order 600,000 potentialsupernovae each night.

  18. Probing Exotic Physics With Supernova Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Kelso, Chris; Hooper, Dan

    2010-09-01

    Future galactic supernovae will provide an extremely long baseline for studying the properties and interactions of neutrinos. In this paper, we discuss the possibility of using such an event to constrain (or discover) the effects of exotic physics in scenarios that are not currently constrained and are not accessible with reactor or solar neutrino experiments. In particular, we focus on the cases of neutrino decay and quantum decoherence. We calculate the expected signal from a core-collapse supernova in both current and future water Cerenkov, scintillating, and liquid argon detectors, and find that such observations will be capable of distinguishing between many of these scenarios. Additionally, future detectors will be capable of making strong, model-independent conclusions by examining events associated with a galactic supernova's neutronization burst.

  19. Supernova Neutrinos: Production, Oscillations and Detection

    CERN Document Server

    Mirizzi, Alessandro; Janka, Hans-Thomas; Saviano, Ninetta; Scholberg, Kate; Bollig, Robert; Hudepohl, Lorenz; Chakraborty, Sovan

    2015-01-01

    Neutrinos play a crucial role in the collapse and explosion of massive stars, governing the infall dynamics of the stellar core, triggering and fueling the explosion and driving the cooling and deleptonization of the newly formed neutron star. Due to their role neutrinos carry information from the heart of the explosion and, due to their weakly interacting nature, offer the only direct probe of the dynamics and thermodynamics at the center of a supernova. In this paper, we review the present status of modelling the neutrino physics and signal formation in collapsing and exploding stars. We assess the capability of current and planned large underground neutrino detectors to yield faithful information of the time and flavor dependent neutrino signal from a future Galactic supernova. We show how the observable neutrino burst would provide a benchmark for fundamental supernova physics with unprecedented richness of detail. Exploiting the treasure of the measured neutrino events requires a careful discrimination o...

  20. Supernova discoveries 2010: statistics and trends

    CERN Document Server

    Gal-Yam, Avishay

    2013-01-01

    We have inspected all supernova discoveries reported during 2010, a total of 538 events. This number includes a small number of "supernova impostors" (bright extragalactic eruptions) but not novae or events that turned out to be Galactic stars. We examine the statistics of all discovered objects, as well as those of the subset of spectroscopically-confirmed events. This year shows the rise of wide-field non-targeted supernova surveys to prominence, with the largest numbers of events contributed by the CRTS and PTF surveys (189 and 88 events respectively), followed by the integrated contribution of numerous amateurs (82 events). Among spectroscopically-confirmed events the PTF (88 events) leads, before amateur discoveries (69 events), closely followed by the CRTS and PS1 surveys (67 and 63 events, respectively). Traditional galaxy-targeted surveys such as LOSS and CHASE, maintain a strong contribution (50 and 36 events, respectively) with high spectroscopic completeness (96% for LOSS). It is interesting to not...

  1. Corrugated capillary as THz Cherenkov Smith-Purcell radiator

    Science.gov (United States)

    Lekomtsev, K. V.; Aryshev, A. S.; Tishchenko, A. A.; Ponomarenko, A. A.; Sukharev, V. M.; Terunuma, N.; Urakawa, J.; Strikhanov, M. N.

    2016-07-01

    In this article we discussed Particle In Cell electromagnetic simulations and mechanical design of dielectric capillaries that produce THz Cherenkov Smith-Purcell radiation (ChSPR), arising when a femtosecond electron multi-bunch beam propagates through corrugated and non-corrugated dielectric capillaries with metallic radiation reflectors. We investigated the influence of the four-bunch beam on the SPR field spectrum and on the ChSPR power spectrum, and the influence of the non-central beam propagation on the ChSPR power spectrum. We also discussed the design and assembly of the capillaries, constructed as sets of cylindrical rings.

  2. Characteristics of Smith-Purcell radiation in millimeter wavelength region

    Science.gov (United States)

    Naumenko, G. A.; Potylitsyn, A. P.; Karataev, P.; Bleko, V.; Sukhikh, L. G.; Shevelev, M. V.; Popov, Yu

    2016-07-01

    Investigations of the Smith-Purcell radiation (SPR) were began with non-relativistic electron beams with some unexpected experimental results. Further the experimental investigations were performed with relativistic electron beams for application to beam diagnostics. Large discrepancy between different theoretical models significantly increases the role of experimental studies of this phenomenon. In this report we present some problems and features of experimental investigations of SPR in millimeter wavelength region. The problems of prewave zone and coherent effects are considered. The shadowing effect, focusing of radiation using a parabolic SPR target and effect of inclination of target strips were investigated with moderately relativistic electron beam.

  3. [Smith-Magenis syndrome: case report and review].

    Science.gov (United States)

    Bronberg, Rubén; Ziembar, María; Drut, Mónica; Goldschmidt, Ernesto

    2008-04-01

    Smith-Magenis syndrome (SMS) is characterized by distinctive facial features that progress with age, developmental delay, cognitive impairment, and behavioral abnormalities associated with molecular anomaly in 17p11.2. Treatment includes: early childhood intervention programs, special education, vocational training later in life, and speech/language, physical, and occupational, behavioral, and sensory integration therapies. We report a 14-year-old girl with mental retardation, behavioral abnormalities and facial dysmorphism, with SMS diagnosis confirmed by cytogenetic analysis and in situ hydridization (FISH).

  4. Rediscovery of the Rare Sea Snake Hydrophis parviceps Smith 1935

    DEFF Research Database (Denmark)

    Rasmussen, Arne R.; Elmberg, Johan; Sanders, Kate L.

    2012-01-01

    Smith's small-headed sea snake, Hydrophis parviceps, was originally described in 1935 from a single type specimen collected in southern Vietnam. Since this time there has been only one further record for the species-a specimen collected near the type locality in 1960 that has since been lost....... Through field surveys in southern Vietnam in 2001, we obtained three additional specimens of this poorly known sea snake from fisheries bycatch. In the current paper, we present morphological and molecular data for the three new specimens and the holotype, and redescribe H. parviceps based on data...

  5. The Smith normal form of product distance matrices

    Directory of Open Access Journals (Sweden)

    Bapat R. B.

    2016-01-01

    Full Text Available Let G = (V, E be a connected graph with 2-connected blocks H1, H2, . . . , Hr. Motivated by the exponential distance matrix, Bapat and Sivasubramanian in [4] defined its product distance matrix DG and showed that det DG only depends on det DHi for 1 ≤ i ≤ r and not on the manner in which its blocks are connected. In this work, when distances are symmetric, we generalize this result to the Smith Normal Form of DG and give an explicit formula for the invariant factors of DG.

  6. 传奇酿酒师Charles Smith

    Institute of Scientific and Technical Information of China (English)

    Lok Chan

    2010-01-01

    @@ 接下来要介绍的是来自WALLA WALLA的另一个庄园主兼酿酒师:疯狂的Charles Smith. 可能读者们会觉得笔者用了疯狂来形容一位远道而来的庄园主不够尊重,但请大家相信笔者,绝对没有不敬的意思.不信?那大家就来认识一下这位疯狂的庄主吧!

  7. No information or horizon paradoxes for Th. Smiths

    CERN Document Server

    Maes, Christian

    2015-01-01

    'Th'e 'S'tatistical 'm'echanician 'i'n 'th'e 's'treet (our Th. Smiths) must be surprised upon hearing popular versions of some of today's most discussed paradoxes in astronomy and cosmology. In fact, rather standard reminders of the meaning of thermal probabilities in statistical mechanics appear to answer the horizon problem (one of the major motivations for inflation theory) and the information paradox (related to black hole physics), at least as they are usually presented. Still the paradoxes point to interesting gaps in our statistical understanding of (quantum) gravitational effects.

  8. Adam Smith y Sistemas Dinámicos

    OpenAIRE

    Acuña, Osvaldo; Ulate, Fernán

    2008-01-01

    Presentamos un sistema dinámico sencillo con dos ecuaciones diferenciales, una representa la trayectoria del precio y la otra la de la cantidad de un bien en una economía. Nuestro modelo se basa sobre todo en la teoría clásica de precios expuesta por Adam Smith en La Riqueza de las Naciones. Al final del trabajo, se presenta, a modo de ejemplo, un estudio para el caso del ganado vacuno en la economía mundial.

  9. New Constraints on $\\Omega_M$, $\\Omega_\\Lambda$, and w from an Independent Set of Eleven High-Redshift Supernovae Observed with HST

    CERN Document Server

    Knop, R A; Amanullah, R; Astier, Pierre; Blanc, G; Burns, M S; Conley, A; Deustua, S E; Doi, M; Ellis, R; Fabbro, S; Folatelli, G; Fruchter, A S; Garavini, G; Garmond, S; Garton, K; Gibbons, R; Goldhaber, G; Goobar, A; Groom, D E; Hardin, D; Hook, I; Howell, D A; Kim, A G; Lee Byung Cheol; Lidman, C E; Méndez, J; Nobili, S; Nugent, P; Pain, R; Panagia, N; Pennypacker, C R; Perlmutter, S; Quimby, R; Raux, J; Regnault, N; Ruiz-Lapuente, P; Sainton, G; Schaefer, B; Schahmaneche, K; Smith, E; Spadafora, A L; Stanishev, V; Sullivan, M; Walton, N A; Wang, L; Wood-Vasey, W M; Yasuda, N

    2003-01-01

    We report measurements of $\\Omega_M$, $\\Omega_\\Lambda$, and w from eleven supernovae at z=0.36-0.86 with high-quality lightcurves measured using WFPC-2 on the HST. This is an independent set of high-redshift supernovae that confirms previous supernova evidence for an accelerating Universe. Combined with earlier Supernova Cosmology Project data, the new supernovae yield a flat-universe measurement of the mass density $\\Omega_M=0.25^{+0.07}_{-0.06}$ (statistical) $\\pm0.04$ (identified systematics), or equivalently, a cosmological constant of $\\Omega_\\Lambda=0.75^{+0.06}_{-0.07}$ (statistical) $\\pm0.04$ (identified systematics). When the supernova results are combined with independent flat-universe measurements of $\\Omega_M$ from CMB and galaxy redshift distortion data, they provide a measurement of $w=-1.05^{+0.15}_{-0.20}$ (statistical) $\\pm0.09$ (identified systematic), if w is assumed to be constant in time. The new data offer greatly improved color measurements of the high-redshift supernovae, and hence imp...

  10. Deep Recurrent Neural Networks for Supernovae Classification

    Science.gov (United States)

    Charnock, Tom; Moss, Adam

    2017-03-01

    We apply deep recurrent neural networks, which are capable of learning complex sequential information, to classify supernovae (code available at https://github.com/adammoss/supernovae). The observational time and filter fluxes are used as inputs to the network, but since the inputs are agnostic, additional data such as host galaxy information can also be included. Using the Supernovae Photometric Classification Challenge (SPCC) data, we find that deep networks are capable of learning about light curves, however the performance of the network is highly sensitive to the amount of training data. For a training size of 50% of the representational SPCC data set (around 104 supernovae) we obtain a type-Ia versus non-type-Ia classification accuracy of 94.7%, an area under the Receiver Operating Characteristic curve AUC of 0.986 and an SPCC figure-of-merit F 1 = 0.64. When using only the data for the early-epoch challenge defined by the SPCC, we achieve a classification accuracy of 93.1%, AUC of 0.977, and F 1 = 0.58, results almost as good as with the whole light curve. By employing bidirectional neural networks, we can acquire impressive classification results between supernovae types I, II and III at an accuracy of 90.4% and AUC of 0.974. We also apply a pre-trained model to obtain classification probabilities as a function of time and show that it can give early indications of supernovae type. Our method is competitive with existing algorithms and has applications for future large-scale photometric surveys.

  11. Berkeley Lab's Saul Perlmutter wins E.O. Lawrence Award scientist's work on supernovae reveals accelerating universe

    CERN Multimedia

    2002-01-01

    "Saul Perlmutter, a member of Lawrence Berkeley National Laboratory's Physics Division and leader of the international Supernova Cosmology Project based there, has won the Department of Energy's 2002 E.O. Lawrence Award in the physics category" (1/2 page).

  12. Collective Oscillations and Diffuse Supernova Neutrino Background

    Science.gov (United States)

    Kar, Kamales; Chakraborty, Sovan; Choubey, Sandhya

    2012-01-01

    Core-collapse supernova explosions give rise to the emission of a huge flux of neutrinos of all flavors. In this article we describe the phenomenon neutrino-neutrino interaction of these weakly interacting particles at the very high density central region of the stellar core giving rise to non-linear collective oscillations in both the neutrino and antineutrino sectors. The effect of the collective oscillations on the Diffuse Supernova Neutrino Background is elaborated with emphasis on its future detection and the connection of that to neutrino mass hierarchy.

  13. Absolute-Magnitude Distributions of Supernovae

    CERN Document Server

    Richardson, Dean; Wright, John; Maddox, Larry

    2014-01-01

    The absolute-magnitude distributions of seven supernova types are presented. The data used here were primarily taken from the Asiago Supernova Catalogue, but were supplemented with additional data. We accounted for both foreground and host-galaxy extinction. A bootstrap method is used to correct the samples for Malmquist bias. Separately, we generate volume-limited samples, restricted to events within 100 Mpc. We find that the superluminous events (M_B -15) make up about 3%. The normal Ia distribution was the brightest with a mean absolute blue magnitude of -19.25. The IIP distribution was the dimmest at -16.75.

  14. Formation of Nuclear "Pasta" in Supernovae

    CERN Document Server

    Watanabe, Gentaro; Maruyama, Toshiki; Sato, Katsuhiko; Yasuoka, Kenji; Ebisuzaki, Toshikazu

    2009-01-01

    In supernova cores, nuclear "pasta" phases such as triangular lattice of rod-like nuclei and layered structure of slab-like nuclei are considered to exist. However, it is still unclear whether or not they are actually formed in collapsing supernova cores. Using {\\it ab-initio} numerical simulations called the Quantum Molecular Dynamics (QMD), we here solve this problem by demonstrating that a lattice of rod-like nuclei is formed from a bcc lattice by compression. We also find that, in the transition process, the system undergoes zigzag configuration of elongated nuclei, which are formed by a fusion of two original spherical nuclei.

  15. Deflagrations and Detonations in Thermonuclear Supernovae

    CERN Document Server

    Gamezo, V N; Oran, E S; Gamezo, Vadim N.; Khokhlov, Alexei M.; Oran, Elaine S.

    2004-01-01

    We study a type Ia supernova explosion using three-dimensional numerical simulations based on reactive fluid dynamics. We consider a delayed-detonation model that assumes a deflagration-to-detonation transition. In contrast to the pure deflagration model, the delayed-detonation model releases enough energy to account for a healthy explosion, and does not leave carbon, oxygen, and intermediate-mass elements in central parts of a white dwarf. This removes the key disagreement between simulations and observations, and makes a delayed detonation the mostly likely mechanism for type Ia supernovae.

  16. Search for supernova produced {sup 60}Fe in Earth's microfossil record

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Peter; Bishop, Shawn; Chernenko, Valentyna; Faestermann, Thomas; Fimiani, Leticia; Gomez, Jose; Hain, Karin; Korschinek, Gunther [Technische Univ. Muenchen, Garching (Germany). Physik-Department; Egli, Ramon [Central Institute for Meteorology and Geodynamics, Vienna (Austria)

    2013-07-01

    The detection of supernova debris on Earth can be achieved by use of accelerator mass spectrometry (AMS) to search for radionuclides like {sup 60}Fe. This long-lived isotope (T{sub 1/2}=2.6 Myr) is produced in massive stars and is expected to be present in the debris of type II supernovae. The discovery of {sup 60}Fe in a ferromanganese crust from the Pacific ocean (Knie et al., 2004) was interpreted as the input of a supernova explosion about 2.2 Myr ago. Currently, several projects are aiming for the confirmation of the signature of {sup 60}Fe in terrestrial and lunar samples. In this talk, the search for this {sup 60}Fe signature in Earth's microfossil record is presented. The sample material for this study is marine sediment from the eastern equatorial Pacific. A specific kind of secondary (formed in situ) magnetite mineral contained in the sample material are magnetofossils, which are the remains of magnetotactic bacteria, which are the target for extraction. The chemical extraction technique used to produce AMS samples has been characterized using newly developed magnetic analysis methods and has been shown to be extremely selective towards secondary magnetite. The AMS samples produced in this way are uniquely suited for the search for supernova {sup 60}Fe. Preliminary AMS results are presented.

  17. 3D simulations of young core-collapse supernova remnants undergoing efficient particle acceleration

    CERN Document Server

    Ferrand, Gilles

    2016-01-01

    Within our Galaxy, supernova remnants are believed to be the major sources of cosmic rays up to the "knee". However important questions remain regarding the share of the hadronic and leptonic components, and the fraction of the supernova energy channelled into these components. We address such question by the means of numerical simulations that combine a hydrodynamic treatment of the shock wave with a kinetic treatment of particle acceleration. Performing 3D simulations allows us to produce synthetic projected maps and spectra of the thermal and non-thermal emission, that can be compared with multi-wavelength observations (in radio, X-rays, and gamma-rays). Supernovae come in different types, and although their energy budget is of the same order, their remnants have different properties, and so may contribute in different ways to the pool of Galactic cosmic-rays. Our first simulations were focused on thermonuclear supernovae, like Tycho's SNR, that usually occur in a mostly undisturbed medium. Here we present...

  18. Reducing Zero-point Systematics in Dark Energy Supernova Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Faccioli, Lorenzo; Kim, Alex G; Miquel, Ramon; Bernstein, Gary; Bonissent, Alain; Brown, Matthew; Carithers, William; Christiansen, Jodi; Connolly, Natalia; Deustua, Susana; Gerdes, David; Gladney, Larry; Kushner, Gary; Linder, Eric; McKee, Shawn; Mostek, Nick; Shukla, Hemant; Stebbins, Albert; Stoughton, Chris; Tucker, David

    2011-04-01

    We study the effect of filter zero-point uncertainties on future supernova dark energy missions. Fitting for calibration parameters using simultaneous analysis of all Type Ia supernova standard candles achieves a significant improvement over more traditional fit methods. This conclusion is robust under diverse experimental configurations (number of observed supernovae, maximum survey redshift, inclusion of additional systematics). This approach to supernova fitting considerably eases otherwise stringent mission cali- bration requirements. As an example we simulate a space-based mission based on the proposed JDEM satellite; however the method and conclusions are general and valid for any future supernova dark energy mission, ground or space-based.

  19. Hume, Smith e as etapas da sociedade comercial

    Directory of Open Access Journals (Sweden)

    Rogério Arthmar

    Full Text Available Resumo O artigo trata das concepções de David Hume e de Adam Smith sobre o ressurgimento da sociedade comercial na Europa após o feudalismo. Parte-se de breve exposição dos princípios filosóficos de Hume a fim de se apresentar suas teses referentes ao assunto na obra History of England. Mostra-se como ele associa o movimento parlamentar pela liberdade na Inglaterra com o progresso do comércio ocasionado pelo consumo de luxo da nobreza. Posteriormente, revisa-se a posição de Smith sobre os obstáculos à riqueza, bem como sua explicação para a decadência das civilizações grega e romana. Evidencia-se ainda como a interpretação smithiana do advento da sociedade comercial moderna apoia-se na versão antecipada por Hume. Por fim, destacam-se as implicações do conflito central entre predação e produção presente nas teorias do desenvolvimento de longo prazo da humanidade elaboradas por ambos os autores.

  20. The futility of utility: how market dynamics marginalize Adam Smith

    Science.gov (United States)

    McCauley, Joseph L.

    2000-10-01

    Economic theorizing is based on the postulated, nonempiric notion of utility. Economists assume that prices, dynamics, and market equilibria are supposed to be derived from utility. The results are supposed to represent mathematically the stabilizing action of Adam Smith's invisible hand. In deterministic excess demand dynamics I show the following. A utility function generally does not exist mathematically due to nonintegrable dynamics when production/investment are accounted for, resolving Mirowski's thesis. Price as a function of demand does not exist mathematically either. All equilibria are unstable. I then explain how deterministic chaos can be distinguished from random noise at short times. In the generalization to liquid markets and finance theory described by stochastic excess demand dynamics, I also show the following. Market price distributions cannot be rescaled to describe price movements as ‘equilibrium’ fluctuations about a systematic drift in price. Utility maximization does not describe equilibrium. Maximization of the Gibbs entropy of the observed price distribution of an asset would describe equilibrium, if equilibrium could be achieved, but equilibrium does not describe real, liquid markets (stocks, bonds, foreign exchange). There are three inconsistent definitions of equilibrium used in economics and finance, only one of which is correct. Prices in unregulated free markets are unstable against both noise and rising or falling expectations: Adam Smith's stabilizing invisible hand does not exist, either in mathematical models of liquid market data, or in real market data.

  1. Type Ia supernova rate studies from the SDSS-II Supernova Study

    Energy Technology Data Exchange (ETDEWEB)

    Dilday, Benjamin [Univ. of Chicago, IL (United States)

    2008-08-01

    The author presents new measurements of the type Ia SN rate from the SDSS-II Supernova Survey. The SDSS-II Supernova Survey was carried out during the Fall months (Sept.-Nov.) of 2005-2007 and discovered ~ 500 spectroscopically confirmed SNe Ia with densely sampled (once every ~ 4 days), multi-color light curves. Additionally, the SDSS-II Supernova Survey has discovered several hundred SNe Ia candidates with well-measured light curves, but without spectroscopic confirmation of type. This total, achieved in 9 months of observing, represents ~ 15-20% of the total SNe Ia discovered worldwide since 1885. The author describes some technical details of the SN Survey observations and SN search algorithms that contributed to the extremely high-yield of discovered SNe and that are important as context for the SDSS-II Supernova Survey SN Ia rate measurements.

  2. SALT2: using distant supernovae to improve the use of Type Ia supernovae as distance indicators

    CERN Document Server

    Guy, J; Baumont, S; Hardin, D; Pain, R; Regnault, N; Basa, S; Carlberg, R G; Conley, A; Fabbro, S; Fouchez, D; Hook, I M; Howell, D A; Perrett, K; Pritchet, C J; Rich, J; Sullivan, M; Antilogus, P; Aubourg, E; Bazin, G; Bronder, J; Filiol, M; Palanque-Delabrouille, Nathalie; Ripoche, P; Ruhlmann-Kleider, V

    2007-01-01

    We present an empirical model of Type Ia supernovae spectro-photometric evolution with time. The model is built using a large data set including light-curves and spectra of both nearby and distant supernovae, the latter being observed by the SNLS collaboration. We derive the average spectral sequence of Type Ia supernovae and their main variability components including a color variation law. The model allows us to measure distance moduli in the spectral range 2500-8000 A with calculable uncertainties, including those arising from variability of spectral features. Thanks to the use of high-redshift SNe to model the rest-frame UV spectral energy distribution, we are able to derive improved distance estimates for SNe Ia in the redshift range 0.8supernovae.

  3. Investigating the Nature of Dark Energy using Type Ia Supernovae with WFIRST-AFTA Space Mission

    Science.gov (United States)

    Perlmutter, Saul

    Scientifically, the WFIRST supernova program is unique: it makes possible a dark energy measurement that no other space mission or ground-based project is addressing, a measurement that will set the standard in determining the expansion history of the universe continuously from low to high redshifts (0.1 reliable, due to limitations of time the analysis was clearly limited in depth on a number of issues. The objective of this proposal is to further develop this program. Technically this is the WFIRST measurement that arguably requires the most advanced project development, since it requires near-real-time analysis and follow-up with WFIRST, and since it is using the IFU spectrograph in the WFI package, the IFU being the WFIRST instrument that does not yet have a completely consistent set of specifications in the design iteration of the SDT report. In this proposal for the WFIRST Scientific Investigation Team, focused primarily on the supernova dark energy measurements, we address these crucial technical needs by bringing the larger supernova community's expertise on the science elements together with a smaller focused team that can produce the specific deliverables. Thus the objectives of this 5 year proposal are the following: 1. Development of scientific performance requirements for the study of Dark Energy using Type Ia supernovae 2. Design an observing strategy using the Wide Field Instrument (WFI) and the Integral Field Spectrometer Unit (IFU) 3. Development of science data analysis techniques and data analysis software 4. Development of ground and space calibration requirements and estimating realistic correlated errors, both statistical and systematic 5. Development of simulations and data challenges to validate the above 6. Development of complete plans in coordination with WFIRST project, for all aspects of science simulations, precursor observations, ground calibration, observational needs, data processing, anciliary data collection

  4. Medium Duty Electric Vehicle Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Mackie, Robin J. D. [Smith Electric Vehicles Corporation, Kansas City, MO (United States)

    2015-05-31

    The Smith Electric Vehicle Demonstration Project (SDP) was integral to the Smith business plan to establish a manufacturing base in the United States (US) and produce a portfolio of All Electric Vehicles (AEV’s) for the medium duty commercial truck market. Smith focused on the commercial depot based logistics market, as it represented the market that was most ready for the early adoption of AEV technology. The SDP enabled Smith to accelerate its introduction of vehicles and increase the size of its US supply chain to support early market adoption of AEV’s that were cost competitive, fully met the needs of a diverse set of end users and were compliant with Federal safety and emissions requirements. The SDP accelerated the development and production of various electric drive vehicle systems to substantially reduce petroleum consumption, reduce vehicular emissions of greenhouse gases (GHG), and increase US jobs.

  5. Echoes from Ancient supernovae in the Large Magellanic Cloud

    Energy Technology Data Exchange (ETDEWEB)

    Rest, A; Suntzeff, N B; Olsen, K; Prieto, J L; Smith, R C; Welch, D L; Becker, A; Bergmann, M; Clocchiatti, A; Cook, K; Garg, A; Huber, M; Miknaitis, G; Minniti, D; Nikolaev, S; Stubbs, C

    2005-06-15

    In principle, historical supernovae could still be visible as scattered-light echoes even centuries later [1, 2]. Searches for surface brightness variations using photographic plates have not recovered any echoes in the regions of historical Galactic supernovae [3]. Using differenced images, our SuperMACHO collaboration has discovered three faint new variable surface brightness complexes with high apparent proper motion pointing back to well-defined positions in the Large Magellanic Cloud (LMC). These correspond to three of the six smallest (and likely youngest) supernova remnants believed to be due to thermonuclear (Type Ia) supernovae [4]. A lower limit to the age of these remnants and echoes is 200 years given the lack of any reported LMC supernovae until 1987. The discovery of historical supernova echoes in the LMC suggests that similar echoes for Galactic supernovae such as Tycho, Kepler, Cas A, or SN1006 could be visible using standard image differencing techniques.

  6. The supernova-gamma-ray burst-jet connection.

    Science.gov (United States)

    Hjorth, Jens

    2013-06-13

    The observed association between supernovae and gamma-ray bursts represents a cornerstone in our understanding of the nature of gamma-ray bursts. The collapsar model provides a theoretical framework for this connection. A key element is the launch of a bipolar jet (seen as a gamma-ray burst). The resulting hot cocoon disrupts the star, whereas the (56)Ni produced gives rise to radioactive heating of the ejecta, seen as a supernova. In this discussion paper, I summarize the observational status of the supernova-gamma-ray burst connection in the context of the 'engine' picture of jet-driven supernovae and highlight SN 2012bz/GRB 120422A--with its luminous supernova but intermediate high-energy luminosity--as a possible transition object between low-luminosity and jet gamma-ray bursts. The jet channel for supernova explosions may provide new insights into supernova explosions in general.

  7. The ASAS-SN Bright Supernova Catalog $-$ II. 2015

    CERN Document Server

    Holoien, T W -S; Stanek, K Z; Kochanek, C S; Shappee, B J; Prieto, J L; Dong, Subo; Brimacombe, J; Bishop, D W; Basu, U; Beacom, J F; Bersier, D; Chen, Ping; Danilet, A B; Falco, E; Godoy-Rivera, D; Goss, N; Pojmanski, G; Simonian, G V; Skowron, D M; Thompson, Todd A; Woźniak, P R; Avíla, C G; Bock, G; Carballo, J -L G; Conseil, E; Contreras, C; Cruz, I; andújar, J M F; Guo, Zhen; Hsiao, E Y; Kiyota, S; Koff, R A; Krannich, G; Madore, B F; Marples, P; Masi, G; Morrell, N; Monard, L A G; Munoz-Mateos, J C; Nicholls, B; Nicolas, J; Wagner, R M; Wiethoff, W S

    2016-01-01

    This manuscript presents information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during 2015, its second full year of operations. The same information is presented for bright ($m_V\\leq17$), spectroscopically confirmed supernovae discovered by other sources in 2015. As with the first ASAS-SN bright supernova catalog, we also present redshifts and near-UV through IR magnitudes for all supernova host galaxies in both samples. Combined with our previous catalog, this work comprises a complete catalog of 455 supernovae from multiple professional and amateur sources, allowing for population studies that were previously impossible. This is the second of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team.

  8. The ASAS-SN Bright Supernova Catalog - II. 2015

    Science.gov (United States)

    Holoien, T. W.-S.; Brown, J. S.; Stanek, K. Z.; Kochanek, C. S.; Shappee, B. J.; Prieto, J. L.; Dong, Subo; Brimacombe, J.; Bishop, D. W.; Basu, U.; Beacom, J. F.; Bersier, D.; Chen, Ping; Danilet, A. B.; Falco, E.; Godoy-Rivera, D.; Goss, N.; Pojmanski, G.; Simonian, G. V.; Skowron, D. M.; Thompson, Todd A.; Woźniak, P. R.; Ávila, C. G.; Bock, G.; Carballo, J.-L. G.; Conseil, E.; Contreras, C.; Cruz, I.; Andújar, J. M. F.; Guo, Zhen; Hsiao, E. Y.; Kiyota, S.; Koff, R. A.; Krannich, G.; Madore, B. F.; Marples, P.; Masi, G.; Morrell, N.; Monard, L. A. G.; Munoz-Mateos, J. C.; Nicholls, B.; Nicolas, J.; Wagner, R. M.; Wiethoff, W. S.

    2017-01-01

    This manuscript presents information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during 2015, its second full year of operations. The same information is presented for bright (mV ≤ 17), spectroscopically confirmed supernovae discovered by other sources in 2015. As with the first ASAS-SN bright supernova catalog, we also present redshifts and near-UV through IR magnitudes for all supernova host galaxies in both samples. Combined with our previous catalog, this work comprises a complete catalog of 455 supernovae from multiple professional and amateur sources, allowing for population studies that were previously impossible. This is the second of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team.

  9. Supernova Feedback in Molecular Clouds: Global Evolution and Dynamics

    CERN Document Server

    Körtgen, Bastian; Banerjee, Robi; Vázquez-Semadeni, Enrique; Zamora-Avilés, Manuel

    2016-01-01

    We use magnetohydrodynamical simulations of converging warm neutral medium flows to analyse the formation and global evolution of magnetised and turbulent molecular clouds subject to supernova feedback from massive stars. We show that supernova feedback alone fails to disrupt entire, gravitationally bound, molecular clouds, but is able to disperse small--sized (~10 pc) regions on timescales of less than 1 Myr. Efficient radiative cooling of the supernova remnant as well as strong compression of the surrounding gas result in non-persistent energy and momentum input from the supernovae. However, if the time between subsequent supernovae is short and they are clustered, large hot bubbles form that disperse larger regions of the parental cloud. On longer timescales, supernova feedback increases the amount of gas with moderate temperatures (T~300-3000 K). Despite its inability to disrupt molecular clouds, supernova feedback leaves a strong imprint on the star formation process. We find an overall reduction of the ...

  10. X-ray studies of supernova remnants: A different view of supernova explosions

    OpenAIRE

    Badenes, Carles

    2010-01-01

    The unprecedented spatial and spectral resolutions of Chandra have revolutionized our view of the X-ray emission from supernova remnants. The excellent data sets accumulated on young, ejecta dominated objects like Cas A or Tycho present a unique opportunity to study at the same time the chemical and physical structure of the explosion debris and the characteristics of the circumstellar medium sculpted by the progenitor before the explosion. Supernova remnants can thus put strong constraints o...

  11. Research Performance Progress Report: Diverging Supernova Explosion Experiments on NIF

    Energy Technology Data Exchange (ETDEWEB)

    Plewa, Tomasz [Florida State Univ., Tallahassee, FL (United States)

    2016-10-25

    The aim of this project was to design a series of blast-wave driven Rayleigh-Taylor (RT) experiments on the National Ignition Facility (NIF). The experiments of this kind are relevant to mixing in core-collapse supernovae (ccSNe) and have the potential to address previously unanswered questions in high-energy density physics (HEDP) and astrophysics. The unmatched laser power of the NIF laser offers a unique chance to observe and study “new physics” like the mass extensions observed in HEDP RT experiments performed on the Omega laser [1], which might be linked to self-generated magnetic fields [2] and so far could not be reproduced by numerical simulations. Moreover, NIF is currently the only facility that offers the possibility to execute a diverging RT experiment, which would allow to observe processes such as inter-shell penetration via turbulent mixing and shock-proximity effects (distortion of the shock by RT spikes).

  12. Supernova 1987A: a Template to Link Supernovae to their Remnants

    CERN Document Server

    Orlando, S; Pumo, M L; Bocchino, F

    2015-01-01

    The emission of supernova remnants reflects the properties of both the progenitor supernovae and the surrounding environment. The complex morphology of the remnants, however, hampers the disentanglement of the two contributions. Here we aim at identifying the imprint of SN 1987A on the X-ray emission of its remnant and at constraining the structure of the environment surrounding the supernova. We performed high-resolution hydrodynamic simulations describing SN 1987A soon after the core-collapse and the following three-dimensional expansion of its remnant between days 1 and 15000 after the supernova. We demonstrated that the physical model reproducing the main observables of SN 1987A during the first 250 days of evolution reproduces also the X-ray emission of the subsequent expanding remnant, thus bridging the gap between supernovae and supernova remnants. By comparing model results with observations, we constrained the explosion energy in the range $1.2-1.4\\times 10^{51}$~erg and the envelope mass in the rang...

  13. The ultraviolet properties of supernovae

    Science.gov (United States)

    Brown, Peter J.

    2009-09-01

    Ultraviolet (UV) observations of supernovae (SNe) probe an important wavelength region where hot temperatures, extinction, and metallicity have strong effects. In addition, they provide a comparison set against which to compare and better understand rest frame UV observations of high redshift SNe observed in the optical. UV observations, however, are rare due to the need for telescopes above the atmosphere and the difficulty in observing transient objects with space based observatories. Limited observations with space based observatories, primarily the International Ultraviolet Explorer and the Hubble Space Telescope, are reviewed, after which the Ultra-Violet/Optical Telescope (UVOT) on the Swift spacecraft is introduced. With Swift we have observed more SNe than all previous UV missions combined. Case studies of two individual SNe are first presented: SNe 2005am and 2005cs. SN 2005am is the first young SN observed with Swift, and the near-UV (uvw1: central wavelength ~ 2600 λ) light curve is consistent with the previous "template" derived from IUE and HST observations of SNe 1990N and 1992A. SN 2005cs is the first plateau-type II (IIP) with a well observed UV light curve. UVOT observations show a dramatic drop in the UV brightness and shift in the spectral energy distribution from blue to red caused by the dropping temperature and resulting line blanketing in the UV. These case studies demonstrate the information available from the UV data for individual SNe. A photometry method for proper accounting of coincidence loss, aperture corrections, and subtraction of the underlying galaxy is detailed. This method is then applied to a large sample of SNe observed with UVOT. We present 25 light curves and compare SNe by type and across types. The SNe Ia, with a few exceptions, are shown to have very similar light curves in the near UV, whereas, the three SNe Ib/c we have observed are very different. The SNe IIP all have rapidly fading UV light curves, though with

  14. Probable Bright Supernova discovered by PSST

    Science.gov (United States)

    Smith, K. W.; Wright, D.; Smartt, S. J.; Young, D. R.; Huber, M.; Chambers, K. C.; Flewelling, H.; Willman, M.; Primak, N.; Schultz, A.; Gibson, B.; Magnier, E.; Waters, C.; Tonry, J.; Wainscoat, R. J.; Foley, R. J.; Jha, S. W.; Rest, A.; Scolnic, D.

    2016-09-01

    A bright transient, which is a probable supernova, has been discovered as part of the Pan-STARRS Survey for Transients (PSST). Information on all objects discovered by the Pan-STARRS Survey for Transients is available at http://star.pst.qub.ac.uk/ps1threepi/ (see Huber et al. ATel #7153).

  15. Explosions inside Ejecta and Most Luminous Supernovae

    CERN Document Server

    Blinnikov, S I

    2008-01-01

    The extremely luminous supernova SN2006gy is explained in the same way as other SNIIn events: light is produced by a radiative shock propagating in a dense circumstellar envelope formed by a previous weak explosion. The problems in the theory and observations of multiple-explosion SNe IIn are briefly reviewed.

  16. Did Egret Detect Distant Supernova Remnants?

    CERN Document Server

    Torres, D F; Dame, T M; Combi, J A; Butt, Y M; Torres, Diego F.; Romero, Gustavo E.; Dame, Thomas M.; Combi, Jorge A.; Butt, Yousaf M.

    2004-01-01

    It might be thought that supernova remnants (SNRs) more distant than a few kiloparsec from Earth could not have been detected by the EGRET experiment. This work analyzes the observational status of this statement in the light of new CO studies of SNRs.

  17. Multipole expansion method for supernova neutrino oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Huaiyu; Shalgar, Shashank, E-mail: duan@unm.edu, E-mail: shashankshalgar@unm.edu [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States)

    2014-10-01

    We demonstrate a multipole expansion method to calculate collective neutrino oscillations in supernovae using the neutrino bulb model. We show that it is much more efficient to solve multi-angle neutrino oscillations in multipole basis than in angle basis. The multipole expansion method also provides interesting insights into multi-angle calculations that were accomplished previously in angle basis.

  18. Ultraviolet diversity of Type Ia Supernovae

    DEFF Research Database (Denmark)

    Foley, Ryan J.; Pan, Yen-Chen; Brown, P.;

    2016-01-01

    Ultraviolet (UV) observations of Type Ia supernovae (SNe Ia) probe the outermost layers of the explosion, and UV spectra of SNe Ia are expected to be extremely sensitive to differences in progenitor composition and the details of the explosion. Here, we present the first study of a sample of high...

  19. First stars, hypernovae, and superluminous supernovae

    Science.gov (United States)

    Nomoto, Ken'Ichi

    2016-07-01

    After the big bang, production of heavy elements in the early universe takes place starting from the formation of the first (Pop III) stars, their evolution, and explosion. The Pop III supernova (SN) explosions have strong dynamical, thermal, and chemical feedback on the formation of subsequent stars and evolution of galaxies. However, the nature of Pop III stars/supernovae (SNe) have not been well-understood. The signature of nucleosynthesis yields of the first SN can be seen in the elemental abundance patterns observed in extremely metal-poor (EMP) stars. We show that the abundance patterns of EMP stars, e.g. the excess of C, Co, Zn relative to Fe, are in better agreement with the yields of hyper-energetic explosions (Hypernovae, (HNe)) rather than normal supernovae. We note the large variation of the abundance patterns of EMP stars propose that such a variation is related to the diversity of the GRB-SNe and posssibly superluminous supernovae (SLSNe). For example, the carbon-enhanced metal-poor (CEMP) stars may be related to the faint SNe (or dark HNe), which could be the explosions induced by relativistic jets. Finally, we examine the various mechanisms of SLSNe.

  20. Einstein Observations of Galactic supernova remnants

    Science.gov (United States)

    Seward, Frederick D.

    1990-01-01

    This paper summarizes the observations of Galactic supernova remnants with the imaging detectors of the Einstein Observatory. X-ray surface brightness contours of 47 remnants are shown together with gray-scale pictures. Count rates for these remnants have been derived and are listed for the HRI, IPC, and MPC detectors.

  1. Are Ti44-Producing Supernovae Exceptional?

    CERN Document Server

    The, L S; Diehl, R; Hartmann, D H; Iyudin, A F; Leising, M D; Meyer, B S; Motizuki, Y; Schönfelder, V

    2006-01-01

    According to standard models supernovae produce radioactive $^{44}$Ti, which should be visible in gamma-rays following decay to $^{44}$Ca for a few centuries. $^{44}Ti production is believed to be the source of cosmic $^{44}$Ca, whose abundance is well established. Yet, gamma-ray telescopes have not seen the expected young remnants of core collapse events. The $^{44}$Ti mean life of $\\tau \\simeq$ 89 y and the Galactic supernova rate of $\\simeq$ 3/100 y imply $\\simeq$ several detectable $^{44}Ti gamma-ray sources, but only one is clearly seen, the 340-year-old Cas A SNR. Furthermore, supernovae which produce much $^{44}Ti are expected to occur primarily in the inner part of the Galaxy, where young massive stars are most abundant. Because the Galaxy is transparent to gamma-rays, this should be the dominant location of expected gamma-ray sources. Yet the Cas A SNR as the only one source is located far from the inner Galaxy (at longitude 112 degree). We evaluate the surprising absence of detectable supernovae fro...

  2. Deep Recurrent Neural Networks for Supernovae Classification

    CERN Document Server

    Charnock, Tom

    2016-01-01

    We apply deep recurrent neural networks, which are capable of learning complex sequential information, to classify supernovae. The observational time and filter fluxes are used as inputs to the network, but since the inputs are agnostic additional data such as host galaxy information can also be included. Using the Supernovae Photometric Classification Challenge (SPCC) data, we find that deep networks are capable of learning about light curves, however the performance of the network is highly sensitive to the amount of training data. For a training size of 50% of the representational SPCC dataset (around 104 supernovae) we obtain a type Ia vs non type Ia classification accuracy of 94.8%, an area under the Receiver Operating Characteristic curve AUC of 0.986 and a SPCC figure-of-merit F1 = 0.64. We also apply a pre-trained model to obtain classification probabilities as a function of time, and show it can give early indications of supernovae type. Our method is competitive with existing algorithms and has appl...

  3. Essential ingredients in core-collapse supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Hix, W. Raphael [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States); Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Lentz, Eric J.; Chertkow, M. Austin; Harris, J. Austin [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Endeve, Eirik [Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6008 (United States); Baird, Mark [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6003 (United States); Messer, O. E. Bronson [Physics Division, Oak Ridge National Laboratory, Oak Ridge TN 37831-6354 (United States); Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Center for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge TN 37831-6008 (United States); Mezzacappa, Anthony [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200 (United States); Joint Institute for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6173 (United States); Bruenn, Stephen [Department of Physics, Florida Atlantic University, 777 W Glades Road, Boca Raton, FL 33431-0991 (United States); Blondin, John [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States)

    2014-04-15

    Carrying 10{sup 44} joules of kinetic energy and a rich mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up our solar system and ourselves. Signaling the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae combine physics over a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale) down to femtometer-scale nuclear reactions. We will discuss our emerging understanding of the convectively-unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have recently motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of the births of neutron stars and the supernovae that result. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  4. Supernovae and high density nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Kahana, S.

    1986-01-01

    The role of the nuclear equation of state (EOS) in producing prompt supernova explosions is examined. Results of calculations of Baron, Cooperstein, and Kahana incorporating general relativity and a new high density EOS are presented, and the relevance of these calculations to laboratory experiments with heavy ions considered. 31 refs., 6 figs., 2 tabs.

  5. Essential ingredients in core-collapse supernovae

    Directory of Open Access Journals (Sweden)

    W. Raphael Hix

    2014-03-01

    Full Text Available Carrying 1044 joules of kinetic energy and a rich mix of newly synthesized atomic nuclei, core-collapse supernovae are the preeminent foundries of the nuclear species which make up our solar system and ourselves. Signaling the inevitable death of a massive star, and the birth of a neutron star or black hole, core-collapse supernovae combine physics over a wide range in spatial scales, from kilometer-sized hydrodynamic motions (eventually growing to gigameter scale down to femtometer-scale nuclear reactions. We will discuss our emerging understanding of the convectively-unstable, neutrino-driven explosion mechanism, based on increasingly realistic neutrino radiation hydrodynamic simulations that include progressively better nuclear and particle physics. Multi-dimensional models with spectral neutrino transport from several research groups, which slowly develop successful explosions for a range of progenitors, have recently motivated changes in our understanding of the neutrino reheating mechanism. In a similar fashion, improvements in nuclear physics, most notably explorations of weak interactions on nuclei and the nuclear equation of state, continue to refine our understanding of the births of neutron stars and the supernovae that result. Recent progress on both the macroscopic and microscopic effects that affect core-collapse supernovae are discussed.

  6. Mutual influence of supernovae and molecular clouds

    CERN Document Server

    Iffrig, Olivier

    2014-01-01

    Context. Molecular clouds are known to be turbulent and strongly affected by stellar feedback. Moreover, stellar feedback is believed to be driving turbulence at large scales in galaxies. Aims. We study the role played by supernovae in molecular clouds and the influence of the magnetic field on this process. Methods. We perform three-dimensional numerical simulations of supernova explosions, in and near turbulent self-gravitating molecular clouds. In order to study the influence of the magnetic field, we perform both hydrodynamical and MHD simulations. We also run a series of simple uniform density medium simulations and develop a simple analytical model. Results. We find that the total amount of momentum that is delivered during supernova explosions typically varies by a factor of about 2 even when the gas density changes by 3 orders of magnitude. However, the amount of momentum delivered to the dense gas varies by almost a factor 10 if the supernova explodes within or outside the molecular cloud. The magnet...

  7. A catalogue of 294 Galactic supernova remnants

    CERN Document Server

    Green, D A

    2014-01-01

    A revised catalogue of 294 Galactic supernova remnants (SNRs) is presented, along with some simple statistics. This catalogue has twenty more entries than did the previous version (from 2009), as 21 new remnants have been added, and one object has been removed as it has been identified as an HII region.

  8. Rayleigh-Taylor mixing in supernova experiments

    Energy Technology Data Exchange (ETDEWEB)

    Swisher, N. C.; Abarzhi, S. I., E-mail: snezhana.abarzhi@gmail.com [Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Kuranz, C. C. [University of Michigan, Ann Arbor, Michigan 48109 (United States); Arnett, D. [University of Arizona, Tucson, Arizona 85721 (United States); Hurricane, O.; Remington, B. A.; Robey, H. F. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2015-10-15

    We report a scrupulous analysis of data in supernova experiments that are conducted at high power laser facilities in order to study core-collapse supernova SN1987A. Parameters of the experimental system are properly scaled to investigate the interaction of a blast-wave with helium-hydrogen interface, and the induced Rayleigh-Taylor instability and Rayleigh-Taylor mixing of the denser and lighter fluids with time-dependent acceleration. We analyze all available experimental images of the Rayleigh-Taylor flow in supernova experiments and measure delicate features of the interfacial dynamics. A new scaling is identified for calibration of experimental data to enable their accurate analysis and comparisons. By properly accounting for the imprint of the experimental conditions, the data set size and statistics are substantially increased. New theoretical solutions are reported to describe asymptotic dynamics of Rayleigh-Taylor flow with time-dependent acceleration by applying theoretical analysis that considers symmetries and momentum transport. Good qualitative and quantitative agreement is achieved of the experimental data with the theory and simulations. Our study indicates that in supernova experiments Rayleigh-Taylor flow is in the mixing regime, the interface amplitude contributes substantially to the characteristic length scale for energy dissipation; Rayleigh-Taylor mixing keeps order.

  9. Evidence for strange matter in supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Benvenuto, O.G.; Horvath, J.E. (Facultad de Ciencias Astronomicas y Geofiiaasicas, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina de La Plata, Calle 49 y 115, Casilla de Correo 67, 1900 La Plata, Argentina (AR))

    1989-08-14

    With the aim of overcoming the present energetic difficulties in getting type-II supernovae explosions, we present a possible scenario based on strange-matter formation. The observational expectations of this picture are discussed and the predictions of the model for SN 1987A neutrinos and remnant pulsar are examined.

  10. Classification of 9 DES supernova by Magellan

    Science.gov (United States)

    Challis, P.; Kirshner, R.; Mandel, K.; Avelino, A.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.

    2016-09-01

    We report optical spectroscopy of 9 supernovae discovered by the Dark Energy Survey (ATel #4668). The spectra were obtained using LDSS-3C (covering 420-950nm) on the 6.5m Clay telescope at the Las Campanas Observatory.

  11. Clustering of supernova Ia host galaxies

    CERN Document Server

    Carlberg, R G; Le Borgne, D; Conley, A; Howell, D A; Perrett, K; Astier, Pierre; Balam, D; Balland, C; Basa, S; Hardin, D; Fouchez, D; Guy, J; Hook, I; Pain, R; Pritchet, C J; Regnault, N; Rich, J; Perlmutter, S

    2008-01-01

    For the first time the cross-correlation between type Ia supernova host galaxies and surrounding field galaxies is measured using the Supernova Legacy Survey sample. Over the z=0.2 to 0.9 redshift range we find that supernova hosts are correlated an average of 60% more strongly than similarly selected field galaxies over the 3-100 arcsec range and about a factor of 3 more strongly below 10 arcsec. The correlation errors are empirically established with a jackknife analysis of the four SNLS fields. The hosts are more correlated than the field at a significance of 99% in the fitted amplitude and slope, with the point-by-point difference of the two correlation functions having a reduced $\\chi^2$ for 8 degrees of freedom of 4.3, which has a probability of random occurrence of less than 3x10^{-5}. The correlation angle is 1.5+/-0.5 arcsec, which deprojects to a fixed co-moving correlation length of approximately 6.5+/- 2/h mpc. Weighting the field galaxies with the mass and star formation rate supernova frequencie...

  12. The Extreme Hosts of Extreme Supernovae

    CERN Document Server

    Neill, James D; Gal-Yam, Avishay; Quimby, Robert; Ofek, Eran; Wyder, Ted K; Howell, D Andrew; Nugent, Peter; Seibert, Mark; Martin, D Christopher; Overzier, Roderik; Barlow, Tom A; Foster, Karl; Friedman, Peter G; Morrissey, Patrick; Neff, Susan G; Schiminovich, David; Bianchi, Luciana; Donas, José; Heckman, Timothy M; Lee, Young-Wook; Madore, Barry F; Milliard, Bruno; Rich, R Michael; Szalay, Alex S

    2010-01-01

    We use GALEX ultraviolet (UV) and optical integrated photometry of the hosts of seventeen luminous supernovae (LSNe, having peak M_V 100 M_sun), by appearing in low-SFR hosts, are potential tests for theories of the initial mass function that limit the maximum mass of a star based on the S FR.

  13. The Starlite Project

    Science.gov (United States)

    1990-09-01

    An Annual Progress Report N Contract No. N00014-86-K-0245 October 1, 1989 - September 30, 1990 THE STARLITE PROJECT Nl Applied Math and Computer...September 30, 1990 THE STARLITE PROJECT Applied Math and Computer Science Dr. James G. Smith Program Manager, Code 1211 Computer Science Division /77 Dr...1989 - Sent. 30, 19)0 4. TITLE AND SUBT1TU 5. FUNDING NUMBERS The StarLite Project -C-AUTOR(S)N00014-86-K-0245 P00002 R. P. Cook, S. H. Son 7. PEAORjI

  14. Scaling supernova hydrodynamics to the laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kane, J.O.

    1999-06-01

    Supernova (SN) 1987A focused attention on the critical role of hydrodynamic instabilities in the evolution of supernovae. To test the modeling of these instabilities, we are developing laboratory experiments of hydrodynamic mixing under conditions relevant to supernovae. Initial results were reported in J. Kane et al., Astrophys. J.478, L75 (1997) The Nova laser is used to shock two-layer targets, producing Richtmyer-Meshkov (RM) and Rayleigh-Taylor (RT) instabilities at the interfaces between the layers, analogous to instabilities seen at the interfaces of SN 1987A. Because the hydrodynamics in the laser experiments at intermediate times (3-40 ns) and in SN 1987A at intermediate times (5 s-10{sup 4} s) are well described by the Euler equations, the hydrodynamics scale between the two regimes. The experiments are modeled using the hydrodynamics codes HYADES and CALE, and the supernova code PROMETHEUS, thus serving as a benchmark for PROMETHEUS. Results of the experiments and simulations are presented. Analysis of the spike and bubble velocities in the experiment using potential flow theory and a modified Ott thin shell theory is presented. A numerical study of 2D vs. 3D differences in instability growth at the O-He and He-H interface of SN 1987A, and the design for analogous laser experiments are presented. We discuss further work to incorporate more features of the SN in the experiments, including spherical geometry, multiple layers and density gradients. Past and ongoing work in laboratory and laser astrophysics is reviewed, including experimental work on supernova remnants (SNRs). A numerical study of RM instability in SNRs is presented.

  15. 76 FR 52691 - Captain John Smith Chesapeake National Historic Trail Advisory Council

    Science.gov (United States)

    2011-08-23

    ... National Park Service Captain John Smith Chesapeake National Historic Trail Advisory Council AGENCY... Captain John Smith Chesapeake National Historic Trail will hold a meeting. Designated through an amendment..., Maryland, Delaware, and in the District of Columbia,'' tracing the 1607-1609 voyages of Captain John...

  16. An Alternative View of the Instructional Design Process: A Response to Smith and Boling

    Science.gov (United States)

    Gibbons, Andrew S.; Yanchar, Stephen C.

    2010-01-01

    A recent literature review by Smith and Boling (2009) critically examines the received view of instructional design in educational technology. Smith and Boling conclude that the foundational literature characterizes design in a way that leads to a constrained understanding of design, especially by novices. They suggest that as a field we move…

  17. Unconscious Odour Conditioning 25 Years Later: Revisiting and Extending "Kirk-Smith, Van Toller and Dodd"

    Science.gov (United States)

    Zucco, Gesualdo M.; Paolini, Michela; Schaal, Benoist

    2009-01-01

    The pioneering work by Kirk-Smith, Van Toller, and Dodd [Kirk-Smith, M. D., Van Toller, C., & Dodd, G. H. (1983). "Unconscious odour conditioning in human subjects." "Biological Psychology," 17, 221-231], established that an unnoticed odorant paired with an emotionally meaningful task can influence mood and attitudes when the odorant alone is…

  18. 76 FR 26767 - Captain John Smith Chesapeake National Historic Trail Advisory Council

    Science.gov (United States)

    2011-05-09

    ... National Park Service Captain John Smith Chesapeake National Historic Trail Advisory Council AGENCY... Captain John Smith Chesapeake National Historic Trail will hold a meeting. Designated through an amendment..., Maryland, Delaware, and in the District of Columbia,'' tracing the 1607-1609 voyages of Captain John...

  19. 77 FR 12324 - Captain John Smith Chesapeake National Historic Trail Advisory Council

    Science.gov (United States)

    2012-02-29

    ... National Park Service Captain John Smith Chesapeake National Historic Trail Advisory Council AGENCY... Captain John Smith Chesapeake National Historic Trail will hold a meeting. Designated through an amendment..., Maryland, Delaware, and in the District of Columbia,'' tracing the 1607-1609 voyages of Captain John...

  20. Smith-Petersen Vitallium mould arthroplasty: a 62-year follow-up.

    LENUS (Irish Health Repository)

    Baker, J F

    2011-09-01

    A variety of materials were used for early hip prostheses. The introduction of Vitallium by Smith-Petersen represented a further advance in this surgical field. We present the longest known follow-up of a Smith-Petersen Vitallium mould arthroplasty.

  1. The nature of social preference and interactions in Smith-Magenis syndrome.

    Science.gov (United States)

    Wilde, Lucy; Silva, Daniel; Oliver, Chris

    2013-12-01

    This natural observation study was designed to evaluate hypothesized elevated 'attention-seeking' and preference for adult attention in Smith-Magenis syndrome. Ten children with Smith-Magenis syndrome were observed across one school day, together with an age matched sample of 10 children with Down syndrome. Levels of attention given to, and vigilance for, adults and peers were recorded and compared. Sequences of behaviour were analyzed to evaluate the temporal relationships between giving and receiving attention during adult-child interactions. Compared to children with Down syndrome, children with Smith-Magenis syndrome gave preferential attention to adults and looked towards adults significantly more than they looked towards peers. Sequential analyses revealed that while children with Smith-Magenis syndrome did not initiate interactions with adults more than children with Down syndrome did, reciprocity between child and adult social behaviours in Smith-Magenis syndrome within interactions was compromised. This less synchronous sequence of child and adult interactions in Smith-Magenis syndrome may be the result of children with Smith-Magenis syndrome attempting to initiate interaction at times when it is unavailable. The marked preference for interacting with adults over peers in Smith-Magenis syndrome indicates atypicality of social interaction in this syndrome.

  2. The Behavioural Phenotype of Smith-Magenis Syndrome: Evidence for a Gene-Environment Interaction

    Science.gov (United States)

    Taylor, L.; Oliver, C.

    2008-01-01

    Background: Behaviour problems and a preference for adult contact are reported to be prominent in the phenotype of Smith-Magenis syndrome. In this study we examined the relationship between social interactions and self-injurious and aggressive/disruptive behaviour in Smith-Magenis syndrome to explore potential operant reinforcement of problem…

  3. At læse Adam Smith er både befriende og irriterende

    DEFF Research Database (Denmark)

    Larsen, Steen Nepper

    2014-01-01

    Anmeldelse af Adam Smith: "Teorien om de moralske følelser", oversat af Claus Bratt Østergaard, udg. på Informations Forlag......Anmeldelse af Adam Smith: "Teorien om de moralske følelser", oversat af Claus Bratt Østergaard, udg. på Informations Forlag...

  4. Comparison of the Smith-Purcell Radiation Yield for Different Models

    CERN Document Server

    Malovytsia, M S

    2016-01-01

    Smith-Purcell radiation is used in several applications including the measurement of the longitudinal profile of electron bunches. A correct reconstruction of such profile requires a good understanding of the underlying model. We have compared the leading models of Smith-Purcell radiation and shown that they are in agreement within the experimental errors.

  5. FEATURES OF INVESTMENT PROCESS UNDERSTANDING BY A. SMITH AS THE FOUNDER OF CLASSICAL THEORY

    Directory of Open Access Journals (Sweden)

    T. Ovcharenko

    2013-03-01

    Full Text Available The paper examines the essence and the nature of the concept of “investment”. The main conceptual elements of a scientific theory of Adam Smith are defined. The features of the investment process by Adam Smith as the driving mechanism for social and economic development of a society are revealed.

  6. Rhetorical Studies: A Reassessment of Adam Smith's Lectures on Rhetoric and Belles Lettres.

    Science.gov (United States)

    Purcell, William M.

    1986-01-01

    Offers a dissenting interpretation of Adam Smith's Lectures on Rhetoric and Belles Lettres and a more conservative perspective on Smith's significance to the history of rhetorical theory. Views the lectures as an historical commentary on literature and rhetoric from the perspective of an eighteenth-century lecturer. (JD)

  7. How To Survive in Postindustrial Environments: Adam Smith's Advice for Today's Colleges and Universities.

    Science.gov (United States)

    Ortmann, Andreas

    1997-01-01

    Adam Smith's discussion of the payment modes of teachers and resulting consequences for the quality of teaching and process of curricular innovation are reviewed through the conceptual lens of modern agency theory. Smith's analysis of higher education in his day (eighteenth century) sheds light on faculty incentive and assessment problems that…

  8. Two Rival Conceptions of Vocational Education: Adam Smith and Friedrich List.

    Science.gov (United States)

    Winch, Christopher

    1998-01-01

    Examines and discusses two views of political economy: (1) the classical model of Adam Smith; and (2) the social capitalist model associated with Friedrich List. Explores two varieties of vocational education and training that emerge from a comparison of Smith's and List's ideas. (CMK)

  9. A Helping Hand in the Frederick Community—Ross Smith | Poster

    Science.gov (United States)

    By day, Ross Smith is the compliance and security officer for Data Management Services, Inc., assigned to the National Cancer Institute (NCI) at Frederick. His role is to ensure the secure operation of in-house computer systems, servers, and network connections. But in his spare time, Smith is also a volunteer firefighter and emergency medical technician (EMT).

  10. A Disciplinary Immigrant. Alexander Smith at the University of Chicago, 1894-1911

    Science.gov (United States)

    Cotter, Donald

    2008-01-01

    The publication in 1906 of Alexander Smith's "Introduction to general inorganic chemistry" inaugurated a decisive change in chemical pedagogy in the US, the effects of which are still evident. The nature and extent of Smith's innovations are described through a comparison of his text to its source material and contemporaries. His…

  11. Unconscious Odour Conditioning 25 Years Later: Revisiting and Extending "Kirk-Smith, Van Toller and Dodd"

    Science.gov (United States)

    Zucco, Gesualdo M.; Paolini, Michela; Schaal, Benoist

    2009-01-01

    The pioneering work by Kirk-Smith, Van Toller, and Dodd [Kirk-Smith, M. D., Van Toller, C., & Dodd, G. H. (1983). "Unconscious odour conditioning in human subjects." "Biological Psychology," 17, 221-231], established that an unnoticed odorant paired with an emotionally meaningful task can influence mood and attitudes when the odorant alone is…

  12. 77 FR 64411 - Safety Zone; Cooper T. Smith Fireworks Event; Mobile River; Mobile, AL

    Science.gov (United States)

    2012-10-22

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Cooper T. Smith Fireworks Event; Mobile... establishing a temporary safety zone for a portion of the Mobile River, Mobile, AL in the vicinity of Cooper... during the Cooper T. Smith Fireworks Event. Entry into, transiting or anchoring in this zone...

  13. Rhetorical Studies: A Reassessment of Adam Smith's Lectures on Rhetoric and Belles Lettres.

    Science.gov (United States)

    Purcell, William M.

    1986-01-01

    Offers a dissenting interpretation of Adam Smith's Lectures on Rhetoric and Belles Lettres and a more conservative perspective on Smith's significance to the history of rhetorical theory. Views the lectures as an historical commentary on literature and rhetoric from the perspective of an eighteenth-century lecturer. (JD)

  14. How To Survive in Postindustrial Environments: Adam Smith's Advice for Today's Colleges and Universities.

    Science.gov (United States)

    Ortmann, Andreas

    1997-01-01

    Adam Smith's discussion of the payment modes of teachers and resulting consequences for the quality of teaching and process of curricular innovation are reviewed through the conceptual lens of modern agency theory. Smith's analysis of higher education in his day (eighteenth century) sheds light on faculty incentive and assessment problems that…

  15. Two Rival Conceptions of Vocational Education: Adam Smith and Friedrich List.

    Science.gov (United States)

    Winch, Christopher

    1998-01-01

    Examines and discusses two views of political economy: (1) the classical model of Adam Smith; and (2) the social capitalist model associated with Friedrich List. Explores two varieties of vocational education and training that emerge from a comparison of Smith's and List's ideas. (CMK)

  16. Speech/Language Pathologists Reflect on Sally Smith and the Lab School of Washington

    Science.gov (United States)

    Learning Disabilities: A Multidisciplinary Journal, 2010

    2010-01-01

    Sally L. Smith had a clear vision of how she thought speech and language services should be integrated into her school, The Lab School of Washington. It was Smith's idea that language therapists should work individually with students to help them make gains in their particular areas of need, as well as to work collaboratively with the teachers,…

  17. Smith-Purcell radiation emission in aperiodic arrays

    Science.gov (United States)

    Saavedra, J. R. M.; Castells-Graells, D.; García de Abajo, F. Javier

    2016-07-01

    We study the Smith-Purcell light emission produced by electrons moving parallel to linear aperiodic particle arrays. This constitutes a generalization of this type of phenomenon from periodic to aperiodic structures. As in the periodic case, the emission is found to exhibit intense features in its angular and frequency distributions, associated with the condition of constructive interference between the contributions arising from different particles in the array. This condition can also be expressed in terms of momentum conservation involving reciprocal wave-vector transfers from the array. We consider two examples of quasiperiodic and hyperuniform aperiodic arrays that allow us to illustrate this idea. Our study provides insight into the interaction of fast electrons with aperiodic arrays characterized by strong features in reciprocal space, which dominate the electron-array coupling.

  18. Smith-Magenis syndrome in Puerto Rico: a case report.

    Science.gov (United States)

    Jardón, Javier; Izquierdo, Natalio J

    2009-01-01

    Smith-Magenis syndrome (SMS) is characterized by deletions in the short arm of chromosome 17. Systemic findings in patients with the syndrome include: dysmorphic facies and skeletal deformities. Ophthalmic findings in patients with the SMS include: strabismus, refractive errors, microcornea, iris anomalies, microphthalmos, and coloboma. A 14-year-old boy with cytogenetic studies confirming the SMS underwent a comprehensive ophthalmologic examination. The patient has a history of strabismus surgery. Clinical findings in this patient include: developmental delay, facial dysmorphism, enamel hypoplasia, short broad hands, clinodactyly, and scoliosis. Ocular findings in our patient include: myopia, iris nodules, loose zonules, and ectopia lentis. To our knowledge this is the first reported case of SMS in the Caribbean basin and the first case that report ectopia lentis in SMS. There is a possibility that lens subluxation in our patient is due to self inflicted trauma.

  19. Periventricular nodular heterotopia in Smith-Magenis syndrome.

    Science.gov (United States)

    Capra, Valeria; Biancheri, Roberta; Morana, Giovanni; Striano, Pasquale; Novara, Francesca; Ferrero, Giovanni Battista; Boeri, Luca; Celle, Maria Elena; Mancardi, Maria Margherita; Zuffardi, Orsetta; Parrini, Elena; Guerrini, Renzo

    2014-12-01

    Smith-Magenis syndrome (SMS) is caused by an interstitial microdeletion of chromosome 17p11.2. A few patients with the typical SMS phenotype have RAI1 gene mutations. The syndrome is characterized by minor craniofacial anomalies, short stature, sleep disturbances, behavioural and neurocognitive abnormalities, as well as variable multisystemic manifestations. Periventricular nodular heterotopia (PNH) is a genetically heterogeneous neuronal migration disorder characterized by subependymal heterotopic nodules, and is variably associated with other brain malformations, epileptic seizures and intellectual disability. Here we report on two patients harboring deletions of the 17p11.2 region in whom the SMS typical phenotype was associated with bilateral PNH. Our observations expand the spectrum of chromosomal rearrangements associated with PNH and indicate that abnormal neuronal migration may contribute to the neurocognitive phenotype of SMS.

  20. A new modified Smith predictor: the concept, design and tuning.

    Science.gov (United States)

    Vrecko, D; Vrancić, D; Juricić, D; Strmcnik, S

    2001-01-01

    The paper presents a new modified Smith predictor (MSP) for processes with a long time delay. The MSP appears as an extension of the double controller-scheme (DCS) proposed by Tian and Gao. The important feature of the MSP is that the trade-off between disturbance rejection and robustness to variations in process parameters can be adjusted by means of a single free parameter. The main contribution of the paper concerns tuning of the MSP, which relies on a combination of magnitude optimum criterion with process parameterisation based on multiple integrals of the open-loop step response. In a simulation study the performance of the MSP is compared with that of two known controllers for time delay systems, i.e. DCS of Tian and Gao and Hägglund's predictive PI controller. The results show the advantage of the MSP compared to the two other controllers.