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Sample records for supernova sn explosions

  1. 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...

  2. Three-dimensional hydrodynamic modeling of SN 1987A from the supernova explosion till the Athena era

    Science.gov (United States)

    Orlando, Salvatore

    2016-06-01

    The proximity of SN 1987A and the wealth of observations collected at all wavelenght bands since its outburst allow us to study in details the evolution of a supernova remnant (SNR) from the immediate aftermath of the SN explosion till its expansion through the highly inhomogeneous circumstellar medium (CSM). We investigate the interaction between SN 1987A and the surrounding CSM through three-dimensional hydrodynamic modeling. The aim is to determine the contribution of shocked ejecta and shocked CSM to the detected X-ray flux and to derive the density structure of the inhomogeneous CSM and clues on the early structure of ejecta. We show that the physical model reproducing the main observables of SN 1987A 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 constrain the explosion energy in the range 1.2 - 1.4 × 10^(51) erg and the envelope mass in the range 15 - 17 M_{⊙}) . We find that the shape of X-ray lightcurves and spectra at early epochs (environment, and to constrain the pre-supernova structure of the nebula. Finally the remnant evolution is followed for 40 years, providing predictions on the future of SN 1987A until the adventof Athena.

  3. TYPE IIn SUPERNOVA SN 2010jl: OPTICAL OBSERVATIONS FOR OVER 500 DAYS AFTER EXPLOSION

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Tianmeng; Wu Chao; Zhai Meng; Wu Hong; Fan Zhou; Zou Hu; Zhou Xu; Ma Jun [National Astronomical Observatories of China, Chinese Academy of Sciences, Beijing 100012 (China); Wang Xiaofeng; Chen Juncheng; Chen Jia; Liu Qin; Huang Fang; Liang Jide; Zhao Xulin [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Lin Lin [Center for Astrophysics, University of Science and Technology of China, No. 96, JinZhai Road Baohe District, Hefei, Anhui 230026 (China); Wang Min [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, 210008 (China); Dennefeld, Michel [Institut d' Astrophysique de Paris, and University Pierre et Marie Curie (Paris 6) (France); Zhang Jujia, E-mail: armengjade@gmail.com, E-mail: wang_xf@mail.tsinghua.edu.cn [Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011 (China)

    2012-11-01

    We present extensive optical observations of a Type IIn supernova (SN IIn) 2010jl for the first 1.5 years after its discovery. The UBVRI light curves demonstrated an interesting two-stage evolution during the nebular phase, which almost flatten out after about 90 days from the optical maximum. SN 2010jl has one of the highest intrinsic H{alpha} luminosities ever recorded for an SN IIn, especially at late phase, suggesting a strong interaction of SN ejecta with the dense circumstellar material (CSM) ejected by the progenitor. This is also indicated by the remarkably strong Balmer lines persisting in the optical spectra. One interesting spectral evolution about SN 2010jl is the appearance of asymmetry of the Balmer lines. These lines can be well decomposed into a narrow component and an intermediate-width component. The intermediate-width component showed a steady increase in both strength and blueshift with time until t {approx} 400 days after maximum, but it became less blueshifted at t {approx} 500 days, when the line profile appeared relatively symmetric again. Owing to the fact that a pure reddening effect will lead to a sudden decline of the light curves and a progressive blueshift of the spectral lines, we therefore propose that the asymmetric profiles of H lines seen in SN 2010jl are unlikely due to the extinction by newly formed dust inside the ejecta, contrary to the explanation by some early studies. Based on a simple CSM-interaction model, we speculate that the progenitor of SN 2010jl may suffer a gigantic mass loss ({approx}30-50 M{sub Sun }) a few decades before explosion. Considering a slow-moving stellar wind (e.g., {approx}28 km s{sup -1}) inferred for the preexisting, dense CSM shell and the extremely high mass-loss rate (1-2 M{sub Sun} yr{sup -1}), we suggest that the progenitor of SN 2010jl might have experienced a red supergiant stage and may explode finally as a post-red supergiant star with an initial mass above 30-40 M{sub Sun }.

  4. Type IIn Supernova SN 2010jl: Optical Observations for Over 500 Days After Explosion

    CERN Document Server

    Zhang, Tianmeng; Wu, Chao; Chen, Juncheng; Chen, Jia; Liu, Qin; Huang, Fang; Liang, Jide; Zhao, Xulin; Li, Lin; Wang, Min; Dennefeld, Michel; Zhang, Jujia; Zhai, Meng; Wu, Hong; Fan, Zhou; Zou, Hu; Zhou, Xu; Ma, Jun

    2012-01-01

    We present extensive optical observations of a Type IIn supernova (SN) 2010jl for the first 1.5 years after the discovery. The UBVRI light curves demonstrated an interesting two-stage evolution during the nebular phase, which almost flatten out after about 90 days from the optical maximum. SN 2010jl has one of the highest intrinsic H_alpha luminosity ever recorded for a SN IIn, especially at late phase, suggesting a strong interaction of SN ejecta with the dense circumstellar material (CSM) ejected by the progenitor. This is also indicated by the remarkably strong Balmer lines persisting in the optical spectra. One interesting spectral evolution about SN 2010jl is the appearance of asymmetry of the Balmer lines. These lines can be well decomposed into a narrow component and an intermediate-width component. The intermediate-width component showed a steady increase in both strength and blueshift with time until t ~ 400 days after maximum, but it became less blueshifted at t ~ 500 days when the line profile appe...

  5. Supernova Explosions in Winds and Bubbles, with Applications to SN 1987A

    Directory of Open Access Journals (Sweden)

    Vikram V. Dwarkadas

    2007-01-01

    Full Text Available Las estrellas masivas pueden modi car signi cativamente el medio que las rodea durante sus vidas. Cuando las estrellas explotan como supernovas, la onda de choque resultante se expande dentro de este medio modi cado y no en el medio interestelar. Exploramos la evoluci on del medio alrededor de las estrellas masivas, y la expansi on de la onda de choque dentro de este medio. Entonces aplicamos estos resultados para comprender la expansi on de la onda de choque en el medio ambiente que rodea a SN 1987A, y la evoluci on de la emisi on en radio y rayos X en este caso

  6. 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.

  7. 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.

  8. 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...

  9. Spectropolarimetry of SN 2011dh in M51: geometric insights on a Type IIb supernova progenitor and explosion

    CERN Document Server

    Mauerhan, Jon C; Leonard, Douglas C; Smith, Paul S; Filippenko, Alexei V; Smith, Nathan; Hoffman, Jennifer L; Huk, Leah; Clubb, Kelsey I; Silverman, Jeffrey M; Cenko, S Bradley; Milne, Peter; Gal-Yam, Avishay; Ben-Ami, Sagi

    2015-01-01

    We present seven epochs of spectropolarimetry of the Type IIb supernova (SN) 2011dh in M51, spanning 86 days of its evolution. The first epoch was obtained 9 days after the explosion, when the photosphere was still in the depleted hydrogen layer of the stripped-envelope progenitor. Continuum polarization is securely detected at the level of P~0.5% through day 14 and appears to diminish by day 30, which is different from the prevailing trends suggested by studies of other core-collapse SNe. Time-variable modulations in P and position angle are detected across P-Cygni line features. H-alpha and HeI polarization peak after 30 days and exhibit position angles roughly aligned with the earlier continuum, while OI and CaII appear to be geometrically distinct. We discuss several possibilities to explain the evolution of the continuum and line polarization, including the potential effects of a tidally deformed progenitor star, aspherical radioactive heating by fast-rising plumes of Ni-56 from the core, oblique shock b...

  10. Superluminous Supernova SN 2015bn in the Nebular Phase: Evidence for the Engine-powered Explosion of a Stripped Massive Star

    Science.gov (United States)

    Nicholl, M.; Berger, E.; Margutti, R.; Chornock, R.; Blanchard, P. K.; Jerkstrand, A.; Smartt, S. J.; Arcavi, I.; Challis, P.; Chambers, K. C.; Chen, T.-W.; Cowperthwaite, P. S.; Gal-Yam, A.; Hosseinzadeh, G.; Howell, D. A.; Inserra, C.; Kankare, E.; Magnier, E. A.; Maguire, K.; Mazzali, P. A.; McCully, C.; Milisavljevic, D.; Smith, K. W.; Taubenberger, S.; Valenti, S.; Wainscoat, R. J.; Yaron, O.; Young, D. R.

    2016-09-01

    We present nebular-phase imaging and spectroscopy for the hydrogen-poor superluminous supernova (SLSN) SN 2015bn, at redshift z = 0.1136, spanning +250-400 days after maximum light. The light curve exhibits a steepening in the decline rate from 1.4 mag (100 days)-1 to 1.7 mag (100 days)-1, suggestive of a significant decrease in the opacity. This change is accompanied by a transition from a blue continuum superposed with photospheric absorption lines to a nebular spectrum dominated by emission lines of oxygen, calcium, and magnesium. There are no obvious signatures of circumstellar interaction or large 56Ni mass. We show that the spectrum at +400 days is virtually identical to a number of energetic SNe Ic such as SN 1997dq, SN 2012au, and SN 1998bw, indicating similar core conditions and strengthening the link between “hypernovae”/long gamma-ray bursts and SLSNe. A single explosion mechanism may unify these events that span absolute magnitudes of -22 < M B < -17. Both the light curve and spectrum of SN 2015bn are consistent with an engine-driven explosion ejecting 7-30 M ⊙ of oxygen-dominated ejecta (for reasonable choices in temperature and opacity). A strong and relatively narrow O i λ7774 line, seen in a number of these energetic events but not in normal supernovae, may point to an inner shell that is the signature of a central engine.

  11. Impact of Supernova Explosions on Galaxy Formation

    CERN Document Server

    Scannapieco, C; White, S D M; Springel, V

    2006-01-01

    We study the effects of Supernova (SN) feedback on the formation of disc galaxies. For that purpose we run simulations using the extended version of the code GADGET-2 which includes a treatment of chemical and energy feedback by SN explosions. We found that our model succeeds in setting a self-regulated star formation process since an important fraction of the cold gas from the center of the haloes is efficiently heated up and transported outwards. The impact of SN feedback on galactic systems is also found to depend on virial mass: smaller systems are more strongly affected with star formation histories in which several starbursts can develop. Our implementation of SN feedback is also successful in producing violent outflows of chemical enriched material.

  12. SN 1987A: The Supernova of the Century

    Science.gov (United States)

    Sonneborne, George

    2012-01-01

    Supernova 1987 A in the Large Magellanic Cloud is one of the most intensively studied objects in the universe and a Rosetta Stone for understanding the explosions of massive stars. Approaching its 25th anniversary, SN 1987 A is a very young supernova remnant, a phase previously unobserved in any other supernova. The supernova of the 20th Century is now the supernova remnant of the 21st Century. In this talk I will discuss recent observations from the far-ultraviolet to the far-infrared with HST, the VLT, Spitzer, and the Herschel Space Observatory. These data reveal new insights into the composition, geometry, and heating of the explosion debris, the shock interaction with circumstellar material, and dust in the SN 1987 A system.

  13. Thermonuclear supernova explosions and their remnants: the case of Tycho

    CERN Document Server

    Badenes, C; Borkowski, K J; Badenes, Carles; Bravo, Eduardo; Borkowski, Kazimierz J.

    2003-01-01

    We propose to use the thermal X-ray emission from young supernova remnants (SNRs) originated in Type Ia supernovae (SNe) to extract relevant information concerning the explosion mechanism. We will focus on the differences between numerical 1D and 3D explosion calculations, and the impact that these differences could have on young SNRs. We use the remnant of the Tycho supernova (SN 1572) as a test case to compare with our predictions, discussing the observational features that allow to accept or discard a given model.

  14. Type Ia supernovae: explosions and progenitors

    Science.gov (United States)

    Kerzendorf, Wolfgang Eitel

    2011-08-01

    Supernovae are the brightest explosions in the universe. Supernovae in our Galaxy, rare and happening only every few centuries, have probably been observed since the beginnings of mankind. At first they were interpreted as religious omens but in the last half millennium they have increasingly been used to study the cosmos and our place in it. Tycho Brahe deduced from his observations of the famous supernova in 1572, that the stars, in contrast to the widely believe Aristotelian doctrine, were not immutable. More than 400 years after Tycho made his paradigm changing discovery using SN 1572, and some 60 years after supernovae had been identified as distant dying stars, two teams changed the view of the world again using supernovae. The found that the Universe was accelerating in its expansion, a conclusion that could most easily be explained if more than 70% of the Universe was some previously un-identified form of matter now often referred to as `Dark Energy'. Beyond their prominent role as tools to gauge our place in the Universe, supernovae themselves have been studied well over the past 75 years. We now know that there are two main physical causes of these cataclysmic events. One of these channels is the collapse of the core of a massive star. The observationally motivated classes Type II, Type Ib and Type Ic have been attributed to these events. This thesis, however is dedicated to the second group of supernovae, the thermonuclear explosions of degenerate carbon and oxygen rich material and lacking hydrogen - called Type Ia supernovae (SNe Ia). White dwarf stars are formed at the end of a typical star's life when nuclear burning ceases in the core, the outer envelope is ejected, with the degenerate core typically cooling for eternity. Theory predicts that such stars will self ignite when close to 1.38 Msun (called the Chandrasekhar Mass). Most stars however leave white dwarfs with 0.6 Msun, and no star leaves a remnant as heavy as 1.38 M! sun, which suggests

  15. 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.

  16. The Role of Nucleon Strangeness in Supernova Explosions

    CERN Document Server

    Hobbs, T J; Miller, Gerald A

    2016-01-01

    Recent hydrodynamical simulations of supernova (SN) evolution have highlighted the importance of a thorough control over microscopic physics responsible for such internal processes as neutrino heating. In particular, it has been suggested that modifications to the neutrino-nucleon elastic cross section can potentially play a crucial role in producing successful supernova explosions. One possible source of such corrections can be found in a nonzero value for the nucleon's strange helicity content $\\Delta s$. In the present analysis, however, we show that theoretical and experimental progress over the past decade has suggested a comparatively small magnitude for $\\Delta s$, such that its sole effect is not sufficient to provide the physics leading to supernova explosions.

  17. Alfven Wave-Driven Supernova Explosion

    CERN Document Server

    Suzuki, T K; Yamada, S

    2007-01-01

    We investigate the role of Alfven waves in the core-collapse supernova (SN) explosion. We assume that Alfven waves are generated by convections inside a proto-neutron star (PNS) and emitted from its surface. Then these waves propagate outwards and dissipate via nonlinear processes and heat up matter around a stalled prompt shock. To quantitatively assess the importance of this process for revival of the stalled shock, we perform 1D time-dependent hydrodynamical simulations, taking into account the heating via the dissipation of Alfven waves. We show that the shock revival occurs if the surface field strength is larger than ~2x10^{15}G and if the amplitude of velocity fluctuation at the PNS surface is larger than ~ 20% of the local sound speed. Interestingly, the Alfven wave mechanism is self-regulating in the sense that the explosion energy is not very sensitive to the surface field strength and initial amplitude of Alfven waves as long as they are larger than the threshold values given above. It should be em...

  18. 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.

  19. 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...

  20. Supernova 2007bi as a pair-instability explosion.

    Science.gov (United States)

    Gal-Yam, A; Mazzali, P; Ofek, E O; Nugent, P E; Kulkarni, S R; Kasliwal, M M; Quimby, R M; Filippenko, A V; Cenko, S B; Chornock, R; Waldman, R; Kasen, D; Sullivan, M; Beshore, E C; Drake, A J; Thomas, R C; Bloom, J S; Poznanski, D; Miller, A A; Foley, R J; Silverman, J M; Arcavi, I; Ellis, R S; Deng, J

    2009-12-03

    Stars with initial masses such that 10M[symbol: see text] supernova. By contrast, extremely massive stars with M(initial) >or= 140M[symbol: see text] (if such exist) develop oxygen cores with masses, M(core), that exceed 50M[symbol: see text], where high temperatures are reached at relatively low densities. Conversion of energetic, pressure-supporting photons into electron-positron pairs occurs before oxygen ignition and leads to a violent contraction which triggers a nuclear explosion that unbinds the star in a pair-instability supernova. Transitional objects with 100M[symbol: see text] supernovae following violent mass ejections, perhaps as a result of brief episodes of pair instability, and may already have been identified. Here we report observations of supernova SN 2007bi, a luminous, slowly evolving object located within a dwarf galaxy. We estimate the exploding core mass to be M(core) approximately 100M[symbol: see text], in which case theory unambiguously predicts a pair-instability supernova. We show that >3M[symbol: see text] of radioactive (56)Ni was synthesized during the explosion and that our observations are well fitted by models of pair-instability supernovae. This indicates that nearby dwarf galaxies probably host extremely massive stars, above the apparent Galactic stellar mass limit, which perhaps result from processes similar to those that created the first stars in the Universe.

  1. The circumstellar medium of the peculiar supernova SN1997ab

    CERN Document Server

    Salamanca, I M; Tenorio-Tagle, G; Telles, E; Terlevich, R J; Muñoz-Tunón, C; Salamanca, Isabel; Cid-Fernandes, Roberto; Tenorio-Tagle, Guillermo; Telles, Eduardo; Terlevich, Roberto J.; Munoz-Tunon, Casiana

    1998-01-01

    We report the detection of the slow moving wind into which the compact supernova remnant SN 1997ab is expanding. Echelle spectroscopy provides clear evidence for a well resolved narrow (Full Width at Zero Intensity, FWZI ~ 180 km/s) P-Cygni profile, both in Ha and Hb, superimposed on the broad emission lines of this compact supernova remnant. From theoretical arguments we know that the broad and strong emission lines imply a circumstellar density (n ~ 10^7 cm^-3). This, together with our detection, implies a massive and slow stellar wind experienced by the progenitor star shortly prior to the explosion.

  2. 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.

  3. Rapidly Decaying Supernova 2010X: A Candidate ".Ia" Explosion

    CERN Document Server

    Kasliwal, Mansi M; Gal-Yam, Avishay; Yaron, Ofer; Quimby, Robert M; Ofek, Eran O; Nugent, Peter; Poznanski, Dovi; Jacobsen, Janet; Sternberg, Assaf; Arcavi, Iair; Howell, D Andrew; Sullivan, Mark; Rich, Douglas J; Burke, Paul F; MD, Joseph Brimacombe MB ChB FRCA; Milisavljevic, Dan; Fesen, Robert; Bildsten, Lars; Shen, Ken; Cenko, S Bradley; Bloom, Joshua S; Hsiao, Eric; Law, Nicholas M; Gehrels, Neil; Immler, Stefan; Dekany, Richard; Rahmer, Gustavo; Hale, David; Smith, Roger; Zolkower, Jeff; Velur, Viswa; Walters, Richard; Henning, John; Bui, Kahnh; McKenna, Dan

    2010-01-01

    We present the discovery, photometric and spectroscopic follow-up observations of SN 2010X (PTF 10bhp). This supernova decays exponentially with tau_d=5 days, and rivals the current recordholder in speed, SN 2002bj. SN 2010X peaks at M_r=-17mag and has mean velocities of 10,000 km/s. Our light curve modeling suggests a radioactivity powered event and an ejecta mass of 0.16 Msun. If powered by Nickel, we show that the Nickel mass must be very small (0.02 Msun) and that the supernova quickly becomes optically thin to gamma-rays. Our spectral modeling suggests that SN 2010X and SN 2002bj have similar chemical compositions and that one of Aluminum or Helium is present. If Aluminum is present, we speculate that this may be an accretion induced collapse of an O-Ne-Mg white dwarf. If Helium is present, all observables of SN 2010X are consistent with being a thermonuclear Helium shell detonation on a white dwarf, a ".Ia" explosion. With the 1-day dynamic-cadence experiment on the Palomar Transient Factory, we expect ...

  4. Rapidly Decaying Supernova 2010X: A Candidate ".Ia" Explosion

    Science.gov (United States)

    Kasliwal, Mansi M.; Kulkarni, S. R.; Gal-Yam, Avishay; Yaron, Ofer; Quimby, Robert M.; Ofek, Eran O.; Nugent, Peter; Poznanski, Dovi; Jacobsen, Janet; Sternberg, Assaf; Arcavi, Iair; Howell, D. Andrew; Sullivan, Mark; Rich, Douglas J.; Burke, Paul F.; Brimacombe, Joseph; Milisavljevic, Dan; Fesen, Robert; Bildsten, Lars; Shen, Ken; Cenko, S. Bradley; Bloom, Joshua S.; Hsiao, Eric; Law, Nicholas M.; Gehrels, Neil; Immler, Stefan; Dekany, Richard; Rahmer, Gustavo; Hale, David; Smith, Roger; Zolkower, Jeff; Velur, Viswa; Walters, Richard; Henning, John; Bui, Kahnh; McKenna, Dan

    2010-11-01

    We present the discovery, photometric, and spectroscopic follow-up observations of SN 2010X (PTF 10bhp). This supernova decays exponentially with τ d = 5 days and rivals the current recordholder in speed, SN 2002bj. SN 2010X peaks at M r = -17 mag and has mean velocities of 10,000 km s-1. Our light curve modeling suggests a radioactivity-powered event and an ejecta mass of 0.16 M sun. If powered by Nickel, we show that the Nickel mass must be very small (≈0.02 M sun) and that the supernova quickly becomes optically thin to γ-rays. Our spectral modeling suggests that SN 2010X and SN 2002bj have similar chemical compositions and that one of aluminum or helium is present. If aluminum is present, we speculate that this may be an accretion-induced collapse of an O-Ne-Mg white dwarf. If helium is present, all observables of SN 2010X are consistent with being a thermonuclear helium shell detonation on a white dwarf, a ".Ia" explosion. With the 1 day dynamic-cadence experiment on the Palomar Transient Factory, we expect to annually discover a few such events.

  5. The broad line type Ic supernova SN 2007ru: Adding to the diversity of type Ic supernovae

    CERN Document Server

    Sahu, D K; Anupama, G C; Gurugubelli, Uday K; Nomoto, Ken'ichi

    2008-01-01

    Photometric and spectral evolution of the type Ic supernova SN 2007ru during the first 3 months are presented. The spectra show broad spectral features due to very high expansion velocity, normally seen in hypernovae. The photospheric velocity is higher than other type Ic supernovae. It is lower than SN 1998bw at $\\sim$ 8 days after the explosion, but is comparable at later epochs. The light curve evolution of SN 2007ru indicates a fast rise time of 8$\\pm$3 days to $B$ band maximum and post-maximum decline more rapidly than other broad-line type Ic supernovae.With an absolute $V$ magnitude of -19.10, SN 2007ru is comparable in brightness with SN 1998bw and lies at the brighter end of the observed type Ic supernovae. The mass of \\Nifs is estimated to be $\\sim 0.4\\Msun$. The fast rise and decline of the light curve and the high expansion velocity suggest that SN 2007ru is an explosion with a high kinetic energy/ejecta mass ratio ($E_{\\rm K}/M_{\\rm {ej}}$). This adds to the diversity of type Ic supernovae.

  6. Could a nearby supernova explosion have caused a mass extinction?

    CERN Document Server

    Ellis, Jonathan Richard

    1995-01-01

    We examine the possibility that a nearby supernova explosion could have caused one or more of the mass extinctions identified by palaeontologists. We discuss the likely rate of such events in the light of the recent identification of Geminga as a supernova remnant less than 100 pc away and the discovery of a millisecond pulsar about 150 pc away, and observations of SN 1987A. The fluxes of $\\gamma$ radiation and charged cosmic rays on the Earth are estimated, and their effects on the Earth's ozone layer discussed. A supernova explosion of the order of 10 pc away could be expected every few hundred million years, and could destroy the ozone layer for hundreds of years, letting in potentially lethal solar ultraviolet radiation. In addition to effects on land ecology, this could entail mass destruction of plankton and reef communities, with disastrous consequences for marine life as well. A supernova extinction should be distinguishable from a meteorite impact such as the one that presumably killed the dinosaurs.

  7. 44Ti gamma-ray emission lines from SN1987A reveal an asymmetric explosion

    DEFF Research Database (Denmark)

    Boggs, S. E.; Harrison, F. A.; Miyasaka, H.

    2015-01-01

    In core-collapse supernovae, titanium-44 (44Ti) is produced in the innermost ejecta, in the layer of material directly on top of the newly formed compact object. As such, it provides a direct probe of the supernova engine. Observations of supernova 1987A (SN1987A) have resolved the 67.87- and 78........32–kilo–electron volt emission lines from decay of 44Ti produced in the supernova explosion. These lines are narrow and redshifted with a Doppler velocity of ~700 kilometers per second, direct evidence of large-scale asymmetry in the explosion....

  8. Ti-44 Gamma-Ray Emission Lines from SN1987A Reveal an Asymmetric Explosion

    Science.gov (United States)

    Boggs, S. E.; Harrison, F. A.; Miyasaka, H.; Grefenstette, B. W.; Zoglauer, A.; Fryer, C. L.; Reynolds, S. P.; Alexander, D. M.; An, H.; Barret, D.; Christensen, F. E.; Craig, W. W.; Forster, K.; Giommi, P.; Hailey, C. J.; Hornstrup, A.; Kitaguchi, T.; Koglin, J. E.; Madsen, K. K.; Zhang, W. W.

    2015-01-01

    In core-collapse supernovae, titanium-44 (Ti-44) is produced in the innermost ejecta, in the layer of material directly on top of the newly formed compact object. As such, it provides a direct probe of the supernova engine. Observations of supernova 1987A (SN1987A) have resolved the 67.87- and 78.32-kilo-electron volt emission lines from decay of Ti-44 produced in the supernova explosion. These lines are narrow and redshifted with a Doppler velocity of 700 kilometers per second, direct evidence of large-scale asymmetry in the explosion.

  9. Effects of Dimensionality on Pair-Instability Supernova Explosions

    CERN Document Server

    Gilmer, Matthew S; Hirschi, Raphael; Fröhlich, Carla

    2016-01-01

    Since the emergence of the new class of extremely bright transients, super-luminous supernovae (SLSNe), three main mechanisms to power their light curves (LCs) have been discussed. They are the spin-down of a magnetar, interaction with circumstellar material, and the decay of large amounts of radioactive nickel in pair-instability supernovae (PISNe). Given the high degree of diversity seen within the class, it is possible that all three mechanisms are at work. PISN models can be self- consistently simulated from the main sequence phase of very massive stars (VMS) through to their explosion. These models robustly predict large amounts of radioactive nickel and thus very luminous SN events. However, PISN model LCs evolve more slowly than even the slowest evolving SLSNe. Multidimensional effects on the ejecta structure, specifically the mixing of radioactive nickel out to large radii, could alleviate this discrepancy with observation. Here we explore the multidimensional effects on the LC evolution by simulating...

  10. Neutrino oscillations in magnetically driven supernova explosions

    Energy Technology Data Exchange (ETDEWEB)

    Kawagoe, Shio; Kotake, Kei [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan); Takiwaki, Tomoya, E-mail: shio.k@nao.ac.jp, E-mail: takiwaki.tomoya@nao.ac.jp, E-mail: kkotake@th.nao.ac.jp [Center for Computational Astrophysics, National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan)

    2009-09-01

    We investigate neutrino oscillations from core-collapse supernovae that produce magnetohydrodynamic (MHD) explosions. By calculating numerically the flavor conversion of neutrinos in the highly non-spherical envelope, we study how the explosion anisotropy has impacts on the emergent neutrino spectra through the Mikheyev-Smirnov-Wolfenstein effect. In the case of the inverted mass hierarchy with a relatively large θ{sub 13} (sin{sup 2} 2θ{sub 13} ∼> 10{sup −3}), we show that survival probabilities of ν-bar {sub e} and ν{sub e} seen from the rotational axis of the MHD supernovae (i.e., polar direction), can be significantly different from those along the equatorial direction. The event numbers of ν-bar {sub e} observed from the polar direction are predicted to show steepest decrease, reflecting the passage of the magneto-driven shock to the so-called high-resonance regions. Furthermore we point out that such a shock effect, depending on the original neutrino spectra, appears also for the low-resonance regions, which could lead to a noticeable decrease in the ν{sub e} signals. This reflects a unique nature of the magnetic explosion featuring a very early shock-arrival to the resonance regions, which is in sharp contrast to the neutrino-driven delayed supernova models. Our results suggest that the two features in the ν-bar {sub e} and ν{sub e} signals, if visible to the Super-Kamiokande for a Galactic supernova, could mark an observational signature of the magnetically driven explosions, presumably linked to the formation of magnetars and/or long-duration gamma-ray bursts.

  11. Neutrino oscillations in MHD supernova explosions

    Energy Technology Data Exchange (ETDEWEB)

    Kawagoe, S; Kotake, K [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan); Takiwaki, T, E-mail: shio.k@nao.ac.j [Center for Computational Astrophysics, National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan)

    2010-01-01

    We calculate the neutrino oscillations numerically in magnetohydrodynamic (MHD) explosion models to see how asphericity has impacts on neutrino spectra. Magneto-driven explosions are one of the most attracting scenarios for producing large scale departures from spherical symmetric geometry, that are reported by many observational data. We find that the event rates at Super-Kamiokande (SK) seen from the polar direction (e.g., the rotational axis of the supernovae) decrease when the shock wave is propagating through H-resonance. In addition, we find that L-resonance in this situation becomes non-adiabatic, and the effect of L-resonance appears in the neutrino signal, because the MHD shock can propagate to the stellar surface without shock-stall after core bounce, and the shock reaches the L-resonance at earlier stage than the conventional spherical supernova explosion models. Our results suggest that we may obtain the observational signatures of the two resonances in SK for Galactic supernova.

  12. Radio evolution of supernova SN 2008iz in M 82

    Science.gov (United States)

    Kimani, N.; Sendlinger, K.; Brunthaler, A.; Menten, K. M.; Martí-Vidal, I.; Henkel, C.; Falcke, H.; Muxlow, T. W. B.; Beswick, R. J.; Bower, G. C.

    2016-08-01

    We report on multi-frequency Very Large Array (VLA) and Very Long Baseline Interferometry (VLBI) radio observations for a monitoring campaign of supernova SN 2008iz in the nearby irregular galaxy M 82. We fit two models to the data, a simple time power-law, S ∝ tβ, and a simplified Weiler model, yielding decline indices of β = -1.22 ± 0.07 (days 100-1500) and -1.41 ± 0.02 (days 76-2167), respectively. The late-time radio light-curve evolution shows flux-density flares at ~970 and ~1400 days that are a factor of ~2 and ~4 higher than the expected flux, respectively. The later flare, except for being brighter, does not show signs of decline at least from results examined so far (2014 January 23; day 2167). We derive the spectral index, α, S ∝ να for frequencies 1.4 to 43 GHz for SN 2008iz during the period from ~430 to 2167 days after the supernova explosion. The value of α shows no signs of evolution and remains steep ≈-1 throughout the period, unlike that of SN 1993J, which started flattening at ~day 970. From the 4.8 and 8.4 GHz VLBI images, the supernova expansion is seen to start with a shell-like structure that becomes increasingly more asymmetric, then breaks up in the later epochs, with bright structures dominating the southern part of the ring. This structural evolution differs significantly from SN 1993J, which remains circularly symmetric over 4000 days after the explosion. The VLBI 4.8 and 8.4 GHz images are used to derive a deceleration index, m, for SN 2008iz, of 0.86 ± 0.02, and the average expansion velocity between days 73 and 1400 as (12.1 ± 0.2) × 103 km s-1. From the energy equipartition between magnetic field and particles, we estimate the minimum total energy in relativistic particles and the magnetic fields during the supernova expansion and also find the magnetic field amplification factor for SN 2008iz to be in the range of 55-400. The VLBI images (FITS files) are only available at the CDS via anonymous ftp to http

  13. The evolution of the peculiar Type Ia supernova SN 2005hk over 400 days

    CERN Document Server

    Sahu, D K; Anupama, G C; Kawabata, Koji S; Maeda, Keiichi; Tominaga, Nozomu; Nomoto, Ken'ichi; Mazzali, Paolo A

    2007-01-01

    $UBVRI$ photometry and medium resolution optical spectroscopy of peculiar Type Ia supernova SN 2005hk are presented and analysed, covering the premaximum phase to around 400 days after explosion. The supernova is found to be underluminous compared to "normal" Type Ia supernovae. The photometric and spectroscopic evolution of SN 2005hk is remarkably similar to the peculiar Type Ia event SN 2002cx. The expansion velocity of the supernova ejecta is found to be lower than normal Type Ia events. The late time spectra of SN 2005hk do not show the presence of forbidden [\\ion{Fe}{ii}], [\\ion{Fe}{iii}] and [\\ion{Co}{iii}] lines, but are dominated by narrow, permitted \\ion{Fe}{ii}, NIR \\ion{Ca}{ii} and \\ion{Na}{i} lines with P-Cygni profiles. Light curve modeling indicates SN 2005hk to be a thermonuclear explosion with the Chandrasekhar mass ejecta, but with a smaller kinetic energy ($\\KE = 0.3 \\times 10^{51} {\\rm ergs}$) than that of canonical Type Ia supernovae. The mass of \\Nifs\\ synthesized in this explosion is $0....

  14. Type Ia Supernova Explosion: Gravitationally Confined Detonation

    CERN Document Server

    Plewa, T; Lamb, D

    2004-01-01

    We present a new mechanism for Type Ia supernova explosions in massive white dwarfs. The proposed scenario follows from relaxing the assumption of symmetry in the model and involves a detonation created in an unconfined environment. The explosion begins with an essentially central ignition of stellar material initiating a deflagration. This deflagration results in the formation of a buoyantly-driven bubble of hot material that reaches the stellar surface at supersonic speeds. The bubble breakout forms a strong pressure wave that laterally accelerates fuel-rich outer stellar layers. This material, confined by gravity to the white dwarf, races along the stellar surface and is focused at the location opposite to the point of the bubble breakout. These streams of nuclear fuel carry enough mass and energy to trigger a detonation just above the stellar surface. The flow conditions at that moment support a detonation that will incinerate the white dwarf and result in an energetic explosion. The stellar expansion fol...

  15. Phases of a Type Ia supernova explosion

    CERN Document Server

    Niemeyer, J C

    1998-01-01

    In the framework of the Chandrasekhar mass white dwarf model for Type Ia supernovae, various stages of the explosion are described in terms of the burning regimes of the thermonuclear flame front. In the early flamelet regime following the ``smoldering'' phase prior to the explosion, the flame is sufficiently thin and fast to remain laminar on small scales. As the white dwarf density declines, the thermal flame structure becomes subject to penetration by turbulent eddies, and it enters the ``distributed burning'' regime. A specific control parameter for this transition is proposed. Furthermore, we outline an argument for the coincidence of the transition between burning regimes with the onset of a deflagration-detonation-transition (DDT) in the late phase of the explosion.

  16. 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...

  17. Pre-explosion companion stars in Type Iax supernovae

    CERN Document Server

    Liu, Zheng-Wei; Abate, Carlo; Wang, Bo

    2015-01-01

    Type Iax supernovae (SNe Iax) are proposed as one new sub-class of SNe Ia since they present sufficiently distinct observational properties from the bulk of SNe Ia. SNe Iax are the most common of all types of peculiar SNe by both number and rate, with an estimated rate of occurrence of about 5-30% of the total SN Ia rate. However, the progenitor systems of SNe Iax are still uncertain. Analyzing pre-explosion images at SN Iax positions provides a direct way to place strong constraints on the nature of progenitor systems of SNe Iax. In this work, we predict pre-explosion properties of binary companion stars in a variety of potential progenitor systems by performing detailed binary evolution calculations with the one-dimensional stellar evolution code STARS. This will be helpful for constraining progenitor systems of SNe Iax from their pre-explosion observations. With our binary evolution calculations, it is found that the non-degenerate helium (He) companion star to both a massive C/O WD (> 1.1 solar mass) and ...

  18. A massive hypergiant star as the progenitor of the supernova SN 2005gl.

    Science.gov (United States)

    Gal-Yam, A; Leonard, D C

    2009-04-16

    Our understanding of the evolution of massive stars before their final explosions as supernovae is incomplete, from both an observational and a theoretical standpoint. A key missing piece in the supernova puzzle is the difficulty of identifying and studying progenitor stars. In only a single case-that of supernova SN 1987A in the Large Magellanic Cloud-has a star been detected at the supernova location before the explosion, and been subsequently shown to have vanished after the supernova event. The progenitor of SN 1987A was a blue supergiant, which required a rethink of stellar evolution models. The progenitor of supernova SN 2005gl was proposed to be an extremely luminous object, but the association was not robustly established (it was not even clear that the putative progenitor was a single luminous star). Here we report that the previously proposed object was indeed the progenitor star of SN 2005gl. This very massive star was likely a luminous blue variable that standard stellar evolution predicts should not have exploded in that state.

  19. Explosion Calculations of SN1087

    Science.gov (United States)

    Wooden, Diane H.; Morrison, David (Technical Monitor)

    1994-01-01

    Explosion calculations of SNT1987A generate pictures of Rayleigh-Taylor fingers of radioactive Ni-56 which are boosted to velocities of several thousand km/s. From the KAO observations of the mid-IR iron lines, a picture of the iron in the ejecta emerges which is consistent with the "frothy iron fingers" having expanded to fill about 50% of the metal-rich volume of the ejecta. The ratio of the nickel line intensities yields a high ionization fraction of greater than or equal to 0.9 in the volume associated with the iron-group elements at day 415, before dust condenses in the ejecta. From the KAO observations of the dust's thermal emission, it is deduced that when the grains condense their infrared radiation is trapped, their apparent opacity is gray, and they have a surface area filling factor of about 50%. The dust emission from SN1987A is featureless: no 9.7 micrometer silicate feature, nor PAH features, nor dust emission features of any kind are seen at any time. The total dust opacity increases with time even though the surface area filling factor and the dust/gas ratio remain constant. This suggests that the dust forms along coherent structures which can maintain their radial line-of-sight opacities, i.e., along fat fingers. The coincidence of the filling factor of the dust and the filling factor of the iron strongly suggests that the dust condenses within the iron, and therefore the dust is iron-rich. It only takes approximately 4 x 10(exp -4) solar mass of dust for the ejecta to be optically thick out to approximately 100 micrometers; a lower limit of 4 x 10(exp -4) solar mass of condensed grains exists in the metal-rich volume, but much more dust could be present. The episode of dust formation started at about 530 days and proceeded rapidly, so that by 600 days 45% of the bolometric luminosity was being emitted in the IR; by 775 days, 86% of the bolometric luminosity was being reradiated by the dust. Measurements of the bolometric luminosity of SN1987A from

  20. CONSTRAINING TYPE Ia SUPERNOVA MODELS: SN 2011fe AS A TEST CASE

    Energy Technology Data Exchange (ETDEWEB)

    Roepke, F. K.; Seitenzahl, I. R. [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, Am Hubland, D-97074 Wuerzburg (Germany); Kromer, M.; Taubenberger, S.; Ciaraldi-Schoolmann, F.; Hillebrandt, W.; Benitez-Herrera, S. [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Pakmor, R. [Heidelberger Institut fuer Theoretische Studien, Schloss-Wolfsbrunnenweg 35, 69118 Heidelberg (Germany); Sim, S. A. [Research School of Astronomy and Astrophysics, Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611 (Australia); Aldering, G.; Childress, M.; Fakhouri, H. K. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F. [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. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, 53115 Bonn (Germany); Chotard, N.; Copin, Y. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others

    2012-05-01

    The nearby supernova SN 2011fe can be observed in unprecedented detail. Therefore, it is an important test case for Type Ia supernova (SN Ia) models, which may bring us closer to understanding the physical nature of these objects. Here, we explore how available and expected future observations of SN 2011fe can be used to constrain SN Ia explosion scenarios. We base our discussion on three-dimensional simulations of a delayed detonation in a Chandrasekhar-mass white dwarf and of a violent merger of two white dwarfs (WDs)-realizations of explosion models appropriate for two of the most widely discussed progenitor channels that may give rise to SNe Ia. Although both models have their shortcomings in reproducing details of the early and near-maximum spectra of SN 2011fe obtained by the Nearby Supernova Factory (SNfactory), the overall match with the observations is reasonable. The level of agreement is slightly better for the merger, in particular around maximum, but a clear preference for one model over the other is still not justified. Observations at late epochs, however, hold promise for discriminating the explosion scenarios in a straightforward way, as a nucleosynthesis effect leads to differences in the {sup 55}Co production. SN 2011fe is close enough to be followed sufficiently long to study this effect.

  1. Early Radio and X-Ray Observations of the Youngest nearby Type Ia Supernova PTF 11kly (SN 2011fe)

    NARCIS (Netherlands)

    Horesh, Assaf; Kulkarni, S. R.; Fox, Derek B.; Carpenter, John; Kasliwal, Mansi M.; Ofek, Eran O.; Quimby, Robert; Gal-Yam, Avishay; Cenko, Bradley; de Bruyn, A. G.; Kamble, Atish; Wijers, Ralph A. M. J.; van der Horst, Alexander J.; Kouveliotou, Chryssa; Podsiadlowski, Philipp; Sullivan, Mark; Maguire, Kate; Howell, D. Andrew; Nugent, Peter E.; Gehrels, Neil; Law, Nicholas M.; Poznanski, Dovi; Shara, Michael

    2012-01-01

    On 2011 August 24 (UT) the Palomar Transient Factory (PTF) discovered PTF11kly (SN 2011fe), the youngest and most nearby Type Ia supernova (SN Ia) in decades. We followed this event up in the radio (centimeter and millimeter bands) and X-ray bands, starting about a day after the estimated explosion

  2. 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...

  3. How supernova explosions power galactic winds

    CERN Document Server

    Creasey, Peter; Bower, Richard G

    2012-01-01

    Feedback from supernovae is an essential aspect of galaxy formation. In order to improve subgrid models of feedback we perform a series of numerical experiments to investigate how supernova explosions power galactic winds. We use the Flash hydrodynamic code to model a simplified ISM, including gravity, hydrodynamics, radiative cooling above 10,000 K, and star formation that reproduces the Kennicutt-Schmidt relation. By simulating a small patch of the ISM in a tall box perpendicular to the disk, we obtain sub-parsec resolution allowing us to resolve individual supernova events and we investigate how the wind properties depend on those of the ISM and the galaxy. We find that outflows are more efficient in disks with lower surface densities or gas fractions. A simple model in which the warm cloudy medium is the barrier that limits the expansion of blast waves reproduces the scaling of outflow properties with disk parameters at high star formation rates. The scaling we find sets the investigation of galaxy winds ...

  4. 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.

  5. 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.

  6. 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.

  7. On the Nature of Core-Collapse Supernova Explosions

    Science.gov (United States)

    Burrows, Adam; Hayes, John; Fryxell, Bruce A.

    1995-09-01

    bound. In addition, for a given asymptotic explosion energy, the amount of mass that reaches explosive nucleosynthesis temperatures is less than heretofore assumed. This may help to solve the 56Ni overproduction problem encountered in previous models of explosive nucleosynthesis. The high-speed fingers that emerge from our model core seem a natural explanation for the nickel bullets seen in SN 1987A and the shrapnel inferred in some supernova remnants. In addition, the vigorous convective motions interior to the shock can impart to the residue recoil velocities and spins. The magnitudes of the former might be within reach of the observed pulsar proper motions, but extensive new calculations remain to be done to verify this. Within 100 ms of the explosion, a strong, neutrino-driven wind is blowing outward from the proto neutron star that clears the interior of mass and, while operative, does not allow fallback. At the base of the rising explosion plumes (in the early wind), a few high-entropy (˜60) clumps are ejected, whose subsequent evolution may prove to be of relevance to the r-process.

  8. Tycho Brahe's 1572 supernova as a standard type Ia explosion revealed from its light echo spectrum

    CERN Document Server

    Krause, Oliver; Usuda, Tomonori; Hattori, Takashi; Goto, Miwa; Birkmann, Stephan; Nomoto, Ken'ichi

    2008-01-01

    Type Ia supernovae (SNe Ia) are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions are how the explosion actually proceeds and whether accretion occurs from a companion or via the merging of two white dwarfs. Tycho Brahe's supernova of 1572 (SN 1572) is thought to be one of the best candidates for a SN Ia in the Milky Way. The proximity of the SN 1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. The determination of the yet unknown exact spectroscopic type of SN 1572 is crucial to relate these results to the diverse population of SNe Ia. Here we report an optical spectrum of Tycho Brahe's supernova near maximum brightness, obtained from a scatter...

  9. The High-Metallicity Explosion Environment of the Relativistic Supernova 2009bb

    CERN Document Server

    Levesque, E M; Foley, R J; Berger, E; Kewley, L J; Chakraborty, S; Ray, A; Torres, M A P; Challis, P; Kirshner, R P; Barthelmy, S D; Bietenholz, M F; Chandra, P; Chaplin, V; Chevalier, R A; Chugai, N; Connaughton, V; Copete, A; Fox, O; Fransson, C; Grindlay, J E; Hamuy, M A; Milne, P A; Pignata, G; Stritzinger, M D; Wieringa, M H

    2009-01-01

    We investigate the environment of the nearby (d ~ 40Mpc) broad-lined Type Ic supernova SN 2009bb. This event was observed to produce a relativistic outflow likely powered by a central accreting compact object. While such a phenomenon was previously observed only in long-duration gamma-ray bursts (LGRBs), no LGRB was detected in association with SN 2009bb. Using an optical spectrum of the SN 2009bb explosion site, we determine a variety of ISM properties for the host environment, including metallicity, young stellar population age, and star formation rate. We compare the SN explosion site properties to observations of LGRB and broad-lined SN Ic host environments on optical emission line ratio diagnostic diagrams. Based on these analyses, we find that the SN 2009bb explosion site has a very high metallicity of ~2x solar, in agreement with other broad-lined SN Ic host environments and at odds with the low-redshift LGRB host environments and recently proposed maximum metallicity limits for relativistic explosions...

  10. Integral field spectroscopy of supernova explosion sites: constraining mass and metallicity of the progenitors - I. Type Ib and Ic supernovae

    CERN Document Server

    Kuncarayakti, Hanindyo; Aldering, Greg; Arimoto, Nobuo; Maeda, Keiichi; Morokuma, Tomoki; Pereira, Rui; Usuda, Tomonori; Hashiba, Yasuhito

    2013-01-01

    Integral field spectroscopy of 11 type-Ib/c supernova explosion sites in nearby galaxies has been obtained using UH88/SNIFS and Gemini-N/GMOS. The use of integral field spectroscopy enables us to obtain both spatial and spectral information of the explosion site, allowing the identification of the parent stellar population of the supernova progenitor star. The spectrum of the parent population provides metallicity determination via strong-line method and age estimation obtained via comparison with simple stellar population (SSP) models. We adopt this information as the metallicity and age of the supernova progenitor, under the assumption that it was coeval with the parent stellar population. The age of the star corresponds to its lifetime, which in turn gives the estimate of its initial mass. With this method we were able to determine both the metallicity and initial (ZAMS) mass of the progenitor stars of the type Ib and Ic supernovae. We found that on average SN Ic explosion sites are more metal-rich and you...

  11. SN 2005ap: A Most Brilliant Explosion

    CERN Document Server

    Quimby, Robert M; Wheeler, J Craig; Höflich, Peter; Akerlof, Carl W; Rykoff, Eli S

    2007-01-01

    We present unfiltered photometric observations with ROTSE-III and optical spectroscopic follow-up with the HET and Keck of the most luminous supernova yet identified, SN 2005ap. The spectra taken about 3 days before and 6 days after maximum light show narrow emission lines (likely originating in the dwarf host) and absorption lines at a redshift of z=0.2832, which puts the peak unfiltered magnitude at -22.7 +/- 0.1 absolute. Broad P-Cygni features corresponding to H-alpha, CIII, NIII, and OIII, are further detected with a photospheric velocity of ~20,000 km/s. Unlike other highly luminous supernovae such as 2006gy and 2006tf that show slow photometric evolution, the light curve of SN 2005ap indicates a 1-3 week rise to peak followed by a relatively rapid decay. The spectra also lack the distinct emission peaks from moderately broadened (FWHM ~ 2,000 km/s) Balmer lines seen in SN 2006gy and SN 2006tf. We briefly discuss the origin of the extraordinary luminosity from a strong interaction as may be expected fro...

  12. THE IMPACT OF TYPE Ia SUPERNOVA EXPLOSIONS ON HELIUM COMPANIONS IN THE CHANDRASEKHAR-MASS EXPLOSION SCENARIO

    Energy Technology Data Exchange (ETDEWEB)

    Liu Zhengwei; Wang, B.; Han, Z. W. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Pakmor, R. [Heidelberger Institut fuer Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Seitenzahl, I. R.; Hillebrandt, W.; Kromer, M.; Edelmann, P.; Taubenberger, S. [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Roepke, F. K. [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, Am Hubland, D-97074 Wuerzburg (Germany); Maeda, K., E-mail: zwliu@ynao.ac.cn [Kavli Institute for the Physics and Mathematics of the Universe (Kavli-IPMU), Todai Institutes for Advanced Study (TODIAS), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)

    2013-09-01

    In the version of the single-degenerate scenario of Type Ia supernovae (SNe Ia) studied here, a carbon-oxygen white dwarf explodes close to the Chandrasekhar limit after accreting material from a non-degenerate helium (He) companion star. In the present study, we employ the STELLAR GADGET code to perform three-dimensional hydrodynamical simulations of the interaction of the SN Ia ejecta with the He companion star taking into account its orbital motion and spin. It is found that only 2%-5% of the initial companion mass is stripped off from the outer layers of He companion stars due to the supernova (SN) impact. The dependence of the unbound mass (or the kick velocity) on the orbital separation can be fitted to a good approximation by a power law for a given companion model. After the SN impact, the outer layers of a He donor star are significantly enriched with heavy elements from the low-expansion-velocity tail of SN Ia ejecta. The total mass of accumulated SN-ejecta material on the companion surface reaches about {approx}> 10{sup -3} M{sub Sun} for different companion models. This enrichment with heavy elements provides a potential way to observationally identify the surviving companion star in SN remnants. Finally, by artificially adjusting the explosion energy of the W7 explosion model, we find that the total accumulation of SN ejecta on the companion surface is also dependent on the explosion energy with a power-law relation to a good approximation.

  13. A LUMINOUS AND FAST-EXPANDING TYPE Ib SUPERNOVA SN 2012au

    Energy Technology Data Exchange (ETDEWEB)

    Takaki, Katsutoshi; Fukazawa, Yasushi; Itoh, Ryosuke; Ueno, Issei; Ui, Takahiro; Urano, Takeshi [Department of Physical Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Kawabata, Koji S.; Akitaya, Hiroshi; Moritani, Yuki; Ohsugi, Takashi; Uemura, Makoto; Yoshida, Michitoshi [Hiroshima Astrophysical Science Center, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Yamanaka, Masayuki [Kwasan Observatory, Kyoto University, Ohmine-cho Kita Kazan, Yamashina-ku, Kyoto 607-8471 (Japan); Maeda, Keiichi; Nomoto, Ken' ichi [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Tanaka, Masaomi [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Kinugasa, Kenzo [Nobeyama Radio Observatory, National Astronomical Observatory of Japan, 462-2 Nobeyama, Minamimaki, Nagano 384-1305 (Japan); Sasada, Mahito, E-mail: takaki@hep01.hepl.hiroshima-u.ac.jp [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)

    2013-08-01

    We present a set of photometric and spectroscopic observations of a bright Type Ib supernova SN 2012au from -6 days until {approx} + 150 days after maximum. The shape of its early R-band light curve is similar to that of an average Type Ib/c supernova. The peak absolute magnitude is M{sub R} = -18.7 {+-} 0.2 mag, which suggests that this supernova belongs to a very luminous group among Type Ib supernovae. The line velocity of He I {lambda}5876 is about 15,000 km s{sup -1} around maximum, which is much faster than that in a typical Type Ib supernova. From the quasi-bolometric peak luminosity of (6.7 {+-} 1.3) Multiplication-Sign 10{sup 42} erg s{sup -1}, we estimate the {sup 56}Ni mass produced during the explosion as {approx}0.30 M{sub Sun }. We also give a rough constraint to the ejecta mass 5-7 M{sub Sun} and the kinetic energy (7-18) Multiplication-Sign 10{sup 51} erg. We find a weak correlation between the peak absolute magnitude and He I velocity among Type Ib SNe. The similarities to SN 1998bw in the density structure inferred from the light-curve model as well as the large peak bolometric luminosity suggest that SN 2012au had properties similar to energetic Type Ic supernovae.

  14. Constraining Type Ia supernova models: SN 2011fe as a test case

    CERN Document Server

    Roepke, F K; Seitenzahl, I R; Pakmor, R; Sim, S A; Taubenberger, S; Ciaraldi-Schoolmann, F; Hillebrandt, W; Aldering, G; Antilogus, P; Baltay, C; Benitez-Herrera, S; Bongard, S; Buton, C; Canto, A; Cellier-Holzem, F; Childress, M; Chotard, N; Copin, Y; Fakhouri, H K; Fink, M; Fouchez, D; Gangler, E; Guy, J; Hachinger, S; Hsiao, E Y; Juncheng, C; Kerschhaggl, M; Kowalski, M; Nugent, P; Paech, K; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigault, M; Runge, K; Saunders, C; Smadja, G; Suzuki, N; Tao, C; Thomas, R C; Tilquin, A; Wu, C

    2012-01-01

    The nearby supernova SN 2011fe can be observed in unprecedented detail. Therefore, it is an important test case for Type Ia supernova (SN Ia) models, which may bring us closer to understanding the physical nature of these objects. Here, we explore how available and expected future observations of SN 2011fe can be used to constrain SN Ia explosion scenarios. We base our discussion on three-dimensional simulations of a delayed detonation in a Chandrasekhar-mass white dwarf and of a violent merger of two white dwarfs-realizations of explosion models appropriate for two of the most widely-discussed progenitor channels that may give rise to SNe Ia. Although both models have their shortcomings in reproducing details of the early and near-maximum spectra of SN 2011fe obtained by the Nearby Supernova Factory (SNfactory), the overall match with the observations is reasonable. The level of agreement is slightly better for the merger, in particular around maximum, but a clear preference for one model over the other is s...

  15. Observation and interpretation of type IIb supernova explosions

    Science.gov (United States)

    Morales-Garoffolo, Antonia

    2016-03-01

    Core-collapse supernovae (CC-SNe) explosions represent the final demise of massive stars. Among the various types, there is a group of relatively infrequent CC-SNe termed type IIb, which appear to be hybrids between normal type II SNe (those characterised by H emission) and type Ib (those that lack H features in their spectra but exhibit prominent HeI lines). The nature of the stellar progenitors leading to type IIb SNe is currently unknown, although two channels are contemplated: single massive stars that have lost part of their outer envelope as a consequence of stellar winds, and massive stars that shed mass by Roche-Lobe overflow to a companion. The latter is in fact the favoured scenario for most of the objects observed up to now. In the majority of cases, when there are no direct progenitor detections, some hints about type IIb SN progenitors (e.g., initial mass) can be derived indirectly from the objects' light curves (LCs) and spectra. Motivated by the relatively few well-sampled observational datasets that exist up to date for type IIb SNe and the unknowns on their progenitors, we carried out extensive observations (mainly in the optical domain) for the young type IIb SNe 2011fu and 2013df. Both these SNe are particularly interesting because they show a first LC peak caused by shock breakout, followed by a secondary 56Ni-decay-powered maximum. The analysis of the data for SNe 2011fu and 2013df points to precursors that seem to have been stars with large radii (of the order of 100 RSun), with low mass hydrogen envelopes (tenths of MSun), and relatively low initial masses (12-18 MSun), which could have formed part of interacting binary systems. The nature of a third SN IIb candidate, OGLE-2013-SN-100, proved to be enigmatic. OGLE-2013-SN-100, shows a first peak in the LC, and other characteristics somewhat similar to those of type IIb SNe. However, after a deeper analysis, we conclude OGLE-2013-SN-100 is likely not a SN of type IIb. We provide an alternative

  16. Early 56Ni decay {\\gamma}-rays from SN2014J suggest an unusual explosion

    CERN Document Server

    Diehl, Roland; Hillebrandt, Wolfgang; Grebenev, Sergei A; Greiner, Jochen; Krause, Martin; Kromer, Markus; Maeda, Keiichi; Roepke, Friedrich; Taubenberger, Stefan

    2014-01-01

    Type-Ia supernovae result from binary systems that include a carbon-oxygen white dwarf, and these thermonuclear explosions typically produce 0.5 M_solar of radioactive 56Ni. The 56Ni is commonly believed to be buried deeply in the expanding supernova cloud. Surprisingly, in SN2014J we detected the lines at 158 and 812 keV from 56Ni decay ({\\tau}~8.8 days) earlier than the expected several-week time scale, only ~20 days after the explosion, and with flux levels corresponding to roughly 10% of the total expected amount of 56Ni. Some mechanism must break the spherical symmetry of the supernova, and at the same time create a major amount of 56Ni at the outskirts. A plausible explanation is that a belt of helium from the companion star is accreted by the white dwarf, where this material explodes and then triggers the supernova event.

  17. Radioactive Iron Rain: Evidence of a Nearby Supernova Explosion

    CERN Document Server

    CERN. Geneva

    2016-01-01

    A very close supernova explosion could have caused a mass extinction of life in Earth. In 1996, Brian Fields, the late Dave Schramm and the speaker proposed looking for unstable isotopes such as Iron 60 that could have been deposited by a recent nearby supernova explosion. A group from the Technical University of Munich has discovered Iron 60 in deep-ocean sediments and ferromanganese crusts due to one or more supernovae that exploded O(100) parsecs away about 2.5 million years ago. These results have recently been confirmed by a group from the Australian National University, and the Munich group has also discovered supernova Iron 60 in lunar rock samples. This talk will discuss the interpretation of these results in terms of supernova models, and the possible implications for life on Earth.

  18. Integral field spectroscopy of supernova explosion sites: constraining mass and metallicity of the progenitors -- II. Type II-P and II-L supernovae

    CERN Document Server

    Kuncarayakti, Hanindyo; Aldering, Greg; Arimoto, Nobuo; Maeda, Keiichi; Morokuma, Tomoki; Pereira, Rui; Usuda, Tomonori; Hashiba, Yasuhito

    2013-01-01

    Thirteen explosion sites of type II-P and II-L supernovae in nearby galaxies have been observed using integral field spectroscopy, enabling both spatial and spectral study of the explosion sites. We used the properties of the parent stellar population of the coeval supernova progenitor star to derive its metallicity and initial mass (c.f. Paper I). The spectrum of the parent stellar population yields the estimates of metallicity via strong-line method, and age via comparison with simple stellar population (SSP) models. These metallicity and age parameters are adopted for the progenitor star. Age, or lifetime of the star, was used to derive initial (ZAMS) mass of the star by comparing with stellar evolution models. With this technique, we were able to determine metallicity and initial mass of the SN progenitors in our sample. Our result indicates that some type-II supernova progenitors may have been stars with mass comparable to SN Ib/c progenitors.

  19. Spectrophotometric time series of SN 2011fe from the Nearby Supernova Factory

    CERN Document Server

    Pereira, R; Aldering, G; Antilogus, P; Baltay, C; Benitez-Herrera, S; Bongard, S; Buton, C; Canto, A; Cellier-Holzem, F; Chen, J; Childress, M; Chotard, N; Copin, Y; Fakhouri, H K; Fink, M; Fouchez, D; Gangler, E; Guy, J; Hillebrandt, W; Hsiao, E Y; Kerschhaggl, M; Kowalski, M; Kromer, M; Nordin, J; Nugent, P; Paech, K; Pain, R; Pécontal, E; Perlmutter, S; Rabinowitz, D; Rigault, M; Runge, K; Saunders, C; Smadja, G; Tao, C; Taubenberger, S; Tilquin, A; Wu, C

    2013-01-01

    We present 32 epochs of optical (3300-9700 \\AA) spectrophotometric observations of the nearby quintessential "normal" type Ia supernova (SN Ia) SN 2011fe in the galaxy M101, extending from -15 to +97 d with respect to B-band maximum, obtained by the Nearby Supernova Factory collaboration. SN 2011fe is the closest (\\mu = 29.04) and brightest (Bmax = 9.94 mag) SN Ia observed since the advent of modern large scale programs for the intensive periodic followup of supernovae. Both synthetic light curve measurements and spectral feature analysis attest to the normality of SN 2011fe. There is very little evidence for reddening in its host galaxy. The homogeneous calibration, intensive time sampling, and high signal-to-noise ratio of the data set make it unique. Thus it is ideal for studying the physics of SN Ia explosions in detail, and for furthering the use of SNe Ia as standardizable candles for cosmology. Several such applications are shown, from the creation of a bolometric light curve and measurement of the 56N...

  20. A distorted radio shell in the young supernova SN1986J

    CERN Document Server

    Pérez-Torres, M A; Marcaide, J M; Guirado, J C; Lara, L; Mantovani, F; Ros, E; Weiler, K W

    2002-01-01

    We report 5 GHz global very-long-baseline interferometry observations of SN1986J, 16 yr after its explosion. We obtained a high-resolution image of the supernova, which shows a distorted shell of radio emission, indicative of a deformation of the shock front. The average speed of the shell has decreased from ~7600 km/s in 1988.74 down to about 6300 km/s in 1999.14, indicative of a mild deceleration in the expansion of SN1986J. Assuming a standard density profile for the progenitor wind, we obtain a swept-up mass by the shock front of ~2.2 solar masses. This large swept-up mass, coupled with the mild deceleration suffered by the supernova, suggests that the mass of the hydrogen-rich envelope ejected at explosion was >= 12 solar masses. Thus, the supernova progenitor must have kept intact most of its hydrogen-rich envelope by the time of explosion, which favours a single, massive star progenitor scenario. We find a flux density for SN 1986J of ~7.2 mJy at the observing frequency of 5 GHz, which results in a rad...

  1. 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...

  2. INTERACTING SUPERNOVAE AND SUPERNOVA IMPOSTORS: SN 2009ip, IS THIS THE END?

    Energy Technology Data Exchange (ETDEWEB)

    Pastorello, A.; Cappellaro, E.; Benetti, S. [INAF-Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Inserra, C.; Smartt, S. J.; Fraser, M. [Astrophysics Research Centre, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom); Pignata, G.; Takats, K.; Bufano, F. [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Valenti, S. [Las Cumbres Observatory Global Telescope Network Inc., Santa Barbara, CA 93117 (United States); Benitez, S. [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Botticella, M. T. [INAF-Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, I-80131 Napoli (Italy); Brimacombe, J. [Coral Towers Observatory, Coral Towers, Esplanade, Cairns 4870 (Australia); Cellier-Holzem, F. [Laboratoire de Physique Nucleaire et de Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot, Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Costado, M. T. [Instituto de Astrofisica de Andalucia, CSIC, Apdo 3004, E-18080 Granada (Spain); Cupani, G. [INAF-Osservatorio Astronomico di Trieste, via Tiepolo 11, I-34143 Trieste (Italy); Curtis, I. [2 Yandra Street, Vale Park, Adelaide, South Australia 5081 (Australia); Elias-Rosa, N. [Institut de Ciencies de l' Espai (IEEC-CSIC), Campus UAB, E-08193 Bellaterra (Spain); Ergon, M. [The Oskar Klein Centre, Department of Astronomy, AlbaNova, Stockholm University, SE-106 91 Stockholm (Sweden); Fynbo, J. P. U., E-mail: andrea.pastorello@oapd.inaf.it [Dark Cosmology Centre, Niels Bohr Institute, Copenhagen University, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark); and others

    2013-04-10

    We report the results of a three-year-long dedicated monitoring campaign of a restless luminous blue variable (LBV) in NGC 7259. The object, named SN 2009ip, was observed photometrically and spectroscopically in the optical and near-infrared domains. We monitored a number of erupting episodes in the past few years, and increased the density of our observations during eruptive episodes. In this paper, we present the full historical data set from 2009 to 2012 with multi-wavelength dense coverage of the two high-luminosity events between 2012 August and September. We construct bolometric light curves and measure the total luminosities of these eruptive or explosive events. We label them the 2012a event (lasting {approx}50 days) with a peak of 3 Multiplication-Sign 10{sup 41} erg s{sup -1}, and the 2012b event (14 day rise time, still ongoing) with a peak of 8 Multiplication-Sign 10{sup 42} erg s{sup -1}. The latter event reached an absolute R-band magnitude of about -18, comparable to that of a core-collapse supernova (SN). Our historical monitoring has detected high-velocity spectral features ({approx}13,000 km s{sup -1}) in 2011 September, one year before the current SN-like event. This implies that the detection of such high-velocity outflows cannot, conclusively, point to a core-collapse SN origin. We suggest that the initial peak in the 2012a event was unlikely to be due to a faint core-collapse SN. We propose that the high intrinsic luminosity of the latest peak, the variability history of SN 2009ip, and the detection of broad spectral lines indicative of high-velocity ejecta are consistent with a pulsational pair-instability event, and that the star may have survived the last outburst. The question of the survival of the LBV progenitor star and its future fate remain open issues, only to be answered with future monitoring of this historically unique explosion.

  3. 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.

  4. A Luminous and Fast-Expanding Type Ib Supernova SN 2012au

    CERN Document Server

    Takaki, K; Yamanaka, M; Maeda, K; Tanaka, M; Akitaya, H; Fukazawa, Y; Itoh, R; Kinugasa, K; Moritani, Y; Ohsugi, T; Sasada, M; Uemura, M; Ueno, I; Ui, T; Urano, T; Yoshida, M; Nomoto, K

    2013-01-01

    We present a set of photometric and spectroscopic observations of a bright Type Ib supernova SN 2012au from -6d until ~+150d after maximum. The shape of its early R-band light curve is similar to that of an average Type Ib/c supernova. The peak absolute magnitude is M_R=-18.7+-0.2 mag, which suggests that this supernova belongs to a very luminous group among Type Ib supernovae. The line velocity of He I {\\lambda}5876 is about 15,000 km/s around maximum, which is much faster than that in a typical Type Ib supernova. From the quasi-bolometric peak luminosity of (6.7+-1.3)x10^(42) erg/s, we estimate the \\Ni mass produced during the explosion as ~0.30 Msun. We also give a rough constraint to the ejecta mass 5-7 Msun and the kinetic energy (7-18)x10^(51) erg. We find a weak correlation between the peak absolute magnitude and He I velocity among Type Ib SNe. The similarities to SN 1998bw in the density structure inferred from the light curve model as well as the large peak bolometric luminosity suggest that SN 2012...

  5. Constraining supernova progenitors: an integral field spectroscopic survey of the explosion sites

    CERN Document Server

    Kuncarayakti, H; Anderson, J P; Arimoto, N; Doi, M; Galbany, L; Hamuy, M; Hashiba, Y; Kruehler, T; Maeda, K; Morokuma, T; Usuda, T

    2014-01-01

    We describe a survey of nearby core-collapse supernova (SN) explosion sites using integral field spectroscopy (IFS) technique, which is an extension of the work described in Kuncarayakti et al. (2013, AJ, 146, 30/31) . The project aims to constrain the SN progenitor properties based on the study of the SN immediate environment. The stellar populations present at the SN explosion sites are studied by means of integral field spectroscopy, which enables the acquisition of both spatial and spectral information of the object simultaneously. The spectrum of the SN parent stellar population gives the estimate of its age and metallicity. With this information, the initial mass and metallicity of the once coeval SN progenitor star are derived. While the survey is mostly done in optical, additionally the utilization of near-infrared integral field spectroscopy assisted with adaptive optics (AO) enables us to examine the explosion sites in high spatial details, down to a few parsecs. This work is being carried out using...

  6. Nearby Supernova Factory Observations of SN 2006D: On Sporadic Carbon Signatures in Early Type Ia Supernova Spectra

    CERN Document Server

    Factory, T N S; Aldering, G; Antilogus, P; Aragon, C; Bailey, S; Baltay, C; Baron, E; Bauer, A; Buton, C; Bongard, S; Copin, Y; Gangler, E; Gilles, S; Kessler, R; Loken, S; Nugent, P; Pain, R; Parrent, J; Pécontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigaudier, G; Runge, K; Scalzo, R; Smadja, G; Wang, L; Weaver, B A; Factory, The Nearby Supernova

    2006-01-01

    We present four spectra of the Type Ia supernova (SN Ia) 2006D extending from -7 to +13 days with respect to B-band maximum. The spectra include the strongest signature of unburned material at photospheric velocities observed in a SN Ia to date. The earliest spectrum exhibits C II absorption features below 14,000 km/s, including a distinctive C II \\lambda 6580 absorption feature. The carbon signatures dissipate as the SN approaches peak brightness. In addition to discussing implications of photospheric-velocity carbon for white dwarf explosion models, we outline some factors that may influence the frequency of its detection before and around peak brightness. Two effects are explored in this regard, including depopulation of the C II optical levels by non-LTE effects, and line-of-sight effects resulting from a clumpy distribution of unburned material with low volume-filling factor.

  7. SN 2010LP—A TYPE IA SUPERNOVA FROM A VIOLENT MERGER OF TWO CARBON-OXYGEN WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Kromer, M.; Taubenberger, S.; Seitenzahl, I. R.; Hillebrandt, W. [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany); Pakmor, R. [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Pignata, G. [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Fink, M.; Röpke, F. K. [Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Emil-Fischer-Str. 31, D-97074 Würzburg (Germany); Sim, S. A. [Astrophysics Research Centre, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom)

    2013-11-20

    SN 2010lp is a subluminous Type Ia supernova (SN Ia) with slowly evolving lightcurves. Moreover, it is the only subluminous SN Ia observed so far that shows narrow emission lines of [O I] in late-time spectra, indicating unburned oxygen close to the center of the ejecta. Most explosion models for SNe Ia cannot explain the narrow [O I] emission. Here, we present hydrodynamic explosion and radiative transfer calculations showing that the violent merger of two carbon-oxygen white dwarfs of 0.9 and 0.76 M {sub ☉} adequately reproduces the early-time observables of SN 2010lp. Moreover, our model predicts oxygen close to the center of the explosion ejecta, a pre-requisite for narrow [O I] emission in nebular spectra as observed in SN 2010lp.

  8. A Simple Approach to the Supernova Progenitor-Explosion Connection

    CERN Document Server

    Müller, B; Liptai, D; Cameron, J B

    2016-01-01

    We present a new approach to understand the landscape of supernova explosion energies, ejected nickel masses, and neutron star birth masses. In contrast to other recent parametric approaches, our model predicts the properties of neutrino-driven explosions based on the pre-collapse stellar structure without the need for hydrodynamic simulations. The model is based on physically motivated scaling laws and simple differential equations describing the shock propagation, the contraction of the neutron star, the neutrino emission, the heating conditions, and the explosion energetics. Using model parameters compatible with multi-D simulations and a fine grid of thousands of supernova progenitors, we obtain a variegated landscape of neutron star and black hole formation similar to other parameterised approaches and find good agreement with semi-empirical measures for the "explodability" of massive stars. Our predicted explosion properties largely conform to observed correlations between the nickel mass and explosion ...

  9. Core collapse supernovae from blue supergiant progenitors : The evolutionary history of SN 1987A

    Science.gov (United States)

    Menon, Athira

    2015-08-01

    SN 1987A is historically one of the most remarkable supernova explosions to be seen from Earth. Due to the proximity of its location in the LMC, it remains the most well-studied object outside the solar system. It was also the only supernova whose progenitor was observed prior to its explosion.SN 1987A however, was a unique and enigmatic core collapse supernova. It was the first Type II supernova to have been observed to have exploded while its progenitor was a blue supergiant (BSG). Until then Type II supernovae were expected to originate from explosions of red supergiants (RSGs). A spectacular triple-ring nebula structure, rich in helium and nitrogen, was observed around the remnant, indicating a recent RSG phase before becoming a BSG. Even today it is not entirely understood what the evolutionary history may have been to cause a BSG to explode. The most commonly accepted hypothesis for its origin is the merger of a massive binary star system.An evolutionary scenario for such a binary system, was proposed by Podsiadlowski (1992) (P92). Through SPH simulations of the merger and the stellar evolution of the post-merger remnant, Ivanova & Podsiadlowski (2002) and (2003) (I&M) could successfully obtain the RSG to BSG transition of the progenitor.The aim of the present work is to produce the evolutionary history of the progenitor of SN 1987A and its explosion. We construct our models based on the results of P92 and I&M. Here, the secondary (less massive) star is accreted on the primary, while being simultaneously mixed in its envelope over a period of 100 years. The merged star is evolved until the onset of core collapse. For this work we use the 1-dimensional, implicit, hydrodynamical stellar evolution code, KEPLER. A large parameter space is explored, consisting of primary (16-20 Ms) and secondary masses (5-8 Ms), mixing boundaries, and accreting timescales. Those models whose end states match the observed properties of the progenitor of SN 1987A are exploded. The

  10. TYPE Iax SUPERNOVAE: A NEW CLASS OF STELLAR EXPLOSION

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Ryan J.; Challis, P. J.; Chornock, R.; Marion, G. H.; Kirshner, R. P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Ganeshalingam, M.; Li, W.; Silverman, J. M.; Filippenko, A. V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Morrell, N. I.; Phillips, M. M. [Carnegie Observatories, Las Campanas Observatory, La Serena (Chile); Pignata, G. [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Stritzinger, M. D. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, DK-8000 Aarhus C (Denmark); Wang, X. [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Anderson, J. P.; Hamuy, M. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Freedman, W. L.; Persson, S. E. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Jha, S. W.; McCully, C., E-mail: rfoley@cfa.harvard.edu [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); and others

    2013-04-10

    We describe observed properties of the Type Iax class of supernovae (SNe Iax), consisting of SNe observationally similar to its prototypical member, SN 2002cx. The class currently has 25 members, and we present optical photometry and/or optical spectroscopy for most of them. SNe Iax are spectroscopically similar to SNe Ia, but have lower maximum-light velocities (2000 {approx}< |v| {approx}< 8000 km s{sup -1}), typically lower peak magnitudes (-14.2 {>=} M{sub V,{sub peak}} {approx}> -18.9 mag), and most have hot photospheres. Relative to SNe Ia, SNe Iax have low luminosities for their light-curve shape. There is a correlation between luminosity and light-curve shape, similar to that of SNe Ia, but offset from that of SNe Ia and with larger scatter. Despite a host-galaxy morphology distribution that is highly skewed to late-type galaxies without any SNe Iax discovered in elliptical galaxies, there are several indications that the progenitor stars are white dwarfs (WDs): evidence of C/O burning in their maximum-light spectra, low (typically {approx}0.5 M{sub Sun }) ejecta masses, strong Fe lines in their late-time spectra, a lack of X-ray detections, and deep limits on massive stars and star formation at the SN sites. However, two SNe Iax show strong He lines in their spectra. The progenitor system and explosion model that best fits all of the data is a binary system of a C/O WD that accretes matter from a He star and has a deflagration. At least some of the time, this explosion will not disrupt the WD. The small number of SNe in this class prohibit a detailed analysis of the homogeneity and heterogeneity of the entire class. We estimate that in a given volume there are 31{sup +17}{sub -13} SNe Iax for every 100 SNe Ia, and for every 1 M{sub Sun} of iron generated by SNe Ia at z = 0, SNe Iax generate {approx}0.036 M{sub Sun }. Being the largest class of peculiar SNe, thousands of SNe Iax will be discovered by LSST. Future detailed observations of SNe Iax should

  11. SN 2012au: A GOLDEN LINK BETWEEN SUPERLUMINOUS SUPERNOVAE AND THEIR LOWER-LUMINOSITY COUNTERPARTS

    Energy Technology Data Exchange (ETDEWEB)

    Milisavljevic, Dan; Soderberg, Alicia M.; Margutti, Raffaella; Drout, Maria R.; Marion, G. Howie; Sanders, Nathan E.; Lunnan, Ragnhild; Chornock, Ryan; Berger, Edo; Foley, Ryan J.; Challis, Pete; Kirshner, Robert P.; Dittmann, Jason; Bieryla, Allyson; Kamble, Atish; Chakraborti, Sayan [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Hsiao, Eric Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Fesen, Robert A.; Parrent, Jerod T. [6127 Wilder Lab, Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States); Levesque, Emily M., E-mail: dmilisav@cfa.harvard.edu [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); and others

    2013-06-20

    We present optical and near-infrared observations of SN 2012au, a slow-evolving supernova (SN) with properties that suggest a link between subsets of energetic and H-poor SNe and superluminous SNe. SN 2012au exhibited conspicuous Type-Ib-like He I lines and other absorption features at velocities reaching Almost-Equal-To 2 Multiplication-Sign 10{sup 4} km s{sup -1} in its early spectra, and a broad light curve that peaked at M{sub B} = -18.1 mag. Models of these data indicate a large explosion kinetic energy of {approx}10{sup 52} erg and {sup 56}Ni mass ejection of M{sub Ni} Almost-Equal-To 0.3 M{sub Sun} on par with SN 1998bw. SN 2012au's spectra almost one year after explosion show a blend of persistent Fe II P-Cyg absorptions and nebular emissions originating from two distinct velocity regions. These late-time emissions include strong [Fe II], [Ca II], [O I], Mg I], and Na I lines at velocities {approx}> 4500 km s{sup -1}, as well as O I and Mg I lines at noticeably smaller velocities {approx}< 2000 km s{sup -1}. Many of the late-time properties of SN 2012au are similar to the slow-evolving hypernovae SN 1997dq and SN 1997ef, and the superluminous SN 2007bi. Our observations suggest that a single explosion mechanism may unify all of these events that span -21 {approx}< M{sub B} {approx}< -17 mag. The aspherical and possibly jetted explosion was most likely initiated by the core collapse of a massive progenitor star and created substantial high-density, low-velocity Ni-rich material.

  12. SN 2009ip and SN 2010mc: Early and late-time behavior consistent with core-collapse Type IIn supernovae

    CERN Document Server

    Smith, Nathan; Prieto, Jose

    2013-01-01

    The recent supernova (SN) 2009ip had pre-SN eruptions followed by a final explosion in 2012. Its pre-SN observations make 2009ip the best observed SN progenitor in history, but the unprecedented data on the pre-SN activity has fueled debate about the nature of the 2012 explosion, whether it was a true SN or some extreme non-terminal event. In principle, both types of events could power shock interaction with circumstellar material (CSM), but here we argue that only a core-collapse SN provides a self-consistent explanation. Previously, we demonstrated that the light curves of SN 2009ip and another Type IIn, SN 2010mc, were nearly identical. Here we expand that comparison to their spectra as well, demonstrating that they are both consistent with known Type IIn events. The late-time spectra of SN 2009ip resemble those of the super-luminous SN 2006tf, and the underlying broad component in SN 2009ip's spectra resembles Type II-P events. The recent claim that the late-time spectrum of SN 2009ip is returning to its ...

  13. The explosion of supernova 2011fe in the frame of the core-degenerate scenario

    CERN Document Server

    Soker, Noam; Althaus, Leandro G

    2013-01-01

    We argue that the properties of the Type Ia supernova (SN Ia) SN 2011fe can be best explained within the frame of the core-degenerate (CD) scenario. In the CD scenario a white dwarf (WD) merges with the core of an asymptotic giant branch (AGB) star and forms a rapidly rotating WD, with a mass close to and above the critical mass for explosion. Rapid rotation prevents immediate collapse and/or explosion. Spinning down over a time of 0-10 Gyr brings the WD to explosion. A very long delayed explosion to post-crystallization phase, which lasts for ~2 Gyr leads to the formation of a highly carbon-enriched outer layer. This can account for the carbon-rich composition of the fastest-moving ejecta of SN 2011fe. In reaching the conclusion that the CD scenario best explains the observed properties of SN 2011fe we consider both its specific properties, like a very compact exploding object and carbon rich composition of the fastest-moving ejecta, and the general properties of SNe Ia.

  14. Scattered-Light Echoes from the Historical Galactic Supernovae Cassiopeia A and Tycho (SN 1572)

    Energy Technology Data Exchange (ETDEWEB)

    Rest, A; Welch, D L; Suntzeff, N B; Oaster, L; Lanning, H; Olsen, K; Smith, R C; Becker, A C; Bergmann, M; Challis, P; Clocchiatti, A; Cook, K H; Damke, G; Garg, A; Huber, M E; Matheson, T; Minniti, D; Prieto, J L; Wood-Vasey, W M

    2008-05-06

    We report the discovery of an extensive system of scattered light echo arclets associated with the recent supernovae in the local neighborhood of the Milky Way: Tycho (SN 1572) and Cassiopeia A. Existing work suggests that the Tycho SN was a thermonuclear explosion while the Cas A supernova was a core collapse explosion. Precise classifications according to modern nomenclature require spectra of the outburst light. In the case of ancient SNe, this can only be done with spectroscopy of their light echo, where the discovery of the light echoes from the outburst light is the first step. Adjacent light echo positions suggest that Cas A and Tycho may share common scattering dust structures. If so, it is possible to measure precise distances between historical Galactic supernovae. On-going surveys that alert on the development of bright scattered-light echo features have the potential to reveal detailed spectroscopic information for many recent Galactic supernovae, both directly visible and obscured by dust in the Galactic plane.

  15. Constraints on explosive silicon burning in core-collapse supernovae from measured Ni/Fe ratios

    CERN Document Server

    Jerkstrand, A; Magkotsios, G; Sim, S A; Fransson, C; Spyromilio, J; Heger, A; Müller, B; Sollerman, J; Smartt, S J

    2015-01-01

    Measurements of explosive nucleosynthesis yields in core-collapse supernovae provide tests for explosion models. We investigate constraints on explosive conditions derivable from measured amounts of nickel and iron after radioactive decays using nucleosynthesis networks with parameterized thermodynamic trajectories. The Ni/Fe ratio is for most regimes dominated by the production ratio of 58Ni/(54Fe + 56Ni), which tends to grow with higher neutron excess and with higher entropy. For SN 2012ec, a supernova that produced a Ni/Fe ratio of $3.4\\pm1.2$ times solar, we find that burning of a fuel with neutron excess $\\eta \\approx 6\\times 10^{-3}$ is required. Unless the progenitor metallicity is over 5 times solar, the only layer in the progenitor with such a neutron excess is the silicon shell. Supernovae producing large amounts of stable nickel thus suggest that this deep-lying layer can be, at least partially, ejected in the explosion. We find that common spherically symmetric models of $M_{\\rm ZAMS} \\lesssim 13$...

  16. SN 2011dh: DISCOVERY OF A TYPE IIb SUPERNOVA FROM A COMPACT PROGENITOR IN THE NEARBY GALAXY M51

    Energy Technology Data Exchange (ETDEWEB)

    Arcavi, Iair; Gal-Yam, Avishay; Yaron, Ofer; Sternberg, Assaf; Rabinak, Itay; Waxman, Eli [Department of Particle Physics and Astrophysics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Kasliwal, Mansi M.; Quimby, Robert M.; Ofek, Eran O.; Horesh, Assaf; Kulkarni, Shrinivas R. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Filippenko, Alexei V.; Silverman, Jeffrey M.; Cenko, S. Bradley; Li, Weidong; Bloom, Joshua S.; Nugent, Peter E.; Poznanski, Dovi [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Sullivan, Mark [Department of Physics (Astrophysics), University of Oxford, Keble Road, Oxford, OX1 3RH (United Kingdom); Gorbikov, Evgeny, E-mail: iair.arcavi@weizmann.ac.il [The Wise Observatory and the Raymond and Beverly Sackler School of Physics and Astronomy, the Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel); and others

    2011-12-15

    On 2011 May 31 UT a supernova (SN) exploded in the nearby galaxy M51 (the Whirlpool Galaxy). We discovered this event using small telescopes equipped with CCD cameras and also detected it with the Palomar Transient Factory survey, rapidly confirming it to be a Type II SN. Here, we present multi-color ultraviolet through infrared photometry which is used to calculate the bolometric luminosity and a series of spectra. Our early-time observations indicate that SN 2011dh resulted from the explosion of a relatively compact progenitor star. Rapid shock-breakout cooling leads to relatively low temperatures in early-time spectra, compared to explosions of red supergiant stars, as well as a rapid early light curve decline. Optical spectra of SN 2011dh are dominated by H lines out to day 10 after explosion, after which He I lines develop. This SN is likely a member of the cIIb (compact IIb) class, with progenitor radius larger than that of SN 2008ax and smaller than the eIIb (extended IIb) SN 1993J progenitor. Our data imply that the object identified in pre-explosion Hubble Space Telescope images at the SN location is possibly a companion to the progenitor or a blended source, and not the progenitor star itself, as its radius ({approx}10{sup 13} cm) would be highly inconsistent with constraints from our post-explosion spectra.

  17. Polarisation Spectral Synthesis For Type Ia Supernova Explosion Models

    Science.gov (United States)

    Bulla, Mattia

    2017-02-01

    Despite their relevance across a broad range of astrophysical research topics, Type Ia supernova explosions are still poorly understood and answers to the questions of when, why and how these events are triggered remain unclear. In this respect, polarisation offers a unique opportunity to discriminate between the variety of possible scenarios. The observational evidence that Type Ia supernovae are associated with rather low polarisation signals (smaller than a few per cent) places strong constraints for models and calls for modest asphericities in the progenitor system and/or explosion mechanism.The goal of this thesis is to assess the validity of contemporary Type Ia supernova explosion models by testing whether their predicted polarisation signatures can account for the small signals usually observed. To this end, we have implemented and tested an innovative Monte Carlo scheme in the radiative transfer code artis. Compared to previous Monte Carlo approaches, this technique produces synthetic observables (light curves, flux and polarisation spectra) with a substantial reduction in the Monte Carlo noise and therefore in the required computing time. This improvement is particularly crucial for our study as we aim to extract very weak polarisation signals, comparable to those detected in Type Ia supernovae. We have also demonstrated the applicability of this method to other classes of supernovae via a preliminary study of the first spectropolarimetry observations of superluminous supernovae.Using this scheme, we have calculated synthetic spectropolarimetry for three multi-dimensional explosion models recently proposed as promising candidates to explain Type Ia supernovae. Our findings highlight the power of spectropolarimetry in testing and discriminating between different scenarios. While all the three models predict light curves and flux spectra that are similar to each others and reproduce those observed in Type Ia supernovae comparably well, polarisation does

  18. A simple approach to the supernova progenitor-explosion connection

    Science.gov (United States)

    Müller, Bernhard; Heger, Alexander; Liptai, David; Cameron, Joshua B.

    2016-07-01

    We present a new approach to understand the landscape of supernova explosion energies, ejected nickel masses, and neutron star birth masses. In contrast to other recent parametric approaches, our model predicts the properties of neutrino-driven explosions based on the pre-collapse stellar structure without the need for hydrodynamic simulations. The model is based on physically motivated scaling laws and simple differential equations describing the shock propagation, the contraction of the neutron star, the neutrino emission, the heating conditions, and the explosion energetics. Using model parameters compatible with multi-D simulations and a fine grid of thousands of supernova progenitors, we obtain a variegated landscape of neutron star and black hole formation similar to other parametrized approaches and find good agreement with semi-empirical measures for the `explodability' of massive stars. Our predicted explosion properties largely conform to observed correlations between the nickel mass and explosion energy. Accounting for the coexistence of outflows and downflows during the explosion phase, we naturally obtain a positive correlation between explosion energy and ejecta mass. These correlations are relatively robust against parameter variations, but our results suggest that there is considerable leeway in parametric models to widen or narrow the mass ranges for black hole and neutron star formation and to scale explosion energies up or down. Our model is currently limited to an all-or-nothing treatment of fallback and there remain some minor discrepancies between model predictions and observational constraints.

  19. SN 2011fu: A type IIb Supernova with a luminous double-peaked light curve

    CERN Document Server

    Morales-Garoffolo, A; Bersten, M; Jerkstrand, A; Taubenberger, S; Benetti, S; Cappellaro, E; Kotak, R; Pastorello, A; Bufano, F; Domínguez, R M; Ergon, M; Fraser, M; Gao, X; García, E; Howell, D A; Isern, J; Smartt, S J; Tomasella, L; Valenti, S

    2015-01-01

    We present optical and near infrared observations of the type IIb supernova (SN) 2011fu from a few days to $\\sim300$ d after explosion. The SN presents a double-peaked light curve (LC) similar to that of SN 1993J, although more luminous and with a longer cooling phase after the primary peak. The spectral evolution is also similar to SN 1993J's, with hydrogen dominating the spectra to $\\sim40$ d, then helium gaining strength, and nebular emission lines appearing from $\\sim60$ d post-explosion. The velocities derived from the P-Cygni absorptions are overall similar to those of other type IIb SNe. We have found a strong similarity between the oxygen and magnesium line profiles at late times, which suggests that these lines are forming at the same location within the ejecta. The hydrodynamical modelling of the pseudo-bolometric LC and the observed photospheric velocities suggest that SN 2011fu was the explosion of an extended star ($\\rm R\\sim450$ R$_\\odot$), in which 1.3 $\\times 10^{51}$ erg of kinetic energy wer...

  20. The Unprecedented Third Outburst of SN 2009ip: A Luminous Blue Variable Becomes a Supernova

    CERN Document Server

    Mauerhan, Jon C; Filippenko, Alexei; Blanchard, Kyle; Blanchard, Peter; Casper, Chadwick F E; Cenko, S Bradley; Clubb, Kelsey I; Cohen, Daniel; Li, Gary; Silverman, Jeffrey M

    2012-01-01

    Some reports of supernova (SN) discoveries turn out not to be true core-collapse explosions. One such case was SN 2009ip, which was recognized to be a luminous blue variable (LBV) eruption. This source had a massive (50-80 Msun) hot progenitor star identified in pre-explosion data, it had documented evidence of pre-outburst variability, and it was subsequently discovered to have a 2nd outburst in 2010. This same source rebrightened again in 2012, and early spectra showed the same narrow-line profiles as before, suggesting another LBV-like eruption. We present new photometry and spectroscopy of SN 2009ip, indicating that its 3rd observed outburst in under 4 years appears to have transitioned into a genuine SN. The most striking discovery in these data is that unlike previous reports, the spectrum exhibited Balmer lines with very broad P-Cygni profiles characteristic of normal Type II supernovae (SNe II), in addition to narrow emission lines seen in SNe IIn and LBVs. Emission components have FWHM 8000 km/s, whi...

  1. The Unusual Super-luminous Supernovae SN 2011kl and ASASSN-15lh

    Science.gov (United States)

    Bersten, Melina C.; Benvenuto, Omar G.; Orellana, Mariana; Nomoto, Ken'ichi

    2016-01-01

    Two recently discovered very luminous supernovae (SNe) present stimulating cases to explore the extents of the available theoretical models. SN 2011kl represents the first detection of a supernova explosion associated with an ultra-long duration gamma-ray burst. ASASSN-15lh was even claimed as the most luminous SN ever discovered, challenging the scenarios so far proposed for stellar explosions. Here we use our radiation hydrodynamics code in order to simulate magnetar-powered SNe. To avoid explicitly assuming neutron star properties, we adopt the magnetar luminosity and spin-down timescale as free parameters of the model. We find that the light curve (LC) of SN 2011kl is consistent with a magnetar power source, as previously proposed, but we note that some amount of 56Ni (≳ 0.08{M}⊙ ) is necessary to explain the low contrast between the LC peak and tail. For the case of ASASSN-15lh, we find physically plausible magnetar parameters that reproduce the overall shape of the LC provided the progenitor mass is relatively large (an ejecta mass of ≈ 6{M}⊙ ). The ejecta hydrodynamics of this event is dominated by the magnetar input, while the effect is more moderate for SN 2011kl. We conclude that a magnetar model may be used for the interpretation of these events and that the hydrodynamical modeling is necessary to derive the properties of powerful magnetars and their progenitors.

  2. Nonspherical supernova remnants. IV - Sequential explosions in OB associations

    Science.gov (United States)

    Tenorio-Tagle, G.; Bodenheimer, P.; Rozyczka, M.

    1987-01-01

    Multisupernova remnants, driven by sequential supernova explosions in OB associations, are modelled by means of two-dimensional hydrodynamical calculations. It is shown that due to the Rayleigh-Taylor instability the remnants quickly evolve into highly irregular structures. A critical evaluation of the multisupernova model as an explanation for supershells is given.

  3. Finding the First Cosmic Explosions. III. Pair-Pulsational Supernovae

    CERN Document Server

    Whalen, Daniel J; Even, Wesley; Woosley, S E; Heger, Alexander; Stiavelli, Massimo; Fryer, Chris L

    2013-01-01

    Population III supernovae have been the focus of growing attention because of their potential to directly probe the properties of the first stars, particularly the most energetic events that can be seen at the edge of the observable universe. But until now pair-pulsation supernovae, in which explosive thermonuclear burning in massive stars fails to unbind them but can eject their outer layers into space, have been overlooked as cosmic beacons at the earliest redshifts. These shells can later collide and, like Type IIn supernovae, produce superluminous events in the UV at high redshifts that could be detected in the near infrared today. We present numerical simulations of a 110 M$_{\\odot}$ pair-pulsation explosion done with the Los Alamos radiation hydrodynamics code RAGE. We find that collisions between consecutive pair pulsations are visible in the near infrared out to z $\\sim$ 15 - 20 and can probe the earliest stellar populations at cosmic dawn.

  4. Endurance of SN 2005ip after a decade: X-rays, radio and Hα like SN 1988Z require long-lived pre-supernova mass-loss

    Science.gov (United States)

    Smith, Nathan; Kilpatrick, Charles D.; Mauerhan, Jon C.; Andrews, Jennifer E.; Margutti, Raffaella; Fong, Wen-Fai; Graham, Melissa L.; Zheng, WeiKang; Kelly, Patrick L.; Filippenko, Alexei V.; Fox, Ori D.

    2017-04-01

    Supernova (SN) 2005ip was a Type IIn event notable for its sustained strong interaction with circumstellar material (CSM), coronal emission lines and infrared (IR) excess, interpreted as shock interaction with the very dense and clumpy wind of an extreme red supergiant. We present a series of late-time spectra of SN 2005ip and a first radio detection of this SN, plus late-time X-rays, all of which indicate that its CSM interaction is still strong a decade post-explosion. We also present and discuss new spectra of geriatric SNe with continued CSM interaction: SN 1988Z, SN 1993J and SN 1998S. From 3 to 10 yr post-explosion, SN 2005ip's Hα luminosity and other observed characteristics were nearly identical to those of the radio-luminous SN 1988Z, and much more luminous than SNe 1993J and 1998S. At 10 yr after explosion, SN 2005ip showed a drop in Hα luminosity, followed by a quick resurgence over several months. We interpret this Hα variability as ejecta crashing into a dense shell located ≲ 0.05 pc from the star, which may be the same shell that caused the IR echo at earlier epochs. The extreme Hα luminosities in SN 2005ip and SN 1988Z are still dominated by the forward shock at 10 yr post-explosion, whereas SN 1993J and SN 1998S are dominated by the reverse shock at a similar age. Continuous strong CSM interaction in SNe 2005ip and 1988Z is indicative of enhanced mass-loss for ∼103 yr before core collapse, longer than Ne, O or Si burning phases. Instead, the episodic mass-loss must extend back through C burning and perhaps even part of He burning.

  5. Nearby Supernova Factory Observations of SN 2006D: On SporadicCarbon Signatures in Early Type Ia Supernova Spectra

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, R.C.; Aldering, G.; Antilogus, P.; Aragon, C.; Bailey,S.; Baltay, C.; Baron, E.; Bauer, A.; Buton, C.; Bongard, S.; Copin, Y.; Gangler, E.; Gilles, S.; Kessler, R.; Loken, S.; Nugent, P.; Pain, R.; Parrent, J.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigaudier, G.; Runge, K.; Scalzo, R.; Smadja, G.; Wang, L.; Weaver, B.A.

    2006-10-12

    We present four spectra of the Type Ia supernova SN Ia 2006Dextending from -7 to +13 days with respect to B-band maximum. The spectrainclude the strongest signature of unburned material at photosphericvelocities observed in a SN Ia to date. The earliest spectrum exhibits CII absorption features below 14,000 km/s, including a distinctive C IIlambda 6580 absorption feature. The carbon signatures dissipate as the SNapproaches peak brightness. In addition to discussing implications ofphotospheric-velocity carbon for white dwarf explosion models, we outlinesome factors that may influence the frequency of its detection before andaround peak brightness. Two effects are explored in this regard,including depopulation of the C II optical levels by non-LTE effects, andline-of-sight effects resulting from a clumpy distribution of unburnedmaterial with low volume-filling factor.

  6. Nearby Supernova Factory Observations of SN 2005gj: Another TypeIa Supernova in a Massive Circumstellar Envelope

    Energy Technology Data Exchange (ETDEWEB)

    Aldering, G.; Antilogus, P.; Bailey, S.; Baltay, C.; Bauer, A.; Blanc, N.; Bongard, S.; Copin, Y.; Gangler, E.; Gilles, S.; Kessler, R.; Kocevski, D.; Lee, B.C.; Loken, S.; Nugent, P.; Pain, R.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigaudier, G.; Scalzo, R.; Smadja, G.; Thomas, R.C.; Wang, L.; Weaver, B.A.; Rabinowitz, D.; Bauer, A.

    2006-06-01

    We report the independent discovery and follow-up observations of supernova 2005gj by the Nearby Supernova Factory. This is the second confirmed case of a ''hybrid'' Type Ia/IIn supernova, which like the prototype SN 2002ic, we interpret as the explosion of a white dwarf interacting with a circumstellar medium. Our early-phase photometry of SN 2005gj shows that the strength of the interaction between the supernova ejecta and circumstellar material is much stronger than for SN 2002ic. Our .rst spectrum shows a hot continuum with broad and narrow H{alpha} emission. Later spectra, spanning over 4 months from outburst, show clear Type Ia features combined with broad and narrow H{gamma}, H{beta},H{alpha} and He I {lambda}{lambda}5876,7065 in emission. At higher resolution, P Cygni profiles are apparent. Surprisingly, we also observe an inverted P Cygni profile for [O III] {lambda}5007. We find that the lightcurve and measured velocity of the unshocked circumstellar material imply mass loss as recently as 8 years ago. This is in contrast to SN 2002ic, for which an inner cavity in the circumstellar material was inferred. Within the context of the thin-shell approximation, the early lightcurve is well-described by a flat radial density profile for the circumstellar material. However, our decomposition of the spectra into Type Ia and shock emission components allows for little obscuration of the supernova, suggesting an aspherical or clumpy distribution for the circumstellar material. We suggest that the emission line velocity profiles arise from electron scattering rather than the kinematics of the shock. This is supported by the inferred high densities, and the lack of evidence for evolution in the line widths. Ground- and space-based photometry, and Keck spectroscopy, of the host galaxy are used to ascertain that the host galaxy has low metallicity (Z/Z{sub {circle_dot}} < 0.3; 95% confidence) and that this galaxy is undergoing a significant star

  7. Very-high-energy gamma-ray observations of the Type Ia Supernova SN 2014J with the MAGIC telescopes

    Science.gov (United States)

    Ahnen, M. L.; Ansoldi, S.; Antonelli, L. A.; Antoranz, P.; Arcaro, C.; Babic, A.; Banerjee, B.; Bangale, P.; Barres de Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Berti, A.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Borracci, F.; Bretz, T.; Carosi, R.; Carosi, A.; Chatterjee, A.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Cumani, P.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Lotto, B.; de Oña Wilhelmi, E.; Di Pierro, F.; Doert, M.; Domínguez, A.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Eisenacher Glawion, D.; Elsaesser, D.; Engelkemeier, M.; Fallah Ramazani, V.; Fernández-Barral, A.; Fidalgo, D.; Fonseca, M. V.; Font, L.; Frantzen, K.; Fruck, C.; Galindo, D.; García López, R. J.; Garczarczyk, M.; Garrido Terrats, D.; Gaug, M.; Giammaria, P.; Godinović, N.; Gora, D.; Guberman, D.; Hadasch, D.; Hahn, A.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Hughes, G.; Idec, W.; Kodani, K.; Konno, Y.; Kubo, H.; Kushida, J.; La Barbera, A.; Lelas, D.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; López-Coto, R.; Majumdar, P.; Makariev, M.; Mallot, K.; Maneva, G.; Manganaro, M.; Mannheim, K.; Maraschi, L.; Marcote, B.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Miranda, J. M.; Mirzoyan, R.; Moralejo, A.; Moretti, E.; Nakajima, D.; Neustroev, V.; Niedzwiecki, A.; Nievas Rosillo, M.; Nilsson, K.; Nishijima, K.; Noda, K.; Nogués, L.; Paiano, S.; Palacio, J.; Palatiello, M.; Paneque, D.; Paoletti, R.; Paredes, J. M.; Paredes-Fortuny, X.; Pedaletti, G.; Peresano, M.; Perri, L.; Persic, M.; Poutanen, J.; Prada Moroni, P. G.; Prandini, E.; Puljak, I.; Garcia, J. R.; Reichardt, I.; Rhode, W.; Ribó, M.; Rico, J.; Saito, T.; Satalecka, K.; Schroeder, S.; Schweizer, T.; Sillanpää, A.; Sitarek, J.; Snidaric, I.; Sobczynska, D.; Stamerra, A.; Strzys, M.; Surić, T.; Takalo, L.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Tescaro, D.; Teshima, M.; Torres, D. F.; Toyama, T.; Treves, A.; Vanzo, G.; Vazquez Acosta, M.; Vovk, I.; Ward, J. E.; Will, M.; Wu, M. H.; Zanin, R.

    2017-06-01

    Context. In this work we present data from observations with the MAGIC telescopes of SN 2014J detected on January 21 2014, the closest Type Ia supernova since Imaging Air Cherenkov Telescopes started to operate. Aims: We aim to probe the possibility of very-high-energy (VHE; E ≥ 100 GeV) gamma rays produced in the early stages of Type Ia supernova explosions. Methods: We performed follow-up observations after this supernova (SN) explosion for five days, between January 27 and February 2 2014. We searched for gamma-ray signals in the energy range between 100 GeV and several TeV from the location of SN 2014J using data from a total of 5.5 h of observations. Prospects for observing gamma rays of hadronic origin from SN 2014J in the near future are also being addressed. Results: No significant excess was detected from the direction of SN 2014J. Upper limits at 95% confidence level on the integral flux, assuming a power-law spectrum, dF/dE ∝ E- Γ, with a spectral index of Γ = 2.6, for energies higher than 300 GeV and 700 GeV, are established at 1.3 × 10-12 and 4.1 × 10-13 photons cm-2 s-1, respectively. Conclusions: For the first time, upper limits on the VHE emission of a Type Ia supernova are established. The energy fraction isotropically emitted into TeV gamma rays during the first 10 days after the supernova explosion for energies greater than 300 GeV is limited to 10-6 of the total available energy budget ( 1051 erg). Within the assumed theoretical scenario, the MAGIC upper limits on the VHE emission suggest that SN 2014J will not be detectable in the future by any current or planned generation of Imaging Atmospheric Cherenkov Telescopes.

  8. SN 2009ib: A Type II-P Supernova with an Unusually Long Plateau

    CERN Document Server

    Takats, K; Pumo, M L; Paillas, E; Zampieri, L; Elias-Rosa, N; Benetti, S; Bufano, F; Cappellaro, E; Ergon, M; Fraser, M; Hamuy, M; Inserra, C; Kankare, E; Smartt, S J; Stritzinger, M D; Van Dyk, S D; Haislip, J B; LaCluyze, A P; Moore, J P; Reichart, D

    2015-01-01

    We present optical and near-infrared photometry and spectroscopy of SN 2009ib, a Type II-P supernova in NGC 1559. This object has moderate brightness, similar to those of the intermediate-luminosity SNe 2008in and 2009N. Its plateau phase is unusually long, lasting for about 130 days after explosion. The spectra are similar to those of the subluminous SN 2002gd, with moderate expansion velocities. We estimate the $^{56}$Ni mass produced as $0.046 \\pm 0.015\\,{\\rm M}_{\\sun}$. We determine the distance to SN 2009ib using both the expanding photosphere method (EPM) and the standard candle method. We also apply EPM to SN 1986L, a type II-P SN that exploded in the same galaxy. Combining the results of different methods, we conclude the distance to NGC 1559 as $D=19.8 \\pm 2.8$ Mpc. We examine archival, pre-explosion images of the field taken with the Hubble Space Telescope, and find a faint source at the position of the SN, which has a yellow colour ($(V-I)_0 = 0.85$ mag). Assuming it is a single star, we estimate i...

  9. The Peculiar Type Ib Supernova 2006jc: A WC Star Explosion

    CERN Document Server

    Tominaga, N; Suzuki, T; Tanaka, M; Nomoto, K; Maeda, K; Chieffi, A; Tornambé, A; Minezaki, T; Yoshii, Y; Sakon, I; Wada, T; Ohyama, Y; Tanabé, T; Kaneda, H; Onaka, T; Nozawa, T; Kozasa, T; Kawabata, K S; Anupama, G C; Sahu, D K; Gurugubelli, U K; Prabhu, T P; Deng, J

    2007-01-01

    We present a theoretical model for Type Ib supernova (SN) 2006jc associated with a luminous blue variable (LBV)-like event. We calculate the presupernova evolution of the progenitor star, hydrodynamics and nucleosynthesis of the SN explosion, and the SN bolometric light curve (LC). The observed bolometic LC is constructed by integrating the UV, optical, near-infrared (NIR), and mid-infrared (MIR) fluxes. The progenitor is assumed to be as massive as $40\\Msun$ on the zero-age. The star undergoes extensive mass loss to reduce its mass down to as small as $6.9\\Msun$, thus becoming a WC Wolf-Rayet star at the presupernova stage. The WC star model has a thick carbon-rich layer, in which amorphous carbon grains can be formed during the explosion. This could explain the brightening in the NIR flux and the observed dust feature in MIR. The typical main-sequence mass of a WC Wolf-Rayet star and thus the progenitor of SN 2006jc is more massive than $40\\Msun$. We suggest that the explosions of stars more massive than $4...

  10. SN 2002cx The Most Peculiar Known Type Ia Supernova

    CERN Document Server

    Li, W; Chornock, R; Berger, E; Berlind, P; Calkins, M L; Challis, P M; Fassnacht, C D; Jha, S; Kirshner, R P; Matheson, T; Sargent, W L W; Simcoe, R A; Smith, G H; Squires, G; Li, Weidong; Filippenko, Alexei V.; Chornock, Ryan; Berger, Edo; Berlind, Perry; Calkins, Michael L.; Challis, Peter; Fassnacht, Chris; Jha, Saurabh; Kirshner, Robert P.; Matheson, Thomas; Sargent, Wallace L. W.; Simcoe, Robert A.; Smith, Graeme H.; Squires, Gordon

    2003-01-01

    We present photometric and spectroscopic observations of supernova (SN) 2002cx, which reveal it to be unique among all observed type Ia supernovae (SNe Ia). SN 2002cx exhibits a SN 1991T-like premaximum spectrum, a SN 1991bg-like luminosity, and expansion velocities roughly half those of normal SNe Ia. Photometrically, SN 2002cx has a broad peak in the $R$ band and a plateau phase in the $I$ band, and slow late-time decline. The $(B - V)$ color evolution is nearly normal, but the $(V - R)$ and $(V - I)$ colors are very red. Early-time spectra of SN 2002cx evolve very quickly and are dominated by lines from Fe-group elements; features from intermediate-mass elements (Ca, S, Si) are weak or absent. Mysterious emission lines are observed around 7000 \\AA\\ at about 3 weeks after maximum brightness. The nebular spectrum of SN 2002cx is also unique, consisting of narrow iron and cobalt lines. The observations of SN 2002cx are inconsistent with the observed spectral/photometric sequence, and provide a major challenge...

  11. The energy and momentum input of supernova explosions in structured and ionised molecular clouds

    CERN Document Server

    Walch, S K

    2014-01-01

    We investigate the early impact of single and binary supernova (SN) explosions on dense gas clouds with three-dimensional, high-resolution, hydrodynamic simulations. The effect of cloud structure, radiative cooling, and ionising radiation from the progenitor stars on the net input of kinetic energy, f_kin=E_kin/E_SN, thermal energy, f_therm=E_therm/E_SN, and gas momentum f_P=P/P_SN to the interstellar medium (ISM) is tested. For clouds with n=100 cm^{-3}, the momentum generating Sedov and pressure-driven snowplough phases are terminated early (~ 0.01 Myr) and radiative cooling limits the coupling to f_therm ~ 0.01, f_kin ~ 0.05, and f_P ~ 9, significantly lower than for the case without cooling. For pre-ionised clouds these numbers are only increased by ~ 50%, independent of the cloud structure. This only suffices to accelerate ~ 5% of the cloud to radial velocities >30km/s. A second SN might further enhance the coupling efficiencies if delayed past the Sedov phase of the first explosion. Such very low coupli...

  12. Supernova Remnant Evolution: from explosion to dissipation

    CERN Document Server

    Leahy, Denis

    2016-01-01

    Here is considered the full evolution of a spherical supernova remnant. We start by calculating the early time ejecta dominated stage and continue through the different phases of interaction with the circumstellar medium, and end with the dissipation and merger phase. The physical connection between the phases reveals new results. One is that the blast wave radius during the adiabatic phase is significantly smaller than it would be, if one does notaccount for the blast wave interaction with the ejecta.

  13. Supernova SN 2011fe from an exploding carbon-oxygen white dwarf star.

    Science.gov (United States)

    Nugent, Peter E; Sullivan, Mark; Cenko, S Bradley; Thomas, Rollin C; Kasen, Daniel; Howell, D Andrew; Bersier, David; Bloom, Joshua S; Kulkarni, S R; Kandrashoff, Michael T; Filippenko, Alexei V; Silverman, Jeffrey M; Marcy, Geoffrey W; Howard, Andrew W; Isaacson, Howard T; Maguire, Kate; Suzuki, Nao; Tarlton, James E; Pan, Yen-Chen; Bildsten, Lars; Fulton, Benjamin J; Parrent, Jerod T; Sand, David; Podsiadlowski, Philipp; Bianco, Federica B; Dilday, Benjamin; Graham, Melissa L; Lyman, Joe; James, Phil; Kasliwal, Mansi M; Law, Nicholas M; Quimby, Robert M; Hook, Isobel M; Walker, Emma S; Mazzali, Paolo; Pian, Elena; Ofek, Eran O; Gal-Yam, Avishay; Poznanski, Dovi

    2011-12-14

    Type Ia supernovae have been used empirically as 'standard candles' to demonstrate the acceleration of the expansion of the Universe even though fundamental details, such as the nature of their progenitor systems and how the stars explode, remain a mystery. There is consensus that a white dwarf star explodes after accreting matter in a binary system, but the secondary body could be anything from a main-sequence star to a red giant, or even another white dwarf. This uncertainty stems from the fact that no recent type Ia supernova has been discovered close enough to Earth to detect the stars before explosion. Here we report early observations of supernova SN 2011fe in the galaxy M101 at a distance from Earth of 6.4 megaparsecs. We find that the exploding star was probably a carbon-oxygen white dwarf, and from the lack of an early shock we conclude that the companion was probably a main-sequence star. Early spectroscopy shows high-velocity oxygen that slows rapidly, on a timescale of hours, and extensive mixing of newly synthesized intermediate-mass elements in the outermost layers of the supernova. A companion paper uses pre-explosion images to rule out luminous red giants and most helium stars as companions to the progenitor.

  14. The Unusual Super-Luminous Supernovae SN 2011kl and ASASSN-15lh

    CERN Document Server

    Bersten, Melina C; Orellana, Mariana; Nomoto, Ken'ichi

    2016-01-01

    Two recently discovered very luminous supernovae (SNe) present stimulating cases to explore the extents of the available theoretical models. SN 2011kl represents the first detection of a supernova explosion associated with an ultra-long duration gamma ray burst. ASASSN-15lh was even claimed as the most luminous SN ever discovered, challenging the scenarios so far proposed for stellar explosions. Here we use our radiation hydrodynamics code in order to simulate magnetar powered SNe. To avoid explicitly assuming neutron star properties we adopt the magnetar luminosity and spin-down timescale as free parameters of the model. We find that the light curve (LC) of SN 2011kl is consistent with a magnetar power source, as previously proposed, but we note that some amount of 56^Ni (> 0.08 M_sun) is necessary to explain the low contrast between the LC peak and tail. For the case of ASASSN-15lh we find physically plausible magnetar parameters that reproduce the overall shape of the LC provided the progenitor mass is rel...

  15. Neutron star kicks by the gravitational tug-boat mechanism in asymmetric supernova explosions: progenitor and explosion dependence

    CERN Document Server

    Janka, H -Th

    2016-01-01

    Asymmetric mass ejection in the early phase of supernova (SN) explosions can impart a kick velocity to the new-born neutron star (NS). For neutrino-driven explosions the NS acceleration was shown to be mainly caused by the gravitational attraction of the anisotropically expelled inner ejecta, while hydrodynamic forces contribute on a subdominant level, and asymmetric neutrino emission plays only a secondary role. Two- and three-dimensional hydrodynamic simulations demonstrated that this gravitational tug-boat mechanism can explain the observed space velocities of young NSs up to more than 1000 km/s. Here, we discuss how the NS kick depends on the energy, ejecta mass, and asymmetry of the SN explosion, and which role the compactness of the pre-collapse stellar core plays for the momentum transfer to the NS. We also provide simple analytic expressions for the NS velocity in terms of these quantities. Referring to results of hydrodynamic simulations in the literature, we argue why within the discussed scenario o...

  16. Type Ia supernova explosion mechanism and implications for cosmology

    Science.gov (United States)

    Maeda, K.

    Type Ia Supernovae (SNe Ia) are believed to be thermonuclear explosions of a white dwarf, and are one of the most mature cosmological standardized candles. However, the explosion mechanism has not yet been fully clarified. Furthermore, they show observational diversities which may be a consequence of either the diversity in the explosion physics and/or surrounding environments, an issue yet to be clarified. In this paper, it is argued that an asymmetry in the explosion is likely a generic feature, and that the diversity arising from various viewing angles can be an origin of observational diversities of SNe Ia seen in their spectral features (suspected possible biases in cosmology) and colors (related to the extinction estimate in cosmology). These findings indicate that at least a part of observational diversities are intrinsic, rather than caused by environment effects, and open up a possibility of using SNe Ia as more precise distance indicators than currently employed.

  17. Hubble space telescope and ground-based observations of the type Iax supernovae SN 2005hk and SN 2008A

    Energy Technology Data Exchange (ETDEWEB)

    McCully, Curtis; Jha, Saurabh W. [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Foley, Ryan J. [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Chornock, Ryan [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Holtzman, Jon A. [Department of Astronomy, MSC 4500, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003 (United States); Balam, David D. [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Branch, David [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States); Filippenko, Alexei V.; Ganeshalingam, Mohan; Li, Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Frieman, Joshua [Kavli Institute for Cosmological Physics and Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Fynbo, Johan; Leloudas, Giorgos [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen Ø (Denmark); Galbany, Lluis [Institut de Física d' Altes Energies, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona) (Spain); Garnavich, Peter M. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Graham, Melissa L. [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Hsiao, Eric Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Leonard, Douglas C., E-mail: cmccully@physics.rutgers.edu [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); and others

    2014-05-10

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). Here we focus on late-time observations, where these objects deviate most dramatically from all other SN types. Instead of the dominant nebular emission lines that are observed in other SNe at late phases, spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with n{sub e} ≳ 10{sup 9} cm{sup –3}. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected 'infrared catastrophe', a generic feature of SN Ia models. However, our HST photometry of SN 2008A does not match the predictions of an infrared catastrophe. Moreover, our HST observations rule out a 'complete deflagration' that fully disrupts the white dwarf for these peculiar SNe, showing no evidence for unburned material at late times. Deflagration explosion models that leave behind a bound remnant can match some of the observed properties of SNe Iax, but no published model is consistent with all of our observations of SNe 2005hk and 2008A.

  18. An Integral Condition for Core-Collapse Supernova Explosions

    CERN Document Server

    Murphy, Jeremiah W

    2015-01-01

    We derive an integral condition for core-collapse supernova explosions and use it to construct a new diagnostic of explodability. The fundamental challenge in core-collapse supernova theory is to explain how a stalled accretion shock revives to explode a star. In this manuscript, we assume that shock revival is initiated by the delayed-neutrino mechanism and derive an integral condition for shock expansion, $v_s > 0$. Assuming that $v_s > 0$ corresponds to explosion, we recast this integral condition as a dimensionless condition for explosion, $\\Psi > 0$. Using 1D simulations, we confirm that $\\Psi = 0$ during the stalled phase and $\\Psi > 0$ during explosion. Having validated the integral condition, we use it to derive a useful explosion diagnostic. First, for a given set of parameters, we find the family of solutions to the steady-state equations, parameterized by shock radius $R_s$, yielding $\\Psi(R_s)$. For any particular solution, $\\Psi(R_s)$ may be negative, zero, or positive, and, since $\\Psi \\propto v...

  19. Radio and X-rays From SN 2013df Enlighten Progenitors of Type IIb Supernovae

    CERN Document Server

    Kamble, Atish; Soderberg, Alicia M; Chakraborti, Sayan; Fransson, Claes; Chevalier, Roger; Powell, Diana; Milisavljevic, Dan; Parrent, Jerod; Bietenholz, Michael

    2015-01-01

    We present radio and X-ray observations of the nearby Type IIb Supernova 2013df in NGC4414 from 10 to 250 days after the explosion. The radio emission showed a peculiar soft-to-hard spectral evolution. We present a model in which inverse Compton cooling of synchrotron emitting electrons can account for the observed spectral and light curve evolution. A significant mass loss rate, $\\dot{M} \\approx 8 \\times 10^{-5}\\,\\rm M_{\\odot}/yr$ for a wind velocity of 10 km/s, is estimated from the detailed modeling of radio and X-ray emission, which are primarily due to synchrotron and bremsstrahlung, respectively. We show that SN 2013df is similar to SN 1993J in various ways. The shock wave speed of SN 2013df was found to be average among the radio supernovae; $v_{sh}/c \\sim 0.07$. We did not find any significant deviation from smooth decline in the light curve of SN 2013df. One of the main results of our self-consistent multiband modeling is the significant deviation from energy equipartition between magnetic fields and...

  20. A binary scenario for the pre-explosion outburst of the supernova 2010mc

    CERN Document Server

    Soker, Noam

    2013-01-01

    I raise the possibility that the pre-explosion outburst (PEO) of the type IIn supernova 2010mc (PTF 10tel) was energized by mass accretion onto an O main-sequence stellar companion. According to this suggestion the SN progenitor suffered a rapid expansion within months before explosion. The expansion was driven by leakage of energy from the core where vigorous oxygen nuclear burning takes place within a year prior to explosion. This expansion triggered mass transfer onto the secondary star. Most of the extra energy of the outburst comes from the accretion of ~0.1Mo onto the secondary star. As well, the gas outflowing at v~2000 km/s was launched from the accreting secondary star, most likely in a bipolar outflow. The binary model can account for the slower circumstellar medium that was ejected at earlier times, and explain the red-shifted peak of the Halpha emission at 5.8 days past explosion. I compare some properties of the PEO of SN 2010mc to those of other stellar eruptions, such as the stellar merger even...

  1. Supernova explosions in magnetized, primordial dark matter halos

    CERN Document Server

    Seifried, D; Schleicher, D

    2013-01-01

    We present a set of high resolution simulations studying the effect of supernova explosions on magnetized, primordial halos. We focus on the evolution of an initially small-scale magnetic field formed during the collapse of the halo. We vary the degree of magnetization, the halo mass, and the amount of explosion energy in order to account for expected variations as well as to infer systematical dependencies of the results on initial conditions. Our simulations suggest that core collapse supernovae with an explosion energy of 10^51 erg and more violent pair instability supernovae with 10^53 erg are able to disrupt halos with masses up to a few 10^6 and 10^7 M_sun, respectively. The peak of the magnetic field spectra shows a continuous shift towards smaller k-values, i.e. larger length scales, over time reaching values as low as k = 4. On small scales the magnetic energy decreases at the cost of the energy on large scales resulting in well-ordered magnetic field with strengths up to about 10^-8 G depending on t...

  2. 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.

  3. Modeling SNR Cassiopeia A from the Supernova Explosion to its Current Age: The role of post-explosion anisotropies of ejecta

    CERN Document Server

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

    2016-01-01

    The remnants of core-collapse supernovae (SNe) have complex morphologies that may reflect asymmetries and structures developed during the progenitor SN explosion. Here we investigate how the morphology of the SNR Cassiopeia A (Cas A) reflects the characteristics of the progenitor SN with the aim to derive the energies and masses of the post-explosion anisotropies responsible for the observed spatial distribution of Fe and Si/S. We model the evolution of Cas A from the immediate aftermath of the progenitor SN to the three-dimensional interaction of the remnant with the surrounding medium. The post-explosion structure of the ejecta is described by small-scale clumping of material and larger-scale anisotropies. The hydrodynamic multi-species simulations consider an appropriate post-explosion isotopic composition of the ejecta. The observed average expansion rate and shock velocities can be well reproduced by models with ejecta mass $M_{\\rm ej}\\approx 4M_{\\odot}$ and explosion energy $E_{\\rm SN}\\approx 2.3\\times ...

  4. A Subgrid-scale Model for Deflagration-to-Detonation Transitions in Type Ia Supernova Explosion Simulations - Numerical implementation

    CERN Document Server

    Ciaraldi-Schoolmann, F; Roepke, F K

    2013-01-01

    A promising model for normal Type Ia supernova (SN Ia) explosions are delayed detonations of Chandrasekhar-mass white dwarfs, in which the burning starts out as a subsonic deflagration and turns at a later phase of the explosion into a supersonic detonation. The mechanism of the underlying deflagration-to-detonation transition (DDT) is unknown in detail, but necessary conditions have been determined recently. The region of detonation initiation cannot be spatially resolved in multi-dimensional full-star simulations of the explosion. We develop a subgrid-scale (SGS) model for DDTs in thermonuclear supernova simulations that is consistent with the currently known constraints. The probability for a DDT to occur is calculated from the distribution of turbulent velocities measured on the grid scale in the vicinity of the flame and the fractal flame surface area that satisfies further physical constraints, such as fuel fraction and fuel density. The implementation of our DDT criterion provides a solid basis for sim...

  5. SN 2009bb: a Peculiar Broad-Lined Type Ic Supernova

    CERN Document Server

    Pignata, Giuliano; Soderberg, Alicia; Mazzali, Paolo; Phillips, M M; Morrell, Nidia; Anderson, J P; Boldt, Luis; Campillay, Abdo; Contreras, Carlos; Folatelli, Gastón; Förster, Francisco; González, Sergio; Hamuy, Mario; Krzeminski, Wojtek; Maza, José; Roth, Miguel; Levesque, Francisco Salgado Emily M; Rest, Armin; Crain, J Adam; Foster, Andrew C; Haislip, Joshua B; Ivarsen, Kevin M; LaCluyze, Aaron P; Nysewander, Melissa C; Reichart, Daniel E

    2010-01-01

    Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudo-bolometric light curve of SN 2009bb suggests that 4.1+-1.9 Msun of material was ejected with 0.22 +-0.06 Msun of it being 56Ni. The resulting kinetic energy is 1.8+-0.7x10^52 erg. This, together with an absolute peak magnitude of MB=-18.36+-0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission, and high metallicity of its en...

  6. INTEGRAL FIELD SPECTROSCOPY OF SUPERNOVA EXPLOSION SITES: CONSTRAINING THE MASS AND METALLICITY OF THE PROGENITORS. I. TYPE Ib AND Ic SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Kuncarayakti, Hanindyo; Maeda, Keiichi [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Doi, Mamoru; Morokuma, Tomoki; Hashiba, Yasuhito [Institute of Astronomy, Graduate School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Aldering, Greg [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Arimoto, Nobuo [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Pereira, Rui [CNRS/IN2P3, Institut de Physique Nucleaire de Lyon, 4 Rue Enrico Fermi, F-69622 Villeurbanne Cedex (France); Usuda, Tomonori, E-mail: hanindyo.kuncarayakti@ipmu.jp [Subaru Telescope, National Astronomical Observatory of Japan, 650 North A' ohoku Place, Hilo, HI 96720 (United States)

    2013-08-01

    Integral field spectroscopy of 11 Type Ib/Ic supernova (SN Ib/Ic) explosion sites in nearby galaxies has been obtained using UH88/SNIFS and Gemini-N/GMOS. The use of integral field spectroscopy enables us to obtain both spatial and spectral information about the explosion site, enabling the identification of the parent stellar population of the SN progenitor star. The spectrum of the parent population provides metallicity determination via strong-line method and age estimation obtained via comparison with simple stellar population models. We adopt this information as the metallicity and age of the SN progenitor, under the assumption that it was coeval with the parent stellar population. The age of the star corresponds to its lifetime, which in turn gives the estimate of its initial mass. With this method we were able to determine both the metallicity and initial (zero-age main sequence) mass of the progenitor stars of SNe Ib and Ic. We found that on average SN Ic explosion sites are more metal-rich and younger than SN Ib sites. The initial mass of the progenitors derived from parent stellar population age suggests that SN Ic has more massive progenitors than SN Ib. In addition, we also found indication that some of our SN progenitors are less massive than {approx}25 M{sub Sun }, indicating that they may have been stars in a close binary system that have lost their outer envelope via binary interactions to produce SNe Ib/Ic, instead of single Wolf-Rayet stars. These findings support the current suggestions that both binary and single progenitor channels are in effect in producing SNe Ib/Ic. This work also demonstrates the power of integral field spectroscopy in investigating SN environments and active star-forming regions.

  7. Ionized gas velocity dispersion and multiple supernova explosions

    CERN Document Server

    Vasiliev, Evgenii O; Shchekinov, Yuri A

    2014-01-01

    Using 3D numerical simulations we study the evolution of the H$\\alpha$ intensity and velocity dispersion for single and multiple supenova (SN) explosions. We find that the $I_{\\rm H\\alpha}-\\sigma$ diagram obtained for simulated gas flows is similar in shape to that observed in dwarf galaxies. We conclude that colliding SN shells with significant difference in age are resposible for high velocity dispersion that reaches values high as $\\simgt 100$kms$^{-1}$. Such a high velocity dispersion could be hardly got for a single SN remnant. Peaks of velocity dispersion on the $I_{\\rm H\\alpha}-\\sigma$ diagram may correspond to several stand-alone or merged SN remnants with moderately different ages. The procedure of the spatial resolution degrading in the H$\\alpha$ intensity and velocity dispersion maps makes the simulated $I_{\\rm H\\alpha}-\\sigma$ diagrams close to those observed in dwarf galaxies not only in shape, but also quantitatively.

  8. SN 1999ga: a low-luminosity linear type II supernova?

    CERN Document Server

    Pastorello, A; Martin, R; Smartt, S J; Altavilla, G; Benetti, S; Botticella, M T; Cappellaro, E; Mattila, S; Maund, J R; Ryder, S D; Salvo, M; Taubenberger, S; Turatto, M

    2009-01-01

    Type II-linear supernovae are thought to arise from progenitors that have lost most of their H envelope by the time of the explosion, and they are poorly understood because they are only occasionally discovered. It is possible that they are intrinsically rare, but selection effects due to their rapid luminosity evolution may also play an important role in limiting the number of detections. In this context, the discovery of a subluminous type II-linear event is even more interesting. We investigate the physical properties and characterise the explosion site of the type II SN 1999ga, which exploded in the nearby spiral galaxy NGC 2442. Spectroscopic and photometric observations of SN 1999ga allow us to constrain the energetics of the explosion and to estimate the mass of the ejected material, shedding light on the nature of the progenitor star in the final stages of its life. The study of the environment in the vicinity of the explosion site provides information on a possible relation between these unusual supe...

  9. Asphericity in supernova explosions from late-time spectroscopy.

    Science.gov (United States)

    Maeda, Keiichi; Kawabata, Koji; Mazzali, Paolo A; Tanaka, Masaomi; Valenti, Stefano; Nomoto, Ken'ichi; Hattori, Takashi; Deng, Jinsong; Pian, Elena; Taubenberger, Stefan; Iye, Masanori; Matheson, Thomas; Filippenko, Alexei V; Aoki, Kentaro; Kosugi, George; Ohyama, Youichi; Sasaki, Toshiyuki; Takata, Tadafumi

    2008-02-29

    Core-collapse supernovae (CC-SNe) are the explosions that announce the death of massive stars. Some CC-SNe are linked to long-duration gamma-ray bursts (GRBs) and are highly aspherical. One important question is to what extent asphericity is common to all CC-SNe. Here we present late-time spectra for a number of CC-SNe from stripped-envelope stars and use them to explore any asphericity generated in the inner part of the exploding star, near the site of collapse. A range of oxygen emission-line profiles is observed, including a high incidence of double-peaked profiles, a distinct signature of an aspherical explosion. Our results suggest that all CC-SNe from stripped-envelope stars are aspherical explosions and that SNe accompanied by GRBs exhibit the highest degree of asphericity.

  10. Abundance stratification in Type Ia supernovae - II. The rapidly declining, spectroscopically normal SN2004eo

    Science.gov (United States)

    Mazzali, Paolo A.; Sauer, D. N.; Pastorello, A.; Benetti, S.; Hillebrandt, W.

    2008-06-01

    The variation in properties of Type Ia supernovae, the thermonuclear explosions of Chandrasekhar-mass carbon-oxygen white dwarfs, is caused by different nucleosynthetic outcomes of these explosions, which can be traced from the distribution of abundances in the ejecta. The composition stratification of the spectroscopically normal but rapidly declining SN2004eo is studied by performing spectrum synthesis of a time-series of spectra obtained before and after maximum, and of one nebular spectrum obtained about eight months later. Early-time spectra indicate that the outer ejecta are dominated by oxygen and silicon, and contain other intermediate-mass elements, implying that the outer part of the star was subject only to partial burning. In the inner part, nuclear statistical equilibrium (NSE) material dominates, but the production of 56Ni was limited to ~0.43 +/- 0.05 Msolar. An innermost zone containing ~0.25 Msolar of stable Fe-group material is also present. The relatively small amount of NSE material synthesized by SN2004eo explains both the dimness and the rapidly evolving light curve of this supernova.

  11. Late-Time Photometry of Type Ia Supernova SN2012cg Reveals the Radioactive Decay of $^{57}$Co

    CERN Document Server

    Graur, Or; Shara, Michael M; Riess, Adam G

    2015-01-01

    Seitenzahl et al. (2009) have predicted that $\\sim 3$ years after its explosion, the light we receive from a Type Ia supernova will come mostly from reprocessing of electrons and X-rays emitted by the radioactive decay chain $^{57}{\\rm Co}~\\to~^{57}{\\rm Fe}$, instead of positrons from the decay chain $^{56}{\\rm Co}~\\to~^{56}{\\rm Fe}$ that dominates the supernova light at earlier times. Using the Hubble Space Telescope, we followed the light curve of the Type Ia supernova SN2012cg out to $1055$ days after maximum light. Our measurements are consistent with the light curves predicted by the contribution of energy from the reprocessing of electrons and X-rays emitted by the decay of $^{57}$Co. This provides conclusive evidence that $^{57}$Co is produced in Type Ia supernova explosions. The ratio of luminosities produced by the decays of $^{57}$Co and $^{56}$Co, a strong constraint on any Type Ia supernova explosion model, is in the range $(0.4$ - $8.5)\\times10^{-3}$.

  12. Late-time spectral line formation in Type IIb supernovae, with application to SN 1993J, SN 2008ax, and SN 2011dh

    CERN Document Server

    Jerkstrand, A; Smartt, S J; Fransson, C; Sollerman, J; Taubenberger, S; Bersten, M; Spyromilio, J

    2014-01-01

    We investigate line formation processes in Type IIb supernovae (SNe) from 100 to 500 days post-explosion using spectral synthesis calculations. The modeling identifies the nuclear burning layers and physical mechanisms that produce the major emission lines, and the diagnostic potential of these. We compare the model calculations with data on the three best observed Type IIb SNe to-date - SN 1993J, SN 2008ax, and SN 2011dh. Oxygen nucleosynthesis depends sensitively on the main-sequence mass of the star and modeling of the [O I] 6300, 6364 lines constrains the progenitors of these three SNe to the M_ZAMS=12-16 M_sun range (ejected oxygen masses 0.3-0.9 M_sun), with SN 2011dh towards the lower end and SN 1993J towards the upper end of the range. The high ejecta masses from M_ZAMS >= 17 M_sun progenitors give rise to brighter nebular phase emission lines than observed. Nucleosynthesis analysis thus supports a scenario of low/moderate mass progenitors for Type IIb SNe, and by implication an origin in binary syste...

  13. THE HOST GALAXY OF THE SUPER-LUMINOUS SN 2010gx AND LIMITS ON EXPLOSIVE {sup 56}Ni PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ting-Wan; Smartt, Stephen J.; Kotak, Rubina; McCrum, Matt; Fraser, Morgan [Astrophysics Research Centre, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom); Bresolin, Fabio; Kudritzki, Rolf-Peter [Institute for Astronomy, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Pastorello, Andrea [INAF-Osservatorio Astronomico di Padova, vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Valenti, Stefano [Las Cumbres Observatory Global Telescope Network, Inc., Santa Barbara, CA 93117 (United States)

    2013-02-01

    Super-luminous supernovae have a tendency to occur in faint host galaxies which are likely to have low mass and low metallicity. While these extremely luminous explosions have been observed from z = 0.1 to 1.55, the closest explosions allow more detailed investigations of their host galaxies. We present a detailed analysis of the host galaxy of SN 2010gx (z = 0.23), one of the best studied super-luminous type Ic supernovae. The host is a dwarf galaxy (M{sub g} = -17.42 {+-} 0.17) with a high specific star formation rate. It has a remarkably low metallicity of 12 + log (O/H) = 7.5 {+-} 0.1 dex as determined from the detection of the [O III] {lambda}4363 line. This is the first reliable metallicity determination of a super-luminous stripped-envelope supernova host. We collected deep multi-epoch imaging with Gemini + GMOS between 240 and 560 days after explosion to search for any sign of radioactive {sup 56}Ni, which might provide further insights on the explosion mechanism and the progenitor's nature. We reach griz magnitudes of m{sub AB} {approx} 26, but do not detect SN 2010gx at these epochs. The limit implies that any {sup 56}Ni production was similar to or below that of SN 1998bw (a luminous type Ic SN that produced around 0.4 M{sub Sun} of {sup 56}Ni). The low volumetric rates of these supernovae ({approx}10{sup -4} of the core-collapse population) could be qualitatively matched if the explosion mechanism requires a combination of low-metallicity (below 0.2 Z{sub Sun }), high progenitor mass (>60 M{sub Sun }) and high rotation rate (fastest 10% of rotators).

  14. Neutrino-driven explosions of ultra-stripped type Ic supernovae generating binary neutron stars

    CERN Document Server

    Suwa, Yudai; Shibata, Masaru; Umeda, Hideyuki; Takahashi, Koh

    2015-01-01

    We study explosion characteristics of ultra-stripped supernovae (SNe), which are candidates of SNe generating binary neutron stars (NSs). As a first step, we perform stellar evolutionary simulations of bare carbon-oxygen cores of mass from 1.45 to 2.0 $M_\\odot$ until the iron cores become unstable and start collapsing. We then perform axisymmetric hydrodynamics simulations with spectral neutrino transport using these stellar evolution outcomes as initial conditions. All models exhibit successful explosions driven by neutrino heating. The diagnostic explosion energy, ejecta mass, Ni mass, and NS mass are typically $\\sim 10^{50}$ erg, $\\sim 0.1 M_\\odot$, $\\sim 0.01M_\\odot$, and $\\approx 1.3 M_\\odot$, which are compatible with observations of rapidly-evolving and luminous transient such as SN 2005ek. We also find that the ultra-stripped SN is a candidate for producing the secondary low-mass NS in the observed compact binary NSs like PSR J0737-3039.

  15. SN Refsdal: Classification as a Luminous and Blue SN 1987A-like Type II Supernova

    CERN Document Server

    Kelly, P L; Selsing, J; Foley, R J; Hjorth, J; Rodney, S A; Christensen, L; Strolger, L -G; Filippenko, A V; Treu, T; Steidel, C C; Strom, A; Riess, A G; Zitrin, A; Schmidt, K B; Bradac, M; Jha, S W; Graham, M L; McCully, C; Graur, O; Weiner, B J; Silverman, J M

    2015-01-01

    We have acquired Hubble Space Telescope (HST) and Very Large Telescope near-infrared spectra and images of supernova (SN) Refsdal after its discovery as an Einstein cross in Fall 2014. The HST light curve of SN Refsdal matches the distinctive, slowly rising light curves of SN 1987A-like supernovae (SNe), and we find strong evidence for a broad H-alpha P-Cygni profile in the HST grism spectrum at the redshift (z = 1.49) of the spiral host galaxy. SNe IIn, powered by circumstellar interaction, could provide a good match to the light curve of SN Refsdal, but the spectrum of a SN IIn would not show broad and strong H-alpha absorption. From the grism spectrum, we measure an H-alpha expansion velocity consistent with those of SN 1987A-like SNe at a similar phase. The luminosity, evolution, and Gaussian profile of the H-alpha emission of the WFC3 and X-shooter spectra, separated by ~2.5 months in the rest frame, provide additional evidence that supports the SN 1987A-like classification. In comparison with other exam...

  16. A Wolf-Rayet-like progenitor of supernova SN 2013cu from spectral observations of a wind

    CERN Document Server

    Gal-Yam, Avishay; Ofek, E O; Ben-Ami, S; Cenko, S B; Kasliwal, M M; Cao, Y; Yaron, O; Tal, D; Silverman, J M; Horesh, A; De Cia, A; Taddia, F; Sollerman, J; Perley, D; Vreeswijk, P M; Kulkarni, S R; Nugent, P E; Filippenko, A V; Wheeler, J C

    2014-01-01

    The explosive fate of massive stripped Wolf-Rayet (W-R) stars is a key open question in stellar physics. An appealing option is that hydrogen-deficient W-R stars are the progenitors of some H-poor supernova (SN) explosions of Types IIb, Ib, and Ic. A blue object, having luminosity and colors consistent with those of some W-R stars, has been recently identified at the location of a SN~Ib in pre-explosion images but has not yet been conclusively determined to have been the progenitor. Similar previous works have so far only resulted in nondetections. Comparison of early photometric observations of Type Ic supernovae with theoretical models suggests that the progenitor stars had radii <10^12 cm, as expected for some W-R stars. However, the hallmark signature of W-R stars, their emission-line spectra, cannot be probed by such studies. Here, we report the detection of strong emission lines in an early-time spectrum of SN 2013cu (iPTF13ast; Type IIb) obtained ~15.5 hr after explosion ("flash spectroscopy"). We i...

  17. On the progenitor of SN 2005gl and the nature of Type IIn supernovae

    CERN Document Server

    Gal-Yam, A; Fox, D B; Cenko, S B; Soderberg, A M; Moon, D S; Sand, D J; Li, W; Filippenko, A V; Aldering, G; Copin, Y; Gal-Yam, Avishay

    2006-01-01

    We present a study of the type IIn supernova (SN) 2005gl, in the relatively nearby (d~66 Mpc) galaxy NGC 266. Photometry and spectroscopy of the SN indicate it is a typical member of its class. Pre-explosion Hubble Space Telescope (HST) imaging of the location of the SN, along with a precise localization of this event using the Laser-Guide-Star assisted Adaptive Optics (LGS-AO) system at Keck Observatory, are combined to identify a luminous (M_V=-10.3) point source as the possible progenitor of SN 2005gl. If the source is indeed a single star, it was likely a member of the class of luminous blue variable stars (LBVs). This finding leads us to consider the possible general association of SNe IIn with LBV progenitors. We find this is indeed supported by observations of other SNe, and the known properties of LBV stars. For example, we argue that should the prototypical Galactic LBV eta Carina explode in a phase similar to its current state, it will likely produce a type IIn SN. We discuss our findings in the con...

  18. Neutrino nucleosynthesis in core-collapse Supernova explosions

    Directory of Open Access Journals (Sweden)

    Sieverding A.

    2016-01-01

    Full Text Available The neutrino-induced nucleosynthesis (ν process in supernova explosions of massive stars of solar metallicity with initial main sequence masses between 15 and 40 M⊙ has been studied. A new extensive set of neutrino-nucleus cross-sections for all the nuclei included in the reaction network is used and the average neutrino energies are reduced to agree with modern supernova simulations. Despite these changes the ν process is found to contribute still significantly to the production of the nuclei 7Li, 11B, 19F, 138La and 180Ta, even though the total yields for those nuclei are reduced. Furthermore we study in detail contributions of the ν process to the production of radioactive isotopes 26Al, 22Na and confirm the production of 92Nb and 98Tc.

  19. SN 2009js AT THE CROSSROADS BETWEEN NORMAL AND SUBLUMINOUS TYPE IIP SUPERNOVAE: OPTICAL AND MID-INFRARED EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Gandhi, P. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Yamanaka, M.; Itoh, R. [Department of Physical Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan); Tanaka, M. [National Astronomical Observatory, Mitaka, Tokyo (Japan); Nozawa, T.; Maeda, K.; Moriya, T. J. [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa (Japan); Kawabata, K. S. [Hiroshima Astrophysical Science Center, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Saviane, I. [European Southern Observatory, Alonso de Cordova 3107, Santiago 19 (Chile); Hattori, T. [Subaru Telescope, National Astronomical Observatory of Japan, Hilo, HI 96720 (United States); Sasada, M. [Department of Astronomy, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan)

    2013-04-20

    We present a study of SN 2009js in NGC 918. Multi-band Kanata optical photometry covering the first {approx}120 days shows the source to be a Type IIP SN. Reddening is dominated by that due to our Galaxy. One-year-post-explosion photometry with the New Technology Telescope and a Subaru optical spectrum 16 days post-discovery both imply a good match with the well-studied subluminous SN 2005cs. The plateau-phase luminosity of SN 2009js and its plateau duration are more similar to the intermediate luminosity IIP SN 2008in. Thus, SN 2009js shares characteristics with both subluminous and intermediate luminosity supernovae (SNe). Its radioactive tail luminosity lies between SN 2005cs and SN 2008in, whereas its quasi-bolometric luminosity decline from peak to plateau (quantified by a newly defined parameter {Delta}logL, which measures adiabatic cooling following shock breakout) is much smaller than both the others'. We estimate the ejected mass of {sup 56}Ni to be low ({approx}0.007 M{sub Sun }). The SN explosion energy appears to have been small, similar to that of SN 2005cs. SN 2009js is the first subluminous SN IIP to be studied in the mid-infrared. It was serendipitously caught by Spitzer at very early times. In addition, it was detected by WISE 105 days later with a significant 4.6 {mu}m flux excess above the photosphere. The infrared excess luminosity relative to the photosphere is clearly smaller than that of SN 2004dj, which has been extensively studied in the mid-infrared. The excess may be tentatively assigned to heated dust with mass {approx}3 Multiplication-Sign 10{sup -5} M{sub Sun }, or to CO fundamental emission as a precursor to dust formation.

  20. SN 2012aa: A transient between Type Ibc core-collapse and superluminous supernovae

    Science.gov (United States)

    Roy, R.; Sollerman, J.; Silverman, J. M.; Pastorello, A.; Fransson, C.; Drake, A.; Taddia, F.; Fremling, C.; Kankare, E.; Kumar, B.; Cappellaro, E.; Bose, S.; Benetti, S.; Filippenko, A. V.; Valenti, S.; Nyholm, A.; Ergon, M.; Sutaria, F.; Kumar, B.; Pandey, S. B.; Nicholl, M.; Garcia-Álvarez, D.; Tomasella, L.; Karamehmetoglu, E.; Migotto, K.

    2016-12-01

    Context. Research on supernovae (SNe) over the past decade has confirmed that there is a distinct class of events which are much more luminous (by 2 mag) than canonical core-collapse SNe (CCSNe). These events with visual peak magnitudes ≲-21 are called superluminous SNe (SLSNe). The mechanism that powers the light curves of SLSNe is still not well understood. The proposed scenarios are circumstellar interaction, the emergence of a magnetar after core collapse, or disruption of a massive star through pair production. Aims: There are a few intermediate events which have luminosities between these two classes. They are important for constraining the nature of the progenitors of these two different populations and their environments and powering mechanisms. Here we study one such object, SN 2012aa. Methods: We observed and analysed the evolution of the luminous Type Ic SN 2012aa. The event was discovered by the Lick Observatory Supernova Search in an anonymous galaxy (z ≈ 0.08). The optical photometric and spectroscopic follow-up observations were conducted over a time span of about 120 days. Results: With an absolute V-band peak of - 20 mag, the SN is an intermediate-luminosity transient between regular SNe Ibc and SLSNe. SN 2012aa also exhibits an unusual secondary bump after the maximum in its light curve. For SN 2012aa, we interpret this as a manifestation of SN-shock interaction with the circumstellar medium (CSM). If we assume a 56Ni-powered ejecta, the quasi-bolometric light curve requires roughly 1.3 M⊙ of 56Ni and an ejected mass of 14M⊙. This also implies a high kinetic energy of the explosion, 5.4 × 1051 erg. On the other hand, the unusually broad light curve along with the secondary peak indicate the possibility of interaction with CSM. The third alternative is the presence of a central engine releasing spin energy that eventually powers the light curve over a long time. The host of SN 2012aa is a star-forming Sa/Sb/Sbc galaxy. Conclusions

  1. Lightcurves of Type Ia Supernovae from Near the Time of Explosion

    Energy Technology Data Exchange (ETDEWEB)

    Garg, A; Stubbs, C W; Challis, P; Wood-Vasey, M; Blondin, S; Huber, M E; Cook, K; Nikolaev, S; Rest, A; Smith, R C; Olsen, K; Suntzeff, N B; Aguilera, C; Prieto, J L; Becker, A; Miceli, A; Miknaitis, G; Clocchiatti, A; Minniti, D; Morelli, L; Welch, D

    2006-08-30

    We present a set of 11 type Ia supernova (SN Ia) lightcurves with dense, pre-maximum sampling. These supernovae (SNe), in galaxies behind the Large Magellanic Cloud (LMC), were discovered by the SuperMACHO survey. The SNe span a redshift range of z = 0.11-0.35. Our lightcurves contain some of the earliest pre-maximum observations of SNe Ia to date. We also give a functional model that describes the SN Ia lightcurve shape (in our V R-band). Our function uses the ''expanding fireball'' model of Goldhaber et al. (1998) to describe the rising lightcurve immediately after explosion but constrains it to smoothly join the remainder of the lightcurve. We fit this model to a composite observed V R-band lightcurve of three SNe between redshifts of 0.135 to 0.165. These SNe have not been K-corrected or adjusted to account for reddening. In this redshift range, the observed V R-band most closely matches the rest frame V-band. Using the best fit to our functional description of the lightcurve, we find the time between explosion and observed V R-band maximum to be 19.2 {+-} 1.3-1.6 {+-} 0.07(red.) rest-frame days for a SN Ia with a V R-band {Delta}m{sub -10} of 0.52. For the redshifts sampled, the observed V R-band time-of-maximum brightness should be the same as the rest-frame V -band maximum to within 1.1 rest-frame days.

  2. Optical detection of the radio supernova SN 2000ft in the circumnuclear region of the luminous infrared galaxy NGC 7469

    CERN Document Server

    Colina, L; Alonso-Herrero, A; Panagia, N; Alberdi, A; Torrelles, J M; Wilson, A S

    2007-01-01

    SN 2000ft is detected in two independent Planetary Camera images (F547W and F814W) taken May 13, 2000, about two months before the predicted date of the explosion (July 19, 2000), based on the analysis of its radio light evolution by Alberdi and collaborators. The apparent optical magnitudes and red color of SN 2000ft indicate that it is observed through an extinction of at least A$_V$= 3.0 magnitudes. The extinction corrected lower limit to the absolute visual magnitude (M$_V$ $\\leq -$ 18.0), identifies SN 2000ft as a luminous supernova in the optical, as other luminous radio supernovae before. SN 2000ft exploded in a region located at only 0.1 arcsec (i.e. 34 +/- 3 pc) west of a faint cluster (C24). No parent cluster is identified within the detection limits of the HST short exposures. The unambiguous detection of SN 2000ft in the visual shows that multi-epoch sub-arcsecond (FWHM less than 0.1 arcsec) optical imaging is also a valid tool that should be explored further to detect supernovae in the dusty (cir...

  3. SN2010jp (PTF10aaxi): A Jet-Driven Type II Supernova

    CERN Document Server

    Smith, Nathan; Butler, Nat; Bloom, Joshua S; Kasliwal, Mansi M; Horesh, Assaf; Kulkarni, Shrinivas R; Law, Nicholas M; Nugent, Peter E; Ofek, Eran O; Poznanski, Dovi; Quimby, Robert M; Sesar, Branimir; Ben-Ami, Sagi; Arcavi, Iair; Gal-Yam, Avishay; Polishook, David; Xu, Dong; Yaron, Ofer; Frail, Dale A; Sullivan, Mark

    2011-01-01

    We present photometry and spectroscopy of the peculiar TypeII supernova (SN) 2010jp, also named PTF10aaxi. The light curve exhibits a linear decline with a relatively low peak absolute magnitude of only -15.9, and a low radioactive decay luminosity at late times that suggests a nickel mass below 0.003 $M_{\\odot}$. Spectra of SN2010jp display an unprecedented triple-peaked H$\\alpha$ line profile, showing: (1) a narrow (800 km/s) central component that suggests shock interaction with dense CSM; (2) high-velocity blue and red emission features centered at -12600 and +15400 km/s; and (3) broad wings extending from -22000 to +25000 km/s. These features persist during 100 days after explosion. We propose that this line profile indicates a bipolar jet-driven explosion, with the central component produced by normal SN ejecta and CSM interaction at mid latitudes, while the high-velocity bumps and broad line wings arise in a nonrelativistic bipolar jet. Two variations of the jet interpretation seem plausible: (1) A fas...

  4. The type Iax supernova, SN 2015H: a white dwarf deflagration candidate

    CERN Document Server

    Magee, M R; Sim, S A; Kromer, M; Rabinowitz, D; Smartt, S J; Baltay, C; Campbell, H C; Chen, T -W; Fink, M; Gal-Yam, A; Galbany, L; Hillebrandt, W; Inserra, C; Kankare, E; Guillou, L Le; Lyman, J D; Maguire, K; Ruiter, A J; Seitenzahl, I R; Sullivan, M; Valenti, S; Young, D R

    2016-01-01

    We present results based on observations of SN 2015H which belongs to the small group of objects similar to SN 2002cx, otherwise known as type Iax supernovae. The availability of deep pre-explosion imaging allowed us to place tight constraints on the explosion epoch. Our observational campaign began approximately one day post-explosion, and extended over a period of about 150 days post maximum light, making it one of the best observed objects of this class to date. We find a peak magnitude of M$_r$ = -17.27 $\\pm$ 0.07, and a ($\\Delta m_{15})_r$ = 0.69 $\\pm$ 0.04. Comparing our observations to synthetic spectra generated from simulations of deflagrations of Chandrasekhar mass carbon-oxygen white dwarfs, we find reasonable agreement with models of weak deflagrations that result in the ejection of ~0.2 M$_{\\odot}$ of material containing ~0.07 M$_{\\odot}$ of 56Ni. The model light curve however, evolves more rapidly than observations, suggesting that a higher ejecta mass is to be favoured. Nevertheless, empirical ...

  5. Neutron Star Kicks by the Gravitational Tug-boat Mechanism in Asymmetric Supernova Explosions: Progenitor and Explosion Dependence

    Science.gov (United States)

    Janka, Hans-Thomas

    2017-03-01

    Asymmetric mass ejection in the early phase of supernova (SN) explosions can impart a kick velocity to the new-born neutron star (NS). For neutrino-driven explosions the NS acceleration has been shown to be mainly caused by the gravitational attraction of the anisotropically expelled inner ejecta, while hydrodynamic forces contribute on a subdominant level, and asymmetric neutrino emission plays only a secondary role. Two- and three-dimensional hydrodynamic simulations have demonstrated that this gravitational tug-boat mechanism can explain the observed space velocities of young NSs up to more than 1000 km s‑1. Here, we discuss how the NS kick depends on the energy, ejecta mass, and asymmetry of the SN explosion, and what role the compactness of the pre-collapse stellar core plays for the momentum transfer to the NS. We also provide simple analytic expressions for the NS velocity in terms of these quantities. Referring to results of hydrodynamic simulations in the literature, we argue why, within the discussed scenario of NS acceleration, electron-capture SNe, low-mass Fe-core SNe, and ultra-stripped SNe can be expected to have considerably lower intrinsic NS kicks than core-collapse SNe of massive stellar cores. Our basic arguments also remain valid if progenitor stars possess large-scale asymmetries in their convective silicon and oxygen burning layers. Possible scenarios for spin-kick alignment are sketched. Much of our discussion stays on a conceptual and qualitative level, and more work is necessary on the numerical modeling side to determine the dependences of involved parameters, whose prescriptions will be needed for recipes that can be used to better describe NS kicks in binary evolution and population synthesis studies.

  6. SN 2013ej IN M74: A LUMINOUS AND FAST-DECLINING TYPE II-P SUPERNOVA

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Fang [Department of Astronomy, Beijing Normal University, Beijing 100875 (China); Wang, Xiaofeng; Chen, Juncheng; Mo, Jun; Zhao, Xulin [Physics Department and Tsinghua Center for Astrophysics, Tsinghua University, Beijing 100084 (China); Zhang, Jujia [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Brown, Peter J. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A. and M. University, Department of Physics and Astronomy, 4242 TAMU, College Station, TX 77843 (United States); Zampieri, Luca [INAF-Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova (Italy); Pumo, Maria Letizia [INAF-Osservatorio Astronomico di Palermo “Giuseppe S. Vaiana,” Piazza del Parlamento 1, I-90134 Palermo (Italy); Zhang, Tianmeng, E-mail: huangfang@mail.bnu.edu.cn, E-mail: wang_xf@mail.tsinghua.edu.cn [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2015-07-01

    We present extensive ultraviolet, optical, and near-infrared observations of the Type IIP supernova (SN IIP) 2013ej in the nearby spiral galaxy M74. The multicolor light curves, spanning from ∼8–185 days after explosion, show that it has a higher peak luminosity (i.e., M{sub V} ∼ −17.83 mag at maximum light), a faster post-peak decline, and a shorter plateau phase (i.e., ∼50 days) compared to the normal Type IIP SN 1999em. The mass of {sup 56}Ni is estimated as 0.02 ± 0.01 M{sub ⊙} from the radioactive tail of the bolometric light curve. The spectral evolution of SN 2013ej is similar to that of SN 2004et and SN 2007od, but shows a larger expansion velocity (i.e., v{sub Fe} {sub ii} ∼ 4600 km s{sup −1} at t ∼ 50 days) and broader line profiles. In the nebular phase, the emission of the Hα line displays a double-peak structure, perhaps due to the asymmetric distribution of {sup 56}Ni produced in the explosion. With the constraints from the main observables such as bolometric light curve, expansion velocity, and photospheric temperature of SN 2013ej, we performed hydrodynamical simulations of the explosion parameters, yielding the total explosion energy as ∼0.7× 10{sup 51} erg, the radius of the progenitor as ∼600 R{sub ⊙}, and the ejected mass as ∼10.6 M{sub ⊙}. These results suggest that SN 2013ej likely arose from a red supergiant with a mass of 12–13 M{sub ⊙} immediately before the explosion.

  7. Type Iax Supernovae: A New Class of Stellar Explosion

    DEFF Research Database (Denmark)

    Foley, Ryan J.; Challis, P. J.; Chornock, R.

    2013-01-01

    We describe observed properties of the Type Iax class of supernovae (SNe Iax), consisting of SNe observationally similar to its prototypical member, SN 2002cx. The class currently has 25 members, and we present optical photometry and/or optical spectroscopy for most of them. SNe Iax are spectrosc......We describe observed properties of the Type Iax class of supernovae (SNe Iax), consisting of SNe observationally similar to its prototypical member, SN 2002cx. The class currently has 25 members, and we present optical photometry and/or optical spectroscopy for most of them. SNe Iax...... are spectroscopically similar to SNe Ia, but have lower maximum-light velocities (2000 M_V,peak > -18.9 mag), and most have hot photospheres. Relative to SNe Ia, SNe Iax have low luminosities for their light-curve shape. There is a correlation between...... luminosity and light-curve shape, similar to that of SNe Ia, but offset from that of SNe Ia and with larger scatter. Despite a host-galaxy morphology distribution that is highly skewed to late-type galaxies without any SNe Iax discovered in elliptical galaxies, there are several indications...

  8. An Integral Condition for Core-collapse Supernova Explosions

    Science.gov (United States)

    Murphy, Jeremiah W.; Dolence, Joshua C.

    2017-01-01

    We derive an integral condition for core-collapse supernova (CCSN) explosions and use it to construct a new diagnostic of explodability. The fundamental challenge in CCSN theory is to explain how a stalled accretion shock revives to explode a star. In this manuscript, we assume that the shock revival is initiated by the delayed-neutrino mechanism and derive an integral condition for spherically symmetric shock expansion, vs > 0. One of the most useful one-dimensional explosion conditions is the neutrino luminosity and mass-accretion rate ({L}ν {--}\\dot{{ M }}) critical curve. Below this curve, steady-state stalled solutions exist, but above this curve, there are no stalled solutions. Burrows & Goshy suggested that the solutions above this curve are dynamic and explosive. In this manuscript, we take one step closer to proving this supposition; we show that all steady solutions above this curve have vs > 0. Assuming that these steady vs > 0 solutions correspond to explosion, we present a new dimensionless integral condition for explosion, Ψ > 0. Ψ roughly describes the balance between pressure and gravity, and we show that this parameter is equivalent to the τ condition used to infer the {L}ν {--}\\dot{{ M }} critical curve. The illuminating difference is that there is a direct relationship between Ψ and vs. Below the critical curve, Ψ may be negative, positive, and zero, which corresponds to receding, expanding, and stalled-shock solutions. At the critical curve, the minimum Ψ solution is zero; above the critical curve, Ψmin > 0, and all steady solutions have vs > 0. Using one-dimensional simulations, we confirm our primary assumptions and verify that Ψmin > 0 is a reliable and accurate explosion diagnostic.

  9. Superluminous supernova 2015bn in the nebular phase: evidence for the engine-powered explosion of a stripped massive star

    CERN Document Server

    Nicholl, M; Margutti, R; Chornock, R; Blanchard, P K; Jerkstrand, A; Smartt, S J; Arcavi, I; Challis, P; Chambers, K C; Chen, T -W; Cowperthwaite, P S; Gal-Yam, A; Hosseinzadeh, G; Howell, D A; Inserra, C; Kankare, E; Magnier, E A; Maguire, K; Mazzali, P A; McCully, C; Milisavljevic, D; Smith, K W; Taubenberger, S; Valenti, S; Wainscoat, R J; Yaron, O; Young, D R

    2016-01-01

    We present nebular-phase imaging and spectroscopy for the hydrogen-poor superluminous supernova SN 2015bn, at redshift z=0.1136, spanning +250-400 d after maximum light. The light curve exhibits a steepening in the decline rate from 1.4 mag/(100 d) to 1.7 mag/(100 d), suggestive of a significant decrease in the opacity. This change is accompanied by a transition from a blue continuum superposed with photospheric absorption lines to a nebular spectrum dominated by emission lines of oxygen, calcium and magnesium. There are no obvious signatures of circumstellar interaction or large nickel mass. We show that the spectrum at +400 d is virtually identical to a number of energetic Type Ic supernovae such as SN 1997dq, SN 2012au, and SN 1998bw, indicating similar core conditions and strengthening the link between `hypernovae'/long gamma-ray bursts and superluminous supernovae. A single explosion mechanism may unify these events that span absolute magnitudes of -22 < M_B < -17. Both the light curve and spectrum...

  10. Constraints on the Progenitor System of the Type Ia Supernova 2014J from Pre-Explosion Hubble Space Telescope Imaging

    Science.gov (United States)

    Kelly, Patrick L.; Fox, Ori D.; Filippenko, Alexei V.; Cenko, S. Bradley; Prato, Lisa; Schaefer, Gail; Shen, Ken J.; Zheng, WeiKang; Graham, Melissa L.; Tucker, Brad E.

    2014-01-01

    We constrain the properties of the progenitor system of the highly reddened Type Ia supernova (SN Ia) 2014J in Messier 82 (M82; d (is) approx. 3.5 Mpc). We determine the supernova (SN) location using Keck-II K-band adaptive optics images, and we find no evidence for flux from a progenitor system in pre-explosion near-ultraviolet through near-infrared Hubble Space Telescope (HST) images. Our upper limits exclude systems having a bright red giant companion, including symbiotic novae with luminosities comparable to that of RS Ophiuchi. While the flux constraints are also inconsistent with predictions for comparatively cool He-donor systems (T (is) approximately 35,000 K), we cannot preclude a system similar to V445 Puppis. The progenitor constraints are robust across a wide range of RV and AV values, but significantly greater values than those inferred from the SN light curve and spectrum would yield proportionally brighter luminosity limits. The comparatively faint flux expected from a binary progenitor system consisting of white dwarf stars would not have been detected in the pre-explosion HST imaging. Infrared HST exposures yield more stringent constraints on the luminosities of very cool (T (is) less than 3000 K) companion stars than was possible in the case of SN Ia 2011fe.

  11. Polarization spectral synthesis for Type Ia supernova explosion models

    Science.gov (United States)

    Bulla, M.; Sim, S. A.; Kromer, M.

    2015-06-01

    We present a Monte Carlo radiative transfer technique for calculating synthetic spectropolarimetry for multidimensional supernova explosion models. The approach utilizes `virtual-packets' that are generated during the propagation of the Monte Carlo quanta and used to compute synthetic observables for specific observer orientations. Compared to extracting synthetic observables by direct binning of emergent Monte Carlo quanta, this virtual-packet approach leads to a substantial reduction in the Monte Carlo noise. This is not only vital for calculating synthetic spectropolarimetry (since the degree of polarization is typically very small) but also useful for calculations of light curves and spectra. We first validate our approach via application of an idealized test code to simple geometries. We then describe its implementation in the Monte Carlo radiative transfer code ARTIS and present test calculations for simple models for Type Ia supernovae. Specifically, we use the well-known one-dimensional W7 model to verify that our scheme can accurately recover zero polarization from a spherical model, and to demonstrate the reduction in Monte Carlo noise compared to a simple packet-binning approach. To investigate the impact of aspherical ejecta on the polarization spectra, we then use ARTIS to calculate synthetic observables for prolate and oblate ellipsoidal models with Type Ia supernova compositions.

  12. Supernova explosions and the birth of neutron stars

    CERN Document Server

    Janka, H -Th; Müller, B; Scheck, L

    2007-01-01

    We report here on recent progress in understanding the birth conditions of neutron stars and the way how supernovae explode. More sophisticated numerical models have led to the discovery of new phenomena in the supernova core, for example a generic hydrodynamic instability of the stagnant supernova shock against low-mode nonradial deformation and the excitation of gravity-wave activity in the surface and core of the nascent neutron star. Both can have supportive or decisive influence on the inauguration of the explosion, the former by improving the conditions for energy deposition by neutrino heating in the postshock gas, the latter by supplying the developing blast with a flux of acoustic power that adds to the energy transfer by neutrinos. While recent two-dimensional models suggest that the neutrino-driven mechanism may be viable for stars from about 8 solar masses to at least 15 solar masses, acoustic energy input has been advocated as an alternative if neutrino heating fails. Magnetohydrodynamic effects ...

  13. The Type II supernovae 2006V and 2006au: two SN 1987A-like events

    DEFF Research Database (Denmark)

    Taddia, F.; Stritzinger, M. D.; Sollerman, J.

    2012-01-01

    Context. Supernova 1987A revealed that a blue supergiant (BSG) star can end its life as a core-collapse supernova (SN). SN 1987A and other similar objects exhibit properties that distinguish them from ordinary Type II Plateau (IIP) SNe, whose progenitors are believed to be red supergiants (RSGs)....

  14. Light-curve Analysis of Ordinary Type IIP Supernovae Based on Neutrino-driven Explosion Simulations in Three Dimensions

    Science.gov (United States)

    Utrobin, V. P.; Wongwathanarat, A.; Janka, H.-Th.; Müller, E.

    2017-09-01

    Type II-plateau supernovae (SNe IIP) are the most numerous subclass of core-collapse SNe originating from massive stars. In the framework of the neutrino-driven explosion mechanism, we study the properties of the SN outburst for a red supergiant progenitor model and compare the corresponding light curves with observations of the ordinary Type IIP SN 1999em. Three-dimensional (3D) simulations of (parametrically triggered) neutrino-driven explosions are performed with the (explicit, finite-volume, Eulerian, multifluid hydrodynamics) code Prometheus, using a presupernova model of a 15 M ⊙ star as initial data. On approaching homologous expansion, the hydrodynamic and composition variables of the 3D models are mapped to a spherically symmetric configuration, and the simulations are continued with the (implicit, Lagrangian, radiation hydrodynamics) code Crab to follow the evolution of the blast wave during the SN outburst. Our 3D neutrino-driven explosion model with an explosion energy of about 0.5× {10}51 erg produces 56Ni in rough agreement with the amount deduced from fitting the radioactively powered light-curve tail of SN 1999em. The considered presupernova model, 3D explosion simulations, and light-curve calculations can explain the basic observational features of SN 1999em, except for those connected to the presupernova structure of the outer stellar layers. Our 3D simulations show that the distribution of 56Ni-rich matter in velocity space is asymmetric with a strong dipole component that is consistent with the observations of SN 1999em. The monotonic decline in luminosity from the plateau to the radioactive tail in ordinary SNe IIP is a manifestation of the intense turbulent mixing at the He/H composition interface.

  15. Astronomers Make "Movie" of Radio Images Showing Supernova Explosion

    Science.gov (United States)

    1995-11-01

    - dispersed radio telescopes has existed for only a few years. Supernova 1993J was the first one that was both close enough and had radio emission strong enough to enable scientists to make such detailed images. While the circular images show that the explosion debris is expanding symmetrically, the radio emission is stronger on one side of the shell. The explanation for this is unclear. Some astronomers have suggested that the stronger emission could result from the debris interacting with a companion star orbiting the one that exploded. The researchers believe that their sequence of images, with the stronger emission persisting for months after the explosion, makes the companion-star hypothesis unlikely. Previous radio observations of older and larger supernova shells have revealed protrusions within the shell. The latest images, however, show no such protrusions. This places limits on theories of how the protrusions form. In addition, the new images show that Supernova 1993J's debris shell has shown no signs yet of slowing due to interaction with material surrounding it. The material from the star's explosion is moving at nearly 10,000 miles per second, according to the researchers. At that speed, the material would travel the distance from the Earth to Saturn in one day. When the angular expansion rate of the supernova debris measured by the radio observatories is combined with the expansion speed of the same debris, measured by optical astronomers, it is possible to obtain an accurate value of the distance to M81. The value determined, 11 million light-years, is similar to that obtained by other, independent, means. This is important, as astronomers continue to seek more accurate distances to celestial objects to better gauge the actual size of the Universe. In addition to the VLA and several antennas of the VLBA, the scientists used German and Italian radio telescopes, as well as NASA facilities in California and Spain.

  16. Sn 2008in - bridging the gap between normal and faint supernovae of type IIP

    CERN Document Server

    Roy, Rupak; Benetti, Stefano; Pastorello, Andrea; Yuan, Fang; Brown, Peter J; Immler, Stefan; Fatkhullin, Timur A; Moskvitin, Alexander S; Maund, Justyn; Akerlof, Carl W; Wheeler, J Craig; Sokolov, Vladimir V; Quimby, Rorbert M; Bufano, Filomena; Kumar, Brajesh; Misra, Kuntal; Pandey, S B; Elias-Rosa, Nancy; Roming, Peter W A; Sagar, Ram

    2011-01-01

    We present optical photometric and low-resolution spectroscopic observations of the Type II plateau supernova (SN) 2008in, which occurred in the outskirts of the nearly face-on spiral galaxy M 61. Photometric data in the X-rays, ultraviolet and near-infrared bands have been used to characterize this event. The SN field was imaged with the ROTSE-IIIb optical telescope about seven days before the explosion. This allowed us to constrain the epoch of the shock breakout to JD = 2454825.6. The duration of the plateau phase, as derived from the photometric monitoring, was ~ 98 days. The spectra of SN 2008in show a striking resemblance to those of the archetypal low-luminosity IIP SNe 1997D and 1999br. A comparison of ejecta kinematics of SN 2008in with the hydrodynamical simulations of Type IIP SNe by Dessart et al. (2010) indicates that it is a less energetic event (~ 5$\\times10^{50}$ erg). However, the light curve indicates that the production of radioactive $^{56}$Ni is significantly higher than that in the low-l...

  17. UV-Optical Observation of Type Ia Supernova SN 2013dy in NGC 7250

    CERN Document Server

    Zhai, Qian; Wang, XiaoFeng; Zhang, TianMeng; Liu, ZhengWei; Brown, Peter J; Huang, Fan; Zhao, XuLin; Chang, Liang; Yi, WeiMin; Wang, ChuanJun; Xin, YuXin; Wang, JianGuo; Lun, BaoLi; Zhang, XiLiang; Fan, YuFeng; Zheng, XiangMing; Bai, JinMing

    2016-01-01

    Extensive and independent observations of Type Ia supernova (SN Ia) SN 2013dy are presented, including a larger set of $UBVRI$ photometry and optical spectra since a few days before the peak brightness to $\\sim$ 200 days after explosion, and ultraviolet (UV) photometry spanning from $t \\approx -10$ days to $t \\approx +15$ days referring to the $B$ band maximum. The peak brightness (i.e., $M_{\\rm B} = -19.65 \\pm 0.40$ mag, $L_{\\rm max} = [1.95 \\pm 0.55] \\times 10^{43}$ erg s$^{-1}$) and the mass of synthesised $^{56}$Ni (i.e., $M$($^{56}$Ni) = 0.90 $\\pm$ 0.26 M$_{\\sun}$) are calculated, which conform to the expectation of the slow decline rate (i.e., \\DR = 0.90 $\\pm$ 0.03 mag, Phillip 1993). However, the near infrared (NIR) brightness of this SN (i.e., $M_{\\rm H} = -17.33 \\pm 0.30$ mag) is at least 1.0 mag fainter than usual. Besides, spectroscopy classification reveals that SN 2013dy resides on the border of "core-normal" and "shallow silicon" subclasses in the Branch et al. (2009) classification scheme, or o...

  18. The explosion mechanism of core-collapse supernovae: progress in supernova theory and experiments

    CERN Document Server

    Foglizzo, Thierry; Guilet, Jérôme; Masset, Frédéric; González, Matthias; Krueger, Brendan K; Novak, Jérôme; Oertel, Micaela; Margueron, Jérôme; Faure, Julien; Martin, Noël; Blottiau, Patrick; Peres, Bruno; Durand, Gilles

    2015-01-01

    The explosion of core-collapse supernova depends on a sequence of events taking place in less than a second in a region of a few hundred kilometers at the center of a supergiant star, after the stellar core approaches the Chandrasekhar mass and collapses into a proto-neutron star, and before a shock wave is launched across the stellar envelope. Theoretical efforts to understand stellar death focus on the mechanism which transforms the collapse into an explosion. Progress in understanding this mechanism is reviewed with particular attention to its asymmetric character. We highlight a series of successful studies connecting observations of supernova remnants and pulsars properties to the theory of core-collapse using numerical simulations. The encouraging results from first principles models in axisymmetric simulations is tempered by new puzzles in 3D. The diversity of explosion paths and the dependence on the pre-collapse stellar structure is stressed, as well as the need to gain a better understanding of hydr...

  19. A Swift Look at SN 2011fe: The Earliest Ultraviolet Observations of a Type Ia Supernova

    Science.gov (United States)

    Oates, Samantha; Holland, Stephen; Immler, Stefan; Brown, Peter J.; Dawson, Kyle S.; DePasquale, Massimiliano; Gronwall, Caryl; Kuin, Paul; Mazzali, Paolo; Miline, Peter; Siegel, Michael

    2012-01-01

    We present the earliest ultraviolet (UV) observations of the bright Type Ia supernova SN 2011fe/PTF11kly in the nearby galaxy M101 at a distance of only 6.4 Mpc. It was discovered shortly after explosion by the Palomar Transient Factory and first observed by Swift/UVOT about a day after explosion. The early UV light is well-defined, with approx. 20 data points per filter in the 5 days after explosion. With these early UV observations, we extend the near-UV template of SNe Ia to earlier times for comparison with observations at low and high redshift and report fits from semiempirical models of the explosion. We find the early UV count rates to be well fit by the superposition of two parabolic curves. Finally, we use the early UV flux measurements to examine a possible shock interaction with a non-degenerate companion. We find that even a solar mass companion at a distance of a few solar radii is unlikely at more than 95% confidence.

  20. MERLIN radio observations of two recent supernovae in Arp299: SN2010O & SN2010P

    Science.gov (United States)

    Beswick, R. J.; Perez-Torres, M. A.; Mattila, S.; Garrington, S. T.; Kankare, E.; Ryder, S.; Alberdi, A.; Romero-Canizales, C.

    2010-02-01

    We report MERLIN radio observations of the two recent supernovae in Arp299; SN2010P and SN2010O (CBET #2145 and CBET #2144, respectively). Observations of Arp299 were made between 1900UT 29th Jan 2010 and 0150UT 1st Feb 2010 at 4994MHz. The previously known compact radio structure of Arp299, including the nuclear starburst components associated with A=IC694 and B1=the southernmost nucleus of NGC3690 are detected (Neff, Ulvestad & Teng 2004, ApJ, 611, 186; Ulvestad 2009 AJ, 138, 152; Perez-Torres et al 2009, A&A 507, 17).

  1. Stellar Forensics VI: A post-explosion view of the progenitor of SN 2012aw

    Science.gov (United States)

    Maund, Justyn

    2014-10-01

    Recent studies have used high spatial resolution HST observations of supernova (SN) sites to directly identify the progenitors of core-collapse SNe in pre-explosion images. These studies have set constraints about the nature of massive stars and their evolution just prior to explosion. Now, at late-times when the SNe have faded sufficiently, it is possible to return to the sites of these core-collapse SNe to search for clues about the nature of their progenitors.We request time to conduct deep, late-time, high-resolution imaging with ACS/WFC of the site of the core-collapse SN 2012aw. We aim to: 1) Confirm our original identification, made in pre-explosion images, by confirming that the progenitor is now missing; 2) Apply image subtraction techniques for this late-time imaging with our pre-explosion images to determine accurate photometry of the progenitor to constrain the temperature and luminosity. HST provides the unique combination of high-resolution optical imaging at very faintmagnitudes that will facilitate this study.

  2. Explosive nucleosynthesis in the neutrino-driven aspherical supernova explosion of a non-rotating 15$M_{\\odot}$ star with solar metallicity

    CERN Document Server

    Fujimoto, Shin-ichiro; Hashimoto, Masa-aki; Ono, Masaomi; Ohnishi, Naofumi

    2011-01-01

    We investigate explosive nucleosynthesis in a non-rotating 15$M_\\odot$ star with solar metallicity that explodes by a neutrino-heating supernova (SN) mechanism aided by both standing accretion shock instability (SASI) and convection. To trigger explosions in our two-dimensional hydrodynamic simulations, we approximate the neutrino transport with a simple light-bulb scheme and systematically change the neutrino fluxes emitted from the protoneutron star. By a post-processing calculation, we evaluate abundances and masses of the SN ejecta for nuclei with the mass number $\\le 70$ employing a large nuclear reaction network. Aspherical abundance distributions, which are observed in nearby core-collapse SN remnants, are obtained for the non-rotating spherically-symmetric progenitor, due to the growth of low-mode SASI. Abundance pattern of the supernova ejecta is similar to that of the solar system for models whose masses ranges $(0.4-0.5) \\Ms$ of the ejecta from the inner region ($\\le 10,000\\km$) of the precollapse ...

  3. Supernova 2007bi as a pair-instability explosion

    CERN Document Server

    Gal-Yam, A; Ofek, E O; Nugent, P E; Kulkarni, S R; Kasliwal, M M; Quimby, R M; Filippenko, A V; Cenko, S B; Chornock, R; Waldman, R; Kasen, D; Sullivan, M; Beshore, E C; Drake, A J; Thomas, R C; Bloom, J S; Poznanski, D; Miller, A A; Foley, R J; Silverman, J M; Arcavi, I; Ellis, R S; Deng, J

    2010-01-01

    Stars with initial masses 10 M_{solar} 140 M_{solar}), if such exist, have oxygen cores which exceed M_{core} = 50 M_{solar}. There, high temperatures are reached at relatively low densities. Conversion of energetic, pressure-supporting photons into electron-positron pairs occurs prior to oxygen ignition, and leads to a violent contraction that triggers a catastrophic nuclear explosion. Tremendous energies (>~ 10^{52} erg) are released, completely unbinding the star in a pair-instability SN (PISN), with no compact remnant. Transitional objects with 100 M_{solar} 3 M_{solar} of ra dioactive 56Ni were synthesized, and that our observations are well fit by PISN models. A PISN explosion in the local Universe indicates that nearby dwarf galaxies probably host extremely massive stars, above the apparent Galactic limit, perhaps resulting from star formation processes similar to those that created the first stars in the Universe.

  4. Role of Nucleon Strangeness in Core-Collapse Supernova Explosions

    Science.gov (United States)

    Hobbs, Timothy; Alberg, Mary; Miller, Gerald

    2016-09-01

    The ongoing quest to simulate explosions of core-collapse supernovae (CCSNe) in hydrodynamical calculations has placed an enormous premium upon the nuclear and hadronic processes integral to the system's evolution (i.e., the microphysics). In this context, modifications to the neutrino-nucleon elastic cross section have been identified as potentially key to ensuring that stalled bounce shocks are sufficiently re-energized to produce the desired explosion. An important source of such corrections can be found in a negative value for the nucleon's strange helicity content Δs , which leads to the enhancement and suppression of the ν - p and ν - n total cross sections, respectively. In this talk, however, I summarize the results of a recent analysis which led to a comparatively small magnitude for the strange helicity (Δs >= - 0 . 1) - a fact which renders nucleon strangeness an unlikely candidate for the decisive missing ingredient necessary in simulations for CCSN explosions. Work supported by DOE Office of Science, Office of Basic Energy Sciences program under Award No. DE-FG02-97ER-41014, and NSF Grant No. 1205686.

  5. THREE-DIMENSIONAL EXPLOSION GEOMETRY OF STRIPPED-ENVELOPE CORE-COLLAPSE SUPERNOVAE. I. SPECTROPOLARIMETRIC OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Masaomi; Iye, Masanori [National Astronomical Observatory, Mitaka, Tokyo (Japan); Kawabata, Koji S.; Yamanaka, Masayuki [Hiroshima Astrophysical Science Center, Hiroshima University, Higashi-Hiroshima, Hiroshima (Japan); Hattori, Takashi; Aoki, Kentaro; Sasaki, Toshiyuki [Subaru Telescope, National Astronomical Observatory of Japan, Hilo, HI 96720 (United States); Mazzali, Paolo A. [Max-Planck Institut fuer Astrophysik, Karl-Schwarzschild-Strasse 2 D-85748 Garching bei Muenchen (Germany); Maeda, Keiichi; Nomoto, Ken' ichi [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa (Japan); Pian, Elena, E-mail: masaomi.tanaka@nao.ac.jp [Istituto Naz. di Astrofisica-Oss. Astron., Via Tiepolo, 11, 34131 Trieste (Italy)

    2012-07-20

    We study the multi-dimensional geometry of supernova (SN) explosions by means of spectropolarimetric observations of stripped-envelope SNe, i.e., SNe without a hydrogen-rich layer. We perform spectropolarimetric observations of two stripped-envelope SNe, Type Ib SN 2009jf and Type Ic SN 2009mi. Both objects show non-zero polarization at the wavelength of the strong lines. They also show a loop in the Stokes Q - U diagram, which indicates a non-axisymmetric, three-dimensional ion distribution in the ejecta. We show that five out of six stripped-envelope SNe, which have been observed spectropolarimetrically so far, show such a loop. This implies that a three-dimensional geometry is common in stripped-envelope SNe. We find that stronger lines tend to show higher polarization. This effect is not related to the geometry, and must be corrected for to compare the polarization of different lines or different objects. Even after the correction, however, there remains a dispersion of polarization degree among different objects. Such a dispersion might be caused by three-dimensional clumpy ion distributions viewed from different directions.

  6. Three-Dimensional Explosion Geometry of Stripped-Envelope Core-Collapse Supernovae. I. Spectropolarimetric Observations

    CERN Document Server

    Tanaka, Masaomi; Hattori, Takashi; Mazzali, Paolo A; Aoki, Kentaro; Iye, Masanori; Maeda, Keiichi; Nomoto, Ken'ichi; Pian, Elena; Sasaki, Toshiyuki; Yamanaka, Masayuki

    2012-01-01

    We study the multi-dimensional geometry of supernova (SN) explosions by means of spectropolarimetric observations of stripped-envelope SNe, i.e., SNe without a H-rich layer. We perform spectropolarimetric observations of 2 stripped-envelope SNe, the Type Ib SN 2009jf and the Type Ic SN 2009mi. Both objects show non-zero polarization at the wavelength of the strong lines. They also show a loop in the Stokes Q-U diagram, which indicates a non-axisymmetric, three-dimensional ion distribution in the ejecta. We show that five out of six stripped-envelope SNe which have been observed spectropolarimetrically so far show such a loop. This implies that a three-dimensional geometry is common in stripped-envelope SNe. We find that stronger lines tend to show higher polarization. This effect is not related to the geometry, and must be corrected to compare the polarization of different lines or different objects. Even after the correction, however, there remains a dispersion of polarization degree among different objects....

  7. A relativistic neutron fireball from a supernova explosion as a possible source of chiral influence.

    Science.gov (United States)

    Gusev, G A; Saito, T; Tsarev, V A; Uryson, A V

    2007-06-01

    We elaborate on a previously proposed idea that polarized electrons produced from neutrons, released in a supernova (SN) explosion, can cause chiral dissymmetry of molecules in interstellar gas-dust clouds. A specific physical mechanism of a relativistic neutron fireball with Lorentz factor of the order of 100 is assumed for propelling a great number of free neutrons outside the dense SN shell. A relativistic chiral electron-proton plasma, produced from neutron decays, is slowed down owing to collective effects in the interstellar plasma. As collective effects do not involve the particle spin, the electrons can carry their helicities to the cloud. The estimates show high chiral efficiency of such electrons. In addition to this mechanism, production of circularly polarized ultraviolet photons through polarized-electron bremsstrahlung at an early stage of the fireball evolution is considered. It is shown that these photons can escape from the fireball plasma. However, for an average density of neutrals in the interstellar medium of the order of 0.2 cm(-3) and at distances of the order of 10 pc from the SN, these photons will be absorbed with a factor of about 10(-7) due to the photoeffect. In this case, their chiral efficiency will be about five orders of magnitude less than that for polarized electrons.

  8. A Luminous Peculiar Type Ia Supernova SN 2011hr: More Like SN 1991T or SN 2007if?

    CERN Document Server

    Zhang, Jujia; Sasdelli, Michele; Zhang, Tianmeng; Liu, Zhengweei; Mazzali, Paolo A; Meng, Xiangcun; Maeda, Keiichi; Chen, Juncheng; Huang, Fang; Zhao, Xulin; Zhang, Kaicheng; Zhai, Qian; Pian, Elena; Wang, Bo; Chang, Liang; Yi, Weimin; Wang, Chuan-Jun; Wang, Xueli; Xin, Yuxin; Wang, Jianguo; Lun, Baoli; Zheng, Xiangming; Zhang, Xiliang; Fan, Yufeng; Bai, Jinming

    2015-01-01

    Photometric and spectroscopic observations of a slowly declining, luminous type Ia supernova (SN Ia) 2011hr in the star-burst galaxy NGC 2691 are presented. SN~2011hr is found to peak at $M_{B}=-19.84 \\pm 0.40\\,\\rm{mag}$, with a post-maximum decline rate $\\Delta$m$_{15}$(B) = 0.92 $\\pm$ 0.03\\,$\\rm{mag}$. From the maximum-light bolometric luminosity, $L=(2.30 \\pm 0.90) \\times 10^{43}\\,\\rm{erg\\,s^{-1}}$, we estimate the mass of synthesized \\Nifs\\ in SN~2011hr to be $M(\\rm{^{56}Ni})=1.11 \\pm 0.43\\,M_{\\sun}$. SN 2011hr appears more luminous than SN 1991T at around maximum light, and the absorption features from its intermediate-mass elements (IMEs) are noticeably weaker than the latter at similar phases. Spectral modelling suggests that SN 2011hr has the IMEs of $\\sim$\\,0.07 M$_{\\sun}$ in the outer ejecta, which is much lower than the typical value of normal SNe Ia (i.e., 0.3 -- 0.4 M$_{\\sun}$) and is also lower than the value of SN 1991T (i.e., $\\sim$\\,0.18 M$_{\\sun}$). These results indicate that SN~2011hr may ...

  9. Optical and near infrared coverage of SN 2004et: physical parameters and comparison with other type IIP supernovae

    CERN Document Server

    Maguire, K; Smartt, S J; Pastorello, A; Tsvetkov, D Yu; Benetti, S; Spiro, S; Arkharov, A A; Beccari, G; Botticella, M T; Cappellaro, E; Cristallo, S; Dolci, M; Elias-Rosa, N; Fiaschi, M; D., Gorshanov; Harutyunyan, A; Larionov, V M; Navasardyan, H; Pietrinferni, A; Raimondo, G; Di Rico, G; Valenti, S; Valentini, G; Zampieri, L

    2009-01-01

    We present new optical and near infrared (NIR) photometry and spectroscopy of the type IIP supernova, SN 2004et. In combination with already published data, this provides one of the most complete studies of optical and NIR data for any type IIP SN from just after explosion to +500 days. The contribution of the NIR flux to the bolometric light curve is estimated to increase from 15% at explosion to around 50% at the end of the plateau and then declines to 40% at 300 days. SN 2004et is one of the most luminous IIP SNe which has been well studied, and with a luminosity of log L = 42.3 erg/s, it is 2 times brighter than SN 1999em. We provide parametrised bolometric corrections as a function of time for SN 2004et and three other IIP SNe that have extensive optical and NIR data, which can be used as templates for future events. We compare the physical parameters of SN 2004et with those of other IIP SNe and find kinetic energies spanning the range of 10^50-10^51 ergs. We compare the ejected masses calculated from hy...

  10. PUSHing Core-Collapse Supernovae to Explosions in Spherical Symmetry: Explodability and Nucleosynthesis Yields

    Science.gov (United States)

    Sinha, Sanjana; Ebinger, Kevin; Frohlich, Carla; Perego, Albino; Hempel, Matthias; Liebendoerfer, Matthias; Thielemann, F.-K.

    2017-01-01

    Core-collapse supernovae (CCSNe) are the highly energetic deaths of massive stars. They play a vital role in the synthesis and dissemination of many chemical elements. CCSN nucleosynthesis calculations have previously relied on artificial explosion methods that do not adequately capture the physics of the innermost stellar layers. Multidimensional simulations currently being performed to fully unravel the explosion mechanism of CCSNe are very computationally expensive. The PUSH method, calibrated against SN1987A, provides parametrized spherically symmetric models that follow the consistent evolution of the proto-neutron star as well as the electron fraction of the ejecta. This method is computationally affordable and captures the physics relevant for nucleosynthesis calculations. Here, we present the results of a broad study that investigates the explodability and nucleosynthesis yields of progenitors covering a wide range of ZAMS masses. Comparisons of the predicted explosion properties and yields with observational CCSNe and metal-poor star data will also be presented. The complete set of nucleosynthesis yields will be a valuable input to models of galactic chemical evolution. United States Department of Energy (DOE Grant No. SC0010263).

  11. A Missing-Link in the Supernova-GRB Connection: The Case of SN 2012ap

    CERN Document Server

    Chakraborti, Sayan; Chomiuk, Laura; Kamble, Atish; Yadav, Naveen; Ray, Alak; Hurley, Kevin; Margutti, Raffaella; Milisavljevic, Dan; Bietenholz, Michael; Brunthaler, Andreas; Pignata, Giuliano; Pian, Elena; Mazzali, Paolo; Fransson, Claes; Bartel, Norbert; Hamuy, Mario; Levesque, Emily; MacFadyen, Andrew; Dittmann, Jason; Krauss, Miriam; Briggs, M S; Connaughton, V; Yamaoka, K; Takahashi, T; Ohno, M; Fukazawa, Y; Tashiro, M; Terada, Y; Murakami, T; Goldsten, J; Barthelmy, S; Gehrels, N; Cummings, J; Krimm, H; Palmer, D; Golenetskii, S; Aptekar, R; Frederiks, D; Svinkin, D; Cline, T; Mitrofanov, I G; Golovin, D; Litvak, M L; Sanin, A B; Boynton, W; Fellows, C; Harshman, K; Enos, H; von Kienlin, A; Rau, A; Zhang, X; Savchenko, V

    2014-01-01

    Gamma Ray Bursts (GRBs) are characterized by ultra-relativistic outflows, while supernovae are generally characterized by non-relativistic ejecta. GRB afterglows decelerate rapidly usually within days, because their low-mass ejecta rapidly sweep up a comparatively larger mass of circumstellar material. However supernovae, with heavy ejecta, can be in nearly free expansion for centuries. Supernovae were thought to have non-relativistic outflows except for few relativistic ones accompanied by GRBs. This clear division was blurred by SN 2009bb, the first supernova with a relativistic outflow without an observed GRB. Yet the ejecta from SN 2009bb was baryon loaded, and in nearly-free expansion for a year, unlike GRBs. We report the first supernova discovered without a GRB, but with rapidly decelerating mildly relativistic ejecta, SN 2012ap. This shows that central engines in type Ic supernovae, even without an observed GRB, can produce both relativistic and rapidly decelerating outflows like GRBs.

  12. Chaos and Turbulent Nucleosynthesis Prior to a Supernova Explosion

    CERN Document Server

    Arnett, W David; Viallet, Maxime

    2013-01-01

    Three-dimensional (3D), time dependent numerical simulations, of flow of matter in stars, now have sufficient resolution to be fully turbulent. The late stages of the evolution of massive stars, leading up to core collapse to a neutron star (or black hole), and often to supernova explosion and nucleosynthesis, are strongly convective because of vigorous neutrino cooling and nuclear heating. Unlike models based on current stellar evolutionary practice, these simulations show a chaotic dynamics characteristic of highly turbulent flow. Theoretical analysis of this flow, both in the Reynolds-averaged Navier-Stokes (RANS) framework and by simple dynamic models, show an encouraging consistency with the numerical results. It may now be possible to develop physically realistic and robust procedures for convection and mixing which (unlike 3D numerical simulation) may be applied throughout the long life times of stars. In addition, a new picture of the presupernova stages is emerging which is more dynamic and interesti...

  13. Impacts of Collective Neutrino Oscillations on Supernova Explosions

    CERN Document Server

    Suwa, Yudai; Takiwaki, Tomoya; Liebendoerfer, Matthias; Sato, Katsuhiko

    2011-01-01

    By performing a series of one- and two-dimensional (1-, 2D) hydrodynamic simulations with spectral neutrino transport, we study possible impacts of collective neutrino oscillations on the dynamics of core-collapse supernovae. To model the spectral swapping which is one of the possible outcome of the collective neutrino oscillations, we parametrize the onset time when the spectral swap begins, the radius where the spectral swap occurs, and the threshold energy above which the spectral interchange between heavy-lepton neutrinos and electron/anti-electron neutrinos takes place, respectively. By doing so, we systematically study how the neutrino heating enhanced by the spectral swapping could affect the shock evolution as well as the matter ejection. We also investigate the progenitor dependence using a suite of progenitor models (13, 15, 20, and 25 $M_\\odot$). We find that there is a critical heating rate induced by the spectral swapping to trigger explosions, which significantly differs between the progenitors....

  14. The Spectral SN-GRB Connection: Systematic Spectral Comparisons between Type Ic Supernovae, broad-lined Type Ic Supernovae with and without Gamma-Ray Bursts

    CERN Document Server

    Modjaz, Maryam; Bianco, Federica B; Graur, Or

    2015-01-01

    We present the first systematic investigation of spectral properties of 17 Type Ic Supernovae (SNe Ic), 10 broad-lined SNe Ic (SNe Ic-bl) without observed Gamma-Ray Bursts (GRBs) and 10 SNe Ic-bl with GRBs (SN-GRBs) as a function of time in order to probe their explosion conditions and progenitors. We analyze a total of 396 spectra, which were drawn from published spectra of individual SNe as well as from the densely time-sampled spectra data of Modjaz et al. (2014). In order to quantify the diversity of the SN spectra as a function of SN subtype, we construct average spectra of SNe Ic, SNe Ic-bl without GRBs and SNe Ic-bl with GRBs, along with standard deviation and maximum deviation contours. We find that SN~1994I is not a typical SN Ic, in contrast to common belief, while the spectra of SN 1998bw/GRB 980425 are representative of mean spectra of SNe Ic-bl. We measure the ejecta absorption and width velocities (as traced by FeII 5169) and find that SNe Ic-bl with GRBs, on average, have quantifiably higher ab...

  15. The ASAS-SN Bright Supernova Catalog I: 2013-2014

    Science.gov (United States)

    Holoien, T. W.-S.; Stanek, K. Z.; Kochanek, C. S.; Shappee, B. J.; Prieto, J. L.; Brimacombe, J.; Bersier, D.; Bishop, D. W.; Dong, Subo; Brown, J. S.; Danilet, A. B.; Simonian, G. V.; Basu, U.; Beacom, J. F.; Falco, E.; Pojmanski, G.; Skowron, D. M.; Woźniak, P. R.; Ávila, C. G.; Conseil, E.; Contreras, C.; Cruz, I.; Fernández, J. M.; Koff, R. A.; Guo, Zhen; Herczeg, G. J.; Hissong, J.; Hsiao, E. Y.; Jose, J.; Kiyota, S.; Long, Feng; Monard, L. A. G.; Nicholls, B.; Nicolas, J.; Wiethoff, W. S.

    2016-09-01

    We present basic statistics for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during its first year-and-a-half of operations, spanning 2013 and 2014. We also present the same information for all other bright (mV ≤ 17), spectroscopically confirmed supernovae discovered from 2014 May 1 through the end of 2014, providing a comparison to the ASAS-SN sample starting from the point where ASAS-SN became operational in both hemispheres. In addition, we present collected redshifts and near-UV through IR magnitudes, where available, for all host galaxies of the bright supernovae in both samples. This work represents a comprehensive catalog of bright supernovae and their hosts from multiple professional and amateur sources, allowing for population studies that were not previously possible because the all-sky emphasis of ASAS-SN redresses many previously existing biases. In particular, ASAS-SN systematically finds bright supernovae closer to the centers of host galaxies than either other professional surveys or amateurs, a remarkable result given ASAS-SN's poorer angular resolution. This is the first of a series of yearly papers on bright supernovae and their hosts that will be released by the ASAS-SN team.

  16. The ASAS-SN bright supernova catalogue - I. 2013-2014

    Science.gov (United States)

    Holoien, T. W.-S.; Stanek, K. Z.; Kochanek, C. S.; Shappee, B. J.; Prieto, J. L.; Brimacombe, J.; Bersier, D.; Bishop, D. W.; Dong, Subo; Brown, J. S.; Danilet, A. B.; Simonian, G. V.; Basu, U.; Beacom, J. F.; Falco, E.; Pojmanski, G.; Skowron, D. M.; Woźniak, P. R.; Ávila, C. G.; Conseil, E.; Contreras, C.; Cruz, I.; Fernández, J. M.; Koff, R. A.; Guo, Zhen; Herczeg, G. J.; Hissong, J.; Hsiao, E. Y.; Jose, J.; Kiyota, S.; Long, Feng; Monard, L. A. G.; Nicholls, B.; Nicolas, J.; Wiethoff, W. S.

    2017-01-01

    We present basic statistics for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during its first year-and-a-half of operations, spanning 2013 and 2014. We also present the same information for all other bright (mV ≤ 17), spectroscopically confirmed supernovae discovered from 2014 May 1 through the end of 2014, providing a comparison to the ASAS-SN sample starting from the point where ASAS-SN became operational in both hemispheres. In addition, we present collected redshifts and near-UV through IR magnitudes, where available, for all host galaxies of the bright supernovae in both samples. This work represents a comprehensive catalogue of bright supernovae and their hosts from multiple professional and amateur sources, allowing for population studies that were not previously possible because the all-sky emphasis of ASAS-SN redresses many previously existing biases. In particular, ASAS-SN systematically finds bright supernovae closer to the centres of host galaxies than either other professional surveys or amateurs, a remarkable result given ASAS-SN's poorer angular resolution. This is the first of a series of yearly papers on bright supernovae and their hosts that will be released by the ASAS-SN team.

  17. Early Radio and X-Ray Observations of the Youngest Nearby Type Ia Supernova PTF 11kly (SN 2011fe)

    Science.gov (United States)

    Horesh, Assaf; Kulkarni, S. R.; Fox, Derek B.; Carpenter, John; Kasliwal, Mansi M.; Ofek, Eran O.; Quimby, Robert; Gal-Yam, Avishay; Cenko, S. Bradley; deBruyn, A. G.; Kamble, Atish; Wijers, Ralph A. M. J.; vanderHorst, Alexander J.; Kouveliotou, Chryssa; Podsiadlowski, Philipp; Sullivan, Mark; Maguire, Kate; Howell, D. Andrew; Nugent, Peter E.; Gehrels, Neil; Law, Nicolas M.; Poznanski, Dovi; Shara, Michael

    2012-01-01

    On August 24 (UT) the Palomar Transient Factory (PTF) discovered PTF11kly (SN 2011fe), the youngest and most nearby type Ia supernova (SN Ia) in decades. We followed this event up in the radio (centimeter and millimeter bands) and X-ray bands, starting about a day after the estimated explosion time. We present our analysis of the radio and X-ray observations, yielding the tightest constraints yet placed on the pre-explosion mass-loss rate from the progenitor system of this supernova. We find a robust limit of M(raised dot) less than or equal to 10(exp -8) (w /100 kilometers per second ) solar mass yr(exp -1) from sensitive X-ray non-detections, as well as a similar limit from radio data, which depends, however, on assumptions about microphysical parameters. We discuss our results in the context of single-degenerate models for SNe Ia and find that our observations modestly disfavor symbiotic progenitor models involving a red giant donor, but cannot constrain systems accreting from main sequence or sub-giant stars, including the popular supersoft channel. In view of the proximity of PTF11kly and the sensitivity of our prompt observations we would have to wait for a long time (decade or longer) in order to more meaningfully probe the circumstellar matter of Ia supernovae.

  18. A New Multi-Dimensional General Relativistic Neutrino Hydrodynamics Code of Core-Collapse Supernovae III. Gravitational Wave Signals from Supernova Explosion Models

    CERN Document Server

    Mueller, Bernhard; Marek, Andreas

    2012-01-01

    We present a detailed theoretical analysis of the gravitational-wave (GW) signal of the post-bounce evolution of core-collapse supernovae (SNe), employing for the first time relativistic, two-dimensional (2D) explosion models with multi-group, three-flavor neutrino transport based on the ray-by-ray-plus approximation. The waveforms reflect the accelerated mass motions associated with the characteristic evolutionary stages that were also identified in previous works: A quasi-periodic modulation by prompt postshock convection is followed by a phase of relative quiescence before growing amplitudes signal violent hydrodynamical activity due to convection and the standing accretion shock instability during the accretion period of the stalled shock. Finally, a high-frequency, low-amplitude variation from proto-neutron star (PNS) convection below the neutrinosphere appears superimposed on the low-frequency trend associated with the aspherical expansion of the SN shock after the onset of the explosion. Relativistic e...

  19. SN 2013ab : A normal type IIP supernova in NGC 5669

    CERN Document Server

    Bose, Subhash; Misra, Kuntal; Pumo, Maria Letizia; Zampieri, Luca; Sand, David; Kumar, Brijesh; Pastorello, Andrea; Sutaria, Firoza; Maccarone, Thomas J; Kumar, Brajesh; Graham, M L; Howell, D Andy; Ochner, Paolo; Chandola, H C; Pandey, Shashi B

    2015-01-01

    We present densely-sampled ultraviolet/optical photometric and low-resolution optical spectroscopic observations of the type IIP supernova 2013ab in the nearby ($\\sim$24 Mpc) galaxy NGC 5669, from 2 to 190d after explosion. Continuous photometric observations, with the cadence of typically a day to one week, were acquired with the 1-2m class telescopes in the LCOGT network, ARIES telescopes in India and various other telescopes around the globe. The light curve and spectra suggest that the SN is a normal type IIP event with a plateau duration of $ \\sim80 $ days with mid plateau absolute visual magnitude of -16.7, although with a steeper decline during the plateau (0.92 mag 100 d$ ^{-1} $ in $ V $ band) relative to other archetypal SNe of similar brightness. The velocity profile of SN 2013ab shows striking resemblance with those of SNe 1999em and 2012aw. Following the Rabinak & Waxman (2011) prescription, the initial temperature evolution of the SN emission allows us to estimate the progenitor radius to be...

  20. Detection of an outburst one year prior to the explosion of SN 2011ht

    CERN Document Server

    Fraser, M; Kotak, R; Smartt, S J; Smith, K W; Polshaw, J; Drake, A J; Boles, T; Lee, C -H; Burgett, W S; Chambers, K C; Draper, P W; Flewelling, H; Hodapp, K W; Kaiser, N; Kudritzki, R -P; Magnier, E A; Price, P A; Tonry, J L; Wainscoat, R J; Waters, C

    2013-01-01

    Using imaging from the Pan-STARRS1 survey, we identify a precursor outburst at epochs 287 and 170 days prior to the reported explosion of the purported Type IIn supernova (SN) 2011ht. In the Pan-STARRS data, a source coincident with SN 2011ht is detected exclusively in the \\zps\\ and \\yps-bands. An absolute magnitude of M$_z\\simeq$-11.8 suggests that this was an outburst of the progenitor star. Unfiltered, archival Catalina Real Time Transient survey images also reveal a coincident source from at least 258 to 138 days before the main event. We suggest that the outburst is likely to be an intrinsically red eruption, although we cannot conclusively exclude a series of erratic outbursts which were observed only in the redder bands by chance. This is only the fourth detection of an outburst prior to a claimed SN, and lends credence to the possibility that many more interacting transients have pre-explosion outbursts, which have been missed by current surveys.

  1. DETECTION OF AN OUTBURST ONE YEAR PRIOR TO THE EXPLOSION OF SN 2011ht

    Energy Technology Data Exchange (ETDEWEB)

    Fraser, M.; Magee, M.; Kotak, R.; Smartt, S. J.; Smith, K. W.; Polshaw, J. [School of Mathematics and Physics, Queens University Belfast, Belfast BT7 1NN (United Kingdom); Drake, A. J. [Department of Astronomy and the Center for Advanced Computing Research, California Institute of Technology, Pasadena, CA 91225 (United States); Boles, T. [Coddenham Astronomical Observatory, Suffolk IP6 9QY (United Kingdom); Lee, C.-H. [University Observatory Munich, Scheinerstrasse 1, D-81679 Munich (Germany); Burgett, W. S.; Chambers, K. C.; Flewelling, H.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Tonry, J. L.; Wainscoat, R. J. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Draper, P. W. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Price, P. A., E-mail: m.fraser@qub.ac.uk [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); and others

    2013-12-10

    Using imaging from the Pan-STARRS1 survey, we identify a precursor outburst at 287 and 170 days prior to the reported explosion of the purported Type IIn supernova (SN) 2011ht. In the Pan-STARRS data, a source coincident with SN 2011ht is detected exclusively in the z {sub P1} and y {sub P1}-bands. An absolute magnitude of M{sub z} ≅ –11.8 suggests that this was an outburst of the progenitor star. Unfiltered, archival Catalina Real Time Transient Survey images also reveal a coincident source from at least 258 to 138 days before the main event. We suggest that the outburst is likely to be an intrinsically red eruption, although we cannot conclusively exclude a series of erratic outbursts which were observed only in the redder bands by chance. This is only the fourth detection of an outburst prior to a claimed SN, and lends credence to the possibility that many more interacting transients have pre-explosion outbursts, which have been missed by current surveys.

  2. SN 2010ay is a Luminous and Broad-lined Type Ic Supernova within a Low-metallicity Host Galaxy

    CERN Document Server

    Sanders, Nathan E; Valenti, S; Chomiuk, L; Berger, E; Smartt, S; Hurley, K; Barthelmy, S D; Chornock, R; Foley, R J; Levesque, E M; Narayan, G; Kirshner, R P; Botticella, M T; Briggs, M S; Connaughton, V; Terada, Y; Gehrels, N; Golenetskii, S; Mazets, E; Cline, T; von Kienlin, A; Boynton, W; Chambers, K C; Grav, T; Heasley, J N; Hodapp, K W; Jedicke, R; Kaiser, N; Kudritzki, R -P; Luppino, G A; Lupton, R H; Magnier, E A; Monet, D G; Morgan, J S; Onaka, P M; Price, P A; Stubbs, C W; Tonry, J L; Wainscoat, R J; Waterson, M F

    2011-01-01

    [abridged] We report on our serendipitous pre-discovery detection and detailed follow-up of the broad-lined Type Ic supernova SN 2010ay at z\\approx0.067 imaged by the Pan-STARRS1 3{\\pi} survey just \\sim3 days after explosion. We estimate the explosion date and the peak luminosity of the SN, MR\\approx-20.2 mag, significantly brighter than known GRB-SNe and one of the most luminous SNe Ic ever discovered. We measure the photospheric expansion velocity of the explosion, v_ph\\approx19.2x10^3 km/s at \\sim40 days after explosion. In comparison with other broad-lined SNe, the characteristic velocity of SN 2010ay is 2-5x higher and similar to the measurements for GRB-SNe at comparable epochs. Moreover the velocity declines two times slower than other SNe Ic-BL and GRB-SNe. Assuming that the optical emission is powered by radioactive decay, the peak magnitude implies the synthesis of an unusually large mass of 56 Ni, M_Ni=0.9+0.2 M_solar. Our modeling of the light-curve points to a total ejecta mass, Mej\\approx4.7M_so...

  3. SN 2006oz: rise of a super-luminous supernova observed by the SDSS-II SN Survey

    DEFF Research Database (Denmark)

    Leloudas, Georgios; Chatzopoulos, E.; Dilday, B.;

    2012-01-01

    to contribute to a better understanding of these objects by studying SN 2006oz, a newly-recognized member of this class. Methods. We present multi-color light curves of SN 2006oz from the SDSS-II SN Survey that cover its rise time, as well as an optical spectrum that shows that the explosion occurred at z ~ 0...

  4. The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode As Deflagrations?

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M.M.; Li, W.; Frieman, J.A.; Blinnikov, S.I.; DePoy, D.; Prieto, J.L.; Milne, P.; Contreras, C.; Folatelli, Gaston; Morrell, N.; Hamuy, M.; Suntzeff, N.B.; Roth, M.; Gonzalez, S.; Krzeminski, W.; Filippenko, A.V.; Freedman, W.L.; Chornock, R.; Jha, S.; Madore, B.F.; Persson, S.E.; /Las Campanas Observ. /UC, Berkeley, Astron. Dept.

    2006-11-14

    We present extensive u{prime}g{prime}r{prime}i{prime} BV RIY JHK{sub s} photometry and optical spectroscopy of SN 2005hk. These data reveal that SN 2005hk was nearly identical in its observed properties to SN 2002cx, which has been called 'the most peculiar known type Ia supernova'. Both supernovae exhibited high ionization SN 1991T-like pre-maximum spectra, yet low peak luminosities like SN 1991bg. The spectra reveal that SN 2005hk, like SN 2002cx, exhibited expansion velocities that were roughly half those of typical type Ia supernovae. The R and I light curves of both supernovae were also peculiar in not displaying the secondary maximum observed for normal type Ia supernovae. Our Y JH photometry of SN 2005hk reveals the same peculiarity in the near-infrared. By combining our optical and near-infrared photometry of SN 2005hk with published ultraviolet light curves obtained with the Swift satellite, we are able to construct a bolometric light curve from {approx} 10 days before to {approx}60 days after B maximum. The shape and unusually low peak luminosity of this light curve, plus the low expansion velocities and absence of a secondary maximum at red and near-infrared wavelengths, are all in reasonable agreement with model calculations of a 3D deflagration which produces {approx} 0.25 M{sub {circle_dot}} of {sup 56}Ni.

  5. Pre-explosive observational properties of Type Ia supernovae

    Science.gov (United States)

    Tornambé, A.; Piersanti, L.

    2013-05-01

    several million years) to attain the explosion after the above mentioned conditions cease to keep stable the WD. Therefore, it is practically impossible to detect the trace of the exploding WD companion in recent pre-explosion frames of even very near Type Ia supernova events.

  6. SN 2000cx and SN 2013bh: Extremely Rare, Nearly Twin Type Ia Supernovae

    CERN Document Server

    Silverman, Jeffrey M; Kasliwal, Mansi M; Fox, Ori D; Cao, Yi; Johansson, Joel; Perley, Daniel A; Tal, David; Wheeler, J Craig; Amanullah, Rahman; Arcavi, Iair; Bloom, Joshua S; Gal-Yam, Avishay; Goobar, Ariel; Kulkarni, Shrinivas R; Laher, Russ; Lee, William H; Marion, G H; Nugent, Peter E; Shivvers, Isaac

    2013-01-01

    The Type Ia supernova (SN Ia) SN 2000cx was one of the most peculiar transients ever discovered. While its rise to maximum brightness was typical for a SN Ia, its decline was slower, causing standard light curve fitting algorithms to fail; its spectra indicated a high photospheric temperature. Thirteen years later SN 2013bh (aka iPTF13abc), the first near identical twin of SN 2000cx, was discovered. We obtained optical and near-IR photometry and low-resolution optical spectroscopy of this object from discovery until about 1 month past r-band maximum brightness. The spectra of both objects indicate the presence of iron-group elements (Co II, Ni II, Fe II, Fe III, and high-velocity features [HVFs] of Ti II), intermediate-mass elements (Si II, Si III, and S II), in addition to separate normal velocity features (~12000 km/s) and HVFs (~24000 km/s) of Ca II. Persistent absorption from Fe III and Si III, along with the colour evolution, imply relatively high blackbody temperatures for SNe 2013bh and 2000cx (~12000 ...

  7. Supernova SN 1006 in two historic Yemeni reports

    CERN Document Server

    Rada, Wafiq

    2015-01-01

    We present two Arabic texts of historic observations of supernova SN 1006 from Yemen as reported by al-Yamani and Ibn al-Dayba (14th to 16th century AD). An English translation of the report by the latter was given before (Stephenson & Green 2002), but the original Arabic text was not yet published. In addition, we present for the first time the earlier report, also from Yemen, namely by al-Yamani in its original Arabic and with our English translation. It is quite obvious that the report by Ibn al-Dayba is based on the report by al-Yamani (or a common source), but the earlier report by al-Yamani is more detailed and in better (Arabic) language. We discuss in detail the dating of these observations. The most striking difference to other reports about SN 1006 is the apparent early discovery in Yemen in the evening of 15th of Rajab of the year 396h (i.e. AD 1006 Apr 17 \\pm 2 on the Julian calendar), as reported by both al-Yamani and Ibn al-Dayba. i.e. about 1.5 weeks earlier than the otherwise earliest know...

  8. SN2002es-like Supernovae From Different Viewing Angles

    CERN Document Server

    Cao, Yi; Gal-Yam, Avishay; Papadogiannakis, S; Nugent, P E; Masci, Frank J; Bue, Brian D

    2016-01-01

    In this letter, we compare optical light curves of two SN2002es-like Type Ia supernovae, iPTF14atg and iPTF14dpk, from the intermediate Palomar Transient Factory. Although the two light curves resemble each other around and after maximum, they show distinct early-phase rise behavior in the $\\textit{r}$-band. On the one hand, iPTF14atg revealed a slow and steady rise which lasted for 22 days with a mean rise rate of $0.2\\sim0.3\\,\\textrm{mag}\\,\\textrm{day}^{-1}$, before it reached the $R$-band peak ($-18.05\\,$mag). On the other hand, iPTF14dpk rose rapidly to $-17\\,$mag within a day of discovery with a rise rate $>1.8\\,\\textrm{mag}\\,\\textrm{day}^{-1}$, and then rose slowly to its peak ($-18.19\\,$mag) with a rise rate similar to iPTF14atg. The apparent total rise time of iPTF14dpk is therefore only 16 days. We show that emission from iPTF14atg before $-17\\,$days with respect to its maximum can be entirely attributed to radiation produced by collision between the SN and its companion star. Such emission is absent...

  9. SN 2010ay Is a Luminous and Broad-Lined Type Ic Supernova Within a Low-Metallicity Host Galaxy

    Science.gov (United States)

    Sanders, N. E.; Soderberg, A. M.; Valenti, S.; Foley, R. J.; Chornock, R.; Chomiuk, L.; Berger, E.; Smartt, S.; Hurley, K.; Barthelmy, S. D.; Levesque, E. M.; Narayan, G.; Botticella, M. T.; Briggs, M. S.; Connaughton, V.; Terada, Y.; Gehrels, N.; Golenetskii, S.; Mazets, E.; Cline, T.; von Kienlin, A.; Boynton, W.; Chambers, K. C.; Grav, T.; Heasley, J. N.

    2012-01-01

    We report on our serendipitous pre-discovery detection and follow-up observations of the broad-lined Type Ic supernova (SN Ic) 2010ay at z = 0.067 imaged by the Pan-STARRS1 3pi survey just approximately 4 days after explosion. The supernova (SN) had a peak luminosity, MR approx. -20.2 mag, significantly more luminous than known GRB-SNe and one of the most luminous SNe Ib/c ever discovered. The absorption velocity of SN 2010ay is v Si (is) approx. 19×10(exp 3) km s-1 at approximately 40 days after explosion, 2-5 times higher than other broad-lined SNe and similar to the GRB-SN 2010bh at comparable epochs. Moreover, the velocity declines approximately 2 times slower than other SNe Ic-BL and GRB-SNe. Assuming that the optical emission is powered by radioactive decay, the peak magnitude implies the synthesis of an unusually large mass of 56Ni, MNi = 0.9 solar mass. Applying scaling relations to the light curve, we estimate a total ejecta mass, Mej (is) approx. 4.7 solar mass, and total kinetic energy, EK (is) approx. 11 × 10(exp 51) erg. The ratio of MNi to Mej is approximately 2 times as large for SN 2010ay as typical GRB-SNe and may suggest an additional energy reservoir. The metallicity (log(O/H)PP04 + 12 = 8.19) of the explosion site within the host galaxy places SN 2010ay in the low-metallicity regime populated by GRB-SNe, and (is) approximately 0.5(0.2) dex lower than that typically measured for the host environments of normal (broad-lined) SNe Ic. We constrain any gamma-ray emission with E(gamma) (is) approximately less than 6 × 10(exp 48) erg (25-150 keV), and our deep radio follow-up observations with the Expanded Very Large Array rule out relativistic ejecta with energy E (is) approximately greater than 10(exp 48) erg. We therefore rule out the association of a relativistic outflow like those that accompanied SN 1998bw and traditional long-duration gamma-ray bursts (GRBs), but we place less-stringent constraints on a weak afterglow like that seen from XRF

  10. Type IIb supernova SN 2011dh: Spectra and photometry from the ultraviolet to the near-infrared

    Energy Technology Data Exchange (ETDEWEB)

    Marion, G. H.; Kirshner, Robert P.; Foley, Ryan J.; Berlind, Perry; Bieryla, Allyson; Calkins, Michael L.; Challis, Peter; Chornock, Ryan; Esquerdo, Gilbert A.; Falco, Emilio E.; Friedman, Andrew S. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Vinko, Jozsef [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Bloom, Joshua S. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Chevalier, Roger A. [Astronomy Department, University of Virginia, Charlottesville, VA 22904 (United States); Culliton, Chris; Curtis, Jason L. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Everett, Mark E. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); France, Kevin [Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Fransson, Claes [Department of Astronomy, The Oskar Klein Centre, Stockholm University, S-106 91 Stockholm (Sweden); Garnavich, Peter, E-mail: gmarion@cfa.harvard.edu [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); and others

    2014-02-01

    We report spectroscopic and photometric observations of the Type IIb SN 2011dh obtained between 4 and 34 days after the estimated date of explosion (May 31.5 UT). The data cover a wide wavelength range from 2000 Å in the ultraviolet (UV) to 2.4 μm in the near-infrared (NIR). Optical spectra provide line profiles and velocity measurements of H I, He I, Ca II, and Fe II that trace the composition and kinematics of the supernova (SN). NIR spectra show that helium is present in the atmosphere as early as 11 days after the explosion. A UV spectrum obtained with the Space Telescope Imaging Spectrograph reveals that the UV flux for SN 2011dh is low compared to other SN IIb. Modeling the spectrum with SYNOW suggests that the UV deficit is due to line blanketing from Ti II and Co II. The H I and He I velocities in SN 2011dh are separated by about 4000 km s{sup –1} at all phases. A velocity gap is consistent with models for a preexplosion structure in which a hydrogen-rich shell surrounds the progenitor. We estimate that the H shell of SN 2011dh is ≈8 times less massive than the shell of SN 1993J and ≈3 times more massive than the shell of SN 2008ax. Light curves (LCs) for 12 passbands are presented: UVW2, UVM2, UVW1, U, u', B, V, r', i', J, H, and K{sub s} . In the B band, SN 2011dh reached peak brightness of 13.17 mag at 20.0 ± 0.5 after the explosion. The maximum bolometric luminosity of 1.8 ± 0.2 × 10{sup 42} erg s{sup –1} occurred ≈22 days after the explosion. NIR emission provides more than 30% of the total bolometric flux at the beginning of our observations, and the NIR contribution increases to nearly 50% of the total by day 34. The UV produces 16% of the total flux on day 4, 5% on day 9, and 1% on day 34. We compare the bolometric LCs of SN 2011dh, SN 2008ax, and SN 1993J. The LC are very different for the first 12 days after the explosions, but all three SN IIb display similar peak luminosities, times of peak, decline rates, and

  11. Explosion Dynamics of Parametrized Spherically Symmetric Core-Collapse Supernova Simulations

    CERN Document Server

    Ebinger, Kevin; Fröhlich, Carla; Perego, Albino; Hempel, Matthias; Eichler, Marius; Casanova, Jordi; Liebendörfer, Matthias; Thielemann, Friedrich-Karl

    2016-01-01

    We report on a method, PUSH, for triggering core-collapse supernova (CCSN) explosions of massive stars in spherical symmetry. This method provides a framework to study many important aspects of core collapse supernovae: the effects of the shock passage through the star, explosive supernova nucleosynthesis and the progenitor-remnant connection. Here we give an overview of the method, compare the results to multi-dimensional simulations and investigate the effects of the progenitor and the equation of state on black hole formation.

  12. Abundance stratification in Type Ia supernovae - V. SN 1986G bridging the gap between normal and subluminous SNe Ia

    CERN Document Server

    Ashall, C; Pian, E; James, P A

    2016-01-01

    A detailed spectroscopic analysis of SN 1986G has been performed. SN 1986G `bridges the gap' between normal and sub luminous type Ia supernova (SNe Ia). The abundance tomography technique is used to determine the abundance distribution of the elements in the ejecta. SN 1986G was found to be a low energy Chandrasekhar mass explosion. Its kinetic energy was 70% of the standard W7 model (0.9x10$^{51}$erg). Oxygen dominates the ejecta from the outermost layers down to $\\sim$9000kms$^{-1}$ , intermediate mass elements (IME) dominate from $\\sim$ 9000kms$^{-1}$ to $\\sim$ 3500kms$^{-1}$ with Ni and Fe dominating the inner layers $<\\sim$ 3500kms$^{-1}$. The final masses of the main elements in the ejecta were found to be, O=0.33M, IME=0.69M, stable NSE=0.21M, $^{56}$Ni=0.14M. An upper limit of the carbon mass is set at C=0.02M. The spectra of SN1986G consist of almost exclusively singly ionised species. SN1986G can be thought of as a low luminosity extension of the main population of SN Ia, with a large deflagratio...

  13. Type Ia Supernova Rate Measurements to Redshift 2.5 from Candles: Searching for Prompt Explosions in the Early Universe

    Science.gov (United States)

    Rodney, Steven A.; Riess, Adam G.; Strogler, Louis-Gregory; Dahlen, Tomas; Graur, Or; Casertano, Stefano; Dickinson, Mark E.; Ferguson, Henry C.; Garnavich, Peter; Cenko, Stephen Bradley

    2014-01-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) was a multi-cycle treasury program on the Hubble Space Telescope(HST) that surveyed a total area of approx. 0.25 deg(sup 2) with approx.900 HST orbits spread across five fields over three years. Within these survey images we discovered 65 supernovae (SNe) of all types, out to z approx. 2.5. We classify approx. 24 of these as Type Ia SNe (SNe Ia) based on host galaxy redshifts and SN photometry (supplemented by grism spectroscopy of six SNe). Here we present a measurement of the volumetric SN Ia rate as a function of redshift, reaching for the first time beyond z = 2 and putting new constraints on SN Ia progenitor models. Our highest redshift bin includes detections of SNe that exploded when the universe was only approx. 3 Gyr old and near the peak of the cosmic star formation history. This gives the CANDELS high redshift sample unique leverage for evaluating the fraction of SNe Ia that explode promptly after formation (500 Myr). Combining the CANDELS rates with all available SN Ia rate measurements in the literature we find that this prompt SN Ia fraction isfP0.530.09stat0.100.10sys0.26, consistent with a delay time distribution that follows a simplet1power law for all timest40 Myr. However, mild tension is apparent between ground-based low-z surveys and space-based high-z surveys. In both CANDELS and the sister HST program CLASH (Cluster Lensing And Supernova Survey with Hubble), we find a low rate of SNe Ia at z > 1. This could be a hint that prompt progenitors are in fact relatively rare, accounting for only 20 of all SN Ia explosions though further analysis and larger samples will be needed to examine that suggestion.

  14. Type Iax Supernovae: A New Class of Stellar Explosion

    CERN Document Server

    Foley, Ryan J; Chornock, R; Ganeshalingam, M; Li, W; Marion, G H; Morrell, N I; Pignata, G; Stritzinger, M D; Silverman, J M; Wang, X; Anderson, J P; Filippenko, A V; Freedman, W L; Hamuy, M; Jha, S W; Kirshner, R P; McCully, C; Persson, S E; Phillips, M M; Reichart, D E; Soderberg, A M

    2012-01-01

    We describe observed properties of the Type Iax class of supernovae (SNe Iax), consisting of SNe observationally similar to its prototypical member, SN 2002cx. The class currently has 25 members, and we present optical photometry and/or optical spectroscopy for most of them. SNe Iax are spectroscopically similar to SNe Ia, but have lower maximum-light velocities (2000 M_V,peak > -18.9 mag), and most have hot photospheres. Relative to SNe Ia, SNe Iax have low luminosities for their light-curve shape. There is a correlation between luminosity and light-curve shape, similar to that of SNe Ia, but offset from that of SNe Ia and with larger scatter. Despite a host-galaxy morphology distribution that is highly skewed to late-type galaxies without any SNe Iax discovered in elliptical galaxies, there are several indications that the progenitor stars are white dwarfs (WDs): evidence of C/O burning in their maximum-light spectra, low ejecta masses, strong Fe lines in their late-time spectra, a lack of X-ray detections...

  15. Chaos and turbulent nucleosynthesis prior to a supernova explosion

    Directory of Open Access Journals (Sweden)

    W. D. Arnett

    2014-03-01

    Full Text Available Three-dimensional (3D, time dependent numerical simulations of flow of matter in stars, now have sufficient resolution to be fully turbulent. The late stages of the evolution of massive stars, leading up to core collapse to a neutron star (or black hole, and often to supernova explosion and nucleosynthesis, are strongly convective because of vigorous neutrino cooling and nuclear heating. Unlike models based on current stellar evolutionary practice, these simulations show a chaotic dynamics characteristic of highly turbulent flow. Theoretical analysis of this flow, both in the Reynolds-averaged Navier-Stokes (RANS framework and by simple dynamic models, show an encouraging consistency with the numerical results. It may now be possible to develop physically realistic and robust procedures for convection and mixing which (unlike 3D numerical simulation may be applied throughout the long life times of stars. In addition, a new picture of the presupernova stages is emerging which is more dynamic and interesting (i.e., predictive of new and newly observed phenomena than our previous one.

  16. Type Ia Supernovae and their Environment: Theory and Applications to SN 2014J

    CERN Document Server

    Dragulin, Paul

    2015-01-01

    We present theoretical semi-analytic models for the interaction of stellar winds with the interstellar medium (ISM) or prior mass loss implemented in our code SPICE (Supernovae Progenitor Interaction Calculator for parameterized Environments, available on request), assuming spherical symmetry and power-law ambient density profiles and using the Pi-theorem. This allows us to test a wide variety of configurations, their functional dependencies, and to find classes of solutions for given observations. Here, we study Type Ia (SN~Ia) surroundings of single and double degenerate systems, and their observational signatures. Winds may originate from the progenitor prior to the white dwarf (WD) stage, the WD, a donor star, or an accretion disk (AD). For M_Ch explosions,the AD wind dominates and produces a low-density void several light years across surrounded by a dense shell. The bubble explains the lack of observed interaction in late time SN light curves for, at least, several years. The shell produces narrow ISM l...

  17. Abundance stratification in Type Ia Supernovae - II: The rapidly declining, spectroscopically normal SN 2004eo

    CERN Document Server

    Mazzali, P A; Pastorello, A; Benetti, S; Hillebrandt, W

    2008-01-01

    The variation of properties of Type Ia supernovae, the thermonuclear explosions of Chandrasekhar-mass carbon-oxygen white dwarfs, is caused by different nucleosynthetic outcomes of these explosions, which can be traced from the distribution of abundances in the ejecta. The composition stratification of the spectroscopically normal but rapidly declining SN2004eo is studied performing spectrum synthesis of a time-series of spectra obtained before and after maximum, and of one nebular spectrum obtained about eight months later. Early-time spectra indicate that the outer ejecta are dominated by oxygen and silicon, and contain other intermediate-mass elements (IME), implying that the outer part of the star was subject only to partial burning. In the inner part, nuclear statistical equilibrium (NSE) material dominates, but the production of 56Ni was limited to ~0.43 \\pm 0.05 Msun. An innermost zone containing ~0.25 Msun of stable Fe-group material is also present. The relatively small amount of NSE material synthes...

  18. Exclusion of a luminous red giant as a companion star to the progenitor of supernova SN 2011fe.

    Science.gov (United States)

    Li, Weidong; Bloom, Joshua S; Podsiadlowski, Philipp; Miller, Adam A; Cenko, S Bradley; Jha, Saurabh W; Sullivan, Mark; Howell, D Andrew; Nugent, Peter E; Butler, Nathaniel R; Ofek, Eran O; Kasliwal, Mansi M; Richards, Joseph W; Stockton, Alan; Shih, Hsin-Yi; Bildsten, Lars; Shara, Michael M; Bibby, Joanne; Filippenko, Alexei V; Ganeshalingam, Mohan; Silverman, Jeffrey M; Kulkarni, S R; Law, Nicholas M; Poznanski, Dovi; Quimby, Robert M; McCully, Curtis; Patel, Brandon; Maguire, Kate; Shen, Ken J

    2011-12-14

    Type Ia supernovae are thought to result from a thermonuclear explosion of an accreting white dwarf in a binary system, but little is known of the precise nature of the companion star and the physical properties of the progenitor system. There are two classes of models: double-degenerate (involving two white dwarfs in a close binary system) and single-degenerate models. In the latter, the primary white dwarf accretes material from a secondary companion until conditions are such that carbon ignites, at a mass of 1.38 times the mass of the Sun. The type Ia supernova SN 2011fe was recently detected in a nearby galaxy. Here we report an analysis of archival images of the location of SN 2011fe. The luminosity of the progenitor system (especially the companion star) is 10-100 times fainter than previous limits on other type Ia supernova progenitor systems, allowing us to rule out luminous red giants and almost all helium stars as the mass-donating companion to the exploding white dwarf.

  19. Early radio and X-ray observations of the youngest nearby type Ia supernova PTF11kly (SN 2011fe)

    CERN Document Server

    Horesh, Assaf; Fox, Derek B; Carpenter, John; Kasliwal, Mansi M; Ofek, Eran O; Quimby, Robert; Gal-Yam, Avishay; Cenko, S Bradley; de Bruyn, A G; Kamble, Atish; Wijers, Ralph A M J; van der Horst, Alexander J; Kouveliotou, Chryssa; Podsiadlowski, Philipp; Sullivan, Mark; Maguire, Kate; Nugent, Peter E; Gehrels, Neil; Law, Nicholas M; Poznanski, Dovi; Shara, Michael

    2011-01-01

    On August 24 (UT) the Palomar Transient Factory (PTF) discovered PTF11kly (SN 2011fe), the youngest and most nearby type Ia supernova (SN Ia) in decades. We followed this event up in the radio (centimeter and millimeter bands) and X-ray bands, starting about a day after the estimated explosion time. We present our analysis of the radio and X-ray observations, yielding the tightest constraints yet placed on the pre-explosion mass-loss rate from the progenitor system of this supernova. We find a robust limit of dM/dt<10^-8 (w/100 km/s) [M_solar/yr] from sensitive X-ray non-detections, as well as a similar limit from radio data, which depends, however, on assumptions about microphysical parameters. We discuss our results in the context of single-degenerate models for SNe Ia and find that our observations modestly disfavor symbiotic progenitor models involving a red giant donor, but cannot constrain systems accreting from main-sequence or sub-giant stars, including the popular supersoft channel. In view of the...

  20. Type IIP Supernova SN 2004et: A Multi-Wavelength Study in X-Ray, Optical and Radio

    CERN Document Server

    Misra, Kuntal; Chandra, Poonam; Bhattacharya, D; Ray, Alak K; Sagar, Ram; Lewin, Walter H G

    2007-01-01

    We present X-ray, broad band optical and low frequency radio observations of the bright type IIP supernova SN 2004et. The \\cxo observed the supernova at three epochs, and the optical coverage spans a period of $\\sim$ 470 days since explosion. The X-ray emission softens with time, and we characterise the X-ray luminosity evolution as $\\Lx \\propto t^{-0.4}$. We use the observed X-ray luminosity to estimate a mass-loss rate for the progenitor star of $\\sim \\ee{2}{-6} M_\\odot \\mathrm{yr}^{-1}$. The optical light curve shows a pronounced plateau lasting for about 110 days. Temporal evolution of photospheric radius and color temperature during the plateau phase is determined by making black body fits. We estimate the ejected mass of $^{56}$Ni to be 0.06 $\\pm$ 0.03 M$_\\odot$. Using the expressions of Litvinova & Nad\\"{e}zhin (1985) we estimate an explosion energy of (0.98 $\\pm$ 0.25) $\\times 10^{51}$ erg. We also present a single epoch radio observation of SN 2004et. We compare this with the predictions of the m...

  1. 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

  2. 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

  3. The ASAS-SN Bright Supernova Catalog I: 2013-2014

    CERN Document Server

    Holoien, T W -S; Kochanek, C S; Shappee, B J; Prieto, J L; Brimacombe, J; Bersier, D; Bishop, D W; Dong, Subo; Brown, J S; Danilet, A B; Simonian, G V; Basu, U; Beacom, J F; Falco, E; Pojmanski, G; Skowron, D M; Wozniak, P R; Avila, C G; Conseil, E; Contreras, C; Cruz, I; Fernandez, J M; Koff, R A; Guo, Zhen; Herczeg, G J; Hissong, J; Hsiao, E Y; Jose, J; Kiyota, S; Long, Feng; Monard, L A G; Nicholls, B; Nicolas, J; Wiethoff, W S

    2016-01-01

    We present basic statistics for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during its first year-and-a-half of operations, spanning 2013 and 2014. We also present the same information for all other bright ($m_V\\leq17$), spectroscopically confirmed supernovae discovered from 2014 May 1 through the end of 2014, providing a comparison to the ASAS-SN sample starting from the point where ASAS-SN became operational in both hemispheres. In addition, we present collected redshifts and near-UV through IR magnitudes, where available, for all host galaxies of the bright supernovae in both samples. This work represents a comprehensive catalog of bright supernovae and their hosts from multiple professional and amateur sources, allowing for population studies that were not previously possible because the all-sky emphasis of ASAS-SN redresses most previously existing biases. In particular, ASAS-SN systematically finds supernovae closer to the centers of host galaxies than either other...

  4. VLBI observations of SN2011dh: imaging of the youngest radio supernova

    CERN Document Server

    Marti-Vidal, I; Paragi, Z; Yang, J; Marcaide, J M; Guirado, J C; Ros, E; Alberdi, A; Perez-Torres, M A; Argo, M K; van der Horst, A J; Garrett, M A; Stockdale, C J; Weiler, K W

    2011-01-01

    We report on the VLBI detection of supernova SN2011dh at 22GHz using a subset of the EVN array. The observations took place 14 days after the discovery of the supernova, thus resulting in a VLBI image of the youngest radio-loud supernova ever. We provide revised coordinates for the supernova with milli-arcsecond precision, linked to the ICRF. The recovered flux density is a factor 2 below the EVLA flux density reported by other authors at the same frequency and epoch of our observations. This discrepancy could be due to extended emission detected with the EVLA or to calibration problems in the VLBI and/or EVLA observations.

  5. Comprehensive Observations of the Bright and Energetic Type Iax SN 2012Z: Interpretation as a Chandrasekhar Mass White Dwarf Explosion

    CERN Document Server

    Stritzinger, M D; Hoeflich, P; Baron, E; Phillips, M M; Taddia, F; Foley, R J; Hsiao, E Y; Jha, S W; McCully, C; Pandya, V; Simon, J D; Benetti, S; Brown, P J; Burns, C R; Campillay, A; Contreras, C; Forster, F; Holmbo, S; Marion, G H; Morrell, N; Pignata, G

    2014-01-01

    We present UV through NIR broad-band photometry, and optical and NIR spectroscopy of Type Iax supernova 2012Z. The data set consists of both early and late-time observations, including the first late phase NIR spectrum obtained for a spectroscopically classified SN Iax. Simple model calculations of its bolometric light curve suggest SN 2012Z produced ~0.3 M_sun of (56)Ni, ejected about a Chandrasekhar mass of material, and had an explosion energy of ~10^51 erg, making it one of the brightest and most energetic SN Iax yet observed. The late phase NIR spectrum of SN 2012Z is found to broadly resemble similar epoch spectra of normal SNe Ia; however, like other SNe Iax, corresponding visual-wavelength spectra differ substantially compared to all supernova types. Constraints from the distribution of IMEs, e.g. silicon and magnesium, indicate that the outer ejecta did not experience significant mixing during or after burning, and the late phase NIR line profiles suggests most of the (56)Ni is produced during high d...

  6. Uniform Contribution of Supernova Explosions to the Chemical Enrichment of Abell 3112 out to R200

    CERN Document Server

    Ezer, Cemile; Ercan, E Nihal; Smith, Randall K; Bautz, Mark W; Loewenstein, Mike; McDonald, Mike; Miller, Eric D

    2016-01-01

    The spatial distribution of the metals residing in the intra-cluster medium (ICM) of galaxy clusters records all the information on a cluster's nucleosynthesis and chemical enrichment history. We present measurements from deep Suzaku and Chandra observations of the cool-core galaxy cluster Abell 3112 out its virial radius (~1470 kpc). We find that the ratio of the observed supernova type Ia explosions to the total supernova explosions have a uniform distribution at a level of 12-16% out to the cluster's virial radius. The non-varying supernova enrichment suggests that the ICM was enriched by metals at an early stage before the cluster itself was formed. We also find that the 2D delayed detonations models CDDT produce significantly worse fits to the X-ray spectra compared to simple 1D W7 models. This may indicate that CDDT explosions are not a dominant process of enriching the ICM.

  7. A New Estimation of Mass Accumulation Efficiency in Helium Shell Flashes toward Type Ia Supernova Explosions

    CERN Document Server

    Kato, M

    1999-01-01

    We have calculated the mass accumulation efficiency during helium shell flashes to examine whether or not a carbon-oxygen white dwarf (C+O WD) grows up to the Chandrasekhar mass limit to ignite a Type Ia supernova explosion. It has been frequently argued that luminous super-soft X-ray sources and symbiotic stars are progenitors of SNe Ia. In such systems, a C+O WD accretes hydrogen-rich matter from a companion and burns hydrogen steadily on its surface. The WD develops a helium layer underneath the hydrogen-rich envelope and undergoes periodic helium shell flashes. Using OPAL opacity, we have reanalyzed a full cycle of helium shell flashes on a 1.3 M_ødot C+O WD and confirmed that the helium envelope of the WD expands to blow a strong wind. A part of the accumulated matter is lost by the wind. The mass accumulation efficiency is estimated as \\eta_{He} = -0.175 (\\log accretion rate \\dot M is in units of M_ødot yr^{-1}. In relatively high mass accretion rates as expected in recent SN Ia progenitor models, the...

  8. METAMORPHOSIS OF SN 2014C: DELAYED INTERACTION BETWEEN A HYDROGEN POOR CORE-COLLAPSE SUPERNOVA AND A NEARBY CIRCUMSTELLAR SHELL

    Energy Technology Data Exchange (ETDEWEB)

    Milisavljevic, D.; Margutti, R.; Kamble, A.; Patnaude, D. J.; Raymond, J. C.; Challis, P.; Drout, M. R.; Grindlay, J. E.; Kirshner, R. P.; Lunnan, R.; Miller, G. F.; Parrent, J. T.; Sanders, N. E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA, 02138 (United States); Eldridge, J. J. [Department of Physics, University of Auckland, Private Bag 92019, Auckland (New Zealand); Fong, W. [Steward Observatory, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Bietenholz, M. [Hartebeesthoek Radio Observatory, P.O. Box 443, Krugersdorp 1740 (South Africa); Chornock, R. [Astrophysical Institute, Department of Physics and Astronomy, 251B Clippinger Lab, Ohio University, Athens, OH 45701 (United States); Fransson, C. [Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, SE106 91 Stockholm (Sweden); Fesen, R. A. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Lab, Hanover, NH 03755 (United States); Mackey, J., E-mail: dmilisav@cfa.harvard.edu [Argelander-Institut für Astronomie, Auf dem Hgel 71, D-53121 Bonn (Germany); and others

    2015-12-20

    We present optical observations of supernova SN 2014C, which underwent an unprecedented slow metamorphosis from H-poor type Ib to H-rich type IIn over the course of one year. The observed spectroscopic evolution is consistent with the supernova having exploded in a cavity before encountering a massive shell of the progenitor star’s stripped hydrogen envelope. Possible origins for the circumstellar shell include a brief Wolf–Rayet fast wind phase that overtook a slower red supergiant wind, eruptive ejection, or confinement of circumstellar material by external influences of neighboring stars. An extended high velocity Hα absorption feature seen in near-maximum light spectra implies that the progenitor star was not completely stripped of hydrogen at the time of core collapse. Archival pre-explosion Subaru Telescope Suprime-Cam and Hubble Space Telescope Wide Field Planetary Camera 2 images of the region obtained in 2009 show a coincident source that is most likely a compact massive star cluster in NGC 7331 that hosted the progenitor system. By comparing the emission properties of the source with stellar population models that incorporate interacting binary stars we estimate the age of the host cluster to be 30–300 Myr, and favor ages closer to 30 Myr in light of relatively strong Hα emission. SN 2014C is the best observed member of a class of core-collapse supernovae that fill the gap between events that interact strongly with dense, nearby environments immediately after explosion and those that never show signs of interaction. Better understanding of the frequency and nature of this intermediate population can contribute valuable information about the poorly understood final stages of stellar evolution.

  9. Lightcurves of thermonuclear supernovae as a probe of the explosion mechanism and their use in cosmology

    CERN Document Server

    Blinnikov, S I

    2002-01-01

    Thermonuclear supernovae are valuable for cosmology but their physics is not yet fully understood. Modeling the development and propagation of nuclear flame is complicated by numerous instabilities. The predictions of supernova light curves still involve some simplifying assumptions, but one can use the comparison of the computed fluxes with observations to constrain the explosion mechanism. In spite of great progress in recent years, a number of issues remains unsolved both in flame physics and light curve modeling.

  10. Massive Computation for Understanding Core-Collapse Supernova Explosions

    CERN Document Server

    Ott, Christian D

    2016-01-01

    How do massive stars explode? Progress toward the answer is driven by increases in compute power. Petascale supercomputers are enabling detailed three-dimensional simulations of core-collapse supernovae. These are elucidating the role of fluid instabilities, turbulence, and magnetic field amplification in supernova engines.

  11. SN 1978K: The first millimetre detection of an evolved supernova outside of our Local Group

    CERN Document Server

    Ryder, S D; Smith, I A; Tingay, S J; Kool, E C; Polshaw, J

    2016-01-01

    Supernova 1978K is one of the oldest-known examples of the class of Type IIn supernovae that show evidence for strong interaction between the blast wave and a dense, pre-existing circumstellar medium. Here we report detections of SN 1978K at both 34 GHz and 94 GHz, making it only the second extragalactic supernova after SN 1987A to be detected at late-times at these frequencies. We find SN 1978K to be >400 times more luminous than SN 1987A at millimetre wavelengths in spite of the roughly nine year difference in ages, highlighting the risk in adopting SN 1987A as a template for the evolution of core-collapse supernovae in general. Additionally, from new VLBI observations at 8.4 GHz, we measure a deconvolved diameter for SN 1978K of ~5 milli-arcsec, and a corresponding average expansion velocity of <1500 km/s. These observations provide independent evidence of an extremely dense circumstellar medium surrounding the progenitor star.

  12. Possibility of Systematic Study of Supernova Explosions by Nuclear Imaging Spectroscopy

    CERN Document Server

    Mizumura, Yoshitaka; Takada, Atsushi

    2016-01-01

    An all-sky monitor with nuclear imaging spectroscopy is a promising tool for the systematic study of supernova explosions. In particular, progenitor scenarios of type-Ia supernovae, which are not yet well understood, can be resolved using light curves in the nuclear gamma-ray band. Here we report an expected result of an all-sky monitor with imaging spectroscopy using electron-tracking Compton camera, which will enable us to observe nuclear gamma-ray lines from type-Ia supernovae.

  13. SALT spectroscopic classification of SN 2017azk (= PS17bii) as a type-Ia supernova near maximum light

    Science.gov (United States)

    Jha, S. W.; Dettman, K.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Vaisanen, P.

    2017-02-01

    We obtained SALT (+RSS) spectroscopy of SN 2017azk (= PS17bii) on 2017 Feb 24.0 UT, covering the wavelength range 340-920 nm. Cross-correlation of the supernova spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows SN 2017azk is a type-Ia supernova near maximum light.

  14. SALT spectroscopic classification of SN 2017erp as a type-Ia supernova well before maximum light

    Science.gov (United States)

    Jha, S. W.; Camacho, Y.; Dettman, K.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Skelton, R.

    2017-06-01

    We obtained SALT (+RSS) spectroscopy of SN 2017erp (discovered by K. Itagaki) on 2017 Jun 13.9 UT, covering the wavelength range 350-940 nm. Cross-correlation of the supernova spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows SN 2017erp is a type-Ia supernova before maximum light.

  15. Nucleosynthesis from Supernovae as a Function of Explosion Energy from NuGrid

    CERN Document Server

    Fryer, Christopher L; Bennett, Michael; Diehl, Steven; Herwig, Falk; Hirschi, Raphael; Hungerford, Aimee; Pignatari, Marco; Magkotsios, Georgios; Rockefeller, Gabriel; Timmes, Francis X

    2008-01-01

    We review some of the uncertainties in calculating nucleosynthetic yields, focusing on the explosion mechanism. Current yield calculations tend to either use a piston, energy injection, or enhancement of neutrino opacities to drive an explosion. We show that the energy injection, or more accurately, an entropy injection mechanism is best-suited to mimic our current understanding of the convection-enhanced supernova engine. The enhanced neutrino-opacity technique is in qualitative disagreement with simulations of core-collapse supernovae and will likely produce errors in the yields. But piston-driven explosions are the most discrepant. Piston-driven explosion severely underestimate the amount of fallback, leading to order-of-magnitude errors in the yields of heavy elements. To obtain yields accurate to the factor of a few level, we must use entropy or energy injection and this has become the NuGrid collaboration approach.

  16. Himalayan Chandra Telescope Observations of Type-Ia Supernova SN 2010at

    Science.gov (United States)

    Patel, Brandon; Anupama, G.; Sahu, D. K.

    2012-01-01

    We present BVRI photometry and spectroscopy of Type Ia Supernova SN 2010at. SN 2010at is located in the MCG+13-09-010 galaxy (z =0.04) and was discovered on 03-19-2010. Our analysis focuses on the follow up observations taken with the 2-meter Himalayan Chandra Telescope from 2010-03-21 to 2010-05-24. We present the light curve and color evolution of SN 2010at, along with MLCS2k2 and SALT-II light curve fits. We find that SN 2010at's color and photometric evolution are similar to SN 1999ac, but SN 2010at is brighter at maximum. Spectroscopically, SN 2010at appears to be normal at early times. This work was funded by the National Science Foundation's Office of International Science and Education, Grant Number 0854436: International Research Experience for Students, and managed by the National Solar Observatory's Global Oscillation Network.

  17. SN2003bg: a broad-lined Type IIb Supernova with Hydrogen

    CERN Document Server

    Mazzali, Paolo A; Hamuy, Mario; Nomoto, Ken'ichi

    2009-01-01

    Models for the spectra and the light curve, in the photospheric as well as in the late nebular phase, are used to infer the properties of the very radio-bright, broad-lined type IIb Supernova 2003bg. Consistent fits to the light curve and the spectral evolution are obtained with an explosion that ejected ~ 4 M_sun of material with a kinetic energy of ~ 5 10^51 erg. A thin layer of hydrogen, comprising ~ 0.05 M_sun, is inferred to be present in the ejecta at the highest velocities (v >~ 9000 km/s), while a thicker helium layer, comprising ~ 1.25 M_sun, was ejected at velocities between 6500 and 9000 km/s. At lower velocities, heavier elements are present, including ~ 0.2 M_sun of 56Ni that shape the light curve and the late-time nebular spectra. These values suggest that the progenitor star had a mass of ~ 20-25 M_sun (comparable to, but maybe somewhat smaller than that of the progenitor of the XRF/SN 2008D). The rather broad-lined early spectra are the result of the presence of a small amount of material (~ 0...

  18. SN 2015BN: A Detailed Multi-wavelength View of a Nearby Superluminous Supernova

    Science.gov (United States)

    Nicholl, M.; Berger, E.; Smartt, S. J.; Margutti, R.; Kamble, A.; Alexander, K. D.; Chen, T.-W.; Inserra, C.; Arcavi, I.; Blanchard, P. K.; Cartier, R.; Chambers, K. C.; Childress, M. J.; Chornock, R.; Cowperthwaite, P. S.; Drout, M.; Flewelling, H. A.; Fraser, M.; Gal-Yam, A.; Galbany, L.; Harmanen, J.; Holoien, T. W.-S.; Hosseinzadeh, G.; Howell, D. A.; Huber, M. E.; Jerkstrand, A.; Kankare, E.; Kochanek, C. S.; Lin, Z.-Y.; Lunnan, R.; Magnier, E. A.; Maguire, K.; McCully, C.; McDonald, M.; Metzger, B. D.; Milisavljevic, D.; Mitra, A.; Reynolds, T.; Saario, J.; Shappee, B. J.; Smith, K. W.; Valenti, S.; Villar, V. A.; Waters, C.; Young, D. R.

    2016-07-01

    We present observations of SN 2015bn (=PS15ae = CSS141223-113342+004332 = MLS150211-113342+004333), a Type I superluminous supernova (SLSN) at redshift z = 0.1136. As well as being one of the closest SLSNe I yet discovered, it is intrinsically brighter ({M}U≈ -23.1) and in a fainter galaxy ({M}B≈ -16.0) than other SLSNe at z˜ 0.1. We used this opportunity to collect the most extensive data set for any SLSN I to date, including densely sampled spectroscopy and photometry, from the UV to the NIR, spanning -50 to +250 days from optical maximum. SN 2015bn fades slowly, but exhibits surprising undulations in the light curve on a timescale of 30-50 days, especially in the UV. The spectrum shows extraordinarily slow evolution except for a rapid transformation between +7 and +20-30 days. No narrow emission lines from slow-moving material are observed at any phase. We derive physical properties including the bolometric luminosity, and find slow velocity evolution and non-monotonic temperature and radial evolution. A deep radio limit rules out a healthy off-axis gamma-ray burst, and places constraints on the pre-explosion mass loss. The data can be consistently explained by a ≳ 10 M {}⊙ stripped progenitor exploding with ˜ {10}51 erg kinetic energy, forming a magnetar with a spin-down timescale of ˜20 days (thus avoiding a gamma-ray burst) that reheats the ejecta and drives ionization fronts. The most likely alternative scenario—interaction with ˜20 M {}⊙ of dense, inhomogeneous circumstellar material—can be tested with continuing radio follow-up.

  19. iPTF13beo: The Double-Peaked Light Curve of a Type Ibn Supernova Discovered Shortly after Explosion

    CERN Document Server

    Gorbikov, Evgeny; Ofek, Eran O; Vreeswijk, Paul M; Nugent, Peter E; Chotard, Nicolas; Kulkarni, Shrinivas R; Cao, Yi; De Cia, Annalisa; Yaron, Ofer; Tal, David; Arcavi, Iair; Kasliwal, Mansi M; Cenko, S Bradley; Sullivan, Mark

    2013-01-01

    We present optical photometric and spectroscopic observations of the Type Ibn (SN 2006jc-like) supernova iPTF13beo. Detected by the intermediate Palomar Transient Factory on 2013 May 19.39, ~3 hours after the estimated explosion time, iPTF13beo is the youngest and the most distant (430 Mpc) Type Ibn event ever observed. Type Ibn events are rare, and their early evolution, both photometric and spectroscopic, has not been studied yet. The iPTF13beo light curve is consistent with light curves of other Type Ibn SNe and with light curves of fast Type Ic events, but with a slightly faster rise-time of two days. In addition, the iPTF13beo light curve exhibits a double-peak structure separated by 9 days, not observed before in any Type Ibn SN. Low-resolution spectra were obtained during the two peaks of the iPTF13beo light curve. The spectrum taken during the rising stage (2.4 days after the estimated explosion time) is featureless and similar to early spectra of SNe Ic-BL. The spectrum obtained during the declining ...

  20. PTF11eon/SN2011dh: Discovery of a Type IIb Supernova From a Compact Progenitor in the Nearby Galaxy M51

    CERN Document Server

    Arcavi, Iair; Yaron, Ofer; Sternberg, Assaf; Rabinak, Itay; Waxman, Eli; Kasliwal, Mansi M; Quimby, Robert M; Ofek, Eran O; Horesh, Assaf; Kulkarni, Shrinivas R; Filippenko, Alexei V; Silverman, Jeffrey M; Cenko, S Bradley; Li, Weidong; Bloom, Joshua S; Sullivan, Mark; Fox, Derek B; Nugent, Peter E; Poznanski, Dovi; Gorbikov, Evgeny; Riou, Amedee; Lamotte-Bailey, Stephane; Griga, Thomas; Cohen, Judith G; Polishook, David; Xu, Dong; Ben-Ami, Sagi; Manulis, Ilan; Walker, Emma S; Mazzali, Paulo A; Pian, Elena; Matheson, Thomas; Maquire, Kate; Pan, Yen-Chen; Bersier, David; James, Philip; Marchant, Jonathan M; Smith, Robert J; Mottram, Chris J; Barnsley, Robert M; Kandrashoff, Michael T; Clubb, Kelsey I

    2011-01-01

    On May 31, 2011 UT a supernova (SN) exploded in the nearby galaxy M51 (the Whirlpool Galaxy). We discovered this event using small telescopes equipped with CCD cameras, as well as by the Palomar Transient Factory (PTF) survey, and rapidly confirmed it to be a Type II supernova. Our early light curve and spectroscopy indicates that PTF11eon resulted from the explosion of a relatively compact progenitor star as evidenced by the rapid shock-breakout cooling seen in the light curve, the relatively low temperature in early-time spectra and the prompt appearance of low-ionization spectral features. The spectra of PTF11eon are dominated by H lines out to day 10 after explosion, but initial signs of He appear to be present. Assuming that He lines continue to develop in the near future, this SN is likely a member of the cIIb (compact IIb; Chevalier and Soderberg 2010) class, with progenitor radius larger than that of SN 2008ax and smaller than the eIIb (extended IIb) SN 1993J progenitor. Our data imply that the object...

  1. The critical mass ratio of double white dwarf binaries for violent merger-induced Type Ia supernova explosions

    CERN Document Server

    Sato, Yushi; Tanikawa, Ataru; Nomoto, Ken'ichi; Maeda, Keiichi; Hachisu, Izumi

    2016-01-01

    Mergers of carbon-oxygen (CO) white dwarfs (WDs) are considered as one of the potential progenitors of type Ia supernovae (SNe Ia). Recent hydrodynamical simulations showed that the less massive (secondary) WD violently accretes onto the more massive (primary) one, carbon detonation occurs, the detonation wave propagates through the primary, and the primary finally explodes as a sub-Chandrasekhar mass SN Ia. Such an explosion mechanism is called the violent merger scenario. Based on the smoothed particle hydrodynamics (SPH) simulations of merging CO WDs, we derived more stringent critical mass ratio (qcr) leading to the violent merger scenario than the previous results. We conclude that this difference mainly comes from the differences in the initial condition, synchronously spinning of WDs or not. Using our new results, we estimated the brightness distribution of SNe Ia in the violent merger scenario and compared it with previous studies. We found that our new qcr does not significantly affect the brightness...

  2. Nearby Supernova Factory Observations of SN 2005gj: Another Type Ia Supernova in a Massive Circumstellar Envelope

    CERN Document Server

    Aldering, G; Bailey, S; Baltay, C; Bauer, A; Blanc, N; Bongard, S; Copin, Y; Gangler, E; Gilles, S; Kessler, R; Kocevski, D; Lee, B C; Loken, S; Nugent, P; Pain, R; Pécontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigaudier, G; Scalzo, R; Smadja, G; Thomas, R C; Wang, L; Weaver, B A

    2006-01-01

    We report Nearby Supernova Factory observations of SN 2005gj, the second confirmed case of a "hybrid" Type Ia/IIn supernova. Our early-phase photometry of SN 2005gj shows that the interaction is much stronger than for the prototype, SN 2002ic. Our first spectrum shows a hot continuum with broad and narrow H-alpha emission. Later spectra, spanning over 4 months from outburst, show clear Type Ia features combined with broad and narrow H-gamma, H-beta, H-alpha and HeI 5876,7065 in emission. At higher resolution, P Cygni profiles are apparent. Surprisingly, we also observe an inverted P Cygni profile for [OIII] 5007. We find that the lightcurve and measured velocity of the unshocked circumstellar material imply mass loss as recently as 8 years ago. The early lightcurve is well-described by a flat radial density profile for the circumstellar material. However, our decomposition of the spectra into Type Ia and shock emission components allows for little obscuration of the supernova, suggesting an aspherical or clum...

  3. Mass-loss histories of Type IIn supernova progenitors within decades before their explosion

    CERN Document Server

    Moriya, Takashi J; Taddia, Francesco; Sollerman, Jesper; Blinnikov, Sergei I; Sorokina, Elena I

    2014-01-01

    We present results of a systematic study of the mass-loss properties of Type IIn supernova progenitors within decades before their explosion. We apply an analytic light curve model to 11 Type IIn supernova bolometric light curves to derive the circumstellar medium properties. We reconstruct the mass-loss histories based on the estimated circumstellar medium properties. The estimated mass-loss rates are mostly higher than 1e-3 Msun/yr and they are consistent with those obtained by other methods. The mass-loss rates are often found to be constantly high within decades before their explosion. This indicates that there exists some mechanism to sustain the high mass-loss rates of Type IIn supernova progenitors for at least decades before their explosion. Thus, the shorter eruptive mass loss events observed in some Type IIn supernova progenitors are not always responsible for creating their dense circumstellar media. In addition, we find that Type IIn supernova progenitors may tend to increase their mass-loss rates...

  4. Fast evolving pair-instability supernova models: evolution, explosion, light curves

    CERN Document Server

    Kozyreva, Alexandra; Hirschi, Raphael; Frohlich, Carla; Blinnikov, Sergey; Wollaeger, Ryan T; Noebauer, Ulrich M; van Rossum, Daniel R; Heger, Alexander; Even, Wesley P; Waldman, Roni; Tolstov, Alexey; Chatzopoulos, Emmanouil; Sorokina, Elena

    2016-01-01

    With an increasing number of superluminous supernovae (SLSNe) discovered the question of their origin remains open and causes heated debates in the supernova community. Currently, there are three proposed mechanisms for SLSNe: (1) pair-instability supernovae (PISN), (2) magnetar-driven supernovae, and (3) models in which the supernova ejecta interacts with a circumstellar material ejected before the explosion. Based on current observations of SLSNe, the PISN origin has been disfavoured for a number of reasons. Many PISN models provide overly broad light curves and too reddened spectra, because of massive ejecta and a high amount of nickel. In the current study we re-examine PISN properties using progenitor models computed with the GENEC code. We calculate supernova explosions with FLASH and light curve evolution with the radiation hydrodynamics code STELLA. We find that high-mass models (200 and 250 solar masses) at relatively high metallicity (Z=0.001) do not retain hydrogen in the outer layers and produce r...

  5. Fast evolving pair-instability supernova models: evolution, explosion, light curves

    Science.gov (United States)

    Kozyreva, Alexandra; Gilmer, Matthew; Hirschi, Raphael; Fröhlich, Carla; Blinnikov, Sergey; Wollaeger, Ryan T.; Noebauer, Ulrich M.; van Rossum, Daniel R.; Heger, Alexander; Even, Wesley P.; Waldman, Roni; Tolstov, Alexey; Chatzopoulos, Emmanouil; Sorokina, Elena

    2017-01-01

    With an increasing number of superluminous supernovae (SLSNe) discovered, the question of their origin remains open and causes heated debates in the supernova community. Currently, there are three proposed mechanisms for SLSNe: (1) pair-instability supernovae (PISNe), (2) magnetar-driven supernovae and (3) models in which the supernova ejecta interacts with a circumstellar material ejected before the explosion. Based on current observations of SLSNe, the PISN origin has been disfavoured for a number of reasons. Many PISN models provide overly broad light curves and too reddened spectra, because of massive ejecta and a high amount of nickel. In the current study, we re-examine PISN properties using progenitor models computed with the GENEC code. We calculate supernova explosions with FLASH and light-curve evolution with the radiation hydrodynamics code STELLA. We find that high-mass models (200 and 250 M⊙) at relatively high metallicity (Z = 0.001) do not retain hydrogen in the outer layers and produce relatively fast evolving PISNe Type I and might be suitable to explain some SLSNe. We also investigate uncertainties in light-curve modelling due to codes, opacities, the nickel-bubble effect and progenitor structure and composition.

  6. Fast evolving pair-instability supernova models: Evolution, explosion, light curves

    Science.gov (United States)

    Kozyreva, Alexandra; Gilmer, Matthew; Hirschi, Raphael; Fröhlich, Carla; Blinnikov, Sergey; Wollaeger, Ryan T.; Noebauer, Ulrich M.; van Rossum, Daniel R.; Heger, Alexander; Even, Wesley P.; Waldman, Roni; Tolstov, Alexey; Chatzopoulos, Emmanouil; Sorokina, Elena

    2016-10-01

    With an increasing number of superluminous supernovae (SLSNe) discovered the question of their origin remains open and causes heated debates in the supernova community. Currently, there are three proposed mechanisms for SLSNe: (1) pair-instability supernovae (PISN), (2) magnetar-driven supernovae, and (3) models in which the supernova ejecta interacts with a circumstellar material ejected before the explosion. Based on current observations of SLSNe, the PISN origin has been disfavoured for a number of reasons. Many PISN models provide overly broad light curves and too reddened spectra, because of massive ejecta and a high amount of nickel. In the current study we re-examine PISN properties using progenitor models computed with the GENEC code. We calculate supernova explosions with FLASH and light curve evolution with the radiation hydrodynamics code STELLA. We find that high-mass models (200 M⊙ and 250 M⊙) at relatively high metallicity (Z = 0.001) do not retain hydrogen in the outer layers and produce relatively fast evolving PISNe Type I and might be suitable to explain some SLSNe. We also investigate uncertainties in light curve modelling due to codes, opacities, the nickel-bubble effect and progenitor structure and composition.

  7. OPTICAL OBSERVATIONS OF THE TYPE IA SUPERNOVA SN 2011fe IN M101 FOR NEARLY 500 DAYS

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Kaicheng; Wang, Xiaofeng; Zhao, Xulin; Chen, Jia; Chen, Juncheng; Huang, Fang; Mo, Jun; Rui, Liming; Song, Hao; Sai, Hanna; Li, Wenxiong [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing, 100084 (China); Zhang, JuJia; Bai, Jinming [Yunnan Astronomical Observatory of China, Chinese Academy of Sciences, Kunming, 650011 (China); Zhang, Tianmeng; Wu, Chao [National Astronomical Observatory of China, Chinese Academy of Sciences, Beijing, 100012 (China); Ganeshalingam, Mohan; Li, Weidong; Filippenko, Alexei V.; Zheng, Weikang [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Wang, Lifan, E-mail: wang_xf@mail.tsinghua.edu.cn [Physics and Astronomy Department, Texas A and M University, College Station, TX 77843 (United States)

    2016-03-20

    We present well-sampled optical observations of the bright Type Ia supernova (SN Ia) SN 2011fe in M101. Our data, starting from ∼16 days before maximum light and extending to ∼463 days after maximum, provide an unprecedented time series of spectra and photometry for a normal SN Ia. Fitting the early-time rising light curve, we find that the luminosity evolution of SN 2011fe follows a t{sup n} law, with the index n being close to 2.0 in the VRI bands but slightly larger in the U and B bands. Combining the published ultraviolet (UV) and near-infrared (NIR) photometry, we derive the contribution of UV/NIR emission relative to the optical. SN 2011fe is found to have stronger UV emission and reaches its UV peak a few days earlier than other SNe Ia with similar Δm{sub 15}(B), suggestive of less trapping of high-energy photons in the ejecta. Moreover, the U-band light curve shows a notably faster decline at late phases (t ≈ 100–300 days), which also suggests that the ejecta may be relatively transparent to UV photons. These results favor the notion that SN 2011fe might have a progenitor system with relatively lower metallicity. On the other hand, the early-phase spectra exhibit prominent high-velocity features (HVFs) of O i λ7773 and the Ca ii NIR triplet, but only barely detectable in Si ii 6355. This difference can be caused by either an ionization/temperature effect or an abundance enhancement scenario for the formation of HVFs; it suggests that the photospheric temperature of SN 2011fe is intrinsically low, perhaps owing to incomplete burning during the explosion of the white dwarf.

  8. Heavy Element Nucleosynthesis in the MHD Jet Explosions of Core-Collapse Supernovae

    CERN Document Server

    Nishimura, Nobuya; Fujimoto, Shin-ichirou; Kotake, Kei; Yamada, Shoichi

    2006-01-01

    For the rst time heavy element nucleosynthesis in the magneto-hydrodynamical (MHD) explosions of core-collapse supernovae are investigated using a massive star of 13M. in a main sequence stage. Contrary to the case of the spherical explosion, jet-like explosion due to the combined effects of the rotation and magnetic eld lowers the electron fraction signi cantly inside the layers above the Fe-core. Then, the anisotropic shock waves pass through the oxygen rich layers. As a consequence, we nd that the nucleosynthesis of the r- and p-process proceeds appreciably compared to the models previously considered.

  9. Two Type Ic supernovae in low-metallicity, dwarf galaxies: diversity of explosions

    CERN Document Server

    Young, D R; Valenti, S; Pastorello, A; Benetti, S; Benn, C R; Bersier, D; Botticella, M T; Corradi, R L M; Harutyunyan, A H; Hrudkova, M; Hunter, I; Mattila, S; de Mooij, E J W; Navasardyan, H; Snellen, I A G; Tanvir, N R; Zampieri, L

    2009-01-01

    We present BVRI photometry and optical spectroscopy of two Type Ic supernovae SN 2007bg and SN 2007bi discovered in wide-field, non-targeted surveys and associated with sub-luminous blue dwarf galaxies. Neither SNe 2007bg nor 2007bi were found in association with an observed GRB, but are found to inhabit similar low-metallicity environments as GRB associated supernovae. The radio-bright SN 2007bg is hosted by an extremely sub-luminous galaxy of magnitude MB = -12.4+/-0.6 mag with an estimated oxygen abundance of 12+log(O/H) = 8.18+/-0.17. The lightcurve of SN 2007bg displays one of the fastest post-maximum decline rates of all broad-lined Type Ic supernovae known to date and, when combined with its high expansion velocities, a high kinetic energy to ejected mass ratio (E_K/Mej ~ 2.7). We show that SN 2007bi is possibly the most luminous Type Ic known, reaching a peak magnitude of MR ~ 21.3 mag and displays a remarkably slow decline, following the radioactive decay rate of 56Co to 56Fe throughout the course of...

  10. Hubble Space Telescope spectra of the type Ia supernova SN 2011fe: A low-energy delayed detonation of a white dwarf with Z

    CERN Document Server

    Mazzali, Paolo; Hachinger, Stephan; Ellis, Richard; Nugent, Peter E; Howell, D Andrew; Gal-Yam, Avishay; Maguire, Kate; Cooke, Jeff; Thomas, Rollin

    2013-01-01

    Hubble Space Telescope spectroscopic observations of the nearby type Ia supernova (SN Ia) SN 2011fe, taken on 10 epochs from -13.5 to +41 days relative to B-band maximum light, and spanning the far-ultraviolet (UV) to the near-infrared (IR) are presented. This spectroscopic coverage makes SN 2011fe the best-studied local SN Ia to date. SN 2011fe is a typical moderately-luminous SN Ia with no evidence for dust extinction. Its near-UV spectral properties are representative of a larger sample of local events studied in Maguire et al. (2012). As a result, conclusions inferred from our detailed investigations are likely representative of those for other normal SNe Ia. The near-UV to optical spectra of SN 2011fe are modelled with a Monte Carlo radiative transfer code using the technique of 'abundance tomography', providing tight constraints on the density structure and abundance stratification of the event. SN 2011fe was a relatively weak explosion, with moderate Fe-group yields. Although its density structure is c...

  11. The explosion sites of nearby supernovae seen with integral field spectroscopy

    Science.gov (United States)

    Kuncarayakti, Hanindyo

    Integral field spectroscopy of nearby supernova sites within ~30 Mpc have been obtained using multiple IFU spectrographs in Hawaii and Chile. This technique enables both spatial and spectral information of the explosion sites to be acquired simultaneously, thus providing the identification of the parent stellar population of the supernova progenitor and the estimates for its physical parameters including age and metallicity via the spectrum. While this work has mainly been done in the optical wavelengths using instruments such as VIMOS, GMOS, and MUSE, a near-infrared approach has also been carried out using the AO-assisted SINFONI. By studying the supernova parent stellar population, we aim to characterize the mass and metallicity of the progenitors of different types of supernovae.

  12. 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.

  13. Discovery of a Supernova Explosion at Half the Age of the Universe and its Cosmological Implications

    Science.gov (United States)

    Perlmutter, S.; Aldering, G.; Della Valle, M.; Deustua, S.; Ellis, R. S.; Fabbro, S.; Fruchter, A.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hook, I. M.; Kim, A. G.; Kim, M. Y.; Knop, R. A.; Lidman, C.; McMahon, R. G.; Nugent, P.; Pain, R.; Panagia, N.; Pennypacker, C. R.; Ruiz-Lapuente, P.; Schaefer, B.; Walton, N.

    1997-12-16

    The ultimate fate of the universe, infinite expansion or a big crunch, can be determined by measuring the redshifts, apparent brightnesses, and intrinsic luminosities of very distant supernovae. Recent developments have provided tools that make such a program practicable: (1) Studies of relatively nearby Type la supernovae (SNe la) have shown that their intrinsic luminosities can be accurately determined; (2) New research techniques have made it possible to schedule the discovery and follow-up observations of distant supernovae, producing well over 50 very distant (z = 0.3-0.7) SNe Ia to date. These distant supernovae provide a record of changes in the expansion rate over the past several billion years. By making precise measurements of supernovae at still greater distances, and thus extending this expansion history back far enough in time, we can even distinguish the slowing caused by the gravitational attraction of the universe's mass density {Omega}{sub M} from the effect of a possibly inflationary pressure caused by a cosmological constant {Lambda}. We report here the first such measurements, with our discovery of a Type Ia supernova (SN 1997ap) at z = 0.83. Measurements at the Keck II 10-m telescope make this the most distant spectroscopically confirmed supernova. Over two months of photometry of SN 1997ap with the Hubble Space Telescope and ground-based telescopes, when combined with previous measurements of nearer SNe la, suggests that we may live in a low mass-density universe. Further supernovae at comparable distances are currently scheduled for ground and space-based observations.

  14. Nearby supernova host galaxies from the CALIFA Survey: II. SN environmental metallicity

    CERN Document Server

    Galbany, L; Mourão, A M; Rodrigues, M; Flores, H; Walcher, C J; Sánchez, S F; García-Benito, R; Mast, D; Badenes, C; Delgado, R M González; Kehrig, C; Lyubenova, M; Marino, R A; Mollá, M; Meidt, S; Pérez, E; van de Ven, G; Vílchez, J M

    2016-01-01

    The metallicity of a supernova (SN) progenitor, together with its mass, is one of the main parameters that rules their outcome. We present a metallicity study of 115 nearby SN host galaxies (0.00510 dex) by targeted searches. We also found no evidence that the metallicity at the SN location differs from the average metallicity at the GCD of the SNe. By extending our SN sample with published metallicities at the SN location, we studied the metallicity distributions for all SN subtypes split into SN discovered in targeted and untargeted searches. We confirm a bias toward higher host masses and metallicities in the targeted searches. Combining data from targeted and untargeted searches we found a sequence from higher to lower local metallicity: SN Ia, Ic, and II show the highest metallicity, which is significantly higher than SN Ib, IIb, and Ic-BL. Our results support the picture of SN Ib resulting from binary progenitors and, at least part of, SN Ic being the result of single massive stars stripped of their out...

  15. Classification of SN 2016gmg (=PTSS-16opy), as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Xin, Yuxin; Chang, Liang; Wang, Jianguo; Wang, Xiaofeng; Li, Wenxiong; Yang, Zesheng; Li, Bin; Xu, Zhijian; Zhao, Haibin; Wang, Lifan

    2016-09-01

    We obtained an optical spectrum (range 340-900 nm) of SN 2016gmg (=PTSS-16opy), discovered by the PMO-Tsinghua Supernova Survey (PTSS: http://119.78.210.3/ptss2/), on UT Sep. 29.55 2016 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Observatory of Yunnan Observatories (YNAO).

  16. Spectroscopic Classification of SN 2017cne as a Type Ia Supernova

    Science.gov (United States)

    Xiang, Danfeng; Rui, Liming; Wang, Xiaofeng; Xu, Zhijian; Li, Wenxiong; Yang, Zesheng; Li, Bin; Tan, Hanjie; Zhao, Haibin; Wang, Lifan; Meng, Xianmin; Wang, J.; Jia, Junjun; Zhang, Tianmeng; Zhang, Jujia

    2017-04-01

    We obtained an optical spectrum (range 360-840 nm) of SN 2017cne (=PTSS-17ntl),discovered by PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Mar.31.76 2017 with the 2.16-m telescope (+BFOSC) at Xinglong Station of National Astronomical Observatories of China (NAOC).

  17. Spectroscopic Classification of SN 2017ejd (=PTSS-17tal) as a Type Ia Supernova

    Science.gov (United States)

    Xiang, Danfeng; Zhang, Kaicheng; Rui, Liming; Wang, Xiaofeng; Li, Wenxiong; Tan, Hanjie; Li, Bin; Xu, Zhijian; Zhao, Haibin; Wang, Lifan; Jia, Junjun; Zhang, Tianmeng; Xiao, Jujia Zhang Feng; Zhang, Tianmeng; Zhang, Jujia

    2017-05-01

    We obtained an optical spectrum (range 360-850 nm) of SN 2017ejd(=PTSS-17tal), discovered by the PMO-Tsinghua Supernova Survey (PTSS,http://www.cneost.org/ptss/ ), on UT May 30.7 2017 with the 2.16-m telescope (+BFOSC) at Xinglong Station of National Astronomical Observatories of China (NAOC).

  18. Spectroscopic Classification of SN 2016jdw as a Type Ib Supernova

    Science.gov (United States)

    Zhang, Jujia; Yu, Xiaoguang; Wang, Xiaofeng; Li, Wenxiong; Rui, Liming; Xu, Zhijian; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie

    2016-12-01

    We obtained an optical spectrum (range 340-900 nm) of SN 2016jdw (=PTSS-16sjp), discovered by the PMO-Tsinghua Supernova Survey (PTSS), on UT Dec.30.9 2016 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Observatory of Yunnan Observatories (YNAO).

  19. Spectroscopic Classification of SN 2017mt as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Xin, Yuxin; Wang, Xiaofeng; Li, Wenxiong; Rui, Liming; Xu, Zhijian; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Xiao, Feng; Zhang, Tianmeng

    2017-01-01

    We obtained an optical spectrum (range 370-870 nm) of SN 2017mt, discovered by the PMO-Tsinghua Supernova Survey (PTSS), on UT Jan.27.9 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Observatory of Yunnan Observatories (YNAO).

  20. Spectroscopic Classification of SN 2017dgi (=PTSS-17qjg) as a Type Ia Supernova

    Science.gov (United States)

    Xiang, Danfeng; Rui, Liming; Wang, Xiaofeng; Li, Wenxiong; Tan, Hanjie; Xu, Zhijian; Li, Bin; Zhao, Haibin; Wang, Lifan; Yang, Qian; Wu, Xuebin; Jia, Junjun; Zhang, Tianmeng; Yang, Zesheng; Zhang, Jujia

    2017-04-01

    We obtained an optical spectrum (range 390-830 nm) of SN 2017dgi (=PTSS-17qjg),discovered by PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Apr.23.56 2017 with the 2.16-m telescope (+BFOSC) at Xinglong Station of National Astronomical Observatories of China (NAOC).

  1. Spectroscopic Classification of SN 2017bke as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Zhang, Xiliang; Wang, Xiaofeng; Li, Wenxiong; Li, Bin; Xu, Zhijian; Tan, Hanjie; Zhao, Haibin; Wang, Lifan; Rui, Liming; ), Zesheng Yang

    2017-02-01

    We obtained an optical spectrum (range 340-880 nm) of SN 2017bke (=PTSS-17hcz),discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.25.7 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  2. Spectroscopic Classification of SN 2017mu as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Xin, Yuxin; Wang, Xiaofeng; Li, Wenxiong; Rui, Liming; Xu, Zhijian; Li, Bin; Zhao, Haibin; Wang, Lifan; Yang, Hanjie Tan Zesheng; Song, Hao

    2017-01-01

    We obtained an optical spectrum (range 340-800 nm) of SN 2017mu (=PTSS-17dgm), discovered by the PMO-Tsinghua Supernova Survey (PTSS), on UT Jan.26.7 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Observatory of Yunnan Observatories (YNAO).

  3. Spectroscopic Classification of SN 2017dkb (=PTSS-17slg) as a Type IIP Supernova

    Science.gov (United States)

    Zhang, Jujia; Yu, Xiaoguang; Li, Wenxiong; Wang, Xiaofeng; Tan, Hanjie; Li, Bin; Xu, Zhijian; Zhao, Haibin; Wang, Lifan; Xiang, Danfeng; Rui, Liming; Yang, Zesheng

    2017-05-01

    We obtained an optical spectrum (range 370-880 nm) of SN 2017dkb (=PTSS-17slg), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Apr.30.81 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  4. Spectroscopic Classification of SN 2017ckc as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Wang, Xiaofeng; Xu, Zhijian; Li, Wenxiong; Li, Bin; Yang, Zesheng; Tan, Hanjie; Zhao, Haibin; Wang, Lifan

    2017-04-01

    We obtained an optical spectrum (range 370-880 nm) of SN 2017ckc (=PTSS-17nip), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Apr.06.82 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  5. Spectroscopic Classification of SN 2017aap as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Xin, Yuxin; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Yang, Zesheng

    2017-02-01

    We obtained an optical spectrum (range 340-830 nm) of SN 2017aap (=PTSS-17die), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.02.9 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  6. Spectroscopic Classification of SN 2017ckp as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Wang, Xiaofeng; Xu, Zhijian; Li, Wenxiong; Li, Bin; Yang, Zesheng; Tan, Hanjie; Zhao, Haibin; Wang, Lifan

    2017-04-01

    We obtained an optical spectrum (range 340-900 nm) of SN 2017ckp (=PTSS-17npa), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Apr.05.82 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  7. Spectroscopic Classification of SN 2017aas as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Lu, Kaixin; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Yang, Zesheng

    2017-02-01

    We obtained an optical spectrum (range 340-830 nm) of SN 2017aas (=PTSS-17dib),discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.04.86 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  8. Spectroscopic Classification of SN 2017auu as a Young Type II Supernova

    Science.gov (United States)

    Zhang, Jujia; Lun, Baoli; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Yang, Zesheng

    2017-02-01

    We obtained an optical spectrum (range 340-860 nm) of SN 2017auu (=PTSS-17fhy),discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.16.5 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  9. Spectroscopic Classification of SN 2017ms as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Zheng, Xiangming; Wang, Xiaofeng; Li, Wenxiong; Rui, Liming; Xu, Zhijian; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Xiao, Feng; Zhang, Tianmeng

    2017-01-01

    We obtained an optical spectrum (range 330-870 nm) of SN 2017ms(= PTSS-17dfc), discovered by the PMO-Tsinghua Supernova Survey (PTSS), on UT Jan.23.88 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  10. Spectroscopic Classification of SN 2017cff (=PTSS-17nem) as a Young Type IIP Supernova

    Science.gov (United States)

    Zhang, Jujia; Xin, Yuxin; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Xiang, Danfeng

    2017-03-01

    We obtained an optical spectrum (range 340-900 nm) of SN 2017cff (=PTSS-17nem), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Mar.19.76 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  11. Spectroscopic Classification of SN 2017ckc as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Wang, Xiaofeng; Xu, Zhijian; Li, Wenxiong; Li, Bin; Yang, Zesheng; Tan, Hanjie; Zhao, Haibin; Wang, Lifan

    2017-04-01

    We obtained an optical spectrum (range 370-880 nm) of SN 2017ckc (=PTSS-17nip), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Apr.06.82 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  12. Spectroscopic Classification of SN 2017ckp as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Wang, Xiaofeng; Xu, Zhijian; Li, Wenxiong; Li, Bin; Yang, Zesheng; Tan, Hanjie; Zhao, Haibin; Wang, Lifan

    2017-04-01

    We obtained an optical spectrum (range 340-900 nm) of SN 2017ckp (=PTSS-17npa), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Apr.05.82 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  13. Spectroscopic Classification of SN 2017cne as a Type Ia Supernova

    Science.gov (United States)

    Xiang, Danfeng; Rui, Liming; Wang, Xiaofeng; Xu, Zhijian; Li, Wenxiong; Yang, Zesheng; Li, Bin; Tan, Hanjie; Zhao, Haibin; Wang, Lifan; Meng, Xianmin; Wang, J.; Jia, Junjun; Zhang, Tianmeng; Zhang, Jujia

    2017-04-01

    We obtained an optical spectrum (range 360-840 nm) of SN 2017cne (=PTSS-17ntl),discovered by PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Mar.31.76 2017 with the 2.16-m telescope (+BFOSC) at Xinglong Station of National Astronomical Observatories of China (NAOC).

  14. Supernova 2008J: early time observations of a heavily reddened SN 2002ic-like transient

    DEFF Research Database (Denmark)

    Taddia, F.; Stritzinger, M. D.; Phillips, M. M.

    2012-01-01

    Aims: We provide additional observational evidence that some Type Ia supernovae (SNe Ia) show signatures of circumstellar interaction (CSI) with hydrogen-rich material. Methods: Early phase optical and near-infrared (NIR) light curves and spectroscopy of SN 2008J obtained by the Carnegie Supernov...

  15. Spectroscopic Classification of SN 2017aap as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Xin, Yuxin; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Yang, Zesheng

    2017-02-01

    We obtained an optical spectrum (range 340-830 nm) of SN 2017aap (=PTSS-17die), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.02.9 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  16. Spectroscopic Classification of SN 2017aas as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Lu, Kaixin; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Yang, Zesheng

    2017-02-01

    We obtained an optical spectrum (range 340-830 nm) of SN 2017aas (=PTSS-17dib),discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.04.86 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  17. Spectroscopic Classification of SN 2017auu as a Young Type II Supernova

    Science.gov (United States)

    Zhang, Jujia; Lun, Baoli; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Yang, Zesheng

    2017-02-01

    We obtained an optical spectrum (range 340-860 nm) of SN 2017auu (=PTSS-17fhy),discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.16.5 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  18. Spectroscopic Classification of SN 2017cff (=PTSS-17nem) as a Young Type IIP Supernova

    Science.gov (United States)

    Zhang, Jujia; Xin, Yuxin; Xu, Zhijian; Li, Wenxiong; Wang, Xiaofeng; Li, Bin; Zhao, Haibin; Wang, Lifan; Tan, Hanjie; Rui, Liming; Xiang, Danfeng

    2017-03-01

    We obtained an optical spectrum (range 340-900 nm) of SN 2017cff (=PTSS-17nem), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Mar.19.76 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  19. Spectroscopic Classification of SN 2017bke as a Type Ia Supernova

    Science.gov (United States)

    Zhang, Jujia; Zhang, Xiliang; Wang, Xiaofeng; Li, Wenxiong; Li, Bin; Xu, Zhijian; Tan, Hanjie; Zhao, Haibin; Wang, Lifan; Rui, Liming; ), Zesheng Yang

    2017-02-01

    We obtained an optical spectrum (range 340-880 nm) of SN 2017bke (=PTSS-17hcz),discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT Feb.25.7 2017 with the 2.4 m telescope (LJT + YFOSC) at LiJiang Gaomeigu Observatory of Yunnan Observatories (YNAO).

  20. Supernova 2008J: early time observations of a heavily reddened SN 2002ic-like transient

    DEFF Research Database (Denmark)

    Taddia, F.; Stritzinger, M. D.; Phillips, M. M.;

    2012-01-01

    Aims: We provide additional observational evidence that some Type Ia supernovae (SNe Ia) show signatures of circumstellar interaction (CSI) with hydrogen-rich material. Methods: Early phase optical and near-infrared (NIR) light curves and spectroscopy of SN 2008J obtained by the Carnegie Supernov...

  1. SN 2010jl: Optical to hard X-ray observations reveal an explosion embedded in a ten solar mass cocoon

    Energy Technology Data Exchange (ETDEWEB)

    Ofek, Eran O.; Gal-Yam, Avishay; Arcavi, Iair [Benoziyo Center for Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel); Zoglauer, Andreas; Boggs, Steven E.; Barriére, Nicolas M. [Space Sciences Laboratory, Department of Physics, University of California, 7 Gauss Way, Berkeley, CA 94720 (United States); Reynolds, Stephen P. [Department of Physics, North Carolina State University, Raleigh, NC 27695-8202 (United States); Fryer, Chris L.; Even, Wesley [CCS Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Harrison, Fiona A.; Kulkarni, Shrinivas R.; Bellm, Eric; Grefenstette, Brian [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Cenko, S. Bradley; Bloom, Joshua S.; Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Christensen, Finn [DTU Space-National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Craig, William W.; Hailey, Charles J. [Columbia Astrophysics Laboratory, 538 West 120th Street, New York, NY 10027 (United States); Laher, Russ [Spitzer Science Center, MS 314-6, California Institute of Technology, Pasadena, CA 91125 (United States); and others

    2014-01-20

    Some supernovae (SNe) may be powered by the interaction of the SN ejecta with a large amount of circumstellar matter (CSM). However, quantitative estimates of the CSM mass around such SNe are missing when the CSM material is optically thick. Specifically, current estimators are sensitive to uncertainties regarding the CSM density profile and the ejecta velocity. Here we outline a method to measure the mass of the optically thick CSM around such SNe. We present new visible-light and X-ray observations of SN 2010jl (PTF 10aaxf), including the first detection of an SN in the hard X-ray band using NuSTAR. The total radiated luminosity of SN 2010jl is extreme—at least 9 × 10{sup 50} erg. By modeling the visible-light data, we robustly show that the mass of the circumstellar material within ∼10{sup 16} cm of the progenitor of SN 2010jl was in excess of 10 M {sub ☉}. This mass was likely ejected tens of years prior to the SN explosion. Our modeling suggests that the shock velocity during shock breakout was ∼6000 km s{sup –1}, decelerating to ∼2600 km s{sup –1} about 2 yr after maximum light. Furthermore, our late-time NuSTAR and XMM spectra of the SN presumably provide the first direct measurement of SN shock velocity 2 yr after the SN maximum light—measured to be in the range of 2000-4500 km s{sup –1} if the ions and electrons are in equilibrium, and ≳ 2000 km s{sup –1} if they are not in equilibrium. This measurement is in agreement with the shock velocity predicted by our modeling of the visible-light data. Our observations also show that the average radial density distribution of the CSM roughly follows an r {sup –2} law. A possible explanation for the ≳ 10 M {sub ☉} of CSM and the wind-like profile is that they are the result of multiple pulsational pair instability events prior to the SN explosion, separated from each other by years.

  2. Constraints on the Progenitor System of the Type Ia Supernova SN 2011fe/PTF11kly

    CERN Document Server

    Li, Weidong; Podsiadlowski, Philipp; Miller, Adam A; Cenko, S Bradley; Jha, Saurabh W; Sullivan, Mark; Howell, D Andrew; Nugent, Peter E; Butler, Nathaniel R; Ofek, Eran O; Kasliwal, Mansi M; Richards, Joseph W; Stockton, Alan; Shih, Hsin-Yi; Bildsten, Lars; Shara, Michael M; Bibby, Joanne; Filippenko, Alexei V; Ganeshalingam, Mohan; Silverman, Jeffrey M; Kulkarni, S R; Law, Nicholas M; Poznanski, Dovi; Quimby, Robert M; McCully, Curtis; Patel, Brandon; Maguire, Kate

    2011-01-01

    Type Ia supernovae (SNe) serve as a fundamental pillar of modern cosmology, owing to their large luminosity and a well-defined relationship between light-curve shape and peak brightness. The precision distance measurements enabled by SNe Ia first revealed the accelerating expansion of the universe, now widely believed (though hardly understood) to require the presence of a mysterious "dark" energy. General consensus holds that Type Ia SNe result from thermonuclear explosions of a white dwarf (WD) in a binary system; however, little is known of the precise nature of the companion star and the physical properties of the progenitor system. Here we make use of extensive historical imaging obtained at the location of SN 2011fe/PTF11kly, the closest SN Ia discovered in the digital imaging era, to constrain the visible-light luminosity of the progenitor to be 10-100 times fainter than previous limits on other SN Ia progenitors. This directly rules out luminous red giants and the vast majority of helium stars as the ...

  3. An outburst from a massive star 40 days before a supernova explosion.

    Science.gov (United States)

    Ofek, E O; Sullivan, M; Cenko, S B; Kasliwal, M M; Gal-Yam, A; Kulkarni, S R; Arcavi, I; Bildsten, L; Bloom, J S; Horesh, A; Howell, D A; Filippenko, A V; Laher, R; Murray, D; Nakar, E; Nugent, P E; Silverman, J M; Shaviv, N J; Surace, J; Yaron, O

    2013-02-07

    Some observations suggest that very massive stars experience extreme mass-loss episodes shortly before they explode as supernovae, as do several models. Establishing a causal connection between these mass-loss episodes and the final explosion would provide a novel way to study pre-supernova massive-star evolution. Here we report observations of a mass-loss event detected 40 days before the explosion of the type IIn supernova SN 2010mc (also known as PTF 10tel). Our photometric and spectroscopic data suggest that this event is a result of an energetic outburst, radiating at least 6 × 10(47) erg of energy and releasing about 10(-2) solar masses of material at typical velocities of 2,000 km s(-1). The temporal proximity of the mass-loss outburst and the supernova explosion implies a causal connection between them. Moreover, we find that the outburst luminosity and velocity are consistent with the predictions of the wave-driven pulsation model, and disfavour alternative suggestions.

  4. SN 2008S: A Cool Super-Eddington Wind in a Supernova Impostor

    CERN Document Server

    Smith, Nathan; Li, Weidong; Chornock, Ryan; Steele, Thea N; Silverman, Jeffrey M; Filippenko, Alexei V; Mobberley, Martin P

    2008-01-01

    We present visual-wavelength photometry and spectroscopy of SN2008S. Based on the relatively low peak luminosity for a supernova (SN) of M_R = -13.9 mag and moderate outflow speeds of \\la 600 km/s indicated by the spectrum, we find that SN2008S is not a true core-collapse SN or electron-capture SN. Instead, we interpret SN2008S as a "SN impostor" event much like SN1997bs, analogous to the giant eruptions of luminous blue variables. Its total radiated energy was ~10^47.8 ergs, and it may have ejected 0.05--0.2 Msun in the event. We note an uncanny similarity between the spectrum of SN2008S and that of the Galactic hypergiant IRC+10420, both of which are dominated by narrow H-alpha, [CaII], and CaII emission lines. We propose a scenario where the vastly super-Eddington (\\Gamma \\approx 40) wind of SN2008S partly fails because of a reduction in the electron-scattering opacity due to recombination. We favor a stellar mass of \\ga 20 Msun, and speculate that this outburst may have implications for the progenitor of ...

  5. SN 2010ay IS A LUMINOUS AND BROAD-LINED TYPE Ic SUPERNOVA WITHIN A LOW-METALLICITY HOST GALAXY

    Energy Technology Data Exchange (ETDEWEB)

    Sanders, N. E.; Soderberg, A. M.; Foley, R. J.; Chornock, R.; Chomiuk, L.; Berger, E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Valenti, S.; Smartt, S.; Botticella, M. T. [Astrophysics Research Centre, School of Maths and Physics, Queen' s University, Belfast BT7 1NN (United Kingdom); Hurley, K. [Space Sciences Laboratory, University of California Berkeley, 7 Gauss Way, Berkeley, CA 94720 (United States); Barthelmy, S. D.; Gehrels, N.; Cline, T. [NASA Goddard Space Flight Center, Code 661, Greenbelt, MD 20771 (United States); Levesque, E. M. [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Narayan, G. [Department of Physics, Harvard University, Cambridge, MA 02138 (United States); Briggs, M. S.; Connaughton, V. [CSPAR, University of Alabama in Huntsville, Huntsville, AL (United States); Terada, Y. [Department of Physics, Saitama University, Shimo-Okubo, Sakura-ku, Saitama-shi, Saitama 338-8570 (Japan); Golenetskii, S.; Mazets, E., E-mail: nsanders@cfa.harvard.edu [Ioffe Physico-Technical Institute, Laboratory for Experimental Astrophysics, 26 Polytekhnicheskaya, St. Petersburg 194021 (Russian Federation); and others

    2012-09-10

    We report on our serendipitous pre-discovery detection and follow-up observations of the broad-lined Type Ic supernova (SN Ic) 2010ay at z = 0.067 imaged by the Pan-STARRS1 3{pi} survey just {approx}4 days after explosion. The supernova (SN) had a peak luminosity, M{sub R} Almost-Equal-To -20.2 mag, significantly more luminous than known GRB-SNe and one of the most luminous SNe Ib/c ever discovered. The absorption velocity of SN 2010ay is v{sub Si} Almost-Equal-To 19 Multiplication-Sign 10{sup 3} km s{sup -1} at {approx}40 days after explosion, 2-5 times higher than other broad-lined SNe and similar to the GRB-SN 2010bh at comparable epochs. Moreover, the velocity declines {approx}2 times slower than other SNe Ic-BL and GRB-SNe. Assuming that the optical emission is powered by radioactive decay, the peak magnitude implies the synthesis of an unusually large mass of {sup 56}Ni, M{sub Ni} = 0.9 M{sub Sun }. Applying scaling relations to the light curve, we estimate a total ejecta mass, M{sub ej} Almost-Equal-To 4.7 M{sub Sun }, and total kinetic energy, E{sub K} Almost-Equal-To 11 Multiplication-Sign 10{sup 51} erg. The ratio of M{sub Ni} to M{sub ej} is {approx}2 times as large for SN 2010ay as typical GRB-SNe and may suggest an additional energy reservoir. The metallicity (log (O/H){sub PP04} + 12 = 8.19) of the explosion site within the host galaxy places SN 2010ay in the low-metallicity regime populated by GRB-SNe, and {approx}0.5(0.2) dex lower than that typically measured for the host environments of normal (broad-lined) SNe Ic. We constrain any gamma-ray emission with E{sub {gamma}} {approx}< 6 Multiplication-Sign 10{sup 48} erg (25-150 keV), and our deep radio follow-up observations with the Expanded Very Large Array rule out relativistic ejecta with energy E {approx}> 10{sup 48} erg. We therefore rule out the association of a relativistic outflow like those that accompanied SN 1998bw and traditional long-duration gamma-ray bursts (GRBs), but we place less

  6. SN 2004A: Another Type II-P Supernova with a Red Supergiant Progenitor

    CERN Document Server

    Hendry, M A; Cenko, S B; Crockett, R M; Fox, D W; Gal-Yam, A; Kudritzki, R P; Maund, J R; Moon, D S; Smartt, S J

    2006-01-01

    We present a monitoring study of SN 2004A and probable discovery of a progenitor star in pre-explosion HST images. The photometric and spectroscopic monitoring of SN 2004A show that it was a normal Type II-P which was discovered in NGC 6207 about two weeks after explosion. We compare SN 2004A to the similar Type II-P SN 1999em and estimate an explosion epoch of 2004 January 6. We also calculate three new distances to NGC 6207 of 21.0 +/-4.3, 21.4 +/-3.5 and 25.1 +/-1.7Mpc. The former was calculated using the Standard Candle Method (SCM) for SNe II-P, and the latter two from the Brightest Supergiants Method (BSM). We combine these three distances with existing kinematic distances, to derive a mean value of 20.3 +/-3.4Mpc. Using this distance we estimate that the ejected nickel mass in the explosion is 0.046(+0.031,-0.017) Msolar. The progenitor of SN 2004A is identified in pre-explosion WFPC2 F814W images with a magnitude of mF814W = 24.3 +/-0.3, but is below the detection limit of the F606W images. We show th...

  7. An Emerging Coherent Picture of Red Supergiant Supernova Explosions

    OpenAIRE

    Poznanski, Dovi

    2013-01-01

    Three lines of evidence indicate that in the most common type of core collapse supernovae, the energy deposited in the ejecta by the exploding core is approximately proportional to the progenitor mass cubed. This results stems from an observed uniformity of light curve plateau duration, a correlation between mass and ejecta velocity, and the known correlation between luminosity and velocity. This result ties in analytical and numerical models together with observations, providing us with clue...

  8. Slowly fading super-luminous supernovae that are not pair-instability explosions

    Science.gov (United States)

    Nicholl, M.; Smartt, S. J.; Jerkstrand, A.; Inserra, C.; McCrum, M.; Kotak, R.; Fraser, M.; Wright, D.; Chen, T.-W.; Smith, K.; Young, D. R.; Sim, S. A.; Valenti, S.; Howell, D. A.; Bresolin, F.; Kudritzki, R. P.; Tonry, J. L.; Huber, M. E.; Rest, A.; Pastorello, A.; Tomasella, L.; Cappellaro, E.; Benetti, S.; Mattila, S.; Kankare, E.; Kangas, T.; Leloudas, G.; Sollerman, J.; Taddia, F.; Berger, E.; Chornock, R.; Narayan, G.; Stubbs, C. W.; Foley, R. J.; Lunnan, R.; Soderberg, A.; Sanders, N.; Milisavljevic, D.; Margutti, R.; Kirshner, R. P.; Elias-Rosa, N.; Morales-Garoffolo, A.; Taubenberger, S.; Botticella, M. T.; Gezari, S.; Urata, Y.; Rodney, S.; Riess, A. G.; Scolnic, D.; Wood-Vasey, W. M.; Burgett, W. S.; Chambers, K.; Flewelling, H. A.; Magnier, E. A.; Kaiser, N.; Metcalfe, N.; Morgan, J.; Price, P. A.; Sweeney, W.; Waters, C.

    2013-10-01

    Super-luminous supernovae that radiate more than 1044 ergs per second at their peak luminosity have recently been discovered in faint galaxies at redshifts of 0.1-4. Some evolve slowly, resembling models of `pair-instability' supernovae. Such models involve stars with original masses 140-260 times that of the Sun that now have carbon-oxygen cores of 65-130 solar masses. In these stars, the photons that prevent gravitational collapse are converted to electron-positron pairs, causing rapid contraction and thermonuclear explosions. Many solar masses of 56Ni are synthesized; this isotope decays to 56Fe via 56Co, powering bright light curves. Such massive progenitors are expected to have formed from metal-poor gas in the early Universe. Recently, supernova 2007bi in a galaxy at redshift 0.127 (about 12 billion years after the Big Bang) with a metallicity one-third that of the Sun was observed to look like a fading pair-instability supernova. Here we report observations of two slow-to-fade super-luminous supernovae that show relatively fast rise times and blue colours, which are incompatible with pair-instability models. Their late-time light-curve and spectral similarities to supernova 2007bi call the nature of that event into question. Our early spectra closely resemble typical fast-declining super-luminous supernovae, which are not powered by radioactivity. Modelling our observations with 10-16 solar masses of magnetar-energized ejecta demonstrates the possibility of a common explosion mechanism. The lack of unambiguous nearby pair-instability events suggests that their local rate of occurrence is less than 6 × 10-6 times that of the core-collapse rate.

  9. Slowly fading super-luminous supernovae that are not pair-instability explosions.

    Science.gov (United States)

    Nicholl, M; Smartt, S J; Jerkstrand, A; Inserra, C; McCrum, M; Kotak, R; Fraser, M; Wright, D; Chen, T-W; Smith, K; Young, D R; Sim, S A; Valenti, S; Howell, D A; Bresolin, F; Kudritzki, R P; Tonry, J L; Huber, M E; Rest, A; Pastorello, A; Tomasella, L; Cappellaro, E; Benetti, S; Mattila, S; Kankare, E; Kangas, T; Leloudas, G; Sollerman, J; Taddia, F; Berger, E; Chornock, R; Narayan, G; Stubbs, C W; Foley, R J; Lunnan, R; Soderberg, A; Sanders, N; Milisavljevic, D; Margutti, R; Kirshner, R P; Elias-Rosa, N; Morales-Garoffolo, A; Taubenberger, S; Botticella, M T; Gezari, S; Urata, Y; Rodney, S; Riess, A G; Scolnic, D; Wood-Vasey, W M; Burgett, W S; Chambers, K; Flewelling, H A; Magnier, E A; Kaiser, N; Metcalfe, N; Morgan, J; Price, P A; Sweeney, W; Waters, C

    2013-10-17

    Super-luminous supernovae that radiate more than 10(44) ergs per second at their peak luminosity have recently been discovered in faint galaxies at redshifts of 0.1-4. Some evolve slowly, resembling models of 'pair-instability' supernovae. Such models involve stars with original masses 140-260 times that of the Sun that now have carbon-oxygen cores of 65-130 solar masses. In these stars, the photons that prevent gravitational collapse are converted to electron-positron pairs, causing rapid contraction and thermonuclear explosions. Many solar masses of (56)Ni are synthesized; this isotope decays to (56)Fe via (56)Co, powering bright light curves. Such massive progenitors are expected to have formed from metal-poor gas in the early Universe. Recently, supernova 2007bi in a galaxy at redshift 0.127 (about 12 billion years after the Big Bang) with a metallicity one-third that of the Sun was observed to look like a fading pair-instability supernova. Here we report observations of two slow-to-fade super-luminous supernovae that show relatively fast rise times and blue colours, which are incompatible with pair-instability models. Their late-time light-curve and spectral similarities to supernova 2007bi call the nature of that event into question. Our early spectra closely resemble typical fast-declining super-luminous supernovae, which are not powered by radioactivity. Modelling our observations with 10-16 solar masses of magnetar-energized ejecta demonstrates the possibility of a common explosion mechanism. The lack of unambiguous nearby pair-instability events suggests that their local rate of occurrence is less than 6 × 10(-6) times that of the core-collapse rate.

  10. The Young Massive Stellar Cluster Sandage-96 after the Explosion of SN 2004DJ in NGC 2403

    Science.gov (United States)

    Vinko, J.; Sarneczky, K.; Balog, Z.; Immler, S.; Sugerman, B.; Brown, P. J.; Misselt, K.; Szabo, Gy. M.; Klagyivik, P.; Kun, M.; Foley R.; Filippenko, A. V.; Csak, B.; Kiss, L. L.

    2008-01-01

    The bright supernova 2004dj occurred within the young massive stellar cluster Sandage-96 in a spiral arm of NGC 2403, close to other star-forming complexes. New multi-wavelength observations obtained with several ground-based- and space telescopes are combined to study the radiation from Sandage-96 after SN 2004dj faded away. The late-time light curves show that Sandage-96 started to dominate the flux in the optical bands after September, 2006 (+800 days after explosion). The optical fluxes are equal to the pre-explosion ones, suggesting that Sandage-96 has survived the explosion without significant changes in its stellar population. An optical Keck-spectrum obtained at +900 days after explosion shows the dominant blue continuum from the cluster stars shortward of 6000 A as well as strong SN nebular emission lines redward. The integrated SED of the cluster has been extended into the UV-region by archival XMM-Newton and new Swift observations, and compared with theoretical models. The outer parts of the cluster have been resolved by HST allowing the construction of a color-magnitude diagram. The fitting of the cluster SED with theoretical isochrones results in two possible solutions with ages being 9+/-1 Myr and 30+/-10 Myr, depending on the assumed metallicity and the theoretical model family. The isochrone fitting of the color-magnitude diagram indicates that the outer part of the cluster consists of stars having an age dispersion of 16 explosion SEDs suggest a progenitor mass of 15 < or equal to M(sub prog) < 25 Stellar Mass.

  11. Evolution, Explosion and Nucleosynthesis of Core Collapse Supernovae

    CERN Document Server

    Limongi, M

    2003-01-01

    We present a new set of presupernova evolutions and explosive yields of massive stars of initial solar composition (Y=0.285, Z=0.02) in the mass range 13-35 Msun. All the models have been computed with the latest version (4.97) of the FRANEC code that now includes a nuclear network extending from neutrons to Mo98. The explosive nucleosynthesis has been computed twice: a first one with an hydro code and a second one following the simpler radiation dominated shock approximation (RDA).

  12. Extreme explosions supernovae, hypernovae, magnetars, and other unusual cosmic blasts

    CERN Document Server

    Stevenson, David S

    2013-01-01

    What happens at the end of the life of massive stars? At one time we thought all these stars followed similar evolutionary paths. However, new discoveries have shown that things are not quite that simple. This book focuses on the extreme -the most intense, brilliant and peculiar- of astronomical explosions. It features highly significant observational finds that push the frontiers of astronomy and astrophysics, particularly as before these objects were only predicted in theory.  This book is for those who want the latest information and ideas about the most dramatic and unusual explosions dete

  13. SN 2009E: a faint clone of SN 1987A

    DEFF Research Database (Denmark)

    Pastorello, A.; Pumo, M. L.; Navasardyan, H.

    2012-01-01

    Context.1987A-like events form a rare sub-group of hydrogen-rich core-collapse supernovae that are thought to originate from the explosion of blue supergiant stars. Although SN 1987A is the best known supernova, very few objects of this group have been discovered and, hence, studied. Aims. In thi...

  14. 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.

  15. The Crab nebula and the class of Type IIn-P supernovae caused by sub-energetic electron-capture explosions

    Science.gov (United States)

    Smith, Nathan

    2013-09-01

    What sort of supernova (SN) gave rise to the Crab nebula? While there are several indications that the Crab arose from a sub-energetic explosion of an 8-10 M⊙ progenitor star, this would appear to conflict with the high luminosity indicated by historical observations. This paper shows that several well-known observed properties of the Crab and SN 1054 are well matched by a particular breed of Type IIn SN. The Crab's properties are best suited to the Type IIn-P subclass (Type IIn spectra with plateau light curves), exemplified by SNe 1994W, 2009kn and 2011ht. These events probably arise from relatively low energy (1050 erg) explosions with low 56Ni yield that may result from electron-capture SN (ecSN) explosions, but their high visual-wavelength luminosity and Type IIn spectra are dominated by shock interaction with dense circumstellar material (CSM) rather than the usual recombination photosphere. In this interaction, a large fraction of the 1050 erg of the total kinetic energy can be converted to visual-wavelength luminosity. After about 120 d, nearly all of the mass outside the neutron star in the CSM and ejecta ends up in a slowly expanding (1000-1500 km s-1) thin dense shell, which is then accelerated and fragmented by the growing pulsar wind nebula in the subsequent 1000 yr, producing the complex network of filaments seen today. There is no need to invoke the extended, invisible fast SN envelope hypothesized to reside outside the Crab. As differentiated from a normal SN II-P, SNe IIn-P provide a much better explanation for several observed features of the Crab: (1) no blast wave outside the Crab nebula filaments, (2) no rapidly expanding SN envelope outside the filaments, (3) a total mass of ˜5 M⊙ swept up in a thin slow shell, (4) a low kinetic energy of the Crab at least an order of magnitude below a normal core-collapse SN, (5) a high peak luminosity (-18 mag) despite the low kinetic energy, (6) chemical abundances consistent with an 8-10 M⊙ star and

  16. Spectroscopic Classification of SN 2017ghm as a Type Ia Supernova

    Science.gov (United States)

    Vinko, J.; Wheeler, J. C.; Wang, X.; Li, W.; Li, Z.; Xiang, D.; Rui, L.; Lin, H.; Xu, Z.; Li, B.; Zhao, H.; Wang, L.; Tan, H.; Zhang, J.

    2017-09-01

    An optical spectrum (range 360-680 nm) of SN 2017ghm (=PTSS-17uyml), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), was obtained with the new "Low Resolution Spectrograph-2" (LRS2) on the 10m Hobby-Eberly Telescope at McDonald Observatory by S. Rostopchin on 2017 Aug 31.17 UT. The spectrum is consistent with that of a heavily reddened Type Ia supernova (with Av > 2.3 mag) around maximum light.

  17. Impact of New Gamow-Teller Strengths on Explosive Type Ia Supernova Nucleosynthesis

    CERN Document Server

    Mori, Kanji; Kajino, Toshitaka; Suzuki, Toshio; Hidaka, Jun; Honma, Michio; Iwamoto, Koichi; Nomoto, Ken'ichi; Otsuka, Takaharu

    2016-01-01

    Recent experimental results have confirmed a possible reduction in the GT$_+$ strengths of pf-shell nuclei. These proton-rich nuclei are of relevance in the deflagration and explosive burning phases of Type Ia supernovae. While prior GT strengths result in nucleosynthesis predictions with a lower-than-expected electron fraction, a reduction in the GT$_+$ strength can result in an slightly increased electron fraction compared to previous shell model predictions, though the enhancement is not as large as previous enhancements in going from rates computed by Fuller, Fowler, and Newman based on an independent particle model. A shell model parametrization has been developed which more closely matches experimental GT strengths. The resultant electron-capture rates are used in nucleosynthesis calculations for carbon deflagration and explosion phases of Type Ia supernovae, and the final mass fractions are compared to those obtained using more commonly-used rates.

  18. R-Process Nucleosynthesis in MHD Jet Explosions of Core-Collapse Supernovae

    Directory of Open Access Journals (Sweden)

    Motoaki Saruwatari

    2013-01-01

    Full Text Available We investigate the r-process nucleosynthesis during the magnetohydrodynamical (MHD explosion of a supernova in a helium star of 3.3 M⊙, where effects of neutrinos are taken into account using the leakage scheme in the two-dimensional (2D hydrodynamic code. Jet-like explosion due to the combined effects of differential rotation and magnetic field is able to erode the lower electron fraction matter from the inner layers. We find that the ejected material of low electron fraction responsible for the r-process comes out from just outside the neutrino sphere deep inside the Fe-core. It is found that heavy element nucleosynthesis depends on the initial conditions of rotational and magnetic fields. In particular, the third peak of the distribution is significantly overproduced relative to the solar system abundances, which would indicate a possible r-process site owing to MHD jets in supernovae.

  19. Three-dimensional Explosion Geometry of Stripped-envelope Core-collapse Supernovae. II. Modeling of Polarization

    Science.gov (United States)

    Tanaka, Masaomi; Maeda, Keiichi; Mazzali, Paolo A.; Kawabata, Koji S.; Nomoto, Ken’ichi

    2017-03-01

    We present modeling of line polarization to study the multidimensional geometry of stripped-envelope core-collapse supernovae (SNe). We demonstrate that a purely axisymmetric, two-dimensional (2D) geometry cannot reproduce a loop in the Stokes Q ‑ U diagram, that is, a variation of the polarization angles along the velocities associated with the absorption lines. On the contrary, three-dimensional (3D) clumpy structures naturally reproduce the loop. The fact that the loop is commonly observed in stripped-envelope SNe suggests that SN ejecta generally have a 3D structure. We study the degree of line polarization as a function of the absorption depth for various 3D clumpy models with different clump sizes and covering factors. A comparison between the calculated and observed degree of line polarization indicates that a typical size of the clump is relatively large, ≳25% of the photospheric radius. Such large-scale clumps are similar to those observed in the SN remnant Cassiopeia A. Given the small size of the observed sample, the covering factor of the clumps is only weakly constrained (∼5%–80%). The presence of a large-scale clumpy structure suggests that the large-scale convection or standing accretion shock instability takes place at the onset of the explosion.

  20. Metamorphosis of SN 2014C: Delayed Interaction Between a Hydrogen Poor Core-collapse Supernova and a Nearby Circumstellar Shell

    CERN Document Server

    Milisavljevic, D; Kamble, A; Patnaude, D; Raymond, J; Eldridge, J; Fong, W; Bietenholz, M; Challis, P; Chornock, R; Drout, M; Fransson, C; Fesen, R; Grindlay, J; Kirshner, R; Lunnan, R; Mackey, J; Miller, G; Parrent, J; Sanders, N; Soderberg, A; Zauderer, B

    2015-01-01

    We present optical observations of supernova SN 2014C, which underwent an unprecedented slow metamorphosis from H-poor type Ib to H-rich type IIn over the course of one year. The observed spectroscopic evolution is consistent with the supernova having exploded in a cavity before encountering a massive shell of the progenitor star's stripped hydrogen envelope. Possible origins for the circumstellar shell include a brief Wolf-Rayet fast wind phase that overtook a slower red supergiant wind, eruptive ejection, or confinement of circumstellar material by external influences of neighboring stars. An extended high velocity Halpha absorption feature seen in near-maximum light spectra implies that the progenitor star was not completely stripped of hydrogen at the time of core collapse. Archival pre-explosion Subaru Telescope Suprime-Cam and Hubble Space Telescope Wide Field Planetary Camera 2 images of the region obtained in 2009 show a coincident source that is most likely a compact massive star cluster in NGC 7331 ...

  1. A Spitzer Space Telescope Study of SN 2003gd: Still No Direct Evidence that Core-Collapse Supernovae are Major Dust Factories

    CERN Document Server

    Meikle, W P S; Pastorello, A; Gerardy, C L; Kotak, R; Sollerman, J; Van Dyk, S D; Farrah, D; Filippenko, A V; Höflich, P; Lundqvist, P; Pozzo, M; Wheeler, J C

    2007-01-01

    We present a new, detailed analysis of late-time mid-infrared (IR) observations of the Type II-P supernova (SN) 2003gd. At about 16 months after the explosion, the mid-IR flux is consistent with emission from 4 x 10^(-5) M(solar) of newly condensed dust in the ejecta. At 22 months emission from point-like sources close to the SN position was detected at 8 microns and 24 microns. By 42 months the 24 micron flux had faded. Considerations of luminosity and source size rule out the ejecta of SN 2003gd as the main origin of the emission at 22 months. A possible alternative explanation for the emission at this later epoch is an IR echo from pre-existing circumstellar or interstellar dust. We conclude that, contrary to the claim of Sugerman et al. (2006, Science, 313, 196), the mid-IR emission from SN 2003gd does not support the presence of 0.02 M(solar) of newly formed dust in the ejecta. There is, as yet, no direct evidence that core-collapse supernovae are major dust factories.

  2. 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.

  3. Type Iax Supernovae: A New Class of Stellar Explosion

    DEFF Research Database (Denmark)

    Foley, Ryan J.; Challis, P. J.; Chornock, R.

    2013-01-01

    are spectroscopically similar to SNe Ia, but have lower maximum-light velocities (2000 M_V,peak > -18.9 mag), and most have hot photospheres. Relative to SNe Ia, SNe Iax have low luminosities for their light-curve shape. There is a correlation between...... luminosity and light-curve shape, similar to that of SNe Ia, but offset from that of SNe Ia and with larger scatter. Despite a host-galaxy morphology distribution that is highly skewed to late-type galaxies without any SNe Iax discovered in elliptical galaxies, there are several indications...... in their spectra. The progenitor system and explosion model that best fits all of the data is a binary system of a C/O WD that accretes matter from a He star and has a significant deflagration. At least some of the time, this explosion will not disrupt the WD. We estimate that in a given volume there are 31^+17...

  4. Accelerating Our Understanding of Supernova Explosion Mechanism via Simulations and Visualizations with GenASiS

    Energy Technology Data Exchange (ETDEWEB)

    Budiardja, R. D. [University of Tennessee, Knoxville (UTK); Cardall, Christian Y [ORNL; Endeve, Eirik [ORNL

    2015-01-01

    Core-collapse supernovae are among the most powerful explosions in the Universe, releasing about 1053 erg of energy on timescales of a few tens of seconds. These explosion events are also responsible for the production and dissemination of most of the heavy elements, making life as we know it possible. Yet exactly how they work is still unresolved. One reason for this is the sheer complexity and cost of a self-consistent, multi-physics, and multi-dimensional core-collapse supernova simulation, which is impractical, and often impossible, even on the largest supercomputers we have available today. To advance our understanding we instead must often use simplified models, teasing out the most important ingredients for successful explosions, while helping us to interpret results from higher fidelity multi-physics models. In this paper we investigate the role of instabilities in the core-collapse supernova environment. We present here simulation and visualization results produced by our code GenASiS.

  5. Accelerating Our Understanding of Supernova Explosion Mechanism via Simulations and Visualizations with GenASiS

    CERN Document Server

    Budiardja, Reuben D; Endeve, Eirik

    2015-01-01

    Core-collapse supernovae are among the most powerful explosions in the Universe, releasing about $10^{53}~\\mbox{erg}$ of energy on timescales of a few tens of seconds. These explosion events are also responsible for the production and dissemination of most of the heavy elements, making life as we know it possible. Yet exactly how they work is still unresolved. One reason for this is the sheer complexity and cost of a self-consistent, multi-physics, and multi-dimensional core-collapse supernova simulation, which is impractical, and often impossible, even on the largest supercomputers we have available today. To advance our understanding we instead must often use simplified models, teasing out the most important ingredients for successful explosions, while helping us to interpret results from higher fidelity multi-physics models. In this paper we investigate the role of instabilities in the core-collapse supernova environment. We present here simulation and visualization results produced by our code GenASiS.

  6. On type IIn/Ia-CSM supernovae as exemplified by SN 2012ca

    CERN Document Server

    Inserra, C; Smartt, S J; Benetti, S; Chen, T -W; Childress, M; Gal-Yam, A; Howell, D A; Kangas, T; Pignata, G; Polshaw, J; Sullivan, M; Smith, K W; Valenti, S; Young, D R; Parker, S; Seccull, T; McCrum, M

    2015-01-01

    We present the complete set of ultra-violet, optical and near-infrared photometry and spectroscopy for SN 2012ca, covering the period from 6 days prior to maximum light, until 531 days after maximum. The spectroscopic time series for SN 2012ca is essentially unchanged over 1.5 years, and appear to be dominated at all epochs by signatures of interaction with a dense circumstellar medium rather than the underlying supernova (SN). SN 2012ca is a member of the class of type Ia-CSM/IIn SNe, the nature of which have been debated extensively in the literature. The two leading scenarios are either a type Ia SN exploding within a dense CSM from a non-degenerate, evolved companion, or a core-collapse SN from a massive star. While some members of the class have been unequivocally associated with type Ia SNe, in other cases the association is less certain. While it is possible that Sn 2012ca does arise from a thermonuclear SN, this would require a relatively high (between 20 and 70 per cent) efficiency in converting kine...

  7. Pre-Explosive Observational Properties of Type Ia Supernovae

    CERN Document Server

    Tornambé, A; 10.1093/mnras/stt295

    2013-01-01

    The evolutionary path of rotating CO WDs directly accreting CO-rich matter is followed up to few seconds before the explosive breakout in the framework of the Double Degenerate rotationally-driven accretion scenario. We find that the evolutionary properties depend only on the actual mass of the accreting WD and not on the previous history. We determine the expected frequency and amplitude of the gravitational wave emission, which occurs during the mass transfer process and acts as a self-tuning mechanism of the accretion process itself. The gravitational signal related to Galactic sources can be easily detected with the next generation of space-born interferometers and can provide notable constraints to the progenitor model. The expected statistical distribution of pre-explosive objects in the Galaxy is provided also in the effective temperature-apparent bolometric magnitude diagrams which can be used to identify merged DD systems via UV surveys. We emphasize that the thermonuclear explosion occurs owing to t...

  8. SN 2015bh: NGC 2770's 4th supernova or a luminous blue variable on its way to a Wolf-Rayet star?

    CERN Document Server

    Thöne, C C; Leloudas, G; Gall, C; Cano, Z; Maeda, K; Schulze, S; Campana, S; Wiersema, K; Groh, J; de la Rosa, J; Bauer, F E; Malesani, D; Maund, J; Morrell, N; Beletsky, Y

    2016-01-01

    Very massive stars in the final phases of their lives often show unpredictable outbursts that can mimic supernovae, so-called, "SN impostors", but the distinction is not always straigthforward. Here we present observations of a luminous blue variable (LBV) in NGC 2770 in outburst over more than 20 years that experienced a possible terminal explosion as type IIn SN in 2015, named SN 2015bh. This possible SN or "main event" was preceded by a precursor peaking $\\sim$ 40 days before maximum. The total energy release of the main event is $\\sim$1.8$\\times$10$^{49}$ erg, which can be modeled by a $<$ 0.5 M$_\\odot$ shell plunging into a dense CSM. All emission lines show a single narrow P-Cygni profile during the LBV phase and a double P-Cygni profile post maximum suggesting an association of this second component with the possible SN. Since 1994 the star has been redder than during a typical S-Dor like outburst. SN 2015bh lies within a spiral arm of NGC 2770 next to a number of small star-forming regions with a m...

  9. 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.

  10. 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).

  11. Recent Progress on Ascertaining the Core Collapse Supernova Explosion Mechanism

    CERN Document Server

    Mezzacappa, Anthony; Lentz, Eric J; Hix, W Raphael; Harris, J Austin; Messer, O E Bronson; Endeve, Eirik; Chertkow, Merek A; Blondin, John M; Marronetti, Pedro; Yakunin, Konstantin N

    2015-01-01

    We have been working within the fundamental paradigm that core collapse supernovae (CCSNe) may be neutrino driven, since the first suggestion of this by Colgate and White nearly five decades ago. Computational models have become increasingly sophisticated, first in one spatial dimension assuming spherical symmetry, then in two spatial dimensions assuming axisymmetry, and now in three spatial dimensions with no imposed symmetries. The increase in the number of spatial dimensions has been accompanied by an increase in the physics included in the models, and an increase in the sophistication with which this physics has been modeled. Computation has played an essential role in the development of CCSN theory, not simply for the obvious reason that such multidimensional, multi-physics, nonlinear events cannot possibly be fully captured analytically, but for its role in discovery. In particular, the discovery of the standing accretion shock instability (SASI) through computation about a decade ago has impacted all s...

  12. Slowly fading super-luminous supernovae that are not pair-instability explosions

    CERN Document Server

    Nicholl, M; Jerkstrand, A; Inserra, C; McCrum, M; Kotak, R; Fraser, M; Wright, D; Chen, T -W; Smith, K; Young, D R; Sim, S A; Valenti, S; Howell, D A; Bresolin, F; Kudritzki, R P; Tonry, J L; Huber, M E; Rest, A; Pastorello, A; Tomasella, L; Cappellaro, E; Benetti, S; Mattila, S; Kankare, E; Kangas, T; Leloudas, G; Sollerman, J; Taddia, F; Berger, E; Chornock, R; Narayan, G; Stubbs, C W; Foley, R J; Lunnan, R; Soderberg, A; Sanders, N; Milisavljevic, D; Margutti, R; Kirshner, R P; Elias-Rosa, N; Morales-Garoffolo, A; Taubenberger, S; Botticella, M T; Gezari, S; Urata, Y; Rodney, S; Riess, A G; Scolnic, D; Wood-Vasey, W M; Burgett, W S; Chambers, K; Flewelling, H A; Magnier, E A; Kaiser, N; Metcalfe, N; Morgan, J; Price, P A; Sweeney, W; Waters, C

    2013-01-01

    Super-luminous supernovae that radiate more than 10^44 ergs per second at their peak luminosity have recently been discovered in faint galaxies at redshifts of 0.1-4. Some evolve slowly, resembling models of 'pair-instability' supernovae. Such models involve stars with original masses 140-260 times that of the Sun that now have carbon-oxygen cores of 65-30 solar masses. In these stars, the photons that prevent gravitational collapse are converted to electron-positron pairs, causing rapid contraction and thermonuclear explosions. Many solar masses of 56Ni are synthesized; this isotope decays to 56Fe via 56Co, powering bright light curves. Such massive progenitors are expected to have formed from metal-poor gas in the early Universe. Recently, supernova 2007bi in a galaxy at redshift 0.127 (about 12 billion years after the Big Bang) with a metallicity one-third that of the Sun was observed to look like a fading pair-instability supernova. Here we report observations of two slow-to-fade super-luminous supernovae...

  13. Constraining the Progenitor of the Type Ia Supernova SN 2012cg

    CERN Document Server

    Liu, Zheng-Wei

    2016-01-01

    The nature of the progenitors of SNe Ia is not yet fully understood. In the single-degenerate (SD) scenario, the collision of the SN ejecta with its companion star is expected to produce detectable UV emission in the first few days after the SN explosion within certain viewing angles. It was recently found that the $B-V$ colour of the nearby SN Ia SN 2012cg at about sixteen days before the maximum $B$-band brightness was about 0.2 mag bluer than those of other normal SNe Ia, which was reported as the first evidence for excess blue light from the interaction of normal SN Ia ejecta with its companion star. In this work, we compare current observations for SN 2012cg from its pre-explosion phase to the late-time nebular phase with theoretical predictions from binary evolution and population synthesis calculations for a variety of popular progenitor scenarios. We find that a main-sequence donor or a carbon-oxygen white dwarf donor binary system is more likely to be the progenitor of SN 2012cg. However, both scenar...

  14. Neutrino Signal of Collapse-Induced Thermonuclear Supernovae: The Case for Prompt Black Hole Formation in SN1987A

    CERN Document Server

    Blum, Kfir

    2016-01-01

    Collapse-induced thermonuclear explosion (CITE) may explain core-collapse supernovae (CCSNe). We present a preliminary analysis of the neutrino signal predicted by CITE and compare it to the neutrino burst of SN1987A. For strong CCSNe, as SN1987A, CITE predicts a proto-neutron star (PNS) accretion phase, accompanied by the corresponding neutrino luminosity, that can last a few seconds and that is cut-off abruptly by black hole (BH) formation. The neutrino luminosity can later be revived by accretion disc emission after a dead time of few to a few ten seconds. In contrast, the neutrino mechanism for CCSNe predicts a shorter PNS accretion phase, followed by a slowly declining PNS cooling luminosity. We repeat statistical analyses used in the literature to interpret the neutrino mechanism, and apply them to CITE. The first 1-2 sec of the neutrino burst are equally compatible with CITE and with the neutrino mechanism. However, the data hints to a luminosity drop at t=2-3 sec, in some tension with the neutrino mec...

  15. A trio of gamma-ray burst supernovae:. GRB 120729A, GRB 130215A/SN 2013ez, and GRB 130831A/SN 2013fu

    NARCIS (Netherlands)

    Cano, Z.; et al., [Unknown; Hartoog, O.

    2014-01-01

    We present optical and near-infrared (NIR) photometry for three gamma-ray burst supernovae (GRB-SNe): GRB 120729A, GRB 130215A/SN 2013ez, and GRB 130831A/SN 2013fu. For GRB 130215A/SN 2013ez, we also present optical spectroscopy at t − t0 = 16.1 d, which covers rest-frame 3000-6250 Å. Based on Fe ii

  16. Inferring the core-collapse supernova explosion mechanism with gravitational waves

    Science.gov (United States)

    Powell, Jade; Gossan, Sarah E.; Logue, Joshua; Heng, Ik Siong

    2016-12-01

    A detection of a core-collapse supernova (CCSN) gravitational-wave (GW) signal with an Advanced LIGO and Virgo detector network may allow us to measure astrophysical parameters of the dying massive star. GWs are emitted from deep inside the core, and, as such, they are direct probes of the CCSN explosion mechanism. In this study, we show how we can determine the CCSN explosion mechanism from a GW supernova detection using a combination of principal component analysis and Bayesian model selection. We use simulations of GW signals from CCSN exploding via neutrino-driven convection and rapidly rotating core collapse. Previous studies have shown that the explosion mechanism can be determined using one LIGO detector and simulated Gaussian noise. As real GW detector noise is both nonstationary and non-Gaussian, we use real detector noise from a network of detectors with a sensitivity altered to match the advanced detectors design sensitivity. For the first time, we carry out a careful selection of the number of principal components to enhance our model selection capabilities. We show that with an advanced detector network we can determine if the CCSN explosion mechanism is driven by neutrino convection for sources in our Galaxy and rapidly-rotating core collapse for sources out to the Large Magellanic Cloud.

  17. Early observations of the nearby type Ia supernova SN 2015F

    CERN Document Server

    Cartier, R; Firth, R; Pignata, G; Mazzali, P; Maguire, K; Childress, M J; Arcavi, I; Ashall, C; Frohmaier, C; Galbany, L; Gal-Yam, A; Hosseinzadeh, G; Howell, D A; Johansson, J; McCully, C; Prajs, S; Prentice, S; Schulze, S; Smartt, S J; Smith, K W; Smith, M; Valenti, S; Young, D R

    2016-01-01

    We present photometry and time-series spectroscopy of the nearby type Ia supernova (SN Ia) SN 2015F over $-16$ days to $+80$ days relative to maximum light, obtained as part of the Public ESO Spectroscopic Survey of Transient Objects (PESSTO). SN 2015F is a slightly sub-luminous SN Ia with a decline rate of $\\Delta m15(B)=1.35 \\pm 0.03$ mag, placing it in the region between normal and SN 1991bg-like events. Our densely-sampled photometric data place tight constraints on the epoch of first light and form of the early-time light curve. The spectra exhibit photospheric C II $\\lambda 6580$ absorption until $-4$ days, and high-velocity Ca II is particularly strong at $14000$ km s$^{-1}$, suggesting mixing in the outermost layers of the SN ejecta. Although unusual in SN Ia spectra, including V II in the modelling significantly improves the spectral fits. Intriguingly, we detect an absorption feature at $\\sim$6800 \\AA\\ that persists until maximum light. Our favoured explanation for this line is photospheric Al II, w...

  18. Hot third family of compact stars and the possibility of core-collapse supernova explosions

    Science.gov (United States)

    Hempel, Matthias; Heinimann, Oliver; Yudin, Andrey; Iosilevskiy, Igor; Liebendörfer, Matthias; Thielemann, Friedrich-Karl

    2016-11-01

    A phase transition to quark matter can lead to interesting phenomenological consequences in core-collapse supernovae, e.g., triggering an explosion in spherically symmetric models. However, until now, this explosion mechanism was only shown to be working for equations of state that are in contradiction with recent pulsar mass measurements. Here, we identify that this explosion mechanism is related to the existence of a third family of compact stars. For the equations of state investigated, the third family is only pronounced in the hot, early stages of the protocompact star and absent or negligibly small at zero temperature and thus represents a novel kind of third family. This interesting behavior is a result of unusual thermal properties induced by the phase transition, e.g., characterized by a decrease of temperature with increasing density for isentropes, and can be related to a negative slope of the phase transition line in the temperature-pressure phase diagram.

  19. SN 2014cx: A case study of a normal type II-plateau supernova

    Science.gov (United States)

    Flatland, Kelsi O'Leary

    Type II-plateau supernovae (SNe II-P) are characterized by hydrogen in the spectrum and an enduring period of nearly constant optical brightness, likely due to the progenitors having large, intact hydrogen envelopes (i.e. red supergiants). SNe II-P are the most commonly observed core-collapse event, and yet the basic characteristics of this class are still being defined. We add to the growing sample of II-P SNe with well-sampled observations of SN 2014cx. It was discovered on September 2, 2014 UT in the SBd galaxy NGC 337, which has a Tully-Fisher distance of 20.7 1.7 Mpc. SN 2014cx was classified as type II through spectra taken within a day of discovery, and later as II-P based on an initial photometric analysis. We initiated a photometric and spectropolarimetric campaign to follow SN 2014cx; over a five-month period, we obtained optical BVRcIc images using Mount Laguna Observatorys 40-inch telescope as part of the MOunt LAguna SUpernova Survey (MOLASUS) and spectropolarimetry as part of the SuperNova SpectroPOLarimetry project (SNSPOL). Here I present an analysis of the photometry and spectroscopy obtained during this campaign. From the photometric light- and color-curves, I establish the II-P classification, measuring a plateau decline-rate in V to be 0.0039 0.0005 mag/day, within normal bounds for SNe II-P. To better investigate the photometric behavior, I employ several techniques to establish that SN 2014cx's light suffers little to no host-galaxy extinction. I demonstrate that SN 2014cx's light- and color-curves exhibit shapes typical of SNe II-P, aside from minor peculiarities. From the spectropolarimetry, I analyze the extremely high signal-to-noise flux spectra. Using the FeII 5169 absorption feature, I find that the photospheric velocity shows temporal evolution typical of SNe II-P: declining steadily during the plateau as the photosphere recedes. Finally, I apply the the standardized candle method and determine a distance to SN 2014cx of 21.0 1.7 Mpc

  20. OISTER optical and near-infrared observations of the super-Chandrasekhar supernova candidate SN 2012dn: Dust emission from the circumstellar shell

    Science.gov (United States)

    Yamanaka, Masayuki; Maeda, Keiichi; Tanaka, Masaomi; Tominaga, Nozomu; Kawabata, Koji S.; Takaki, Katsutoshi; Kawabata, Miho; Nakaoka, Tatsuya; Ueno, Issei; Akitaya, Hiroshi; Nagayama, Takahiro; Takahashi, Jun; Honda, Satoshi; Omodaka, Toshihiro; Miyanoshita, Ryo; Nagao, Takashi; Watanabe, Makoto; Isogai, Mizuki; Arai, Akira; Itoh, Ryosuke; Ui, Takahiro; Uemura, Makoto; Yoshida, Michitoshi; Hanayama, Hidekazu; Kuroda, Daisuke; Ukita, Nobuharu; Yanagisawa, Kenshi; Izumiura, Hideyuki; Saito, Yoshihiko; Masumoto, Kazunari; Ono, Rikako; Noguchi, Ryo; Matsumoto, Katsura; Nogami, Daisaku; Morokuma, Tomoki; Oasa, Yumiko; Sekiguchi, Kazuhiro

    2016-10-01

    We present extensively dense observations of the super-Chandrasekhar supernova (SC SN) candidate SN 2012dn from -11 to +140 d after the date of its B-band maximum in the optical and near-infrared (NIR) wavelengths conducted through the OISTER ToO (Optical and Infrared Synergetic Telescopes for Education and Research Target of Opportunity) program. The NIR light curves and color evolutions up to 35 days after the B-band maximum provided an excellent match with those of another SC SN 2009dc, providing further support to the nature of SN 2012dn as an SC SN. We found that SN 2012dn exhibited strong excesses in the NIR wavelengths from 30 d after the B-band maximum. The H- and Ks-band light curves exhibited much later maximum dates at 40 and 70 d after the B-band maximum, respectively, compared with those of normal SNe Ia. The H- and Ks-band light curves subtracted by those of SN 2009dc displayed plateaued evolutions, indicating an NIR echo from the surrounding dust. The distance to the inner boundary of the dust shell is limited to 4.8-6.4 × 10-2 pc. No emission lines were found in its early phase spectra, suggesting that the ejecta-circumstellar material interaction could not occur. On the other hand, we found no signature that strongly supports the scenario of dust formation. The mass-loss rate of the pre-explosion system is estimated to be 10-6-10-5 M⊙ yr-1, assuming that the wind velocity of the system is 10-100 km s-1, which suggests that the progenitor of SN 2012dn could be a recurrent nova system. We conclude that the progenitor of this SC SN could be explained by the single-degenerate scenario.

  1. SN 2015bh: NGC 2770's 4th supernova or a luminous blue variable on its way to a Wolf-Rayet star?

    Science.gov (United States)

    Thöne, C. C.; de Ugarte Postigo, A.; Leloudas, G.; Gall, C.; Cano, Z.; Maeda, K.; Schulze, S.; Campana, S.; Wiersema, K.; Groh, J.; de la Rosa, J.; Bauer, F. E.; Malesani, D.; Maund, J.; Morrell, N.; Beletsky, Y.

    2017-03-01

    Very massive stars in the final phases of their lives often show unpredictable outbursts that can mimic supernovae, so-called, "SN impostors", but the distinction is not always straightforward. Here we present observations of a luminous blue variable (LBV) in NGC 2770 in outburst over more than 20 yr that experienced a possible terminal explosion as type IIn SN in 2015, named SN 2015bh. This possible SN (or "main event") had a precursor peaking 40 days before maximum. The total energy release of the main event is 1.8 × 1049 erg, consistent with a single narrow P Cygni profile during the LBV phase and a double P Cygni profile post maximum suggesting an association of the second component with the possible SN. Since 1994 the star has been redder than an LBV in an S-Dor-like outburst. SN 2015bh lies within a spiral arm of NGC 2770 next to several small star-forming regions with a metallicity of 0.5 solar and a stellar population age of 7-10 Myr. SN 2015bh shares many similarities with SN 2009ip and may form a new class of objects that exhibit outbursts a few decades prior to a "hyper eruption" or final core-collapse. If the star survives this event it is undoubtedly altered, and we suggest that these "zombie stars" may evolve from an LBV to a Wolf-Rayet star over the timescale of only a few years. The final fate of these stars can only be determined with observations a decade or more after the SN-like event.

  2. Supernova 1987A: neutrino-driven explosions in three dimensions and light curves

    CERN Document Server

    Utrobin, Victor; Janka, H -Thomas; Mueller, Ewald

    2014-01-01

    The well-studied type IIP SN 1987A, produced by the explosion of a blue supergiant (BSG) star, is a touchstone for massive-star evolution, simulations of neutrino-driven explosions, and modeling of light curves and spectra. In the framework of the neutrino-driven mechanism, we study the dependence of explosion properties on the structure of four different BSGs and compare the corresponding light curves with observations of SN 1987A. We perform 3D simulations with the PROMETHEUS code until about one day and map the results to the 1D code CRAB for the light curve calculations. All of our 3D models with explosion energies compatible with SN 1987A produce 56Ni in rough agreement with the amount deduced from fitting the radioactively powered light-curve tail. One of the progenitors yields maximum velocities of ~3000 km/s for the bulk of ejected 56Ni, consistent with observations. In all of our models inward mixing of hydrogen during the 3D evolution leads to minimum H-velocities below 100 km/s, in good agreement w...

  3. FINDING THE FIRST COSMIC EXPLOSIONS. II. CORE-COLLAPSE SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Whalen, Daniel J. [Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States); Joggerst, Candace C. [T-2, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Fryer, Chris L. [CCS-2, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Stiavelli, Massimo [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Heger, Alexander [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Holz, Daniel E. [Enrico Fermi Institute, Department of Physics, and Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States)

    2013-05-01

    Understanding the properties of Population III (Pop III) stars is prerequisite to elucidating the nature of primeval galaxies, the chemical enrichment and reionization of the early intergalactic medium, and the origin of supermassive black holes. While the primordial initial mass function (IMF) remains unknown, recent evidence from numerical simulations and stellar archaeology suggests that some Pop III stars may have had lower masses than previously thought, 15-50 M{sub Sun} in addition to 50-500 M{sub Sun }. The detection of Pop III supernovae (SNe) by JWST, WFIRST, or the TMT could directly probe the primordial IMF for the first time. We present numerical simulations of 15-40 M{sub Sun} Pop III core-collapse SNe performed with the Los Alamos radiation hydrodynamics code RAGE. We find that they will be visible in the earliest galaxies out to z {approx} 10-15, tracing their star formation rates and in some cases revealing their positions on the sky. Since the central engines of Pop III and solar-metallicity core-collapse SNe are quite similar, future detection of any Type II SNe by next-generation NIR instruments will in general be limited to this epoch.

  4. How Do Type Ia Supernova Nebular Spectra Depend on Explosion Properties? Insights from Systematic Non-LTE Modeling

    Science.gov (United States)

    Botyánszki, János; Kasen, Daniel

    2017-08-01

    We present a radiative transfer code to model the nebular phase spectra of supernovae (SNe) in non-LTE (NLTE). We apply it to a systematic study of SNe Ia using parameterized 1D models and show how nebular spectral features depend on key physical parameters, such as the time since explosion, total ejecta mass, kinetic energy, radial density profile, and the masses of 56Ni, intermediate-mass elements, and stable iron-group elements. We also quantify the impact of uncertainties in atomic data inputs. We find the following. (1) The main features of SN Ia nebular spectra are relatively insensitive to most physical parameters. Degeneracy among parameters precludes a unique determination of the ejecta properties from spectral fitting. In particular, features can be equally well fit with generic Chandrasekhar mass ({M}{ch}), sub-{M}{Ch}, and super-{M}{Ch} models. (2) A sizable (≳0.1 {M}⊙ ) central region of stable iron-group elements, often claimed as evidence for {M}{Ch} models, is not essential to fit the optical spectra and may produce an unusual flat-top [Co iii] profile. (3) The strength of [S iii] emission near 9500 Å can provide a useful diagnostic of explosion nucleosynthesis. (4) Substantial amounts (≳0.1 {M}⊙ ) of unburned C/O mixed throughout the ejecta produce [O iii] emission not seen in observations. (5) Shifts in the wavelength of line peaks can arise from line-blending effects. (6) The steepness of the ejecta density profile affects the line shapes, offering a constraint on explosion models. (7) Uncertainties in atomic data limit the ability to infer physical parameters.

  5. Thermal X-ray emission from shocked ejecta in Type Ia Supernova Remnants. Prospects for explosion mechanism identification

    CERN Document Server

    Badenes, C; Borkowski, K J; Dominguez, I; Badenes, Carles; Bravo, Eduardo; Borkowski, Kazimierz J.; Dominguez, Inmaculada

    2003-01-01

    The explosion mechanism behind Type Ia supernovae is a matter of continuing debate. The diverse attempts to identify or at least constrain the physical processes involved in the explosion have been only partially successful so far. In this paper we propose to use the thermal X-ray emission from young supernova remnants originated in Type Ia events to extract relevant information concerning the explosions themselves. We have produced a grid of thermonuclear supernova models representative of the paradigms currently under debate: pure deflagrations, delayed detonations, pulsating delayed detonations and sub-Chandrasekhar explosions, using their density and chemical composition profiles to simulate the interaction with the surrounding ambient medium and the ensuing plasma heating, non-equilibrium ionization and thermal X-ray emission of the ejecta. Key observational parameters such as electron temperatures, emission measures and ionization time scales are presented and discussed. We find that not only is it poss...

  6. Hubble Space Telescope and Ground-Based Observations of the Type Iax Supernovae SN 2005hk and SN 2008A

    CERN Document Server

    McCully, Curtis; Foley, Ryan J; Chornock, Ryan; Holtzman, Jon A; Balam, David D; Branch, David; Filippenko, Alexei V; Frieman, Joshua; Fynbo, Johan; Galbany, Lluis; Ganeshalingam, Mohan; Garnavich, Peter M; Graham, Melissa L; Hsiao, Eric Y; Leloudas, Giorgos; Leonard, Douglas C; Li, Weidong; Riess, Adam G; Sako, Masao; Schneider, Donald P; Silverman, Jeffrey M; Sollerman, Jesper; Steele, Thea N; Thomas, Rollin C; Wheeler, J Craig; Zheng, Chen

    2013-01-01

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). These objects are peculiar cousins of normal Type Ia SNe, with SN 2002cx as the prototype. Here we focus on late-time observations, where these objects deviate most dramatically from normal SNe Ia. Instead of the dominant nebular emission lines that are observed in normal SNe Ia at late phases (and indeed, in SNe of all other types), spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with n_e >~ 10^9 cm^-3. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected "infrared catastrophe," a generic feature of SN Ia models. However, our HST photom...

  7. Neutrino-Nucleus Reaction Cross Sections for Light Element Synthesis in Supernova Explosions

    CERN Document Server

    Yoshida, T; Chiba, S; Kajino, T; Yokomakura, H; Kimura, K; Takamura, A; Hartmann, D H

    2008-01-01

    The neutrino-nucleus reaction cross sections of 4He and 12C are evaluated using new shell model Hamiltonians. Branching ratios of various decay channels are calculated to evaluate the yields of Li, Be, and B produced through the nu-process in supernova explosions. The new cross sections enhance the yields of 7Li and 11B produced during the supernova explosion of a 16.2 M_odot star model compared to the case using the conventional cross sections by about 10%. On the other hand, the yield of 10B decreases by a factor of two. The yields of 6Li, 9Be, and the radioactive nucleus 10Be are found at a level of 10^{-11} M_odot. The temperature of nu_{mu,tau}- and bar{nu}_{mu,tau}-neutrinos inferred from the supernova contribution of 11B in Galactic chemical evolution models is constrained to the 4.3 MeV to 6.5 MeV range. The increase in the 7Li and 11B yields due to neutrino oscillations is demonstrated with the new cross sections.

  8. Finding the First Cosmic Explosions. IV. 90 - 140 M$_{\\odot}$ Pair-Instability Supernovae

    CERN Document Server

    Smidt, Joseph; Chatzopoulos, E; Wiggins, Brandon K; Chen, Ke-Jung; Kozyreva, Alexandra; Even, Wesley

    2014-01-01

    Population III stars that die as pair-instability supernovae are usually thought to fall in the mass range of 140 - 260 M$_{\\odot}$. But several lines of work have now shown that rotation can build up the He cores needed to encounter the pair instability at stellar masses as low as 90 $_{\\odot}$. Depending on the slope of the initial mass function of Population III stars, there could be 4 - 5 times as many stars from 90 - 140 $_{\\odot}$ in the primordial universe than in the usually accepted range. We present numerical simulations of the pair-instability explosions of such stars performed with the MESA, FLASH and RAGE codes. We find that they will be visible to supernova factories such as Pan-STARRS and LSST in the optical out to z $\\sim$ 1 - 2 and to JWST and the 30 m-class telescopes in the NIR out to $z \\sim$ 7 - 10. Such explosions will thus probe the stellar populations of the first galaxies and cosmic star formation rates in the era of cosmological reionization. These supernovae are also easily distingu...

  9. Early observations of the nearby Type Ia supernova SN 2015F

    Science.gov (United States)

    Cartier, R.; Sullivan, M.; Firth, R. E.; Pignata, G.; Mazzali, P.; Maguire, K.; Childress, M. J.; Arcavi, I.; Ashall, C.; Bassett, B.; Crawford, S. M.; Frohmaier, C.; Galbany, L.; Gal-Yam, A.; Hosseinzadeh, G.; Howell, D. A.; Inserra, C.; Johansson, J.; Kasai, E. K.; McCully, C.; Prajs, S.; Prentice, S.; Schulze, S.; Smartt, S. J.; Smith, K. W.; Smith, M.; Valenti, S.; Young, D. R.

    2017-02-01

    We present photometry and time series spectroscopy of the nearby Type Ia supernova (SN Ia) SN 2015F over -16 d to +80 d relative to maximum light, obtained as part of the Public ESO Spectroscopic Survey of Transient Objects. SN 2015F is a slightly sub-luminous SN Ia with a decline rate of Δm15(B) = 1.35 ± 0.03 mag, placing it in the region between normal and SN 1991bg-like events. Our densely sampled photometric data place tight constraints on the epoch of first light and form of the early-time light curve. The spectra exhibit photospheric C II λ6580 absorption until -4 days, and high-velocity Ca II is particularly strong at 14 000 km s-1, suggesting mixing in the outermost layers of the SN ejecta. Although unusual in SN Ia spectra, including V II in the modelling significantly improves the spectral fits. Intriguingly, we detect an absorption feature at ˜6800 Å that persists until maximum light. Our favoured explanation for this line is photospheric Al II, which has never been claimed before in SNe Ia, although detached high-velocity C II material could also be responsible. In both cases, the absorbing material seems to be confined to a relatively narrow region in velocity space. The nucleosynthesis of detectable amounts of Al II would argue against a low-metallicity white dwarf progenitor. We also show that this 6800 Å feature is weakly present in other normal SN Ia events and common in the SN 1991bg-like sub-class.

  10. Neutrino Signal of Collapse-induced Thermonuclear Supernovae: The Case for Prompt Black Hole Formation in SN 1987A

    Science.gov (United States)

    Blum, Kfir; Kushnir, Doron

    2016-09-01

    Collapse-induced thermonuclear explosion (CITE) may explain core-collapse supernovae (CCSNe). We analyze the neutrino signal in CITE and compare it to the neutrino burst of SN 1987A. For strong (≳ {10}51 erg) CCSNe, such as SN 1987A, CITE predicts a proto-neutron star (PNS) accretion phase lasting up to a few seconds that is cut off by black hole (BH) formation. The neutrino luminosity can later be revived by accretion disk emission after a dead time of a few to a few tens of seconds. In contrast, the neutrino mechanism for CCSNe predicts a short (≲s) PNS accretion phase, followed by slowly declining PNS cooling luminosity. We repeat statistical analyses used in the literature to interpret the neutrino mechanism, and apply them to CITE. The first 1-2 s of the neutrino burst are equally compatible with CITE and with the neutrino mechanism. However, the data points toward a luminosity drop at t = 2-3 s, which is in some tension with the neutrino mechanism but can be naturally attributed to BH formation in CITE. The occurrence of neutrino signal events at 5 s suggests that, within CITE, the accretion disk formed by that time. We perform two-dimensional numerical simulations showing that CITE may be able to accommodate this disk formation time while reproducing the ejected 56Ni mass and ejecta kinetic energy within factors of 2-3 of observations. We estimate the accretion disk neutrino luminosity, finding it to be on the low side but compatible with the data to a factor of 10. Given comparable uncertainties in the disk luminosity simulation, we conclude that direct BH formation may have occurred in SN 1987A.

  11. SN 2015U: a rapidly evolving and luminous Type Ibn supernova

    Science.gov (United States)

    Shivvers, Isaac; Zheng, Wei Kang; Mauerhan, Jon; Kleiser, Io K. W.; Van Dyk, Schuyler D.; Silverman, Jeffrey M.; Graham, Melissa L.; Kelly, Patrick L.; Filippenko, Alexei V.; Kumar, Sahana

    2016-09-01

    Supernova (SN) 2015U (also known as PSN J07285387+3349106) was discovered in NGC 2388 on 2015 Feb. 11. A rapidly evolving and luminous event, it showed effectively hydrogen-free spectra dominated by relatively narrow helium P-Cygni spectral features and it was classified as an SN Ibn. In this paper, we present photometric, spectroscopic, and spectropolarimetric observations of SN 2015U, including a Keck/DEIMOS spectrum (resolution ≈5000) which fully resolves the optical emission and absorption features. We find that SN 2015U is best understood via models of shock breakout from extended and dense circumstellar material (CSM), likely created by a history of mass-loss from the progenitor with an extreme outburst within ˜1-2 yr of core collapse (but we do not detect any outburst in our archival imaging of NGC 2388). We argue that the high luminosity of SN 2015U was powered not through 56Ni decay but via the deposition of kinetic energy into the ejecta/CSM shock interface. Though our analysis is hampered by strong host-galaxy dust obscuration (which likely exhibits multiple components), our data set makes SN 2015U one of the best-studied Type Ibn SNe and provides a bridge of understanding to other rapidly fading transients, both luminous and relatively faint.

  12. Inferring the core-collapse supernova explosion mechanism with gravitational waves

    CERN Document Server

    Powell, Jade; Logue, Joshua; Heng, Ik Siong

    2016-01-01

    A detection of a core-collapse supernova (CCSN) gravitational-wave (GW) signal with an Advanced LIGO and Virgo detector network may allow us to measure astrophysical parameters of the dying massive star. GWs are emitted from deep inside the core and, as such, they are direct probes of the CCSN explosion mechanism. In this study we show how we can determine the CCSN explosion mechanism from a GW supernova detection using a combination of principal component analysis and Bayesian model selection. We use simulations of GW signals from CCSN exploding via neutrino-driven convection and rapidly-rotating core collapse. Previous studies have shown that the explosion mechanism can be determined using one LIGO detector and simulated Gaussian noise. As real GW detector noise is both non-stationary and non-Gaussian we use real detector noise from a network of detectors with a sensitivity altered to match the advanced detectors design sensitivity. For the first time we carry out a careful selection of the number of princi...

  13. Effect of Quark Strong Interaction in Phase Transition on Supernova Explosion

    Institute of Scientific and Technical Information of China (English)

    LAI Xiang-Jun; LUO Zhi-Quan; LIU Jing-Jing; LIU Hong-Lin

    2008-01-01

    The effect of quark interactions perturbatively to order αc on the conversion, from quark matter to strange quark matter, is studied systematically based on a recent set of current quark masses. The process has a significant effect on increasing the core temperature, the neutrino abundance and the neutrino energies even if there is no quark interaction. Furthermore, with the switch of the strong interaction among quarks, these quantities will increase respectively to some further extents with αc increase. Taking αc = 0.47 as an example, the temperature, the neutrino abundance and the total neutrino energies are further raised by about 10%, 7%, and 20% respectively, which is weakly dependent on the initial temperature. Combining the effect of the current quark mass and the effect of the quark strong interaction, the results of the conversions will greatly enhance the probability of success for a supernova explosion and deeply influence the dynamics of the supernova evolution.

  14. 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.

  15. Progenitors of supernova Ibc: a single Wolf-Rayet star as the possible progenitor of the SN Ib iPTF13bvn

    CERN Document Server

    Groh, Jose H; Ekstrom, Sylvia

    2013-01-01

    Core-collapse supernova (SN) explosions mark the end of the tumultuous life of massive stars. Determining the nature of their progenitors is a crucial step towards understanding the properties of SNe. Until recently, no progenitor has been directly detected for SN of type Ibc, which are believed to come from massive stars that lose their Hydrogen envelope through stellar winds and from binary systems where the companion has stripped the H envelope from the primary. Here we analyze recently-reported observations of iPTF13bvn, which could possibly be the first detection of a SN Ib progenitor based on pre-explosion images. Very interestingly, the recently published Geneva models of single stars can reproduce the observed photometry of the progenitor candidate and its mass-loss rate, confirming the scenario from Cao et al 2013. We find that a single WR star with initial mass in the range 31-35 Msun fits the observed photometry of the progenitor of iPTF13bvn. The progenitor likely has a luminosity of log (L/Lsun)~...

  16. X-ray and radio emission from Type In supernova SN 2010jl

    CERN Document Server

    Chandra, Poonam; Chugai, Nikolai; Fransson, Claes; Soderberg, Alicia M

    2015-01-01

    We present all X-ray and radio observations of the Type IIn supernova SN 2010jl. The X-ray observations cover a period up to day 1500 with Chandra, XMM-Newton, NuSTAR and Swift-XRT. The Chandra observations after 2012 June, the XMM-Newton observation in 2013 November, and most of the Swift-XRT observations until 2014 December are presented for the first time. All the spectra can be fitted by an absorbed hot thermal model except for \\chandra spectra on 2011 October and 2012 June when an additional component is needed. Although the origin of this component is uncertain, it is spatially coincident with the supernova and occurs when there are changes to the supernova spectrum in the energy range close to that of the extra component, indicating that the emission is related to the supernova. The X-ray light curve shows an initial plateau followed by a steep drop starting at day $\\sim 300$. We attribute the drop to a decrease in the circumstellar density. The column density to the X-ray emission drops rapidly with t...

  17. SN1991bg-like supernovae are a compelling source of most Galactic antimatter

    Science.gov (United States)

    Panther, Fiona H.; Crocker, Roland M.; Seitenzahl, Ivo R.; Ruiter, Ashley J.

    2017-01-01

    The Milky Way Galaxy glows with the soft gamma ray emission resulting from the annihilation of ~5 × 1043 electron-positron pairs every second. The origin of this vast quantity of antimatter and the peculiar morphology of the 511keV gamma ray line resulting from this annihilation have been the subject of debate for almost half a century. Most obvious positron sources are associated with star forming regions and cannot explain the rate of positron annihilation in the Galactic bulge, which last saw star formation some 10 Gyr ago, or else violate stringent constraints on the positron injection energy. Radioactive decay of elements formed in core collapse supernovae (CCSNe) and normal Type Ia supernovae (SNe Ia) could supply positrons matching the injection energy constraints but the distribution of such potential sources does not replicate the required morphology. We show that a single class of peculiar thermonuclear supernova - SN1991bg-like supernovae (SNe 91bg) - can supply the number and distribution of positrons we see annihilating in the Galaxy through the decay of 44Ti synthesised in these events. Such 44Ti production simultaneously addresses the observed abundance of 44Ca, the 44Ti decay product, in solar system material.

  18. SN1991bg-like supernovae are a compelling source of most Galactic antimatter

    CERN Document Server

    Panther, Fiona H

    2016-01-01

    The Milky Way Galaxy glows with the soft gamma ray emission resulting from the annihilation of $\\sim 5 \\times 10^{43}$ electron-positron pairs every second. The origin of this vast quantity of antimatter and the peculiar morphology of the 511keV gamma ray line resulting from this annihilation have been the subject of debate for almost half a century. Most obvious positron sources are associated with star forming regions and cannot explain the rate of positron annihilation in the Galactic bulge, which last saw star formation some $10\\,\\mathrm{Gyr}$ ago, or else violate stringent constraints on the positron injection energy. Radioactive decay of elements formed in core collapse supernovae (CCSNe) and normal Type Ia supernovae (SNe Ia) could supply positrons matching the injection energy constraints but the distribution of such potential sources does not replicate the required morphology. We show that a single class of peculiar thermonuclear supernova - SN1991bg-like supernovae (SNe 91bg) - can supply the number...

  19. SN 2013ej - A type IIL supernova with weak signs of interaction

    CERN Document Server

    Bose, Subhash; Kumar, Brijesh; Duggal, Chetna; Misra, Kuntal; Brown, Peter J; Singh, Mridweeka; Dwarkadas, Vikram; York, Donald G; Chakraborti, Sayan; Chandola, H C; Dahlstrom, Julie; Ray, Alak; Safonova, Margarita

    2015-01-01

    We present optical photometric and spectroscopic observations of supernova 2013ej. It is one of the brightest type II supernovae exploded in a nearby ($\\sim 10$ Mpc) galaxy NGC 628. The light curve characteristics are similar to type II SNe, but with a relatively shorter ($ \\sim85 $ day) and steeper ($ \\sim1.7 $ mag (100 d)$^{-1} $ in V) plateau phase. The SN shows a large drop of 2.4 mag in V band brightness during plateau to nebular transition. The absolute ultraviolet (UV) light curves are identical to SN 2012aw, showing a similar UV plateau trend extending up to 85 days. The radioactive $^{56}$Ni mass estimated from the tail luminosity is $ 0.02 $M$_{\\odot}$ which is significantly lower than typical type IIP SNe. The characteristics of spectral features and evolution of line velocities indicate that SN 2013ej is a type II event. However, light curve characteristics and some spectroscopic features provide strong support in classifying it as a type IIL event. A detailed SYNOW modelling of spectra indicates ...

  20. Implications of turbulence for jets in core-collapse supernova explosions

    CERN Document Server

    Gilkis, Avishai

    2014-01-01

    We show that turbulence in core collapse supernovae (CCSNe) which has been shown recently to ease shock revival can also lead to the formation of intermittent thick accretion disks, or accretion belts, around the newly born neutron star (NS). The accretion morphology is such that two low density funnels are formed along the polar directions. The disks then are likely to launch jets with a varying axis direction, i.e., jittering-jets, through the two opposite funnels. The energy contribution of jets in this jittering jets mechanism can result in an explosion energy of E>10^51erg, even without reviving the stalled shock. We strengthen the jittering jets mechanism as a prominent explosion mechanism of CCSNe.

  1. SN 2015U: A Rapidly Evolving and Luminous Type Ibn Supernova

    CERN Document Server

    Shivvers, Isaac; Mauerhan, Jon; Kleiser, Io K W; Kelly, Patrick L; Silverman, Jeffrey M; Graham, Melissa L; Filippenko, Alexei V; Kumar, Sahana; Van Dyk, Schuyler D

    2016-01-01

    Supernova (SN) 2015U (also known as PSN J07285387+3349106) was discovered in NGC 2388 on 2015 Feb. 11. A rapidly evolving and luminous event, it showed hydrogen-free spectra dominated by relatively narrow helium P-Cygni spectral features and it was classified as a SN Ibn. In this paper we present photometric, spectroscopic, and spectropolarimetric observations of SN 2015U, including a Keck/DEIMOS spectrum (resolution $\\approx 5000$) which fully resolves the optical emission and absorption features. We find that SN 2015U is best understood via models of shock breakout from extended and dense circumstellar material (CSM), likely created by a history of mass loss from the progenitor with an extreme outburst within $\\sim$1-2 yr of core collapse (but we do not detect any outburst in our archival imaging of NGC 2388). We argue that the high luminosity of SN 2015U was powered not through $^{56}$Ni decay but via the deposition of kinetic energy into the ejecta/CSM shock interface, and we place an upper limit on the a...

  2. SN Refsdal : Photometry and Time Delay Measurements of the First Einstein Cross Supernova

    CERN Document Server

    Rodney, S A; Kelly, P L; Bradac, M; Brammer, G; Filippenko, A V; Foley, R J; Graur, O; Hjorth, J; Jha, S W; McCully, C; Molino, A; Riess, A G; Schmidt, K B; Selsing, J; Sharon, K; Treu, T; Weiner, B J; Zitrin, A

    2015-01-01

    We present the first year of Hubble Space Telescope imaging of the unique supernova (SN) 'Refsdal', a gravitationally lensed SN at z=1.488 +- 0.001 with multiple images behind the galaxy cluster MACS J1149.6+2223. The first four observed images of SN Refsdal (images S1-S4) exhibited a slow rise (over ~150 days) to reach a broad peak brightness around 20 April, 2015. Using a set of light curve templates constructed from the family of SN 1987A-like peculiar Type II SNe, we measure time delays for the four images relative to S1 of 4+-4 (for S2), 2+-5 (S3), and 24+-7 days (S4). The measured magnification ratios relative to S1 are 1.15+-0.05 (S2), 1.01+-0.04 (S3), and 0.34+-0.02 (S4). We find, however, that none of the template light curves fully captures the photometric behavior of SN Refsdal, so we also derive complementary measurements for these parameters using polynomials to represent the intrinsic light curve shape. These more flexible fits deliver fully consistent time delays of 7+-2 days (S2), 0.6+-3 days ...

  3. Analysis of the flux and polarization spectra of the type Ia supernova SN 2001el: Exploring the geometry of the high-velocity Ejecta

    Energy Technology Data Exchange (ETDEWEB)

    Kasen, Daniel; Nugent, Peter; Wang, Lifan; Howell, D.A.; Wheeler, J. Craig; Hoeflich, Peter; Baade, Dietrich; Baron, E.; Hauschildt, P.H.

    2003-01-15

    SN 2001el is the first normal Type Ia supernova to show a strong, intrinsic polarization signal. In addition, during the epochs prior to maximum light, the CaII IR triplet absorption is seen distinctly and separately at both normal photospheric velocities and at very high velocities. The unusual, high-velocity triplet absorption is highly polarized, with a different polarization angle than the rest of the spectrum. The unique observation allows us to construct a relatively detailed picture of the layered geometrical structure of the supernova ejecta: in our interpretation, the ejecta layers near the photosphere (v approximately 10,000 km/s) obey a near axial symmetry, while a detached, high-velocity structure (v approximately 18,000-25,000 $ km/s) of CaII line opacity deviates from the photospheric axisymmetry. By partially obscuring the underlying photosphere, the high-velocity structure causes a more incomplete cancellation of the polarization of the photospheric light, and so gives rise to the polarization peak of the high-velocity IR triplet feature. In an effort to constrain the ejecta geometry, we develop a technique for calculating 3-D synthetic polarization spectra and use it to generate polarization profiles for several parameterized configurations. In particular, we examine the case where the inner ejecta layers are ellipsoidal and the outer, high-velocity structure is one of four possibilities: a spherical shell, an ellipsoidal shell, a clumped shell, or a toroid. The synthetic spectra rule out the clearly discriminated if observations are obtained from several different lines of sight. Thus, assuming the high velocity structure observed for SN 2001el is a consistent feature of at least known subset of type Ia supernovae, future observations and analyses such as these may allow one to put strong constraints on the ejecta geometry and hence on supernova progenitors and explosion mechanisms.

  4. The Role of Waves in the Explosion Mechanism of Core-Collapse Supernovae

    Science.gov (United States)

    Gossan, Sarah; Fuller, Jim; Roberts, Luke

    2017-01-01

    The core-collapse supernova (CCSN) explosion mechanism is not well understood. For garden variety CCSNe, the favored explosion scenario is delayed revival of the stalled shock powered by neutrino-driven convection. Despite huge computational advances, many simulations must use parameterized `light-bulb' models for neutrino heating or mask out inner regions of the proto-neutron star (PNS) for computational efficiency. These approximations can fail to capture hydrodynamical processes in the PNS core where nearly all the binding energy resides, and from which much of the explosion energy may originate. We show that gravity waves excited by core PNS convection may represent a significant heating source for the post-shock region. Using 1D simulations, we calculate the wave heating rate in the post-shock region out to one second after core bounce, showing that wave heating rates in excess of 1051 erg/s may persist for several hundreds of milliseconds, even after neutrino heating rates have decreased. Waves excited by PNS convection may therefore significantly contribute to shock revival and, subsequently, a successful and energetic explosion. We discuss how simulations can miss the effect of waves, and how future simulations can more accurately quantify wave heating rates.

  5. Five Years in the Mid-Infrared Development of the SN 1987A Supernova Remnant

    Science.gov (United States)

    Dwek, Eliahu

    2009-01-01

    Spitzer has been used to monitor the mid-IR evolution of SN 1987A over a 5 year period as it develops into a supernova remnant through interaction with its surrounding environment. This interaction is dominated by the collision of the ejecta with the pre-existing equatorial ring. The mid-IR continuum indicates an increasing mass of shock-heated silicate dust, but without any significant change in temperature of the dust grains. Comparison of the IR and X-ray evolution of the remnant can be used to infer plasma conditions and the processing of the dust in the shock-heated X-ray emitting gas.

  6. SALT spectroscopic classification of DLT17ar (= SN 2017cyy) as a type-Ia supernova before maximum light

    Science.gov (United States)

    Jha, S. W.; Sand, D.; Tartaglia, L.; Valenti, S.; Kuhn, R.

    2017-04-01

    We obtained SALT (+RSS) spectroscopy of DLT17ar (= SN 2017cyy) on 2017 Apr 12.8 UT, covering the wavelength range 350-725 nm under cloudy conditions. Cross-correlation of the noisy supernova spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows DLT17ar is a type-Ia supernova before maximum light.

  7. SALT spectroscopic classification of ASASSN-17bu (= SN 2017yv) as a type-Ia supernova before maximum light

    Science.gov (United States)

    Jha, S. W.; Kotze, M.

    2017-02-01

    We obtained SALT (+RSS) spectroscopy of ASASSN-17bu (= SN 2017yv; ATel #10033) on 2017 Feb 3.9 UT, covering the wavelength range 350-940 nm. Cross-correlation of the supernova spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows ASASSN-17bu is a type-Ia supernova several days before maximum light.

  8. Constraining Explosion Type of Young Supernova Remnants Using 24 Micron Emission Morphology

    CERN Document Server

    Peters, Charee L; Ramirez-Ruiz, Enrico; Stassun, Keivan G; Figueroa-Feliciano, Enectali

    2013-01-01

    Determination of the explosion type of supernova remnants (SNRs) can be challenging, as SNRs are hundreds to thousands of years old and supernovae (SNe) are classified based on spectral properties days after explosion. Previous studies of thermal X-ray emission from Milky Way and Large Magellanic Cloud (LMC) SNRs have shown that Type Ia and core-collapse (CC) SNRs have statistically different symmetries, and thus these sources can be typed based on their X-ray morphologies. In this paper, we extend the same technique, a multipole expansion technique using power ratios, to infrared (IR) images of SNRs to test whether they can be typed using the symmetry of their warm dust emission as well. We analyzed archival Spitzer Space Telescope Multiband Imaging Photometer (MIPS) 24 micron observations of the previously used X-ray sample, and we find that the two classes of SNRs separate according to their IR morphologies. The Type Ia SNRs are statistically more circular and mirror symmetric than the CC SNRs, likely due ...

  9. SN~2012cg: Evidence for Interaction Between a Normal Type Ia Supernova and a Non-degenerate Binary Companion

    Science.gov (United States)

    Marion, G. H.; Brown, Peter J.; Vinkó, Jozsef; Silverman, Jeffrey M.; Sand, David J.; Challis, Peter; Kirshner, Robert P.; Wheeler, J. Craig; Berlind, Perry; Brown, Warren R.; Calkins, Michael L.; Camacho, Yssavo; Dhungana, Govinda; Foley, Ryan J.; Friedman, Andrew S.; Graham, Melissa L.; Howell, D. Andrew; Hsiao, Eric Y.; Irwin, Jonathan M.; Jha, Saurabh W.; Kehoe, Robert; Macri, Lucas M.; Maeda, Keiichi; Mandel, Kaisey; McCully, Curtis; Pandya, Viraj; Rines, Kenneth J.; Wilhelmy, Steven; Zheng, Weikang

    2016-04-01

    We report evidence for excess blue light from the Type Ia supernova (Sn Ia) SN 2012cg at 15 and 16 days before maximum B-band brightness. The emission is consistent with predictions for the impact of the supernova on a non-degenerate binary companion. This is the first evidence for emission from a companion to a normal SN Ia. Sixteen days before maximum light, the B-V color of SN 2012cg is 0.2 mag bluer than for other normal SN Ia. At later times, this supernova has a typical SN Ia light curve, with extinction-corrected {M}B=-19.62+/- 0.02 mag and {{Δ }}{m}15(B)=0.86+/- 0.02. Our data set is extensive, with photometry in seven filters from five independent sources. Early spectra also show the effects of blue light, and high-velocity features are observed at early times. Near maximum, the spectra are normal with a silicon velocity vSi = -10,500 km s-1. Comparing the early data with models by Kasen favors a main-sequence companion of about six solar masses. It is possible that many other SN Ia have main-sequence companions that have eluded detection because the emission from the impact is fleeting and faint.

  10. SALT spectroscopic classification of SN 2016iae (= ATLAS16dvr) as a type-Ic supernova before maximum light

    Science.gov (United States)

    Jha, S. W.; Foley, R. J.; Skelton, R.

    2016-11-01

    We obtained SALT (+RSS) spectroscopy of SN 2016iae (= ATLAS16dvr; Tonry et al. 2016, ATel #9749) on 2016 Nov 12.9 UT covering the wavelength range 350-940 nm. The spectrum shows a relatively blue continuum, with well-developed broad absorption features, including strong Si II (rest 635.5 nm). Cross-correlation of the supernova spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows SN 2016iae is a type-Ic supernova approaching maximum light.

  11. SN 2003du: 480 days in the Life of a Normal Type Ia Supernova

    CERN Document Server

    Stanishev, V; Benetti, S; Kotak, R; Pignata, G; Navasardyan, H; Mazzali, P A; Amanullah, R; Garavini, G; Nobili, S; Qiu, Y; Elias-Rosa, N; Ruiz-Lapuente, P; Méndez, J; Meikle, P; Patat, F; Pastorello, A; Altavilla, G; Gustafsson, M; Harutyunyan, A; Iijima, T; Jakobsson, P; Kichizhieva, M V; Lundqvist, P; Mattila, S; Melinder, J; Pavlenko, E P; Pavlyuk, N N; Sollerman, J; Tsvetkov, D Yu; Turatto, M; Hillebrandt, W

    2007-01-01

    An extensive set of optical and NIR photometry and low-resolution spectra the Type Ia supernova (SN Ia) 2003du was obtained using a number of facilities. The observations started 13 days before B-band maximum light and continued for 480 days with exceptionally good time sampling. The optical photometry was calibrated through the S-correction technique. The UBVRIJHK light curves and the color indices of SN 2003du closely resemble those of normal SNe Ia. SN 2003du reached a B-band maximum of 13.49 (+/-0.02) mag on JD2452766.38 (+/-0.5). We derive a B-band stretch parameter of 0.988 (+/-0.003), which corresponds to dM15=1.02 (+/-0.05), indicative of a SN Ia of standard luminosity. The reddening in the host galaxy was estimated by three methods, and was consistently found to be negligible. We estimate a distance modulus of 32.79 (+/-0.15) mag to the host galaxy, UGC 9391. The peak UVOIR bolometric luminosity of 1.35(+/-0.20) 10^43 erg/s and Arnett's rule implies that M(Ni56)=0.68 (+/-0.14)M_sun of Ni56 was synthe...

  12. Inverse Compton X-ray Emission from Supernovae with Compact Progenitors: Application to SN2011fe

    CERN Document Server

    Margutti, R; Chomiuk, L; Chevalier, R; Hurley, K; Milisavljevic, D; Foley, R J; Hughes, J P; Slane, P; Fransson, C; Moe, M; Barthelmy, S; Boynton, W; Briggs, M; Connaughton, V; Costa, E; Cummings, J; Del Monte, E; Enos, H; Fellows, C; Feroci, M; Fukazawa, Y; Gehrels, N; Goldsten, J; Golovin, D; Hanabata, Y; Harshman, K; Krimm, H; Litvak, M L; Makishima, K; Marisaldi, M; Mitrofanov, I G; Murakami, T; Ohno, M; Palmer, D M; Sanin, A B; Starr, R; Svinkin, D

    2012-01-01

    We present a generalized analytic formalism for the inverse Compton X-ray emission from hydrogen-poor supernovae and apply this framework to SN2011fe using Swift-XRT, UVOT and Chandra observations. We characterize the optical properties of SN2011fe in the Swift bands and find them to be broadly consistent with a "normal" SN Ia, however, no X-ray source is detected by either XRT or Chandra. We constrain the progenitor system mass loss rate to be lower than 2x10^-9 M_sun/yr (3sigma c.l.) for wind velocity v_w=100 km/s. Our result rules out symbiotic binary progenitors for SN2011fe and argues against Roche-lobe overflowing subgiants and main sequence secondary stars if >1% of the transferred mass is lost at the Lagrangian points. Regardless of the density profile, the X-ray non-detections are suggestive of a clean environment (particle density < 150 cm-3) for (2x10^15

  13. The Supernova Impostor Impostor SN 1961V: Spitzer Shows That Zwicky Was Right (Again)

    CERN Document Server

    Kochanek, C S; Stanek, K Z

    2010-01-01

    SN 1961V, one of Zwicky's defining Type V supernovae (SN), was a peculiar transient in NGC 1058 that has variously been categorized as either a true core collapse SN leaving a black hole (BH) or neutron star (NS) remnant, or an eruption of a luminous blue variable (LBV) star. The former case is suggested by its association with a decaying non-thermal radio source, while the latter is suggested by its peculiar transient light curve and its low initial expansion velocities. The crucial difference is that the star survives a transient eruption but not an SN. All stars identified as possible survivors are significantly fainter, L_opt ~ 10^5 Lsun, than the L_opt ~ 3 10^6 Lsun progenitor star at optical wavelengths. While this can be explained by dust absorption in a shell of material ejected during the transient, the survivor must then be present as a L_IR ~ 3 10^6 Lsun mid-infrared source. Using archival Spitzer observations of the region, we show that such a luminous mid-IR source is not present. The brightest s...

  14. The nature of blast-wave-driven interfacial instabilities - important implications for modeling supernovae explosions

    Science.gov (United States)

    Miles, Aaron

    2004-11-01

    In this talk we discuss the nature of late-time, broad-banded instability development at an interface when a strong blast wave travels from a heavier to lighter fluid, as is the case in a supernova explosion. After a short period of Richtmyer-Meshkov growth, the interface is unstable via the Rayleigh-Taylor mechanism, which rapidly becomes the dominant energy source for growth. This situation is distinct from the classical case in two important ways, both of which can be understood in terms of a bubble merger model we have developed for blast-wave-driven systems. Rather than the constant acceleration feeding the instability to spawn ever larger scales and accelerate the growth, the decaying acceleration in the blast-wave case leads to a decay in the RT growth rate, and a freezing in of a preferred largest scale, which is dependent on the precise details of the system. In the language of bubble-merger models, this can be understood in terms of the time for the generation of the next largest scale being longer than the lifetime of the blast wave. Secondly, the continual expansion behind the blast front precludes the emergence of a self-similar regime, independent of the initial conditions, in the planar case. Self-similarity may be recovered in diverging systems but may be difficult to observe in reality because of rather restrictive conditions that must be met. These observations are borne out by hi-resolution numerical simulations using the higher order Godunov AMR hydrocode Raptor in 2 and 3D, and explain other simulations of instability growth in supernovae explosions; the initial "interfacial" structure is likely very important in determining the late-time growth. The model predictions are also consistent with numerous images of natural and manmade explosions.

  15. The Role of Waves in the Explosion Mechanism of Core-Collapse Supernovae

    Science.gov (United States)

    Gossan, Sarah; Fuller, Jim; Roberts, Luke

    2017-01-01

    The core-collapse supernova (CCSN) explosion mechanism is not well understood. For garden variety CCSNe, the favored scenario for explosion is delayed revival of the stalled shock powered by neutrino-driven convection. Despite tremendous computational advances, many simulations must use parameterized ‘light-bulb’ models for neutrino heating or mask out inner regions of the proto-neutron star (PNS) for computational efficiency. These approximations can fail to capture hydrodynamical processes in the core of the PNS where nearly all the binding energy resides, and from which much of the explosion energy may originate. We show that gravity (buoyancy) waves excited by core PNS convection (within the central 20 km of the PNS) may represent a significant heating source for the post-shock region. The gravity waves propagate out of the PNS and transform into acoustic waves before depositing their energy at the shock, converting a small fraction of the PNS binding energy into explosion energy. Using 1D simulations, we calculate the wave heating rate in the post-shock region out to one second after core bounce, showing that wave heating rates in excess of 1051 erg/s may persist for several hundreds of milliseconds, even after neutrino heating rates have declined to smaller values. Waves excited by PNS convection may therefore significantly contribute to shock revival and, subsequently, a successful and energetic explosion. We discuss how simulations can miss the effect of waves (or have not recognized them), and how future simulations can more accurately quantify wave heating rates.

  16. Core-collapse explosions of Wolf–Rayet stars and the connection to Type IIb/Ib/Ic supernovae

    NARCIS (Netherlands)

    Dessart, L.; Hillier, D.J.; Livne, E.; Yoon, S.C.; Woosley, S.E.; Waldman, R.; Langer, N.

    2011-01-01

    We present non-Local Thermodynamic Equilibrium (LTE) time-dependent radiative-transfer simulations of supernova (SN) IIb/Ib/Ic spectra and light curves, based on ∼1051 erg pistondriven ejecta, with and without 56Ni, produced from single and binary Wolf–Rayet (WR) stars evolved at solar and sub-solar

  17. SN 2009js at the crossroads between normal and subluminous Type IIP supernovae: optical and mid-infrared evolution

    CERN Document Server

    Gandhi, P; Tanaka, M; Nozawa, T; Kawabata, K S; Saviane, I; Maeda, K; Moriya, T J; Hattori, T; Sasada, M; Itoh, R

    2013-01-01

    We present a study of SN 2009js in NGC 918. Multi-band Kanata optical photometry covering the first ~120 days show the source to be a Type IIP SN. Reddening is dominated by that due to our Galaxy. One-year-post-explosion photometry with the NTT, and a Subaru optical spectrum 16 days post-discovery, both imply a good match with the well-studied subluminous SN 2005cs. The plateau phase luminosity of SN 2009js and its plateau duration are more similar to the intermediate luminosity IIP SN 2008in. Thus, SN 2009js shares characteristics with both subluminous and intermediate luminosity SNe. Its radioactive tail luminosity lies between SN 2005cs and SN 2008in, whereas its quasi-bolometric luminosity decline from peak to plateau (quantified by a newly-defined parameter Delta[logL] measuring adiabatic cooling following shock breakout) is much smaller than both the others. We estimate the ejected mass of 56Ni to be low (~0.007 Msun). The SN explosion energy appears to have been small, similar to SN 2005cs. SN 2009js i...

  18. Stochasticity and efficiency of convection-dominated vs. SASI-dominated supernova explosions

    CERN Document Server

    Cardall, Christian Y

    2015-01-01

    We present an initial report on 160 simulations of a highly simplified model of the post-bounce supernova environment in three spatial dimensions (3D). We set different values of a parameter characterizing the impact of nuclear dissociation at the stalled shock in order to regulate the post-shock fluid velocity, thereby determining the relative importance of convection and the stationary accretion shock instability (SASI). While our convection-dominated runs comport with the paradigmatic notion of a `critical neutrino luminosity' for explosion at a given mass accretion rate (albeit with a nontrivial spread in explosion times just above threshold), the outcomes of our SASI-dominated runs are much more stochastic: a sharp threshold critical luminosity is `smeared out' into a rising probability of explosion over a $\\sim 20\\%$ range of luminosity. We also find that the SASI-dominated models are able to explode with 3 to 4 times less efficient neutrino heating, indicating that progenitor properties, and fluid and ...

  19. Type Ia Supernova Explosions from Hybrid Carbon-Oxygen-Neon White Dwarf Progenitors

    CERN Document Server

    Willcox, Donald E; Calder, Alan C; Denissenkov, Pavel A; Herwig, Falk

    2016-01-01

    Motivated by recent results in stellar evolution that predict the existence of hybrid white dwarf (WD) stars with a C-O core inside an O-Ne shell, we simulate thermonuclear (Type Ia) supernovae from these hybrid progenitors. We use the FLASH code to perform multidimensional simulations in the deflagration to detonation transition (DDT) explosion paradigm. Our hybrid progenitor models were produced with the MESA stellar evolution code and include the effects of the Urca process, and we map the progenitor model to the FLASH grid. We performed a suite of DDT simulations over a range of ignition conditions consistent with the progenitor's thermal and convective structure assuming multiple ignition points. To compare the results from these hybrid WD stars to previous results from C-O white dwarfs, we construct a set of C-O WD models with similar properties and similarly simulate a suite of explosions. We find that despite significant variability within each suite, trends distinguishing the explosions are apparent ...

  20. SN~2012cg: Evidence for Interaction Between a Normal Type Ia Supernova and a Non-Degenerate Binary Companion

    CERN Document Server

    Marion, G H; Vinkó, Jozsef; Silverman, Jeffrey M; Sand, David J; Challis, Peter; Kirshner, Robert P; Wheeler, J Craig; Berlind, Perry; Brown, Warren R; Calkins, Michael L; Dhungana, Govinda; Foley, Ryan J; Friedman, Andrew S; Graham, Melissa L; Howell, D Andrew; Hsiao, Eric Y; Irwin, Jonathan M; Kehoe, Robert; Macri, Lucas M; Mandel, Kaisey; McCully, Curtis; Rines, Kenneth J; Wilhelmy, Steven; Zheng, Weikang

    2015-01-01

    We report evidence for excess blue light from the Type Ia supernova SN~2012cg at fifteen and sixteen days before maximum B-band brightness. The emission is consistent with predictions for the impact of the supernova on a non-degenerate binary companion. This is the first evidence for emission from a companion to a normal SN~Ia. Sixteen days before maximum light, the B-V color of SN~2012cg is 0.2 mag bluer than for other normal SN~Ia. At later times, this supernova has a typical SN~Ia light curve, with extinction-corrected M_B = -19.62 \\pm 0.02 mag and Delta m_{15}(B) = 0.86 \\pm 0.02. Our data set is extensive, with photometry in 7 filters from 5 independent sources. Early spectra also show the effects of blue light, and high-velocity features are observed at early times. Near maximum, the spectra are normal with a silicon velocity v_{Si} = -10,500 km/s. Comparing the early data with models by Kasen (2010) favors a main-sequence companion of about 6 solar masses. It is possible that many other SN Ia have main-...

  1. Explosion of red-supergiant stars: Influence of the atmospheric structure on shock breakout and early-time supernova radiation

    Science.gov (United States)

    Dessart, Luc; John Hillier, D.; Audit, Edouard

    2017-09-01

    Early-time observations of Type II supernovae (SNe) 2013cu and 2013fs have revealed an interaction of ejecta with material near the star surface. Unlike Type IIn SN 2010jl, which interacts with a dense wind for 1 yr, the interaction ebbs after 2-3 d, suggesting a dense and compact circumstellar envelope. Here, we use multi-group radiation hydrodynamics and non-local-thermodynamic-equilibrium radiative transfer to explore the properties of red-supergiant (RSG) star explosions embedded in a variety of dense envelopes. We consider the cases of an extended static atmosphere or a steady-state wind, adopting a range of mass loss rates. The shock breakout signal, luminosity and color evolution up to 10 d, and ejecta dynamics are strongly influenced by the properties of this nearby environment. This compromises the use of early-time observations to constrain R⋆. For dense circumstellar envelopes, the time-integrated luminosity over the first 10-15 d can be boosted by a factor of a few. The presence of narrow lines for 2-3 d in 2013fs and 2013cu require a cocoon of material of 0.01 M⊙ out to 5-10 R⋆. Spectral lines evolve from electron scattering to Doppler broadened with a growing blueshift of their emission peaks. Recent studies propose a super-wind phase with a mass loss rate from 0.001 up to 1 M⊙ yr-1 in the last months or years of the life of a RSG, although there is no observational constraint that this external material is a steady-state outflow. Alternatively, observations may be explained by the explosion of a RSG star inside its complex atmosphere. Indeed, spatially resolved observations reveal that RSG stars have extended atmospheres, with the presence of downflows and upflows out to several R⋆, even in a standard RSG such as Betelgeuse. Mass loading in the region intermediate between star and wind can accommodate the 0.01 M⊙ needed to explain the observations of 2013fs. Signatures of interaction in early-time spectra of RSG star explosions may

  2. 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.

  3. SN 2010j1: Optical to Hard X-Ray Observations Reveal an Explosion Embedded in a Ten Solar Mass Cocoon

    Science.gov (United States)

    Ofek, Eran; Zoglauer, Andreas; Boggs, Steven E.; Barriere, Nicolas M.; Reynolds, Stephen P.; Fryer, Chris L.; Harrison, Fiona A.; Cenko, S. Bradley; Kulkarni, Shrinivas R.; Zhang, William W.; Kulkarni, Shrinivas R.; Gal-Yam, Avishay; Arcavi, Iair; Bellm, Eric; Bloom, Joshua S.; Christensen, Finn; Craig, William W.; Even, Wesley; Filippenko, Alexei V.; Grefenstette, Brian; Hailey, Charles J.; Laher, Russ; Madsen, Kristin; Nakar, Ehud; Nugent, Peter E.; Stern, Daniel; Sullivan, Mark; Surace, Jason; Zhang, William W.

    2014-01-01

    Some supernovae (SNe) may be powered by the interaction of the SN ejecta with a large amount of circumstellar matter (CSM). However, quantitative estimates of the CSM mass around such SNe are missing when the CSM material is optically thick. Specifically, current estimators are sensitive to uncertainties regarding the CSM density profile and the ejecta velocity. Here we outline a method to measure the mass of the optically thick CSM around such SNe. We present new visible-light and X-ray observations of SN 2010jl (PTF 10aaxf), including the first detection of an SN in the hard X-ray band using NuSTAR. The total radiated luminosity of SN 2010jl is extreme atleast 9 1050 erg. By modeling the visible-light data, we robustly show that the mass of the circumstellar material within 1016 cm of the progenitor of SN 2010jl was in excess of 10M_. This mass was likely ejected tens of years prior to the SN explosion. Our modeling suggests that the shock velocity during shock breakout was 6000 km s1, decelerating to 2600 km s1 about 2 yr after maximum light. Furthermore, our late-time NuSTAR and XMM spectra of the SN presumably provide the first direct measurement of SN shock velocity 2 yr after the SN maximum light measured to be in the range of 2000-4500 km s1 if the ions and electrons are in equilibrium, and_2000 km s1 if they are not in equilibrium. This measurement is in agreement with the shock velocity predicted by our modeling of the visible-light data. Our observations also show that the average radial density distribution of the CSM roughly follows an r2 law. A possible explanation for the _10M_ of CSM and the wind-like profile is that they are the result of multiple pulsational pair instability events prior to the SN explosion, separated from each other by years.

  4. SALT spectroscopic classification of PS16atu (SN 2016atv) as a type-Ia supernova after maximum light

    Science.gov (United States)

    Jha, S. W.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Kotze, M.

    2016-03-01

    We obtained SALT (+RSS) spectroscopy of PS16atu (SN 2016atv) on 2016 Mar 10.1 UT, covering the wavelength range 350-920 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS16atu is a type-Ia supernova approximately a week past maximum light.

  5. Light Curves of Core-Collapse Supernovae with Substantial Mass Loss using the New Open-Source SuperNova Explosion Code (SNEC)

    CERN Document Server

    Morozova, V; Renzo, M; Ott, C D; Clausen, D; Couch, S M; Ellis, J; Roberts, L F

    2015-01-01

    We present the SuperNova Explosion Code SNEC, an open-source Lagrangian code for the hydrodynamics and equilibrium-diffusion radiation transport in the expanding envelopes of supernovae. Given a model of a progenitor star, an explosion energy, and an amount and distribution of radioactive nickel, SNEC generates the bolometric light curve, as well as the light curves in different wavelength bands assuming black body emission. As a first application of SNEC, we consider the explosions of a grid of 15 Msun (at zero-age main sequence) stars whose hydrogen envelopes are stripped to different extents and at different points in their evolution. The resulting light curves exhibit plateaus with durations of ~20-100 days if >~1.5-2 Msun of hydrogen-rich material is left and no plateau if less hydrogen-rich material is left. The shorter plateau lengths are unlike the Type IIP supernova light curves typically observed in nature. This suggests that, at least for zero-age main sequence masses <~ 20 Msun, hydrogen mass l...

  6. SN 2010jl: Optical to Hard X-ray Observations Reveal an Explosion Embedded In a Ten Solar Mass Cocoon

    DEFF Research Database (Denmark)

    Ofek, Eran O.; Zoglauer, Andreas; Boggs, Steven E.

    2014-01-01

    explosion. Our modeling suggests that the shock velocity during shock breakout was ~6000 km s-1, decelerating to ~2600 km s-1 about 2 yr after maximum light. Furthermore, our late-time NuSTAR and XMM spectra of the SN presumably provide the first direct measurement of SN shock velocity 2 yr after the SN...... that the average radial density distribution of the CSM roughly follows an r-2 law. A possible explanation for the ≳ 10 M⊙ of CSM and the wind-like profile is that they are the result of multiple pulsational pair instability events prior to the SN explosion, separated from each other by years....

  7. A possible mechanism for over luminous type Ia supernovae explosions inspired by dark matter

    CERN Document Server

    Jing, Zhenzhen; Wen, Dehua

    2016-01-01

    Dark matter is believed to be a major component of our universe. In this paper we propose a new mechanism based on dark matter inspired super-Chandrasekhar mass white dwarf to explain the recent observation of super luminous type Ia supernovae explosions. Our calculation shows when a white dwarf accretes enough dark matter, due to the Pauli exclusive principle between fermionic dark matter particles, the mass of corresponding dark white dwarf (which means the white dwarf mixed with dark matters) can significantly exceeds the Chandrasekhar limit. Moreover, we investigate some physical observable quantities, such as the redshift and moment of inertia of the dark white dwarf and found that these quantities are sensitive to the dark matter particle's distributions and thus can be potentially used to probe the relevant information of dark matter particles in the future.

  8. Recurring X-ray Outbursts in the Supernova Impostor SN~2010da in NGC~300

    CERN Document Server

    Binder, B; Kong, A K H; Gaetz, T J; Plucinsky, P P; Skillman, E D; Dolphin, A

    2016-01-01

    We present new observations of the "supernova impostor" SN 2010da using the Chandra X-ray Observatory and the Hubble Space Telescope. During the initial 2010 outburst, the 0.3-10 keV luminosity was observed by Swift to be $\\sim5\\times10^{38}$ erg s$^{-1}$ and faded by a factor of $\\sim$25 in a four month period. Our two new Chandra observations show a factor of $\\sim$10 increase in the 0.35-8 keV X-ray flux, from $\\sim$4$\\times10^{36}$ erg s$^{-1}$ to $4\\times10^{37}$ erg s$^{-1}$ in $\\sim$6 months, and the X-ray spectrum is consistent in both observations with a power law photon index of $\\Gamma\\sim0$. We find evidence of X-ray spectral state changes: when SN 2010da is in a high-luminosity state, the X-ray spectrum is harder ($\\Gamma\\sim0$) compared to the low-luminosity state ($\\Gamma\\sim1.2\\pm0.8$). Using our Hubble observations, we fit the color magnitude diagram of the coeval stellar population to estimate a time since formation of the SN 2010da progenitor system of $\\lesssim$5 Myr. Our observations are ...

  9. SN 2012aa - a transient between Type Ibc core-collapse and superluminous supernovae

    CERN Document Server

    Roy, R; Silverman, J M; Pastorello, A; Fransson, C; Drake, A; Taddia, F; Fremling, C; Kankare, E; Kumar, B; Cappellaro, E; Bose, S; Benetti, S; Filippenko, A V; Valenti, S; Nyholm, A; Ergon, M; Sutaria, F; Kumar, B; Pandey, S B; Nicholl, M; Garcia-Alvarez, D; Tomasella, L; Karamehmetoglu, E; Migotto, K

    2016-01-01

    Context: Research on supernovae (SNe) over the past decade has confirmed that there is a distinct class of events which are much more luminous (by $\\sim2$ mag) than canonical core-collapse SNe (CCSNe). These events with visual peak magnitudes $\\lesssim-21$ are called superluminous SNe (SLSNe). Aims: There are a few intermediate events which have luminosities between these two classes. Here we study one such object, SN 2012aa. Methods: The optical photometric and spectroscopic follow-up observations of the event were conducted over a time span of about 120 days. Results: With V_abs at peak ~-20 mag, the SN is an intermediate-luminosity transient between regular SNe Ibc and SLSNe. It also exhibits an unusual secondary bump after the maximum in its light curve. We interpret this as a manifestation of SN-shock interaction with the CSM. If we would assume a $^{56}$Ni-powered ejecta, the bolometric light curve requires roughly 1.3 M_sun of $^{56}$Ni and an ejected mass of ~14 M_sun. This would also imply a high kin...

  10. An Arabic report about supernova SN 1006 by Ibn Sīnā (Avicenna)

    Science.gov (United States)

    Neuhäuser, R.; Ehrig-Eggert, C.; Kunitzsch, P.

    2017-01-01

    We present here an Arabic report about supernova 1006 (SN 1006) written by the famous Persian scholar Ibn Sina (Lat. Avicenna, AD 980-1037), which was not discussed in astronomical literature before. The short observational report about a new star is part of Ibn Sina's book called al-Shifa', a work about philosophy including physics, astronomy, and meteorology. We present the Arabic text and our English translation. After a detailed discussion of the dating of the observation, we show that the text specifies that the transient celestial object was stationary and/or tail-less ("a star among the stars"), that it "remained for close to three months getting fainter and fainter until it disappeared", that it "threw out sparks", i.e. it was scintillating and very bright, and that the color changed with time. The information content is consistent with the other Arabic and non-Arabic reports about SN 1006. Hence, it is quite clear that Ibn Sina refers to SN 1006 in his report, given as an example for transient celestial objects in a discussion of Aristotle's "Meteorology". Given the wording and the description, e.g. for the color evolution, this report is independent from other reports known so far.

  11. An Arabic report about supernova SN 1006 by Ibn Sina (Avicenna)

    CERN Document Server

    Neuhaeuser, Ralph; Kunitzsch, Paul

    2016-01-01

    We present here an Arabic report about supernova 1006 (SN 1006) written by the famous Arabic scholar Ibn Sina (Lat. Avicenna, AD 980-1037), which was not discussed in astronomical literature before. The short observational report about a new star is part of Ibn Sina's book called al-Shifa', a work about philosophy including physics, astronomy, and meteorology. We present the Arabic text and our English translation. After a detailed discussion of the dating of the observation, we show that the text specifies that the transient celestial object was stationary and/or tail-less ("a star among the stars"), that it "remained for close to three months getting fainter and fainter until it disappeared", that it "threw out sparks", i.e. it was scintillating and very bright, and that the color changed with time. The information content is consistent with the other Arabic and non-Arabic reports about SN 1006. Hence, it is quite clear that Ibn Sina refers to SN 1006 in his report, given as an example for transient celesti...

  12. The Oxygen Features in Type Ia Supernovae and the Implications for the Nature of Thermonuclear Explosions

    CERN Document Server

    Zhao, Xulin; Wang, Xiaofeng; Wang, Lifan; Sai, Hanna; Zhang, Jujia; Zhang, Tianmeng; Huang, Fang; Rui, Liming

    2016-01-01

    The absorption feature O I 7773 is an important spectral indicator for type Ia supernovae (SNe~Ia) that can be used to trace the unburned material at outer layers of the exploding white dwarf. In this work, we use a large sample of SNe~Ia to examine this absorption at early phases (i.e., -13 days explosive oxygen burning occurs at the outermost layer of supernova and difference in burning there could lead to the observed diversity, which are in ...

  13. Curvas de luz de supernovas ricas en hidrógeno

    Science.gov (United States)

    Rojas Kaufmann, M. L.; Bersten, M.

    2016-08-01

    Type II supernovae (SNe II) are the most common type of explosions in the Universe. There is a small and peculiar subgroup of those objects that show light curves similar to the famous SN 1987A. In this work we present an analysis of how the variation of certain physical parameters such as the mass and radius of the progenitor star, the energy of the explosion and the amount of radioactive material impact on the light curve of these objects, based on models that simulate the stellar explosions. In particular, we analyze the case of SN 2009mw, one of the few supernovae with similar characteristics to the SN 1987A.

  14. 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

  15. Type Ia Supernova Rate Measurements to Redshift 2.5 from CANDELS : Searching for Prompt Explosions in the Early Universe

    CERN Document Server

    Rodney, Steven A; Strolger, Louis-Gregory; Dahlen, Tomas; Graur, Or; Casertano, Stefano; Dickinson, Mark E; Ferguson, Henry C; Garnavich, Peter; Hayden, Brian; Jha, Saurabh W; Jones, David O; Kirshner, Robert P; Koekemoer, Anton M; McCully, Curtis; Mobasher, Bahram; Patel, Brandon; Weiner, Benjamin J; Cenko, Bradley S; Clubb, Kelsey I; Cooper, Michael; Filippenko, Alexei V; Frederiksen, Teddy F; Hjorth, Jens; Leibundgut, Bruno; Matheson, Thomas; Nayyeri, Hooshang; Penner, Kyle; Trump, Jonathan; Silverman, Jeffrey M; U, Vivian; Bostroem, K Azalee; Challis, Peter; Rajan, Abhijith; Wolff, Schuyler; Faber, S M; Grogin, Norman A; Kocevski, Dale

    2014-01-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) was a multi-cycle treasury program on the Hubble Space Telescope (HST) that surveyed a total area of ~0.25 deg^2 with ~900 HST orbits spread across 5 fields over 3 years. Within these survey images we discovered 65 supernovae (SN) of all types, out to z~2.5. We classify ~24 of these as Type Ia SN (SN Ia) based on host galaxy redshifts and SN photometry (supplemented by grism spectroscopy of 6 SN). Here we present a measurement of the volumetric SN Ia rate as a function of redshift, reaching for the first time beyond z=2 and putting new constraints on SN Ia progenitor models. Our highest redshift bin includes detections of SN that exploded when the universe was only ~3 Gyr old and near the peak of the cosmic star formation history. This gives the CANDELS high redshift sample unique leverage for evaluating the fraction of SN Ia that explode promptly after formation (40 Myr. However, a mild tension is apparent between ground-based low-z...

  16. THE CRITICAL MASS RATIO OF DOUBLE WHITE DWARF BINARIES FOR VIOLENT MERGER-INDUCED TYPE IA SUPERNOVA EXPLOSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yushi [Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Nakasato, Naohito [Department of Computer Science and Engineering, University of Aizu, Tsuruga Ikki-machi Aizu-Wakamatsu, Fukushima 965-8580 (Japan); Tanikawa, Ataru; Hachisu, Izumi [Department of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Nomoto, Ken’ichi [Kavli Institute for the Physics and Mathematics of the universe (WPI), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Maeda, Keiichi, E-mail: sato@ea.c.u-tokyo.ac.jp [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)

    2016-04-10

    Mergers of carbon–oxygen (CO) white dwarfs (WDs) are considered to be one of the potential progenitors of type Ia supernovae (SNe Ia). Recent hydrodynamical simulations showed that the less massive (secondary) WD violently accretes onto the more massive (primary) one, carbon detonation occurs, the detonation wave propagates through the primary, and the primary finally explodes as a sub-Chandrasekhar mass SN Ia. Such an explosion mechanism is called the violent merger scenario. Based on the smoothed particle hydrodynamics simulations of merging CO WDs, we derived a critical mass ratio (q{sub cr}) leading to the violent merger scenario that is more stringent than previous results. We conclude that this difference mainly comes from the differences in the initial condition of whether or not the WDs are synchronously spinning. Using our new results, we estimated the brightness distribution of SNe Ia in the violent merger scenario and compared it with previous studies. We found that our new q{sub cr} does not significantly affect the brightness distribution. We present the direct outcome immediately following CO WD mergers for various primary masses and mass ratios. We also discussed the final fate of the central system of the bipolar planetary nebula Henize 2-428, which was recently suggested to be a double CO WD system whose total mass exceeds the Chandrasekhar-limiting mass, merging within the Hubble time. Even considering the uncertainties in the proposed binary parameters, we concluded that the final fate of this system is almost certainly a sub-Chandrasekhar mass SN Ia in the violent merger scenario.

  17. Chandra and ASCA X-ray Observations of the Radio Supernova SN1979C IN NGC 4321

    CERN Document Server

    Ray, A; Schlegel, E M

    2001-01-01

    We report on the X-ray observation of the radio selected supernova SN1979C carried out with ASCA in 1997 December and serendipitously available from a Chandra Guaranteed Time Observation in 1999 November. The supernova, of type SN II-Linear (SN IIL), was first observed in the optical and occurred in the weakly barred, almost face on spiral galaxy NGC 4321 (M100). The galaxy, a member of the Virgo S cluster, is at a distance of 17.1 Mpc, and contains at least three other supernovae discovered in this century. The useful exposure time was ~25 ks for the Solid-State Imaging Spectrometer (SIS), ~28 ks for the Gas Scintillation Imaging Spectrometer (GIS), and ~2.5 ks for Chandra's Advanced CCD Imaging Spectrometer (ACIS). No point source was detected at the radio position of SN1979C in a 3' diameter half power response circle in the ASCA data. The background and galaxy subtracted SN signal had a 3sigma upper limit to the flux of 6.3x10^-14 ergs/s/cm^-2 in the full ASCA SIS band (0.4-10.0 keV) and a 3sigma upper li...

  18. Photometric and spectroscopic observations, and abundance tomography modelling of the type Ia supernova SN 2014J located in M82

    CERN Document Server

    Ashall, C; Bersier, D; Hachinger, S; Phillips, M; Percival, S; James, P; Maguire, K

    2014-01-01

    Spectroscopic and photometric observations of the nearby Type Ia Supernova (SN Ia) SN 2014J are presented. Spectroscopic observations were taken -8 to +10 d relative to $B$-band maximum, using FRODOSpec, a multi-purpose integral-field unit spectrograph. The observations range from 3900 \\AA\\ to 9000 \\AA. SN 2014J is located in M82 which makes it the closest SN Ia studied in at least the last 28 years. It is a spectrosopically normal SN Ia with high velocity features. We model the spectra of SN 2014J with a Monte Carlo (MC) radiative transfer code, using the abundance tomography technique. SN 2014J is highly reddened, with a host galaxy extinction of ${E(B-V)}$=1.2 (R$_{V}$=1.38). It has a Delta m_{15}(B) of 1.08$\\pm$0.03 when corrected for extinction. As SN 2014J is a normal SN Ia, the density structure of the classical W7 model was selected. The model and photometric luminosities are both consistent with $B$-band maximum occurring on JD 2456690.4$\\pm$0.12. The abundance of the SN 2014J behaves like other norm...

  19. A supernova feedback implementation for the astrophysical simulation software Arepo

    CERN Document Server

    Bubel, André-Patrick

    2016-01-01

    Supernova (SN) explosions play an important role in the development of galactic structures. The energy and momentum imparted on the interstellar medium (ISM) in so called "supernova feedback" drives turbulence, heats the gas, enriches it with heavy elements, can lead to the formation of new stars or even suppress star formation by disrupting stellar nurseries. In the numerical simulation at the sub-galactic level, not including the energy and momentum of supernovas in the physical description of the problem can also lead to several problems that might partially be resolved by including a description of supernovas. In this thesis such an implementation is attempted for the combined numerical hydrodynamics and N-body simulation software Arepo (Springel, 2010). In a stochastic process a large amount of thermal energy is imparted on a number of neighbouring cells, mimicking the effect of a supernova explosions. We test this approach by modelling the explosion of a single supernova in a uniform density medium and ...

  20. The Broad-Lined Type Ic SN 2012ap and the Nature of Relativistic Supernovae Lacking a Gamma-Ray Burst Detection

    Science.gov (United States)

    Milisavljevic, D.; Margutti, R.; Parrent, J. T.; Soderberg, A. M.; Fesen, R. A.; Mazzali, P.; Maeda, K.; Sanders, N. E.; Cenko, S. B.; Silverman, J. M.

    2014-01-01

    We present ultraviolet, optical, and near-infrared observations of SN2012ap, a broad-lined Type Ic supernova in the galaxy NGC 1729 that produced a relativistic and rapidly decelerating outflow without a gamma-ray burst signature. Photometry and spectroscopy follow the flux evolution from -13 to +272 days past the B-band maximum of -17.4 +/- 0.5 mag. The spectra are dominated by Fe II, O I, and Ca II absorption lines at ejecta velocities of v approx. 20,000 km s(exp. -1) that change slowly over time. Other spectral absorption lines are consistent with contributions from photospheric He I, and hydrogen may also be present at higher velocities (v approx. greater than 27,000 km s(exp. -1)). We use these observations to estimate explosion properties and derive a total ejecta mass of 2.7 Solar mass, a kinetic energy of 1.0×1052 erg, and a (56)Ni mass of 0.1-0.2 Solar mass. Nebular spectra (t > 200 d) exhibit an asymmetric double-peaked [O I] lambda lambda 6300, 6364 emission profile that we associate with absorption in the supernova interior, although toroidal ejecta geometry is an alternative explanation. SN2012ap joins SN2009bb as another exceptional supernova that shows evidence for a central engine (e.g., black-hole accretion or magnetar) capable of launching a non-negligible portion of ejecta to relativistic velocities without a coincident gamma-ray burst detection. Defining attributes of their progenitor systems may be related to notable properties including above-average environmental metallicities of Z approx. greater than Solar Z, moderate to high levels of host-galaxy extinction (E(B -V ) > 0.4 mag), detection of high-velocity helium at early epochs, and a high relative flux ratio of [Ca II]/[O I] > 1 at nebular epochs. These events support the notion that jet activity at various energy scales may be present in a wide range of supernovae.

  1. THE BROAD-LINED Type Ic SN 2012ap AND THE NATURE OF RELATIVISTIC SUPERNOVAE LACKING A GAMMA-RAY BURST DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Milisavljevic, D.; Margutti, R.; Parrent, J. T.; Soderberg, A. M.; Sanders, N. E.; Kamble, A.; Chakraborti, S.; Drout, M. R.; Kirshner, R. P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Fesen, R. A. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); Mazzali, P. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5RF (United Kingdom); Maeda, K. [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Silverman, J. M. [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Filippenko, A. V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Pickering, T. E. [Southern African Large Telescope, P.O. Box 9, Observatory 7935, Cape Town (South Africa); Kawabata, K. [Hiroshima Astrophysical Science Center, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Hattori, T. [Subaru Telescope, National Astronomical Observatory of Japan, Hilo, HI 96720 (United States); Hsiao, E. Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Stritzinger, M. D., E-mail: dmilisav@cfa.harvard.edu [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, DK-8000 Aarhus C (Denmark); and others

    2015-01-20

    We present ultraviolet, optical, and near-infrared observations of SN 2012ap, a broad-lined Type Ic supernova in the galaxy NGC 1729 that produced a relativistic and rapidly decelerating outflow without a gamma-ray burst signature. Photometry and spectroscopy follow the flux evolution from –13 to +272 days past the B-band maximum of –17.4 ± 0.5 mag. The spectra are dominated by Fe II, O I, and Ca II absorption lines at ejecta velocities of v ≈ 20,000 km s{sup –1} that change slowly over time. Other spectral absorption lines are consistent with contributions from photospheric He I, and hydrogen may also be present at higher velocities (v ≳ 27,000 km s{sup –1}). We use these observations to estimate explosion properties and derive a total ejecta mass of ∼2.7 M {sub ☉}, a kinetic energy of ∼1.0 × 10{sup 52} erg, and a {sup 56}Ni mass of 0.1-0.2 M {sub ☉}. Nebular spectra (t > 200 days) exhibit an asymmetric double-peaked [O I] λλ6300, 6364 emission profile that we associate with absorption in the supernova interior, although toroidal ejecta geometry is an alternative explanation. SN 2012ap joins SN 2009bb as another exceptional supernova that shows evidence for a central engine (e.g., black hole accretion or magnetar) capable of launching a non-negligible portion of ejecta to relativistic velocities without a coincident gamma-ray burst detection. Defining attributes of their progenitor systems may be related to notable observed properties including environmental metallicities of Z ≳ Z {sub ☉}, moderate to high levels of host galaxy extinction (E(B – V) > 0.4 mag), detection of high-velocity helium at early epochs, and a high relative flux ratio of [Ca II]/[O I] >1 at nebular epochs. These events support the notion that jet activity at various energy scales may be present in a wide range of supernovae.

  2. A Neutrino-Driven Core Collapse Supernova Explosion of a 15 M Star

    CERN Document Server

    Mezzacappa, Anthony; Bruenn, Stephen W; Hix, W Raphael; Messer, O E Bronson; Endeve, Eirik; Blondin, John M; Harris, J Austin; Marronetti, Pedro; Yakunin, Konstantin N; Lingerfelt, Eric J

    2015-01-01

    We present results from an ab initio three-dimensional, multi-physics core collapse supernova simulation for the case of a 15 M progenitor. Our simulation includes multi-frequency neutrino transport with state-of-the-art neutrino interactions in the "ray-by-ray" approximation, and approximate general relativity. Our model exhibits a neutrino-driven explosion. The shock radius begins an outward trajectory at approximately 275 ms after bounce, giving the first indication of a developing explosion in the model. The onset of this shock expansion is delayed relative to our two-dimensional counterpart model, which begins at approximately 200 ms after core bounce. At a time of 441 ms after bounce, the angle-averaged shock radius in our three-dimensional model has reached 751 km. Further quantitative analysis of the outcomes in this model must await further development of the post-bounce dynamics and a simulation that will extend well beyond 1 s after stellar core bounce, based on the results for the same progenitor ...

  3. OGLE-2013-SN-079: A LONELY SUPERNOVA CONSISTENT WITH A HELIUM SHELL DETONATION

    Energy Technology Data Exchange (ETDEWEB)

    Inserra, C.; Sim, S. A.; Smartt, S. J.; Nicholl, M.; Jerkstrand, A.; Chen, T.-W. [Astrophysics Research Centre, School of Mathematics and Physics, Queens University Belfast, Belfast BT7 1NN (United Kingdom); Wyrzykowski, L. [University of Warsaw, Astronomical Observatory, Al. Ujazdowskie 400-478 Warszawa (Poland); Fraser, M.; Blagorodnova, N.; Campbell, H. [Institute of Astronomy, University of Cambridge, Madingley Road, CB3 0HA Cambridge (United Kingdom); Shen, K. J. [Department of Astronomy and Theoretical Astrophysics Center, University of California, Berkeley, CA 94720 (United States); Gal-Yam, A. [Benoziyo Center for Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel); Howell, D. A.; Valenti, S. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102 Goleta, CA 93117 (United States); Maguire, K. [European Southern Observatory for Astronomical Research in the Southern Hemisphere (ESO), Karl-Schwarzschild-Str. 2, 85748 Garching b. Munchen (Germany); Mazzali, P.; Bersier, D. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool (United Kingdom); Taubenberger, S.; Benitez-Herrera, S. [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching (Germany); Elias-Rosa, N., E-mail: c.inserra@qub.ac.uk [INAF - Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); and others

    2015-01-20

    We present observational data for a peculiar supernova discovered by the OGLE-IV survey and followed by the Public ESO Spectroscopic Survey for Transient Objects. The inferred redshift of z = 0.07 implies an absolute magnitude in the rest-frame I-band of M{sub I} ∼ –17.6 mag. This places it in the luminosity range between normal Type Ia SNe and novae. Optical and near infrared spectroscopy reveal mostly Ti and Ca lines, and an unusually red color arising from strong depression of flux at rest wavelengths <5000 Å. To date, this is the only reported SN showing Ti-dominated spectra. The data are broadly consistent with existing models for the pure detonation of a helium shell around a low-mass CO white dwarf and ''double-detonation'' models that include a secondary detonation of a CO core following a primary detonation in an overlying helium shell.

  4. The diffuse supernova neutrino background: Expectations and uncertainties derived from SN1987A

    CERN Document Server

    Vissani, Francesco

    2011-01-01

    Context: The detection of the diffuse supernova neutrino background may be imminent, but theoretical predictions are affected by substantial uncertainties. AIMS. We calculate the signal and its uncertainty with the present configuration of Super-Kamiokande and consider the possibility of lowering the threshold by means of gadolinium loading. Methods: We model neutrino emission following the analysis of SN1987A by Pagliaroli and collaborators 2009 and use the number of expected events in the neutrino detector as a free parameter of the fit. The best-fit value of this parameter and its error are evaluated by means of standard maximum likelihood procedures, taking into account properly the correlations. Results: The uncertainties in the astrophysics of the emission dominates the total uncertainty in the expected signal rate, which conservatively ranges from 0.3 to 0.9 events per year and from 1.1 to 2.9 with gadolinium.

  5. The radio evolution of supernova SN$\\,$2008iz in M$\\,$82

    CERN Document Server

    Kimani, N; Brunthaler, A; Menten, K M; Martí-Vidal, I; Henkel, C; Falcke, H; Muxlow, T W B; Beswick, R J; Bower, G C

    2016-01-01

    We report on multi-frequency Very Large Array (VLA) and Very Long Baseline Interferometry (VLBI) radio observations for a monitoring campaign of supernova SN$\\,$2008iz in the nearby irregular galaxy M$\\,$82. We fit two models to the data, a simple time power-law, S$\\propto$ t$^\\beta$, and a simplified Weiler model, yielding decline indices, $\\beta$ of -1.22$\\pm$0.07 (days 100-1500) and -1.41$\\pm$0.02 (days 76-2167), respectively. The late-time radio light curve evolution shows flux-density flares at $\\sim\\,$970 and $\\sim\\,$1400 days which are a factor of $\\sim\\,$2 and $\\sim\\,$4 higher than the expected flux, respectively. The later flare, besides being brighter, does not show signs of decline at least from results examined so far (2014 January 23, day 2167). We derive the spectral index, $\\alpha$, S$\\propto$ $\

  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. Solar abundance of manganese: a case for the existence of near Chandrasekhar-mass Type Ia supernova progenitors

    CERN Document Server

    Seitenzahl, Ivo R; Roepke, Friedrich K; Ruiter, Ashley J

    2013-01-01

    Context: Manganese is predominantly synthesised in Type Ia supernova (SN Ia) explosions. Owing to the entropy dependence of the Mn yield in explosive thermonuclear burning, SNe Ia involving near Chandrasekhar-mass white dwarfs (WDs) are predicted to produce Mn to Fe ratios significantly exceeding those of SN Ia explosions involving sub-Chandrasekhar mass primary WDs. Of all current supernova explosion models, only SN Ia models involving near-Chandrasekhar mass WDs produce [Mn/Fe] > 0.0. Aims: Using the specific yields for competing SN Ia scenarios, we aim to constrain the relative fractions of exploding near-Chandrasekhar mass to sub-Chandrasekhar mass primary WDs in the Galaxy. Methods: We extract the Mn yields from three-dimensional thermonuclear supernova simulations referring to different initial setups and progenitor channels. We then compute the chemical evolution of Mn in the Solar neighborhood, assuming SNe Ia are made up of different relative fractions of the considered explosion models. Results: We ...

  8. The Blast-Wave-Driven Instability as a Vehicle for Understanding Supernova Explosion Structure

    Energy Technology Data Exchange (ETDEWEB)

    Miles, A R

    2008-05-27

    Blast-wave-driven instabilities play a rich and varied role throughout the evolution of supernovae from explosion to remnant, but interpreting their role is difficult due to the enormous complexity of the stellar systems. We consider the simpler and fundamental hydrodynamic instability problem of a material interface between two constant-density fluids perturbed from spherical and driven by a divergent central Taylor-Sedov blast wave. The existence of unified solutions at high Mach number and small density ratio suggests that general conclusions can be drawn about the likely asymptotic structure of the mixing zone. To this end we apply buoyancy-drag and bubble merger models modified to include the effects of divergence and radial velocity gradients. In general, these effects preclude the true self-similar evolution of classical Raleigh-Taylor, but can be incorporated into a quasi-self-similar growth picture. Loss of memory of initial conditions can occur in the quasi-self-similar model, but requires initial mode numbers higher than those predicted for pre-explosion interfaces in Type II SNe, suggesting that their late-time structure is likely strongly influenced by details of the initial perturbations. Where low-modes are dominant, as in the Type Ia Tycho remnant, they result from initial perturbations rather than generation from smaller scales. Therefore, structure observed now contains direct information about the explosion process. When large-amplitude modes are present in the initial conditions, the contribution to the perturbation growth from the Richtmyer-Meshkov instability is significant or dominant compared to Rayleigh-Taylor. Such Richtmyer-Meshkov growth can yield proximity of the forward shock to the growing spikes and structure that strongly resembles that observed in the Tycho. Laser-driven high-energy-density laboratory experiments offer a promising avenue for testing model and simulation descriptions of blast-wave-driven instabilities and making

  9. SN REFSDAL: PHOTOMETRY AND TIME DELAY MEASUREMENTS OF THE FIRST EINSTEIN CROSS SUPERNOVA

    Energy Technology Data Exchange (ETDEWEB)

    Rodney, S. A. [Department of Physics and Astronomy, University of South Carolina, 712 Main St., Columbia, SC 29208 (United States); Strolger, L.-G.; Brammer, G. [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States); Kelly, P. L.; Filippenko, A. V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Bradač, M. [University of California Davis, 1 Shields Avenue, Davis, CA 95616 (United States); Foley, R. J. [Department of Physics, University of Illinois at Urbana-Champaign, 1110 W. Green Street, Urbana, IL 61801 (United States); Graur, O. [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States); Hjorth, J.; Selsing, J. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Jha, S. W. [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); McCully, C. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Dr., Suite 102, Goleta, California 93117 (United States); Molino, A. [Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, Cidade Universitária, 05508-090, São Paulo (Brazil); Riess, A. G. [Department of Physics and Astronomy, The Johns Hopkins University, 3400N. Charles St., Baltimore, MD 21218 (United States); Schmidt, K. B. [Department of Physics, University of California, Santa Barbara, CA 93106-9530 (United States); Sharon, K. [Department of Astronomy, University of Michigan, 1085 S. University Avenue, Ann Arbor, MI 48109 (United States); Treu, T. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); and others

    2016-03-20

    We present the first year of Hubble Space Telescope imaging of the unique supernova (SN) “Refsdal,” a gravitationally lensed SN at z = 1.488 ± 0.001 with multiple images behind the galaxy cluster MACS J1149.6+2223. The first four observed images of SN Refsdal (images S1–S4) exhibited a slow rise (over ∼150 days) to reach a broad peak brightness around 2015 April 20. Using a set of light curve templates constructed from SN 1987A-like peculiar Type II SNe, we measure time delays for the four images relative to S1 of 4 ± 4 (for S2), 2 ± 5 (S3), and 24 ± 7 days (S4). The measured magnification ratios relative to S1 are 1.15 ± 0.05 (S2), 1.01 ± 0.04 (S3), and 0.34 ± 0.02 (S4). None of the template light curves fully captures the photometric behavior of SN Refsdal, so we also derive complementary measurements for these parameters using polynomials to represent the intrinsic light curve shape. These more flexible fits deliver fully consistent time delays of 7 ± 2 (S2), 0.6 ± 3 (S3), and 27 ± 8 days (S4). The lensing magnification ratios are similarly consistent, measured as 1.17 ± 0.02 (S2), 1.00 ± 0.01 (S3), and 0.38 ± 0.02 (S4). We compare these measurements against published predictions from lens models, and find that the majority of model predictions are in very good agreement with our measurements. Finally, we discuss avenues for future improvement of time delay measurements—both for SN Refsdal and for other strongly lensed SNe yet to come.

  10. Hubble Space Telescope and Ground-Based Observations of the Type Iax Supernovae SN 2005hk and SN 2008A

    Energy Technology Data Exchange (ETDEWEB)

    McCully, Curtis; Jha, Saurabh W.; Foley, Ryan J.; Chornock, Ryan; Holtzman, Jon A.; Balam, David D.; Branch, David; Filippenko, Alexei V.; Frieman, Joshua; Fynbo, Johan; Galbany, Lluis; Ganeshalingam, Mohan; Garnavich, Peter M.; Graham, Melissa L.; Hsiao, Eric Y.; Leloudas, Giorgos; Leonard, Douglas C.; Li, Weidong; Riess, Adam G.; Sako, Masao; Schneider, Donald P.; Silverman, Jeffrey M.; Sollerman, Jesper; Steele, Thea N.; Thomas, Rollin C.; Wheeler, J. Craig; Zheng, Chen

    2014-04-24

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). Here we focus on late-time observations, where these objects deviate most dramatically from all other SN types. Instead of the dominant nebular emission lines that are observed in other SNe at late phases, spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with ne109 cm–3. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected "infrared catastrophe," a generic feature of SN Ia models. However, our HST photometry of SN 2008A does not match the predictions of an infrared catastrophe. Moreover, our HST observations rule out a "complete deflagration" that fully disrupts the white dwarf for these peculiar SNe, showing no evidence for unburned material at late times. Deflagration explosion models that leave behind a bound remnant can match some of the observed properties of SNe Iax, but no published model is consistent with all of our observations of SNe 2005hk and 2008A.

  11. Light-Echo Spectrum Reveals the Type of Tycho Brahe's 1572 Supernova

    Science.gov (United States)

    Usuda, T.; Krause, O.; Tanaka, M.; Hattori, T.; Goto, M.; Birkmann, S. M.; Nomoto, K.

    2013-01-01

    We successfully obtained the first optical spectra of the faint light echoes around Cassiopeia A and Tycho Brahe's supernova remnants (SNRs) with FOCAS and the Subaru Telescope. We conclude that Cas A and Tycho's SN 1572 belong to the Type IIb and normal Type Ia supernovae, respectively. Light echo spectra are important in order to obtain further insight into the supernova explosion mechanism of Tycho's SN 1572: how the Type Ia explosion actually proceeds, and whether accretion occurs from a companion or by the merging of two white dwarfs. The proximity of the SN 1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. Future light-echo spectra, obtained in different spatial directions of SN 1572, will enable to construct a three-dimensional spectroscopic view of the explosion.

  12. Photometric and Spectroscopic study of a highly reddened type Ia supernova SN 2003hx in NGC 2076

    CERN Document Server

    Misra, Kuntal; Anupama, G C; Pandey, Kavita

    2008-01-01

    We present $UBVRI$ CCD photometry and optical spectra of the type Ia supernova SN 2003hx which appeared in the galaxy NGC 2076, obtained till $\\sim$ 146 days after the epoch of $B$ band maximum. The supernova reached at maximum brightness in $B$ band on JD 245 2893 $\\pm$ 1.0 with an apparent magnitude of 14.92 $\\pm$ 0.01 mag which was estimated by making template fits to the light curves. SN 2003hx is an example of a highly reddened supernova with $E(B-V)$ = 0.56 $\\pm$ 0.23. We estimate $R_v$ = 1.97 $\\pm$ 0.54 which indicates the small size of dust particles as compared to their galactic counterparts. The luminosity decline rate is $\\Delta m_{15}(B)$ = 1.17 $\\pm$ 0.12 mag and the absolute $B$ band magnitude obtained from the luminosity versus decline rate relation (Phillips et al. 1999) is $M^B_{max}$ = -19.20 $\\pm$ 0.18 mag. The peak bolometric luminosity indicates that $\\sim$ 0.66 $M_\\odot$ mass of $^{56}$ Ni was ejected by the supernova. The spectral evolution indicates the supernova to be a normal type Ia...

  13. Exact and approximate expressions of energy generation rates and their impact on the explosion properties of Pair Instability Supernovae

    CERN Document Server

    Takahashi, Koh; Umeda, Hideyuki; Sumiyoshi, Kohsuke; Yamada, Shoichi

    2015-01-01

    Energetics of nuclear reaction is fundamentally important to understand the mechanism of pair instability supernovae (PISNe). Based on the hydrodynamic equations and thermodynamic relations, we derive exact expressions for energy conservation suitable to be solved in simulation. We also show that some formulae commonly used in the literature are obtained as approximations of the exact expressions. We simulate the evolution of very massive stars of ~100-320 Msun with zero- and 1/10 Zsun, and calculate further explosions as PISNe, applying each of the exact and approximate formulae. The calculations demonstrate that the explosion properties of PISN, such as the mass range, the 56Ni yield, and the explosion energy, are significantly affected by applying the different energy generation rates. We discuss how these results affect the estimate of the PISN detection rate, which depends on the theoretical predictions of such explosion properties.

  14. The early phases of the type Iax supernova SN 2011ay

    CERN Document Server

    Szalai, Tamás; Sárneczky, Krisztián; Takáts, Katalin; Benkő, József M; Kelemen, János; Kuli, Zoltán; Silverman, Jeffrey M; Marion, G Howie; Wheeler, J Craig

    2015-01-01

    We present a detailed study of the early phases of the peculiar supernova 2011ay based on BVRI photometry obtained at Konkoly Observatory, Hungary, and optical spectra taken with the Hobby-Eberly Telescope at McDonald Observatory, Texas. The spectral analysis carried out with SYN++ and SYNAPPS confirms that SN 2011ay belongs to the recently defined class of SNe Iax, which is also supported by the properties of its light and color curves. The estimated photospheric temperature around maximum light, T_{phot} ~8,000 K, is lower than in most Type Ia SNe, which results in the appearance of strong Fe II features in the spectra of SN 2011ay, even during the early phases. We also show that strong blending with metal features (those of Ti II, Fe II, Co II) makes the direct analysis of the broad spectral features very difficult, and this may be true for all SNe Iax. We find two alternative spectrum models that both describe the observed spectra adequately, but their photospheric velocities differ by at least 3,000 km/s...

  15. SN 2015bn: a detailed multi-wavelength view of a nearby superluminous supernova

    CERN Document Server

    Nicholl, M; Smartt, S J; Margutti, R; Kamble, A; Alexander, K D; Chen, T -W; Inserra, C; Arcavi, I; Blanchard, P K; Cartier, R; Chambers, K C; Childress, M J; Chornock, R; Cowperthwaite, P S; Drout, M; Flewelling, H A; Fraser, M; Gal-Yam, A; Galbany, L; Harmanen, J; Holoien, T W -S; Hosseinzadeh, G; Howell, D A; Huber, M E; Jerkstrand, A; Kankare, E; Kochanek, C S; Lin, Z -Y; Lunnan, R; Magnier, E A; Maguire, K; McCully, C; McDonald, M; Metzger, B D; Milisavljevic, D; Mitra, A; Reynolds, T; Saario, J; Shappee, B J; Smith, K W; Valenti, S; Villar, V A; Waters, C; Young, D R

    2016-01-01

    We present observations of SN 2015bn (= PS15ae = CSS141223-113342+004332 = MLS150211-113342+004333), a Type I superluminous supernova (SLSN) at $z=0.1136$. As well as being one of the closest SLSNe, it is intrinsically brighter ($M_U\\approx-23.1$) and in a fainter host ($M_B\\approx-16.0$) than other SLSNe at $z\\sim0.1$. We collected the most extensive dataset for an SLSN I to date, including spectroscopy and UV to NIR photometry from $-$50 to +250 d from maximum light. SN 2015bn is a slowly-declining SLSN, but exhibits surprising undulations in the light curve on a timescale of 30-50 d, which are more pronounced in the UV. The spectrum resembles other SLSNe, but our well-sampled data reveal extraordinarily slow evolution except for a rapid transformation between +7 and +30 d. We detect weak features that we tentatively suggest may be hydrogen and helium. At late times, blue colours and a trio of lines around 6000 \\AA\\ seem to distinguish slowly-declining SLSNe from faster ones. We derive physical properties i...

  16. The Broad-Lined Type Ic SN 2012ap and the Nature of Relativistic Supernovae Lacking a Gamma-ray Burst Detection

    CERN Document Server

    Milisavljevic, D; Parrent, J T; Soderberg, A M; Fesen, R A; Mazzali, P; Maeda, K; Sanders, N E; Cenko, S B; Silverman, J M; Filippenko, A V; Kamble, A; Chakraborti, S; Drout, M R; Kirshner, R P; Pickering, T E; Kawabata, K; Hattori, T; Hsiao, E Y; Stritzinger, M D; Marion, G H; Vinko, J; Wheeler, J C

    2014-01-01

    We present ultraviolet, optical, and near-infrared observations of SN 2012ap, a broad-lined Type Ic supernova in the galaxy NGC 1729 that produced a relativistic and rapidly decelerating outflow without a gamma-ray burst signature. Photometry and spectroscopy follow the flux evolution from -13 to +272 days past the B-band maximum of -17.4 +/- 0.5 mag. The spectra are dominated by Fe II, O I, and Ca II absorption lines at ejecta velocities of 20,000 km/s that change slowly over time. Other spectral absorption lines are consistent with contributions from photospheric He I, and hydrogen may also be present at higher velocities (> 27,000 km/s). We use these observations to estimate explosion properties and derive a total ejecta mass of 2.7 Msolar, a kinetic energy of 1.0x10^{52} erg, and a 56Ni mass of 0.1-0.2 Msolar. Nebular spectra (t > 200d) exhibit an asymmetric double-peaked [OI] 6300,6364 emission profile that we associate with absorption in the supernova interior, although toroidal ejecta geometry is an al...

  17. The soft and hard X-rays thermal emission from star cluster winds with a supernova explosion

    CERN Document Server

    Castellanos-Ramirez, A; Esquivel, A; Toledo-Roy, J C; Olivares, J; Velazquez, P F

    2015-01-01

    Massive young star clusters contain dozens or hundreds of massive stars that inject mechanical energy in the form of winds and supernova explosions, producing an outflow which expands into their surrounding medium, shocking it and forming structures called superbubbles. The regions of shocked material can have temperatures in excess of 10$^6$ K, and emit mainly in thermal X-rays (soft and hard). This X-ray emission is strongly affected by the action of thermal conduction, as well as by the metallicity of the material injected by the massive stars. We present three-dimensional numerical simulations exploring these two effects, metallicity of the stellar winds and supernova explosions, as well as thermal conduction.

  18. SN 1957D in M83: A Young Supernova Remnant Emerges

    Science.gov (United States)

    Winkler, P. Frank; Long, K. S.; Blair, W. P.; Soria, R.; Godfrey, L. E. H.; Kuntz, K. D.; Plucinsky, P. P.; Whitmore, B. C.

    2012-05-01

    We report recent multi-wavelength observations of the remnant from SN 1957D, a core-collapse supernova in M83 and one of six SNe M83 has produced in the past century. SN 1957D was recovered as a radio SNR by Cowan & Branch (1983), and optically by Long et al. (1988). We have recently detected it for the first time in X-rays, in a long observation from Chandra. New HST WFC3 images resolve the SNR from the complex surrounding emission and reveal the local star field. The optical flux from SN 1957D is dominated by broad [O III] emission lines, the signature of fast-moving SN ejecta. The [O III] flux dropped precipitously between 1989 and 1991; a series of subsequent observations indicates continuing but more gradual decline. The width of the broad lines has remained roughly constant at about 3000 km/s (FWHM). At radio wavelengths, observations over the period 1990-2011 show a decline rate Sν t-3.9, far steeper than the rate observed between 1984 and 1990. Such evolution suggests early expansion into a circumstellar medium dominated by wind material from the progenitor, followed by a steeper decline as the blast wave overruns the edge of the wind material. The X-ray luminosity (0.3 - 10 keV) is 2.0 E37 erg/s, with a relatively hard spectrum. We cannot distinguish between a power law (indicating a probable pulsar and surrounding nebula) vs a hot thermal spectrum from the blast wave. However, the absorption is relatively high, NH 2 E22 cm-2, suggesting a dense local environment. Photometry of the local stellar population around SN 1957D, using HST WFC3 images, indicates a log(age) 7.3 and (remaining) stars up to about 11 M. This research is supported primarily by NASA through Chandra Grant G01-12115; PFW acknowledges additional support from NSF Grant AST-0908566.

  19. X-Rays from the Explosion Site: Fifteen Years of Light Curves of SN 1993J

    Science.gov (United States)

    Chandra, Poonam; Dwarkadas, Vikram V.; Ray, Alak; Immler, Stefan; Pooley, David

    2009-01-01

    We present a comprehensive analysis of the X-ray light curves of SN 1993J in a nearby galaxy M81. This is the only supernova other than SN 1987A, which is so extensively followed in the X-ray bands. Here we report on SN 1993J observations with the Chandra in the year 2005 and 2008, and Swift observations in 2005, 2006 and 2008. We combined these observations with all available archival data of SN 1993J, which includes ROSAT, ASCA, Chandra, and XMM-Newton, observations from 1993 April to 2006 August. In this paper we report the X-ray light curves of SN 1993J, extending up to fifteen years, in the soft (0.3-2.4 keV), hard (2-8 keV) and combined (0.3-8 keV) bands. The hard and soft-band fluxes decline at different rates initially, but after about 5 years they both undergo a t(sup -1) decline. The soft X-rays, which are initially low, start dominating after a few hundred days. We interpret that most of the emission below 8 keV is coming from the reverse shock which is radiative initially for around first 1000-2000 days and then turn into adiabatic shock. Our hydrodynamic simulation also confirms the reverse shock origin of the observed light curves. We also compare the Ha line luminosity of SN 1993J with its X-ray light curve and note that the Ha line luminosity has a fairly high fraction of the X-ray emission, indicating presence of clumps in the emitting plasma.

  20. Supernova 2013fc in a circumnuclear ring of a luminous infrared galaxy: the big brother of SN 1998S

    CERN Document Server

    Kangas, T; Kankare, E; Lundqvist, P; Väisänen, P; Childress, M; Pignata, G; McCully, C; Valenti, S; Vinko, J; Pastorello, A; Elias-Rosa, N; Fraser, M; Gal-Yam, A; Kotak, R; Kotilainen, J; Smartt, S J; Galbany, L; Harmanen, J; Howell, D A; Inserra, C; Marion, G H; Quimby, R M; Silverman, J M; Szalai, T; Wheeler, C J; Ashall, C; Benetti, S; Romero-Cañizales, C; Smith, K W; Sullivan, M; Takáts, K; Young, D R

    2015-01-01

    We present photometric and spectroscopic observations of SN 2013fc, a bright type II supernova (SN) in a circumnuclear star-forming ring in the luminous infrared galaxy ESO 154-G010, observed as part of the Public ESO Spectroscopic Survey of Transient Objects (PESSTO). SN 2013fc is both photometrically and spectroscopically similar to the well-studied type IIn SN 1998S and to the bright type II-L SN 1979C. It exhibits an initial linear decline after maximum, followed by a short plateau phase and a tail phase with a decline too fast for $^{56}$Co decay with full gamma-ray trapping. Initially the spectrum was blue and featureless. Later on, a strong broad ($\\sim 8000$ km s$^{-1}$) H$\\alpha$ emission profile became prominent. We apply a Starlight stellar population model fit to the SN location (observed when the SN had faded) to estimate both a high extinction of $A_V = 2.9 \\pm 0.2$ mag and an age of $10_{-2}^{+3}$ Myr for the underlying cluster. We compare the SN to SNe 1998S and 1979C and discuss its possible ...

  1. 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.

  2. Constraints on the explosion mechanism and progenitors of type Ia supernovae

    CERN Document Server

    Dessart, Luc; Hillier, D John; Khokhlov, Alexei

    2013-01-01

    Early time observations of SN2011fe show a variation in luminosity consistent with a simple fireball model of almost constant color (L ~ t^2). In contrast, our delayed detonations of Chandrasekhar-mass white dwarfs (DDC series) exhibit a steeper brightening rate (L ~ t^6) and redder colors early on. Treating additional unstable isotopes besides 56Ni has little impact. Strong chemical mixing reduces the discrepancy between model and observations a few days after explosion. In this paper, we explore other means to produce bluer and brighter SNe Ia at early times with pulsational-delayed detonations (PPDEL series). These models differ significantly from DDC models in that more carbon remains unburnt, newly created IMEs are confined to a narrower region in velocity space, and the shock-heated outer layers are of lower density and are much hotter immediately after the explosion. PDDEL models show bluer colors and a higher luminosity at early times. Our calculations show that at early times radioactive decay heatin...

  3. 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.

  4. A High-Resolution X-Ray and Optical Study of SN1006: Asymmetric Expansion and Small-Scale Structure in a Type Ia Supernova Remnant

    Science.gov (United States)

    Winkler, P. Frank; Williams, Brian J.; Reynolds, Stephen P.; Petre, Robert; Long, Knox S.; Katsuda, Satoru; Hwang, Una

    2014-01-01

    We introduce a deep (670 ks) X-ray survey of the entire SN 1006 remnant from the Chandra X-Ray Observatory, together with a deep Ha image of SN 1006 from the 4 m Blanco telescope at CTIO. Comparison with Chandra images from 2003 gives the first measurement of the X-ray proper motions around the entire periphery, carried out over a 9 yr baseline. We find that the expansion velocity varies significantly with azimuth. The highest velocity of approx.7400 km/s (almost 2.5 times that in the northwest (NW)) is found along the southeast (SE) periphery, where both the kinematics and the spectra indicate that most of the X-ray emission stems from ejecta that have been decelerated little, if at all. Asymmetries in the distribution of ejecta are seen on a variety of spatial scales. Si-rich ejecta are especially prominent in the SE quadrant, while O and Mg are more uniformly distributed, indicating large-scale asymmetries arising from the explosion itself. Neon emission is strongest in a sharp filament just behind the primary shock along the NWrim, where the pre-shock density is highest. Here the Ne is likely interstellar, while Ne within the shell may include a contribution from ejecta. Within the interior of the projected shell we find a few isolated "bullets" of what appear to be supernova ejecta that are immediately preceded by bowshocks seen in Ha, features that we interpret as ejecta knots that have reached relatively dense regions of the surrounding interstellar medium, but that appear in the interior in projection. Recent three-dimensional hydrodynamic models for Type Ia supernovae display small-scale features that strongly resemble the ones seen in X-rays in SN 1006; an origin in the explosion itself or from subsequent hydrodynamic instabilities both remain viable options. We have expanded the search for precursor X-ray emission ahead of a synchrotron-dominated shock front, as expected from diffusive shock acceleration theory, to numerous regions along both the

  5. Near-Infrared observations of the type Ib Supernova SN2006jc: evidence of interactions with dust

    CERN Document Server

    Di Carlo, E; Arkharov, A A; Massi, F; Larionov, V M; Efimova, N V; Dolci, M; Napoleone, N; Di Paola, A

    2007-01-01

    In the framework of a program for the monitoring of Supernovae in the Near-Infrared (NIR) carried out by the Teramo, Rome and Pulkovo observatories with the AZT-24 telescope, we observed the Supernova SN2006jc in the J,H,K photometric bands during a period of 7 months, starting ~36 days after its discovery. Our observations evidence a NIR re-brightening, peaking ~70 days after discovery, along with a reddening of H-K and J-H colors until 120 days from discovery. After that date, J-H seems to evolve towards bluer colors. Our data, complemented by IR, optical, UV and X-ray observations found in the literature, show that the re-brightening is produced by hot dust surrounding the supernova, formed in the interaction of the ejecta with dense circumstellar matter.

  6. The rotation of surviving companion stars after type Ia supernova explosions in the WD+MS scenario

    CERN Document Server

    Liu, Zheng-Wei; Roepke, Friedrich K; Edelmann, Philipp; Hillebrandt, Wolfgang; Kerzendorf, Wolfgang E; Wang, Bo; Han, Zhan-Wen

    2013-01-01

    In the SD scenario of SNe Ia the companion survives the SN explosion and thus should be visible near the center of the SN remnant and may show some unusual features. A promising approach to test progenitor models of SNe Ia is to search for the companion in SNRs. Here we present the results of 3D hydrodynamics simulations of the interaction between the SN Ia blast wave and a MS companion taking into consideration its orbital motion and spin. The primary goal of this work is to investigate the rotation of surviving companions after SN Ia explosions in the WD+MS scenario. We use Eggleton's code including the optically thick accretion wind model to obtain realistic models of companions. The impact of the SN blast wave on these companions is followed in 3D hydrodynamic simulations employing the SPH code GADGET3. We find that the rotation of the companion does not significantly affect the amount of stripped mass and the kick velocity caused by the SN impact. However, in our simulations, the rotational velocity of t...

  7. A luminous, blue progenitor system for the type Iax supernova 2012Z.

    Science.gov (United States)

    McCully, Curtis; Jha, Saurabh W; Foley, Ryan J; Bildsten, Lars; Fong, Wen-fai; Kirshner, Robert P; Marion, G H; Riess, Adam G; Stritzinger, Maximilian D

    2014-08-07

    Type Iax supernovae are stellar explosions that are spectroscopically similar to some type Ia supernovae at the time of maximum light emission, except with lower ejecta velocities. They are also distinguished by lower luminosities. At late times, their spectroscopic properties diverge from those of other supernovae, but their composition (dominated by iron-group and intermediate-mass elements) suggests a physical connection to normal type Ia supernovae. Supernovae of type Iax are not rare; they occur at a rate between 5 and 30 per cent of the normal type Ia rate. The leading models for type Iax supernovae are thermonuclear explosions of accreting carbon-oxygen white dwarfs that do not completely unbind the star, implying that they are 'less successful' versions of normal type Ia supernovae, where complete stellar disruption is observed. Here we report the detection of the luminous, blue progenitor system of the type Iax SN 2012Z in deep pre-explosion imaging. The progenitor system's luminosity, colours, environment and similarity to the progenitor of the Galactic helium nova V445 Puppis suggest that SN 2012Z was the explosion of a white dwarf accreting material from a helium-star companion. Observations over the next few years, after SN 2012Z has faded, will either confirm this hypothesis or perhaps show that this supernova was actually the explosive death of a massive star.

  8. SALT spectroscopic classification of PS16efm (= SN 2016fxu) as a type-Ic supernova after maximum light

    Science.gov (United States)

    Jha, S. W.; Dettman, K.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Kotze, M.

    2016-09-01

    We obtained SALT (+RSS) spectroscopy of PS16efm (= SN 2016fxu) on 2016 Sep 8.0 UT, covering the wavelength range 350-920 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows PS16efm is a type-Ic supernova approximately two to three weeks past maximum light.

  9. Neutron stars and supernova explosions in the framework of Landau's theory

    Science.gov (United States)

    Zheng, Hua; Sahagun, Jaime; Bonasera, Aldo

    2015-07-01

    In this paper, a general formula of the symmetry energy for many-body interaction is proposed and the commonly used two-body interaction symmetry energy is recovered. Within Landau's theory (Lt), we generalize two equations of state (EoS) CCSδ3 and CCSδ5 to asymmetric nuclear matter. We assume that the density and density difference between protons and neutrons divided by their sum are order parameters. We use different EoS to study neutron stars by solving the TOV equations. We demonstrate that different EoS give different mass and radius relation for neutron stars even when they have exactly the same ground state (gs) properties (E/A, ρ0, K, S, L and Ksym). Furthermore, for one EoS we change Ksym and fix all the other gs parameters. We find that for some Ksym the EoS becomes unstable at high density even for neutron matter. This suggests that a neutron star (NS) can exist below and above the instability region but in different states: a quark gluon plasma (QGP) at high density and baryonic matter at low density. If the star's central density is in the instability region, then we associate these conditions to the occurrence of supernovae (SN).

  10. A New Multi-Dimensional General Relativistic Neutrino Hydrodynamics Code for Core-Collapse Supernovae II. Relativistic Explosion Models of Core-Collapse Supernovae

    CERN Document Server

    Mueller, B; Marek, A

    2012-01-01

    We present the first two-dimensional general relativistic (GR) simulations of stellar core collapse and explosion with the CoCoNuT hydrodynamics code in combination with the VERTEX solver for energy-dependent, three-flavor neutrino transport, using the extended conformal flatness condition for approximating the spacetime metric and a ray-by-ray-plus ansatz to tackle the multi-dimensionality of the transport. For both of the investigated 11.2 and 15 solar mass progenitors we obtain successful, though seemingly marginal, neutrino-driven supernova explosions. This outcome and the time evolution of the models basically agree with results previously obtained with the PROMETHEUS hydro solver including an approximative treatment of relativistic effects by a modified Newtonian potential. However, GR models exhibit subtle differences in the neutrinospheric conditions compared to Newtonian and pseudo-Newtonian simulations. These differences lead to significantly higher luminosities and mean energies of the radiated ele...

  11. p-process nucleosynthesis via proton-capture reactions in thermonuclear supernovae explosions

    Directory of Open Access Journals (Sweden)

    Endres Anne

    2015-01-01

    Full Text Available Model calculations within the framework of the so-called γ process show an underproduction of the p nucleus with the highest isotopic abundace 92Mo. This discrepancy can be narrowed by taking into account the alternative production site of a type Ia supernova explosion. Here, the nucleus 92Mo can be produced by a sequence of proton-capture reactions. The amount of 92Mo nuclei produced via this reaction chain is most sensitive to the reactions 90Zr(p,γ and 91Nb(p,γ. Both rates have to be investigated experimentally to study the impact of this nucleosynthesis aspect on the long-standing 92Mo-problem. We have already measured the proton-capture reaction on 90Zr using high-resolution in-beam γ-ray spectroscopy. In this contribution, we will present our preliminary results of the total cross sections as well as the partial cross sections. Furthermore, we plan to measure the 91Nb(p,γ reaction soon. Due to the radioactive target material, the 91Nb nuclei have to be produced prior to the experiment. The current status of this production will be presented in this contribution.

  12. Type Ia Supernovae: Can Coriolis Force Break the Symmetry of the Gravitational Confined Detonation Explosion Mechanism?

    Science.gov (United States)

    García-Senz, D.; Cabezón, R. M.; Domínguez, I.; Thielemann, F. K.

    2016-03-01

    Currently the number of models aimed at explaining the phenomena of type Ia supernovae is high and distinguishing between them is a must. In this work we explore the influence of rotation on the evolution of the nuclear flame that drives the explosion in the so-called gravitational confined detonation models. Assuming that the flame starts in a pointlike region slightly above the center of the white dwarf (WD) and adding a moderate amount of angular velocity to the star we follow the evolution of the deflagration using a smoothed particle hydrodynamics code. We find that the results are very dependent on the angle between the rotational axis and the line connecting the initial bubble of burned material with the center of the WD at the moment of ignition. The impact of rotation is larger for angles close to 90° because the Coriolis force on a floating element of fluid is maximum and its principal effect is to break the symmetry of the deflagration. Such symmetry breaking weakens the convergence of the nuclear flame at the antipodes of the initial ignition volume, changing the environmental conditions around the convergence region with respect to non-rotating models. These changes seem to disfavor the emergence of a detonation in the compressed volume at the antipodes and may compromise the viability of the so-called gravitational confined detonation mechanism.

  13. TYPE Ia SUPERNOVAE: CAN CORIOLIS FORCE BREAK THE SYMMETRY OF THE GRAVITATIONAL CONFINED DETONATION EXPLOSION MECHANISM?

    Energy Technology Data Exchange (ETDEWEB)

    García-Senz, D. [Departament de Física, UPC, Comte d’Urgell 187, E-08036 Barcelona (Spain); Cabezón, R. M.; Thielemann, F. K. [Departement Physik, Universität Basel. Klingelbergstrasse, 82, 4056 Basel (Switzerland); Domínguez, I., E-mail: domingo.garcia@upc.edu, E-mail: ruben.cabezon@unibas.ch [Departamento de Física, Teórica y del Cosmos, Universidad de Granada, E-18071 Granada (Spain)

    2016-03-10

    Currently the number of models aimed at explaining the phenomena of type Ia supernovae is high and distinguishing between them is a must. In this work we explore the influence of rotation on the evolution of the nuclear flame that drives the explosion in the so-called gravitational confined detonation models. Assuming that the flame starts in a pointlike region slightly above the center of the white dwarf (WD) and adding a moderate amount of angular velocity to the star we follow the evolution of the deflagration using a smoothed particle hydrodynamics code. We find that the results are very dependent on the angle between the rotational axis and the line connecting the initial bubble of burned material with the center of the WD at the moment of ignition. The impact of rotation is larger for angles close to 90° because the Coriolis force on a floating element of fluid is maximum and its principal effect is to break the symmetry of the deflagration. Such symmetry breaking weakens the convergence of the nuclear flame at the antipodes of the initial ignition volume, changing the environmental conditions around the convergence region with respect to non-rotating models. These changes seem to disfavor the emergence of a detonation in the compressed volume at the antipodes and may compromise the viability of the so-called gravitational confined detonation mechanism.

  14. Type Ia Supernovae: Can Coriolis force break the symmetry of the gravitational confined detonation explosion mechanism?

    CERN Document Server

    García-Senz, D; Domínguez, I; Thielemann, F K

    2015-01-01

    Nowadays the number of models aimed at explaining the Type Ia supernova phenomenon is high and discriminating between them is a must-do. In this work we explore the influence of rotation in the evolution of the nuclear flame which drives the explosion in the so called gravitational confined detonation models. Assuming that the flame starts in a point-like region slightly above the center of the white dwarf (WD) and adding a moderate amount of angular velocity to the star we follow the evolution of the deflagration using a smoothed particle hydrodynamics code. We find that the results are very dependent on the angle between the rotational axis and the line connecting the initial bubble of burned material with the center of the white dwarf at the moment of the ignition. The impact of rotation is larger for angles close to 90{\\deg} because the Coriolis force on a floating element of fluid is maximum, and its principal effect is to break the symmetry of the deflagration. Such symmetry breaking weakens the converg...

  15. Progenitor-Explosion Connection and Remnant Birth Masses for Neutrino-Driven Supernovae of Iron-Core Progenitors

    CERN Document Server

    Ugliano, Marcella; Marek, Andreas; Arcones, Almudena

    2012-01-01

    We perform hydrodynamic supernova simulations in spherical symmetry for over 100 single stars of solar metallicity to explore the progenitor-explosion and progenitor-remnant connections established by the neutrino-driven mechanism. We use an approximative treatment of neutrino transport and replace the high-density interior of the neutron star (NS) by an inner boundary condition based on an analytic proto-NS core-cooling model, whose free parameters are chosen such that explosion energy, nickel production, and energy release by the compact remnant of progenitors around 20 solar masses are compatible with Supernova 1987A. Thus we are able to simulate the accretion phase, initiation of the explosion, subsequent neutrino-driven wind phase for 15-20 s, and the further evolution of the blast wave for hours to days until fallback is completed. Our results challenge long-standing paradigms. We find that remnant mass, launch time, and properties of the explosion depend strongly on the stellar structure and exhibit la...

  16. Progenitor-dependent Explosion Dynamics in Self-consistent, Axisymmetric Simulations of Neutrino-driven Core-collapse Supernovae

    CERN Document Server

    Summa, Alexander; Janka, Hans-Thomas; Melson, Tobias; Marek, Andreas; Müller, Bernhard

    2015-01-01

    We present self-consistent, axisymmetric core-collapse supernova simulations performed with the Prometheus-Vertex code for 18 pre-supernova models in the range of 11-28 solar masses, including progenitors recently investigated by other groups. All models develop explosions, but depending on the progenitor structure, they can be divided into two classes. With a steep density decline at the Si/Si-O interface, the arrival of this interface at the shock front leads to a sudden drop of the mass-accretion rate, triggering a rapid approach to explosion. With a more gradually decreasing accretion rate, it takes longer for the neutrino heating to overcome the accretion ram pressure and explosions set in later. Early explosions are facilitated by high mass-accretion rates after bounce and correspondingly high neutrino luminosities combined with a pronounced drop of the accretion rate and ram pressure at the Si/Si-O interface. Because of rapidly shrinking neutron star radii and receding shock fronts after the passage th...

  17. SN1987A-Neutrino emission from Supernova': in Dynamic universe model of cosmology

    Science.gov (United States)

    Naga Parameswara Gupta, Satyavarapu

    SN1987A-Neutrino emission from supernova before the star bursts' is an important discovery, when viewed from `Dynamic universe model of cosmology' point of view. In OMEG05, we have successfully presented the reasons for calculation error called `missing mass' in an inhomoge-neous, anisotropic and multi-body Dynamic universe Model, where this error is not occurring. But there are some new voices that say about generation of some flavors of neutrinos during Bigbang. We find from SN1987A Neutrino generation covers all flavors. Remaining flavors of Neutrinos are generated from sun and stars. This covers the whole spectrum. This paper covers all these aspects. And other earlier results by Dynamic Universe Model 1. Offers Singularity free solutions 2. Non-collapsing Galaxy structures 3. Solving Missing mass in Galaxies, and it finds reason for Galaxy circular velocity curves. . . . 4. Blue shifted and red shifted Galaxies co-existence. . . 5. Explains the force behind expansion of universe. 6. Explains the large voids and non-uniform matter densities. 7. Explains the Pioneer anomaly 8. Predicts the trajectory of New Horizons satellite. 9 Jeans swindle test 10. Existence of large number of blue shifted Galaxies `SITA Simulations' software was developed about 18 years back for Dynamic Universe Model of Cosmology. It is based on Newtonian physics. It is Classical singularity free N-body tensor solution to the old problem announced by King Oscar II and tried by Poincare in year AD1888 for 133 masses, tested extensively for so many years. This was developed on 486 based PC of those days; the same software was used repeatedly for so many years for solving different Physical problems on Different PCs and Laptops. It is based on Dynamic Universe Model's mathematical back ground.

  18. An Upper Mass Limit on a Red Supergiant Progenitor for the Type II-Plateau Supernova SN 2006my

    Science.gov (United States)

    Leonard, Douglas C.; Gal-Yam, Avishay; Fox, Derek B.; Cameron, P. B.; Johansson, Erik M.; Kraus, Adam L.; Le Mignant, David; van Dam, Marcos A.

    2008-12-01

    We analyze two pre-supernova (SN) and three post-SN high-resolution images of the site of the Type II-Plateau supernova SN 2006my in an effort to either detect the progenitor star or to constrain its properties. Following image registration, we find that an isolated stellar object is not detected at the location of SN 2006my in either of the two pre-SN images. In the first, an I-band image obtained with the Wide-Field and Planetary Camera 2 on board the Hubble Space Telescope, the offset between the SN 2006my location and a detected source (“Source 1”) is too large: ≥0.08‧‧, which corresponds to a confidence level of non-association of 96% from our most liberal estimates of the transformation and measurement uncertainties. In the second, a similarly obtained V-band image, a source is detected (“Source 2”) that has overlap with the SN 2006my location but is definitively an extended object. Through artificial star tests carried out on the precise location of SN 2006my in the images, we derive a 3 σ upper bound on the luminosity of a red supergiant that could have remained undetected in our pre-SN images of log L/L⊙ = 5.10, which translates to an upper bound on such a star’s initial mass of 15 M⊙ from the STARS stellar evolutionary models. Although considered unlikely, we can not rule out the possibility that part of the light comprising Source 1, which exhibits a slight extension relative to other point sources in the image, or part of the light contributing to the extended Source 2, may be due to the progenitor of SN 2006my. Only additional, high-resolution observations of the site taken after SN 2006my has faded beyond detection can confirm or reject these possibilities. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was

  19. OGLE-2013-SN-079: a lonely supernova consistent with a helium shell detonation

    CERN Document Server

    Inserra, C; Wyrzykowski, L; Smartt, S J; Fraser, M; Nicholl, M; Shen, K J; Jerkstrand, A; Gal-Yam, A; Howell, D A; Maguire, K; Mazzali, P; Valenti, S; Taubenberger, S; Benitez-Herrera, S; Bersier, D; Blagorodnova, N; Campbell, H; Chen, T -W; Elias-Rosa, N; Hillebrandt, W; Kostrzewa-Rutkowska, Z; Kozlowski, S; Kromer, M; Lyman, J D; Polshaw, J; Ropke, F K; Ruiter, A J; Smith, K; Spiro, S; Sullivan, M; Yaron, O; Young, D; Yuan, F

    2014-01-01

    We present observational data for a peculiar supernova discovered by the OGLE-IV survey and followed by the Public ESO Spectroscopic Survey for Transient Objects. The inferred redshift of z=0.07 implies an absolute magnitude in the rest-frame I-band of M$_{I}\\sim-17.6$ mag. This places it in the luminosity range between normal Type Ia SNe and novae. Optical and near infrared spectroscopy reveal mostly Ti and Ca lines, and an unusually red color arising from strong depression of flux at rest wavelengths <5000 \\AA. To date, this is the only reported SN showing Ti-dominated spectra. Our multi band and bolometric lightcurves, as well as the spectral evolution, are in reasonable agreement with the predictions of models for the pure detonation of a helium shell around a low-mass CO white dwarf and "double-detonation" models that include a secondary detonation of a CO core following a primary detonation in an overlying helium shell.

  20. Highly Luminous Supernovae associated with Gamma-Ray Bursts I.: GRB 111209A/SN 2011kl in the Context of Stripped-Envelope and Superluminous Supernovae

    CERN Document Server

    Kann, D A; E., F Olivares; Klose, S; Rossi, A; Perley, D A; Krühler, T; Greiner, J; Guelbenzu, A Nicuesa; Elliott, J; Knust, F; Filgas, R; Pian, E; Mazzali, P; Fynbo, J P U; Leloudas, G; Afonso, P M J; Delvaux, C; Graham, J F; Rau, A; Schmidl, S; Schulze, S; Tanga, M; Updike, A C; Varela, K

    2016-01-01

    We address the question whether GRB 111209A was a special event beyond its extreme duration alone, and whether it is a classical GRB or another kind of high-energy transient. Furthermore, we place SN 2011kl into the context of large samples of SNe, addressing in more detail the question of whether it could be radioactively powered. We present afterglow photometry obtained in seven bands with the GROND imager as well as in further seven bands with the UVOT telescope on-board \\emph{Swift}. The light curve is analysed by multi-band modelling and joint fitting with power-laws and broken power-laws. We model SN 2011kl using SN 1998bw as a template and derive a bolometric light curve including near-infrared data. We compare the optical afterglow and the properties of SN 2011kl to large ensembles we have analysed in earlier works, additional GRB-SNe analysed here, as well as literature results on stripped-envelope and superluminous supernovae. We find a strong, chromatic rebrightening event at $\\approx0.8$ days afte...

  1. SN 2010mb: Direct evidence for a supernova interacting with a large amount of hydrogen-free circumstellar material

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Ami, Sagi; Gal-Yam, Avishay; Rabinak, Itay; Yaron, Ofer; Arcavi, Iair; Ofek, Eran O. [Department of Particle Physics and Astrophysics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Mazzali, Paolo A. [Astrophysics Research Institute, Liverpool John Moores University. Liverpool L3 5RF (United Kingdom); Gnat, Orly [Racah Institute of Physics, The Hebrew University, 91904 Jerusalem (Israel); Modjaz, Maryam [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, room 529, New York, NY 10003 (United States); Sullivan, Mark [Department of Physics (Astrophysics), University of Oxford, DWB, Keble Road, Oxford, OX1 3RH (United Kingdom); Bildsten, Lars [Kavli Institute for Theoretical Physics and Department of Physics Kohn Hall, University of California, Santa Barbara, CA 93106 (United States); Poznanski, Dovi [School of Physics and Astronomy, Tel-Aviv University, Tel Aviv 69978 Israel (Israel); Bloom, Joshua S.; Nugent, Peter E. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Horesh, Assaf; Kulkarni, Shrinivas R.; Perley, Daniel [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Kasliwal, Mansi M. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Quimby, Robert [Kavli IPMU, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8583 (Japan); Xu, Dong, E-mail: sagi.ben-ami@weizmann.ac.il [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark)

    2014-04-10

    We present our observations of SN 2010mb, a Type Ic supernova (SN) lacking spectroscopic signatures of H and He. SN 2010mb has a slowly declining light curve (LC) (∼600 days) that cannot be powered by {sup 56}Ni/{sup 56}Co radioactivity, the common energy source for Type Ic SNe. We detect signatures of interaction with hydrogen-free circumstellar material including a blue quasi-continuum and, uniquely, narrow oxygen emission lines that require high densities (∼10{sup 9} cm{sup –3}). From the observed spectra and LC, we estimate that the amount of material involved in the interaction was ∼3 M {sub ☉}. Our observations are in agreement with models of pulsational pair-instability SNe described in the literature.

  2. 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.

  3. Nearby Supernova Factory Observations of SN 2007if: First Total Mass Measurement of a Super-Chandrasekhar-Mass Progenitor

    CERN Document Server

    Scalzo, R A; Antilogus, P; Aragon, C; Bailey, S; Bongard, C; Buton, C; Childress, M; Chotard, N; Copin, Y; Fakhouri, H K; Gal-Yam, A; Gangler, E; Hoyer, S; Kasliwal, M; Loken, S; Nugent, P E; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rau, A; Rigaudier, G; Runge, K; Smadja, G; Tao, C; Thomas, R C; Weaver, B; Wu, C

    2010-01-01

    We present photometric and spectroscopic observations of SN 2007if, an overluminous (M_V = -20.4), red (B-V = 0.16 at B-band maximum), slow-rising (t_rise = 24 days) type Ia supernova in a very faint (M_g = -14.10) host galaxy. A spectrum at 5 days past B-band maximum light is a direct match to the super-Chandrasekhar-mass candidate SN Ia 2003fg, showing Si II and C II at ~9000 km/s. A high signal-to-noise co-addition of the SN spectral time series reveals no Na I D absorption, suggesting negligible reddening in the host galaxy, and the late-time color evolution has the same slope as the Lira relation for normal SNe Ia. The ejecta appear to be well mixed, with no strong maximum in I-band and a diversity of iron-peak lines appearing in near-maximum-light spectra. SN2007 if also displays a plateau in the Si II velocity extending as late as +10 days, which we interpret as evidence for an overdense shell in the SN ejecta. We calculate the bolometric light curve of the SN and use it and the \\ion{Si}{2} velocity ev...

  4. Search for isotopic signatures of a supernova explosion close to the solar system in marine sediments; Recherche de signatures isotopiques dans les sediments marins de l'explosion d'une supernova proche du systeme solaire

    Energy Technology Data Exchange (ETDEWEB)

    Fitoussi, Caroline [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, (CSNSM) IN2P3/CNRS, Campus d' Orsay, Bat 108, 91405 Orsay (France)

    2006-06-15

    The recent observation of a {sup 60}Fe peak in a deep-sea ferro-manganese crust has been interpreted as due to a supernova explosion relatively close to the solar system 2.8 {+-} 0.4 Myr ago. To confirm this interpretation with better time-resolved measurements, and the simultaneous access, on the same sample, to other isotopes and geochemical phases, marine sediments seem to be a tool of choice. The objective of this work was to search for isotopic anomalies which would be characteristic for residues of this supernova. More specifically, {sup 129}I, {sup 60}Fe, and {sup 26}Al have been investigated, being measured by Accelerator Mass Spectrometry (AMS). Quantifying these nuclides' fluxes would help constrain stellar nucleosynthesis models. These residues are isotopes initially produced during hydrostatic and/or explosive nucleosynthesis. The physical conditions during the explosion (temperature, neutron density) are such that supernovae are thought to be good candidates for the astrophysical site of the r-process. The {sup 129}I study showed that measurement of pre-anthropogenic {sup 129}I/{sup 127}I ratios need a very strict control of the various potential {sup 129}I sources, especially when working with small quantities (micrograms) of iodine. This study revealed that the expected pre-anthropogenic {sup 129}I/{sup 127}I ratio for pre-nuclear samples in the marine environment shows a large discrepancy between theoretical calculations and experimental measurements. {sup 60}Fe and {sup 26}Al measurements allow us to conclude that, in the authigenic phase of the marine sediments, there is no {sup 60}Fe anomaly in the time interval defined by the signal found on the Fe-Mn crust (from 2.4 to 3.2 Myr), and no {sup 26}Al anomaly from 2.6 to 3.2 Myr. (author)

  5. Progenitor-dependent Explosion Dynamics in Self-consistent, Axisymmetric Simulations of Neutrino-driven Core-collapse Supernovae

    Science.gov (United States)

    Summa, Alexander; Hanke, Florian; Janka, Hans-Thomas; Melson, Tobias; Marek, Andreas; Müller, Bernhard

    2016-07-01

    We present self-consistent, axisymmetric core-collapse supernova simulations performed with the Prometheus-Vertex code for 18 pre-supernova models in the range of 11-28 M ⊙, including progenitors recently investigated by other groups. All models develop explosions, but depending on the progenitor structure, they can be divided into two classes. With a steep density decline at the Si/Si-O interface, the arrival of this interface at the shock front leads to a sudden drop of the mass-accretion rate, triggering a rapid approach to explosion. With a more gradually decreasing accretion rate, it takes longer for the neutrino heating to overcome the accretion ram pressure and explosions set in later. Early explosions are facilitated by high mass-accretion rates after bounce and correspondingly high neutrino luminosities combined with a pronounced drop of the accretion rate and ram pressure at the Si/Si-O interface. Because of rapidly shrinking neutron star radii and receding shock fronts after the passage through their maxima, our models exhibit short advection timescales, which favor the efficient growth of the standing accretion-shock instability. The latter plays a supportive role at least for the initiation of the re-expansion of the stalled shock before runaway. Taking into account the effects of turbulent pressure in the gain layer, we derive a generalized condition for the critical neutrino luminosity that captures the explosion behavior of all models very well. We validate the robustness of our findings by testing the influence of stochasticity, numerical resolution, and approximations in some aspects of the microphysics.

  6. The Extinction properties of and distance to the highly reddened Type~Ia supernova SN 2012cu

    Science.gov (United States)

    Huang, Xiaosheng; Raha, Zachary; Aldering, Greg Scott; Antilogus, Pierre; Bailey, Stephen J.; Charles, Baltay; Barbary, Kyle H.; Baugh, Derek; Boone, Kyle; Bongard, Sebastien; Buton, Clement; Chen, Juncheng; Chotard, Nicolas; Copin, Yannick; Fagrelius, Parker; Fakhouri, Hannah; Feindt, Ulrich; Fouchez, Dominique; Gangler, Emmanuel; Hayden, Brian; Hillebrandt, Wolfgang; Kim, Alex G.; Kowalski, Marek; Leget, Pierre-Francois; Lombardo, Simona; Nordin, Jakob; Pain, Reynald; Pecontal, Emmanuel; Pereira, Rui; Perlmutter, Saul; Rabinowitz, David L.; Rigault, Mickael; Rubin, David; Runge, Karl; Saunders, Clare; Smadja, Gerard; Sofiatti, Caroline; Stocker, Andrew; Suzuki, Nao; Taubenberger, Stefan; Tao, Charling; Thomas, Rollin

    2017-01-01

    Correction of Type Ia SN brightnesses for extinction by dust has proven to be a vexing problem. Here we study the dust foreground to the highly reddened SN 2012cu, which is projected onto a dust lane in the galaxy NGC 4772. The analysis is based on multi-epoch, spectrophotometric observations spanning 3,300 - 9,200 A, obtained by the Nearby Supernova Factory. Phase-matched comparison of the spectroscopically twinned SN 2012cu and SN 2011fe across 10 epochs results in the best-fit color excess of (E(B - V ), RMS) = (1.00, 0.03) and total-to-selective extinction ratio of (RV , RMS) = (2.95, 0.09) toward SN 2012cu within its host galaxy. We further identify several diffuse interstellar bands, and compare the 5780 A band with the dust-to-band ratio for the Milky Way. Overall, we find the foreground dust-extinction properties for SN 2012cu to be consistent with those of the Milky Way. Furthermore we find no evidence for significant time variation in any of these extinction tracers. We also compare the dust extinction curves of Cardelli et al. (1989), O’Donnell (1994), and Fitzpatrick (1999), and find the predictions of Fitzpatrick (1999) fit SN 2012cu the best. Finally, the distance to NGC4772, the host of SN 2012cu, at a redshift of z = 0.0035, often assigned to the Virgo Southern Extension, is determined to be 16.6±1.1 Mpc. We compare this result with distance measurements in the literature.

  7. 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.

  8. 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.

  9. EmpiriciSN: Re-sampling Observed Supernova/Host Galaxy Populations Using an XD Gaussian Mixture Model

    Energy Technology Data Exchange (ETDEWEB)

    Holoien, Thomas W.-S.; /Ohio State U., Dept. Astron. /Ohio State U., CCAPP /KIPAC, Menlo Park /SLAC; Marshall, Philip J.; Wechsler, Risa H.; /KIPAC, Menlo Park /SLAC

    2017-05-11

    We describe two new open-source tools written in Python for performing extreme deconvolution Gaussian mixture modeling (XDGMM) and using a conditioned model to re-sample observed supernova and host galaxy populations. XDGMM is new program that uses Gaussian mixtures to perform density estimation of noisy data using extreme deconvolution (XD) algorithms. Additionally, it has functionality not available in other XD tools. It allows the user to select between the AstroML and Bovy et al. fitting methods and is compatible with scikit-learn machine learning algorithms. Most crucially, it allows the user to condition a model based on the known values of a subset of parameters. This gives the user the ability to produce a tool that can predict unknown parameters based on a model that is conditioned on known values of other parameters. EmpiriciSN is an exemplary application of this functionality, which can be used to fit an XDGMM model to observed supernova/host data sets and predict likely supernova parameters using a model conditioned on observed host properties. It is primarily intended to simulate realistic supernovae for LSST data simulations based on empirical galaxy properties.

  10. EmpiriciSN: Re-sampling Observed Supernova/Host Galaxy Populations Using an XD Gaussian Mixture Model

    Science.gov (United States)

    Holoien, Thomas W.-S.; Marshall, Philip J.; Wechsler, Risa H.

    2017-06-01

    We describe two new open-source tools written in Python for performing extreme deconvolution Gaussian mixture modeling (XDGMM) and using a conditioned model to re-sample observed supernova and host galaxy populations. XDGMM is new program that uses Gaussian mixtures to perform density estimation of noisy data using extreme deconvolution (XD) algorithms. Additionally, it has functionality not available in other XD tools. It allows the user to select between the AstroML and Bovy et al. fitting methods and is compatible with scikit-learn machine learning algorithms. Most crucially, it allows the user to condition a model based on the known values of a subset of parameters. This gives the user the ability to produce a tool that can predict unknown parameters based on a model that is conditioned on known values of other parameters. EmpiriciSN is an exemplary application of this functionality, which can be used to fit an XDGMM model to observed supernova/host data sets and predict likely supernova parameters using a model conditioned on observed host properties. It is primarily intended to simulate realistic supernovae for LSST data simulations based on empirical galaxy properties.

  11. SN Refsdal

    DEFF Research Database (Denmark)

    Kelly, P. L.; Brammer, G.; Selsing, J.;

    2016-01-01

    We have acquired Hubble Space Telescope (HST) and Very Large Telescope near-infrared spectra and images of supernova (SN) Refsdal after its discovery as an Einstein cross in Fall 2014. The HST light curve of SN Refsdal matches the distinctive, slowly rising light curves of SN 1987A-like supernovae...

  12. It's Alive! The Supernova Impostor 1961V

    CERN Document Server

    Van Dyk, Schuyler D

    2011-01-01

    Reports of the death of the precursor of Supernova (SN) 1961V in NGC 1058 are exaggerated. Consideration of the best astrometric data shows that the star, known as "Object 7," lies at the greatest proximity to SN 1961V and is the likely survivor of the "SN impostor" super-outburst. SN 1961V does not coincide with a neighboring radio source and is therefore not a radio SN. Additionally, the current properties of Object 7, based on data obtained with the Hubble Space Telescope, are consistent with it being a quiescent Luminous Blue Variable (LBV). Furthermore, post-explosion non-detections by the Spitzer Space Telescope do not necessarily and sufficiently rule out a surviving LBV. We therefore consider, based on the available evidence, that it is yet a bit premature to reclassify SN 1961V as a bona fide SN. The inevitable demise of this star, though, may not be too far off.

  13. Failure of a neutrino-driven explosion after core-collapse may lead to a thermonuclear supernova

    CERN Document Server

    Kushnir, Doron

    2014-01-01

    We demonstrate that $\\sim10$ seconds after core-collapse of a massive star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial density and composition profiles, assuming the neutrinos failed to explode the star. The explosion may lead to a successful supernova, as first suggested by Burbidge, Burbidge, Fowler and Hoyle (1957). We perform a series of one-dimensional (1D) calculations of collapsing massive stars with simplified initial density profiles (similar to the results of stellar evolution calculations) and various compositions (not similar to 1D stellar evolution calculations). We assume that the neutrinos escaped with negligible effect on the outer layers, which inevitably collapse. As the shells collapse, they compress and heat up adiabatically, enhancing the rate of thermonuclear burning. In some cases, where significant shells of mixed helium and oxygen are present with pre-collapsed burning times of $\\lesssim100\\,\\textrm{s}$ ($\\approx10$ times the free-fall time), a ...

  14. Radio and X-Ray Observations of SN 2006jd: Another Strongly Interacting Type IIn Supernova

    Science.gov (United States)

    Chandra, Poonam; Chevalier, Roger A.; Chugai, Nikolai; Fransson, Claes; Irwin, Christopher M.; Soderberg, Alicia M.; Chakraborti, Sayan; Immler, Stefan

    2012-01-01

    We report four years of radio and X-ray monitoring of the Type IIn supernova SN 2006jd at radio wavelengths with the Very Large Array, Giant Metrewave Radio Telescope and Expanded Very Large Array at X-ray wavelengths with Chandra, XMM-Newton and Swift-XRT. We assume that the radio and X-ray emitting particles are produced by shock interaction with a dense circumstellar medium. The radio emission shows an initial rise that can be attributed to free-free absorption by cool gas mixed into the nonthermal emitting region external free-free absorption is disfavored because of the shape of the rising light curves and the low gas column density inferred along the line of sight to the emission region. The X-ray luminosity implies a preshock circumstellar density approximately 10(exp 6) per cubic meter at a radius r approximately 2 x 10(exp 16) centimeter, but the column density inferred from the photoabsorption of X-rays along the line of sight suggests a significantly lower density. The implication may be an asymmetry in the interaction. The X-ray spectrum shows Fe line emission at 6.9 keV that is stronger than is expected for the conditions in the X-ray emitting gas. We suggest that cool gas mixed into the hot gas plays a role in the line emission. Our radio and X-ray data both suggest the density profile is flatter than r2 because of the slow evolution of the unabsorbed emission.

  15. Discovery of a Supernova Explosion at Half the Age of the Universe and its Cosmological Implications

    CERN Document Server

    Perlmutter, S; Valle, M D; Deustua, S; Ellis, Richard S; Fabbro, S; Fruchter, A S; Goldhaber, Gerson; Goobar, A; Groom, D E; Hook, I M; Kim, A G; Kim, M Y; Knop, R A; Lidman, C E; McMahon, R G; Nugent, P; Pain, R; Panagia, N; Pennypacker, C R; Ruiz-Lapuente, P; Schaefer, B; Walton, N A; Nugent, Peter

    1998-01-01

    The ultimate fate of the universe, infinite expansion or a big crunch, can be determined by measuring the redshifts, apparent brightnesses, and intrinsic luminosities of very distant supernovae. Recent developments have provided tools that make such a program practicable: (1) Studies of relatively nearby Type Ia supernovae (SNe Ia) have shown that their intrinsic luminosities can be accurately determined; (2) New research techniques have made it possible to schedule the discovery and follow-up observations of distant supernovae, producing well over 50 very distant (z = 0.3 -- 0.7) SNe Ia to date. These distant supernovae provide a record of changes in the expansion rate over the past several billion years. By making precise measurements of supernovae at still greater distances, and thus extending this expansion history back far enough in time, we can distinguish the slowing caused by the gravitational attraction of the universe's mass density Omega_M from the effect of a possibly inflationary pressure caused ...

  16. A NEW MULTI-DIMENSIONAL GENERAL RELATIVISTIC NEUTRINO HYDRODYNAMICS CODE FOR CORE-COLLAPSE SUPERNOVAE. II. RELATIVISTIC EXPLOSION MODELS OF CORE-COLLAPSE SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Bernhard; Janka, Hans-Thomas; Marek, Andreas, E-mail: bjmuellr@mpa-garching.mpg.de, E-mail: thj@mpa-garching.mpg.de [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

    2012-09-01

    We present the first two-dimensional general relativistic (GR) simulations of stellar core collapse and explosion with the COCONUT hydrodynamics code in combination with the VERTEX solver for energy-dependent, three-flavor neutrino transport, using the extended conformal flatness condition for approximating the space-time metric and a ray-by-ray-plus ansatz to tackle the multi-dimensionality of the transport. For both of the investigated 11.2 and 15 M{sub Sun} progenitors we obtain successful, though seemingly marginal, neutrino-driven supernova explosions. This outcome and the time evolution of the models basically agree with results previously obtained with the PROMETHEUS hydro solver including an approximative treatment of relativistic effects by a modified Newtonian potential. However, GR models exhibit subtle differences in the neutrinospheric conditions compared with Newtonian and pseudo-Newtonian simulations. These differences lead to significantly higher luminosities and mean energies of the radiated electron neutrinos and antineutrinos and therefore to larger energy-deposition rates and heating efficiencies in the gain layer with favorable consequences for strong nonradial mass motions and ultimately for an explosion. Moreover, energy transfer to the stellar medium around the neutrinospheres through nucleon recoil in scattering reactions of heavy-lepton neutrinos also enhances the mentioned effects. Together with previous pseudo-Newtonian models, the presented relativistic calculations suggest that the treatment of gravity and energy-exchanging neutrino interactions can make differences of even 50%-100% in some quantities and is likely to contribute to a finally successful explosion mechanism on no minor level than hydrodynamical differences between different dimensions.

  17. The Superluminous Supernova SN 2017egm in the Nearby Galaxy NGC 3191: A Metal-rich Environment Can Support a Typical SLSN Evolution

    Science.gov (United States)

    Nicholl, Matt; Berger, Edo; Margutti, Raffaella; Blanchard, Peter K.; Guillochon, James; Leja, Joel; Chornock, Ryan

    2017-08-01

    At redshift z = 0.03, the recently discovered SN 2017egm is the nearest Type I superluminous supernova (SLSN) to date and first near the center of a massive spiral galaxy (NGC 3191). Using SDSS spectra of NGC 3191, we find a metallicity ˜2 {Z}⊙ at the nucleus and ˜1.3 {Z}⊙ for a star-forming region at a radial offset similar to SN 2017egm. Archival radio-to-UV photometry reveals a star formation rate of ˜15 {M}⊙ yr-1 (with ˜70% dust obscured), which can account for a Swift X-ray detection and a stellar mass of ˜ {10}10.7 {M}⊙ . We model the early UV-optical light curves with a magnetar central-engine model, using the Bayesian light curve fitting tool MOSFiT. The fits indicate an ejecta mass of 2-4 {M}⊙ , a spin period of 4-6 ms, a magnetic field of (0.7{--}1.7)× {10}14 G, and a kinetic energy of 1{--}2× {10}51 erg. These parameters are consistent with the overall distributions for SLSNe, modeled by Nicholl et al., although the derived mass and spin are toward the low end, possibly indicating an enhanced loss of mass and angular momentum before explosion. This has two implications: (i) SLSNe can occur at solar metallicity, although with a low fraction of ˜10%, and (ii) metallicity has at most a modest effect on their properties. Both conclusions are in line with results for long gamma-ray bursts. Assuming a monotonic rise gives an explosion date of MJD 57889 ± 1. However, a short-lived excess in the data relative to the best-fitting models may indicate an early-time “bump.” If confirmed, SN 2017egm would be the first SLSN with a spectrum during the bump phase; this shows the same O ii lines seen at maximum light, which may be an important clue for explaining these bumps.

  18. Supernova progenitors, their variability and the Type IIP Supernova ASASSN-16fq in M66

    Science.gov (United States)

    Kochanek, C. S.; Fraser, M.; Adams, S. M.; Sukhbold, T.; Prieto, J. L.; Müller, T.; Bock, G.; Brown, J. S.; Dong, Subo; Holoien, T. W.-S.; Khan, R.; Shappee, B. J.; Stanek, K. Z.

    2017-05-01

    We identify a pre-explosion counterpart to the nearby Type IIP supernova ASASSN-16fq (SN 2016cok) in archival Hubble Space Telescope data. The source appears to be a blend of several stars that prevents obtaining accurate photometry. However, with reasonable assumptions about the stellar temperature and extinction, the progenitor almost certainly had an initial mass M* ≲ 17 M⊙, and was most likely in the mass range of M* = 8-12 M⊙. Observations once ASASSN-16fq has faded will have no difficulty accurately determining the properties of the progenitor. In 8 yr of Large Binocular Telescope (LBT) data, no significant progenitor variability is detected to rms limits of roughly 0.03 mag. Of the six nearby supernova (SN) with constraints on the low-level variability, SN 1987A, SN 1993J, SN 2008cn, SN 2011dh, SN 2013ej and ASASSN-16fq, only the slowly fading progenitor of SN 2011dh showed clear evidence of variability. Excluding SN 1987A, the 90 per cent confidence limit implied by these sources on the number of outbursts over the last decade before the SN that last longer than 0.1 yr (full width at half-maximum) and are brighter than MR < -8 mag is approximately Nout ≲ 3. Our continuing LBT monitoring programme will steadily improve constraints on pre-SN progenitor variability at amplitudes far lower than achievable by SN surveys.

  19. NERO- a post-maximum supernova radiation transport code

    Science.gov (United States)

    Maurer, I.; Jerkstrand, A.; Mazzali, P. A.; Taubenberger, S.; Hachinger, S.; Kromer, M.; Sim, S.; Hillebrandt, W.

    2011-12-01

    The interpretation of supernova (SN) spectra is essential for deriving SN ejecta properties such as density and composition, which in turn can tell us about their progenitors and the explosion mechanism. A very large number of atomic processes are important for spectrum formation. Several tools for calculating SN spectra exist, but they mainly focus on the very early or late epochs. The intermediate phase, which requires a non-local thermodynamic equilibrium (NLTE) treatment of radiation transport has rarely been studied. In this paper, we present a new SN radiation transport code, NERO, which can look at those epochs. All the atomic processes are treated in full NLTE, under a steady-state assumption. This is a valid approach between roughly 50 and 500 days after the explosion depending on SN type. This covers the post-maximum photospheric and the early and the intermediate nebular phase. As a test, we compare NERO to the radiation transport code of Jerkstrand, Fransson & Kozma and to the nebular code of Mazzali et al. All three codes have been developed independently and a comparison provides a valuable opportunity to investigate their reliability. Currently, NERO is one-dimensional and can be used for predicting spectra of synthetic explosion models or for deriving SN properties by spectral modelling. To demonstrate this, we study the spectra of the 'normal' Type Ia supernova (SN Ia) 2005cf between 50 and 350 days after the explosion and identify most of the common SN Ia line features at post-maximum epochs.

  20. The dynamics of neutrino-driven supernova explosions after shock revival in 2D and 3D

    Science.gov (United States)

    Müller, B.

    2015-10-01

    We study the growth of the explosion energy after shock revival in neutrino-driven explosions in two and three dimensions (2D/3D) using multi-group neutrino hydrodynamics simulations of an 11.2 M⊙ star. The 3D model shows a faster and steadier growth of the explosion energy and already shows signs of subsiding accretion after one second. By contrast, the growth of the explosion energy in 2D is unsteady, and accretion lasts for several seconds as confirmed by additional long-time simulations of stars of similar masses. Appreciable explosion energies can still be reached, albeit at the expense of rather high neutron star masses. In 2D, the binding energy at the gain radius is larger because the strong excitation of downward-propagating g modes removes energy from the freshly accreted material in the downflows. Consequently, the mass outflow rate is considerably lower in 2D than in 3D. This is only partially compensated by additional heating by outward-propagating acoustic waves in 2D. Moreover, the mass outflow rate in 2D is reduced because much of the neutrino energy deposition occurs in downflows or bubbles confined by secondary shocks without driving outflows. Episodic constriction of outflows and vertical mixing of colder shocked material and hot, neutrino-heated ejecta due to Rayleigh-Taylor instability further hamper the growth of the explosion energy in 2D. Further simulations will be necessary to determine whether these effects are generic over a wider range of supernova progenitors.

  1. The impact of Type Ia supernova explosions on helium companions in the Chandrasekhar-mass explosion scenario

    CERN Document Server

    Liu, Zheng-Wei; Seitenzahl, Ivo; Hillebrandt, Wolfgang; Kromer, Markus; Roepke, Friedrich; Edelmann, Philipp; Taubenberger, Stefan; Maeda, Keiichi; Wang, Bo; Han, Zhanwen

    2013-01-01

    In the version of the SD scenario of SNe Ia studied here, a CO WD explodes close to the Chandrasekhar limit after accreting material from a non-degenerate He companion. In the present study, we employ the Stellar GADGET code to perform 3D hydrodynamical simulations of the interaction of the SN Ia ejecta with the He companion taking into account its orbital motion and spin. It is found that only 2%--5% of the initial companion mass are stripped off from the outer layers of He companions due to the SN impact. The dependence of the unbound mass (or the kick velocity) on the orbital separation can be fitted in good approximation by a power law for a given companion model. After the SN impact, the outer layers of a He donor star are significantly enriched with heavy elements from the low-expansion-velocity tail of SN Ia ejecta. The total mass of accumulated SN-ejecta material on the companion surface reaches about > 10e-3 M_sun for different companion models. This enrichment with heavy elements provides a potentia...

  2. Type IIb Supernova SN 2011dh: Spectra and Photometry from the Ultraviolet to the Near-Infrared

    CERN Document Server

    Marion, G H "Howie''; Kirshner, Robert P; Foley, Ryan J; Berlind, Perry; Bieryla, Allyson; Bloom, Joshua S; Calkins, Michael L; Challis, Peter; Chevalier, Roger A; Chornock, Ryan; Culliton, Chris; Curtis, Jason L; Esquerdo, Gilbert A; Everett, Mark E; Falco, Emilio E; France, Kevin; Fransson, Claes; Friedman, Andrew S; Garnavich, Peter; Leibundgut, Bruno; Meyer, Samuel; Smith, Nathan; Soderberg, Alicia M; Sollerman, Jesper; Starr, Dan L; Szklenar, Tamas; Takats, Katalin; Wheeler, J Craig

    2013-01-01

    We report spectroscopic and photometric observations of the Type IIb SN 2011dh obtained between 4 and 34 days after the estimated date of explosion (May 31.5 UT). These data cover a wide wavelength range from 2000 Angstroms in the ultraviolet (UV) to 2.4 microns in the near-infrared (NIR). NIR spectra reveal helium in the atmosphere 3 days before the B-band maximum and confirm the classification of SN 2011dh as a Type IIb. Optical spectra provide line profiles and velocity measurements of H I, He I, Ca II and Fe II. UV spectra obtained with the Space Telescope Imaging Spectrograph show that the UV flux for SN 2011dh is low compared to other SN IIb. H I features are strong early and weaken during the period of our observations. He I features are first detected eleven days after the explosion and become progressively stronger. For all phases at which He is detected, the hydrogen line-forming region is separated from the helium layer by about 4000 km/s. This velocity gap is consistent with a H-rich shell surroun...

  3. Explosions of O-Ne-Mg Cores, the Crab Supernova, and Subluminous Type II-P Supernovae

    CERN Document Server

    Kitaura, F S; Hillebrandt, W

    2005-01-01

    We present results of simulations of stellar collapse and explosions in spherical symmetry for progenitor stars in the 8-10 solar mass range with an O-Ne-Mg core. The simulations were continued until nearly one second after core bounce and were performed with the Prometheus/Vertex code with a variable Eddington factor solver for the neutrino transport, including a state-of-the-art treatment of neutrino-matter interactions. Particular effort was made to implement nuclear burning and electron capture rates with sufficient accuracy to ensure a smooth continuation, without transients, from the progenitor evolution to core collapse. Using two different nuclear equations of state (EoSs), a soft version of the Lattimer & Swesty EoS and the significantly stiffer Wolff & Hillebrandt EoS, we found no prompt explosions, but instead delayed explosions, powered by neutrino heating and the neutrino-driven baryonic wind which sets in about 200 ms after bounce. The models eject little nickel ( 0.46, which suggests a ...

  4. Non-thermal emission from supernova shock breakout and the origin of the X-ray transient associated with SN2008D

    CERN Document Server

    Wang, Xiang-Yu; Waxman, Eli; Meszaros, Peter

    2008-01-01

    We suggest that non-thermal emission can be produced by multiple scatterings of the photons between the supernova ejecta and pre-shock material in supernova shock breakout. Such bulk-Comptonization process may significantly change the original thermal photon spectrum, forming a power-law non-thermal component at higher energies. We then show that the luminous X-ray outburst XRO081009 associated with SN2008D is likely to be such shock breakout emission from an ordinary type Ib/c supernova.

  5. Optical photometry and spectroscopy of the low-luminosity, broad-lined Ic supernova iPTF15dld

    DEFF Research Database (Denmark)

    Pian, E.; Tomasella, L.; Cappellaro, E.

    2017-01-01

    Core-collapse stripped-envelope supernova (SN) explosions reflect the diversity of physical parameters and evolutionary paths of their massive star progenitors. We have observed the Type Ic SN iPTF15dld (z = 0.047), reported by the Palomar Transient Factory. Spectra were taken starting 20 rest...

  6. LEGUS Discovery of a Light Echo Around Supernova 2012aw

    NARCIS (Netherlands)

    Van Dyk, S.D.; Lee, J.C.; Anderson, J.; Andrews, J.E.; Calzetti, D.; Bright, S.N.; Ubeda, L.; Smith, L.J.; Sabbi, E.; Grebel, E.K.; Herrero, A.; de Mink, S.E.

    2015-01-01

    We have discovered a luminous light echo around the normal Type II-Plateau Supernova (SN) 2012aw in Messier 95 (M95; NGC 3351), detected in images obtained approximately two years after explosion with the Wide Field Channel 3 on board the Hubble Space Telescope by the Legacy ExtraGalactic

  7. IAUS 331: Supernova 1987A thirty years later

    Science.gov (United States)

    Ray, Alak

    2017-04-01

    First the neutrinos arrived, then the burst of light: messengers of a cataclysmic event in the galaxy next door. Alak Ray recounts IAUS 331, a conference that celebrated the thirtieth anniversary of the supernova of a lifetime, SN1987A, and explored the critical role of asymmetry in the explosions, surroundings and initial conditions.

  8. A Golden Standard Type Ia Supernova SN 2005cf: Observations from the Ultraviolet to the Near-Infrared Wavebands

    CERN Document Server

    Wang, Xiaofeng; Filippenko, Alexei V; Foley, R J; Kirshner, R P; Modjaz, M; Bloom, J; Brown, P J; Carter, D; Friedman, A S; Gal-Yam, A; Ganeshalingam, M; Hicken, M; Krisciunas, K; Milne, P; Suntzeff, N B; Wood-Vasey, W M; Cenko, S B; Challis, P; Fox, D B; Kirkman, D; Li, J Z; Li, T P; Malkan, M A; Reitzel, D B; Rich, R M; Serduke, F; Shang, R C; Silverman, J M; Steele, T N; Swift, B J; Tao, C; Wong, D S; Zhang, S N

    2008-01-01

    We present extensive photometry at ultraviolet (UV), optical, and near-infrared (NIR) wavelengths, as well as dense sampling of optical spectra, for the normal type Ia supernova (SN Ia) 2005cf. From the well-sampled light curves, we find that SN 2005cf reached a B-band maximum at 13.63+/-0.02 mag, with an observed luminosity decline rate dm_15(B) = 1.05+/-0.03 mag. The correlations between the decline rate and various color indexes, recalibrated on the basis of an expanded SN Ia sample, yielded E(B-V)_host=0.09+/-0.03 mag for SN2005cf. The UV photometry was obtained with the HST and the Swift Ultraviolet/Optical Telescope, and the results match each other to within 0.1-0.2 mag. The UV light curves show similar evolution to the broadband U, with an exception in the 2000-2500 Angstrom spectral range (corresponding to the F220W/uvm2 filters), where the light curve appears broader and much fainter than that on either side (likely owing to the intrinsic spectral evolution). Combining the UV data with the ground-ba...

  9. Tycho Brahe's 1572 supernova as a standard typeIa as revealed by its light-echo spectrum

    Science.gov (United States)

    Krause, Oliver; Tanaka, Masaomi; Usuda, Tomonori; Hattori, Takashi; Goto, Miwa; Birkmann, Stephan; Nomoto, Ken'ichi

    2008-12-01

    TypeIa supernovae are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions about supernovae are how the explosion actually proceeds and whether accretion occurs from a companion or by the merging of two white dwarfs. Tycho Brahe's supernova of 1572 (SN1572) is thought to be one of the best candidates for a typeIa supernova in the Milky Way. The proximity of the SN1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. The determination of the hitherto unknown spectroscopic type of this supernova is crucial in relating these results to the diverse population of typeIa supernovae. Here we report an optical spectrum of Tycho's supernova near maximum brightness, obtained from a scattered-light echo more than four centuries after the direct light from the explosion swept past the Earth. We find that SN1572 belongs to the majority class of normal typeIa supernovae.

  10. Tycho Brahe's 1572 supernova as a standard type Ia as revealed by its light-echo spectrum.

    Science.gov (United States)

    Krause, Oliver; Tanaka, Masaomi; Usuda, Tomonori; Hattori, Takashi; Goto, Miwa; Birkmann, Stephan; Nomoto, Ken'ichi

    2008-12-04

    Type Ia supernovae are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions about supernovae are how the explosion actually proceeds and whether accretion occurs from a companion or by the merging of two white dwarfs. Tycho Brahe's supernova of 1572 (SN 1572) is thought to be one of the best candidates for a type Ia supernova in the Milky Way. The proximity of the SN 1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. The determination of the hitherto unknown spectroscopic type of this supernova is crucial in relating these results to the diverse population of type Ia supernovae. Here we report an optical spectrum of Tycho's supernova near maximum brightness, obtained from a scattered-light echo more than four centuries after the direct light from the explosion swept past the Earth. We find that SN 1572 belongs to the majority class of normal type Ia supernovae.

  11. Non-LTE models for synthetic spectra of type Ia supernovae/hot stars with extremely extended atmospheres

    CERN Document Server

    Sauer, D N; Pauldrach, A W A

    2006-01-01

    Realistic atmospheric models that link the properties and the physical conditions of supernova ejecta to observable spectra are required for the quantitative interpretation of observational data of type Ia supernovae (SN Ia) and the assessment of the physical merits of theoretical supernova explosion models. The numerical treatment of the radiation transport - yielding the synthetic spectra - in models of SN Ia ejecta in early phases is usually carried out in analogy to atmospheric models of `normal' hot stars. Applying this analogy indiscriminately leads to inconsistencies in SN Ia models because a diffusive lower boundary, while justified for hot stars, is invalid for hydrogen and helium-deficient supernova ejecta. In type Ia supernovae the radiation field does not thermalize even at large depths, and large optical depths are not reached at all wavelengths. We derive an improved description of the lower boundary that allows a more consistent solution of the radiation transfer in SN Ia and therefore yields m...

  12. First supernova companion star found

    Science.gov (United States)

    2004-01-01

    Supernova 1993J exploding hi-res Size hi-res: 222 kb Credits: ESA and Justyn R. Maund (University of Cambridge) Supernova 1993J exploding (artist’s impression) New observations with the Hubble Space Telescope allow a look into a supernova explosion under development. In this artist’s view the red supergiant supernova progenitor star (left) is exploding after having transferred about 10 solar masses of hydrogen gas to the blue companion star (right). This interaction process happened over about 250 years and affected the supernova explosion to such an extent that SN 1993J was later known as one of the most peculiar supernovae ever seen. Supernova 1993J exploding hi-res Size hi-res: 4200 kb Credits: ESA and Justyn R. Maund (University of Cambridge) The site of the Supernova 1993J explosion A virtual journey into one of the spiral arms of the grand spiral Messier 81 (imaged with the Isaac Newton Telescope on La Palma, left) reveals the superb razor-sharp imaging power of the NASA/ESA Hubble Space Telescope (Hubble’s WFPC2 instrument, below). The close-up (with Hubble’s ACS, to the right) is centred on the newly discovered companion star to Supernova 1993J that itself is no longer visible. The quarter-circle around the supernova companion is a so-called light echo originating from sheets of dust in the galaxy reflecting light from the original supernova explosion. Supernova 1993J explosing site hi-res Size hi-res: 1502 kb Credits: ESA and Justyn R. Maund (University of Cambridge) Close-up of the Supernova 1993J explosion site (ACS/HRC image) This NASA/ESA Hubble Space Telescope image shows the area in Messier 81 where Supernova 1993J exploded. The companion to the supernova ‘mother star’ that remains after the explosion is seen in the centre of the image. The image is taken with Hubble’s Advanced Camera for Surveys and is a combination of four exposures taken with ACS’ High Resolution Camera. The exposures were taken through two near-UV filters (250W

  13. SN 2010jl in UGC 5189: Yet another luminous type IIn supernova in a metal-poor galaxy

    CERN Document Server

    Stoll, R; Stanek, K Z; Pogge, R W; Szczygiel, D M; Pojmanski, G; Antognini, J; Yan, H

    2010-01-01

    We present ASAS data starting 25 days before the discovery of the recent type IIn SN 2010jl, and we compare its light curve to other luminous IIn SNe, showing that it is a luminous (M_I ~ -20.5) event. Its host galaxy, UGC 5189, has a low gas-phase oxygen abundance (12 + log(O/H) = 8.2), which reinforces the emerging trend that over-luminous core-collapse supernovae are found in the low-metallicity tail of the galaxy distribution, similar to the known trend for the hosts of long GRBs. We compile oxygen abundances from the literature and from our own observations of UGC 5189, and we present an unpublished spectrum of the luminous type Ic SN 2010gx that we use to estimate its host metallicity. We discuss these in the context of host metallicity trends for different classes of core-collapse objects. The earliest generations of stars are known to be enhanced in [O/Fe] relative to the Solar mixture; it is therefore likely that the stellar progenitors of these overluminous supernovae are even more iron-poor than th...

  14. 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.

  15. LOSS'S First Supernova: New Limits on the "Impostor" SN 1997bs

    CERN Document Server

    Adams, Scott M

    2015-01-01

    We present new, late-time Hubble Space Telescope and Spitzer Space Telescope observations of the archetypal SN impostor SN 1997bs. We show that SN 1997bs remains much fainter than its progenitor, ruling out the canonical picture of late-time obscuration by dust forming in a shell ejected during the transient. The possibility that the star survived cloaked behind a dusty, steady wind is also disfavored. The simplest explanation is that SN 1997bs was a subluminous Type IIn SN, although it is impossible to rule out the possibility that the star survived, but with a significantly decreased intrinsic luminosity.

  16. The supernova rate: a critical ingredient and an important tool

    CERN Document Server

    Mannucci, F

    2009-01-01

    In this review I summarize the role of supernova rate as a critical ingredient of modern astrophysics, and as an important tool to understand SN explosions. Many years of active observations and theoretical modeling have produced several important results. In particular, linking SN rates with parent stellar populations has proved to be an important strategy. Despite these advances, the situation is far from clear, in particular for the SNe Ia.

  17. Star formation triggered by SN explosions: an application to the stellar association of $\\beta$ Pictoris

    CERN Document Server

    Melioli, C; De la Reza, R; Raga, A

    2006-01-01

    In the present study, considering the physical conditions that are relevant in interactions between supernova remnants (SNRs) and dense molecular clouds for triggering star formation we have built a diagram of SNR radius versus cloud density in which the constraints above delineate a shaded zone where star formation is allowed. We have also performed fully 3-D radiatively cooling numerical simulations of the impact between SNRs and clouds under different initial conditions in order to follow the initial steps of these interactions. We determine the conditions that may lead either to cloud collapse and star formation or to complete cloud destruction and find that the numerical results are consistent with those of the SNR-cloud density diagram. Finally, we have applied the results above to the $\\beta-$Pictoris stellar association which is composed of low mass Post-T Tauri stars with an age of 11 Myr. It has been recently suggested that its formation could have been triggered by the shock wave produced by a SN e...

  18. Very Early Photometry of SN 1998S: Physical Parameters and Date of Explosion

    CERN Document Server

    Poon, H; Lam, T Y; Qiu, Y L; Wei, J Y

    2011-01-01

    Context. We present very early optical lightcurves beginning 10 days before maximum of the Type IIn supernova 1998S, covering the first four months after discovery. Aims. We examine the light evolution and try to compare the lightcurves to two analytical models(Nakar & Sari(2010) and Rabinak & Waxman(2011)) for a red supergiant star. Methods. The photometry was carried at the 60-cm telescope of the Xinglong Station of China. Broadband filters Johnsons B, V and Cousins R were used. Results. The magnitude rose for the first few days and then dropped slowly afterwards. The two di?erent models we use can fit the early lightcurves very well. The explosion date derived from the models is within the range of 1998 March 1.34 - 2.64(JD 2450873.84 - JD 2450875.14.) The radius of the progenitor is found to be ~ 300 Rsun and ~ 2000 Rsun for the model of Nakar & Sari(2010) and Rabinak & Waxman(2011) respectively. The constraint on mass and energy is not strong. The ranges of these two parameters are within...

  19. Cepheid Calibration of the Peak Brightness of Type Ia Supernovae. XI. SN 1998aq in NGC 3982

    Science.gov (United States)

    Saha, A.; Sandage, Allan; Tammann, G. A.; Dolphin, A. E.; Christensen, J.; Panagia, N.; Macchetto, F. D.

    2001-11-01

    Repeated imaging observations have been made of NGC 3982 with the Hubble Space Telescope between 2000 March and May, over an interval of 53 days. Images were obtained on 12 epochs in the F555W band and on five epochs in the F814W band. The galaxy hosted the Type Ia supernova (SN Ia) SN 1998aq. A total of 26 Cepheid candidates were identified, with periods ranging from 10 to 45 days, using photometry with the DoPHOT program. The dereddened distance to NGC 3982 is estimated from these data using various criteria to maximize signal-to-noise ratio and reliability: the values lie between 31.71 and 31.82, with uncertainties in the mean of typically +/-0.14 mag for each case. A parallel analysis using photometry with HSTphot discovered 13 variables, yielding a distance modulus of 31.85+/-0.16. The final adopted modulus is (M-m)0=31.72+/-0.14 (22+/-1.5 Mpc). Photometry of SN 1998aq that is available in the literature is used in combination with the derived distance to NGC 3982 to obtain the peak absolute magnitude of this supernova. The lower limit (no extinction within the host galaxy) for MV is -19.47+/-0.15 mag. Corrections for decline rate and intrinsic color to carry these to the reduced system of Parodi and collaborators have been performed. The derived luminosities at hand are fully consistent with the mean of the eight normal SNe Ia previously calibrated with Cepheids. Together they yield H0~60+/-2(internal) km s-1 Mpc-1 based on an assumed LMC distance modulus of 18.50. We point out that correcting some of the systematic errors and including uncertainty estimates due to them leads to H0=58.7+/-6.3(internal) km s-1 Mpc-1.

  20. Cepheid Calibration of the Peak Brightness of Type IA Supernovae. VI. SN 1960F in NGC 4496A

    Science.gov (United States)

    Saha, A.; Sandage, Allan; Labhardt, Lukas; Tammann, G. A.; Macchetto, F. D.; Panagia, N.

    1996-12-01

    Cepheid variables have been found in the SBcII galaxy NGC 4496A, parent to the Type Ia supernova 1960F. Of the 130 variables discovered with the Hubble Space Telescope (HST) over a 70 day observing internal from 1994 June to August, comprising 17 epochs in the F555W band and four epochs in the F814W band, 95 are bona fide Cepheids. The periods range from 7 days to greater than 70 days, with the mean magnitudes ranging from = 24.4 to 26.8. The distance modulus of NGC 4496A, based on the Cepheids, is (rn-Al)0 = 31.03±0.14, where a formal reddening of E(V-I) = 0.04±0.06 derived from the colors of the Cepheids has been used to account for possible extinction. There is no measurable differential reddening over the field. The absolute magnitudes of SN 1960F at maximum are M(B)max = -19.43±0.17 and M(V)max =-19.52±0.21. Combining these absolute magnitudes with the Hubble diagrams of "Branch normal" Type Ia supernovae (SNe Ia), determined earlier, gives Hubble constants, based on SN 1960F alone, of HO(B)=56±9 km s-1, (1) and H0(V) = 55±9 km s-1. (2) Combining the calibration of SN 1960F here with six other extant calibrations set out in Paper VII gives interim mean absolute magnitude calibrations of M(B) = -19.45±0.07 and 4M(V) max = -19.47±0.07, with no evidence for appreciable dependence on the light-curve decay rate. These mean interim calibrations require H0(B) = 57±4 km s-1 and H0(V) = 58±4 km s-1 Mpc-1.

  1. Optical and near infrared observations of SN 2014ck: an outlier among the Type Iax supernovae

    CERN Document Server

    Tomasella, L; Benetti, S; Pastorello, A; Hsiao, E Y; Sand, D J; Stritzinger, M; Valenti, S; McCully, C; Arcavi, I; Elias-Rosa, N; Harmanen, J; Harutyunyan, A; Hosseinzadeh, G; Howell, D A; Kankare, E; Morales-Garoffolo, A; Taddia, F; Tartaglia, L; Terreran, G; Turatto, M

    2016-01-01

    We present a comprehensive set of optical and near-infrared photometric and spectroscopic observations for SN 2014ck, extending from pre-maximum to six months later. These data indicate that SN 2014ck is photometrically nearly identical to SN 2002cx, which is the prototype of the class of peculiar transients named SNe Iax. Similar to SN 2002cx, SN 2014ck reached a peak brightness $M_B=-17.37 \\pm 0.15$ mag, with a post-maximum decline-rate $\\Delta m_{15} (B) = 1.76 \\pm 0.15$ mag. However, the spectroscopic sequence shows similarities with SN 2008ha, which was three magnitudes fainter and faster declining. In particular, SN 2014ck exhibits extremely low ejecta velocities, $\\sim 3000$ km s$^{-1}$ at maximum, which are close to the value measured for SN 2008ha and half the value inferred for SN 2002cx. The bolometric light curve of SN 2014ck is consistent with the production of $0.10^{+0.04}_{-0.03} M_{\\odot}$ of $^{56}$Ni. The spectral identification of several iron-peak features, in particular Co II lines in th...

  2. 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.

  3. 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...

  4. 2D radiaition-hydrodynamic simulations of supernova shock breakout in bipolar explosions of a blue supergiant progenitor

    CERN Document Server

    Suzuki, Akihiro; Shigeyama, Toshikazu

    2016-01-01

    A two-dimensional special relativistic radiation-hydrodynamics code is developed and applied to numerical simulations of supernova shock breakout in bipolar explosions of a blue supergiant. Our calculations successfully simulate the dynamical evolution of a blast wave in the star and its emergence from the surface. Results of the model with spherical energy deposition show a good agreement with previous simulations. Furthermore, we calculate several models with bipolar energy deposition and compare their results with the spherically symmetric model. The bolometric light curves of the shock breakout emission are calculated by a ray-tracing method. Our radiation-hydrodynamic models indicate that the early part of the shock breakout emission can be used to probe the geometry of the blast wave produced as a result of the gravitational collapse of the iron core.

  5. 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.

  6. SUPERNOVA 1987A: CELEBRATING A SILVER JUBILEE

    Directory of Open Access Journals (Sweden)

    Nino Panagia

    2013-12-01

    Full Text Available The story of the SN 1987A explosion is briefly reviewed. Although this supernova was somewhat peculiar, the study of SN 1987A has clarified quite a number of important aspects of the nature and the properties of supernovae, such as the confirmation of the core collapse of a massive star as the cause of the explosion, as well the confirmation that the decays 56Ni–56Co–56Fe at early times and 44Ti–44Sc at late times, are the main sources of the energy radiated by the ejecta. Still we have not been able to ascertain whether the progenitor was a single star or a binary system, nor have we been able to detect the stellar remnant, a neutron star that should be produced in the core collapse process.

  7. Spectroscopy of supernova host galaxies from the SDSS-II SN survey with the SDSS and BOSS spectrographs

    Science.gov (United States)

    Olmstead, Matthew Dwaune

    Type Ia supernovae (SNeIa) have been used as standard candles to measure cosmological distances. The initial discovery of the accelerated expansion of the universe was performed using ~50 SNe Ia. Large SNe surveys have increased the number of spectroscopically-confirmed SNe Ia to over a thousand with redshift coverage beyond z = 1. We are now in the age of abundant photometry without the ability for full follow-up spectroscopy of all SN candidates. SN cosmology using these large samples will increasingly rely on robust photometric classification of SN candidates. Photometric classification will increase the sample by including faint SNe as these are preferentially not observed with follow-up spectroscopy. The primary concern with using photometrically classified SNe Ia in cosmology is when a core-collapse SNe is incorrectly classified as an SN Ia. This can be mitigated by obtaining the host galaxy redshift of each SN candidate and using this information as a prior in the photometric classification, removing one degree of freedom. To test the impact of redshift on photometric classification, I have performed an assessment on photometric classification of candidates from the Sloan Digital Sky Survey-II (SDSS-II) SN Survey. I have tested the classification with and without redshift priors by looking at the change of photometric classification, the effect of data quality on photometric classification, and the effect of SN light curve properties on photometric classification. Following our suggested classification scheme, there are a total of 1038 photometrically classified SNe Ia when using a flat redshift prior and 1002 SNe~Ia with the spectroscopic redshift. For 912 (91.0%) candidates classified as likely SNe Ia without redshift information, the classification is unchanged when adding the host galaxy redshift. Finally, I investigate the differences in the interpretation of the light curve properties with and without knowledge of the redshift. When using the SALT2

  8. On the Nature of Type Ia-CSM Supernovae: Optical and Near-Infrared Spectra of SN 2012ca and SN 2013dn

    CERN Document Server

    Fox, Ori D; Filippenko, Alexei V; Mauerhan, Jon; Becker, Juliette; Borish, H Jacob; Cenko, S Bradley; Clubb, Kelsey I; Graham, Melissa; Hsiao, Eric; Kelly, Patrick L; Lee, William H; Marion, G H; Milisavljevic, Dan; Parrent, Jerod; Shivvers, Isaac; Skrutskie, Michael; Smith, Nathan; Wilson, John; Zheng, Weikang

    2014-01-01

    A growing subset of Type Ia supernovae (SNe Ia) show evidence for unexpected interaction with a dense circumstellar medium (SNe Ia-CSM). The precise nature of the progenitor, however, remains debated owing to spectral ambiguities arising from a strong contribution from the CSM interaction. Late-time spectra offer potential insight if the post-shock cold, dense shell becomes sufficiently thin and/or the ejecta begin to cross the reverse shock. To date, few high-quality spectra of this kind exist. Here we report on the late-time optical and infrared spectra of the SNe~Ia-CSM 2012ca and 2013dn. These SNe Ia-CSM spectra exhibit low [Fe III]/[Fe II] ratios and strong [Ca II] at late epochs. Such characteristics are reminiscent of the super-Chandrasekhar-mass (SC) candidate SN 2009dc, for which these features suggested a low-ionisation state due to high densities, although the broad Fe features admittedly show similarities to the blue "quasi-continuum" observed in some core-collapse SNe Ibn and IIn. Neither SN 2012...

  9. SN 2009kn - the twin of the Type IIn supernova 1994W

    DEFF Research Database (Denmark)

    Kankare, E.; Ergon, M.; Bufano, F.;

    2012-01-01

    . Contrarily, the photometric evolution resembles more that of a Type IIP SN with a large drop in luminosity at the end of the plateau phase. These characteristics are similar to those of SN 1994W, whose nature has been explained with two different models with different approaches. The well-sampled data set...

  10. A panchromatic view of the restless SN2009ip reveals the explosive ejection of a massive star envelope

    CERN Document Server

    Margutti, R; Soderberg, A M; Chornock, R; Zauderer, B A; Murase, K; Guidorzi, C; Sanders, N E; Kuin, P; Fransson, C; Levesque, E M; Chandra, P; Berger, E; Bianco, F B; Brown, P J; Challis, P; Chatzopoulos, E; Cheung, C C; Choi, C; Chomiuk, L; Chugai, N; Contreras, C; Drout, M R; Fesen, R; Foley, R J; Fong, W; Friedman, A S; Gall, C; Gehrels, N; Hjorth, J; Hsiao, E; Kirshner, R; Im, M; Leloudas, G; Lunnan, R; Marion, G H; Martin, J; Morrell, N; Neugent, K F; Omodei, N; Phillips, M M; Rest, A; Silverman, J M; Strader, J; Stritzinger, M D; Szalai, T; Utterback, N B; Vinko, J; Wheeler, J C; Arnett, D; Campana, S; Chevalier, R; Ginsburg, A; Kamble, A; Roming, P W A; Pritchard, T; Stringfellow, G

    2013-01-01

    The 2012 explosion of SN2009ip raises questions about our understanding of the late stages of massive star evolution. Here we present a comprehensive study of SN2009ip during its remarkable re-brightening(s). High-cadence photometric and spectroscopic observations from the GeV to the radio band obtained from a variety of ground-based and space facilities (including the VLA, Swift, Fermi, HST and XMM) constrain SN2009ip to be a low energy (E~ 10^50 erg for an ejecta mass ~ 0.5 Msun) and likely asymmetric explosion in a complex medium shaped by multiple eruptions of the restless progenitor star. Most of the energy is radiated as a result of the shock breaking out through a dense shell of material located at 5x10^14 cm with M~0.1 Msun, ejected by the precursor outburst ~40 days before the major explosion. We interpret the NIR excess of emission as signature of dust vaporization of material located further out (R>4x 10^15 cm), the origin of which has to be connected with documented mass loss episodes in the previ...

  11. No evidence for an early seventeenth-century Indian sighting of Keplers supernova (SN1604)

    CERN Document Server

    van Gent, Robert H

    2012-01-01

    In a recent paper Sule et al. (Astronomical Notes, vol. 332 (2011), 655) argued that an early 17th-century Indian mural of the constellation Sagittarius with a dragon-headed tail indicated that the bright supernova of 1604 was also sighted by Indian astronomers. In this paper it will be shown that this identification is based on a misunderstanding of traditional Islamic astrological iconography and that the claim that the mural represents an early 17th-century Indian sighting of the supernova of 1604 has to be rejected.

  12. No evidence for an early seventeenth-century Indian sighting of Kepler's supernova (SN1604)

    Science.gov (United States)

    van Gent, R. H.

    2013-03-01

    In a recent paper in this journal, Sule et al. (2011) argued that an early 17th-century Indian mural of the constellation Sagittarius with a dragon-headed tail indicated that the bright supernova of 1604 was also sighted by Indian astronomers. In this paper it will be shown that this identification is based on a misunderstanding of traditional Islamic astrological iconography and that the claim that the mural represents an early 17th-century Indian sighting of the supernova of 1604 has to be rejected.

  13. Parametrized 3D models of neutrino-driven supernova explosions: Neutrino emission asymmetries and gravitational-wave signals

    CERN Document Server

    Müller, E; Wongwathanarat, A

    2011-01-01

    Time-dependent and direction-dependent neutrino and gravitational-wave (GW) signatures are presented for a set of 3D hydrodynamic models of parametrized, neutrino-driven supernova explosions of non-rotating 15 and 20 solar mass stars. We employ an approximate treatment of neutrino transport. Due to the excision of the high-density core of the proto-neutron star and the use of an axis-free overset grid, the models can be followed from the post-bounce accretion phase for more than one second without imposing any symmetry restrictions. GW and neutrino emission exhibit the generic time-dependent features known from 2D models. Non-radial hydrodynamic mass motions in the accretion layer and their interaction with the outer layers of the proto-neutron star together with anisotropic neutrino emission give rise to a GW signal with an amplitude of ~5-20 cm and frequencies 100--500 Hz. The GW emission from mass motions reaches a maximum before the explosion sets in. Afterwards the GW signal exhibits a low-frequency modu...

  14. Two Dimensional Core-Collapse Supernova Explosions Aided by General Relativity with Multidimensional Neutrino Transport

    CERN Document Server

    O'Connor, Evan

    2015-01-01

    We present results from computational simulations of core-collapse supernovae in {\\tt FLASH} using a newly-implemented multidimensional neutrino transport scheme and a newly-implemented general relativistic (GR) treatment of gravity. For the neutrino transport, we use a two moment method with an analytic closure (so-called M1 transport). This transport is multienergy, multispecies and truly multidimensional since we do not assume the commonly used ray-by-ray approximation. Our GR gravity is implemented in our Newtonian hydrodynamics simulations via an effective relativistic potential that closely reproduces the GR structure of neutron stars and has been shown to match GR simulations of core collapse quite well. In axisymmetry, we simulate core-collapse supernovae with five different progenitor models in both Newtonian and GR gravity. We find that the more compact protoneutron star structure realized in simulations with GR gravity gives higher neutrino luminosities and higher neutrino energies. These differenc...

  15. Gravitational-Wave Bursts Induced by Neutrino Oscillations: The Origin of Asymmetry in Supernovae Explosions

    OpenAIRE

    Cuesta, Herman J. Mosquera

    1999-01-01

    If neutrino flavor changes really exist, to say: $\\mu$-neutrino oscillating into a sterile neutrino, then, it can be expected that due to neutrino oscillations and non-spherical distortion of the resonance surface induced by the magnetic field, some asymmetric emission of sterile neutrinos can occur during the protoneutron star formation at the onset of a supernova core-collapse. Assuming no strong suppression of the oscillations, the non-spherical huge neutrino energies released, ($\\sim 10^{...

  16. EmpiriciSN: Re-sampling Observed Supernova/Host Galaxy Populations using an XD Gaussian Mixture Model

    CERN Document Server

    Holoien, Thomas W -S; Wechsler, Risa H

    2016-01-01

    We describe two new open source tools written in Python for performing extreme deconvolution Gaussian mixture modeling (XDGMM) and using a conditioned model to re-sample observed supernova and host galaxy populations. XDGMM is new program for using Gaussian mixtures to do density estimation of noisy data using extreme deconvolution (XD) algorithms that has functionality not available in other XD tools. It allows the user to select between the AstroML (Vanderplas et al. 2012; Ivezic et al. 2015) and Bovy et al. (2011) fitting methods and is compatible with scikit-learn machine learning algorithms (Pedregosa et al. 2011). Most crucially, it allows the user to condition a model based on the known values of a subset of parameters. This gives the user the ability to produce a tool that can predict unknown parameters based on a model conditioned on known values of other parameters. EmpiriciSN is an example application of this functionality that can be used for fitting an XDGMM model to observed supernova/host datas...

  17. 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...

  18. No Evidence for an Early Seventeenth-Century Indian Sighting of Kepler's Supernova (SN1604)

    NARCIS (Netherlands)

    van Gent, R. H.

    2013-01-01

    In a recent paper in this journal, Sule et al. (2011) argued that an early 17th-century Indian mural of the constellation Sagittarius with a dragon-headed tail indicated that the bright supernova of 1604 was also sighted by Indian astronomers. In this paper it will be shown that this identification

  19. Observational and Physical Classification of Supernovae

    CERN Document Server

    Gal-Yam, Avishay

    2016-01-01

    This chapter describes the current classification scheme of supernovae (SNe). This scheme has evolved over many decades and now includes numerous SN Types and sub-types. Many of these are universally recognized, while there are controversies regarding the definitions, membership and even the names of some sub-classes; we will try to review here the commonly-used nomenclature, noting the main variants when possible. SN Types are defined according to observational properties; mostly visible-light spectra near maximum light, as well as according to their photometric properties. However, a long-term goal of SN classification is to associate observationally-defined classes with specific physical explosive phenomena. We show here that this aspiration is now finally coming to fruition, and we establish the SN classification scheme upon direct observational evidence connecting SN groups with specific progenitor stars. Observationally, the broad class of Type II SNe contains objects showing strong spectroscopic signat...

  20. The GRB060218/SN 2006aj link to Supernova-GRBs blazing and re-brightening by precessing showering Jets

    CERN Document Server

    Fargion, D

    2006-01-01

    A list of puzzles are unanswered by Fireball (even milli-steradiant beamed) explosive GRB and Magnetar spherical one-shoot SGR models. The early GRB 980425 and the last longest GRB060218 are the most emblematic GRBs out of the tune of any Fireball cone models. Too nearby, too soft, too underluminous and too long events. The huge flare of SGR 1806-20 and its radio rebrightening disagree with Magnetar model. Only a persistent, thin (even less than micro steradiant) precessing and spinning gamma jet evolution explains X-gamma time structure and afterglow bumps. The late relic neutron star, X-ray pulsar jet, its spinning and precessing lepton-gamma jet is the candidate blazing sources as anomalous X-ray Pulsars (AXRPs) and Soft Gamma-Ray Repeaters (SGRs). Precessing jet are like SS433 spiral jets. At SN power and in-axis they are GRBs. Late (weeks-months) GRB blazing jets are seldom orphan of their bright SN-OT. The last GRB060218 occurred within its SN2006aj smoothly and soft (because off-axis), ruled by outer j...

  1. A luminous, blue progenitor system for a type-Iax supernova

    CERN Document Server

    McCully, Curtis; Foley, Ryan J; Bildsten, Lars; Fong, Wen-fai; Kirshner, Robert P; Marion, G H; Riess, Adam G; Stritzinger, Maximilian D

    2014-01-01

    Type-Iax supernovae (SN Iax) are stellar explosions that are spectroscopically similar to some type-Ia supernovae (SN Ia) at maximum light, except with lower ejecta velocities. They are also distinguished by lower luminosities. At late times, their spectroscopic properties diverge from other SN, but their composition (dominated by iron-group and intermediate-mass elements) suggests a physical connection to normal SN Ia. These are not rare; SN Iax occur at a rate between 5 and 30% of the normal SN Ia rate. The leading models for SN Iax are thermonuclear explosions of accreting carbon-oxygen white dwarfs that do not completely unbind the star, implying they are "less successful" cousins of normal SN Ia, where complete disruption is observed. Here we report the detection of the luminous, blue progenitor system of the type-Iax SN 2012Z in deep pre-explosion imaging. Its luminosity, colors, environment, and similarity to the progenitor of the Galactic helium nova V445 Puppis, suggest that SN 2012Z was the explosio...

  2. Cepheid Calibration of the Peak Brightness of Type IA Supernovae: Calibration of SN 1990N in NGC 4639 Averaged with Six Earlier Type IA Supernova Calibrations to Give H 0 Directly

    Science.gov (United States)

    Sandage, Allan; Saha, A.; Tammann, G. A.; Labhardt, Lukas; Panagia, N.; Macchetto, F. D.

    1996-03-01

    Periods and light curves have been measured with the Hubble Space Telescope for 20 Cepheids in NGC 4639, parent galaxy to the Type Ia, prototypical supernova SN 1990N. The periods range from 17 to 69 days. The mean apparent magnitudes, averaged over the light curves, range from = 25.6 to = 27.3. Well-determined period-luminosity relations exist in V and I. Corrected for differential extinction, these give a true modulus for NGC 4639 of (m - M)0 = 32.00 +/- 0.23. Combining the light curves for SN 1990N with this modulus gives MB(max) = -19.30 +/- 0.23 and MV(max) = -19.39 +/- 0.23. This, together with six previous calibrations of Type Ia supernovae, gives the mean calibrations of "Branch normal" supernovae to date as = -19.47 +/- 0.07 and = -19.48 +/- 0.07. The resulting Hubble constants, reading the Type Ia supernova Hubble diagrams at very large redshifts beyond any possible local velocity anomalies, give global values of the Hubble constant of H0(B) = 56 +/- 4 (internal) km s-1 Mpc-1 and H0(V) = 58 +/- 4 (internal) km s-1 Mpc-1.

  3. SALT spectroscopic classification of ASASSN-16cc (SN 2016aqf) as a type-II supernova

    Science.gov (United States)

    Jha, S. W.; Miszalski, B.

    2016-02-01

    We obtained SALT (+RSS) spectroscopy of ASASSN-16cc (SN 2016aqf) on 2016 February 27.9 UT, covering the wavelength range 360-920 nm. The spectrum features a blue continuum with prominent P-Cygni lines of H and He. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows a good match to the type-IIP SN 2014et at -3 days, confirming the results of Hosseinzadeh et al. (ATel 8748).

  4. Nebular spectra and abundance tomography of the type Ia supernova SN 2011fe: a normal SN Ia with a stable Fe core

    CERN Document Server

    Mazzali, P A; Filippenko, A V; Garnavich, P M; Clubb, K I; Maguire, K; Pan, Y -C; Shappee, R; Silverman, J M; Benetti, S; Hachinger, S; Nomoto, K; Pian, E

    2015-01-01

    A series of optical and one near-infrared nebular spectra covering the first year of the Type Ia supernova SN 2011fe are presented and modelled. The density profile that proved best for the early optical/ultraviolet spectra, "rho-11fe", was extended to lower velocities to include the regions that emit at nebular epochs. Model rho-11fe is intermediate between the fast deflagration model W7 and a low-energy delayed-detonation. Good fits to the nebular spectra are obtained if the innermost ejecta are dominated by neutron-rich, stable Fe-group species, which contribute to cooling but not to heating. The correct thermal balance can thus be reached for the strongest [FeII] and [FeIII] lines to be reproduced with the observed ratio. The 56Ni mass thus obtained is 0.47 +/- 0.05 Mo. The bulk of 56Ni has an outermost velocity of ~8500 km/s. The mass of stable iron is 0.23 +/- 0.03 Mo. Stable Ni has low abundance, ~10^{-2} Mo. This is sufficient to reproduce an observed emission line near 7400 A. A sub-Chandrasekhar exp...

  5. Predictions for signatures of the quark-nova in superluminous supernovae

    CERN Document Server

    Ouyed, Rachid; Jaikumar, Prashanth

    2009-01-01

    [Abridged] Superluminous Supernovae (SN2006gy, SN2005gj, SN2005ap, SN2008fz, SN2003ma) have been a challenge to explain by standard models. We present an alternative scenario involving a quark-nova (QN), an explosive transition of the newly born neutron star to a quark star in which a second explosion (delayed) occurs inside the already expanding ejecta of a normal SN. The reheated SN ejecta can radiate at higher levels for longer periods of time primarily due to reduced adiabatic expansion losses, unlike the standard SN case. Our model is successfully applied to SN2006gy, SN2005gj, SN2005ap, SN2008fz, SN2003ma with encouraging fits to the lightcurves. There are four predictions in our model: (i) superluminous SNe optical lightcurves should show a double-hump with the SN hump at weaker magnitudes occurring days to weeks before the QN; (ii) Two shock breakouts should be observed vis-a-vis one for a normal SN. Depending on the time delay, this would manifest as two distinct spikes in the X-ray region or a broad...

  6. Swift Observations of Supernovae during and after Shock Breakout

    Science.gov (United States)

    Immler, Stefan

    2008-01-01

    Over the past few years, space-based observatories have allowed detailed studies of energetic supernova explosions in previously unexplored time domains and wavelength regimes. NASA's Swift observatory is playing an important role in probing the early emission of SNe during and after shock breakout due to its fast response, flexible scheduling capabilities, and large wavelength band coverage, ranging from the optical, W, and X-ray to the Gamma-ray bands. By studying the outgoing SN shocks with material in its surroundings, the explosion physics and nature of progenitor stars can be studied. Furthermore, monitoring the X-ray emission of SNe with space-based X-ray observatories is being used to map the density structure in SN environments out to large radii from the sites of the explosions (>E20 cm), the transition of a SN into an old supernova remnant can be studied, and the mass-loss rates of the progenitor stars are being probed over significant timescales (>E4 years) in the stellar wind history. In combination, these observations give unprecedented insights into the nature of energetic explosions and their environments. During this talk, I will present highlights from recent observations, among them the first observation of a SN DURING the actual explosion with Swift, and I will discuss the "naked eye" burst at a redshift of -1, which was the most distant object humans could ever see with their own eyes.

  7. Spectroscopic Classification of SN 2017coa as a Type Ia Supernova

    Science.gov (United States)

    Xiang, Danfeng; Rui, Liming; Wang, Xiaofeng; Tan, Hanjie; Li, Wenxiong; Zhang, Tianmeng; Xu, Zhijian; Yang, Zesheng; Song, Hao; Mo, Jun; Wang, Yuanhao; Zhou, Ziheng; Meng, Xianmin; Qian, Shenban; Jia, Junjun; Zhou, Xu; Zhang, Jujia

    2017-04-01

    We obtained an optical spectrum (range 360-840 nm) of SN 2017coa,discovered by Tsinghua-NAOC Transient Survey (TNTS), on UT Mar.31.49 2017 with the 2.16-m telescope (+BFOSC) at Xinglong Station of National Astronomical Observatories of China (NAOC).

  8. Spectroscopic Classification of SN 2017yi as a Type Ia Supernova

    Science.gov (United States)

    Rui, Liming; Wang, Xiaofeng; Xiang, Danfeng; Li, Wenxiong; Jia, Junjun; He, Min; Zhang, Tianmeng; Wu, Zhenyu; Zhang, Jujia

    2017-02-01

    We obtained an optical spectrum (range 370-850 nm) of SN 2017yi, discovered by J. Vales,on UT Feb.01.5 2017 with the 2.16-m telescope (+BFOSC) at Xinglong Station of National Astronomical Observatories of China (NAOC).

  9. Spectroscopic classification of Gaia16cdi (SN 2016iyf) as Type Ia supernova with SEDM

    Science.gov (United States)

    Blagorodnova, N.; Neill, James D.; Walters, R.

    2016-12-01

    The Caltech Time Domain Astronomy group reports the classification of Gaia16cdi (SN 2016iyf), discovered by the Gaia ESA survey. The follow-up spectroscopic observations were performed with the Spectral Energy Distribution Machine (SEDM) (http://www.astro.caltech.edu/sedm/, range 350-950nm, spectral resolution R 100) on Palomar 60-inch (P60) telescope.

  10. Cosmic ray electrons and positrons from supernova explosions of massive stars.

    Science.gov (United States)

    Biermann, P L; Becker, J K; Meli, A; Rhode, W; Seo, E S; Stanev, T

    2009-08-07

    We attribute the recently discovered cosmic ray electron and cosmic ray positron excess components and their cutoffs to the acceleration in the supernova shock in the polar cap of exploding Wolf-Rayet and red supergiant stars. Considering a spherical surface at some radius around such a star, the magnetic field is radial in the polar cap as opposed to most of 4pi (the full solid angle), where the magnetic field is nearly tangential. This difference yields a flatter spectrum, and also an enhanced positron injection for the cosmic rays accelerated in the polar cap. This reasoning naturally explains the observations. Precise spectral measurements will be the test, as this predicts a simple E;{-2} spectrum for the new components in the source, steepened to E;{-3} in observations with an E;{-4} cutoff.

  11. SALT spectroscopic classification of LSQ16acz (= PS16bby = SN 2016bew) as a type-Ia supernova approaching maximum light

    Science.gov (United States)

    Jha, S. W.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Kotze, M.

    2016-03-01

    We obtained SALT (+RSS) spectroscopy of LSQ16acz (= PS16bby = SN 2016bew; Baltay et al. 2013, PASP, 125, 683) on 2016 Mar 14.9 UT, covering the wavelength range 340-920 nm. Cross-correlation of the spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows LSQ16acz is a type-Ia supernova a few days before maximum light.

  12. Ultra-stripped supernovae and double neutron star systems

    CERN Document Server

    Tauris, Thomas

    2015-01-01

    The evolution of close-orbit progenitor binaries of double neutron star (DNS) systems leads to supernova (SN) explosions of ultra-stripped stars. The amount of SN ejecta mass is very limited from such, more or less, naked metal cores with envelope masses of only 0.01-0.2 Msun. The combination of little SN ejecta mass and the associated possibility of small NS kicks is quite important for the characteristics of the resulting DNS systems left behind. Here, we discuss theoretical predictions for DNS systems, based on Case BB Roche-lobe overflow prior to ultra-stripped SNe, and briefly compare with observations.

  13. Type Ia supernovae within dense carbon-oxygen rich envelopes: a model for 'Super-Chandrasekhar' explosions?

    CERN Document Server

    Noebauer, U M; Blinnikov, S; Sorokina, E; Hillebrandt, W

    2016-01-01

    We investigate the consequences of fairly normal Type Ia supernovae being embedded in compact and dense envelopes of carbon and oxygen rich circumstellar material by means of detailed radiation hydrodynamic simulations. Our main focus rests on exploring the effects of the interaction between ejecta and circumstellar material on the ejecta evolution and the broad-band light curve. In our calculations, we find that a strong reverse shock efficiently decelerates and compresses the ejecta material. This leads to a significant broadening of the optical light curve, a longer rise to maximum and a slower decline in the tail phase. During the interaction, substantial radiative energy is generated, which mostly emerges in the extreme ultraviolet and X-ray regime. Only if reprocessing due to radiation-matter interactions is very efficient, a significant boost in the optical light curve is observed. We discuss these findings in particular in the context of the super-luminous event SN 2009dc. As our calculations are able...

  14. A Complete Survey of the Transient Radio Sky and Implications for Gamma-Ray Bursts, Supernovae, and other Relativistic Explosions

    CERN Document Server

    Gal-Yam, A; Poznanski, D; Levinson, A; Waxman, E; Frail, D A; Soderberg, A M; Nakar, E; Li, W; Filippenko, A V; Gal-Yam, Avishay; Ofek, Eran O.; Poznanski, Dovi; Levinson, Amir; Waxman, Eli; Frail, Dale A.; Soderberg, Alicia M.; Nakar, Ehud; Li, Weidong; Filippenko, Alexei V.

    2006-01-01

    We had previously reported on a survey for radio transients, used to set an upper limit on the number of orphan gamma-ray burst (GRB) radio afterglows, and thus a lower limit on the typical GRB beaming factor. Here we report radio and optical follow-up observations of these possible transients, achieving the first full characterization of the transient radio sky. We find that only two source are likely to be real radio transients, an optically obscured radio supernova (SN) in the nearby galaxy NGC 4216, and a source not associated with a bright host galaxy, which is too radio luminous to be a GRB afterglow. We speculate that this may be a flare from a peculiar active galactic nucleus, or a burst from an unusual Galactic compact object. We place an upper limit of 65 radio transients above 6 mJy over the entire sky at the 95% confidence level. The implications are as follows. First, we derive a limit on the typical beaming of GRBs; we find f_b^{-1} >~ 60, ~5 times higher than our earlier results. Second, we imp...

  15. Models for the evolution of close binaries with He-Star and WD components towards Type Ia supernova explosions

    CERN Document Server

    Neunteufel, P; Langer, N

    2016-01-01

    Type Ia supernovae (SNe Ia) have been an important tool for astronomy for quite some time; however, the nature of their progenitors remains somewhat mysterious. Recent theoretical studies indicated the possibility of producing thermonuclear detonations of carbon-oxygen white dwarfs (CO WDs) at masses less than the Chandrasekhar mass through accretion of helium-rich matter, which would, depending on mass accretion rate, mass, and initial temperature of the WD, spectrally resemble either a normal SN Ia or a peculiar one. This study aims to further resolve the state of binary systems comprised of a sub-Chandrasekhar-mass CO WD and a helium star at the point where an accretion-induced detonation occurs and constrains the part of the initial parameter space where this kind of phenomenon is possible. Preexisting data obtained through simulations of single, constantly accreting CO WDs is used as an indicator for the behavior of new binary models in which the WD is treated as a point mass and which include the non-de...

  16. Using the X-ray Morphologies of Young Supernova Remnants to Constrain Explosion Type, Ejecta Distribution, and Chemical Mixing

    CERN Document Server

    Lopez, Laura A; Huppenkothen, Daniela; Badenes, Carles; Pooley, David

    2010-01-01

    Supernova remnants (SNRs) are a complex class of sources, and their heterogeneous nature has hindered the characterization of their general observational properties. To overcome this challenge, we use statistical tools to analyze the Chandra X-ray images of Galactic and Large Magellanic Cloud SNRs. We apply two techniques, a power-ratio method (a multipole expansion) and wavelet-transform analysis, to measure the global and local morphological properties of the X-ray line and thermal emission in twenty-four SNRs. We find that Type Ia SNRs have statistically more spherical and mirror symmetric thermal X-ray emission than core-collapse (CC) SNRs. The ability to type SNRs based on thermal emission morphology alone enables, for the first time, the typing of SNRs with weak X-ray lines or with low-resolution spectra. We identify one source, SNR G344.7-0.1, as originating from a CC explosion that was previously unknown, and we confirm the tentative Type Ia classifications of G337.2-0.7 and G272.2-3.2. Although the g...

  17. SN1987A's Twentieth Anniversary

    Science.gov (United States)

    2007-02-01

    Looking back at 20 Years of Observations of this Supernova with ESO telescopes The unique supernova SN 1987A has been a bonanza for astrophysicists. It provided several observational 'firsts,' like the detection of neutrinos from an exploding star, the observation of the progenitor star on archival photographic plates, the signatures of a non-spherical explosion, the direct observation of the radioactive elements produced during the blast, observation of the formation of dust in the supernova, as well as the detection of circumstellar and interstellar material. ESO PR Photo 08a/07 ESO PR Photo 08a/07 SN1987A in the Large Magellanic Cloud Today, it is exactly twenty years since the explosion of Supernova 1987A in the Large Magellanic Cloud was first observed, at a distance of 163,000 light-years. It was the first naked-eye supernova to be seen for 383 years. Few events in modern astronomy have met with such an enthusiastic response by the scientists and now, after 20 years, it continues to be an extremely exciting object that is further studied by astronomers around the world, in particular using ESO's telescopes. When the first signs of Supernova 1987A, the first supernova of the year 1987, were noticed early on 24 February of that year, it was clear that this would be an unusual event. It was discovered by naked-eye and on a panoramic photographic plate taken with a 10-inch astrograph on Las Campanas in Chile by Oscar Duhalde and Ian Shelton, respectively. A few hours earlier, still on 23 February, two large underground detectors - in Japan and the USA - had registered the passage of high-energy neutrinos. Since SN 1987A exploded in the Large Magellanic Cloud (LMC), it was only accessible to telescopes in the Southern Hemisphere, more particularly in Australia, South Africa, and South America. In Chile, ESO's observatory at La Silla with its armada of telescopes with sizes between 0.5 and 3.6-m, played an important role. ESO PR Photo 08c/07 ESO PR Photo 08c/07 The

  18. OISTER Optical and Near-Infrared Observations of the Super-Chandrasekhar Supernova Candidate SN 2012dn: Dust Emission from the Circumstellar Shell

    CERN Document Server

    Yamanaka, Masayuki; Tanaka, Masaomi; Tominaga, Nozomu; Kawabata, Koji S; Takaki, Katsutoshi; Kawabata, Miho; Nakaoka, Tatsuya; Ueno, Issei; Akitaya, Hiroshi; Nagayama, Takahiro; Takahashi, Jun; Honda, Satoshi; Omodaka, Toshihiro; Miyanoshita, Ryo; Nagao, Takashi; Watanabe, Makoto; Isogai, Mizuki; Arai, Akira; Itoh, Ryosuke; Ui, Takahiro; Uemura, Makoto; Yoshida, Michitoshi; Hanayama, Hidekazu; Kuroda, Daisuke; Ukita, Nobuharu; Yanagisawa, Kenshi; Izumiura, Hideyuki; Saito, Yoshihiko; Masumoto, Kazunari; Ono, Rikako; Noguchi, Ryo; Matsumoto, Katsura; Nogami, Daisaku; Morokuma, Tomoki; Oasa, Yumiko; Sekiguchi, Kazuhiro

    2016-01-01

    We present extensively dense observations of the super-Chandrasekhar supernova (SC SN) candidate SN 2012dn from $-11$ to $+140$ days after the date of its $B$-band maximum in the optical and near-infrared (NIR) wavelengths conducted through the OISTER ToO program. The NIR light curves and color evolutions up to 35 days after the $B$-band maximum provided an excellent match with those of another SC SN 2009dc, providing a further support to the nature of SN 2012dn as a SC SN. We found that SN 2012dn exhibited strong excesses in the NIR wavelengths from $30$ days after the $B$-band maximum. The $H$ and $K_{s}$-band light curves exhibited much later maximum dates at $40$ and $70$ days after the $B$-band maximum, respectively, compared with those of normal SNe Ia. The $H$ and $K_{s}$-band light curves subtracted by those of SN 2009dc displayed plateaued evolutions, indicating a NIR echo from the surrounding dust. The distance to the inner boundary of the dust shell is limited to be $4.8 - 6.4\\times10^{-2}$ pc. No ...

  19. The phase diagram of QCD, third families of proto-compact stars, and the possibility of core-collapse supernova explosions

    CERN Document Server

    Hempel, Matthias; Yudin, Andrey; Iosilevskiy, Igor; Liebendörfer, Matthias; Thielemann, Friedrich-Karl

    2015-01-01

    A phase transition (PT) to quark matter can lead to interesting phenomenological consequences in core-collapse supernovae, e.g., triggering an explosion in spherically symmetric models. However, until now this explosion mechanism was only shown to be working for equations of state that are in contradiction with recent pulsar mass measurements. Here we identify that this explosion mechanism is related to the existence of a third family of compact stars that is present only in the hot, early stages of their evolution. Its existence is a result of unusual thermal properties of the two-phase coexistence region of the PT, e.g., characterized by a decrease of temperature with increasing density for isentropes, and which can be related to a negative slope of the PT line in the temperature-pressure phase diagram.

  20. On the Progenitor System of the Type Iax Supernova 2014dt in M61

    CERN Document Server

    Foley, Ryan J; Jha, Saurabh W; Clubb, Kelsey I; Filippenko, Alexei V; Mauerhan, Jon C; Miller, Adam A; Smith, Nathan

    2014-01-01

    We present pre-explosion and post-explosion Hubble Space Telescope images of the Type Iax supernova (SN Iax) 2014dt in M61. After astrometrically aligning these images, we do not detect any stellar sources at the position of the SN in the pre-explosion images to relatively deep limits (3 sigma limits of M_F438W > -5.0 mag and M_F814W > -5.9 mag). These limits are similar to the luminosity of SN 2012Z's progenitor system (M_F435W = -5.43 +/- 0.15 and M_F814W = -5.24 +/- 0.16 mag), the only probable detected progenitor system in pre-explosion images of a SN Iax, and indeed, of any white dwarf supernova. SN 2014dt is consistent with having a C/O white-dwarf primary/helium-star companion progenitor system, as was suggested for SN 2012Z, although perhaps with a slightly smaller or hotter donor. The data are also consistent with SN 2014dt having a low-mass red giant or main-sequence star companion. The data rule out main-sequence stars with M_init > 16 M_sun and most evolved stars with M_init > 8 M_sun as being the...

  1. Sn1987a Revisited after 20 Years: May the Supernova Bang More Than Once?

    CERN Document Server

    Galeotti, P

    2007-01-01

    The observations of supernova 1987A in underground detectors are revisited. It is shown that, while the LSD detector in the Mont Blanc Laboratory observed only one burst at 2h 52min 36.8sec U.T., the Kamiokande data show a possible second burst, in addition to the well known one at 7h 35min 33.7sec U.T. This second burst consists of a cluster of seven pulses, well above the energy threshold of the detector, observed during 6.2 seconds starting at 7h 54min 22.2sec U.T. Do these observations imply a long duration of the collapse?

  2. Supernova Feedback and Multiphase Interstellar Medium

    Science.gov (United States)

    Li, Miao; Ostriker, Jeremiah P.; Cen, Renyue; Bryan, Greg; Naab, Thorsten

    2015-01-01

    Without feedback, galaxies in cosmological simulations fail to generate outflows and tend to be too massive and too centrally concentrated, in contrast to the prominent disks observed ubiquitously in our universe. The nature of supernova (SN) feedback remains, however, highly uncertain, and most galaxy simulations so far adopt ad hoc models. Here we perform parsec-resolution simulations of a patch of the interstellar medium (ISM), and show that the unresolved multiphase gas in cosmological simulations can greatly affect the SN feedback by allowing blastwaves to travel in-between the clouds. We also show how ISM clumping varies with the mean gas density and SN rate encountered in real galactic environments. We emphasize that the inhomogeneity of the ISM must be considered in coarse-resolution simulations. We discuss how the gas pressure maintained by SN explosions can help to launch the galactic winds, and compare our results with the sub-grid models adopted in current cosmological simulations.

  3. ANALYTICAL LIGHT CURVE MODELS OF SUPERLUMINOUS SUPERNOVAE: {chi}{sup 2}-MINIMIZATION OF PARAMETER FITS

    Energy Technology Data Exchange (ETDEWEB)

    Chatzopoulos, E.; Wheeler, J. Craig; Vinko, J. [Department of Astronomy, University of Texas at Austin, Austin, TX (United States); Horvath, Z. L.; Nagy, A., E-mail: manolis@astro.as.utexas.edu [Department of Optics and Quantum Electronics, University of Szeged (Hungary)

    2013-08-10

    We present fits of generalized semi-analytic supernova (SN) light curve (LC) models for a variety of power inputs including {sup 56}Ni and {sup 56}Co radioactive decay, magnetar spin-down, and forward and reverse shock heating due to supernova ejecta-circumstellar matter (CSM) interaction. We apply our models to the observed LCs of the H-rich superluminous supernovae (SLSN-II) SN 2006gy, SN 2006tf, SN 2008am, SN 2008es, CSS100217, the H-poor SLSN-I SN 2005ap, SCP06F6, SN 2007bi, SN 2010gx, and SN 2010kd, as well as to the interacting SN 2008iy and PTF 09uj. Our goal is to determine the dominant mechanism that powers the LCs of these extraordinary events and the physical conditions involved in each case. We also present a comparison of our semi-analytical results with recent results from numerical radiation hydrodynamics calculations in the particular case of SN 2006gy in order to explore the strengths and weaknesses of our models. We find that CS shock heating produced by ejecta-CSM interaction provides a better fit to the LCs of most of the events we examine. We discuss the possibility that collision of supernova ejecta with hydrogen-deficient CSM accounts for some of the hydrogen-deficient SLSNe (SLSN-I) and may be a plausible explanation for the explosion mechanism of SN 2007bi, the pair-instability supernova candidate. We characterize and discuss issues of parameter degeneracy.

  4. The Candidate Progenitor of the Type IIn SN 2010jl is Not an Optically Luminous Star

    CERN Document Server

    Fox, Ori D; Dwek, Eli; Smith, Nathan; Filippenko, Alexei V; Andrews, Jennifer; Arendt, Richard G; Foley, Ryan J; Kelly, Patrick L; Miller, Adam A; Shivvers, Isaac

    2016-01-01

    The nature of the progenitor star (or system) for the Type IIn supernova (SN) subclass remains uncertain. While there are direct imaging constraints on the progenitors of at least four Type IIn supernovae, one of them being SN 2010jl, ambiguities remain in the interpretation of the unstable progenitors and the explosive events themselves. A blue source in pre-explosion HST/WFPC2 images falls within the 5 sigma astrometric error circle derived from post-explosion ground-based imaging of SN 2010jl. At the time the ground-based astrometry was published, however, the SN had not faded sufficiently for post-explosion HST follow-up observations to determine a more precise astrometric solution and/or confirm if the pre-explosion source had disappeared, both of which are necessary to ultimately disentangle the possible progenitor scenarios. Here we present HST/WFC3 imaging of the SN 2010jl field obtained in 2014 and 2015, when the SN had faded sufficiently to allow for new constraints on the progenitor. The SN, which ...

  5. Peculiar Type II Supernovae from Blue Supergiants

    CERN Document Server

    Kleiser, Io K W; Kasen, Daniel; Young, Timothy R; Chornock, Ryan; Filippenko, Alexei V; Challis, Peter; Ganeshalingam, Mohan; Kirshner, Robert P; Li, Weidong; Matheson, Thomas; Nugent, Peter E; Silverman, Jeffrey M

    2011-01-01

    The vast majority of Type II supernovae (SNe) are produced by red supergiants (RSGs), but SN 1987A revealed that blue supergiants (BSGs) can produce members of this class as well, albeit with some peculiar properties. This best studied event revolutionized our understanding of SNe, and linking it to the bulk of Type II events is essential. We present here optical photometry and spectroscopy gathered for SN 2000cb, which is clearly not a standard Type II SN and yet is not a SN 1987A analog. The light curve of SN 2000cb is reminiscent of that of SN 1987A in shape, with a slow rise to a late optical peak, but on substantially different time scales. Spectroscopically, SN 2000cb resembles a normal SN II but with ejecta velocities that far exceed those measured for SN 1987A or normal SNe II, above 18000 km/s for H-alpha at early times. The red colours, high velocities, late photometric peak, and our modeling of this object all point toward a scenario involving the high-energy explosion of a small-radius star, most ...

  6. PSR B 1706-44 and the SNR G 343.1-2.3 as the remnants of a cavity supernova explosion

    CERN Document Server

    Bock, D C J

    2002-01-01

    The possible association of the supernova remnant (SNR) G 343.1-2.3 with the pulsar PSR B 1706-44 (superposed on the arclike "shell" of the SNR) has been questioned by some authors on the basis of an inconsistency between the implied and measured (scintillation) transverse velocities of the pulsar, the absence of any apparent interaction between the pulsar and the SNR's "shell", and some other indirect arguments. We suggest, however, that this association could be real if both objects are the remnants of a supernova (SN) which exploded within a mushroom-like cavity (created by the SN progenitor wind breaking out of the parent molecular cloud). This suggestion implies that the actual shape of the SNR's shell is similar to that of the well-known SNR VRO 42.05.01 and that the observed bright arc corresponds to the "half" of the SNR located inside the cloud. We report the discovery in archival radio data of an extended ragged radio arc to the southeast of the bright arc which we interpret as the "half" of the SN ...

  7. The spectacular evolution of Supernova 1996al over 15 years: a low energy explosion of a stripped massive star in a highly structured environment

    CERN Document Server

    Benetti, Stefano; Utrobin, Victor P; Cappellaro, Enrico; Patat, Ferdinando; Pastorello, Andrea; Turatto, Massimo; Cupani, Guido; Neuhauser, Ralph; Caldwell, Nelson; Pignata, Giuliano; Tomasella, Lina

    2015-01-01

    Spectrophotometry of SN 1996al carried out throughout 15 years is presented. The early photometry suggests that SN 1996al is a Linear type-II supernova, with an absolute peak of Mv ~ -18.2 mag. Early spectra present broad, asymmetric Balmer emissions, with super-imposed narrow lines with P-Cygni profile, and He I features with asymmetric, broad emission components. The analysis of the line profiles shows that the H and He broad components form in the same region of the ejecta. By day +142, the Halpha profile dramatically changes: the narrow P-Cygni profile disappears, and the Halpha is fitted by three emission components, that will be detected over the remaining 15 yrs of the SN monitoring campaign. Instead, the He I emissions become progressively narrower and symmetric. A sudden increase in flux of all He I lines is observed between 300 and 600 days. Models show that the supernova luminosity is sustained by the interaction of low mass (~1.15 Msun) ejecta, expelled in a low kinetic energy (~ 1.6 x 10^50 erg) ...

  8. Impacto ambiental de los remanentes de supernova

    Science.gov (United States)

    Dubner, G. M.

    2015-08-01

    The explosion of a supernovae (SN) represents the sudden injection of about 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.

  9. Final Evolution and Delayed Explosions of Spinning White Dwarfs in Single Degenerate Models for Type Ia Supernovae

    CERN Document Server

    Benvenuto, Omar G; Kitamura, Hikaru; Hachisu, Izumi

    2015-01-01

    We study the occurrence of delayed SNe~Ia in the single degenerate (SD) scenario. We assume that a massive carbon-oxygen (CO) white dwarf (WD) accretes matter coming from a companion star, making it to spin at the critical rate. We assume uniform rotation due to magnetic field coupling. The carbon ignition mass for non-rotating WDs is M_{ig}^{NR} \\approx 1.38 M_{\\odot}; while for the case of uniformly rotating WDs it is a few percent larger (M_{ig}^{R} \\approx 1.43 M_{\\odot}). When accretion rate decreases, the WD begins to lose angular momentum, shrinks, and spins up; however, it does not overflow its critical rotation rate, avoiding mass shedding. Thus, angular momentum losses can lead the CO WD interior to compression and carbon ignition, which would induce an SN~Ia. The delay, largely due to the angular momentum losses timescale, may be large enough to allow the companion star to evolve to a He WD, becoming undetectable at the moment of explosion. This scenario supports the occurrence of delayed SNe~Ia if...

  10. 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

  11. A runaway collision in a young star cluster as the origin of the brightest supernova.

    Science.gov (United States)

    Portegies Zwart, Simon F; van den Heuvel, Edward P J

    2007-11-15

    Supernova SN 2006gy in the galaxy NGC 1260 is the most luminous recorded. Its progenitor might have been a very massive (>100 Mo, where is the mass of the Sun) star, but that interpretation is incompatible with hydrogen in the spectrum of the supernova; stars >40 Moare believed to have shed their hydrogen envelopes several hundred thousand years before the explosion. Alternatively, the progenitor might have arisen from the merger of two massive stars. Here we show that the collision frequency of massive stars in a dense and young cluster (of the kind to be expected near the centre of a galaxy) is sufficient to provide a reasonable chance that SN 2006gy resulted from such a bombardment. If this is the correct explanation, then we predict that when the supernova fades (in a year or so) a dense cluster of massive stars will become visible at the site of the explosion.

  12. Neutrinos from Type Ia Supernovae: The Gravitationally Confined Detonation Scenario

    CERN Document Server

    Wright, Warren P; Ohlmann, Sebastian T; Roepke, Friedrich K; Scholberg, Kate; Seitenzahl, Ivo R

    2016-01-01

    Despite their use as cosmological distance indicators and their importance in the chemical evolution of Galaxies, the unequivocal identification of the progenitor systems and explosion mechanism of normal Type Ia supernova (SN Ia) remains elusive. The leading hypothesis is that such a supernova is a thermonuclear explosion of a carbon-oxygen white dwarf but the exact explosion mechanism is still a matter of debate. Observation of a Galactic SN Ia would be of immense value in answering the many open questions related to these events. One potentially useful source of information about the explosion mechanism and progenitor is the neutrino signal. In this paper we compute the expected neutrino signal from a Gravitationally Confined Detonation (GCD) explosion scenario for a SN~Ia and show how the flux at Earth contains features in time and energy unique to this scenario. We then calculate the expected event rates in the Super-K, Hyper-K, JUNO, DUNE, and IceCube detectors and find both Hyper-K and IceCube would se...

  13. SPECTROSCOPIC OBSERVATIONS OF SN 2012fr: A LUMINOUS, NORMAL TYPE Ia SUPERNOVA WITH EARLY HIGH-VELOCITY FEATURES AND A LATE VELOCITY PLATEAU

    Energy Technology Data Exchange (ETDEWEB)

    Childress, M. J.; Scalzo, R. A.; Sim, S. A.; Tucker, B. E.; Yuan, F.; Schmidt, B. P. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Cenko, S. B.; Filippenko, A. V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Silverman, J. M. [Department of Astronomy, University of Texas, Austin, TX 78712-0259 (United States); Contreras, C.; Hsiao, E. Y.; Phillips, M.; Morrell, N. [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Jha, S. W.; McCully, C. [Department of Physics and Astronomy, Rutgers, State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Anderson, J. P.; De Jaeger, T.; Forster, F. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Benetti, S. [INAF Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Bufano, F., E-mail: mjc@mso.anu.edu.au [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); and others

    2013-06-10

    We present 65 optical spectra of the Type Ia SN 2012fr, 33 of which were obtained before maximum light. At early times, SN 2012fr shows clear evidence of a high-velocity feature (HVF) in the Si II {lambda}6355 line that can be cleanly decoupled from the lower velocity ''photospheric'' component. This Si II {lambda}6355 HVF fades by phase -5; subsequently, the photospheric component exhibits a very narrow velocity width and remains at a nearly constant velocity of {approx}12,000 km s{sup -1} until at least five weeks after maximum brightness. The Ca II infrared triplet exhibits similar evidence for both a photospheric component at v Almost-Equal-To 12,000 km s{sup -1} with narrow line width and long velocity plateau, as well as an HVF beginning at v Almost-Equal-To 31,000 km s{sup -1} two weeks before maximum. SN 2012fr resides on the border between the ''shallow silicon'' and ''core-normal'' subclasses in the Branch et al. classification scheme, and on the border between normal and high-velocity Type Ia supernovae (SNe Ia) in the Wang et al. system. Though it is a clear member of the ''low velocity gradient'' group of SNe Ia and exhibits a very slow light-curve decline, it shows key dissimilarities with the overluminous SN 1991T or SN 1999aa subclasses of SNe Ia. SN 2012fr represents a well-observed SN Ia at the luminous end of the normal SN Ia distribution and a key transitional event between nominal spectroscopic subclasses of SNe Ia.

  14. [O I] λλ6300, 6364 IN THE NEBULAR SPECTRUM OF A SUBLUMINOUS TYPE Ia SUPERNOVA

    Energy Technology Data Exchange (ETDEWEB)

    Taubenberger, S.; Kromer, M.; Hillebrandt, W. [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Pakmor, R. [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Pignata, G. [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Maeda, K. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Hachinger, S. [Julius-Maximilians-Universität Würzburg, Emil-Fischer-Str. 31, D-97074 Würzburg (Germany); Leibundgut, B. [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany)

    2013-10-01

    In this Letter, a late-phase spectrum of SN 2010lp, a subluminous Type Ia supernova (SN Ia), is presented and analyzed. As in 1991bg-like SNe Ia at comparable epochs, the spectrum is characterized by relatively broad [Fe II] and [Ca II] emission lines. However, instead of narrow [Fe III] and [Co III] lines that dominate the emission from the innermost regions of 1991bg-like supernovae (SNe), SN 2010lp shows [O I] λλ6300, 6364 emission, usually associated with core-collapse SNe and never previously observed in a subluminous thermonuclear explosion. The [O I] feature has a complex profile with two strong, narrow emission peaks. This suggests that oxygen is distributed in a non-spherical region close to the center of the ejecta, severely challenging most thermonuclear explosion models discussed in the literature. We conclude that, given these constraints, violent mergers are presently the most promising scenario to explain SN 2010lp.

  15. On the Radio Polarization Signature of Efficient and Inefficient Particle Acceleration in Supernova Remnant SN 1006

    CERN Document Server

    Reynoso, Estela M; Moffett, David A

    2013-01-01

    We present a radio polarization study of SN 1006, based on combined VLA and ATCA observations at 20 cm that resulted in sensitive images with an angular resolution of 10 arcsec. The fractional polarization in the two bright radio and X-ray lobes of the SNR is measured to be 0.17, while in the southeastern sector, where the radio and non-thermal X-ray emission are much weaker, the polarization fraction reaches a value of 0.6 +- 0.2, close to the theoretical limit of 0.7. We interpret this result as evidence of a disordered, turbulent magnetic field in the lobes, where particle acceleration is believed to be efficient, and a highly ordered field in the southeast, where the acceleration efficiency has been shown to be very low. Utilizing the frequency coverage of our observations, an average rotation measure of ~12 rad/m2 is determined from the combined data set, which is then used to obtain the intrinsic direction of the magnetic field vectors. While the orientation of magnetic field vectors across the SNR shel...

  16. Separating Thermal and Nonthermal X-Rays in Supernova Remnants. I. Total Fits to SN 1006 AD

    Science.gov (United States)

    Dyer, K. K.; Reynolds, S. P.; Borkowski, K. J.; Allen, G. E.; Petre, R.

    2001-04-01

    The remnant of SN 1006 has an X-ray spectrum dominated by nonthermal emission, and pre-ASCA observations were well described by a synchrotron calculation with electron energies limited by escape. We describe the results of a much more stringent test: fitting spatially integrated ASCA GIS (0.6-8 keV) and RXTE PCA (3-10 keV) data with a combination of the synchrotron model SRESC newly ported to XSPEC and a new thermal shock model VPSHOCK. The new model can describe the continuum emission above 2 keV well, in both spatial distribution and spectrum. We find that the emission is dominantly nonthermal, with a small but noticeable thermal component: Mg and Si are clearly visible in the integrated spectrum. The synchrotron component rolls off smoothly from the extrapolated radio spectrum, with a characteristic rolloff frequency of 3.1×1017 Hz, at which the spectrum has dropped about a factor of 6 below a power-law extrapolation from the radio spectrum. Comparison of TeV observations with new TeV model images and spectra based on the X-ray model fits gives a mean postshock magnetic field strength of about 9 μG, implying (for a compression ratio of 4) an upstream magnetic field of 3 μG, and fixing the current energy content in relativistic electrons at about 7×1048 ergs, resulting in a current electron-acceleration efficiency of about 5%. This total energy is about 100 times the energy in the magnetic field. The X-ray fit also implies that electrons escape ahead of the shock above an energy of about 30 TeV. This escape could result from an absence of scattering magnetohydrodynamic waves above a wavelength of about 1017 cm. Our results indicate that joint thermal and nonthermal fitting, using sophisticated models, will be required for analysis of most supernova-remnant X-ray data in the future.

  17. Phase Transition of Newborn Neutron Stars as a Link of Supernova/Gamma-Ray Burst Connection

    CERN Document Server

    Wang, X Y; Lu, T; Wei, D M; Huang, Y F

    1999-01-01

    We here present a natural explanation of the puzzling connection between supernova and gamma-ray burst. An asymmetric supernova explosion produces a mildly relativistic jet and leaves a preferred baryon-free funnel for the fireball formed few days later by the conversion of the newborn neutron star to a strange star, or/and from the differentially rotating strange star. The fireball can be accelerated to ultra-relativistic velocity ($\\Gamma_0>100$) due to the very low baryon contamination of the strange star and subsequently produce the $\\gamma$-ray burst. Most of the conversion energy will finally turn into the kinetic energy of the supernova ejecta, leading to a very luminous supernova similar to SN1998bw. We also show that the late rise in the radio light curve of GRB980425/SN1998bw can be attributed to the energy input from the resultant strange star.

  18. 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...

  19. The dark energy survey Y1 supernova search: Survey strategy compared to forecasts and the photometric type Is SN volumetric rate

    Science.gov (United States)

    Fischer, John Arthur

    For 70 years, the physics community operated under the assumption that the expansion of the Universe must be slowing due to gravitational attraction. Then, in 1998, two teams of scientists used Type Ia supernovae to discover that cosmic expansion was actually acceler- ating due to a mysterious "dark energy." As a result, Type Ia supernovae have become the most cosmologically important transient events in the last 20 years, with a large amount of effort going into their discovery as well as understanding their progenitor systems. One such probe for understanding Type Ia supernovae is to use rate measurements to de- termine the time delay between star formation and supernova explosion. For the last 30 years, the discovery of individual Type Ia supernova events has been accelerating. How- ever, those discoveries were happening in time-domain surveys that probed only a portion of the redshift range where expansion was impacted by dark energy. The Dark Energy Survey (DES) is the first project in the "next generation" of time-domain surveys that will discovery thousands of Type Ia supernovae out to a redshift of 1.2 (where dark energy be- comes subdominant) and DES will have better systematic uncertainties over that redshift range than any survey to date. In order to gauge the discovery effectiveness of this survey, we will use the first season's 469 photometrically typed supernovee and compare it with simulations in order to update the full survey Type Ia projections from 3500 to 2250. We will then use 165 of the 469 supernovae out to a redshift of 0.6 to measure the supernovae rate both as a function of comoving volume and of the star formation rate as it evolves with redshift. We find the most statistically significant prompt fraction of any survey to date (with a 3.9? prompt fraction detection). We will also reinforce the already existing tension in the measurement of the delayed fraction between high (z > 1.2) and low red- shift rate measurements, where we find no

  20. Probing Dark Energy via Neutrino and Supernova Observatories

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Lawrence; Hall, Lawrence J.; Murayama, Hitoshi; Papucci, Michele; Perez, Gilad

    2006-07-10

    A novel method for extracting cosmological evolution parameters is proposed, using a probe other than light: future observations of the diffuse anti-neutrino flux emitted from core-collapse supernovae (SNe), combined with the SN rate extracted from future SN surveys. The relic SN neutrino differential flux can be extracted by using future neutrino detectors such as Gadolinium-enriched, megaton, water detectors or 100-kiloton detectors of liquid Argon or liquid scintillator. The core-collapse SN rate can be reconstructed from direct observation of SN explosions using future precision observatories. Our method, by itself, cannot compete with the accuracy of the optical-based measurements but may serve as an important consistency check as well as a source of complementary information. The proposal does not require construction of a dedicated experiment, but rather relies on future experiments proposed for other purposes.

  1. The Origin of the Near-infrared Excess in SN Ia 2012dn: Circumstellar Dust around the Super-Chandrasekhar Supernova Candidate

    Science.gov (United States)

    Nagao, Takashi; Maeda, Keiichi; Yamanaka, Masayuki

    2017-02-01

    The nature of progenitors of the so-called super-Chandrasekhar candidate Type Ia supernovae (SC-SNe Ia) has been actively debated. Recently, Yamanaka et al. reported a near-infrared (NIR) excess for SN 2012dn and proposed that the excess originates from an echo by circumstellar (CS) dust. In this paper, we examine a detailed distribution of the CS dust around SN 2012dn and investigate implications of the CS dust echo scenario for general cases of SC-SNe Ia. We find that a disk/bipolar CS medium configuration reproduces the NIR excess fairly well, where the radial density distribution is given by a stationary mass loss. The inner radius of the CS dust is 0.04 pc. The mass-loss rate of the progenitor system is estimated to be 1.2× {10}-5 and 3.2× {10}-6 M⊙ yr‑1 for the disk and bipolar CS medium configurations, respectively, which adds further support for the single-degenerate scenario. Our models limit SN 2009dc, another SC-SN Ia, to have a dust mass less than 0.16 times that of SN 2012dn. While this may merely indicate some variation on the CS environment among SC-SNe Ia, this could raise another interesting possibility. There could be two classes among SC-SNe Ia: the brighter SC-SNe Ia in a clean environment (SN 2009dc) and the fainter SC-SNe Ia in a dusty environment (SN 2012dn).

  2. Supernova Progenitors, Their Variability, and the Type IIP Supernova ASASSN-16fq in M66

    CERN Document Server

    Kochanek, C S; Adams, S M; Sukhbold, T; Prieto, J L; Muller, T; Bock, G; Brown, J S; Dong, Subo; Holoien, T W -S; Khan, R; Shappee, B J; Stanek, K Z

    2016-01-01

    We identify a pre-explosion counterpart to the nearby Type IIP supernova ASASSN-16fq (SN 2016cok) in archival Hubble Space Telescope (HST) data. The source appears to be a blend of several stars that prevents obtaining accurate photometry. However, with reasonable assumptions about the stellar temperature and extinction, the progenitor almost certainly had an initial mass M<17Msun, and was most likely in the mass range 8-12Msun. Observations once ASASSN-16fq has faded will have no difficulty accurately determining the properties of the progenitor. In 8 years of Large Binocular Telescope (LBT) data, no significant progenitor variability is detected to RMS limits of roughly 0.03 mag. Of the six nearby SN with constraints on low level variability, SN 1987A, SN 1993J, SN 2008cn, SN 2011dh, SN 2013ej and ASASSN-16fq, only the slowly fading progenitor of SN 2011dh showed clear evidence of variability. Excluding SN 1987A, the 90% confidence limit implied by these sources on the number of outbursts over the last d...

  3. The Type IIb Supernova 2013df and Its Cool Supergiant Progenitor

    CERN Document Server

    Van Dyk, Schuyler D; Fox, Ori D; Cenko, S Bradley; Clubb, Kelsey I; Filippenko, Alexei V; Foley, Ryan J; Miller, Adam A; Smith, Nathan; Kelly, Patrick L; Lee, William H; Ben-Ami, Sagi; Gal-Yam, Avishay

    2013-01-01

    We have obtained early-time photometry and spectroscopy of Supernova (SN) 2013df in NGC 4414. The SN is clearly of Type IIb, with notable similarities to SN 1993J. From its luminosity at secondary maximum light, it appears that less $^{56}$Ni ($\\lesssim 0.06\\ M_{\\odot}$) was synthesized in the SN 2013df explosion than was the case for the SNe IIb 1993J, 2008ax, and 2011dh. Based on a comparison of the light curves, the SN 2013df progenitor must have been more extended in radius prior to explosion than the progenitor of SN 1993J. The total extinction for SN 2013df is estimated to be $A_V=0.30$ mag. The metallicity at the SN location is likely to be solar. We have conducted Hubble Space Telescope (HST) Target of Opportunity observations of the SN with the Wide Field Camera 3, and from a precise comparison of these new observations to archival HST observations of the host galaxy obtained 14 years prior to explosion, we have identified the progenitor of SN 2013df to be a yellow supergiant, somewhat hotter than a ...

  4. A Radio Survey of Type Ib and Ic Supernovae: Searching for Engine Driven Supernovae

    CERN Document Server

    Berger, E; Frail, D A; Soderberg, A M

    2003-01-01

    The association of gamma-ray bursts (GRBs) and core-collapse supernovae (SNe) of Type Ib and Ic was motivated by the detection of SN 1998bw in the error box of GRB 980425 and the now-secure identification of a SN 1998bw-like event in the cosmological GRB 030329. The bright radio emission from SN 1998bw indicated that it possessed some of the unique attributes expected of GRBs, namely a large reservoir of energy in (mildly) relativistic ejecta and variable energy input. The two popular scenarios for the origin of SN 1998bw are a typical cosmological burst observed off-axis or a member of a new distinct class of supernova explosions (gSNe). In the former, about 0.5% of local Type Ib/c SNe are expected to be similar to SN1998bw; for the latter no such constraint exists. Motivated thus, we began a systematic program of radio observations of most reported Type Ib/c SNe accessible to the Very Large Array. Of the 33 SNe observed from late 1999 to the end of 2002 at most one is as bright as SN 1998bw. From this we co...

  5. A Study of the Type II-P Supernova 2003gd in M74

    CERN Document Server

    Hendry, M A; Maund, J R; Pastorello, A; Zampieri, L; Benetti, S; Turatto, M; Cappellaro, E; Meikle, W P S; Kotak, R; Irwin, M J; Jonker, P G; Vermaas, L; Peletier, R F; Van Woerden, H; Exter, K M; Pollacco, D L; Leon, S; Verley, S; Benn, C R; Pignata, G

    2005-01-01

    We present photometric and spectroscopic data of the type II-P supernova 2003gd, which was discovered in M74 close to the end of its plateau phase. SN 2003gd is the first type II supernova to have a directly confirmed red supergiant progenitor. We compare SN 2003gd with SN 1999em, a similar type II-P supernova, and estimate an explosion date of 18th March 2003. We determine a reddening towards the supernova of E(B-V) = 0.14+/-0.06, using three different methods. We also calculate three new distances to M74 of 9.6+/-2.8 Mpc, 7.7+/-1.7 Mpc and 9.6+/-2.2 Mpc. The former was estimated using the Standardised Candle Method (SCM), for type II supernovae, and the latter two using the Brightest Supergiants Method (BSM). When combined with existing kinematic and BSM distance estimates, we derive a mean value of 9.3+/-1.8 Mpc. SN 2003gd was found to have a lower tail luminosity compared to other ``normal'' type II-P SNe bringing into question the nature of this supernova. We present a discussion concluding that this is ...

  6. A mildly relativistic radio jet from the otherwise normal type Ic supernova 2007gr.

    Science.gov (United States)

    Paragi, Z; Taylor, G B; Kouveliotou, C; Granot, J; Ramirez-Ruiz, E; Bietenholz, M; van der Horst, A J; Pidopryhora, Y; van Langevelde, H J; Garrett, M A; Szomoru, A; Argo, M K; Bourke, S; Paczyński, B

    2010-01-28

    The class of type Ic supernovae have drawn increasing attention since 1998 owing to their sparse association (only four so far) with long duration gamma-ray bursts (GRBs). Although both phenomena originate from the core collapse of a massive star, supernovae emit mostly at optical wavelengths, whereas GRBs emit mostly in soft gamma-rays or hard X-rays. Though the GRB central engine generates ultra-relativistic jets, which beam the early emission into a narrow cone, no relativistic outflows have hitherto been found in type Ib/c supernovae explosions, despite theoretical expectations and searches. Here we report radio (interferometric) observations that reveal a mildly relativistic expansion in a nearby type Ic supernova, SN 2007gr. Using two observational epochs 60 days apart, we detect expansion of the source and establish a conservative lower limit for the average apparent expansion velocity of 0.6c. Independently, a second mildly relativistic supernova has been reported. Contrary to the radio data, optical observations of SN 2007gr indicate a typical type Ic supernova with ejecta velocities approximately 6,000 km s(-1), much lower than in GRB-associated supernovae. We conclude that in SN 2007gr a small fraction of the ejecta produced a low-energy mildly relativistic bipolar radio jet, while the bulk of the ejecta were slower and, as shown by optical spectropolarimetry, mildly aspherical.

  7. Spatial Variations of the Synchrotron Spectrum Within Tycho’s Supernova Remnant (3C 10): A Spectral Tomography Analysis of Radio Observations at 20 and 90 Centimeter Wavelengths

    Science.gov (United States)

    2000-01-20

    individual ( Tycho ) 1. INTRODUCTION A new star observed by Tycho Brahe (1573) is now identi- Ðed as a supernova whose remnant (SNR) is 3C 10 (SN 1572... Tycho SNR, SNR 120.1]1.4 ; Lozinskaya 1992 and references therein). The explosion itself was mostly likely a Type Ia supernova, and the remnant seems...we adopted.3 Again, this procedure tends to reduce any spectral variations. However, as Reynoso et al. (1997) found, Tycho is not expanding

  8. The Quiet Explosion

    Science.gov (United States)

    2008-07-01

    A European-led team of astronomers are providing hints that a recent supernova may not be as normal as initially thought. Instead, the star that exploded is now understood to have collapsed into a black hole, producing a weak jet, typical of much more violent events, the so-called gamma-ray bursts. The object, SN 2008D, is thus probably among the weakest explosions that produce very fast moving jets. This discovery represents a crucial milestone in the understanding of the most violent phenomena observed in the Universe. Black Hole ESO PR Photo 23a/08 A Galaxy and two Supernovae These striking results, partly based on observations with ESO's Very Large Telescope, will appear tomorrow in Science Express, the online version of Science. Stars that were at birth more massive than about 8 times the mass of our Sun end their relatively short life in a cosmic, cataclysmic firework lighting up the Universe. The outcome is the formation of the densest objects that exist, neutron stars and black holes. When exploding, some of the most massive stars emit a short cry of agony, in the form of a burst of very energetic light, X- or gamma-rays. In the early afternoon (in Europe) of 9 January 2008, the NASA/STFC/ASI Swift telescope discovered serendipitously a 5-minute long burst of X-rays coming from within the spiral galaxy NGC 2770, located 90 million light-years away towards the Lynx constellation. The Swift satellite was studying a supernova that had exploded the previous year in the same galaxy, but the burst of X-rays came from another location, and was soon shown to arise from a different supernova, named SN 2008D. Researchers at the Italian National Institute for Astrophysics (INAF), the Max-Planck Institute for Astrophysics (MPA), ESO, and at various other institutions have observed the supernova at great length. The team is led by Paolo Mazzali of INAF's Padova Observatory and MPA. "What made this event very interesting," says Mazzali, "is that the X-ray signal was very

  9. NASA Scientists Witness a Supernova Cosmic Rite of Passage

    Science.gov (United States)

    2005-11-01

    Scientists using NASA's Chandra X-ray Observatory have witnessed a cosmic rite of passage, the transition from a supernova to a supernova remnant, a process that has never been seen in much detail until now, leaving it poorly defined. A supernova is a massive star explosion; the remnant is the beautiful glowing shell that evolves afterwards. When does a supernova become supernova remnant? When does the shell appear and what powers its radiant glow? A science team led by Dr. Stefan Immler of NASA's Goddard Space Flight Center, Greenbelt, Md., has taken a fresh look at a supernova that exploded in 1970, called SN 1970G, just off the handle of the Big Dipper. This is the oldest supernova ever seen by X-ray telescopes. Chandra X-ray Image of SN 1970G Chandra X-ray Image of SN 1970G "Some astronomers have thought there's a moment when the supernova remnant magically turns on years after the supernova itself has faded away, when the shock wave of the explosion finally hits and lights up the interstellar medium," said Immler. "By contrast, our results show that a new supernova quickly and seamlessly evolves into a supernova remnant. The star's own debris, and not the interstellar medium gas, fuels the remnant." These results appear in The Astrophysical Journal, co-authored by Dr. Kip Kuntz, also of Goddard. They support previous Chandra observations of SN 1987A by Dr. Sangwook Park of Penn State. Using new data from Chandra and archived data from the European-led ROSAT and XMM-Newton observatories, Immler and Kuntz pieced together how SN 1970G evolved over the years. They found telltale signs of a supernova remnant - bright X-ray light - yet no evidence of interstellar gas, even across a distance around the site of the explosion 35 times larger than our solar system. Instead, the material that is heated by the supernova shock to glow in X-ray light, what we call the remnant, is from the stellar wind of the star itself and not distant gas in the interstellar medium. This

  10. Modeling post-explosion anisotropies of ejecta in SNR Cassiopeia A

    Science.gov (United States)

    Orlando, S.; Miceli, M.; Pumo, M.; Bocchino, F.

    2016-06-01

    Supernova remnats (SNRs) show a complex morphology characterized by an inhomogeneous spatial distribution of ejecta, believed to reflect pristine structures and features of the progenitor supernova (SN) explosion. Filling the gap between SN explosions and their remnants is very important for a comprehension of the origin of present-day structure of ejecta in SNRs and to probe and constraint current models of SN explosions. The SNR Cassiopeia A (Cas A) is an attractive laboratory for studying the SNe-SNRs connection, being one of the best studied SNRs for which its 3D structure is known. We present a three-dimensional hydrodynamic model describing the evolution of Cas A from the immediate aftermath of the SN explosion to its expansion through the interstellar medium, taking into account the distribution of element abundances of the ejecta, the back reaction of accelerated cosmic rays at the shock front, and the deviations from equilibrium of ionizazion for the most important elements. We use the model to derive the physical parameters characterizing the SN explosion and reproducing the today morphology of Cas A.

  11. Experimental Testbed for the Study of Hydrodynamic Issues in Supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Robey, H F; Kane, J O; Remington, B A; Drake, R P; Hurricane, O A; Louis, H; Wallace, R J; Knauer, J; Keiter, P; Arnett, D

    2000-10-09

    More than a decade after the explosion of SN 1987A, unresolved discrepancies still remain in attempts to numerically simulate the mixing processes initiated by the passage of a very strong shock through the layered structure of the progenitor star. Numerically computed velocities of the radioactive {sup 56}Ni and {sup 56}CO, produced by shock-induced explosive burning within the silicon layer for example, are still more than 50% too low as compared with the measured velocities. In order to resolve such discrepancies between observation and simulation, an experimental testbed has been designed on the Omega Laser for the study of hydrodynamic issues of importance to supernovae (SNe). In this paper, we present results from a series of scaled laboratory experiments designed to isolate and explore several issues in the hydrodynamics of SN explosions. The results of the experiments are compared with numerical simulations and are generally found to be in reasonable agreement.

  12. Erratum to Star formation triggered by SN explosions: an application to the stellar association of $\\beta$Pictoris

    CERN Document Server

    Melioli, C; Leão, M R M; De la Reza, R; Raga, A

    2007-01-01

    In the present study, considering the physical conditions that are relevant interactions between supernova remnants (SNRs) and dense molecular clouds for triggering star formation we have built a diagram of SNR radius versus cloud density in which the constraints above delineate a shaded zone where star formation is allowed. We have also performed fully 3-D radiatively cooling numerical simulations of the impact between SNRs and clouds under different initial conditions in order to follow the initial steps of these interactions. We determine the conditions that may lead either to cloud collapse and star formation or to complete cloud destruction and find that the numerical results are consistent with those of the SNR-cloud density diagram. Finally, we have applied the results above to the $\\beta-$ Pictoris stellar association which is composed of low mass Post-T Tauri stars with an age of 11 Myr. It has been recently suggested that its formation could have been triggered by the shock wave produced by a SN exp...

  13. Supernova interaction with dense mass loss

    CERN Document Server

    Chevalier, Roger A

    2013-01-01

    Supernovae of Type IIn (narrow line) appear to be explosions that had strong mass loss before the event, so that the optical luminosity is powered by the circumstellar interaction. If the mass loss region has an optical depth $>c/v_s$, where $v_s$ is the shock velocity, the shock breakout occurs in the mass loss region and a significant fraction of the explosion energy can be radiated. The emission from the superluminous SN 2006gy and the normal luminosity SN 2011ht can plausibly be attributed to shock breakout in a wind, with SN 2011ht being a low energy event. Superluminous supernovae of Type I may derive their luminosity from interaction with a mass loss region of limited extent. However, the distinctive temperature increase to maximum luminosity has not been clearly observed in Type I events. Suggested mechanisms for the strong mass loss include pulsational pair instability, gravity-waves generated by instabilities in late burning phases, and binary effects.

  14. The Binary Progenitor of Tycho Brahe's Supernova

    Science.gov (United States)

    Ruiz-Lapuente, P.

    2006-08-01

    The brightness of type Ia supernovae, and their homogeneity as a class, makes them powerful tools in cosmology, yet little is known about the progenitor systems of these explosions. They are thought to arise when a white dwarf accretes matter from a companion star, is compressed and undergoes a thermonuclear explosion. Unless the companion star is another white dwarf (in which case it should be destroyed by the mass-transfer process itself), it should survive and show distinguishing properties. Tycho's supernova (SN 1572) provides an opportunity to address observationally the identification of the surviving companion. Here we report a survey of the central region of its remnant, around the position of the explosion, which excludes red giants as the mass donor of the exploding white dwarf. We found a type G0-G2 star, similar to our Sun in surface temperature and luminosity (but lower surface gravity), moving at more than three times the mean velocity of the stars at that distance, which appears to be the surviving companion of the supernova.

  15. Type-Ia Supernova Rates to Redshift 2.4 from Clash: The Cluster Lensing and Supernova Survey with Hubble

    Science.gov (United States)

    Graur, O.; Rodney, S. A.; Maoz, D.; Riess, A. G.; Jha, S. W.; Postman, M.; Dahlen, T.; Holoien, T. W.-S.; McCully, C.; Patel, B.; hide

    2014-01-01

    We present the supernova (SN) sample and Type-Ia SN (SN Ia) rates from the Cluster Lensing And Supernova survey with Hubble (CLASH). Using the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope (HST), we have imaged 25 galaxy-cluster fields and parallel fields of non-cluster galaxies. We report a sample of 27 SNe discovered in the parallel fields. Of these SNe, approximately 13 are classified as SN Ia candidates, including four SN Ia candidates at redshifts z greater than 1.2.We measure volumetric SN Ia rates to redshift 1.8 and add the first upper limit on the SN Ia rate in the range z greater than 1.8 and less than 2.4. The results are consistent with the rates measured by the HST/ GOODS and Subaru Deep Field SN surveys.We model these results together with previous measurements at z less than 1 from the literature. The best-fitting SN Ia delay-time distribution (DTD; the distribution of times that elapse between a short burst of star formation and subsequent SN Ia explosions) is a power law with an index of 1.00 (+0.06(0.09))/(-0.06(0.10)) (statistical) (+0.12/-0.08) (systematic), where the statistical uncertainty is a result of the 68% and 95% (in parentheses) statistical uncertainties reported for the various SN Ia rates (from this work and from the literature), and the systematic uncertainty reflects the range of possible cosmic star-formation histories. We also test DTD models produced by an assortment of published binary population synthesis (BPS) simulations. The shapes of all BPS double-degenerate DTDs are consistent with the volumetric SN Ia measurements, when the DTD models are scaled up by factors of 3-9. In contrast, all BPS single-degenerate DTDs are ruled out by the measurements at greater than 99% significance level.

  16. THE FIRST MAXIMUM-LIGHT ULTRAVIOLET THROUGH NEAR-INFRARED SPECTRUM OF A TYPE Ia SUPERNOVA

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Ryan J.; Marion, G. Howie; Challis, Peter; Kirshner, Robert P.; Berta, Zachory K. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Kromer, Markus; Taubenberger, Stefan; Hillebrandt, Wolfgang; Roepke, Friedrich K.; Ciaraldi-Schoolmann, Franco; Seitenzahl, Ivo R. [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Strasse 1, D-85748 Garching bei Muenchen (Germany); Pignata, Giuliano [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Stritzinger, Maximilian D. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, DK-8000 Aarhus C (Denmark); Filippenko, Alexei V.; Li Weidong; Silverman, Jeffrey M. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Folatelli, Gaston [Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa 277-8583 (Japan); Hsiao, Eric Y.; Morrell, Nidia I. [Carnegie Observatories, Las Campanas Observatory, La Serena (Chile); Simcoe, Robert A., E-mail: rfoley@cfa.harvard.edu [MIT-Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue, 37-664D Cambridge, MA 02139 (United States); and others

    2012-07-01

    We present the first maximum-light ultraviolet (UV) through near-infrared (NIR) Type Ia supernova (SN Ia) spectrum. This spectrum of SN 2011iv was obtained nearly simultaneously by the Hubble Space Telescope at UV/optical wavelengths and the Magellan Baade telescope at NIR wavelengths. These data provide the opportunity to examine t