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Sample records for energetic supernova sn

  1. SN 1006 and other historical supernovae

    Science.gov (United States)

    Stephenson, F. Richard

    2007-08-01

    The supernova which appeared in AD 1006 is unique in history for its brilliance, duration of visibility, and the interest it aroused. Almost thirty separate records of the star are preserved from various parts of the world. This paper briefly summarizes historical records of SN 1006 and discusses the prospects of uncovering further historical records of supernovae.

  2. The ASAS-SN bright supernova catalogue - III. 2016

    DEFF Research Database (Denmark)

    Holoien, T. W. -S.; Brown, J. S.; Stanek, K. Z.

    2017-01-01

    This catalogue summarizes information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) and all other bright (m(peak)d......This catalogue summarizes information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) and all other bright (m(peak)d...

  3. 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...

  4. Quark nova imprint in the extreme supernova explosion SN 2006gy

    Science.gov (United States)

    Ouyed, R.; Kostka, M.; Koning, N.; Leahy, D. A.; Steffen, W.

    2012-06-01

    The extremely luminous supernova 2006gy (SN 2006gy) is among the most energetic ever observed. The peak brightness was 100 times that of a typical supernova and it spent an unheard of 250 d at magnitude -19 or brighter. Efforts to describe SN 2006gy have pushed the boundaries of current supernova theory. In this work we aspire to simultaneously reproduce the photometric and spectroscopic observations of SN 2006gy using a quark nova (QN) model. This analysis considers the supernova explosion of a massive star followed days later by the QN detonation of a neutron star. We lay out a detailed model of the interaction between the supernova envelope and the QN ejecta paying special attention to a mixing region which forms at the inner edge of the supernova envelope. This model is then fitted to photometric and spectroscopic observations of SN 2006gy. This QN model naturally describes several features of SN 2006gy including the late-stage light-curve plateau, the broad Hα line and the peculiar blue Hα absorption. We find that a progenitor mass between 20 and 40 M⊙ provides ample energy to power SN 2006gy in the context of a QN.

  5. The ASAS-SN bright supernova catalogue - III. 2016

    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.; Bose, S.; Beacom, J. F.; Bersier, D.; Chen, Ping; Chomiuk, L.; Falco, E.; Godoy-Rivera, D.; Morrell, N.; Pojmanski, G.; Shields, J. V.; Strader, J.; Stritzinger, M. D.; Thompson, Todd A.; Woźniak, P. R.; Bock, G.; Cacella, P.; Conseil, E.; Cruz, I.; Fernandez, J. M.; Kiyota, S.; Koff, R. A.; Krannich, G.; Marples, P.; Masi, G.; Monard, L. A. G.; Nicholls, B.; Nicolas, J.; Post, R. S.; Stone, G.; Wiethoff, W. S.

    2017-11-01

    This catalogue summarizes information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) and all other bright (mpeak ≤ 17), spectroscopically confirmed supernovae discovered in 2016. We then gather the near-infrared through ultraviolet magnitudes of all host galaxies and the offsets of the supernovae from the centres of their hosts from public data bases. We illustrate the results using a sample that now totals 668 supernovae discovered since 2014 May 1, including the supernovae from our previous catalogues, with type distributions closely matching those of the ideal magnitude limited sample from Li et al. This is the third of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team.

  6. 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.

  7. A neutron-star-driven X-ray flash associated with supernova SN 2006aj.

    Science.gov (United States)

    Mazzali, Paolo A; Deng, Jinsong; Nomoto, Ken'ichi; Sauer, Daniel N; Pian, Elena; Tominaga, Nozomu; Tanaka, Masaomi; Maeda, Keiichi; Filippenko, Alexei V

    2006-08-31

    Supernovae connected with long-duration gamma-ray bursts (GRBs) are hyper-energetic explosions resulting from the collapse of very massive stars ( approximately 40 M\\circ, where M\\circ is the mass of the Sun) stripped of their outer hydrogen and helium envelopes. A very massive progenitor, collapsing to a black hole, was thought to be a requirement for the launch of a GRB. Here we report the results of modelling the spectra and light curve of SN 2006aj (ref. 9), which demonstrate that the supernova had a much smaller explosion energy and ejected much less mass than the other GRB-supernovae, suggesting that it was produced by a star whose initial mass was only approximately 20 M\\circ. A star of this mass is expected to form a neutron star rather than a black hole when its core collapses. The smaller explosion energy of SN 2006aj is matched by the weakness and softness of GRB 060218 (an X-ray flash), and the weakness of the radio flux of the supernova. Our results indicate that the supernova-GRB connection extends to a much broader range of stellar masses than previously thought, possibly involving different physical mechanisms: a 'collapsar' (ref. 8) for the more massive stars collapsing to a black hole, and magnetic activity of the nascent neutron star for the less massive stars.

  8. Supernova SN 2008iz in M82 Galaxy

    African Journals Online (AJOL)

    kagoyire

    Abstract. We report on multi-frequency Very Large Array (VLA) radio observations for an on-going monitoring campaign of supernova SN 2008iz in the nearby galaxy M82. We fit two light curve models to the data, a simple power-law model and a simplified Weiler model, yielding a decline index, β = -1.23±0.01 and ...

  9. Magnetic field in supernova remnant SN 1987A

    OpenAIRE

    Berezhko, E. G.; Ksenofontov, L. T.

    2006-01-01

    A nonlinear kinetic theory of cosmic ray (CR) acceleration in supernova remnants is employed to investigate the properties of the remnant SN 1987A. It is shown that a large downstream magnetic field ~10 mG is required to fit the existing observational data. Such a strong field together with the strong shock modification due to CR backreaction provides the steep and concave radioemission spectrum and considerable synchrotron cooling of high energy electrons which diminish their X-ray synchrotr...

  10. Neutral Hydrogen Radio Propperties of ASAS-SN Supernovae Hosts

    Science.gov (United States)

    Ross, Timothy W.; Salter, Chris; Ghosh, Tapasi; Minchin, Robert; Jones, Kristen; All-Sky Automated Survey for Supernovae (ASAS-SN)

    2018-01-01

    We compiled properties of the galaxies containing recent supernovae. The galaxies were observed in the Hydrogen 21-cm region using the Arecibo 305-m Radio Telescope, and the supernovae were found by the All-Sky Automated Survey for Supernovae (ASAS-SN) project. We were able to detect the neutral hydrogen hyperfine transition in 50 new galaxies to date, and retrieved information on 52 host galaxies with previous detections. Including archival detections, the detection rates of Type CC SNe was 96.9%, that of Type Ia was 76.3%, while no Tidal Disruption Events (TDEs) had detections. In all we calculated the integrated HI flux of 102 host galaxies in the Arecibo sky. With the integrated HI flux we calculated mass values. The median HI mass, log [MHI/(h‑2C M⊙)], with h =.73, for all SN host galaxies was 9.47±0.02, with the median for Type Ia hosts being 9.55±0.02 and the median for Type CC being 9.30±0.02.

  11. SN2002es-like Supernovae from Different Viewing Angles

    Science.gov (United States)

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

    2016-11-01

    In this article, we compare optical light curves of two SN2002es-like Type Ia supernovae (SNe), 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 r-band. On the one hand, iPTF14atg revealed a slow and steady rise that lasted for 22 days with a mean rise rate of 0.2-0.3 mag 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 \\gt 1.8 {{mag}} {{{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 from iPTF14dpk probably because of an unfavored viewing angle, provided that SN2002es-like events arise from the same progenitor channel. We further show that an SN2002es-like SN may experience a dark phase after the explosion but before its radioactively powered light curve becomes visible. This dark phase may be lit by radiation from supernova-companion interaction.

  12. The GRB 060218/SN 2006aj event in the context of other gamma-ray burst supernovae

    DEFF Research Database (Denmark)

    Ferrero, P.; Kann, D. A.; Zeh, A.

    2006-01-01

    Gamma rays: bursts: X-rays: individuals: GRB 060218, supernovae: individual: SN 2006aj Udgivelsesdato: Oct.......Gamma rays: bursts: X-rays: individuals: GRB 060218, supernovae: individual: SN 2006aj Udgivelsesdato: Oct....

  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. 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.

  15. GRB 161219B / SN 2016jca: A low-redshift gamma-ray burst supernova powered by radioactive heating

    DEFF Research Database (Denmark)

    Cano, Z.; Izzo, L.; De Ugarte Postigo, A.

    2017-01-01

    Since the first discovery of a broad-lined type Ic supernova (SN) with a long-duration gamma-ray burst (GRB) in 1998, fewer than fifty gamma-ray burst supernovae (GRB-SNe) have been discovered. The intermediate-luminosity Swift GRB 161219B and its associated supernova SN 2016jca, which occurred a...

  16. Supernova SN 1006 in two historic Yemeni reports

    Science.gov (United States)

    Rada, W.; Neuhäuser, R.

    2015-04-01

    We present two Arabic texts of historic observations of supernova SN 1006 from Yemen as reported by al-Yamāni and Ibn al-Daybac (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-Yamāni in its original Arabic and with our English translation. It is quite obvious that the report by Ibn al-Daybac is based on the report by al-Yamāni (or a common source), but the earlier report by al-Yamāni 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 April 17 ± 2 on the Julian calendar), as reported by both al-Yamāni and Ibn al-Daybac, i.e. {˜ 1.5} weeks earlier than the otherwise earliest known reports. We also briefly discuss other information from the Yemeni reports on brightness, light curve, duration of visibility, location, stationarity, and color.

  17. 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...

  18. 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.

  19. Supernova SN 2008iz in M82 galaxy | Kimani | Rwanda Journal

    African Journals Online (AJOL)

    ... than the surrounding flux, respectively. The flux density enhancement from day 1700 does not show signs of decline from results obtained so far. The enhancement is attributed to SN 2008iz expanding shock wave encounter with a clumpy dense circumstellar medium. Keywords: Supernova, SN 2008iz, Radio continuum, ...

  20. Electron cooling in a young radio supernova: SN 2012aw

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Naveen; Ray, Alak [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Chakraborti, Sayan [Institute for Theory and Computation, Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Stockdale, Christopher [Marquette University, Milwaukee, WI 53233 (United States); Chandra, Poonam [National Center for Radio Astronomy-TIFR, Pune 411007 (India); Smith, Randall [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Roy, Rupak; Bose, Subhash [Aryabhhata Research Institute of Observational Sciences, Nainital 263129 (India); Dwarkadas, Vikram [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Sutaria, Firoza [Indian Institute of Astrophysics, Bangalore 560034 (India); Pooley, David, E-mail: nyadav@tifr.res.in, E-mail: akr@tifr.res.in [Department of Physics, Sam Houston State University, Huntsville, TX 77341 (United States)

    2014-02-10

    We present the radio observations and modeling of an optically bright Type II-P supernova (SN), SN 2012aw which exploded in the nearby galaxy Messier 95 (M95) at a distance of 10 Mpc. The spectral index values calculated using C, X, and K bands are smaller than the expected values for the optically thin regime. During this time, the optical bolometric light curve stays in the plateau phase. We interpret the low spectral-index values to be a result of electron cooling. On the basis of comparison between the Compton cooling timescale and the synchrotron cooling timescale, we find that the inverse Compton cooling process dominates over the synchrotron cooling process. We therefore model the radio emission as synchrotron emission from a relativistic electron population with a high energy cutoff. The cutoff is determined by comparing the electron cooling timescale, t {sub cool}, and the acceleration timescale, t-tilde {sub acc}. We constrain the mass-loss rate in the wind ( M-dot ∼1.9×10{sup −6} M{sub ⊙} yr{sup −1}) and the equipartition factor between relativistic electrons and the magnetic field ( α-tilde =ϵ{sub e}/ϵ{sub B}∼1.12×10{sup 2}) through our modeling of radio emission. Although the time of explosion is fairly well constrained by optical observations within about two days, we explore the effect of varying the time of explosion to best fit the radio light curves. The best fit is obtained for the explosion date as 2012 March 15.3 UT.

  1. Du Pont Classifications of 8 ASAS-SN, ATLAS and Gaia Supernovae

    Science.gov (United States)

    Morrell, N.; Shappee, Benjamin J.; Drout, Maria

    2017-12-01

    We report optical spectroscopy (range 370-910 nm) of eight supernovae discovered by the All-Sky Automated Survey for Supernovae (ASAS-SN; Shappee et al. 2014, ApJ, 788, 48), ATLAS (Tonry et al. 2011, PASP, 123, 58) and Gaia using the du Pont 2.5-m telescope (+ WFCCD) at Las Campanas Observatory on Dec 17 through Dec 20 2016 UT. We performed a cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J.

  2. The Transition of a Type IIL Supernova into a Supernova Remnant: Late-time Observations of SN 2013by

    Science.gov (United States)

    Black, C. S.; Milisavljevic, D.; Margutti, R.; Fesen, R. A.; Patnaude, D.; Parker, S.

    2017-10-01

    We present early-time Swift and Chandra X-ray data along with late-time optical and near-infrared observations of SN 2013by, a Type IIL supernova (SN) that occurred in the nearby spiral galaxy ESO 138-G10 (D ˜ 14.8 Mpc). Optical and NIR photometry and spectroscopy follow the late-time evolution of the SN from days +89 to +457 post maximum brightness. The optical spectra and X-ray light curves are consistent with the picture of an SN having prolonged interaction with circumstellar material (CSM) that accelerates the transition from SN to supernova remnant (SNR). Specifically, we find SN 2013by’s Hα profile exhibits significant broadening (˜10,000 km s-1) on day +457, the likely consequence of high-velocity, H-rich material being excited by a reverse shock. A relatively flat X-ray light curve is observed that cannot be modeled using Inverse Compton scattering processes alone, but requires an additional energy source most likely originating from the SN-CSM interaction. In addition, we see the first overtone of CO emission near 2.3 μm on day +152, signaling the formation of molecules and dust in the SN ejecta and is the first time CO has been detected in a Type IIL SN. We compare SN 2013by with Type IIP SNe, whose spectra show the rarely observed SN-to-SNR transition in varying degrees and conclude that Type IIL SNe may enter the remnant phase at earlier epochs than their Type IIP counterparts.

  3. GAMMA RAYS FROM TYPE Ia SUPERNOVA SN 2014J

    Energy Technology Data Exchange (ETDEWEB)

    Churazov, E.; Sunyaev, R.; Grebenev, S. [Space Research Institute (IKI), Profsouznaya 84/32, Moscow 117997 (Russian Federation); Isern, J. [Institut for Space Sciences (ICE-CSIC/IEEC), E-08193 Bellaterra (Spain); Bikmaev, I. [Kazan Federal University (KFU), Kremlevskaya Strasse, 18, Kazan (Russian Federation); Bravo, E. [E.T.S.A.V., Univ. Politecnica de Catalunya, Carrer Pere Serra 1-15, E-08173 Sant Cugat del Valles (Spain); Chugai, N. [Institute of Astronomy of the Russian Academy of Sciences, 48 Pyatnitskaya Street, 119017, Moscow (Russian Federation); Jean, P.; Knödlseder, J. [Université de Toulouse, UPS-OMP, IRAP, Toulouse (France); Lebrun, F. [APC, Univ Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs de Paris, Sorbonne Paris Cité (France); Kuulkers, E. [European Space Astronomy Centre (ESA/ESAC), Science Operations Department, P.O. Box 78, E-28691 Villanueva de la Cañada, Madrid (Spain)

    2015-10-10

    The whole set of INTEGRAL observations of Type Ia supernova SN 2014J, covering the period 19–162 days after the explosion, has been analyzed. For spectral fitting the data are split into early and late periods covering days 19–35 and 50–162, respectively, optimized for {sup 56}Ni and {sup 56}Co lines. As expected for the early period, much of the gamma-ray signal is confined to energies below ∼200 keV, while for the late period it is strongest above 400 keV. In particular, in the late period, {sup 56}Co lines at 847 and 1248 keV are detected at 4.7σ and 4.3σ, respectively. The light curves in several representative energy bands are calculated for the entire period. The resulting spectra and light curves are compared with a subset of models. We confirm our previous finding that the gamma-ray data are broadly consistent with the expectations for canonical one-dimensional models, such as delayed detonation or deflagration models for a near-Chandrasekhar mass white dwarf. Late optical spectra (day 136 after the explosion) show rather symmetric Co and Fe line profiles, suggesting that, unless the viewing angle is special, the distribution of radioactive elements is symmetric in the ejecta.

  4. Suzaku Results of SN 1006: Chemical Abundances of the ``youngest'' Galactic Type Ia Supernova Remnant

    Science.gov (United States)

    Koyama, Katsuji

    2008-05-01

    SN 1006 is one of the supernova remnants (SNR) recorded in the Japanese diary ``Meigetsuki''. From the historical records including Meigetsuki, we conclude that SN 1006 was the brightest type Ia supernova remnant. We report on the observations of SN 1006 with the X-ray Imaging Spectrometers (XIS) on board the 5-th Japanese X-ray satellite Suzaku. We found that the ionization age of SN 1006 is the youngest among any Galactic SNRs, hence is the best SNR to study early phase of type Ia. In the X-ray spectrum, we found the K-shell emission lines from heavy elements, in particular that from iron, for the first time. The X-ray emitting plasma is highly overabundant in heavy elements, hence are likely due to ejecta. The abundance pattern agrees well to the theoretical prediction of type Ia supernova.

  5. Directed Searches for Broadband Extended Gravitational Wave Emission in Nearby Energetic Core-collapse Supernovae

    Science.gov (United States)

    van Putten, Maurice H. P. M.

    2016-03-01

    Core-collapse supernovae (CC-SNe) are factories of neutron stars and stellar-mass black holes. SNe Ib/c stand out as potentially originating in relatively compact stellar binaries and they have a branching ratio of about 1% into long gamma-ray bursts. The most energetic events probably derive from central engines harboring rapidly rotating black holes, wherein the accretion of fall-back matter down to the innermost stable circular orbit (ISCO) offers a window into broadband extended gravitational wave emission (BEGE). To search for BEGE, we introduce a butterfly filter in time-frequency space by time-sliced matched filtering. To analyze long epochs of data, we propose using coarse-grained searches followed by high-resolution searches on events of interest. We illustrate our proposed coarse-grained search on two weeks of LIGO S6 data prior to SN 2010br (z = 0.002339) using a bank of up to 64,000 templates of one-second duration covering a broad range in chirp frequencies and bandwidth. Correlating events with signal-to-noise ratios > 6 from the LIGO L1 and H1 detectors reduces the total to a few events of interest. Lacking any further properties reflecting a common excitation by broadband gravitational radiation, we disregarded these as spurious. This new pipeline may be used to systematically search for long-duration chirps in nearby CC-SNe from robotic optical transient surveys using embarrassingly parallel computing.

  6. DIRECTED SEARCHES FOR BROADBAND EXTENDED GRAVITATIONAL WAVE EMISSION IN NEARBY ENERGETIC CORE-COLLAPSE SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Van Putten, Maurice H. P. M., E-mail: mvp@sejong.ac.kr [Room 614, Astronomy and Space Science, Sejong University, 98 Gunja-Dong Gwangin-gu, Seoul 143-747 (Korea, Republic of)

    2016-03-10

    Core-collapse supernovae (CC-SNe) are factories of neutron stars and stellar-mass black holes. SNe Ib/c stand out as potentially originating in relatively compact stellar binaries and they have a branching ratio of about 1% into long gamma-ray bursts. The most energetic events probably derive from central engines harboring rapidly rotating black holes, wherein the accretion of fall-back matter down to the innermost stable circular orbit (ISCO) offers a window into broadband extended gravitational wave emission (BEGE). To search for BEGE, we introduce a butterfly filter in time–frequency space by time-sliced matched filtering. To analyze long epochs of data, we propose using coarse-grained searches followed by high-resolution searches on events of interest. We illustrate our proposed coarse-grained search on two weeks of LIGO S6 data prior to SN 2010br (z = 0.002339) using a bank of up to 64,000 templates of one-second duration covering a broad range in chirp frequencies and bandwidth. Correlating events with signal-to-noise ratios > 6 from the LIGO L1 and H1 detectors reduces the total to a few events of interest. Lacking any further properties reflecting a common excitation by broadband gravitational radiation, we disregarded these as spurious. This new pipeline may be used to systematically search for long-duration chirps in nearby CC-SNe from robotic optical transient surveys using embarrassingly parallel computing.

  7. 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.

  8. THE HIGHLY ENERGETIC EXPANSION OF SN 2010bh ASSOCIATED WITH GRB 100316D

    Energy Technology Data Exchange (ETDEWEB)

    Bufano, Filomena [INAF-Osservatorio Astronomico di Catania, Via Santa Sofia, I-95123, Catania (Italy); Pian, Elena; Turatto, Massimo [INAF-Osservatorio Astronomico di Trieste, Via G.B. Tiepolo 11, I-34143 Trieste (Italy); Sollerman, Jesper [Oskar Klein Centre, Department of Astronomy, AlbaNova, SE-106 91 Stockholm (Sweden); Benetti, Stefano; Valenti, Stefano; Cappellaro, Enrico; Mazzali, Paolo A. [INAF-Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Pignata, Giuliano [Departamento de Ciencias Fisicas, Universidad Andres Bello, Av. Republica 252, Santiago (Chile); Covino, Stefano; D' Avanzo, Paolo; Vergani, Susanna D. [INAF-Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, Merate I-23807 (Italy); Malesani, Daniele; Fynbo, Johan; Hjorth, Jens [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Della Valle, Massimo [INAF-Osservatorio Astronomico di Capodimonte, Salita Moiariello, 16, I-8013 Napoli (Italy); Reichart, Daniel E. [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Campus Box 3255, Chapel Hill, NC 27599-3255 (United States); Starling, Rhaana L. C.; Wiersema, Klass [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Amati, Lorenzo [INAF-Istituto di Astrofisica Spaziale e Fisica cosmica, Via Gobetti 101, I-40129 Bologna (Italy); and others

    2012-07-01

    We present the spectroscopic and photometric evolution of the nearby (z = 0.059) spectroscopically confirmed Type Ic supernova, SN 2010bh, associated with the soft, long-duration gamma-ray burst (X-ray flash) GRB 100316D. Intensive follow-up observations of SN 2010bh were performed at the ESO Very Large Telescope (VLT) using the X-shooter and FORS2 instruments. Thanks to the detailed temporal coverage and the extended wavelength range (3000-24800 A), we obtained an unprecedentedly rich spectral sequence among the hypernovae, making SN 2010bh one of the best studied representatives of this SN class. We find that SN 2010bh has a more rapid rise to maximum brightness (8.0 {+-} 1.0 rest-frame days) and a fainter absolute peak luminosity (L{sub bol} Almost-Equal-To 3 Multiplication-Sign 10{sup 42} erg s{sup -1}) than previously observed SN events associated with GRBs. Our estimate of the ejected {sup 56}Ni mass is 0.12 {+-} 0.02 M{sub Sun }. From the broad spectral features, we measure expansion velocities up to 47,000 km s{sup -1}, higher than those of SNe 1998bw (GRB 980425) and 2006aj (GRB 060218). Helium absorption lines He I {lambda}5876 and He I 1.083 {mu}m, blueshifted by {approx}20,000-30,000 km s{sup -1} and {approx}28,000-38,000 km s{sup -1}, respectively, may be present in the optical spectra. However, the lack of coverage of the He I 2.058 {mu}m line prevents us from confirming such identifications. The nebular spectrum, taken at {approx}186 days after the explosion, shows a broad but faint [O I] emission at 6340 A. The light curve shape and photospheric expansion velocities of SN 2010bh suggest that we witnessed a highly energetic explosion with a small ejected mass (E{sub k} Almost-Equal-To 10{sup 52} erg and M{sub ej} Almost-Equal-To 3 M{sub Sun }). The observed properties of SN 2010bh further extend the heterogeneity of the class of GRB SNe.

  9. The metamorphosis of supernova SN 2008D/XRF 080109: a link between supernovae and GRBs/hypernovae.

    Science.gov (United States)

    Mazzali, Paolo A; Valenti, Stefano; Della Valle, Massimo; Chincarini, Guido; Sauer, Daniel N; Benetti, Stefano; Pian, Elena; Piran, Tsvi; D'Elia, Valerio; Elias-Rosa, Nancy; Margutti, Raffaella; Pasotti, Francesco; Antonelli, L Angelo; Bufano, Filomena; Campana, Sergio; Cappellaro, Enrico; Covino, Stefano; D'Avanzo, Paolo; Fiore, Fabrizio; Fugazza, Dino; Gilmozzi, Roberto; Hunter, Deborah; Maguire, Kate; Maiorano, Elisabetta; Marziani, Paola; Masetti, Nicola; Mirabel, Felix; Navasardyan, Hripsime; Nomoto, Ken'ichi; Palazzi, Eliana; Pastorello, Andrea; Panagia, Nino; Pellizza, L J; Sari, Re'em; Smartt, Stephen; Tagliaferri, Gianpiero; Tanaka, Masaomi; Taubenberger, Stefan; Tominaga, Nozomu; Trundle, Carrie; Turatto, Massimo

    2008-08-29

    The only supernovae (SNe) to show gamma-ray bursts (GRBs) or early x-ray emission thus far are overenergetic, broad-lined type Ic SNe (hypernovae, HNe). Recently, SN 2008D has shown several unusual features: (i) weak x-ray flash (XRF), (ii) an early, narrow optical peak, (iii) disappearance of the broad lines typical of SN Ic HNe, and (iv) development of helium lines as in SNe Ib. Detailed analysis shows that SN 2008D was not a normal supernova: Its explosion energy (E approximately 6x10(51) erg) and ejected mass [ approximately 7 times the mass of the Sun (M(middle dot in circle))] are intermediate between normal SNe Ibc and HNe. We conclude that SN 2008D was originally a approximately 30 M(middle dot in circle) star. When it collapsed, a black hole formed and a weak, mildly relativistic jet was produced, which caused the XRF. SN 2008D is probably among the weakest explosions that produce relativistic jets. Inner engine activity appears to be present whenever massive stars collapse to black holes.

  10. 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.

  11. DISCOVERY OF THE BROAD-LINED TYPE Ic SN 2013cq ASSOCIATED WITH THE VERY ENERGETIC GRB 130427A

    Energy Technology Data Exchange (ETDEWEB)

    Xu, D.; Krühler, T.; Hjorth, J.; Malesani, D.; Fynbo, J. P. U.; Watson, D. J.; Geier, S. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 København Ø (Denmark); De Ugarte Postigo, A.; Thöne, C. C.; Sánchez-Ramírez, R. [Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomía s/n, E-18008 Granada (Spain); Leloudas, G. [The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Cano, Z.; Jakobsson, P. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, IS-107 Reykjavik (Iceland); Schulze, S. [Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile); Kaper, L. [Astronomical Institute Anton Pannekoek, University of Amsterdam, Science Park 904, NL-1098 XH Amsterdam (Netherlands); Sollerman, J. [The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Cabrera-Lavers, A. [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Cao, C. [Department of Space Science and Physics, Shandong University at Weihai, Weihai, Shandong 264209 (China); Covino, S. [INAF/Brera Astronomical Observatory, via Bianchi 46, I-23807 Merate (Italy); Flores, H., E-mail: dong@dark-cosmology.dk [Laboratoire Galaxies Etoiles Physique et Instrumentation, Observatoire de Paris, 5 place Jules Janssen, F-92195 Meudon (France); and others

    2013-10-20

    Long-duration gamma-ray bursts (GRBs) at z < 1 are found in most cases to be accompanied by bright, broad-lined Type Ic supernovae (SNe Ic-BL). The highest-energy GRBs are mostly located at higher redshifts, where the associated SNe are hard to detect observationally. Here, we present early and late observations of the optical counterpart of the very energetic GRB 130427A. Despite its moderate redshift, z = 0.3399 ± 0.0002, GRB 130427A is at the high end of the GRB energy distribution, with an isotropic-equivalent energy release of E{sub iso} ∼ 9.6 × 10{sup 53} erg, more than an order of magnitude more energetic than other GRBs with spectroscopically confirmed SNe. In our dense photometric monitoring, we detect excess flux in the host-subtracted r-band light curve, consistent with that expected from an emerging SN, ∼0.2 mag fainter than the prototypical SN 1998bw. A spectrum obtained around the time of the SN peak (16.7 days after the GRB) reveals broad undulations typical of SNe Ic-BL, confirming the presence of an SN, designated SN 2013cq. The spectral shape and early peak time are similar to those of the high expansion velocity SN 2010bh associated with GRB 100316D. Our findings demonstrate that high-energy, long-duration GRBs, commonly detected at high redshift, can also be associated with SNe Ic-BL, pointing to a common progenitor mechanism.

  12. Spectroscopic classification of PTSS-17xqa (SN 2017him) as a type Ia supernova

    Science.gov (United States)

    Zhang, J.-J.; Xu, L.; Wang, X. F.; Li, W.-X.; Tan, H.-J.; Li, B.; Xu, Z.-J.; Zhao, H.-B.; Wang, L.-F.; Xiang, D.-F.; Rui, L.-M.; Lin, H.

    2017-10-01

    We obtained an optical spectrum (range 360-870 nm) of PTSS-17xqa (SN 2017him), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT 2017 Oct. 29.7 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at Li-Jiang Observatory of Yunnan Observatories.

  13. Stringent radio constraint on the exceptional super-luminous supernova SN2017egm

    Science.gov (United States)

    Romero-Canizales, Cristina; Beswick, Robert; Dong, Subo; Prieto, Jose L.

    2017-06-01

    We report radio observations of supernova SN2017egm (TNS Discovery Report, 591) at 10GHz with the Very Large Array (VLA; project 17A-464) on UT 22.9 June 2017, and at 1.5GHz with the electronic Multi-Element Remotely-Linked Interferometer Network (e-MERLIN) on UT 21 to 22 June 2017.

  14. Spectroscopic classification of PTSS-17ygs (SN 2017hqc) as a type Ia supernova

    Science.gov (United States)

    Zhang, J.-J.; Xu, L.; Wang, X. F.; Li, W.-X.; Tan, H.-J.; Li, B.; Xu, Z.-J.; Zhao, H.-B.; Wang, L.-F.; Xiang, D.-F.; Rui, L.-M.; Yang, Z.-S.

    2017-10-01

    We obtained an optical spectrum (range 360-870 nm) of PTSS-17ygs (SN 2017hqc), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT 2017 Oct. 28.5 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at Li-Jiang Observatory of Yunnan Observatories.

  15. Spectroscopic classification of PTSS-17zix (SN 2017hxu) as a type IIP supernova

    Science.gov (United States)

    Zhang, J.-J.; Zhang, X.-L.; Wang, F. X.; Li, W.-X.; Tan, H.-J.; Li, B.; Xu, Z.-J.; Zhao, H.-B.; Wang, L.-F.; Xiang, D.-F.; Rui, L.-M.; Lin, H.

    2017-11-01

    We obtained an optical spectrum (range 350-900 nm) of PTSS-17zix (SN 2017hxu), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT 2017 Nov. 12.7 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at Li-Jiang Observatory of Yunnan Observatories.

  16. Spectral classification of PTSS-17baux (SN 2017imr) as a type IIP supernova

    Science.gov (United States)

    Zhang, J.-J.; Xu, L.; Wang, X. F.; Li, W.-X.; Tan, H.-J.; Li, B.; Xu, Z.-J.; Zhao, H.-B.; Wang, L.-F.; Xiang, D.-F.; Rui, L.-M.; Lin, H.

    2017-11-01

    We obtained an optical spectrum (range 350-890 nm) of PTSS-17baux (SN 2017imr), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT 2017 Nov. 28.7 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at Li-Jiang Observatory of Yunnan Observatories.

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

    Science.gov (United States)

    Lin, Han; Wang, Xiaofeng; Xiang, Danfeng; LI, Wenxiong; Rui, Liming; Wu, Hong; Qiu, Peng; Xu, Zhijian; Li, Bin; Zhao, Haibin; Wang, Lifan; Zhang, Jujia; Zhang, Tianmeng

    2017-11-01

    We obtained an optical spectrum (range 360-840 nm) of SN 2017hqf(PTSS-17ygv), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT 2017 Nov. 16.85 with the Xinglong 2.16 m telescope (BFOSC) at Xinglong Observatory of NAOC.

  18. Spectroscopic classification of PTSS-17bazc (SN 2017imx) as a type Ia supernova

    Science.gov (United States)

    Zhang, J.-J.; Xu, L.; F., X.; Wang; -X., W.; Li; Tan, H.-J.; Li, B.; Xu, Z.-J.; Zhao, H.-B.; Wang, L.-F.; Xiang, D.-F.; Rui, L.-M.; Lin, H.

    2017-11-01

    We obtained an optical spectrum (range 350-890 nm) of PTSS-17bazc (SN 2017imx),?discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT 2017 Nov. 26.7 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at Li-Jiang Observatory of Yunnan Observatories.

  19. SN2005da: A Spectroscopic and Photometric Analysis of a Peculiar Type Ic Supernova

    Science.gov (United States)

    Williamson, Jacob

    2017-12-01

    Core collapse supernovae are an important class of objects in stellar evolution research as they are the final life stage of high mass stars. Supernovae in general are classified into several spectral types; this paper explores SN 2005da, classified as a Type Ic, meaning it lacks hydrogen and helium lines. The supernova was originally classified as a broad-lined Type Ic (Type Ic-BL), with expansion velocities near maximum light greater than or approximately equal to 15000 km/s. However, some of the elements present in the spectrum, namely carbon and oxygen, have narrower lines (FWHM approximately equal to 2300 km/s) than other elements, indicating an interaction with a previously ejected envelope. The supernova is also found to have a decay time, with a change in magnitude over 15 days following maximum light of about 1.4 magnitudes, that is significantly faster than typical Type Ic or Ic-BL. This is more akin to a rarer object type known as a Type Ibn, although it lacks the characteristic narrow helium lines of this type. Therefore, SN 2005da appears to be unlike known examples of Type Ic supernovae.

  20. 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.

  1. Modeling The Most Luminous Supernova Associated with a Gamma-Ray Burst, SN 2011kl

    Science.gov (United States)

    Wang, Shan-Qin; Cano, Zach; Wang, Ling-Jun; Zheng, WeiKang; Dai, Zi-Gao; Filippenko, Alexei V.; Liu, Liang-Duan

    2017-12-01

    We study the most luminous known supernova (SN) associated with a gamma-ray burst (GRB), SN 2011kl. The photospheric velocity of SN 2011kl around peak brightness is 21,000 ± 7000 km s-1. Owing to different assumptions related to the light-curve (LC) evolution (broken or unbroken power-law function) of the optical afterglow of GRB 111209A, different techniques for the LC decomposition, and different methods (with or without a near-infrared contribution), three groups derived three different bolometric LCs for SN 2011kl. Previous studies have shown that the LCs without an early-time excess preferred a magnetar model, a magnetar+56Ni model, or a white dwarf tidal disruption event model rather than the radioactive heating model. On the other hand, the LC shows an early-time excess and dip that cannot be reproduced by the aforementioned models, and hence the blue-supergiant model was proposed to explain it. Here, we reinvestigate the energy sources powering SN 2011kl. We find that the two LCs without the early-time excess of SN 2011kl can be explained by the magnetar+56Ni model, and the LC showing the early excess can be explained by the magnetar+56Ni model taking into account the cooling emission from the shock-heated envelope of the SN progenitor, demonstrating that this SN might primarily be powered by a nascent magnetar.

  2. 44Ti radioactivity in young supernova remnants: Cas A and SN 1987A

    OpenAIRE

    Motizuki, Yuko; Kumagai, Shiomi

    2003-01-01

    We investigate radioactivity from the decay sequence of 44Ti in young supernova remnants (SNRs), Cassiopeia A (Cas A) and SN 1987A. It is shown by a linear analysis that ionization of 44Ti, a pure electron capture decay isotope, affects the radioactivity contradistinctively in these two SNRs: Ionization of 44Ti to H-like and He-like states enhances its present radioactivity in Cas A, while such high-ionization decreases its radioactivity in SN 1987A. We briefly discuss the enhancement factor ...

  3. 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.

  4. 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.

  5. 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

  6. The KARMEN anomaly, light neutralinos and supernova SN1987A

    CERN Document Server

    Kachelriess, M

    2000-01-01

    The KARMEN experiment observes a time anomaly in events induced by pion decay at rest. This anomaly can be ascribed to the production of a new weakly interacting particle X with mass m_X\\sim 34 MeV. We show that a recently proposed identification of the X particle with the lightest neutralino \\chi in the frame work of the MSSM with broken R parity is in contradiction to optical observations of SN 1987A.

  7. SN1987A: The Birth of a Supernova Remnant

    Science.gov (United States)

    McCray, Richard

    2003-01-01

    This grant was intended to support the development of theoretical models needed to interpret and understand the observations by the Hubble Space Telescope and the Chandra X-ray telescope of the rapidly developing remnant of Supernova 1987A. In addition, we carried out a few investigations of related topics. The project was spectacularly successful. The models that we developed provide the definitive framework for predicting and interpreting this phenomenon. Following is a list of publications based on our work. Some of these papers include results of both theoretical modeling supported by this project and also analysis of data supported by the Space Telescope Science Institute and the Chandra X-ray Observatory. We first list papers published in refereed journals, then conference proceedings and book chapters, and also an educational web site.

  8. Optical and IR observations of SN 2013L, a Type IIn Supernova surrounded by asymmetric CSM

    Science.gov (United States)

    Andrews, Jennifer E.; Smith, Nathan; McCully, Curtis; Fox, Ori D.; Valenti, S.; Howell, D. A.

    2017-11-01

    We present optical and near-IR photometry and spectroscopy of SN 2013L for the first 4 yr post-explosion. SN 2013L was a moderately luminous (Mr = -19.0) Type IIn supernova (SN) that showed signs of strong shock interaction with the circumstellar medium (CSM). The CSM interaction was equal to or stronger to SN 1988Z for the first 200 d and is observed at all epochs after explosion. Optical spectra revealed multicomponent hydrogen lines appearing by day 33 and persisting and slowly evolving over the next few years. By day 1509, the H α emission was still strong and exhibiting multiple peaks, hinting that the CSM was in a disc or torus around the SN. SN 2013L is part of a growing subset of SNe IIn that shows both strong CSM interaction signatures and the underlying broad lines from the SN ejecta photosphere. The presence of a blue H α emission bump and a lack of a red peak does not appear to be due to dust obscuration since an identical profile is seen in Pa β. Instead this suggests a high concentration of material on the near-side of the SN or a disc inclination of roughly edge-on and hints that SN 2013L was part of a massive interactive binary system. Narrow H α P-Cygni lines that persist through the entirety of the observations measure a progenitor outflow speed of 80-130 km s-1, speeds normally associated with extreme red supergiants, yellow hypergiants, or luminous blue variable winds. This progenitor scenario is also consistent with an inferred progenitor mass-loss rate of 0.3-8.0 × 10-3 M⊙ yr-1.

  9. 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.

  10. 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.

  11. SN 2017dio: A Type-Ic Supernova Exploding in a Hydrogen-rich Circumstellar Medium

    Science.gov (United States)

    Kuncarayakti, Hanindyo; Maeda, Keiichi; Ashall, Christopher J.; Prentice, Simon J.; Mattila, Seppo; Kankare, Erkki; Fransson, Claes; Lundqvist, Peter; Pastorello, Andrea; Leloudas, Giorgos; Anderson, Joseph P.; Benetti, Stefano; Bersten, Melina C.; Cappellaro, Enrico; Cartier, Régis; Denneau, Larry; Della Valle, Massimo; Elias-Rosa, Nancy; Folatelli, Gastón; Fraser, Morgan; Galbany, Lluís; Gall, Christa; Gal-Yam, Avishay; Gutiérrez, Claudia P.; Hamanowicz, Aleksandra; Heinze, Ari; Inserra, Cosimo; Kangas, Tuomas; Mazzali, Paolo; Melandri, Andrea; Pignata, Giuliano; Rest, Armin; Reynolds, Thomas; Roy, Rupak; Smartt, Stephen J.; Smith, Ken W.; Sollerman, Jesper; Somero, Auni; Stalder, Brian; Stritzinger, Maximilian; Taddia, Francesco; Tomasella, Lina; Tonry, John; Weiland, Henry; Young, David R.

    2018-02-01

    SN 2017dio shows both spectral characteristics of a type-Ic supernova (SN) and signs of a hydrogen-rich circumstellar medium (CSM). Prominent, narrow emission lines of H and He are superposed on the continuum. Subsequent evolution revealed that the SN ejecta are interacting with the CSM. The initial SN Ic identification was confirmed by removing the CSM interaction component from the spectrum and comparing with known SNe Ic and, reversely, adding a CSM interaction component to the spectra of known SNe Ic and comparing them to SN 2017dio. Excellent agreement was obtained with both procedures, reinforcing the SN Ic classification. The light curve constrains the pre-interaction SN Ic peak absolute magnitude to be around {M}g=-17.6 mag. No evidence of significant extinction is found, ruling out a brighter luminosity required by an SN Ia classification. These pieces of evidence support the view that SN 2017dio is an SN Ic, and therefore the first firm case of an SN Ic with signatures of hydrogen-rich CSM in the early spectrum. The CSM is unlikely to have been shaped by steady-state stellar winds. The mass loss of the progenitor star must have been intense, \\dot{M}∼ 0.02{({ε }{{H}α }/0.01)}-1 ({v}{wind}/500 km s‑1) ({v}{shock}/10,000 km s‑1)‑3 M ⊙ yr‑1, peaking at a few decades before the SN. Such a high mass-loss rate might have been experienced by the progenitor through eruptions or binary stripping. Based on observations made with the NOT, operated by the Nordic Optical Telescope Scientific Association at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. This work is based (in part) on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile as part of PESSTO, (the Public ESO Spectroscopic Survey for Transient Objects Survey) ESO program 188.D-3003, 191.D-0935, 197.D-1075. Based on observations made with the Liverpool Telescope operated on the

  12. Re-examination of the Expected gamma-ray emission of supernova remnant SN 1987A

    OpenAIRE

    Berezhko, E; Ksenofontov, L.; Völk, H.

    2015-01-01

    A nonlinear kinetic theory, combining cosmic-ray (CR) acceleration in supernova remnants (SNRs) with their gas dynamics, is used to re-examine the nonthermal properties of the remnant of SN 1987A for an extended evolutionary period of 5-50 yr. This spherically symmetric model is approximately applied to the different features of the SNR which consist of (i) a blue supergiant wind and bubble, and (ii) of the swept-up red supergiant (RSG) wind structures in the form of an H II region, an equato...

  13. The End of Amnesia: Measuring the Metallicities of Type Ia SN Progenitors with Manganese Lines in Supernova Remnants

    Science.gov (United States)

    Badenes, Carles; Bravo, Eduardo; Hughes, John P.

    2009-05-01

    The Mn to Cr mass ratio in supernova ejecta has recently been proposed as a tracer of Type Ia SN progenitor metallicity. We review the advantages and problems of this observable quantity, and discuss them in the framework of the Tycho Supernova Remnant. The fluxes of the Mn and Cr Kα lines in the X-ray spectra of Tycho observed by the Suzaku satellite suggests a progenitors of supersolar metallicity.

  14. 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 (< 15 years) reflect the structure of outer ejecta. At later epochs, the shape of X-ray lightcurves and spectra reflect the density structure of the nebula around SN 1987A. This enabled us to ascertain the origin of the multi-thermal X-ray emission, to disentangle the imprint of the supernova on the remnant emission from the effects of the remnant interaction with the 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.

  15. Spectroscopic classification of PTSS-17xsq (SN 2017hng) as a young 91T-like type Ia supernova

    Science.gov (United States)

    Zhang, J.-J.; Wang, J.-G.; Wang, F.-X.; Li, W.-X.; Tan, H.-J.; Li, B.; Xu, Z.-J.; Zhao, H.-B.; Wang, L.-F.; Xiang, D.-F.; Rui, L.-M.; Yang, Z.-S.

    2017-10-01

    We obtained an optical spectrum (range 380-880 nm) of PTSS-17xsq (SN 2017hng), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT 2017 Oct. 25.7 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at Li-Jiang Observatory of Yunnan Observatories.

  16. 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.

  17. Supernovae 2016bdu and 2005gl, and their link with SN 2009ip-like transients: another piece of the puzzle

    DEFF Research Database (Denmark)

    Pastorello, A.; Kochanek, C. S.; Fraser, M.

    2018-01-01

    Supernova (SN) 2016bdu is an unusual transient resembling SN 2009ip. SN 2009ip-like events are characterized by a long-lasting phase of erratic variability which ends with two luminous outbursts a few weeks apart. The second outburst is significantly more luminous (about 3 mag) than the first. In...

  18. Type II Supernova Energetics and Comparison of Light Curves to Shock-Cooling Models

    Science.gov (United States)

    Rubin, Adam; Gal-Yam, Avishay; Cia, Annalisa De; Horesh, Assaf; Khazov, Danny; Ofek, Eran O.; Kulkarni, S. R.; Arcavi, Iair; Manulis, Ilan; Cenko, S. Bradley

    2016-01-01

    During the first few days after explosion, Type II supernovae (SNe) are dominated by relatively simple physics. Theoretical predictions regarding early-time SN light curves in the ultraviolet (UV) and optical bands are thus quite robust. We present, for the first time, a sample of 57 R-band SN II light curves that are well-monitored during their rise, with greater than 5 detections during the first 10 days after discovery, and a well-constrained time of explosion to within 13 days. We show that the energy per unit mass (E/M) can be deduced to roughly a factor of five by comparing early-time optical data to the 2011 model of Rabinak Waxman, while the progenitor radius cannot be determined based on R-band data alone. We find that SN II explosion energies span a range of EM = (0.2-20) x 10(exp 51) erg/(10 M stellar mass), and have a mean energy per unit mass of E/ M = 0.85 x 10(exp 51) erg(10 stellar mass), corrected for Malmquist bias. Assuming a small spread in progenitor masses, this indicates a large intrinsic diversity in explosion energy. Moreover, E/M is positively correlated with the amount of Ni-56 produced in the explosion, as predicted by some recent models of core-collapse SNe. We further present several empirical correlations. The peak magnitude is correlated with the decline rate (Delta m(sub15), the decline rate is weakly correlated with the rise time, and the rise time is not significantly correlated with the peak magnitude. Faster declining SNe are more luminous and have longer rise times. This limits the possible power sources for such events.

  19. 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.

  20. OGLE-2013-SN-079: A Lonely Supernova Consistent with a Helium Shell Detonation

    Science.gov (United States)

    Inserra, C.; Sim, S. A.; 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.; Kozłowski, S.; Kromer, M.; Lyman, J. D.; Polshaw, J.; Röpke, F. K.; Ruiter, A. J.; Smith, K.; Spiro, S.; Sullivan, M.; Yaron, O.; Young, D.; Yuan, F.

    2015-01-01

    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 MI ~ -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.

  1. Far-UV HST Spectroscopy of An Unusual Hydrogen Poor Superluminous Supernova: SN2017egm

    Science.gov (United States)

    Yan, Lin; Perley, Daniel; Quimby, Robert; De Cia, Annalisa; Brown, Peter

    2018-01-01

    SN2017egm is the closest (z=0.03) H-poor superluminous supernova (SLSN-I) detected to date, and a rare example of an SLSN in a massive and metal-rich galaxy. Here we present the HST UV & optical spectra covering (1000 - 5500)A taken at +3day relative to the peak. Our data reveal two sets of absorption systems, separated by 235km/s, at redshifts matching NGC3191 and its companion galaxy 73arcsec apart. A weakly damped Lyman-alpha absorption line (sub-DLA) is also detected with a total column density of N(HI) ~(6^{+3}_{-1})e+19}cm^-2. This is an order of magnitude smaller than HI column densities in nearby massive disk galaxies (>10^{10}Msun) and suggests that SN2017egm is on the near side of the galaxy mid-plane and its local environment on a 5 parsec is highly ionized due to photo-ionization by SN2017egm. The low HI column density also implies a low host dust extinction for SN2017egm, E(B-V) of 0.007. We constrain the gas metallicity using unsaturated absorption lines (SII1253 and FeII1629). Taking into account of ionization and dust depletion corrections, we find that the metal abundances for both sets of absorbers are close to be 1Zsun or more, and our data can rule out metallicity below 0.5Zsun. We make a comparative analysis of high-quality, early-time UV spectra of four SLSNe-I, SN2017egm, Gaia16apd, PTF12dam and iPTF13ajg. We find that although they have similar blackbody temperatures, the shape of their UV continuum (1000 - 3000A) varies significantly, with the 1400A to 2800A continuum ratio of 1.5 for Gaia16apd to 0.4 for iPTF13ajg. This variation can not be explained by the magnetar power alone as claimed before, and is likely to do with sizes and compositions of the photosphere. We conclude that a single UV SED is not sufficient when modeling SLSN-I light curves. In addition, there are a common set of seven UV absorption features between 1000A and 2800A, including three new ones in the far-UV spectra of SN2017egm and Gaia16apd. Using syn++ synthetic

  2. 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.

  3. Modelling the Type Ic SN 2004aw: a moderately energetic explosion of a massive C+O star without a GRB

    Science.gov (United States)

    Mazzali, P. A.; Sauer, D. N.; Pian, E.; Deng, J.; Prentice, S.; Ben Ami, S.; Taubenberger, S.; Nomoto, K.

    2017-08-01

    An analysis of the Type Ic supernova (SN) 2004aw is performed by means of models of the photospheric and nebular spectra and of the bolometric light curve. SN 2004aw is shown not to be 'broad-lined', contrary to previous claims, but rather a 'fast-lined' SN Ic. The spectral resemblance to the narrow-lined Type Ic SN 1994I, combined with the strong nebular [O i] emission and the broad light curve, points to a moderately energetic explosion of a massive C+O star. The ejected 56Ni mass is ≈0.20 M⊙. The ejecta mass as constrained by the models is ∼3-5 M⊙, while the kinetic energy is estimated as EK ∼3-6 × 1051 erg. The ratio EK/M⊙, the specific energy that influences the shape of the spectrum, is therefore ≈1. The corresponding zero-age main-sequence mass of the progenitor star may have been ∼23-28 M⊙. Tests show that a flatter outer density structure may have caused a broad-lined spectrum at epochs before those observed without affecting the later epochs when data are available, implying that our estimate of EK is a lower limit. SN 2004aw may have been powered by either a collapsar or a magnetar, both of which have been proposed for gamma-ray burst SNe. Evidence for this is seen in the innermost layers, which appear to be highly aspherical as suggested by the nebular line profiles. However, any engine was not extremely powerful, as the outer ejecta are more consistent with a spherical explosion and no gamma-ray burst was detected in coincidence with SN 2004aw.

  4. THE SPECTRAL SN-GRB CONNECTION: SYSTEMATIC SPECTRAL COMPARISONS BETWEEN TYPE Ic SUPERNOVAE AND BROAD-LINED TYPE Ic SUPERNOVAE WITH AND WITHOUT GAMMA-RAY BURSTS

    Energy Technology Data Exchange (ETDEWEB)

    Modjaz, Maryam; Liu, Yuqian Q.; Bianco, Federica B.; Graur, Or, E-mail: mmodjaz@nyu.edu [Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)

    2016-12-01

    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 11 SNe Ic-bl with GRBs (SN-GRBs) as a function of time in order to probe their explosion conditions and progenitors. Using a number of novel methods, we analyze a total of 407 spectra, which were drawn from published spectra of individual SNe as well as from the densely time-sampled spectra 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. We find that SN 1994I is not a typical SN Ic, contrasting the general view, 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 using a new method described here and find that SNe Ic-bl with GRBs, on average, have quantifiably higher absorption velocities, as well as broader line widths than SNe without observed GRBs. In addition, we search for correlations between SN-GRB spectral properties and the energies of their accompanying GRBs. Finally, we show that the absence of clear He lines in optical spectra of SNe Ic-bl, and in particular of SN-GRBs, is not due to them being too smeared-out due to the high velocities present in the ejecta. This implies that the progenitor stars of SN-GRBs are probably free of the He-layer, in addition to being H-free, which puts strong constraints on the stellar evolutionary paths needed to produce such SN-GRB progenitors at the observed low metallicities.

  5. 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.

  6. SN 2016jhj at redshift 0.34: extending the Type II supernova Hubble diagram using the standard candle method

    Science.gov (United States)

    de Jaeger, T.; Galbany, L.; Filippenko, A. V.; González-Gaitán, S.; Yasuda, N.; Maeda, K.; Tanaka, M.; Morokuma, T.; Moriya, T. J.; Tominaga, N.; Nomoto, K.; Komiyama, Y.; Anderson, J. P.; Brink, T. G.; Carlberg, R. G.; Folatelli, G.; Hamuy, M.; Pignata, G.; Zheng, W.

    2017-12-01

    Although Type Ia supernova cosmology has now reached a mature state, it is important to develop as many independent methods as possible to understand the true nature of dark energy. Recent studies have shown that Type II supernovae (SNe II) offer such a path and could be used as alternative distance indicators. However, the majority of these studies were unable to extend the Hubble diagram above redshift z = 0.3 because of observational limitations. Here, we show that we are now ready to move beyond low redshifts and attempt high-redshift (z ≳ 0.3) SN II cosmology as a result of new-generation deep surveys such as the Subaru/Hyper Suprime-Cam survey. Applying the 'standard candle method' to SN 2016jhj (z = 0.3398 ± 0.0002; discovered by HSC) together with a low-redshift sample, we are able to construct the highest-redshift SN II Hubble diagram to date with an observed dispersion of 0.27 mag (i.e. 12-13 per cent in distance). This work demonstrates the bright future of SN II cosmology in the coming era of large, wide-field surveys like that of the Large Synoptic Survey Telescope.

  7. Re-examination of the Expected Gamma-Ray Emission of Supernova Remnant SN 1987A

    Science.gov (United States)

    Berezhko, E. G.; Ksenofontov, L. T.; Völk, H. J.

    2015-09-01

    A nonlinear kinetic theory, combining cosmic-ray (CR) acceleration in supernova remnants (SNRs) with their gas dynamics, is used to re-examine the nonthermal properties of the remnant of SN 1987A for an extended evolutionary period of 5-50 year. This spherically symmetric model is approximately applied to the different features of the SNR, consisting of (i) a blue supergiant wind and bubble, and (ii) of the swept-up red supergiant (RSG) wind structures in the form of an H ii region, an equatorial ring (ER), and an hourglass region. The RSG wind involves a mass loss rate that decreases significantly with elevation above and below the equatorial plane. The model adapts recent three-dimensional hydrodynamical simulations by Potter et al. in 2014 that use a significantlysmaller ionized mass of the ER than assumed in the earlier studies by the present authors. The SNR shock recently swept up the ER, which is the densest region in the immediate circumstellar environment. Therefore, the expected gamma-ray energy flux density at TeV energies in the current epoch has already reached its maximal value of ˜10-13 erg cm-2 s-1. This flux should decrease by a factor of about two over the next 10 years.

  8. Expected Gamma-Ray Emission of Supernova Remnant SN 1987A

    Science.gov (United States)

    Berezhko, E. G.; Ksenofontov, L. T.; Völk, H. J.

    2011-05-01

    A nonlinear kinetic theory of cosmic ray (CR) acceleration in supernova remnants (SNRs) is employed to re-examine the nonthermal properties of the remnant of SN 1987A for an extended evolutionary period of 5-100 yr. It is shown that an efficient production of nuclear CRs leads to a strong modification of the outer SNR shock and to a large downstream magnetic field B d ≈ 20 mG. The shock modification and the strong field are required to yield the steep radio emission spectrum observed, as well as the considerable synchrotron cooling of high-energy electrons which diminishes their X-ray synchrotron flux. These features are also consistent with the existing X-ray observations. The expected γ-ray energy flux at TeV energies at the current epoch is nearly epsilonγ F γ ≈ 4 × 10-13 erg cm2 s-1 under reasonable assumptions about the overall magnetic field topology and the turbulent perturbations of this field. The general nonthermal strength of the source is expected to increase roughly by a factor of two over the next 15-20 years thereafter, it should decrease with time in a secular form.

  9. GRB 161219B/SN 2016jca: A low-redshift gamma-ray burst supernova powered by radioactive heating

    Science.gov (United States)

    Cano, Z.; Izzo, L.; de Ugarte Postigo, A.; Thöne, C. C.; Krühler, T.; Heintz, K. E.; Malesani, D.; Geier, S.; Fuentes, C.; Chen, T.-W.; Covino, S.; D'Elia, V.; Fynbo, J. P. U.; Goldoni, P.; Gomboc, A.; Hjorth, J.; Jakobsson, P.; Kann, D. A.; Milvang-Jensen, B.; Pugliese, G.; Sánchez-Ramírez, R.; Schulze, S.; Sollerman, J.; Tanvir, N. R.; Wiersema, K.

    2017-09-01

    Since the first discovery of a broad-lined type Ic supernova (SN) with a long-duration gamma-ray burst (GRB) in 1998, fewer than fifty GRB-supernovae (SNe) have been discovered. The intermediate-luminosity Swift GRB 161219B and its associated supernova SN 2016jca, which occurred at a redshift of z = 0.1475, represents only the seventh GRB-SN to have been discovered within 1 Gpc, and hence provides an excellent opportunity to investigate the observational and physical properties of these very elusive and rare type of SN. As such, we present optical to near-infrared photometry and optical spectroscopy of GRB 161219B and SN 2016jca, spanning the first three months since its discovery. GRB 161219B exploded in the disk of an edge-on spiral galaxy at a projected distance of 3.4 kpc from the galactic centre. GRB 161219B itself is an outlier in the Ep,I - Eγ,iso plane, while SN 2016jca had a rest-frame, peak absolute V-band magnitude of MV = - 19.0 ± 0.1, which it reached after 12.3 ± 0.7 rest-frame days. We find that the bolometric properties of SN 2016jca are inconsistent with being powered solely by a magnetar central engine, and demonstrate that it was likely powered exclusively by energy deposited by the radioactive decay of nickel and cobalt into their daughter products, which were nucleosynthesised when its progenitor underwent core collapse. We find that 0.22 ± 0.08M⊙ of nickel is required to reproducethe peak luminosity of SN 2016jca, and we constrain an ejecta mass of 5.8 ± 0.3M⊙ and a kinetic energy of 5.1 ± 0.8 × 1052 erg. Finally, we report on a chromatic, pre-maximum bump in the g-band light curve, and discuss its possible origin.

  10. 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.

  11. SN 2007bg: the complex circumstellar medium around one of the most radio-luminous broad-lined Type Ic supernovae

    Science.gov (United States)

    Salas, P.; Bauer, F. E.; Stockdale, C.; Prieto, J. L.

    2013-01-01

    In this paper we present the results of the radio light curve and X-ray observations of broad-lined Type Ic (Ic-BL) SN 2007bg. The light curve shows three distinct phases of spectral and temporal evolution, implying that the supernova (SN) shock likely encountered at least three different circumstellar medium regimes. We interpret this as the progenitor of SN 2007bg having at least two distinct mass-loss episodes (i.e. phases 1 and 3) during its final stages of evolution, yielding a highly stratified circumstellar medium. Modelling the phase 1 light curve as a freely expanding, synchrotron-emitting shell, self-absorbed by its own radiating electrons, requires a progenitor mass-loss rate of skew4dot{M}≈ 1.9× 10^{-6}(v_w/1000 km s^{-1}) M⊙ yr-1 for the last t ˜ 20(vw/1000 km s-1) yr before explosion and a total energy of the radio-emitting ejecta of E ≈ 1 × 1048 erg 10 d after explosion. This places SN 2007bg among the most energetic Type Ib/c events. We interpret the second phase as a sparser `gap' region between the two winds stages. Phase 3 shows a second absorption turn-on before rising to a peak luminosity 2.6 times higher than in phase 1. Assuming this luminosity jump is due to a circumstellar medium density enhancement from a faster previous mass-loss episode, we estimate that the phase 3 mass-loss rate could be as high as skew4dot{M}lesssim 4.3× 10^{-4}(v_w/1000 km s^{-1}) M⊙ yr-1. The phase 3 wind would have transitioned directly into the phase 1 wind for a wind speed difference of ≈2. In summary, the radio light curve provides robust evidence for dramatic global changes in at least some Ic-BL progenitors just prior (˜10-1000 yr) to explosion. The observed luminosity of this SN is the highest observed for a non-gamma-ray-burst Ic-BL SN, reaching L8.46 GHz ≈ 1 × 1029 erg Hz-1 s-1, ˜567 d after explosion.

  12. Blue supergiant progenitors from binary mergers for SN 1987A and other Type II-peculiar supernovae

    Science.gov (United States)

    Menon, Athira; Heger, Alexander

    2017-11-01

    We present results of a systematic and detailed stellar evolution study of binary mergers for blue supergiant (BSG) progenitors of Type II supernovae, particularly for SN 1987A. We are able to reproduce nearly all observational aspects of the progenitor of SN 1987A, Sk -69 °202, such as its position in the HR diagram, the enrichment of helium and nitrogen in the triple-ring nebula and its lifetime before its explosion. We build our evolutionary model based on the merger model of Podsiadlowski et al. (1992), Podsiadlowski et al. (2007) and empirically explore an initial parameter consisting of primary masses, secondary masses and different depths up to which the secondary penetrates the He core during the merger. The evolution of the post-merger star is continued until just before iron-core collapse. Of the 84 pre-supernova models (16 M⊙ - 23 M⊙) computed, the majority of the pre-supernova models are compact, hot BSGs with effective temperature >12 kK and 30 R⊙ - 70 R⊙ of which six match nearly all the observational properties of Sk -69 °202.

  13. 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.

  14. 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.

  15. The late-time light curve of the Type Ia supernova SN 2011fe

    Science.gov (United States)

    Dimitriadis, G.; Sullivan, M.; Kerzendorf, W.; Ruiter, A. J.; Seitenzahl, I. R.; Taubenberger, S.; Doran, G. B.; Gal-Yam, A.; Laher, R. R.; Maguire, K.; Nugent, P.; Ofek, E. O.; Surace, J.

    2017-07-01

    We present late-time optical R-band imaging data from the Palomar Transient Factory (PTF) for the nearby Type Ia supernova SN 2011fe. The stacked PTF light curve provides densely sampled coverage down to R ≃ 22 mag over 200-620 d past explosion. Combining with literature data, we estimate the pseudo-bolometric light curve for this event from 200 to 1600 d after explosion, and constrain the likely near-infrared (Near-IR) contribution. This light curve shows a smooth decline consistent with radioactive decay, except over ˜450 to ˜600 d where the light curve appears to decrease faster than expected based on the radioactive isotopes presumed to be present, before flattening at around 600 d. We model the 200-1600 d pseudo-bolometric light curve with the luminosity generated by the radioactive decay chains of 56Ni, 57Ni and 55Co, and find it is not consistent with models that have full positron trapping and no infrared catastrophe (IRC); some additional energy escape other than optical/near-IR photons is required. However, the light curve is consistent with models that allow for positron escape (reaching 75 per cent by day 500) and/or an IRC (with 85 per cent of the flux emerging in non-optical wavelengths by day 600). The presence of the 57Ni decay chain is robustly detected, but the 55Co decay chain is not formally required, with an upper mass limit estimated at 0.014 M⊙. The measurement of the 57Ni/56Ni mass ratio is subject to significant systematic uncertainties, but all of our fits require a high ratio >0.031 (>1.3 in solar abundances).

  16. Nonthermal Emission of Supernova Remnant SN 1006 Revisited: Theoretical Model and the H.E.S.S. Results

    Science.gov (United States)

    Berezhko, E. G.; Ksenofontov, L. T.; Völk, H. J.

    2012-11-01

    The properties of the Galactic supernova remnant (SNR) SN 1006 are theoretically re-analyzed in light of the recent H.E.S.S. results. Nonlinear kinetic theory is used to determine the momentum spectrum of cosmic rays (CRs) in space and time in the supernova remnant SN 1006. The physical parameters of the model—proton injection rate, electron-to-proton ratio, and downstream magnetic field strength—are determined through a fit of the result to the observed spatially integrated synchrotron emission properties. The only remaining unknown astronomical parameter, the circumstellar gas number density, is determined by a normalization of the amplitude of the γ-ray flux to the observed amplitude. The bipolar morphology of both nonthermal X-ray and γ-ray emissions is explained by the preferential injection of suprathermal nuclei and subsequent magnetic field amplification in the quasi-parallel regions of the outer supernova shock. The above parameters provide an improved fit to all existing nonthermal emission data, including the TeV emission spectrum recently detected by H.E.S.S., with the circumstellar hydrogen gas number density N H ≈ 0.06 cm-3 close to values derived from observations of thermal X-rays. The hadronic and leptonic γ-ray emissions are of comparable strength. The overall energy of accelerated CRs at the present epoch is of the order of 5% of the total hydrodynamic explosion energy, and is predicted to rise with time by a factor of ≈2. The relevance of CR escape from the SNR for the spectrum of the γ-ray emission is demonstrated. The sum of the results suggests that SN 1006 is a CR source with a high efficiency of nuclear CR production, as required for the Galactic CR sources, both in flux as well as in cutoff energy.

  17. Detection of radio emission at 610 MHz from the supernova SN2008bx in the BCD galaxy I Zw 97

    Science.gov (United States)

    Ramya, S.; Gurgubelli, U. K.; Kantharia, N. G.; Anupama, G. C.; Prabhu, T. P.

    2009-10-01

    We report the likely detection of the Type II supernova SN 2008bx (T. Puckett et. al. 2009, CBET #1348; M.C. Bentz et. al. 2009, CBET #1359; S. Blondin & P. Berlind 2009, CBET #1359) at 610 MHz in the blue compact dwarf galaxy I Zw 97. The observations of I Zw 97 were made using the Giant Meterwave Radio Telescope (GMRT) on 04 June 2009 with an on-source time of ~4.5 hours as part of the programme to study star forming regions in blue compact dwarf galaxies.

  18. SN 2009kn - the twin of the Type IIn supernova 1994W

    DEFF Research Database (Denmark)

    Kankare, E.; Ergon, M.; Bufano, F.

    2012-01-01

    on SN 2009kn offers the possibility to test these models, in the case of both SN 2009kn and SN 1994W. We associate the narrow P Cygni lines with a swept-up shell composed of circumstellar matter and SN ejecta. The broad emission line wings, seen during the plateau phase, arise from internal electron...... scattering in this shell. The slope of the light curve after the post-plateau drop is fairly consistent with that expected from the radioactive decay of 56Co, suggesting an SN origin for SN 2009kn. Assuming radioactivity to be the main source powering the light curve of SN 2009kn in the tail phase, we infer...

  19. X-ray emission from SN 2012ca: A Type Ia-CSM supernova explosion in a dense surrounding medium

    Science.gov (United States)

    Bochenek, Christopher D.; Dwarkadas, Vikram V.; Silverman, Jeffrey M.; Fox, Ori D.; Chevalier, Roger A.; Smith, Nathan; Filippenko, Alexei V.

    2018-01-01

    X-ray emission is one of the signposts of circumstellar interaction in supernovae (SNe), but until now, it has been observed only in core-collapse SNe. The level of thermal X-ray emission is a direct measure of the density of the circumstellar medium (CSM), and the absence of X-ray emission from Type Ia SNe has been interpreted as a sign of a very low density CSM. In this paper, we report late-time (500-800 d after discovery) X-ray detections of SN 2012ca in Chandra data. The presence of hydrogen in the initial spectrum led to a classification of Type Ia-CSM, ostensibly making it the first SN Ia detected with X-rays. Our analysis of the X-ray data favours an asymmetric medium, with a high-density component which supplies the X-ray emission. The data suggest a number density >108 cm-3 in the higher density medium, which is consistent with the large observed Balmer decrement if it arises from collisional excitation. This is high compared to most core-collapse SNe, but it may be consistent with densities suggested for some Type IIn or superluminous SNe. If SN 2012ca is a thermonuclear SN, the large CSM density could imply clumps in the wind, or a dense torus or disc, consistent with the single-degenerate channel. A remote possibility for a core-degenerate channel involves a white dwarf merging with the degenerate core of an asymptotic giant branch star shortly before the explosion, leading to a common envelope around the SN.

  20. Spectroscopic classification of PTSS-17zfr (SN 2017hxo) as a 91T-like type Ia supernova before the maximum

    Science.gov (United States)

    Zhang, J.-J.; Zhang, X.-L.; Wang, F. X.; Li, W.-X.; Tan, H.-J.; Li, B.; Xu, Z.-J.; Zhao, H.-B.; Wang, L.-F.; Xiang, D.-F.; Rui, L.-M.; Lin, H.

    2017-11-01

    We obtained an optical spectrum (range 350-900 nm) of PTSS-17zfr (SN 2017hxo), discovered by the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/), on UT 2017 Nov. 11.7 with the Li-Jiang 2.4 m telescope (LJT+YFOSC) at Li-Jiang Observatory of Yunnan Observatories.

  1. 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.

  2. The All-Sky Automated Survey for Supernovae (ASAS-SN) Light Curve Server v1.0

    Science.gov (United States)

    Kochanek, C. S.; Shappee, B. J.; Stanek, K. Z.; Holoien, T. W.-S.; Thompson, Todd A.; Prieto, J. L.; Dong, Subo; Shields, J. V.; Will, D.; Britt, C.; Perzanowski, D.; Pojmański, G.

    2017-10-01

    The All-Sky Automated Survey for Supernovae (ASAS-SN) is working toward imaging the entire visible sky every night to a depth of V˜ 17 mag. The present data covers the sky and spans ˜2-5 years with ˜100-400 epochs of observation. The data should contain some ˜1 million variable sources, and the ultimate goal is to have a database of these observations publicly accessible. We describe here a first step, a simple but unprecedented web interface https://asas-sn.osu.edu/ that provides an up to date aperture photometry light curve for any user-selected sky coordinate. The V band photometry is obtained using a two-pixel (16.″0) radius aperture and is calibrated against the APASS catalog. Because the light curves are produced in real time, this web tool is relatively slow and can only be used for small samples of objects. However, it also imposes no selection bias on the part of the ASAS-SN team, allowing the user to obtain a light curve for any point on the celestial sphere. We present the tool, describe its capabilities, limitations, and known issues, and provide a few illustrative examples.

  3. Defect energetics and magnetic properties of 3 d-transition-metal-doped topological crystalline insulator SnTe

    Science.gov (United States)

    Wang, Na; Wang, JianFeng; Si, Chen; Gu, Bing-Lin; Duan, WenHui

    2016-08-01

    The introduction of magnetism in SnTe-class topological crystalline insulators is a challenging subject with great importance in the quantum device applications. Based on the first-principles calculations, we have studied the defect energetics and magnetic properties of 3 d transition-metal (TM)-doped SnTe. We find that the doped TM atoms prefer to stay in the neutral states and have comparatively high formation energies, suggesting that the uniform TMdoping in SnTe with a higher concentration will be difficult unless clustering. In the dilute doping regime, all the magnetic TMatoms are in the high-spin states, indicating that the spin splitting energy of 3 d TM is stronger than the crystal splitting energy of the SnTe ligand. Importantly, Mn-doped SnTe has relatively low defect formation energy, largest local magnetic moment, and no defect levels in the bulk gap, suggesting that Mn is a promising magnetic dopant to realize the magnetic order for the theoretically-proposed large-Chern-number quantum anomalous Hall effect (QAHE) in SnTe.

  4. 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

  5. The Historical Supernovae

    OpenAIRE

    Green, D.A.; F. R. Stephenson

    2003-01-01

    The available historical records of supernovae occurring in our own Galaxy over the past two thousand years are reviewed. These accounts include the well-recorded supernovae of AD 1604 (Kepler's SN), 1572 (Tycho's SN), 1181, 1054 (which produced the Crab Nebula) and 1006, together with less certain events dating back to AD 185. In the case of the supernovae of AD 1604 and 1572 it is European records that provide the most accurate information available, whereas for earlier supernovae records a...

  6. 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.

  7. AMI-LA 15 GHz Observation of the Type IIP Supernova SN 2017eaw

    Science.gov (United States)

    Bright, Joe; Mooley, Kunal; Fender, Rob; Horesh, Assaf

    2017-05-01

    SN 2017eaw was discovered by Patrick Wiggins on 2017 May 14.24 and confirmed as a transient object (located in NGC 6946, at a distance of around 5.5 Mpc) in follow up observations from the McDonald observatory (ATel #10372).

  8. On the origin of pulsed emission from the young supernova remnant SN 1987A

    Energy Technology Data Exchange (ETDEWEB)

    Ruderman, M.; Kluzniak, W.; Shaham, J. (Columbia Univ., New York, NY (USA))

    1989-11-01

    To overcome difficulties in understanding the origin of the sub-msec optical pulses from SN 1987A, a model similar to that of Kundt and Krotscheck (1977) for pulsed synchotron emission from the Crab is applied. The interaction of the expected ultrarelativistic electron-positron pulsar wind with pulsar dipole EM wave or wind-carried toroidal magnetic field reflected from the walls of the expected pulsar cavity within the SN 1987A nebula can generate pulsed optical emission with efficiency at most 0.001. The maximum luminosity of the source is reproduced, and other observational constraints can be satisfied for an average wind energy flow of about 10 to the 38th erg/sec sr and for wind electron Lorentz factor gamma of about 100,000. This model applied to the Crab yields pulsations of much lower luminosity and frequency. 17 refs.

  9. Underpinning energetics of lithium bonding and stability in the Li-Pt-Sn system

    Science.gov (United States)

    Matar, Samir F.; Pöttgen, Rainer

    2012-10-01

    Within the Li-Pt-Sn system, we examine the electronic structures and Li-binding of LiPtSn2, Li2PtSn and Li3Pt2Sn3 with fluorite-related crystal structures. The structures with totally de-intercalated lithium keep the characteristics of the pristine ternary compound with a reduction of the volume. In Li3Pt2Sn3 the binding energies of lithium belonging to three crystallographically inequivalent Wyckoff sites are different and point to distinct activities of de-intercalation concomitant with site-selective bonding magnitudes. The derived potentials are within the range of non-oxide binary and ternary lithium based compounds and indicate the possibility of at least partial delithiation.

  10. 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

  11. An Empirical Fitting Method for Type Ia Supernova Light Curves: A Case Study of SN 2011fe

    Science.gov (United States)

    Zheng, WeiKang; Filippenko, Alexei V.

    2017-03-01

    We present a new empirical fitting method for the optical light curves of Type Ia supernovae (SNe Ia). We find that a variant broken-power-law function provides a good fit, with the simple assumption that the optical emission is approximately the blackbody emission of the expanding fireball. This function is mathematically analytic and is derived directly from the photospheric velocity evolution. When deriving the function, we assume that both the blackbody temperature and photospheric velocity are constant, but the final function is able to accommodate these changes during the fitting procedure. Applying it to the case study of SN 2011fe gives a surprisingly good fit that can describe the light curves from the first-light time to a few weeks after peak brightness, as well as over a large range of fluxes (˜5 mag, and even ˜7 mag in the g band). Since SNe Ia share similar light-curve shapes, this fitting method has the potential to fit most other SNe Ia and characterize their properties in large statistical samples such as those already gathered and in the near future as new facilities become available.

  12. Upper limits on the luminosity of the progenitor of type Ia supernova SN2014J

    DEFF Research Database (Denmark)

    Nielsen, M. T. B.; Gilfanov, M.; Bogdan, A.

    2014-01-01

    X-ray source progenitor with a photospheric radius comparable to the radius of white dwarf near the Chandrasekhar mass (~1.38 M_sun) and mass accretion rate in the interval where stable nuclear burning can occur. However, due to a relatively large hydrogen column density implied by optical......We analysed archival data of Chandra pre-explosion observations of the position of SN2014J in M82. No X-ray source at this position was detected in the data, and we calculated upper limits on the luminosities of the progenitor. These upper limits allow us to firmly rule out an unobscured supersoft...

  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. SN2015bh: NGC2770's 4th supernova or a luminous blue variable on its way to a Wolf-Rayet star?

    DEFF Research Database (Denmark)

    Thone, C. C.; de Ugarte Postigo, A.; Leloudas, G.

    2017-01-01

    shell plunging into a dense CSM. The 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 the second component with the possible SN. Since 1994 the star has been redder than an LBV in an S-Dor-like outburst. SN......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 NGC2770 in outburst over more than 20...... 2015bh lies within a spiral arm of NGC2770 next to several small star-forming regions with a metallicity of similar to 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...

  15. 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.

  16. Title: Detection of a 31.6 s pulse period for the supernova impostor SN 2010da in NGC 300, observed in ULX state

    Science.gov (United States)

    Carpano, S.; Haberl, F.; Maitra, C.

    2018-01-01

    The supernova impostor SN 2010da located in NGC 300, later identified as a likely Supergiant B[e] High-mass X-ray binary (Lau et al. 2016, ApJ, 830, 142 and Villar et al. 2016, ApJ, 830, 11), was observed in outburst during two long (139 and 82 ks) XMM-Newton observations performed on 2016 December 17 to 20. We report the discovery of a strong periodic modulation in the X-ray flux with a pulse period of 31.6 s and a very rapid spin-up, and confirm therefore that the compact object is a neutron star.

  17. Particle acceleration and production of energetic photons in SN1987A

    Science.gov (United States)

    Gaisser, T. K.; Stanev, Todor; Harding, Alice

    1987-01-01

    A pulsar wind model for the acceleration of particles in SN1987A is discussed. The expected photon flux is investigated in terms of the spectrum of parent protons and electrons, the nature of the region in which they propagate after acceleration, and the magnetic field and radiation environment which determines the subsequent fate of produced photons. The model is found to produce observable signals if the spin period of the pulsar is 10 ms or less.

  18. Predicting the Presence of Companions for Stripped-envelope Supernovae: The Case of the Broad-lined Type Ic SN 2002ap

    Science.gov (United States)

    Zapartas, E.; de Mink, S. E.; Van Dyk, S. D.; Fox, O. D.; Smith, N.; Bostroem, K. A.; de Koter, A.; Filippenko, A. V.; Izzard, R. G.; Kelly, P. L.; Neijssel, C. J.; Renzo, M.; Ryder, S.

    2017-06-01

    Many young, massive stars are found in close binaries. Using population synthesis simulations we predict the likelihood of a companion star being present when these massive stars end their lives as core-collapse supernovae (SNe). We focus on stripped-envelope SNe, whose progenitors have lost their outer hydrogen and possibly helium layers before explosion. We use these results to interpret new Hubble Space Telescope observations of the site of the broad-lined Type Ic SN 2002ap, 14 years post-explosion. For a subsolar metallicity consistent with SN 2002ap, we expect a main-sequence (MS) companion present in about two thirds of all stripped-envelope SNe and a compact companion (likely a stripped helium star or a white dwarf/neutron star/black hole) in about 5% of cases. About a quarter of progenitors are single at explosion (originating from initially single stars, mergers, or disrupted systems). All of the latter scenarios require a massive progenitor, inconsistent with earlier studies of SN 2002ap. Our new, deeper upper limits exclude the presence of an MS companion star >8-10 {M}⊙ , ruling out about 40% of all stripped-envelope SN channels. The most likely scenario for SN 2002ap includes nonconservative binary interaction of a primary star initially ≲ 23 {M}⊙ . Although unlikely (<1% of the scenarios), we also discuss the possibility of an exotic reverse merger channel for broad-lined Type Ic events. Finally, we explore how our results depend on the metallicity and the model assumptions and discuss how additional searches for companions can constrain the physics that govern the evolution of SN progenitors.

  19. LSQ14efd: observations of the cooling of a shock break-out event in a type Ic Supernova

    Science.gov (United States)

    Barbarino, C.; Botticella, M. T.; Dall'Ora, M.; Della Valle, M.; Benetti, S.; Lyman, J. D.; Smartt, S. J.; Arcavi, I.; Baltay, C.; Bersier, D.; Dennefeld, M.; Ellman, N.; Fraser, M.; Gal-Yam, A.; Hosseinzadeh, G.; Howell, D. A.; Inserra, C.; Kankare, E.; Leloudas, G.; Maguire, K.; McCully, C.; Mitra, A.; McKinnon, R.; Olivares E., F.; Pignata, G.; Rabinowitz, D.; Rostami, S.; Smith, K. W.; Sullivan, M.; Valenti, S.; Yaron, O.; Young, D.

    2017-10-01

    We present the photometric and spectroscopic evolution of the type Ic supernova LSQ14efd, discovered by the La Silla QUEST survey and followed by PESSTO. LSQ14efd was discovered few days after explosion and the observations cover up to ∼100 d. The early photometric points show the signature of the cooling of the shock break-out event experienced by the progenitor at the time of the supernova explosion, one of the first for a type Ic supernova. A comparison with type Ic supernova spectra shows that LSQ14efd is quite similar to the type Ic SN 2004aw. These two supernovae have kinetic energies that are intermediate between standard Ic explosions and those which are the most energetic explosions known (e.g. SN 1998bw). We computed an analytical model for the light-curve peak and estimated the mass of the ejecta 6.3 ± 0.5 M⊙, a synthesized nickel mass of 0.25 M⊙ and a kinetic energy of Ekin = 5.6 ± 0.5 × 1051 erg. No connection between LSQ14efd and a gamma-ray burst event could be established. However we point out that the supernova shows some spectroscopic similarities with the peculiar SN-Ia 1999ac and the SN-Iax SN 2008A. A core-collapse origin is most probable considering the spectroscopic, photometric evolution and the detection of the cooling of the shock breakout.

  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. Type Ia Supernova Properties as a Function of the Distance to the Host Galaxy in the SDSS-II SN Survey

    Energy Technology Data Exchange (ETDEWEB)

    Galbany, Lluis [Institut de Fisica d' Altes Energies (IFAE), Barcelona (Spain); et al.

    2012-08-20

    We use type-Ia supernovae (SNe Ia) discovered by the SDSS-II SN Survey to search for dependencies between SN Ia properties and the projected distance to the host galaxy center, using the distance as a proxy for local galaxy properties (local star-formation rate, local metallicity, etc.). The sample consists of almost 200 spectroscopically or photometrically confirmed SNe Ia at redshifts below 0.25. The sample is split into two groups depending on the morphology of the host galaxy. We fit light-curves using both MLCS2k2 and SALT2, and determine color (AV, c) and light-curve shape (delta, x1) parameters for each SN Ia, as well as its residual in the Hubble diagram. We then correlate these parameters with both the physical and the normalized distances to the center of the host galaxy and look for trends in the mean values and scatters of these parameters with increasing distance. The most significant (at the 4-sigma level) finding is that the average fitted AV from MLCS2k2 and c from SALT2 decrease with the projected distance for SNe Ia in spiral galaxies. We also find indications that SNe in elliptical galaxies tend to have narrower light-curves if they explode at larger distances, although this may be due to selection effects in our sample. We do not find strong correlations between the residuals of the distance moduli with respect to the Hubble flow and the galactocentric distances, which indicates a limited correlation between SN magnitudes after standardization and local host metallicity.

  3. Nurseries of Supernovae

    DEFF Research Database (Denmark)

    Frederiksen, Teddy

    Type Ia supernovae (SNe) have long been the gold standard for precision cosmology and after several decades of intense research the supernova (SN) community was in 2011 honored by giving the Nobel Prize in physics for the discovery of Dark Energy to the leaders of the two big SN collaborations...... compared to most low redshift (z 1) redshift SNe. This is mainly due to the change in specific star-formation rate as a function of redshift. This can potentially impact the use of high redshift SN Ia as standard candels...

  4. Nurseries of Supernovae

    DEFF Research Database (Denmark)

    Frederiksen, Teddy

    Type Ia supernovae (SNe) have long been the gold standard for precision cosmology and after several decades of intense research the supernova (SN) community was in 2011 honored by giving the Nobel Prize in physics for the discovery of Dark Energy to the leaders of the two big SN collaborations...... mechanisms that governs the SN explosions. In the first of three papers I investigate the host galaxy of the first SN Ia found in the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) SN search. From long slit spectroscopy using the Xshooter spectrograph and broadband photometry I determine...... the gasphase metallicity, stellar mass and stellar age for this z = 1.55 host galaxy. I am also able to rule out the presence of any AGN though emission-line ratios. The host is classified as a highly star forming, low mass, low metallicity galaxy. It is a clear outlier in star formation and stellar mass...

  5. Interpretation of the historic Yemeni reports of supernova SN 1006: early discovery in mid-April 1006 ?

    CERN Document Server

    Neuhaeuser, Ralph; Rada, Wafiq; Chapman, Jesse; Luge, Daniela; Kunitzsch, Paul

    2016-01-01

    The recently published Yemeni observing report about SN 1006 from al-Yamani clearly gives AD 1006 Apr $17 \\pm 2$ (mid-Rajab 396h) as first observation date. Since this is about 1.5 weeks earlier than the otherwise earliest reports (Apr 28 or 30) as discussed so far, we were motivated to investigate an early sighting in more depth. We searched for additional evidences from other areas like East Asia and Europe. We found that the date given by al-Yamani is fully consistent with other evidence, including: (a) SN 1006 "rose several times half an hour after sunset" (al-Yamani), which is correct for the location of Sana in Yemen for the time around Apr 17, but it would not be correct for late Apr or early May; (b) the date (3rd year, 3rd lunar month, 28th day wuzi, Ichidai Yoki) for an observation of a guest star in Japan is inconsistent (there is no day wuzi in that lunar month), but may be dated to Apr 16 by reading wuwu date rather than a wuzi date; (c) there is observational evidence that SN 1006 was observed i...

  6. Bi-polar Supernova Explosions

    OpenAIRE

    Wang, Lifan; Howell, D. Andrew; Hoeflich, Peter; Wheeler, J. Craig

    1999-01-01

    We discuss the optical spectropolarimetry of several core-collapse supernovae, SN 1996cb (Type IIB), SN 1997X (Type Ic), and SN 1998S (Type IIn). The data show polarization evolution of several spectral features at levels from 0.5% to above 4%. The observed line polarization is intrinsic to the supernovae and not of interstellar origin. These data suggest that the the distribution of ejected matter is highly aspherical. In the case of SN 1998S, the minimum major to minor axis ratio must be la...

  7. Discovery of the Broad-lined Type Ic SN 2013cq Associated with the Very Energetic GRB 130427A

    NARCIS (Netherlands)

    Xu, D.; de Ugarte Postigo, A.; Leloudas, G.; Krühler, T.; Cano, Z.; Hjorth, J.; Malesani, D.; Fynbo, J.P.U.; Thöne, C.C.; Sánchez-Ramírez, R.; Schulze, S.; Jakobsson, P.; Kaper, L.; Sollerman, J.; Watson, D.J.; Cabrera-Lavers, A.; Cao, C.; Covino, S.; Flores, H.; Geier, S.; Gorosabel, J.; Hu, S.M.; Milvang-Jensen, B.; Sparre, M.; Xin, L.P.; Zhang, T.M.; Zheng, W.K.; Zou, Y.C.

    2013-01-01

    Long-duration gamma-ray bursts (GRBs) at z < 1 are found in most cases to be accompanied by bright, broad-lined Type Ic supernovae (SNe Ic-BL). The highest-energy GRBs are mostly located at higher redshifts, where the associated SNe are hard to detect observationally. Here, we present early and late

  8. Supernova 2008J

    DEFF Research Database (Denmark)

    Tadddia, F.; Stritzinger, Maximilian David; 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 Supernova...... Project are studied and compared to those of SNe 2002ic and 2005gj. Our NIR spectrum is the first obtained for a 2002ic-like object extending up to 2.2 μm. A published high-resolution spectrum is used to provide insight on the circumstellar material (CSM). Results: SN 2008J is found to be affected by AV...... ~ 1.9 mag of extinction and to closely resemble SN 2002ic. Spectral and color comparison to SNe 2002ic and 2005gj suggests RV J is as luminous as SN 2005gj (Vmax = -20.3 mag), we conclude...

  9. Nearby supernova host galaxies from the CALIFA survey. II. Supernova environmental metallicity

    NARCIS (Netherlands)

    Galbany, L.; Stanishev, V.; Mourão, A. M.; Rodrigues, M.; Flores, H.; Walcher, C. J.; Sánchez, S. F.; García-Benito, R.; Mast, D.; Badenes, C.; González Delgado, R. M.; 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 progenitor, together with its mass, is one of the main parameters that can rule the progenitor's fate. We present the second study of nearby supernova (SN) host galaxies (0.005 ⊙) > 10 dex) by targeted searches. We neither found evidence that the metallicity at the SN

  10. Supernovae and cosmic rays

    CERN Document Server

    Woltjer, L

    1978-01-01

    The energetic requirements for cosmic-ray acceleration are evaluated and the abundances of various elements, electrons, and positrons, are reviewed. Various models for cosmic-ray production involving different aspects of the supernova process are evaluated. The difficulties in theories which make pulsars the main source of cosmic rays are stressed. (4 refs).

  11. NASA's Chandra Sees Brightest Supernova Ever

    Science.gov (United States)

    2007-05-01

    WASHINGTON - The brightest stellar explosion ever recorded may be a long-sought new type of supernova, according to observations by NASA's Chandra X-ray Observatory and ground-based optical telescopes. This discovery indicates that violent explosions of extremely massive stars were relatively common in the early universe, and that a similar explosion may be ready to go off in our own galaxy. "This was a truly monstrous explosion, a hundred times more energetic than a typical supernova," said Nathan Smith of the University of California at Berkeley, who led a team of astronomers from California and the University of Texas in Austin. "That means the star that exploded might have been as massive as a star can get, about 150 times that of our sun. We've never seen that before." Chandra X-ray Image of SN 2006gy Chandra X-ray Image of SN 2006gy Astronomers think many of the first generation of stars were this massive, and this new supernova may thus provide a rare glimpse of how the first stars died. It is unprecedented, however, to find such a massive star and witness its death. The discovery of the supernova, known as SN 2006gy, provides evidence that the death of such massive stars is fundamentally different from theoretical predictions. "Of all exploding stars ever observed, this was the king," said Alex Filippenko, leader of the ground-based observations at the Lick Observatory at Mt. Hamilton, Calif., and the Keck Observatory in Mauna Kea, Hawaii. "We were astonished to see how bright it got, and how long it lasted." The Chandra observation allowed the team to rule out the most likely alternative explanation for the supernova: that a white dwarf star with a mass only slightly higher than the sun exploded into a dense, hydrogen-rich environment. In that event, SN 2006gy should have been 1,000 times brighter in X-rays than what Chandra detected. Animation of SN 2006gy Animation of SN 2006gy "This provides strong evidence that SN 2006gy was, in fact, the death of an

  12. STRESS Counting Supernovae

    Science.gov (United States)

    Botticella, M. T.; Cappellaro, E.; Riello, M.; Greggio, L.; Benetti, S.; Patat, F.; Turatto, M.; Altavilla, G.; Pastorello, A.; Valenti, S.; Zampieri, L.; Harutyunyan, A.; Pignata, G.; Taubenberger, S.

    2008-12-01

    The rate of occurrence of supernovae (SNe) is linked to some of the basic ingredients of galaxy evolution, such as the star formation rate, the chemical enrichment and feedback processes. SN rates at intermediate redshift and their dependence on specific galaxy properties have been investigated in the Southern inTermediate Redshift ESO Supernova Search (STRESS). The rate of core collapse SNe (CC SNe) at a redshift of around 0.25 is found to be a factor two higher than the local value, whereas the SNe Ia rate remains almost constant. SN rates in red and blue galaxies were also measured and it was found that the SNe Ia rate seems to be constant in galaxies of different colour, whereas the CC SN rate seems to peak in blue galaxies, as in the local Universe.

  13. Supernovae Discovery Efficiency

    Science.gov (United States)

    John, Colin

    2018-01-01

    Abstract:We present supernovae (SN) search efficiency measurements for recent Hubble Space Telescope (HST) surveys. Efficiency is a key component to any search, and is important parameter as a correction factor for SN rates. To achieve an accurate value for efficiency, many supernovae need to be discoverable in surveys. This cannot be achieved from real SN only, due to their scarcity, so fake SN are planted. These fake supernovae—with a goal of realism in mind—yield an understanding of efficiency based on position related to other celestial objects, and brightness. To improve realism, we built a more accurate model of supernovae using a point-spread function. The next improvement to realism is planting these objects close to galaxies and of various parameters of brightness, magnitude, local galactic brightness and redshift. Once these are planted, a very accurate SN is visible and discoverable by the searcher. It is very important to find factors that affect this discovery efficiency. Exploring the factors that effect detection yields a more accurate correction factor. Further inquires into efficiency give us a better understanding of image processing, searching techniques and survey strategies, and result in an overall higher likelihood to find these events in future surveys with Hubble, James Webb, and WFIRST telescopes. After efficiency is discovered and refined with many unique surveys, it factors into measurements of SN rates versus redshift. By comparing SN rates vs redshift against the star formation rate we can test models to determine how long star systems take from the point of inception to explosion (delay time distribution). This delay time distribution is compared to SN progenitors models to get an accurate idea of what these stars were like before their deaths.

  14. Study of supernovae important for cosmology

    Science.gov (United States)

    Baklanov, P. V.; Blinnikov, S. I.; Potashov, M. Sh.; Dolgov, A. D.

    2013-12-01

    The dense shell method for the determination of distances to type-IIn supernovae has been briefly reviewed. Applying our method to SN 2006gy, SN 2009ip, and SN 2010jl supernovae, we have obtained distances in excellent agreement with the previously known distances to the parent galaxies. The dense shell method is based on the radiation hydrodynamic model of a supernova. The method of the blackbody model, as well as the correctness of its application for simple estimates of distances from observation data, has been justified.

  15. 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...

  16. Infrared opportunities for supernova 1987A

    Science.gov (United States)

    Dwek, Eli

    1988-01-01

    IR observations of SN 1987A are reviewed, focusing on the IR processes in the supernova. IR line emission, IR emission from supernova condensates, IR echoes, IR emission from shock-heated dust, and IR emission from a cometary cloud are examined. A list is given of IR studies of SN 1987A and the characteristics of the instruments used in these studies. Preliminary results from several IR studies are considered.

  17. A relativistic type Ibc supernova without a detected gamma-ray burst.

    Science.gov (United States)

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

    2010-01-28

    Long duration gamma-ray bursts (GRBs) mark the explosive death of some massive stars and are a rare sub-class of type Ibc supernovae. They are distinguished by the production of an energetic and collimated relativistic outflow powered by a central engine (an accreting black hole or neutron star). Observationally, this outflow is manifested in the pulse of gamma-rays and a long-lived radio afterglow. Until now, central-engine-driven supernovae have been discovered exclusively through their gamma-ray emission, yet it is expected that a larger population goes undetected because of limited satellite sensitivity or beaming of the collimated emission away from our line of sight. In this framework, the recovery of undetected GRBs may be possible through radio searches for type Ibc supernovae with relativistic outflows. Here we report the discovery of luminous radio emission from the seemingly ordinary type Ibc SN 2009bb, which requires a substantial relativistic outflow powered by a central engine. A comparison with our radio survey of type Ibc supernovae reveals that the fraction harbouring central engines is low, about one per cent, measured independently from, but consistent with, the inferred rate of nearby GRBs. Independently, a second mildly relativistic supernova has been reported.

  18. Predicting the Presence of Companions for Stripped-envelope Supernovae : The Case of the Broad-lined Type Ic SN 2002ap

    NARCIS (Netherlands)

    Zapartas, E.; de Mink, S.E.; Van Dyk, S.D.; Fox, O.D.; Smith, N.; Bostroem, K.A.; de Koter, A.; Filippenko, A.V.; Izzard, R.G.; Kelly, P.L.; Neijssel, C.J.; Renzo, M.; Ryder, S.

    2017-01-01

    Many young, massive stars are found in close binaries. Using population synthesis simulations we predict the likelihood of a companion star being present when these massive stars end their lives as core-collapse supernovae (SNe). We focus on stripped-envelope SNe, whose progenitors have lost their

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-08-01

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

  20. A Deep Search with the Hubble Space Telescope for Late-Time Supernova Signatures in the Hosts of XRF 011030 and XRF 020427

    Science.gov (United States)

    Levan, Andrew; Patel, Sandeep; Kouveliotou, Chryssa; Fruchter, Andrew; Rhoads, James; Rol, Evert; Ramirez-Ruiz, Enrico; Gorosabel, Javier; Hiorth, Jens; Wijers, Ralph

    2005-01-01

    X-ray flashes (XRFs) are, like gamma-ray bursts (GRBs), thought to signal the collapse of massive stars in distant galaxies. Many models posit that the isotropic equivalent energies of XRFs are lower than those for GRBs, such that they are visible fiom a reduced range of distances when compared with GRBs. Here we present the results of two-epoch Hubble Space Telescope imaging of two XRFs. These images, taken approximately 45 and 200 days postburst, reveal no evidence of an associated supernova in either case. Supernovae such as SN 1998bw would have been visible out to z approximately 1.5 in each case, while fainter supernovae such as SN 2002ap would have been visible to z approximately 1. If the XRFs lie at such large distances, their energies would not fit the observed correlation between the GRB peak energy and isotropic energy release (E(sub p) proportional to E(sub iso)(sup 1/2), in which soft bursts are less energetic. We conclude that, should these XRFs reside at low redshifts (z less than 0.6), either their line of sight is heavily extinguished, they are associated with extremely faint supernovae, or, unlike GRBs, these XRFs do not have temporally coincident supernovae.

  1. The likelihood for supernova neutrino analyses

    CERN Document Server

    Ianni, A; Strumia, A; Torres, F R; Villante, F L; Vissani, F

    2009-01-01

    We derive the event-by-event likelihood that allows to extract the complete information contained in the energy, time and direction of supernova neutrinos, and specify it in the case of SN1987A data. We resolve discrepancies in the previous literature, numerically relevant already in the concrete case of SN1987A data.

  2. Modelling the interaction of thermonuclear supernova remnants with circumstellar structures: the case of Tycho's supernova remnant

    NARCIS (Netherlands)

    Chiotellis, A.; Kosenko, D.; Schure, K.M.; Vink, J.; Kaastra, J.S.

    2013-01-01

    The well-established Type Ia remnant of Tycho's supernova (SN 1572) reveals discrepant ambient medium-density estimates based on either the measured dynamics or the X-ray emission properties. This discrepancy can potentially be solved by assuming that the supernova remnant (SNR) shock initially

  3. Supernova studies in the SDSS-II/SNe survey spectroscopy of the peculiar SN 2007qd, and photometric properties of Type-Ia supernovae as a function of the distance to the host galaxy /

    OpenAIRE

    Galbany i Gonzàlez, Lluís

    2012-01-01

    Descripció del recurs: el 01 setembre 2012 Aquesta tesi engloba el treball fet durant els ultims quatre anys com a estudiant de doctorat a l'Institut de Física d'Altes Energies (IFAE), emmarcat dins de la col·labaració Sloan Digital Sky Survey II Supernova (SDSS-II/SNe) Survey. Al primer capítol (§1) s'introdueixen els principals conceptes del Model Estàndar de Cosmologia, presentant els seus orígens, les propietats dels seus continguts, i les mesures de distància i brillantor. També es re...

  4. Superluminous Supernovae in the Dark Energy Survey

    Science.gov (United States)

    D'Andrea, Christopher; Smith, Mathew; Sullivan, Mark; Nichol, Bob; Pan, Yen-Chen; Thomas, Ben; Prajs, Szymon; Angus, Charlotte; Dark Energy Survey

    2018-01-01

    The Dark Energy Survey Supernova Program (DES-SN) has begun its fifth and final season of operations. With a six-day cadence over 27 deg2 in each 6-month observing season and griz depths of 23.5-24.5 mag (AB), DES-SN presents an impressive data set for obtaining high-quality superluminous supernova (SLSN) light curves. I present highlights of the discoveries of DES SLSNe to date. These include at least 18 spectroscopically-classified SLSNe over a redshift range 0.2 2 SLSNe which should be well above the limiting magnitude of the DES-SN data.

  5. 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...

  6. Smoking Supernovae

    OpenAIRE

    Gomez, Haley Louise; Eales, Stephen Anthony; Dunne, L.

    2007-01-01

    The question ‘Are supernovae important sources of dust?’ is a contentious one. Observations with the Infrared Astronomical Satellite (IRAS) and the Infrared Space Observatory (ISO) only detected very small amounts of hot dust in supernova remnants. Here, we review observations of two young Galactic remnants with the Submillimetre Common User Bolometer Array (SCUBA), which imply that large quantities of dust are produced by supernovae. The association of dust with the Cassiopeia A remnant is i...

  7. CSI in Supernova Remnants

    Science.gov (United States)

    Chu, You-Hua

    2017-02-01

    Supernovae (SNe) explode in environments that have been significantly modified by the SN progenitors. For core-collapse SNe, the massive progenitors ionize the ambient interstellar medium (ISM) via UV radiation and sweep the ambient ISM via fast stellar winds during the main sequence phase, replenish the surroundings with stellar material via slow winds during the luminous blue variable (LBV) or red supergiant (RSG) phase, and sweep up the circumstellar medium (CSM) via fast winds during the Wolf-Rayet (WR) phase. If a massive progenitor was in a close binary system, the binary interaction could have caused mass ejection in certain preferred directions, such as the orbital plane, and even bipolar outflow/jet. As a massive star finally explodes, the SN ejecta interacts first with the CSM that was ejected and shaped by the star itself. As the newly formed supernova remnant (SNR) expands further, it encounters interstellar structures that were shaped by the progenitor from earlier times. Therefore, the structure and evolution of a SNR is largely dependent on the initial mass and close binarity of the SN progenitor. The Large Magellanic Cloud (LMC) has an excellent sample of over 50 confirmed SNRs that are well resolved by Hubble Space Telescope, Chandra X-ray Observatory, and Spitzer Space Telescope. These multi-wavelength observations allow us to conduct stellar forensics in SNRs and understand the wide variety of morphologies and physical properties of SNRs observed.

  8. Ultra-high-energy cosmic ray acceleration in engine-driven relativistic supernovae.

    Science.gov (United States)

    Chakraborti, S; Ray, A; Soderberg, A M; Loeb, A; Chandra, P

    2011-02-01

    The origin of ultra-high-energy cosmic rays (UHECRs) remains an enigma. They offer a window to new physics, including tests of physical laws at energies unattainable by terrestrial accelerators. They must be accelerated locally, otherwise, background radiations would severely suppress the flux of protons and nuclei, at energies above the Greisen-Zatsepin-Kuzmin (GZK) limit. Nearby, gamma ray bursts (GRBs), hypernovae, active galactic nuclei and their flares have all been suggested and debated as possible sources. A local sub-population of type Ibc supernovae (SNe) with mildly relativistic outflows have been detected as sub-energetic GRBs, X-ray flashes and recently as radio afterglows without detected GRB counterparts. Here, we measure the size-magnetic field evolution, baryon loading and energetics, using the observed radio spectra of SN 2009bb. We place such engine-driven SNe above the Hillas line and establish that they can readily explain the post-GZK UHECRs.

  9. 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.

  10. The supernova cosmology cookbook: Bayesian numerical recipes

    OpenAIRE

    Karpenka, Natallia V.

    2014-01-01

    Theoretical and observational cosmology have enjoyed a number of significant successes over the last two decades. Cosmic microwave background measurements from the Wilkinson Microwave Anisotropy Probe and Planck, together with large-scale structure and supernova (SN) searches, have put very tight constraints on cosmological parameters. Type Ia supernovae (SNIa) played a central role in the discovery of the accelerated expansion of the Universe, recognised by the Nobel Prize in Physics in 2011...

  11. Rates and progenitors of type Ia supernovae

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-01-01

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

  12. Supernova forecast with strong lensing

    Science.gov (United States)

    Suwa, Yudai

    2018-02-01

    In the coming Large Synoptic Survey Telescope era, we will observe O(100) of lensed supernovae (SNe). In this paper, we investigate the possibility for predicting time and sky position of an SN using strong lensing. We find that it will be possible to predict the time and position of the fourth image of SNe which produce four images by strong lensing, with combined information from the three previous images. It is useful to perform multimessenger observations of the very early phase of SN explosions including the shock breakout.

  13. Physics of Supernovae

    Science.gov (United States)

    Nadyozhin, D. K.; Imshennik, V. S.

    The origin of cosmic rays (CR) is supposed to be closely connected with supernovae (SNe) which create the conditions favorable for various mechanisms of the CR acceleration to operate effectively. First, modern ideas about the physics of the SN explosion are briefly discussed: the explosive thermonuclear burning in degenerate white dwarfs resulting in Type Ia SNe and the gravitational collapse of stellar cores giving rise to other types of SNe (Ib, Ic, IIL, IIP). Next, we survey some global properties of the SNe of different types: the total explosion energy distribution of various components (kinetic energy of the hydrodynamic flow, electromagnetic radiation, temporal behavior of the neutrino emission and individual energies of different neutrino flavors). Then, we discuss in the possibility of direct hydrodynamic acceleration by the shock wave breakout and the properties of the SN shocks in the circumstellar medium. Then the properties of the neutrino radiation from the core-collapse SNe and a possibility to incorporate both the LSD Mont Blanc neutrino event and that recorded by the K II and IMB detectors into a single scenario are described in detail. Finally, the issues of the neutrino nucleosynthesis and of the connection between supernova and gamma-ray bursts are discussed.

  14. A statistical analysis of angular distribution of neutrino events observed in Kamiokande II and IMB detectors from supernova SN 1987 A

    Energy Technology Data Exchange (ETDEWEB)

    Krivoruchenko, M.I. (Institut Teoreticheskoj i Ehksperimental' noj Fiziki, Moscow (USSR))

    1989-11-01

    A detailed statistical analysis of angular distribution of neutrino events observed in Kamiokande II and IMB detectors on UT 07:35, 2/23'87 is carried out. Distribution functions of the mean scattering angles in the reaction anti 4u{sub e}p->e{sup +}n and 4ue->4ue are constructed with account taken of the multiple Coulomb scattering and the experimental angular errors. The Smirnov and Wald-Wolfowitz run tests are used to test the hypothesis that the angular distributions of events from the two detectors agree with each other. We test with the use of the Kolmogorov and Mises statistical criterions the hypothesis that the recorded events all represent anti 4u{sub e}p->e{sup +}n inelastic scatterings. Then the Neyman-Pearson test is applied to each event in testing the hypothesis anti 4u{sub e}p->e{sup +}n against the alternative 4ue->4ue. The hypotheses that the number of elastic events equals s=0, 1, 2, ... against the alternatives snot =0, 1, 2, ... are tested on the basis of the generalized likelihood ratio criterion. The confidence intervals for the number of elastic events are also constructed. The current supernova models fail to give a satisfactory account of the angular distribution data. (orig.).

  15. Supernova 1987A at 29 years

    Science.gov (United States)

    McCray, Richard

    2016-06-01

    In the 29 years since it was discovered, SN 1987A has evolved from supernova to supernova remnant, in the sense that its luminosity is now dominated by radiation from its shock interaction with circumstellar matter rather than radioactive decay of newly synthesized elements. The circumstellar matter has a complex structure and the impact of the supernova debris results in a complex distribution of shocks, with velocities ranging from a few hundred to several thousand km/s. The supernova blast wave is overtaking dense knots in the equatorial ring, resulting in rapidly brightening optical “hotspots”, while the interaction with less dense matter gives rise to X-rays. The X-rays illuminate the outer supernova debris, causing it to glow at optical wavelengths. The ALMA telescope provides a new window at mm/sub-mm wavelengths, enabling us to probe the structure of the cold inner debris through molecular emission lines.

  16. EXITE/IPC observations of SN1987A and southern targets

    Science.gov (United States)

    Grindlay, Jonathan E.

    1991-01-01

    The Energetic X-ray Imaging Telescope Experiment (EXITE) was developed to a flight-ready status and conducted two flights (May 18, 1988, and May 8-10, 1989) from Alice Springs, Australia, as part of the campaigns to observe the supernova SN1987A. The basic operation of the detector and gondola systems in the laboratory was tested on the first flight and found to meet expected performance values. A bizarre 'balloon tape' insulation problem, however, prevented normal telescope pointing on the first flight so no data on SN1987A or other targets were obtained. Following a successful second EXITE flight from Ft. Sumner, NM, in October 1988, the experiment was flown again on a successful 30 hour flight as part of the final 1989 supernova campaign. A second x-ray imaging experiment from MSFC was also flown (piggy-back) for this third flight. Good data were obtained on the supernova and a variety of high priority galactic targets, and final analysis is still in progress. Preliminary results from this flight are presented.

  17. Supernova 1604, Kepler's supernova, and its remnant

    OpenAIRE

    Vink, Jacco

    2016-01-01

    Supernova 1604 is the last Galactic supernova for which historical records exist. Johannes Kepler's name is attached to it, as he published a detailed account of the observations made by himself and European colleagues. Supernova 1604 was very likely a Type Ia supernova, which exploded 350 pc to 750 pc above the Galactic plane. Its supernova remnant, known as Kepler's supernova remnant, shows clear evidence for interaction with nitrogen-rich material in the north/northwest part of the remnant...

  18. 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

  19. THE DETECTION OF A SN IIn IN OPTICAL FOLLOW-UP OBSERVATIONS OF ICECUBE NEUTRINO EVENTS

    Energy Technology Data Exchange (ETDEWEB)

    Aartsen, M. G.; Abraham, K.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Ahrens, M.; Altmann, D.; Anderson, T.; Archinger, M.; Arguelles, C.; Arlen, T. C.; Auffenberg, J.; Bai, X.; Barwick, S. W.; Baum, V.; Bay, R.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H. [Astrophysics Research Centre, School of Mathematics and Physics, Queen' s University Belfast, Belfast, BT7 1NN (United Kingdom); Collaboration: IceCube Collaboration; for the PTF Collaboration; for the Swift Collaboration; for the Pan-STARRS1 Science Consortium; and others

    2015-09-20

    The IceCube neutrino observatory pursues a follow-up program selecting interesting neutrino events in real-time and issuing alerts for electromagnetic follow-up observations. In 2012 March, the most significant neutrino alert during the first three years of operation was issued by IceCube. In the follow-up observations performed by the Palomar Transient Factory (PTF), a Type IIn supernova (SN IIn) PTF12csy was found 0.°2 away from the neutrino alert direction, with an error radius of 0.°54. It has a redshift of z = 0.0684, corresponding to a luminosity distance of about 300 Mpc and the Pan-STARRS1 survey shows that its explosion time was at least 158 days (in host galaxy rest frame) before the neutrino alert, so that a causal connection is unlikely. The a posteriori significance of the chance detection of both the neutrinos and the SN at any epoch is 2.2σ within IceCube's 2011/12 data acquisition season. Also, a complementary neutrino analysis reveals no long-term signal over the course of one year. Therefore, we consider the SN detection coincidental and the neutrinos uncorrelated to the SN. However, the SN is unusual and interesting by itself: it is luminous and energetic, bearing strong resemblance to the SN IIn 2010jl, and shows signs of interaction of the SN ejecta with a dense circumstellar medium. High-energy neutrino emission is expected in models of diffusive shock acceleration, but at a low, non-detectable level for this specific SN. In this paper, we describe the SN PTF12csy and present both the neutrino and electromagnetic data, as well as their analysis.

  20. The supernova - supernova remnant connection through multi-dimensional magnetohydrodynamic modeling

    Science.gov (United States)

    Orlando, S.; Miceli, M.; Petruk, O.; Ono, M.

    2017-10-01

    Supernova remnants (SNRs) are diffuse extended sources often characterized by a rather complex morphology and a highly non-uniform distribution of ejecta. General consensus is that such a morphology reflects, on one hand, pristine structures and features of the progenitor supernova (SN) explosion and, on the other hand, the early interaction of the SN blast wave with the inhomogeneous circumstellar medium (CSM) formed in the latest stages of the progenitor star's evolution. Deciphering X-ray observations of SNRs, therefore, might open the possibility to reconstruct the ejecta structure as it was soon after the SN explosion and the structure and geometry of the medium immediately surrounding the progenitor star. This requires accurate and detailed models which describe the evolution from the on-set of the SN to the full remnant development and which connect the X-ray emission properties of the remnants to the progenitor SNe. Here we show how multi-dimensional SN-SNR magnetohydrodynamic models have been very effective in deciphering X-ray observations of SNR Cassiopeia A and SN 1987A. This has allowed us to unveil the average structure of ejecta in the immediate aftermath of the SN explosion and to constrain the 3D pre-supernova structure and geometry of the environment surrounding the progenitor SN.

  1. Modeling Type IIn Supernova Light Curves

    Science.gov (United States)

    De La Rosa, Janie; Roming, Peter; Fryer, Chris

    2016-01-01

    We present near-by Type IIn supernovae observed with Swift's Ultraviolet/Optical Telescope (UVOT). Based on the diversity of optical light curve properties, this Type II subclass is commonly referred to as heterogeneous. At the time of discovery, our IIn sample is ~ 2 magnitudes brighter at ultraviolet wavelengths than at optical wavelengths, and ultraviolet brightness decays faster than the optical brightness. We use a semi-analytical supernova (SN) model to better understand our IIn observations, and focus on matching specific observed light curves features, i.e peak luminosity and decay rate. The SN models are used to study the effects of initial SN conditions on early light curves, and to show the extent of the "uniqueness" problem in SN light curves. We gratefully acknowledge the contributions from members of the Swift UVOT team, the NASA astrophysics archival data analysis program, and the NASA Swift guest investigator program.

  2. Supernova 2010ev: A reddened high velocity gradient type Ia supernova

    Science.gov (United States)

    Gutiérrez, Claudia P.; González-Gaitán, Santiago; Folatelli, Gastón; Pignata, Giuliano; Anderson, Joseph P.; Hamuy, Mario; Morrell, Nidia; Stritzinger, Maximilian; Taubenberger, Stefan; Bufano, Filomena; Olivares E., Felipe; Haislip, Joshua B.; Reichart, Daniel E.

    2016-05-01

    Aims: We present and study the spectroscopic and photometric evolution of the type Ia supernova (SN Ia) 2010ev. Methods: We obtain and analyze multiband optical light curves and optical/near-infrared spectroscopy at low and medium resolution spanning -7 days to +300 days from the B-band maximum. Results: A photometric analysis shows that SN 2010ev is a SN Ia of normal brightness with a light-curve shape of Δm15(B) = 1.12 ± 0.02 and a stretch s = 0.94 ± 0.01 suffering significant reddening. From photometric and spectroscopic analysis, we deduce a color excess of E(B - V) = 0.25 ± 0.05 and a reddening law of Rv = 1.54 ± 0.65. Spectroscopically, SN 2010ev belongs to the broad-line SN Ia group, showing stronger than average Si IIλ6355 absorption features. We also find that SN 2010ev is a high velocity gradient SN with v˙Si = 164 ± 7 km s-1 d-1. The photometric and spectral comparison with other supernovae shows that SN 2010ev has similar colors and velocities to SN 2002bo and SN 2002dj. The analysis of the nebular spectra indicates that the [Fe II]λ7155 and [Ni II]λ7378 lines are redshifted, as expected for a high velocity gradient supernova. All these common intrinsic and extrinsic properties of the high velocity gradient (HVG) group are different from the low velocity gradient (LVG) normal SN Ia population and suggest significant variety in SN Ia explosions. This paper includes data gathered with the Du Pont Telescope at Las Campanas Observatory, Chile; and the Gemini Observatory, Cerro Pachon, Chile (Gemini Program GS-2010A-Q-14). Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile (ESO Programme 085.D-0577).

  3. Gaia17biu/SN 2017egm in NGC 3191: The Closest Hydrogen-poor Superluminous Supernova to Date Is in a “Normal,” Massive, Metal-rich Spiral Galaxy

    Science.gov (United States)

    Bose, Subhash; Dong, Subo; Pastorello, A.; Filippenko, Alexei V.; Kochanek, C. S.; Mauerhan, Jon; Romero-Cañizales, C.; Brink, Thomas G.; Chen, Ping; Prieto, J. L.; Post, R.; Ashall, Christopher; Grupe, Dirk; Tomasella, L.; Benetti, Stefano; Shappee, B. J.; Stanek, K. Z.; Cai, Zheng; Falco, E.; Lundqvist, Peter; Mattila, Seppo; Mutel, Robert; Ochner, Paolo; Pooley, David; Stritzinger, M. D.; Villanueva, S., Jr.; Zheng, WeiKang; Beswick, R. J.; Brown, Peter J.; Cappellaro, E.; Davis, Scott; Fraser, Morgan; de Jaeger, Thomas; Elias-Rosa, N.; Gall, C.; Gaudi, B. Scott; Herczeg, Gregory J.; Hestenes, Julia; Holoien, T. W.-S.; Hosseinzadeh, Griffin; Hsiao, E. Y.; Hu, Shaoming; Jaejin, Shin; Jeffers, Ben; Koff, R. A.; Kumar, Sahana; Kurtenkov, Alexander; Lau, Marie Wingyee; Prentice, Simon; Reynolds, T.; Rudy, Richard J.; Shahbandeh, Melissa; Somero, Auni; Stassun, Keivan G.; Thompson, Todd A.; Valenti, Stefano; Woo, Jong-Hak; Yunus, Sameen

    2018-01-01

    Hydrogen-poor superluminous supernovae (SLSNe-I) have been predominantly found in low-metallicity, star-forming dwarf galaxies. Here we identify Gaia17biu/SN 2017egm as an SLSN-I occurring in a “normal” spiral galaxy (NGC 3191) in terms of stellar mass (several times 1010 M⊙) and metallicity (roughly solar). At redshift z = 0.031, Gaia17biu is also the lowest-redshift SLSN-I to date, and the absence of a larger population of SLSNe-I in dwarf galaxies of similar redshift suggests that metallicity is likely less important to the production of SLSNe-I than previously believed. With the smallest distance and highest apparent brightness for an SLSN-I, we are able to study Gaia17biu in unprecedented detail. Its pre-peak near-ultraviolet to optical color is similar to that of Gaia16apd and among the bluest observed for an SLSN-I, while its peak luminosity (Mg = ‑21 mag) is substantially lower than that of Gaia16apd. Thanks to the high signal-to-noise ratios of our spectra, we identify several new spectroscopic features that may help to probe the properties of these enigmatic explosions. We detect polarization at the ∼0.5% level that is not strongly dependent on wavelength, suggesting a modest, global departure from spherical symmetry. In addition, we put the tightest upper limit yet on the radio luminosity of an SLSN-I with central engines.

  4. TYPE Ia SUPERNOVA PROGENITORS AND CHEMICAL ENRICHMENT IN HYDRODYNAMICAL SIMULATIONS. I. THE SINGLE-DEGENERATE SCENARIO

    Energy Technology Data Exchange (ETDEWEB)

    Jiménez, Noelia [School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, KY16 9SS, Scotland (United Kingdom); Tissera, Patricia B. [Instituto de Astronomía y Física del Espacio (IAFE, CONICET-UBA), CC. 67 Suc. 28, C1428ZAA, Ciudad de Buenos Aires (Argentina); Matteucci, Francesca, E-mail: nj22@st-andrews.ac.uk [Dipartimento di Fisica, Universita’ di Trieste, Via G. B. Tiepolo, 11, I-34100, Trieste (Italy)

    2015-09-10

    The nature of the Type Ia supernova (SN Ia) progenitors remains uncertain. This is a major issue for galaxy evolution models since both chemical and energetic feedback plays a major role in the gas dynamics, star formation, and therefore the overall stellar evolution. The progenitor models for the SNe Ia available in the literature propose different distributions for regulating the explosion times of these events. These functions are known as the delay time distributions (DTDs). This work is the first one in a series of papers aiming at studying five different DTDs for SNe Ia. Here we implement and analyze the single-degenerate (SD) scenario in galaxies dominated by a rapid quenching of the star formation, displaying the majority of the stars concentrated in the bulge component. We find a good fit to both the present observed SN Ia rates in spheroidal-dominated galaxies and the [O/Fe] ratios shown by the bulge of the Milky Way. Additionally, the SD scenario is found to reproduce a correlation between the specific SN Ia rate and the specific star formation rate (sSFR), which closely resembles the observational trend, at variance with previous works. Our results suggest that SN Ia observations in galaxies with very low and very high sSFRs can help to impose more stringent constraints on the DTDs and therefore on SN Ia progenitors.

  5. The effect of peculiar velocities on supernova cosmology

    DEFF Research Database (Denmark)

    Davis, Tamara Maree; Hui, Lam; Frieman, Joshua A.

    2011-01-01

    We analyze the effect that peculiar velocities have on the cosmological inferences we make using luminosity distance indicators, such as Type Ia supernovae. In particular we study the corrections required to account for (1) our own motion, (2) correlations in galaxy motions, and (3) a possible...... local under- or overdensity. For all of these effects we present a case study showing the impact on the cosmology derived by the Sloan Digital Sky Survey-II Supernova Survey (SDSS-II SN Survey). Correcting supernova (SN) redshifts for the cosmic microwave background (CMB) dipole slightly overcorrects...

  6. Supernovae and Gamma-Ray Bursts

    Science.gov (United States)

    Livio, Mario; Panagia, Nino; Sahu, Kailash

    2001-07-01

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

  7. Gamma-ray constraints on supernova nucleosynthesis

    Science.gov (United States)

    Leising, Mark D.

    1994-01-01

    Gamma-ray spectroscopy holds great promise for probing nucleosynthesis in individual supernova explosions via short-lived radioactivity, and for measuring current global Galactic supernova nucleosynthesis with longer-lived radioactivity. It was somewhat surprising that the former case was realized first for a Type II supernova, when both Co-56 and Co-57 were detected in SN 1987A. These provide unprecedented constraints on models of Type II explosions and nucleosynthesis. Live Al-26 in the Galaxy might come from Type II supernovae, and if it is eventually shown to be so, can constrain massive star evolution, supernova nucleosynthesis, and the Galactic Type II supernova rate. Type Ia supernovae, thought to be thermonuclear explosions, have not yet been detected in gamma-rays. This is somewhat surprising given current models and recent Co-56 detection attempts. Ultimately, gamma-ray measurements can confirm their thermonuclear nature, probe the nuclear burning conditions, and help evaluate their contributions to Galactic nucleosynthesis. Type Ib/c supernovae are poorly understood. Whether they are core collapse or thermonuclear events might be ultimately settled by gamma-ray observations. Depending on details of the nuclear processing, any of these supernova types might contribute to a detectable diffuse glow of Fe-60 gamma-ray lines. Previous attempts at detection have come very close to expected emission levels. Remnants of any type of age less that a few centuries might be detectable as individual spots of Ti-44 gamma-ray line emission. It is in fact quite surprising that previous surveys have not discovered such spots, and the constraints on the combination of nucleosynthesis yields and supernova rates are very interesting. All of these interesting limits and possibilities mean that the next mission, International Gamma-Ray Astrophysics Laboratory (INTEGRAL), if it has sufficient sensitivity, is very likely to lead to the realization of much of the great potential

  8. Galex and Pan-STARRS1 Discovery of SN IIP 2010aq: The First Few Days After Shock Breakout in a Red Supergiant Star

    Science.gov (United States)

    2010-09-01

    present the early UV and optical light curve of Type IIP supernova (SN) 2010aq at z = 0.0862, and compare it to analytical models for thermal emission... supernovae : individual (SN 2010aq) – surveys – ultraviolet: general 1. INTRODUCTION Shock breakout in a core-collapse supernova (SN) marks the first escape...rich Type II-plateau SNe (SNe IIP), a receding H recombination wave prolongs the optical brightness of the SN until radioactive heating plays a

  9. The Nearby Galaxies Supernova Search project: The rate of supernovae in the local universe

    Science.gov (United States)

    Strolger, Louis-Gregory

    2003-08-01

    Over 2200 supernova events have been discovered in the past millenium—nearly half of which have been found in only the last decade. The rise in interest in these events has been sparked, in large part, by the sample of distant Type Ia supernovae which are giving unprecedented information about the cosmological parameters of our Universe. However, when one considers that very little is known about several SN Types including the Type Ia events, it is clear that there remains much to be understood in the detailed analysis of supernovae. Currently, this analysis is best done through relatively low redshift supernova surveys. Here I present the results from the Nearby Galaxies Supernova Search project (NGSS), a three-year survey for SNe in equatorial field galaxies. Through the bulk analysis of these SNe, I have determined the local SN rates in field galaxies (in Supernova Units [SNu]; Supernovae per century per 1010 LB⊙ ) to be 0.192 ± 0.045 (Poisson) ± 0.094 (systematic) for Type Ia SNe, 0.678 ± 0.164 ± 0.278 to 1.242 ± 0.301 ± 0.514 for Type II SNe, and 1.166 ± 0.178 ± 0.498 to 1.924 ± 0.293 ± 0.887 for all supernova types (depending on assumed intrinsic extinction distributions for core-collapse events). A small number of SNe from this survey were also attributed to Abell galaxy clusters. Although there was not a sufficient sample in which to draw conclusive rates, through simple assumptions about galaxy cluster mass, size, and luminosity parameters, I estimate the supernova rate to be 0.46 ± 0.14 (Poisson) to 0.84 ± 0.26 SNu in these environments (also dependent on extinction distributions). In the course of this survey, we discovered a number of rare SN types, including SN 1999aw, a SN 1999aa-like Type Ia in a very low-luminosity host galaxy. We have completed a very thorough analysis of this luminous and peculiar event, which I include in this dissertation. The NGSS project has successfully discovered one of the largest samples of SNe from a

  10. Multiwavelength observations of the Type IIb supernova 2009mg

    DEFF Research Database (Denmark)

    Oates, S. R.; Bayless, A. J.; Stritzinger, M. D.

    2012-01-01

    We present Swift Ultra-Violet Optical Telescope and X-Ray Telescope (XRT) observations, and visual wavelength spectroscopy of the Type IIb supernova (SN) 2009mg, discovered in the Sb galaxy ESO 121-G26. The observational properties of SN 2009mg are compared to the prototype Type IIb SNe 1993J...

  11. Energetic Systems

    Data.gov (United States)

    Federal Laboratory Consortium — The Energetic Systems Division provides full-spectrum energetic engineering services (project management, design, analysis, production support, in-service support,...

  12. Left Behind: A Bound Remnant from a White Dwarf Supernova?

    Science.gov (United States)

    Jha, Saurabh

    2017-08-01

    Type Ia supernovae (SN Ia) have enormous importance to cosmology and astrophysics, but their progenitors and explosion mechanisms are not understood in detail. Recently, observations and theoretical models have suggested that not all thermonuclear white-dwarf supernova explosions are normal SN Ia. In particular, type Iax supernovae (peculiar cousins to SN Ia), are thought to be exploding white dwarfs that are not completely disrupted, leaving behind a bound remnant. In deep and serendipitous HST pre-explosion data, we have discovered a luminous, blue progenitor system for the type Iax SN 2012Z in NGC 1309, which we interpret as a helium-star donor to the exploding white dwarf. HST observations of SN 2012Z in 2016, when the supernova light was expected to have faded away, still show a source at the location, as expected in our model where the pre-explosion flux was coming from the companion. However, the 2016 data also show a surprise: an excess flux compared to the progenitor system. Our proposed observations here will help unravel the mystery of that excess flux: is it from the bound ex-white dwarf remnant? Or is it from the shocked companion star that has been bombarded by supernova ejecta? Either of these possibilities would provide key new evidence as to the nature of these white dwarf supernovae.

  13. Supernova constraints on neutrino mass and mixing

    Indian Academy of Sciences (India)

    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 ...

  14. Magnetorotational Explosions of Core-Collapse Supernovae

    Directory of Open Access Journals (Sweden)

    Gennady S. Bisnovatyi-Kogan

    2014-12-01

    Full Text Available Core-collapse supernovae are accompanied by formation of neutron stars. The gravitation energy is transformed into the energy of the explosion, observed as SN II, SN Ib,c type supernovae. We present results of 2-D MHD simulations, where the source of energy is rotation, and magnetic eld serves as a "transition belt" for the transformation of the rotation energy into the energy of the explosion. The toroidal part of the magnetic energy initially grows linearly with time due to dierential rotation. When the twisted toroidal component strongly exceeds the poloidal eld, magneto-rotational instability develops, leading to a drastic acceleration in the growth of magnetic energy. Finally, a fast MHD shock is formed, producing a supernova explosion. Mildly collimated jet is produced for dipole-like type of the initial field. At very high initial magnetic field no MRI development was found.

  15. The Supernovae Analysis Application (SNAP)

    Science.gov (United States)

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

    2017-09-01

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

  16. 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.

  17. Gemini Spectroscopy of Supernovae from the Supernova Legacy Survey: Improving High-Redshift Supernova Selection and Classification

    Science.gov (United States)

    Howell, D. A.; Sullivan, M.; Perrett, K.; Bronder, T. J.; Hook, I. M.; Astier, P.; Aubourg, E.; Balam, D.; Basa, S.; Carlberg, R. G.; Fabbro, S.; Fouchez, D.; Guy, J.; Lafoux, H.; Neill, J. D.; Pain, R.; Palanque-Delabrouille, N.; Pritchet, C. J.; Regnault, N.; Rich, J.; Taillet, R.; Knop, R.; McMahon, R. G.; Perlmutter, S.; Walton, N. A.

    2005-12-01

    We present new techniques for improving the efficiency of supernova (SN) classification at high redshift using 64 candidates observed at Gemini North and South during the first year of the Supernova Legacy Survey (SNLS). The SNLS is an ongoing 5 year project with the goal of measuring the equation of state of dark energy by discovering and following over 700 high-redshift SNe Ia using data from the Canada-France-Hawaii Telescope Legacy Survey. We achieve an improvement in the SN Ia spectroscopic confirmation rate: at Gemini 71% of candidates are now confirmed as SNe Ia, compared to 54% using the methods of previous surveys. This is despite the comparatively high redshift of this sample, in which the median SN Ia redshift is z=0.81 (0.155Berthelot, 75231 Paris Cedex 05, France. DSM/DAPNIA, CEA/Saclay, 91191 Gif-sur-Yvette Cedex, France.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-03-24

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

  19. A trio of gamma-ray burst supernovae

    DEFF Research Database (Denmark)

    Cano, Z.; Ugarte Postigo, Antonio de; Pozanenko, A.

    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. In the case of GRB 130215A / SN 2013ez, we also present optical spectroscopy at t-t0=16.1 d, which covers rest-frame 3000...

  20. Multi-wavelength observations of pulsar wind nebulae and composite supernova remnants

    Science.gov (United States)

    Temim, Tea

    Multi-wavelength studies of pulsar wind nebulae (PWNe) and supernova remnants (SNRs) lead to a better understanding of their evolutionary development, the interaction of supernovae (SNe) and pulsar winds with their surroundings, and nucleosynthesis and production and processing of dust grains by SNe. PWNe and composite supernova remnants, in particular, are unique laboratories for the study of the energetic pulsar winds, particle injection processes, and the impact of PWNe on the evolving SNR. They provide information on SNR shock properties, densities and temperatures, and the chemical composition and the ionization state of the material ejected by SNe. SNRs also serve as laboratories for the study of dust production and processing in SNe. While X-ray observations yield important information about the SN progenitor, hot gas properties, SN explosion energy, and the surrounding interstellar medium (ISM), the IR can provide crucial information about the faint non-thermal emission, continuum emission from dust, and forbidden line emission from SN ejecta. Combining observations at a wide range of wavelengths provides a more complete picture of the SNR development and helps better constrain current models describing a SNR's evolution and its impact on the surrounding medium. This thesis focuses on a multi-wavelength study of PWNe in various stages of their evolution and investigates their interaction with the expanding SN ejecta and dust and the SNR reverse shock. The study of these interactions can provide important information on the SNR properties that may otherwise be unobservable. The work in this thesis has been carried out under the supervision of Patrick Slane at the Harvard-Smithsonian Center for Astrophysics, and Charles E. Woodward and Rebert D. Gehrz at the University of Minnesota. The first part of the thesis summarizes the evolution and observational properties of SNRs and PWNe, with a focus on the evolution of young PWNe that are sweeping up inner SN

  1. Photometric observations of the Type Ia SN 2002er in UGC 10743

    NARCIS (Netherlands)

    Pignata, G.; Patat, F.; Benetti, S.; Blinnikov, S.; Hillebrandt, W.; Kotak, R.; Leibundgut, B.; Mazzali, P.A.; Meikle, P.; Qiu, Y.; Ruiz-Lapuente, P.; Smartt, S.J.; Sorokina, E.; Stritzinger, M.; Stehle, M.; Turatto, M.; Martin-Luis, F.; McBride, N.; Mendez, J.; Morales-Rueda, L.; Narbutis, D.; Street, R.

    2004-01-01

    Extensive light and colour curves for the Type Ia supernova (SN Ia) SN 2002er are presented as part of the European Supernova Collaboration. We have collected UBVRI photometry from 11 different telescopes covering the phases from 7 d before until 619 d after maximum light. Corrections for the

  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. A Sample of Light Curves of Type II-n and other Unclassified Supernova

    Science.gov (United States)

    Mock, Justin; Martin, J. C.; Hambsch, F.; Strickland, W.; Cason, A.

    2014-01-01

    It has long been speculated that there is a connection between supernova impostors and Type II-n supernovae. The modern Type II-n spectroscopic classification overlaps a great deal with Zwicky’s “Type V” supernovae, which includes several impostors. In late 2012, SN 2009ip, a known impostor, may have exploded as a Type II-n supernova. The decline from that event exhibited unusual fluctuations in brightness that are not evident in other Type II-n light curves. We present the light curves of several more recent Type II-n supernova and compare them with other published samples.

  4. HOST GALAXY PROPERTIES AND HUBBLE RESIDUALS OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY

    Energy Technology Data Exchange (ETDEWEB)

    Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [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, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others

    2013-06-20

    We examine the relationship between Type Ia supernova (SN Ia) Hubble residuals and the properties of their host galaxies using a sample of 115 SNe Ia from the Nearby Supernova Factory. We use host galaxy stellar masses and specific star formation rates fitted from photometry for all hosts, as well as gas-phase metallicities for a subset of 69 star-forming (non-active galactic nucleus) hosts, to show that the SN Ia Hubble residuals correlate with each of these host properties. With these data we find new evidence for a correlation between SN Ia intrinsic color and host metallicity. When we combine our data with those of other published SN Ia surveys, we find the difference between mean SN Ia brightnesses in low- and high-mass hosts is 0.077 {+-} 0.014 mag. When viewed in narrow (0.2 dex) bins of host stellar mass, the data reveal apparent plateaus of Hubble residuals at high and low host masses with a rapid transition over a short mass range (9.8 {<=} log (M{sub *}/M{sub Sun }) {<=} 10.4). Although metallicity has been a favored interpretation for the origin of the Hubble residual trend with host mass, we illustrate how dust in star-forming galaxies and mean SN Ia progenitor age both evolve along the galaxy mass sequence, thereby presenting equally viable explanations for some or all of the observed SN Ia host bias.

  5. Photometry of High-Redshift Gravitationally Lensed Type Ia Supernovae

    Science.gov (United States)

    Haynie, Annastasia

    2018-01-01

    Out of more than 1100 well-identified Type Ia Supernovae, only roughly 10 of them are at z> 1.5. High redshift supernovae are hard to detect but this is made easier by taking advantage of the effects of gravitational lensing, which magnifies objects in the background field of massive galaxy clusters. Supernova Nebra (z= ~1.8), among others, was discovered during observations taken as part of the RELICS survey, which focused on fields of view that experience strong gravitational lensing effects. SN Nebra, which sits behind galaxy cluster Abell 1763, is magnified and therefore appears closer and easier to see than with HST alone. Studying high-redshift supernovae like SN Nebra is an important step towards creating cosmological models that accurately describe the behavior of dark energy in the early Universe. Recent efforts have been focused on improving photometry and the building and fitting of preliminary light curves.

  6. Condensation of carbon in radioactive supernova gas.

    Science.gov (United States)

    Clayton, D D; Liu, W; Dalgarno, A

    1999-02-26

    Chemistry resulting in the formation of large carbon-bearing molecules and dust in the interior of an expanding supernova was explored, and the equations governing their abundances were solved numerically. Carbon dust condenses from initially gaseous carbon and oxygen atoms because energetic electrons produced by radioactivity in the supernova cause dissociation of the carbon monoxide molecules, which would otherwise form and limit the supply of carbon atoms. The resulting free carbon atoms enable carbon dust to grow faster by carbon association than the rate at which the dust can be destroyed by oxidation. The origin of presolar micrometer-sized carbon solids that are found in meteorites is thereby altered.

  7. Three Gravitationally Lensed Supernovae Behind Clash Galaxy Clusters

    Science.gov (United States)

    Patel, Brandon; McCully, Curtis; Jha, Saurbh W.; Rodney, Steven A.; Jones, David O.; Graur, Or; Merten, Julian; Zitrin, Adi; Riess, Adam G.; Matheson, Thomas; hide

    2014-01-01

    We report observations of three gravitationally lensed supernovae (SNe) in the Cluster Lensing And Supernova survey with Hubble (CLASH) Multi-Cycle Treasury program. These objects, SN CLO12Car (z = 1.28), SN CLN12Did (z = 0.85), and SN CLA11Tib (z = 1.14), are located behind three different clusters, MACSJ1720.2+3536 (z = 0.391), RXJ1532.9+3021 (z = 0.345), and A383 (z = 0.187), respectively. Each SN was detected in Hubble Space Telescope optical and infrared images. Based on photometric classification, we find that SNe CLO12Car and CLN12Did are likely to be Type Ia supernovae (SNe Ia), while the classification of SN CLA11Tib is inconclusive. Using multi-color light-curve fits to determine a standardized SN Ia luminosity distance, we infer that SN CLO12Car was approx. 1.0 +/- 0.2 mag brighter than field SNe Ia at a similar redshift and ascribe this to gravitational lens magnification. Similarly, SN CLN12Did is approx. 0.2 +/- 0.2 mag brighter than field SNe Ia. We derive independent estimates of the predicted magnification from CLASH strong+weak-lensing maps of the clusters (in magnitude units, 2.5 log10 µ): 0.83 +/- 0.16 mag for SN CLO12Car, 0.28 +/- 0.08 mag for SN CLN12Did, and 0.43 +/- 0.11 mag for SN CLA11Tib. The two SNe Ia provide a new test of the cluster lens model predictions: we find that the magnifications based on the SN Ia brightness and those predicted by the lens maps are consistent. Our results herald the promise of future observations of samples of cluster-lensed SNe Ia (from the ground or space) to help illuminate the dark-matter distribution in clusters of galaxies, through the direct determination of absolute magnifications.

  8. The Supernova Spectropolarimetry (SNSPOL) Project; Probing the Geometry of Supernova Explosions

    Science.gov (United States)

    Williams, George Grant; Leonard, Douglas; Smith, Nathan; Smith, Paul; Milne, Peter; Hoffman, Jennifer L.; Bilinski, Christopher

    2018-01-01

    In recent years, evidence has grown that most supernovae exhibit departures from spherical symmetry. These results, together with full three-dimensional modeling, are exposing the possibility that asymmetries are not simply an observable feature of some supernovae, but may, in fact, be a necessity of the explosion mechanism itself. However, with the exception of SN 1987A, a supernova photosphere cannot be resolved through direct imaging from ground or space. Only the powerful technique of polarimetry can directly probe asymmetries on those spatial scales. Spectropolarimetry enhances the power of this technique by revealing wavelength-dependent variations that may result from differences in the geometrical distributions of the various ionic species. Multi-epoch observations over several months can be used to follow the evolution of these asymmetries as a supernova evolves and its photosphere recedes through the ejecta. The Supernova Spectropolarimetry (SNSPOL) Project aims to study the predominance and characteristics of asymmetries in all types of supernovae by decoding their complex, time-dependent polarimetric behavior. This is accomplished through multi-epoch observations using the CCD Imaging/Spectropolarimeter (SPOL) on the 61” Kuiper, the 90” Bok, and the 6.5-m MMT telescopes. During the past six years, the SNSPOL Project has observed more than 95 supernovae, approximately 2/3 of which have been observed at multiple epochs. Here we present a summary of the project, its current status, and a few selected results.

  9. Dark Matter Ignition of Type Ia Supernovae.

    Science.gov (United States)

    Bramante, Joseph

    2015-10-02

    Recent studies of low redshift type Ia supernovae (SN Ia) indicate that half explode from less than Chandrasekhar mass white dwarfs, implying ignition must proceed from something besides the canonical criticality of Chandrasekhar mass SN Ia progenitors. We show that 1-100 PeV mass asymmetric dark matter, with imminently detectable nucleon scattering interactions, can accumulate to the point of self-gravitation in a white dwarf and collapse, shedding gravitational potential energy by scattering off nuclei, thereby heating the white dwarf and igniting the flame front that precedes SN Ia. We combine data on SN Ia masses with data on the ages of SN Ia-adjacent stars. This combination reveals a 2.8σ inverse correlation between SN Ia masses and ignition ages, which could result from increased capture of dark matter in 1.4 vs 1.1 solar mass white dwarfs. Future studies of SN Ia in galactic centers will provide additional tests of dark-matter-induced type Ia ignition. Remarkably, both bosonic and fermionic SN Ia-igniting dark matter also resolve the missing pulsar problem by forming black holes in ≳10  Myr old pulsars at the center of the Milky Way.

  10. Predicting the nature of supernova progenitors

    Science.gov (United States)

    Groh, Jose H.

    2017-09-01

    Stars more massive than about 8 solar masses end their lives as a supernova (SN), an event of fundamental importance Universe-wide. The physical properties of massive stars before the SN event are very uncertain, both from theoretical and observational perspectives. In this article, I briefly review recent efforts to predict the nature of stars before death, in particular, by performing coupled stellar evolution and atmosphere modelling of single stars in the pre-SN stage. These models are able to predict the high-resolution spectrum and broadband photometry, which can then be directly compared with the observations of core-collapse SN progenitors. The predictions for the spectral types of massive stars before death can be surprising. Depending on the initial mass and rotation, single star models indicate that massive stars die as red supergiants, yellow hypergiants, luminous blue variables and Wolf-Rayet stars of the WN and WO subtypes. I finish by assessing the detectability of SN Ibc progenitors. This article is part of the themed issue 'Bridging the gap: from massive stars to supernovae'.

  11. 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.

  12. Why did Supernova 1054 shine at late times?

    OpenAIRE

    Sollerman, Jesper; Kozma, Cecilia; Lundqvist, Peter

    2000-01-01

    The Crab nebula is the remnant of supernova 1054 (SN 1054). The progenitor of this supernova has, based on nucleosynthesis arguments, been modeled as an 8-10 solar mass star. Here we point out that the observations of the late light curve of SN 1054, from the historical records, are not compatible with the standard scenario, in which the late time emission is powered by the radioactive decay of small amounts of Ni-56. Based on model calculations we quantify this discrepancy. The rather large ...

  13. Generation of Cosmic rays in Historical Supernova Remnants

    Directory of Open Access Journals (Sweden)

    Sinitsyna V.Y.

    2013-06-01

    Full Text Available We present the results of observations of two types of Galactic supernova remnants with the SHALON mirror Cherenkov telescope of Tien-Shan high-mountain Observatory: the shell-type supernova remnants Tycho, Cas A and IC 443; plerions Crab Nebula, 3c58(SN1181 and Geminga (probably plerion. The experimental data have confirmed the prediction of the theory about the hadronic generation mechanism of very high energy (800 GeV - 100 TeV gamma-rays in Tycho's supernova remnant. The data obtainedsuggest that the very high energy gamma-ray emission in the objects being discussedis different in origin.

  14. PUSHing Core-Collapse Supernovae to Explosions in Spherical Symmetry: Nucleosynthesis Yields

    Science.gov (United States)

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

    Core-collapse supernovae (CCSNe) are the extremely energetic deaths of massive stars. They play a vital role in the synthesis and dissemination of many heavy elements in the universe. In the past, CCSN nucleosynthesis calculations have relied on artificial explosion methods that do not adequately capture the physics of the innermost layers of the star. The PUSH method, calibrated against SN1987A, utilizes the energy of heavy-flavor neutrinos emitted by the proto-neutron star (PNS) to trigger parametrized explosions. This makes it possible to follow the consistent evolution of the PNS and to ensure a more accurate treatment of the electron fraction of the ejecta. Here, we present the Iron group nucleosynthesis results for core-collapse supernovae, exploded with PUSH, for two different progenitor series. Comparisons of the calculated yields to observational metal-poor star data are also presented. Nucleosynthesis yields will be calculated for all elements and over a wide range of progenitor masses. These yields can be immensely useful for models of galactic chemical evolution.

  15. ASASSN-17hp: Discovery of A Probable Supernova in ESO 575-G066

    Science.gov (United States)

    Fernandez, J. M.; Cacella, P.; Brimacombe, J.; Brown, J. S.; Stanek, K. Z.; Holoien, T. W.-S.; Kochanek, C. S.; Shields, J.; Thompson, T. A.; Shappee, B. J.; Prieto, J. L.; Bersier, D.; Dong, Subo; Bose, S.; Chen, Ping; Nicholls, B.

    2017-06-01

    During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014), using data from the quadruple 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy ESO 575-G066.

  16. SN 2009ip and SN 2010mc as dual-shock Quark-Novae

    OpenAIRE

    Ouyed, Rachid; Koning, Nico; Leahy, Denis

    2013-01-01

    In recent years a number of double-humped supernovae have been discovered. This is a feature predicted by the dual-shock Quark-Nova model where a SN explosion is followed (a few days to a few weeks later) by a Quark-Nova explosion. SN 2009ip and SN 2010mc are the best observed examples of double-humped SNe. Here, we show that the dual-shock Quark-Nova model naturally explains their lightcurves including the late time emission, which we attribute to the interaction between the mixed SN and QN ...

  17. Supernovae and gamma-ray bursts connection

    Energy Technology Data Exchange (ETDEWEB)

    Valle, Massimo Della [INAF-Napoli, Capodimonte Observatory, Salita Moiariello, 16, I-80131 Napoli (Italy); International Center for Relativistic Astrophysics Network, Piazzale della Repubblica 10, I-65122, Pescara (Italy)

    2015-12-17

    I’ll review the status of the Supernova/Gamma-Ray Burst connection. Several pieces of evidence suggest that long duration Gamma-ray Bursts are associated with bright SNe-Ic. However recent works suggest that GRBs might be produced in tight binary systems composed of a massive carbon-oxygen cores and a neutron star companion. Current estimates of the SN and GRB rates yield a ratio GRB/SNe-Ibc in the range ∼ 0.4% − 3%.

  18. Average Spectral Properties of Type Ia Supernova Host Galaxies

    Science.gov (United States)

    Uddin, Syed A.; Mould, Jeremy; Wang, Lifan

    2017-12-01

    We construct the average spectra of host galaxies of slower, faster, bluer, and redder Type Ia supernovae (SNe Ia) from the SDSS-II supernova survey. The average spectrum of slower declining (broader light curve width or higher stretch) SN Ia hosts shows stronger emission lines compared to the average spectrum of faster declining (narrower light curve width or lower stretch) SN Ia hosts. Using pPXF, we find that hosts of slower declining SNe Ia have metallicities that are, on average, 0.24 dex lower than average metallicities of faster declining SN Ia hosts. Similarly, redder SN Ia hosts have slightly higher metallicities than bluer SN Ia hosts. Lick index analysis of metallic lines and Balmer lines shows that faster declining SN Ia hosts have relatively higher metal content and have relatively older stellar populations compared with slower declining SN Ia hosts. We calculate average {{{H}}}α star formation rate (SFR), stellar mass, and the specific SFR (sSFR) of host galaxies in these subgroups of SNe Ia. We find that slower declining SN Ia hosts have significantly higher (> 5σ ) sSFR than faster declining SN Ia hosts. A Kolmogorov-Smirnov test shows that these two types of hosts originate from different parent distributions. Our results, when compared with the models of Childress et al., indicate that slower declining SNe Ia, being hosted in actively star-forming galaxies, are young (prompt) SNe Ia, originating from similar progenitor age groups.

  19. Millisecond Magnetar Birth Connects FRB 121102 to Superluminous Supernovae and Long-duration Gamma-Ray Bursts

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, Brian D.; Margalit, Ben [Columbia Astrophysics Laboratory, New York, NY 10027 (United States); Berger, Edo [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2017-05-20

    Subarcsecond localization of the repeating fast radio burst FRB 121102 revealed its coincidence with a dwarf host galaxy and a steady (“quiescent”) nonthermal radio source. We show that the properties of the host galaxy are consistent with those of long-duration gamma-ray bursts (LGRB) and hydrogen-poor superluminous supernovae (SLSNe-I). Both LGRBs and SLSNe-I were previously hypothesized to be powered by the electromagnetic spin-down of newly formed, strongly magnetized neutron stars with millisecond birth rotation periods (“millisecond magnetars”). This motivates considering a scenario whereby the repeated bursts from FRB 121102 originate from a young magnetar remnant embedded within a young hydrogen-poor supernova (SN) remnant. Requirements on the gigahertz free–free optical depth through the expanding SN ejecta (accounting for photoionization by the rotationally powered magnetar nebula), energetic constraints on the bursts, and constraints on the size of the quiescent source all point to an age of less than a few decades. The quiescent radio source can be attributed to synchrotron emission from the shock interaction between the fast outer layer of the supernova ejecta with the surrounding wind of the progenitor star, or the radio source can from deeper within the magnetar wind nebula as outlined in Metzger et al. Alternatively, the radio emission could be an orphan afterglow from an initially off-axis LGRB jet, though this might require the source to be too young. The young age of the source can be tested by searching for a time derivative of the dispersion measure and the predicted fading of the quiescent radio source. We propose future tests of the SLSNe-I/LGRB/FRB connection, such as searches for FRBs from nearby SLSNe-I/LGRBs on timescales of decades after their explosions.

  20. Spectroscopic observation of SN 2016ijk and SN 2016iuc by NUTS (NOT Un-biased Transient Survey)

    Science.gov (United States)

    Kangas, T.; Mattila, S.; Lundqvist, P.; Taddia, F.; Kuncarayakti, H.; Harmanen, J.; Somero, A.; Reynolds, T.; Ergon, M.

    2016-12-01

    The Nordic Optical Telescope (NOT) Unbiased Transient Survey (NUTS; ATel #8992) reports the spectroscopic classification of the supernovae SN 2016ijk/Gaia16car in the host galaxy 2MASX J01290449+4021466 and SN 2016iuc/Gaia16cay in the host galaxy NGC 5032.

  1. Spectroscopic observation of SN 2016ieq and SN 2016isg by NUTS (NOT Un-biased Transient Survey)

    Science.gov (United States)

    Kangas, T.; Mattila, S.; Stritzinger, M.; Dong, S.; Hsiao, E.; Lundqvist, P.; Taddia, F.; Kankare, E.; Kuncarayakti, H.; Harmanen, J.; Somero, A.; Reynolds, T.; Ergon, M.; Gafton, E.

    2016-12-01

    The Nordic Optical Telescope (NOT) Unbiased Transient Survey (NUTS; ATel #8992) reports the spectroscopic classification of the supernovae SN 2016ieq/Gaia16buy in the host galaxy APMUKS(BJ) B211942.51-120949.1 and SN 2016isg/ASASSN-16oo in the host galaxy 2MASX J01411858-0012382.

  2. 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

  3. Measuring the Cosmic-Ray Acceleration Efficiency of a Supernova Remnant

    National Research Council Canada - National Science Library

    E. A. Helder; J. Vink; C. G. Bassa; A. Bamba; J. A. M. Bleeker; S. Funk; P. Ghavamian; K. J. van der Heyden; F. Verbunt; R. Yamazaki

    2009-01-01

    Cosmic rays are the most energetic particles arriving at Earth. Although most of them are thought to be accelerated by supernova remnants, the details of the acceleration process and its efficiency are not well determined...

  4. X-ray spectral analysis of non-equilibrium plasmas in supernova remnants

    NARCIS (Netherlands)

    Broersen, S.

    2014-01-01

    Supernovae are some of the most energetic events known in the Universe. For a short time they can shine as bright as their entire Galaxy, allowing us to observe them up till very large distances. Supernovae are the result of the explosion of either a white dwarf, or a star with a mass about five

  5. Supernova Detection with SNO+

    Energy Technology Data Exchange (ETDEWEB)

    Schumaker, M.A. [Department of Physics, Laurentian University, Sudbury, Ontario, P3E 2C6 (Canada)

    2012-08-15

    Part of the SNO+ experimental program is the preparation for detection of neutrinos from a supernova. Tests of the acquisition chain, neutrino collective effects, and the SuperNova Early-Warning System (SNEWS) are discussed.

  6. Orbital Characteristics of Binary Systems after Asymmetric Supernova Explosions

    OpenAIRE

    Kalogera, Vassiliki

    1996-01-01

    We present an analytical method for studying the changes of the orbital characteristics of binary systems with circular orbits due to a kick velocity imparted to the newborn neutron star during a supernova explosion (SN). Assuming a Maxwellian distribution of kick velocities we derive analytical expressions for the distribution functions of orbital separations and eccentricities immediately after the explosion, of orbital separations after circularization of the post-SN orbits, and of systemi...

  7. Detecting First Supernovae with JWST

    Science.gov (United States)

    Regos, Eniko; FLARE

    2018-01-01

    We have applied for a JWST ERS First Transients Survey, FLARE to answer empirically how the Universe made its first stars. To quest the epoch of reionization we target what happened to these first stars by observing the most luminous events, supernovae. These transients provide direct constraints on star formation rates and the initial mass function.These very rare events can be reached by JWST at 27 mag AB in 2 micron and 4.4 micron over a field of 0.1 square degree visited multiple times each year.The survey may detect massive Pop III SNe at redshifts up to 10, pinpointing the redshift of first stars, a key scientific goal of JWST.We explore all models of star formation history (derived from UV luminosity densities and IR data), DTD, top heavy IMF of early, low metallicity stars, and normalizations to data of SN Ia, II rates (SNLS, CLASH, CANDELS, SDSS, SVISS), as well as SLSN (ROTSE, SNLS) to estimate the expected SN rates as function of redshift.Population synthesis of double degenerate and single degenerate scenarios of SN Ia shows that the shape of the DTD is rather insensitive to the assumptions (common envelope prescription and metallicities, or retention efficiency of accreted H to white dwarf core and mass transfer rate).Indeed GOODS High z SN Ia rates imply substantial delay in their progenitor model, and Hubble Higher z SN search constrains delay time distribution models as well.SLSN (I, II /H/ and extreme rare pulsational pair instability) are magnetars (ULGRB) in high local star formation rate, faint, low metallicity galaxies.

  8. Light-curve and spectral properties of ultra-stripped core-collapse supernovae

    Science.gov (United States)

    Moriya, Takashi J.

    2017-11-01

    We discuss light-curve and spectral properties of ultra-stripped core-collapse supernovae. Ultra-stripped supernovae are supernovae with ejecta masses of only ~0.1M ⊙ whose progenitors lose their envelopes due to binary interactions with their compact companion stars. We follow the evolution of an ultra-stripped supernova progenitor until core collapse and perform explosive nucleosynthesis calculations. We then synthesize light curves and spectra of ultra-stripped supernovae based on the nucleosynthesis results. We show that ultra-stripped supernovae synthesize ~0.01M ⊙ of the radioactive 56Ni, and their typical peak luminosity is around 1042 erg s-1 or -16 mag. Their typical rise time is 5 - 10 days. By comparing synthesized and observed spectra, we find that SN 2005ek and some of so-called calcium-rich gap transients like PTF10iuv may be related to ultra-stripped supernovae.

  9. The Fast Evolution of SN 2010bh Associated with XRF 100316D

    Science.gov (United States)

    Olivares E., F.; Greiner, J.; Schady, P.; Rau, A.; Klose, S.; Kruhler, T.; Afonso, P. M. J.; Updike, A. C.; Nardini, M.; Filgas, R.; hide

    2012-01-01

    most rapidly evolving GRB-SNe to date. Modelling of the quasi-bolometric light curve yields M(sub Ni) = 0.21 +/- 0.03 solar M and M(sub ej) = 2.6 +/- 0.2 solar M, typical of values within the GRB-SN population. The kinetic energy is E(sub k) = (2.4 +/- 0.7) x 10(exp 52) erg, which is making this SN the second most energetic GRB-SN after SN 1998bw. Conclusions. This supernova has one of the earliest peaks ever recorded and thereafter fades more rapidly than other GRB-SNe, hypernovae, or typical type-Ic SNe. This could be explained by a thin envelope expanding at very high velocities, which is therefore unable to retain the gamma-rays that would prolong the duration of the SN event.

  10. Eta Carinae and the Supernova Impostors

    CERN Document Server

    Humphreys, Roberta

    2012-01-01

    In 1965 Fritz Zwicky proposed a class of supernovae that he called "Type V", described as "excessively faint at maximum." There were only two members, SN1961v and eta Carinae. We now know that eta Carinae was not a true supernova, but if it were observed today in a distant galaxy we would call it a "supernova impostor." 170 years ago it experienced a "great eruption" lasting 20 years, expelling 10 solar masses or more, and survived. Eta Carinae is now acknowledged as the most massive, most luminous star in our region of the Galaxy, and it may be our only accessible example of a very massive star in a pre-supernova state. In this book the editors and contributing authors review its remarkable history, physical state of the star and its ejecta, and its continuing instability. Chapters also include its relation to other massive, unstable stars, the massive star progenitors of supernovae, and the "first" stars in the Universe.

  11. Are Superluminous Supernovae and Long GRBs the Products of Dynamical Processes in Young Dense Star Clusters?

    Science.gov (United States)

    van den Heuvel, E. P. J.; Portegies Zwart, S. F.

    2013-12-01

    Superluminous supernovae (SLSNe) occur almost exclusively in small galaxies (Small/Large Magellanic Cloud (SMC/LMC)-like or smaller), and the few SLSNe observed in larger star-forming galaxies always occur close to the nuclei of their hosts. Another type of peculiar and highly energetic supernovae are the broad-line Type Ic SNe (SN Ic-BL) that are associated with long-duration gamma-ray bursts (LGRBs). Also these have a strong preference for occurring in small (SMC/LMC-like or smaller) star-forming galaxies, and in these galaxies LGRBs always occur in the brightest spots. Studies of nearby star-forming galaxies that are similar to the hosts of LGRBs show that these brightest spots are giant H II regions produced by massive dense young star clusters with many hundreds of O- and Wolf-Rayet-type stars. Such dense young clusters are also found in abundance within a few hundred parsecs from the nucleus of larger galaxies like our own. We argue that the SLSNe and the SNe Ic-BL/LGRBs are exclusive products of two types of dynamical interactions in dense young star clusters. In our model the high angular momentum of the collapsing stellar cores required for the engines of an SN Ic-BL results from the post-main-sequence mergers of dynamically produced cluster binaries with almost equal-mass components. The merger produces a critically rotating single helium star with sufficient angular momentum to produce an LGRB; the observed "metal aversion" of LGRBs is a natural consequence of the model. We argue that, on the other hand, SLSNe could be the products of runaway multiple collisions in dense clusters, and we present (and quantize) plausible scenarios of how the different types of SLSNe can be produced.

  12. Are superluminous supernovae and long GRBs the products of dynamical processes in young dense star clusters?

    Energy Technology Data Exchange (ETDEWEB)

    Van den Heuvel, E. P. J. [Astronomical Institute Anton Pannekoek, University of Amsterdam, P.O. Box 94249, 1090 GE Amsterdam (Netherlands); Portegies Zwart, S. F. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)

    2013-12-20

    Superluminous supernovae (SLSNe) occur almost exclusively in small galaxies (Small/Large Magellanic Cloud (SMC/LMC)-like or smaller), and the few SLSNe observed in larger star-forming galaxies always occur close to the nuclei of their hosts. Another type of peculiar and highly energetic supernovae are the broad-line Type Ic SNe (SN Ic-BL) that are associated with long-duration gamma-ray bursts (LGRBs). Also these have a strong preference for occurring in small (SMC/LMC-like or smaller) star-forming galaxies, and in these galaxies LGRBs always occur in the brightest spots. Studies of nearby star-forming galaxies that are similar to the hosts of LGRBs show that these brightest spots are giant H II regions produced by massive dense young star clusters with many hundreds of O- and Wolf-Rayet-type stars. Such dense young clusters are also found in abundance within a few hundred parsecs from the nucleus of larger galaxies like our own. We argue that the SLSNe and the SNe Ic-BL/LGRBs are exclusive products of two types of dynamical interactions in dense young star clusters. In our model the high angular momentum of the collapsing stellar cores required for the engines of an SN Ic-BL results from the post-main-sequence mergers of dynamically produced cluster binaries with almost equal-mass components. The merger produces a critically rotating single helium star with sufficient angular momentum to produce an LGRB; the observed 'metal aversion' of LGRBs is a natural consequence of the model. We argue that, on the other hand, SLSNe could be the products of runaway multiple collisions in dense clusters, and we present (and quantize) plausible scenarios of how the different types of SLSNe can be produced.

  13. SN 1006: a thousand-year perspective

    Science.gov (United States)

    Winkler, P. Frank

    2007-08-01

    We review some of the extensive historical observations of SN 1006, emphasizing estimates of its brightness at maximum. An estimate of Vmax ≈ -7.5 is consistent with what may be the most reasonable interpretation of these records and with an a posteriori calculation based on typical peak magnitudes for Type Ia supernovae together with the distance and extinction to SN 1006. We also give a brief overview of the discovery of the SN 1006 remnant in 1965, and contrast the earliest radio, optical, and X-ray observations of the remnant with recent ones, as reported in more detail by other papers in this JD09 review.

  14. In search of Mahutonga: a possible supernova recorded in Maori astronomical traditions?

    Science.gov (United States)

    Green, David A.; Orchiston, Wayne

    Maori astronomical traditions refer to Mahutonga, which can be interpreted as a possible record of a southern supernova (SN) in or near Crux. A search for any known "young" supernova remnants in this region does not reveal any obvious candidate to associate with this possible supernova. Relaxing the positional constraint somewhat, the SN of A.D. 185 near a Centauri is nearby. If this is associated with Mahutonga, then the Maori term must be a relic of an earlier Proto-Polynesian record.

  15. HST OBSERVATIONS OF THE SUPERNOVA IN M51

    Science.gov (United States)

    2002-01-01

    NASA's Hubble Space Telescope has returned the most detailed images ever of supernova 1994I which is in the 'Whirlpool Galaxy' (M51) located 20 million light-years away in the constellation Canes Venatici. The view in this picture encompasses the inner region of the galaxy's grand spiral disk, which extends all the way to the bright nucleus. An arrow points to the location of the supernova, which lies approximately 2,000 light-years from the nucleus. The supernova appears to be superposed on a diffuse background of starlight. The Hubble Space Telescope was also used to measure the spectrum of the supernova in the ultraviolet light, which can be used to analyze the chemical composition and the motion of the gas ejected in the explosion. A supernova is a violent stellar explosion which destroys a star, while ejecting the products of nuclear burning into the gas between stars. The energy for some supernova explosions comes from the collapse of a massive star to a compact neutron star, with the mass of the Sun, but the size of a city. Elements out of which the Earth is formed had their origin in ancient supernova explosions in our own Milky Way Galaxy. This supernova was discovered on April 2, 1994 by amateur astronomers and has been the target of investigations by astronomers using ground-based optical and radio telescopes and NASA's International Ultraviolet Explorer satellite. Because a supernova explosion is a billion times as bright as a star like the Sun, they can be seen to great distances and may prove useful in charting the size of the universe. These previous observations show that SN 1994I is a very unusual supernova, called 'Type Ic,' for which very few examples have been studied carefully. The ultraviolet observations made with HST will help astronomers understand what type of stellar explosion led to supernova 1994I. Further observations of SN 1994I with the Hubble Space Telescope will be able to see more deeply into the interior of the exploded star, as

  16. Type ia Supernovae Rates and Galaxy Clustering from the CFHT Supernova Legacy Survey

    Science.gov (United States)

    Graham, M. L.; Pritchet, C. J.; Sullivan, M.; Gwyn, S. D. J.; Neill, J. D.; Hsiao, E. Y.; Astier, P.; Balam, D.; Balland, C.; Basa, S.; Carlberg, R. G.; Conley, A.; Fouchez, D.; Guy, J.; Hardin, D.; Hook, I. M.; Howell, D. A.; Pain, R.; Perrett, K.; Regnault, N.; Baumont, S.; LeDu, J.; Lidman, C.; Perlmutter, S.; Ripoche, P.; Suzuki, N.; Walker, E. S.; Zhang, T.

    2008-04-01

    The Canada-France-Hawaii Telescope Supernova Legacy Survey (CFHT SNLS) has created a large homogeneous database of intermediate redshift (0.2 z influence of galaxy clustering on the SN Ia rate, over and above the expected effect due to the dependence of SFR on clustering through the morphology-density relation. We identify three cluster SNe Ia, plus three additional possible cluster SNe Ia, and find the SN Ia rate per unit mass in clusters at intermediate redshifts is consistent with the rate per unit mass in field early-type galaxies and the SN Ia cluster rate from low-redshift cluster targeted surveys. We also find the number of SNe Ia in cluster environments to be within a factor of 2 of expectations from the two-component SN Ia rate model.

  17. Cosmic Ray Energetics and Mass

    CERN Multimedia

    Baylon cardiel, J L; Wallace, K C; Anderson, T B; Copley, M

    The cosmic-ray energetics and mass (CREAM) investigation is designed to measure cosmic-ray composition to the supernova energy scale of 10$^{15}$ eV in a series of ultra long duration balloon (ULDB) flights. The first flight is planned to be launched from Antarctica in December 2004. The goal is to observe cosmic-ray spectral features and/or abundance changes that might signify a limit to supernova acceleration. The particle ($\\{Z}$) measurements will be made with a timing-based charge detector and a pixelated silicon charge detector to minimize the effect of backscatter from the calorimeter. The particle energy measurements will be made with a transition radiation detector (TRD) for $\\{Z}$ > 3 and a sampling tungsten/scintillator calorimeter for $\\{Z}$ $\\geq$1 particles, allowing inflight cross calibration of the two detectors. The status of the payload construction and flight preparation are reported in this paper.

  18. The Global Supernova Project

    Science.gov (United States)

    Howell, Dale Andrew; Global Supernova Project

    2017-06-01

    The Global Supernova Project is worldwide collaboration to study 600 supernovae of all types between May 2017 and July 2020. It is a Key Project at Las Cumbres Observatory, whose global robotic telescope network will provide lightcurves and spectra. Follow-up observations will be obtained on many other facilities, including Swift, VLA, K2, the NTT, IRTF, Keck, and Gemini. Observations are managed by the Supernova Exchange, a combination observatin database and telescope control system run by LCO. Here we report on results from the previous Supernova Key Project, and first results from the Global Supernova Project.

  19. HOST GALAXIES OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY

    Energy Technology Data Exchange (ETDEWEB)

    Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [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, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others

    2013-06-20

    We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory. Combining Galaxy Evolution Explorer (GALEX) UV data with optical and near-infrared photometry, we employ stellar population synthesis techniques to measure SN Ia host galaxy stellar masses, star formation rates (SFRs), and reddening due to dust. We reinforce the key role of GALEX UV data in deriving accurate estimates of galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are fitted simultaneously for their stellar continua and emission lines fluxes, from which we derive high-precision redshifts, gas-phase metallicities, and H{alpha}-based SFRs. With these data we show that SN Ia host galaxies present tight agreement with the fiducial galaxy mass-metallicity relation from Sloan Digital Sky Survey (SDSS) for stellar masses log(M{sub *}/M{sub Sun }) > 8.5 where the relation is well defined. The star formation activity of SN Ia host galaxies is consistent with a sample of comparable SDSS field galaxies, though this comparison is limited by systematic uncertainties in SFR measurements. Our analysis indicates that SN Ia host galaxies are, on average, typical representatives of normal field galaxies.

  20. Supernova 1572 and other newly observed stars in the literature of the time

    OpenAIRE

    Sparavigna, Amelia Carolina

    2017-01-01

    SN 1572, also known as the Tycho's Nova, was a supernova largely reported and discussed in the literature of the time. Here we talk about this literature. In the latest texts, we find also mentioned the Kepler's Nova, today known as SN 1604, and other newly observed stars. We discuss them too.

  1. The First Maximum-light Ultraviolet through Near-infrared Spectrum of a Type Ia Supernova

    DEFF Research Database (Denmark)

    Foley, Ryan J.; Kromer, Markus; Howie Marion, G.

    2012-01-01

    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...

  2. Handbook of supernovae

    CERN Document Server

    Murdin, Paul

    2017-01-01

    This reference work gathers all of the latest research in the supernova field areas to create a definitive source book on supernovae, their remnants and related topics. It includes each distinct subdiscipline, including stellar types, progenitors, stellar evolution, nucleosynthesis of elements, supernova types, neutron stars and pulsars, black holes, swept up interstellar matter, cosmic rays, neutrinos from supernovae, supernova observations in different wavelengths, interstellar molecules and dust. While there is a great deal of primary and specialist literature on supernovae, with a great many scientific groups around the world focusing on the phenomenon and related subdisciplines, nothing else presents an overall survey. This handbook closes that gap at last. As a comprehensive and balanced collection that presents the current state of knowledge in the broad field of supernovae, this is to be used as a basis for further work and study by graduate students, astronomers and astrophysicists working in close/r...

  3. 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.

  4. The Story of Supernova “Refsdal” Told by Muse

    NARCIS (Netherlands)

    Grillo, C.; Karman, W.; Suyu, S. H.; Rosati, P.; Balestra, I.; Mercurio, A.; Lombardi, M.; Treu, T.; Caminha, G. B.; Halkola, A.; Rodney, S. A.; Gavazzi, R.; Caputi, K. I.

    2016-01-01

    We present Multi Unit Spectroscopic Explorer (MUSE) observations in the core of the Hubble Frontier Fields (HFF) galaxy cluster MACS J1149.5+2223, where the first magnified and spatially resolved multiple images of supernova (SN) "Refsdal" at redshift 1.489 were detected. Thanks to a Director's

  5. Pair creation supernovae at low and high redshift

    NARCIS (Netherlands)

    Langer, N.|info:eu-repo/dai/nl/304829498; Norman, C.A.; de Koter, A.; Vink, J.|info:eu-repo/dai/nl/182880559; Cantiello, M.|info:eu-repo/dai/nl/304840866; Yoon, S.C.|info:eu-repo/dai/nl/266576753

    2007-01-01

    Aims:Pair creation supernovae (PCSN) are thought to be produced from very massive low metallicity stars. The spectacularly bright SN 2006gy does show several signatures expected from PCSNe. Here, we investigate the metallicity threshold below which PCSN can form and estimate their occurrence rate.

  6. Pair creation supernovae at low and high redshift

    NARCIS (Netherlands)

    Langer, N.; Norman, C.A.; de Koter, A.; Vink, J.S.; Cantiello, M.; Yoon, S.C.

    2007-01-01

    Aims.Pair creation supernovae (PCSN) are thought to be produced from very massive low metallicity stars. The spectacularly bright SN 2006gy does show several signatures expected from PCSNe. Here, we investigate the metallicity threshold below which PCSN can form and estimate their occurrence rate.

  7. Jet triggered Type Ia supernovae in radio-galaxies?

    OpenAIRE

    Capetti, Alessandro

    2002-01-01

    We report the serendipitous discovery of a supernova (SN) in the nearby radio-galaxy 3C 78. Observations obtained with the STIS spectrograph on board the Hubble Space Telescope show, at a distance of 0.54 arcsec (300 pc) from the galaxy nucleus, a second bright source, not present in previous images. As this source was fortuitously covered by the spectrograph slit its spectrum was obtained and it is characteristic of a Type Ia SN. This SN is closely aligned with the radio-jet of 3C 78. Analys...

  8. 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.

  9. Supernovae and mass extinctions

    Science.gov (United States)

    Vandenbergh, S.

    1994-01-01

    Shklovsky and others have suggested that some of the major extinctions in the geological record might have been triggered by explosions of nearby supernovae. The frequency of such extinction events will depend on the galactic supernova frequency and on the distance up to which a supernova explosion will produce lethal effects upon terrestrial life. In the present note it will be assumed that a killer supernova has to occur so close to Earth that it will be embedded in a young, active, supernova remnant. Such young remnants typically have radii approximately less than 3 pc (1 x 10(exp 19) cm). Larger (more pessimistic?) killer radii have been adopted by Ruderman, Romig, and by Ellis and Schramm. From observations of historical supernovae, van den Bergh finds that core-collapse (types Ib and II) supernovae occur within 4 kpc of the Sun at a rate of 0.2 plus or minus 0.1 per century. Adopting a layer thickness of 0.3 kpc for the galacitc disk, this corresponds to a rate of approximately 1.3 x 10(exp -4) supernovae pc(exp -3) g.y.(exp -1). Including supernovae of type Ia will increase the total supernovae rate to approximately 1.5 x 10(exp -4) supernovae pc(exp -3) g.y.(exp -1). For a lethal radius of R pc the rate of killer events will therefore be 1.7 (R/3)(exp 3) x 10(exp -2) supernovae per g.y. However, a frequency of a few extinctions per g.y. is required to account for the extinctions observed during the phanerozoic. With R (extinction) approximately 3 pc, the galactic supernova frequency is therefore too low by 2 orders of magnitude to account for the major extinctions in the geological record.

  10. 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

  11. The interaction between feedback from active galactic nuclei and supernovae

    NARCIS (Netherlands)

    Booth, C.M.; Schaye, J.

    2013-01-01

    Energetic feedback from supernovae (SNe) and from active galactic nuclei (AGN) are both important processes that are thought to control how much gas is able to condense into galaxies and form stars. We show that although both AGN and SNe suppress star formation, they mutually weaken one another's

  12. Light-curve and spectral properties of ultrastripped core-collapse supernovae leading to binary neutron stars

    Science.gov (United States)

    Moriya, Takashi J.; Mazzali, Paolo A.; Tominaga, Nozomu; Hachinger, Stephan; Blinnikov, Sergei I.; Tauris, Thomas M.; Takahashi, Koh; Tanaka, Masaomi; Langer, Norbert; Podsiadlowski, Philipp

    2017-04-01

    We investigate light-curve and spectral properties of ultrastripped core-collapse supernovae. Ultrastripped supernovae are the explosions of heavily stripped massive stars that lost their envelopes via binary interactions with a compact companion star. They eject only ˜0.1 M⊙ and may be the main way to form double neutron-star systems that eventually merge emitting strong gravitational waves. We follow the evolution of an ultrastripped supernova progenitor until iron core collapse and perform explosive nucleosynthesis calculations. We then synthesize light curves and spectra of ultrastripped supernovae using the nucleosynthesis results and present their expected properties. Ultrastripped supernovae synthesize ˜0.01 M⊙ of radioactive 56Ni, and their typical peak luminosity is around 1042 erg s-1 or -16 mag. Their typical rise time is 5-10 d. Comparing synthesized and observed spectra, we find that SN 2005ek, some of the so-called calcium-rich gap transients, and SN 2010X may be related to ultrastripped supernovae. If these supernovae are actually ultrastripped supernovae, their event rate is expected to be about 1 per cent of core-collapse supernovae. Comparing the double neutron-star merger rate obtained by future gravitational-wave observations and the ultrastripped supernova rate obtained by optical transient surveys identified with our synthesized light-curve and spectral models, we will be able to judge whether ultrastripped supernovae are actually a major contributor to the binary neutron-star population and provide constraints on binary stellar evolution.

  13. Spectroscopic observation of SN2017gkk by NUTS (NOT Un-biased Transient Survey)

    Science.gov (United States)

    Onori, F.; Benetti, S.; Cappellaro, E.; Losada, Illa R.; Gafton, E.; NUTS Collaboration

    2017-09-01

    The Nordic Optical Telescope (NOT) Unbiased Transient Survey (NUTS; ATel #8992) reports the spectroscopic classification of supernova SN2017gkk (=MASTER OT J091344.71762842.5) in host galaxy NGC 2748.

  14. VERY LATE PHOTOMETRY OF SN 2011fe

    Energy Technology Data Exchange (ETDEWEB)

    Kerzendorf, W. E. [Department of Astronomy and Astrophysics, University of Toronto, 50 Saint George Street, Toronto, ON M5S 3H4 (Canada); Taubenberger, S.; Seitenzahl, I. R.; Ruiter, A. J., E-mail: wkerzendorf@gmail.com [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Straße 1, D-85748 Garching (Germany)

    2014-12-01

    The Type Ia supernova SN 2011fe is one of the closest supernovae of the past decades. Due to its proximity and low dust extinction, this object provides a very rare opportunity to study the extremely late time evolution (>900 days) of thermonuclear supernovae. In this Letter, we present our photometric data of SN 2011fe taken at an unprecedented late epoch of ≈930 days with GMOS-N mounted on the Gemini North telescope (g = 23.43 ± 0.28, r = 24.14 ± 0.14, i = 23.91 ± 0.18, and z = 23.90 ± 0.17) to study the energy production and retention in the ejecta of SN 2011fe. Together with previous measurements by other groups, our result suggests that the optical supernova light curve can still be explained by the full thermalization of the decay positrons of {sup 56}Co. This is in spite of theoretical predicted effects (e.g., infrared catastrophe, positron escape, and dust) that advocate a substantial energy redistribution and/or loss via various processes that result in a more rapid dimming at these very late epochs.

  15. STRESS a SN survey at ESO

    Science.gov (United States)

    Botticella, M. T.

    We performed the Southern inTermediate Redshift ESO Supernova Search (STRESS), a survey specifically designed to measure the rate of both SNe Ia and CC SNe, in order to obtain a direct comparison of the high redshift and local rates and to investigate the dependence of the rates on specific galaxy properties, most notably their colour. We found that the type Ia SN rate, at mean redshift z = 0.3, is 0.22+0.10+0.16-0.08-0.14 h270 SNu, while the CC SN rate, at z = 0.21, is 0.82+0.31+0.300.24-0.26 h270 SNu. The quoted errors are the statistical and systematic uncertainties. With respect to the local value, the CC SN rate at z = 0.2 is higher by a factor of ˜ 2, whereas the type Ia SN rate remains almost constant. We also measured the SN rates in the red and blue galaxies and found that the SN Ia rate seems to be constant in galaxies of different colour, whereas the CC SN rate seems to peak in blue galaxies, as in the local Universe. Finally we exploited the link between SFH and SN rates to predict the evolutionary behaviour of the SN rates and compare it with the path indicated by observations.

  16. Could there be a hole in type Ia supernovae?

    Energy Technology Data Exchange (ETDEWEB)

    Kasen, Daniel; Nugent, Peter; Thomas, R.C.; Wang, Lifan

    2004-04-23

    In the favored progenitor scenario, Type Ia supernovae (SNe Ia) arise from a white dwarf accreting material from a non-degenerate companion star. Soon after the white dwarf explodes, the ejected supernova material engulfs the companion star; two-dimensional hydrodynamical simulations by Marietta et al. (2001) show that, in the interaction, the companion star carves out a conical hole of opening angle 30-40 degrees in the supernova ejecta. In this paper we use multi-dimensional Monte Carlo radiative transfer calculations to explore the observable consequences of an ejecta-hole asymmetry. We calculate the variation of the spectrum, luminosity, and polarization with viewing angle for the aspherical supernova near maximum light. We find that the supernova looks normal from almost all viewing angles except when one looks almost directly down the hole. In the latter case, one sees into the deeper, hotter layers of ejecta. The supernova is relatively brighter and has a peculiar spectrum characterized by more highly ionized species, weaker absorption features, and lower absorption velocities. The spectrum viewed down the hole is comparable to the class of SN 1991T-like supernovae. We consider how the ejecta-hole asymmetry may explain the current spectropolarimetric observations of SNe Ia, and suggest a few observational signatures of the geometry. Finally, we discuss the variety currently seen in observed SNe Ia and how an ejecta-hole asymmetry may fit in as one of several possible sources of diversity.

  17. Outflows from Magnetorotational Supernovae

    OpenAIRE

    Moiseenko, S. G.; Bisnovatyi-Kogan, G. S.

    2008-01-01

    We discuss results of 2D simulations of magnetorotational(MR) mechanism of core collapse supernova explosions. Due to the nonuniform collapse the collapsed core rotates differentially. In the presence of initial poloidal magnetic field its toroidal component appears and grows with time. Increased magnetic pressure leads to foramtion of compression wave which moves outwards. It transforms into the fast MHD shock wave (supernova shock wave). The shape of the MR supernova explosion qualitatively...

  18. 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.

  19. The historical supernovae

    CERN Document Server

    Clark, David H

    1977-01-01

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

  20. Constraints on high-energy neutrino emission from SN 2008D

    NARCIS (Netherlands)

    Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Adams, J.; Aguilar, J.A.; Ahlers, M.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S.W.; Bay, R.; Alba, J.L.B.; Beattie, K.; Beatty, J.J.; Bechet, S.; Becker, J.K.; Becker, K.H.; Benabderrahmane, M.L.; BenZvi, S.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D.Z.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D.J.; Bohm, C.; Bose, D.; Boser, S.; Botner, O.; Braun, J.; Buitink, S.; Carson, M.; Chirkin, D.; Christy, B.; Clem, J.; Clevermann, F.; Cohen, S.; Colnard, C.; Cowen, D.F.; D'Agostino, M.V.; Danninger, M.; Davis, J.C.; Clercq, C. De; Demirors, L.; Depaepe, O.; Descamps, F.; Desiati, P.; Vries-Uiterweerd, G. de; DeYoung, T.; Diaz-Velez, J.C.; Dierckxsens, M.; Dreyer, J.; Dumm, J.P.; Duvoort, M.R.; Ehrlich, R.; Eisch, J.; Ellsworth, R.W.; Engdegard, O.; Euler, S.; Evenson, P.A.; Fadiran, O.; Fazely, A.R.; Fedynitch, A.; Feusels, T.; Filimonov, K.; Finley, C.; Foerster, M.M.; Fox, B.D.; Franckowiak, A.; Franke, R.; Gaisser, T.K.; Gallagher, J.; Geisler, M.; Gerhardt, L.; Gladstone, L.; Glusenkamp, T.; Goldschmidt, A.; Goodman, J.A.; Grant, D.; Griesel, T.; Gross, A.; Grullon, S.; Gurtner, M.; Ha, C.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Helbing, K.; Herquet, P.; Hickford, S.; Hill, G.C.; Hoffman, K.D.; Homeier, A.; Hoshina, K.; Lafebre, S.J.

    2011-01-01

    SN 2008D, a core collapse supernova at a distance of 27 Mpc, was serendipitously discovered by the Swift satellite through an associated X-ray flash. Core collapse supernovae have been observed in association with long gamma-ray bursts and X-ray flashes and a physical connection is widely assumed.

  1. Hydrodynamic ablation of protoplanetary discs via supernovae

    Science.gov (United States)

    Close, J. L.; Pittard, J. M.

    2017-07-01

    We present three-dimensional simulations of a protoplanetary disc subject to the effect of a nearby (0.3 pc distant) supernova (SN), using a time-dependent flow from a one-dimensional numerical model of the supernova remnant (SNR), in addition to constant peak ram pressure simulations. Simulations are performed for a variety of disc masses and inclination angles. We find disc mass-loss rates that are typically 10-7-10-6 M⊙ yr-1 (but they peak near 10-5 M⊙ yr-1 during the 'instantaneous' stripping phase) and are sustained for around 200 yr. Inclination angle has little effect on the mass-loss unless the disc is close to edge-on. Inclined discs also strip asymmetrically with the trailing edge ablating more easily. Since the interaction lasts less than one outer rotation period, there is not enough time for the disc to restore its symmetry, leaving the disc asymmetrical after the flow has passed. Of the low-mass discs considered, only the edge-on disc is able to survive interaction with the SNR (with 50 per cent of its initial mass remaining). At the end of the simulations, discs that survive contain fractional masses of SN material up to 5 × 10-6. This is too low to explain the abundance of short-lived radionuclides in the early Solar system, but a larger disc and the inclusion of radiative cooling might allow the disc to capture a higher fraction of SN material.

  2. The 20th anniversary of SN1987A

    Science.gov (United States)

    Suzuki, A.

    2008-07-01

    Observation of a neutrino burst from the supernova, SN1987A opened a new window of observational astronomy by neutrinos. And the history showed that the SN1987A neutrino burst observation was the vanguard of successive discoveries of neutrino properties by Super-Kamiokande, SNO, K2K, KamLAND and so on. On the occasion of the SN1987A 20th anniversary, the backstage story up to the discovery of the SN1987A neutrino bursts is summarized, tracing the Kamiokande log-note and including the IMB, LSD and Baksan data.

  3. 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.

  4. Host Galaxy Identification for Supernova Surveys

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Ravi R.; Kuhlmann, Steve; Kovacs, Eve; Spinka, Harold; Kessler, Richard; Goldstein, Daniel A.; Liotine, Camille; Pomian, Katarzyna; D’Andrea, Chris B.; Sullivan, Mark; Carretero, Jorge; Castander, Francisco J.; Nichol, Robert C.; Finley, David A.; Fischer, John A.; Foley, Ryan J.; Kim, Alex G.; Papadopoulos, Andreas; Sako, Masao; Scolnic, Daniel M.; Smith, Mathew; Tucker, Brad E.; Uddin, Syed; Wolf, Rachel C.; Yuan, Fang; Abbott, Tim M. C.; Abdalla, Filipe B.; Benoit-Lévy, Aurélien; Bertin, Emmanuel; Brooks, David; Rosell, Aurelio Carnero; Kind, Matias Carrasco; Cunha, Carlos E.; Costa, Luiz N. da; Desai, Shantanu; Doel, Peter; Eifler, Tim F.; Evrard, August E.; Flaugher, Brenna; Fosalba, Pablo; Gaztañaga, Enrique; Gruen, Daniel; Gruendl, Robert; James, David J.; Kuehn, Kyler; Kuropatkin, Nikolay; Maia, Marcio A. G.; Marshall, Jennifer L.; Miquel, Ramon; Plazas, Andrés A.; Romer, A. Kathy; Sánchez, Eusebio; Schubnell, Michael; Sevilla-Noarbe, Ignacio; Sobreira, Flávia; Suchyta, Eric; Swanson, Molly E. C.; Tarle, Gregory; Walker, Alistair R.; Wester, William

    2016-11-08

    Host galaxy identification is a crucial step for modern supernova (SN) surveys such as the Dark Energy Survey (DES) and the Large Synoptic Survey Telescope (LSST), which will discover SNe by the thousands. Spectroscopic resources are limited, so in the absence of real-time SN spectra these surveys must rely on host galaxy spectra to obtain accurate redshifts for the Hubble diagram and to improve photometric classification of SNe. In addition, SN luminosities are known to correlate with host-galaxy properties. Therefore, reliable identification of host galaxies is essential for cosmology and SN science. We simulate SN events and their locations within their host galaxies to develop and test methods for matching SNe to their hosts. We use both real and simulated galaxy catalog data from the Advanced Camera for Surveys General Catalog and MICECATv2.0, respectively. We also incorporate "hostless" SNe residing in undetected faint hosts into our analysis, with an assumed hostless rate of 5%. Our fully automated algorithm is run on catalog data and matches SNe to their hosts with 91% accuracy. We find that including a machine learning component, run after the initial matching algorithm, improves the accuracy (purity) of the matching to 97% with a 2% cost in efficiency (true positive rate). Although the exact results are dependent on the details of the survey and the galaxy catalogs used, the method of identifying host galaxies we outline here can be applied to any transient survey.

  5. Turning Gravitationally Lensed Supernovae into Cosmological Probes

    Science.gov (United States)

    Roberts-Pierel, Justin

    2017-08-01

    Recent HST observations have been critically important for twolandmark discoveries of gravitationally lensed supernovae: the firstmultiply-imaged SN, Refsdal, and the first Type Ia SN resolved intomultiple images, SN iPTF16geu. Fitting the multiple light curves ofsuch objects can deliver measurements of the lensing time delays,which in turn provide precise tests of lens models or uniqueconstraints on the Hubble constant and other cosmological parameters.For both of these SNe, initial constraints on the time delays havebeen limited by the need to account for subtle microlensingeffects. We will perform a complete reanalysis of both SN Refsdal andSN iPTF16geu, in order to refine estimates of their lensingmagnifications and time delays. Our work will improve upon previousefforts by revising the data processing and photometry, and includingthe significant yet previously ignored effects ofmicrolensing. Additionally, we will develop a publicly availablesoftware package in the course of this work, optimized specificallyfor multiply-imaged SNe. This software will be an important tool inthe next decade, supporting precise time delay measurements of tens tohundreds of lensed SNe to be found with LSST and WFIRST.

  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. Comparative Analysis of Peculiar Type Ia 1991bg-like Supernovae Spectra

    Science.gov (United States)

    Doull, Brandon A.; Baron, E.

    2011-07-01

    Spectroscopic analyses of Type Ia supernovae have shown that there exist four spectroscopic groups—cool, broad line, shallow silicon, and core normal—defined by the widths of the Si II features λ5972 and λ6355. The 1991bg-like SNe Ia are classified as “cool.” Cool SNe Ia are dim, undergo a rapid decline in luminosity, and produce significantly less 56Ni than normal Type Ia supernovae. They also have an unusually deep and wide trough in their spectra at around 4200 Å and a relatively strong Si II absorption attributed to λ5972. We examine the spectra of supernova (SN) 1991bg and the cool SN 1997cn, SN 1999by, and SN 2005bl using the highly parameterized synthetic spectrum code SYNOW, and we find general agreement with similar spectroscopic studies. Our analysis reveals that this group of supernovae is fairly homogeneous, with many of the blue spectral features well fit by Fe II. The nature of the spectroscopic commonalities and the variations in the class are discussed. Finally, we examine intermediates such as SN 2004eo and discuss the spectroscopic subgroup distribution of Type Ia supernovae.

  8. Matching Supernovae to Galaxies

    Science.gov (United States)

    Kohler, Susanna

    2016-12-01

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

  9. Supernova hydrodynamics on the Omega laser

    Science.gov (United States)

    Drake, R. P.; Keiter, P.; Korreck, K. E.; Dannenberg, K. K.; Robey, H. A.; Perry, T. S.; Kane, J. O.; Remington, B. A.; Wallace, R. J.; Hurricane, O. A.; Ryutov, D. D.; Knauer, J.; Teyssier, R.; Calder, A.; Rosner, R.; Fryxell, B.; Arnett, D.; Zhang, Y.; Glimm, J.; Turner, N.; Stone, J.; McCray, R.; Grove, J.

    2001-10-01

    Our experiments study mechanisms that affect the evolution of supernovae, supernova remnants, and related systems. These experiments are designed to be well scaled from astrophysical systems to the laboratory. This overview of our work will highlight our most recent results. Our work is motivated by the specific fact that numerical simulations have proven unable to reproduce certain aspects of astrophysical observations, and by the general need to provide experimental tests of modeling of hydrodynamic and radiation-hydrodynamic systems. The experiments use the Omega Laser at the Lab. for Laser Energetics, Univ. of Rochester. We have recently explored the comparison of 2D and 3D systems, the comparison of single mode and multimode systems, and the production and diagnosis of a radiative-precursor shock.

  10. Pre-supernova properties of progenitors detected by HST

    Science.gov (United States)

    Fuller, Jim

    2017-08-01

    HST has provided essential data on the connection between core-collapse supernovae (SNe) and their massive star progenitors, both through precise post-explosion localization of nearby SNe, and by identification of progenitor stars in pre-explosion HST images. However, mounting evidence suggests that many SN progenitors exhibit outbursts and/or enhanced mass loss in the years preceding the SN, potentially affecting the progenitor properties measured by HST. Inferring progenitor characteristics such as stellar mass thus requires a better theoretical understanding of the pre-SN stellar evolution. A compelling mechanism for pre-SN outbursts is energy transport via gravity/acoustic waves within massive star SN progenitors. We propose to quantify the observable effects of wave-driven outbursts and mass loss in the final years of massive star lives using stellar evolution calculations incorporating wave energy transport. Our models will make predictions for progenitor luminosity in HST bands as a function of stellar mass and time before SN explosion. We will also model the SN light curves and spectra of stars with wave energy transport, which we can compare with SN observations to assert whether wave heating operated in the progenitors detected by HST. We will then revisit the interpretation of HST progenitor data and make predictions for future SN progenitor detections by HST.

  11. Structures of tin cluster cations Sn3(+) to Sn15(+).

    Science.gov (United States)

    Drebov, Nedko; Oger, Esther; Rapps, Thomas; Kelting, Rebecca; Schooss, Detlef; Weis, Patrick; Kappes, Manfred M; Ahlrichs, Reinhart

    2010-12-14

    We employ a combination of ion mobility measurements and an unbiased systematic structure search with density functional theory methods to study structure and energetics of gas phase tin cluster cations, Sn(n)(+), in the range of n = 3-15. For Sn(13)(+) we also carry out trapped ion electron diffraction measurements to ascertain the results obtained by the other procedures. The structures for the smaller systems are most easily described by idealized point group symmetries, although they are all Jahn-Teller distorted: D(3h) (trigonal bipyramid), D(4h) (octahedron), D(5h) (pentagonal bipyramid) for n = 5, 6, and 7. For the larger systems we find capped D(5h) for Sn(8)(+) and Sn(9)(+), D(3h) (tricapped trigonal prism) and D(4d) (bicapped squared antiprism) plus adatoms for n = 10, 11, 14, and 15. A centered icosahedron with a peripheral atom removed is the dominant motif in Sn(12)(+). For Sn(13)(+) the calculations predict a family of virtually isoenergetic isomers, an icosahedron and slightly distorted icosahedra, which are about 0.25 eV below two C(1) structures. The experiments indicate the presence of two structures, one from the I(h) family and a prolate C(1) isomer based on fused deltahedral moieties.

  12. Evolution of Supernova Remnants

    Science.gov (United States)

    Arbutina, B.

    2017-12-01

    This book, both a monograph and a graduate textbook, is based on my original research and partly on the materials prepared earlier for the 2007 and 2008 IARS Astrophysics Summer School in Istanbul, AstroMundus course 'Supernovae and Their Remnants' that was held for the first time in 2011 at the Department of Astronomy, Faculty of Mathematics, University of Belgrade, and a graduate course 'Evolution of Supernova Remnants' that I teach at the aforementioned university. The first part Supernovae (introduction, thermonuclear supernovae, core-collapse supernovae) provides introductory information and explains the classification and physics of supernova explosions, while the second part Supernova remnants (introduction, shock waves, cosmic rays and particle acceleration, magnetic fields, synchrotron radiation, hydrodynamic and radio evolution of supernova remnants), which is the field I work in, is more detailed in scope i.e. technical/mathematical. Special attention is paid to details of mathematical derivations that often cannot be found in original works or available literature. Therefore, I believe it can be useful to both, graduate students and researchers interested in the field.

  13. The Stellar Origins of Supernovae

    Science.gov (United States)

    Van Dyk, Schulyer

    2017-08-01

    Supernovae (SNe) have a profound effect on galaxies and have been used as precise cosmological probes, resulting in the Nobel-distinguished discovery of the accelerating Universe. They are clearly very important events deserving of intense study. Yet, even with over 10000 classified SNe, we know relatively little about the stars which give rise to these powerful explosions. The main limitation has been the lack of spatial resolution in pre-SN imaging data. However, since 1999 our team has been at the vanguard of directly identifying SN progenitor stars in HST images. From this exciting line of study, the trends from 15 detections for Type II-Plateau SNe appear to be red supergiant progenitors of relatively low mass (8 to 17 Msun) - although this upper mass limit still requires testing - and warmer, envelope-stripped supergiant progenitors for 5 Type IIb SNe. Additionally, evidence is accumulating that some Type II-narrow SNe may arise from exploding stars in a luminous blue variable phase. However, the nature of the progenitors of Type Ib/c SNe, a subset of which are associated with gamma-ray bursts, still remains ambiguous. Furthermore, we continue in the embarrassing situation that we still do not yet know which progenitor systems explode as Type Ia SNe, which are being used for precision cosmology. In Cycles 16, 17, and 20 through 24 we have had great success with our approved ToO programs. As of this proposal deadline, we have already triggered on SN 2016jbu with our Cycle 24 program. We therefore propose to continue this project in Cycles 25 and 26, to determine the identities of the progenitors of 8 SNe within about 20 Mpc through ToO observations using WFC3/UVIS.

  14. Supernovae and supernova remnants at high energies

    Science.gov (United States)

    Chevalier, Roger A.

    1990-01-01

    The physical phenomena that are observable with X- and gamma-ray observations of supernovae are discussed with respect to possible high-energy astrophysics experiments. Prompt photospheric emission and its echo are discussed, supernova radioactivity and neutron star effects are examined, and circumstellar and interstellar interaction are reviewed. The primary uncertainties are found to be the hardening of the spectrum by non-LTE effects and the amount of absorption of the radiation from the initial soft X-ray burst. The radioactivity in supernovae is theorized to lead to gamma-ray lines and continuum emission unless the event is low-mass type II. Gamma-ray observations are proposed to examine the efficiency of particle acceleration, and high-resolution spectroscopy can provide data regarding ionization, temperature, composition, and velocities of the X-ray-emitting gas.

  15. Dependence on supernovae light-curve processing in void models

    Energy Technology Data Exchange (ETDEWEB)

    Bengochea, Gabriel R., E-mail: gabriel@iafe.uba.ar [Instituto de Astronomía y Física del Espacio (IAFE), UBA-CONICET, CC 67, Suc. 28, 1428 Buenos Aires (Argentina); De Rossi, Maria E., E-mail: derossi@iafe.uba.ar [Instituto de Astronomía y Física del Espacio (IAFE), UBA-CONICET, CC 67, Suc. 28, 1428 Buenos Aires (Argentina); Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina)

    2014-06-02

    In this work, we show that when supernova Ia (SN Ia) data sets are used to put constraints on the free parameters of inhomogeneous models, certain extra information regarding the light-curve fitter used in the supernovae Ia luminosity fluxes processing should be taken into account. We found that the size of the void as well as other parameters of these models might be suffering extra degenerations or additional systematic errors due to the fitter. A recent proposal to relieve the tension between the results from Planck satellite and SNe Ia is re-analyzed in the framework of these subjects.

  16. A SEARCH FOR NEW CANDIDATE SUPER-CHANDRASEKHAR-MASS TYPE Ia SUPERNOVAE IN THE NEARBY SUPERNOVA FACTORY DATA SET

    Energy Technology Data Exchange (ETDEWEB)

    Scalzo, R. [Research School of Astronomy and Astrophysics, Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611 (Australia); Aldering, G.; Aragon, C.; Bailey, S.; Childress, M.; Fakhouri, H. K.; Hsiao, E. Y. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [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, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Institut de Physique Nucleaire, 43 Boulevard du 11 Novembre 1918, 69622 Villeurbanne Cedex (France); Nugent, P., E-mail: rscalzo@mso.anu.edu.au [Computational Cosmology Center, Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road MS 50B-4206, Berkeley, CA 94720 (United States); Collaboration: Nearby Supernova Factory; and others

    2012-09-20

    We present optical photometry and spectroscopy of five Type Ia supernovae discovered by the Nearby Supernova Factory selected to be spectroscopic analogs of the candidate super-Chandrasekhar-mass events SN 2003fg and SN 2007if. Their spectra are characterized by hot, highly ionized photospheres near maximum light, for which SN 1991T supplies the best phase coverage among available close spectral templates. Like SN 2007if, these supernovae are overluminous (-19.5 < M{sub V} < -20) and the velocity of the Si II {lambda}6355 absorption minimum is consistent with being constant in time from phases as early as a week before, and up to two weeks after, B-band maximum light. We interpret the velocity plateaus as evidence for a reverse-shock shell in the ejecta formed by interaction at early times with a compact envelope of surrounding material, as might be expected for SNe resulting from the mergers of two white dwarfs. We use the bolometric light curves and line velocity evolution of these SNe to estimate important parameters of the progenitor systems, including {sup 56}Ni mass, total progenitor mass, and masses of shells and surrounding carbon/oxygen envelopes. We find that the reconstructed total progenitor mass distribution of the events (including SN 2007if) is bounded from below by the Chandrasekhar mass, with SN 2007if being the most massive. We discuss the relationship of these events to the emerging class of super-Chandrasekhar-mass SNe Ia, estimate the relative rates, compare the mass distribution to that expected for double-degenerate SN Ia progenitors from population synthesis, and consider implications for future cosmological Hubble diagrams.

  17. The direct identification of core-collapse supernova progenitors

    Science.gov (United States)

    Van Dyk, Schuyler D.

    2017-09-01

    To place core-collapse supernovae (SNe) in context with the evolution of massive stars, it is necessary to determine their stellar origins. I describe the direct identification of SN progenitors in existing pre-explosion images, particularly those obtained through serendipitous imaging of nearby galaxies by the Hubble Space Telescope. I comment on specific cases representing the various core-collapse SN types. Establishing the astrometric coincidence of a SN with its putative progenitor is relatively straightforward. One merely needs a comparably high-resolution image of the SN itself and its stellar environment to perform this matching. The interpretation of these results, though, is far more complicated and fraught with larger uncertainties, including assumptions of the distance to and the extinction of the SN, as well as the metallicity of the SN environment. Furthermore, existing theoretical stellar evolutionary tracks exhibit significant variations one from the next. Nonetheless, it appears fairly certain that Type II-P (plateau) SNe arise from massive stars in the red supergiant phase. Many of the known cases are associated with subluminous Type II-P events. The progenitors of Type II-L (linear) SNe are less established. Among the stripped-envelope SNe, there are now a number of examples of cool, but not red, supergiants (presumably in binaries) as Type IIb progenitors. We appear now finally to have an identified progenitor of a Type Ib SN, but no known example yet for a Type Ic. The connection has been made between some Type IIn SNe and progenitor stars in a luminous blue variable phase, but that link is still thin, based on direct identifications. Finally, I also describe the need to revisit the SN site, long after the SN has faded, to confirm the progenitor identification through the star's disappearance and potentially to detect a putative binary companion that may have survived the explosion. This article is part of the themed issue 'Bridging the gap

  18. The evolution of red supergiants to supernovae

    Science.gov (United States)

    Beasor, Emma R.; Davies, Ben

    2017-11-01

    With red supergiants (RSGs) predicted to end their lives as Type IIP core collapse supernova (CCSN), their behaviour before explosion needs to be fully understood. Mass loss rates govern RSG evolution towards SN and have strong implications on the appearance of the resulting explosion. To study how the mass-loss rates change with the evolution of the star, we have measured the amount of circumstellar material around 19 RSGs in a coeval cluster. Our study has shown that mass loss rates ramp up throughout the lifetime of an RSG, with more evolved stars having mass loss rates a factor of 40 higher than early stage RSGs. Interestingly, we have also found evidence for an increase in circumstellar extinction throughout the RSG lifetime, meaning the most evolved stars are most severely affected. We find that, were the most evolved RSGs in NGC2100 to go SN, this extra extinction would cause the progenitor's initial mass to be underestimated by up to 9M⊙.

  19. Bayesian Single-Epoch Photometric Classification of Supernovae

    Science.gov (United States)

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

    2007-09-01

    Ongoing supernova (SN) surveys find hundreds of candidates that require confirmation for their various uses. Traditional classification based on follow-up spectroscopy of all candidates is virtually impossible for these large samples. The use of Type Ia SNe as standard candles is at an evolved stage that requires pure, uncontaminated samples. However, other SN survey applications, such as measuring cosmic SN rates, could benefit from a classification of SNe on a statistical basis, rather than case by case. With this objective in mind, we have developed the SN-ABC, an automatic Bayesian classifying algorithm for supernovae. We rely solely on single-epoch multiband photometry and host-galaxy (photometric) redshift information to sort SN candidates into the two major types, Ia and core-collapse supernovae. We test the SN-ABC performance on published samples of SNe from the Supernova Legacy Survey (SNLS) and GOODS projects that have both broadband photometry and spectroscopic classification (so the true type is known). The SN-ABC correctly classifies up to 97% (85%) of the Type Ia (II-P) SNe in SNLS, and similar fractions of the GOODS SNe, depending on photometric redshift quality. Using simulations with large artificial samples, we find similarly high success fractions for Types Ia and II-P, and reasonable (~75%) success rates in classifying Type Ibc SNe as core-collapse. Type IIn SNe, however, are often misclassified as Type Ia. In deep surveys, SNe Ia are best classified at redshifts z gtrsim 0.6 or when near maximum. Core-collapse SNe (other than Type IIn) are best recognized several weeks after maximum, or at z lesssim 0.6. Assuming the SNe are young, as would be the case for rolling surveys, the success fractions improve by a degree dependent on the type and redshift. The fractional contamination of a single-epoch photometrically selected sample of SNe Ia by core-collapse SNe varies between less than 10% and as much as 30%, depending on the intrinsic fraction and

  20. Nearby supernova host galaxies from the CALIFA Survey. I. Sample, data analysis, and correlation to star-forming regions

    NARCIS (Netherlands)

    Galbany, L.; Stanishev, V.; Mourão, A. M.; Rodrigues, M.; Flores, H.; García-Benito, R.; Mast, D.; Mendoza, M. A.; Sánchez, S. F.; Badenes, C.; Barrera-Ballesteros, J.; Bland-Hawthorn, J.; Falcón-Barroso, J.; García-Lorenzo, B.; Gomes, J. M.; González Delgado, R. M.; Kehrig, C.; Lyubenova, M.; López-Sánchez, A. R.; de Lorenzo-Cáceres, A.; Marino, R. A.; Meidt, S.; Mollá, M.; Papaderos, P.; Pérez-Torres, M. A.; Rosales-Ortega, F. F.; van de Ven, G.

    2014-01-01

    We use optical integral field spectroscopy (IFS) of nearby supernova (SN) host galaxies (0.005 2.4 Gyr, respectively) than the massive SN Ia hosts (0.04%, 2.01%, and 97.95% in these intervals). We estimate that the low-mass galaxies produce ten times fewer SNe Ia and three times fewer CC SNe than

  1. 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...

  2. Asiago Supernova classification program: Blowing out the first two hundred candles

    Science.gov (United States)

    Tomasella , L.; Benetti, S.; Cappellaro, E.; Pastorello, A.; Turatto, M.; Barbon, R.; Elias-Rosa, N.; Harutyunyan, A.; Ochner, P.; Tartaglia, L.; Valenti, S.

    2014-10-01

    We present the compilation of the first 221 supernovae classified during the Asiago Classification Program (ACP). The details of transients classification and the preliminarily reduced spectra, in fits format, are immediately posted on the Padova-Asiago SN group web site. The achieved performances for the first 2 years of the ACP are analysed, showing that half of all our classifications were made within 5 days from transient detection. The distribution of the supernova types of this sample resembles the distribution of the general list of all the supernovae listed in the Asiago SN catalog (ASNC, Barbon et al. 1999). Finally, we use our subsample of 78 core-collapse supernovae, for which we retrieve the host-galaxy morphology and r-band absolute magnitudes, to study the observed subtype distribution in dwarf compared to giant galaxies. This ongoing program will give its contribution to the classification of the large number of transients that will be soon delivered by the Gaia mission.

  3. SEARCH FOR GRAVITATIONAL WAVES FROM SUPERNOVAE AND LONG GRBS

    Directory of Open Access Journals (Sweden)

    Maurice H.P.M. van Putten

    2013-12-01

    Full Text Available We report on evidence for black hole spindown in the light curves of the BATSE catalogue of 1491 long GRBs by application of matched filtering. This observation points to a strong interaction of the black hole with surrounding high density matter at the ISCO, inducing non-axisymmetric instabilities sustained by cooling in gravitational wave emission. Opportunities for LIGO-Virgo and the recently funded KAGRA experiments are highlighted, for long GRBs with and without supernovae and for hyper-energetic core-collapse supernovae within a distance of about 35Mpc in the Local Universe.

  4. Nonthermal emission of SN 1987A

    Science.gov (United States)

    Berezhko, Evgeny; Ksenofontov, Leonid; Voelk, Heinrich

    A nonlinear kinetic theory of cosmic-ray acceleration in supernova remnants is employed to investigate the properties of the remnant SN 1987A. Recent observational data in radio and X-ray is used to constrain a set of model parameters. The spectrum of gamma-ray emission and its behavior in time is calculated and compared with sensitivities of the modern ground-based gamma-ray experiments.

  5. ASASSN-16mv: Discovery of A Probable Supernova in ESO 563- G 035

    Science.gov (United States)

    Nicholls, B.; Shields, J.; Stanek, K. Z.; Kochanek, C. S.; Brown, J. S.; Holoien, T. W.-S.; Shappee, B. J.; Prieto, J. L.; Bersier, D.; Dong, Subo; Bose, S.; Chen, Ping; Brimacombe, J.; Stone, G.; Post, R. S.; Masi, G.; Koff, R. A.

    2016-11-01

    During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from the quadruple 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy ESO 563- G 035. ASASSN-16mv was discovered in images obtained on UT 2016-11-04.31 at V 16.8 mag. We also detect the object in images obtained on several previous epochs.

  6. Multi-wavelength observations of the enduring type IIn Supernovae 2005ip and 2006jd

    DEFF Research Database (Denmark)

    Stritzinger, Maximilian; Taddia, Francesco; Fransson, Claes

    2012-01-01

    extend from UV to mid-infrared wavelengths, and like SN 2005ip, are compared to reported X-ray measurements to understand the nature of the progenitor. Both objects display a number of similarities with the 1988Z-like subclass of SN IIn including (1) remarkably similar early-and late-phase optical......We present an observational study of the Type IIn supernovae (SNe IIn) 2005ip and 2006jd. Broadband UV, optical, and near-IR photometry, and visual-wavelength spectroscopy of SN 2005ip complement and extend upon published observations to 6.5 years past discovery. Our observations of SN 2006jd...

  7. Type Ia supernovae yielding distances with 3-4% precision

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Patrick L. [Univ. of California, Berkeley, CA (United States); Filippenko, Alexei V. [Univ. of California, Berkeley, CA (United States); Burke, David L. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hicken, Malcolm [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Ganeshalingam, Mohan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zheng, Weikang [Univ. of California, Berkeley, CA (United States)

    2015-01-26

    The luminosities of Type Ia supernovae (SN), the thermonuclear explosions of white dwarf stars, vary systematically with their intrinsic color and light-curve decline rate. These relationships have been used to calibrate their luminosities to within ~0.14–0.20 mag from broadband optical light curves, yielding individual distances accurate to ~7–10%. Here we identify a subset of SN Ia that erupt in environments having high ultraviolet surface brightness and star-formation surface density. When we apply a steep model extinction law, these SN can be calibrated to within ~0.065–0.075 mag, corresponding to ~3–4% in distance — the best yet with SN Ia by a substantial margin. The small scatter suggests that variations in only one or two progenitor properties account for their light-curve-width/color/luminosity relation.

  8. Supernova Neutrino Physics with Xenon Dark Matter Detectors

    Science.gov (United States)

    Reichard, Shayne; Lang, Rafael F.; McCabe, Christopher; Selvi, Marco; Tamborra, Irene

    2017-09-01

    The dark matter experiment XENON1T is operational and sensitive to all flavors of neutrinos emitted from a supernova. We show that the proportional scintillation signal (S2) allows for a clear observation of the neutrino signal and guarantees a particularly low energy threshold, while the backgrounds are rendered negligible during the SN burst. XENON1T (XENONnT and LZ; DARWIN) will be sensitive to a SN burst up to 25 (40; 70) kpc from Earth at a significance of more than 5σ, observing approximately 35 (123; 704) events from a 27 M ⊙ SN progenitor at 10 kpc. Moreover, it will be possible to measure the average neutrino energy of all flavors, to constrain the total explosion energy, and to reconstruct the SN neutrino light curve. Our results suggest that a large xenon detector such as DARWIN will be competitive with dedicated neutrino telescopes, while providing complementary information that is not otherwise accessible.

  9. XMM Observations of X-Ray Emission from Supernovae

    Science.gov (United States)

    Immler, Stefan; Lewin, Walter

    2003-01-01

    Of the six proposed targets, only one observation was performed. The observation resulted in a 28ks observation of SN 1998S. At the time of writing the proposal, our target list only contained previously unknown X-ray supernovae. Between submission of the proposal and the actual observation, a Chandra DDT observation resulted in the detection of SN 1998S. Since SN 1998S was observed with Chandra five times before the XMM-Newton observation was made, the data did not yield enough new information to warrant a separate SN 1998S publication. The key science results of that observation were presented in a review article (by Immler and Lewin); the results were also presented at two conferences.

  10. TYPE Ia SUPERNOVA CARBON FOOTPRINTS

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-12-10

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

  11. 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....

  12. 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.; hide

    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.

  13. The Supernova associated with GRB 030329

    CERN Document Server

    Dado, S; De Rújula, Alvaro; Dado, Shlomo; Dar, Arnon; Rujula, Alvaro De

    2003-01-01

    The relative proximity of the recent gamma ray burst (GRB) 030329 resulted in a large gamma-ray fluence and in the brightest-ever afterglow (AG), hours after the burst, in the radio, optical and X-ray bands, permitting precise AG measurements, sensitive tests of models and an excellent occasion to investigate the association of GRBs with supernovae (SNe). The Cannonball (CB) model provides a good, simple and universal description of all AGs of GRBs of known redshift, so that it is straightforward to use it to predict what the expected SN signatures are. In the case of GRB 030329, 10 days after burst the AG should begin to reveal the lightcurve, spectrum and polarization of an underlying SN --akin to SN1998bw-- which will peak in the NIR/optical band around day 15. These effects will be easily observable if indeed SN1998bw is a good ``standard candle'' for GRB-associated SNe and if the so far unknown extinction in the host galaxy is not too large.

  14. Mapping the Supernova-Rich Fireworks Galaxy NGC 6946

    Science.gov (United States)

    Patton, Locke; Levesque, Emily

    2018-01-01

    Supernovae (SNe) are the spectacularly violent deaths of evolved young massive stars, which expel a shock wave into the intergalactic medium that in turn can spark star formation and disperse heavy elements into their host galaxy. While a SN event can be classified by its spectral signature, determining the nature of a SN progenitor depends upon chance photometry taken prior to the event. By turning to the study of SN host environments and their surrounding interstellar medium within the unique and rare population of galaxies that have hosted three or more SN events within the last century, we are granted the opportunity to study the locations and environmental properties of stellar populations prone to supernova progenitor production. Using moderate-resolution optical slit spectra taken with the Apache Point Observatory 3.5m DIS spectrograph, our goal is to map metallicity, ionization parameter, and star formation rates using emission line diagnostic ratios across each SN-rich galaxy. Dubbed the “Fireworks Galaxy” at a distance of 5.6 ± 1.5 Mpc, NGC 6946 is of particular interest as it has uniquely produced ten core-collapse supernovae (CCSNe) and several other massive star transients within the last century. We present spatially-resolved metallicity and star formation rate (SFR) maps of NGC 6946, tracing fifty-five slit orientations which span the face of the galaxy and cover all CCSN host sites. Future work will include both stellar population synthesis modelling to determine stellar populations, ages, and SFR histories in NGC 6946 and a further expansion of this analysis to the other SN-rich host galaxies in our sample.

  15. Observational Evidence for High Neutronization in Supernova Remnants: Implications for Type Ia Supernova Progenitors

    Science.gov (United States)

    Martínez-Rodríguez, Héctor; Badenes, Carles; Yamaguchi, Hiroya; Bravo, Eduardo; Timmes, F. X.; Miles, Broxton J.; Townsley, Dean M.; Piro, Anthony L.; Mori, Hideyuki; Andrews, Brett; Park, Sangwook

    2017-07-01

    The physical process whereby a carbon-oxygen white dwarf explodes as a Type Ia supernova (SN Ia) remains highly uncertain. The degree of neutronization in SN Ia ejecta holds clues to this process because it depends on the mass and the metallicity of the stellar progenitor, and on the thermodynamic history prior to the explosion. We report on a new method to determine ejecta neutronization using Ca and S lines in the X-ray spectra of Type Ia supernova remnants (SNRs). Applying this method to Suzaku data of Tycho, Kepler, 3C 397, and G337.2-0.7 in the Milky Way, and N103B in the Large Magellanic Cloud, we find that the neutronization of the ejecta in N103B is comparable to that of Tycho and Kepler, which suggests that progenitor metallicity is not the only source of neutronization in SNe Ia. We then use a grid of SN Ia explosion models to infer the metallicities of the stellar progenitors of our SNRs. The implied metallicities of 3C 397, G337.2-0.7, and N103B are major outliers compared to the local stellar metallicity distribution functions, indicating that progenitor metallicity can be ruled out as the origin of neutronization for these SNRs. Although the relationship between ejecta neutronization and equivalent progenitor metallicity is subject to uncertainties stemming from the 12C + 16O reaction rate, which affects the Ca/S mass ratio, our main results are not sensitive to these details.

  16. The Effect of Host Galaxies on Type Ia Supernovae in the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Lampeitl, Hubert; /Portsmouth U., ICG; Smith, Mathew; /Cape Town U. /Portsmouth U., ICG; Nichol, Robert C.; /Portsmouth U., ICG; Bassett, Bruce; /South African Astron. Observ. /Cape Town U.; Cinabro, David; /Wayne State U.; Dilday, Benjamin; /Rutgers U., Piscataway; Foley, Ryan J.; /Harvard-Smithsonian Ctr. Astrophys.; Frieman, Joshua A.; /Chicago U. /Fermilab; Garnavich, Peter M.; /Notre Dame U.; Goobar, Ariel; /Stockholm U., OKC; Im, Myungshin; /Seoul Natl. U. /Rutgers U., Piscataway

    2010-05-01

    We present an analysis of the host galaxy dependencies of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We re-discover, to high significance, the strong correlation between host galaxy type and the width of the observed SN light curve, i.e., fainter, quickly declining SNe Ia favor passive host galaxies, while brighter, slowly declining Ia's favor star-forming galaxies. We also find evidence (at between 2 to 3{sigma}) that SNe Ia are {approx_equal} 0.1 magnitudes brighter in passive host galaxies, than in star-forming hosts, after the SN Ia light curves have been standardized using the light curve shape and color variations: This difference in brightness is present in both the SALT2 and MCLS2k2 light curve fitting methodologies. We see evidence for differences in the SN Ia color relationship between passive and star-forming host galaxies, e.g., for the MLCS2k2 technique, we see that SNe Ia in passive hosts favor a dust law of R{sub V} {approx_equal} 1, while SNe Ia in star-forming hosts require R{sub V} {approx} 2. The significance of these trends depends on the range of SN colors considered. We demonstrate that these effects can be parameterized using the stellar mass of the host galaxy (with a confidence of > 4{sigma}) and including this extra parameter provides a better statistical fit to our data. Our results suggest that future cosmological analyses of SN Ia samples should include host galaxy information.

  17. Ambienti Circumstellari ed Interstellari di Supernovae di vario Tipo ed Applicazioni Astrofisiche

    Science.gov (United States)

    Boffi, Francesca R.

    Nella presente tesi vengono studiati gli ambienti circumstellari ed interstellari di supernovae (anche SNe; singolare SN) di vario tipo. In particolare si descrivono alcune applicazioni astrofisiche, relative a questi ambienti, che permettono di desumere informazioni sui sistemi stellari progenitori delle supernovae o di determinare le distanze a tali oggetti. L' emissione radio da supernovae, prodotta nell' ambiente circumstellare ad opera dell'interazione idrodinamica del gas di SN con l' ambiente circostante, puo' essere impiegata come mezzo di indagine del sistema di pre-supernova. In particolare si e' introdotta l'idea che tale emissione possa essere impiegata nel caso delle SNe di tipo Ia come test dei sistemi progenitori di tipo simbiotico. Il test e' stato effettuato sulla SN 1986G, per la quale avevamo ottenuto limiti superiori a lunghezze d'onda radio. Nel caso che un sistema simbiotico sia responsabile di una SN Ia, l'interazione tra l' ejecta e una shell circumstellare origina, in un'epoca molto prossima al massimo di luce, un'emissione radio rivelabile con strumenti tipo Very Large Array. Inoltre l'emissione radio fornisce informazioni circa gli stadi di pre-supernova nel caso di altri tipi di supernova. In questo lavoro di tesi vengono presentati i risultati ottenuti nel caso delle SNe di tipo II 1984E e 1986E. Queste due SNe non mostrano emissione radio: la prima, in prossimita del massimo ottico, stava interagendo con una shell circumstellare prodotta da un episodio di perdita di massa di breve durata in fase di pre-supernova; la seconda, invece e' la prima SN ``vecchia'' ad essere rivelata nell' ottico ma non nel radio (l' oggetto non ha ancora iniziato la fase di supernova remnant ed emette radiazione ottica prodotta ancora per interazione circumstellare). In ambiente circum-interstellare, gli echi di luce, prodotti dallo scattering della luce della supernova ad opera della polvere presente, possono essere utilizzati per determinare le distanze

  18. Unsolved Problems about Supernovae

    OpenAIRE

    Panagia, Nino

    2009-01-01

    A number of unsolved problems and open questions about the nature and the properties of supernovae are identified and briefly discussed. Some suggestions and directions toward possible solutions are also considered.

  19. The Korean 1592--1593 Record of a Guest Star: An `impostor' of the Cassiopeia A Supernova?

    OpenAIRE

    Park, Changbom; Yoon, Sung-Chul; Koo, Bon-Chul

    2016-01-01

    The missing historical record of the Cassiopeia A (Cas A) supernova (SN) event implies a large extinction to the SN, possibly greater than the interstellar extinction to the current SN remnant. Here we investigate the possibility that the guest star that appeared near Cas A in 1592--1593 in Korean history books could have been an `impostor' of the Cas A SN, i.e., a luminous transient that appeared to be a SN but did not destroy the progenitor star, with strong mass loss to have provided extra...

  20. Observations of Supernovae Associated with Gamma-Ray Burst

    Science.gov (United States)

    Volnova, Alina; Pozanenko, Alexei; Pruzhinskaya, Maria; Blinnikov, Sergei; Mazaeva, Elena; Inasaridze, Raguli; Ayvazyan, Vova; Inasaridze, Gulnazi; Reva, Inna; Burkhonov, Otabek; Ehgamberdiev, Shukhrat; Kvaratskhelia, Otari; Rumyantsev, Vasilij; Krugly, Yuri; Klunko, Evgeny; Molotov, Igor

    In this paper, we present an overview of the observational properties of supernovae (SNe) associated with long-duration gamma- ray bursts (GRBs). We summarise the statistics of GRB-SNe physical properties and consider different modelling methods. We report the results of the numerical modelling of the GRB 130702A/SN 2013dx multicolour light curve using a spherically symmetrical multi-group radiation hydrodynamics code STELLA. We have obtained main bolometric parameters of the SN and compare our results with those of analytical modelling.

  1. Massive star evolution: Luminous Blue Variables as unexpected Supernova progenitors

    OpenAIRE

    Groh, Jose H.; Meynet, Georges; Ekström, Sylvia

    2013-01-01

    Stars more massive than about 8 Msun end their lives as a Supernova (SN), an event of fundamental importance Universe-wide. Theoretically, these stars have been expected to be either at the red supergiant, blue supergiant, or Wolf-Rayet stage before the explosion. We performed coupled stellar evolution and atmospheric modeling of stars with initial masses between 20 Msun and 120 Msun. We found that the 20 Msun and 25 Msun rotating models, before exploding as SN, have spectra that do not resem...

  2. The Masses of Supernova Remnant Progenitors

    Science.gov (United States)

    Williams, Benjamin

    2012-10-01

    One of the key constraints on the production of supernovae {SNe} is the initial mass of the stars that eventually end in these cataclysmic events. Historically it has been very difficult to obtain estimates of the masses of SN progenitors because there have only been a few dozen nearby events, only a handful of which have high-quality precursor imaging.We propose dramatically increasing the number of SNe with progenitor mass estimates by applying an exciting new technique to HST archival data in M31 and M33. Through detailed modeling of the stellar populations surrounding the location of any known SNe, we can constrain the progenitor mass. Since supernova remnants {SNRs} mark the locations of SNe for the past 20,000 years and M31 and M33 contain hundreds of these objects, detailed studies of the stellar populations at these locations will constrain the progenitor masses of potentially hundreds of events. After correlating archival HST imaging with the SNR positions, there is useful data for 137 SNRs. We have already measured the progenitor masses for 65 SNRs in M31 and plan to apply our method to 72 SNRs in M33. This proposal will fund the publication of our M31 measurements, analysis of the M33 SNRs, and public release of our photometry. Ultimately, our work will increase the existing sample of SN progenitor masses in the literature by a factor of 20.

  3. Handbook of Supernovae

    Science.gov (United States)

    Athem Alsabti, Abdul

    2015-08-01

    Since the discovery of pulsars in 1967, few celestial phenomena have fascinated amateur and professional astronomers, and the public, more than supernovae - dying stars that explode spectacularly and, in so doing, may outshine a whole galaxy. Thousands of research papers, reviews, monographs and books have been published on this subject. These publications are often written either for a highly specific level of expertise or education, or with respect to a particular aspect of supernovae research. However, the study of supernovae is a very broad topic involving many integral yet connected aspects, including physics, mathematics, computation, history, theoretical studies and observation. More specifically, areas of study include historical supernovae, the different types and light curves, nucleosynthesis, explosion mechanisms, formation of black holes, neutron stars, cosmic rays, neutrinos and gravitational waves. Related questions include how supernovae remnants interact with interstellar matter nearby and how do these events affect the formation of new stars or planetary systems? Could they affect existing planetary systems? Closer to home, did any supernovae affect life on earth in the past or could they do so in the future? And on the larger scale, how did supernovae observations help measure the size and expansion of the universe? All these topics, and more, are to be covered in a new reference work, consisting of more than 100 articles and more than 1700 pages. It is intended to cover all the main facets of current supernovae research. It will be pitched at or above the level of a new postgraduate student, who will have successfully studied physics (or a similar scientific subject) to Bachelor degree level. It will be available in both print and electronic (updatable) formats, with the exception of the first section, which will consist of a review of all the topics of the handbook at a level that allows anyone with basic scientific knowledge to grasp the

  4. Supernova bounds on the dark photon using its electromagnetic decay

    Directory of Open Access Journals (Sweden)

    Demos Kazanas

    2015-01-01

    Full Text Available The hypothetical massive dark photon (γ′ which has kinetic mixing with the SM photon can decay electromagnetically to e+e− pairs if its mass m exceeds 2me, and otherwise into three SM photons. These decays yield cosmological and supernovae associated signatures. We briefly discuss these signatures, particularly in connection with the supernova SN1987A, and delineate the extra constraints that arise on the mass and mixing parameter of the dark photon. In particular, we find that for dark photon mass mγ′ in the 5–20 MeV range arguments based on supernova 1987A observations lead to a bound on ϵ which is about 300 times stronger than the presently existing bounds based on energy loss arguments.

  5. 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).

  6. Supernova 1987A at 30 years

    Science.gov (United States)

    Fransson, Claes

    2016-10-01

    This programme will provide a 30 year legacy point for SN 1987A, the brightest supernova since 1604. HST is the essential tool for resolving and analysing SN 1987A's several physical components. The inner, asymmetric ejecta are being heated by X-rays from the circumstellar ring and allow us to directly observe the geometry of the explosion. At the same time the fastest-moving ejecta are interacting with the ring, giving rise to bright emission from shocks. Our latest observations show that the ring is fading and that new spots are appearing outside, signalling that the blast wave has passed the ring and is now interacting with previously unseen material. It is also the beginning of the end for the ring. Here we propose to use COS and STIS to obtain a complete UV/optical spectrum of the ejecta and ring. The spectrum will enable a detailed modelling of the nucleosynthesis, which is a powerful diagnostic of the explosion, and provide a unique opportunity to study a supernova spectrum in the transition phase between a radioactively powered supernova and a shock heated remnant. It will also allow us to distinguish between different excitation mechanisms for the molecular hydrogen, recently discovered in the NIR. We also propose a set of broad and narrow band images to monitor the evolution of the flux and morphology of ejecta, ring and new spots outside the ring. The latter will tell us about the mass-loss history of the progenitor. The proposed observations will provide a crucial complement to recent Herschel and ALMA observations of dust, CO and SiO in the ejecta.

  7. Classification of Gaia17cyr as a Ia supernova

    Science.gov (United States)

    Dennefeld, M.

    2017-11-01

    M. Dennefeld (IAP-Paris and UPMC) reports observations of Gaia supernovae candidates with the SAAO 74" telescope equiped with the SpUpNIC spectrograph. Observations during the night of Nov. 23 covered the range 3600-9200 A and the spectral resolution was 5.8 A. Classifications were made with the help of GELATO (Harutyunyan et al. 2008, A & A, 488, 383) Gaia17cyr (=AT2017igq) is classified as a SN Ia, a few days past maximum.

  8. The interest in neutrinos from core collapse supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Costantini, M.L. [Universita dell' Aquila, I-67010 (Italy); Ianni, A. [Universita dell' Aquila, I-67010 (Italy); Vissani, F. [INFN, Laboratori Nazionali del Gran Sasso, I-67010 Assergi (AQ) (Italy)

    2005-02-15

    The understanding of core collapse supernovae (SN) is an important open problem. These objects are intense sources of neutrinos, that can be observed with several types of terrestrial detectors. These two simple considerations, already, motivate close attention toward neutrino interactions in the region from few to 200 MeV. In this work, we offer a selection of results and expectations, and discuss important goals still to be reached.

  9. Variation of cosmic ray injection across supernova shocks

    OpenAIRE

    Voelk, H. J.; Berezhko, E. G.; Ksenofontov, L. T.

    2003-01-01

    The injection rate of suprathermal protons into the diffusive shock acceleration process should vary strongly over the surface of supernova remnant shocks. These variations and the absolute value of the injection rate are investigated. In the simplest case, like for SN 1006, the shock can be approximated as being spherical in a uniform large-scale magnetic field. The injection rate depends strongly on the shock obliquity and diminishes as the angle between the ambient field and the shock norm...

  10. The Influence of Host Galaxies in Type Ia Supernova Cosmology

    Science.gov (United States)

    Uddin, Syed A.; Mould, Jeremy; Lidman, Chris; Ruhlmann-Kleider, Vanina; Zhang, Bonnie R.

    2017-10-01

    We use a sample of 1338 spectroscopically confirmed and photometrically classified Type Ia supernovae (SNe Ia) sourced from Carnegie Supernova Project, Center for Astrophysics Supernova Survey, Sloan Digital Sky Survey-II, and SuperNova Legacy Survey SN samples to examine the relationships between SNe Ia and the galaxies that host them. Our results provide confirmation with improved statistical significance that SNe Ia, after standardization, are on average more luminous in massive hosts (significance >5σ), and decline more rapidly in massive hosts (significance >9σ) and in hosts with low specific star formation rates (significance >8σ). We study the variation of these relationships with redshift and detect no evolution. We split SNe Ia into pairs of subsets that are based on the properties of the hosts and fit cosmological models to each subset. Including both systematic and statistical uncertainties, we do not find any significant shift in the best-fit cosmological parameters between the subsets. Among different SN Ia subsets, we find that SNe Ia in hosts with high specific star formation rates have the least intrinsic scatter (σ int = 0.08 ± 0.01) in luminosity after standardization.

  11. Gamma-ray line measurements from supernova explosions

    Science.gov (United States)

    Diehl, Roland

    2017-02-01

    Gamma ray lines are expected to be emitted as part of the afterglow of supernova explosions, because radioactive decay of freshly synthesised nuclei occurs. Significant radioactive gamma ray line emission is expected from 56Ni and 44Ti decay on time scales of the initial explosion (56Ni, τ ~days) and the young supernova remnant (44Ti,τ ~90 years). Less specific, and rather informative for the supernova population as a whole, are lessons from longer lived isotopes such as 26Al and 60Fe. From isotopes of elements heavier than iron group elements, any interesting gamma-ray line emission is too faint to be observable. Measurements with space-based gamma-ray telescopes have obtained interesting gamma ray line emissions from two core collapse events, Cas A and SN1987A, and one thermonuclear event, SN2014J. We discuss INTEGRAL data from all above isotopes, including all line and continuum signatures from these two objects, and the surveys for more supernovae, that have been performed by gamma ray spectrometry. Our objective here is to illustrate what can be learned from gamma-ray line emission properties about the explosions and their astrophysics.

  12. Probing Late-Stage Stellar Evolution through Robotic Follow-Up of Nearby Supernovae

    Science.gov (United States)

    Hosseinzadeh, Griffin

    2018-01-01

    Many of the remaining uncertainties in stellar evolution can be addressed through immediate and long-term photometry and spectroscopy of supernovae. The early light curves of thermonuclear supernovae can contain information about the nature of the binary companion to the exploding white dwarf. Spectra of core-collapse supernovae can reveal material lost by massive stars in their final months to years. Thanks to a revolution in technology—robotic telescopes, high-speed internet, machine learning—we can now routinely discover supernovae within days of explosion and obtain well-sampled follow-up data for months and years. Here I present three major results from the Global Supernova Project at Las Cumbres Observatory that take advantage of these technological advances. (1) SN 2017cbv is a Type Ia supernova discovered within a day of explosion. Early photometry shows a bump in the U-band relative to previously observed Type Ia light curves, possibly indicating the presence of a nondegenerate binary companion. (2) SN 2016bkv is a low-luminosity Type IIP supernova also caught very young. Narrow emission lines in the earliest spectra indicate interaction between the ejecta and a dense shell of circumstellar material, previously observed only in the brightest Type IIP supernovae. (3) Type Ibn supernovae are a rare class that interact with hydrogen-free circumstellar material. An analysis of the largest-yet sample of this class has found that their light curves are much more homogeneous and faster-evolving than their hydrogen-rich counterparts, Type IIn supernovae, but that their maximum-light spectra are more diverse.

  13. Observational studies of core-collapse supernova progenitors and their environments

    Science.gov (United States)

    Kangas, Tuomas

    2017-04-01

    In this doctoral thesis, core-collapse supernova progenitor stars are studied. Different ways to gain information on the progenitor stars of core-collapse supernovae are explored, with an emphasis on using the environments of supernovae. In the articles included in the thesis, various such methods are demonstrated and utilized to constrain the progenitor stars of different types of supernovae. The results have implications for the theory of stellar evolution, especially the relatively poorly understood evolution of stars massive enough to explode as core-collapse supernovae and, in particular, the role of mass loss in such stars. In Paper I, the associations between different types of core-collapse supernovae and the emission of their strongly star-forming host galaxies at different wavelengths are studied statistically. The radial distributions of these supernova types are also examined and compared to those in normal galaxies. In Paper II, the associations between different types of massive stars and star-forming regions in nearby galaxies are compared to studies using supernovae in an effort to approach the method quantitatively. The connection between type II-P supernovae and red supergiants, as well as results from massive main-sequence stars, are used to verify the validity of the method, and systematic effects are investigated. In Paper III, the results of a detailed follow-up programme of the interacting type II-L supernova SN 2013fc are presented. The supernova is found to be similar to the well-studied event SN 1998S. The environment of the event is compared to stellar population models, and the progenitor of SN 2013fc is found to be consistent with a massive red supergiant star. Paper IV describes the follow-up of the type Ic superluminous supernova Gaia16apd. Magnetar fits to the light curve are performed. The event is consistent with being powered by the spin-down of a newborn magnetar, and its spectroscopic and photometric evolution intermediate

  14. Preparatory studies for the WFIRST supernova cosmology measurements

    Science.gov (United States)

    Perlmutter, Saul

    tune details, like the wavelength coverage and S/N requirements, of the WFIRST IFS to capitalize on these systematic error reduction methods. b) Supernova extraction and host galaxy subtractions. The underlying light of the host galaxy must be subtracted from the supernova images making up the lightcurves. Using the IFS to provide the lightcurve points via spectrophotometry requires the subtraction of a reference spectrum of the galaxy taken after the supernova light has faded to a negligible level. We plan to apply the expertise obtained from the SNfactory to develop galaxy background procedures that minimize the systematic errors introduced by this step in the analysis. c) Instrument calibration and ground to space cross calibration. Calibrating the entire supernova sample will be a challenge as no standard stars exist that span the range of magnitudes and wavelengths relevant to the WFIRST survey. Linking the supernova measurements to the relatively brighter standards will require several links. WFIRST will produce the high redshift sample, but the nearby supernova to anchor the Hubble diagram will have to come from ground based observations. Developing algorithms to carry out the cross calibration of these two samples to the required one percent level will be an important goal of our proposal. An integral part of this calibration will be to remove all instrumental signatures and to develop unbiased measurement techniques starting at the pixel level. We then plan to pull the above studies together in a synthesis to produce a correlated error matrix. We plan to develop a Fisher Matrix based model to evaluate the correlated error matrix due to the various systematic errors discussed above. A realistic error model will allow us to carry out a more reliable estimates of the eventual errors on the measurement of the cosmological parameters, as well as serve as a means of optimizing and fine tuning the requirements for the instruments and survey strategies.

  15. The Remnant of Supernova 1987A

    Science.gov (United States)

    McCray, Richard; Fransson, Claes

    2016-09-01

    Although it has faded by a factor of ˜107, SN 1987A is still bright enough to be observed in almost every band of the electromagnetic spectrum. Today, the bolometric luminosity of the debris is dominated by a far-infrared (˜200μm) continuum from ˜0.5 M⊙ of dust grains in the interior debris. The dust is heated by UV, optical, and near-infrared (NIR) emission resulting from radioactive energy deposition by 44Ti. The optical light of the supernova debris is now dominated by illumination of the debris by X-rays resulting from the impact of the outer supernova envelope with an equatorial ring (ER) of gas that was expelled some 20,000 years before the supernova explosion. X-ray and optical observations trace a complex system of shocks resulting from this impact, whereas radio observations trace synchrotron radiation from relativistic electrons accelerated by these shocks. The luminosity of the remnant is dominated by an NIR (˜20μm) continuum from dust grains in the ER heated by collisions with ions in the X-ray emitting gas. With the Atacama Large Millimeter Array (ALMA), we can observe the interior debris at millimeter/submillimeter wavelengths, which are not absorbed by the interior dust. The ALMA observations reveal bright emission lines from rotational transitions of CO and SiO lines that provide a new window into the interior structure of the supernova debris. Optical, NIR, and ALMA observations all indicate strongly asymmetric ejecta. Intensive searches have failed to yield any evidence for the compact object expected to reside at the center of the remnant. The current upper limit to the luminosity of such an object is a few tens of solar luminosities.

  16. Broad-lined Supernova 2016coi with a Helium Envelope

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, Masayuki [Department of Physics, Faculty of Science and Engineering, Konan University, Okamoto, Kobe, Hyogo 658-8501 (Japan); Nakaoka, Tatsuya; Kawabata, Miho [Department of Physical Science, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan); Tanaka, Masaomi [National Astronomical Observatory of Japan, National Institutes of Natural Sciences, Osawa, Mitaka, Tokyo 181-8588 (Japan); Maeda, Keiichi [Department of Astronomy, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); Honda, Satoshi; Hosoya, Kensuke; Karita, Mayu; Morihana, Kumiko [Nishi-Harima Astronomical Observatory, Center for Astronomy, University of Hyogo, 407-2 Nishigaichi, Sayo-cho, Sayo, Hyogo 679-5313 (Japan); Hanayama, Hidekazu [Ishigakijima Astronomical Observatory, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 1024-1 Arakawa, Ishigaki, Okinawa 907-0024 (Japan); Morokuma, Tomoki [Institute of Astronomy, Graduate School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Imai, Masataka [Department of Cosmosciences, Graduate School of Science, Hokkaido University, Kita 10 Nishi8, Kita-ku, Sapporo 060-0810 (Japan); Kinugasa, Kenzo [Nobeyama Radio Observatory, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 462-2 Nobeyama, Minamimaki, Minamisaku, Nagano 384-1305 (Japan); Murata, Katsuhiro L. [Department of Astrophysics, Nagoya University, Chikusa-ku, Nagoya 464-8602 (Japan); Nishimori, Takefumi; Gima, Hirotaka; Ito, Ayano; Morikawa, Yuto; Murakami, Kotone [Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065 (Japan); Hashimoto, Osamu, E-mail: yamanaka@center.konan-u.ac.jp [Gunma Astronomical Observatory, Takayama, Gunma 377-0702 (Japan); and others

    2017-03-01

    We present the early-phase spectra and the light curves of the broad-lined (BL) supernova (SN) 2016coi from t = 7 to 67 days after the estimated explosion date. This SN was initially reported as a BL Type SN Ic (SN Ic-BL). However, we found that spectra up to t = 12 days exhibited the He i λ 5876, λ 6678, and λ 7065 absorption lines. We show that the smoothed and blueshifted spectra of normal SNe Ib are remarkably similar to the observed spectrum of SN 2016coi. The line velocities of SN 2016coi were similar to those of SNe Ic-BL and significantly faster than those of SNe Ib. Analyses of the line velocity and light curve suggest that the kinetic energy and the total ejecta mass of SN 2016coi are similar to those of SNe Ic-BL. Together with BL SNe 2009bb and 2012ap, for which the detection of He i was also reported, these SNe could be transitional objects between SNe Ic-BL and SNe Ib, and be classified as BL Type “Ib” SNe (SNe “Ib”-BL). Our work demonstrates the diversity of the outermost layer in BL SNe, which should be related to the variety of the evolutionary paths.

  17. Detecting supernova neutrinos with iron and lead detectors

    Science.gov (United States)

    Bandyopadhyay, Abhijit; Bhattacharjee, Pijushpani; Chakraborty, Sovan; Kar, Kamales; Saha, Satyajit

    2017-03-01

    Supernova (SN) neutrinos can excite the nuclei of various detector materials beyond their neutron emission thresholds through charged current (CC) and neutral current (NC) interactions. The emitted neutrons, if detected, can be a signal for the supernova event. Here we present the results of our study of SN neutrino detection through the neutron channel in 208Pb and 56Fe detectors for realistic neutrino fluxes and energies given by the recent Basel/Darmstadt simulations for an 18 solar mass progenitor SN at a distance of 10 kpc. We find that, in general, the number of neutrons emitted per kiloton (kTon) of detector material for the neutrino luminosities and average energies of the different neutrino species as given by the Basel/Darmstadt simulations are significantly lower than those estimated in previous studies based on the results of earlier SN simulations. At the same time, we highlight the fact that, although the total number of neutrons produced per kTon in a 56Fe detector is more than an order of magnitude lower than that for 208Pb, the dominance of the flavor blind NC events in the case of 56Fe, as opposed to the dominance of νe induced CC events in the case of 208Pb, offers a complementarity between the two detector materials so that simultaneous detection of SN neutrinos in a 208Pb and a sufficiently large 56Fe 56 detector suitably instrumented for neutron detection may allow estimating the fraction of the total μ and τ flavored neutrinos in the SN neutrino flux and thereby probing the emission mechanism as well as flavor oscillation scenarios of the SN neutrinos.

  18. Modeling Core Collapse Supernovae

    Science.gov (United States)

    Mezzacappa, Anthony

    2017-01-01

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

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

    CERN Document Server

    2003-01-01

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

  20. The Foundation Supernova Survey: motivation, design, implementation, and first data release

    Science.gov (United States)

    Foley, Ryan J.; Scolnic, Daniel; Rest, Armin; Jha, S. W.; Pan, Y.-C.; Riess, A. G.; Challis, P.; Chambers, K. C.; Coulter, D. A.; Dettman, K. G.; Foley, M. M.; Fox, O. D.; Huber, M. E.; Jones, D. O.; Kilpatrick, C. D.; Kirshner, R. P.; Schultz, A. S. B.; Siebert, M. R.; Flewelling, H. A.; Gibson, B.; Magnier, E. A.; Miller, J. A.; Primak, N.; Smartt, S. J.; Smith, K. W.; Wainscoat, R. J.; Waters, C.; Willman, M.

    2018-03-01

    The Foundation Supernova Survey aims to provide a large, high-fidelity, homogeneous, and precisely calibrated low-redshift Type Ia supernova (SN Ia) sample for cosmology. The calibration of the current low-redshift SN sample is the largest component of systematic uncertainties for SN cosmology, and new data are necessary to make progress. We present the motivation, survey design, observation strategy, implementation, and first results for the Foundation Supernova Survey. We are using the Pan-STARRS telescope to obtain photometry for up to 800 SNe Ia at z ≲ 0.1. This strategy has several unique advantages: (1) the Pan-STARRS system is a superbly calibrated telescopic system, (2) Pan-STARRS has observed 3/4 of the sky in grizyP1 making future template observations unnecessary, (3) we have a well-tested data-reduction pipeline, and (4) we have observed ˜3000 high-redshift SNe Ia on this system. Here, we present our initial sample of 225 SN Ia grizP1 light curves, of which 180 pass all criteria for inclusion in a cosmological sample. The Foundation Supernova Survey already contains more cosmologically useful SNe Ia than all other published low-redshift SN Ia samples combined. We expect that the systematic uncertainties for the Foundation Supernova Sample will be two to three times smaller than other low-redshift samples. We find that our cosmologically useful sample has an intrinsic scatter of 0.111 mag, smaller than other low-redshift samples. We perform detailed simulations showing that simply replacing the current low-redshift SN Ia sample with an equally sized Foundation sample will improve the precision on the dark energy equation-of-state parameter by 35 per cent, and the dark energy figure of merit by 72 per cent.

  1. A faint type of supernova from a white dwarf with a helium-rich companion.

    Science.gov (United States)

    Perets, H B; Gal-Yam, A; Mazzali, P A; Arnett, D; Kagan, D; Filippenko, A V; Li, W; Arcavi, I; Cenko, S B; Fox, D B; Leonard, D C; Moon, D-S; Sand, D J; Soderberg, A M; Anderson, J P; James, P A; Foley, R J; Ganeshalingam, M; Ofek, E O; Bildsten, L; Nelemans, G; Shen, K J; Weinberg, N N; Metzger, B D; Piro, A L; Quataert, E; Kiewe, M; Poznanski, D

    2010-05-20

    Supernovae are thought to arise from two different physical processes. The cores of massive, short-lived stars undergo gravitational core collapse and typically eject a few solar masses during their explosion. These are thought to appear as type Ib/c and type II supernovae, and are associated with young stellar populations. In contrast, the thermonuclear detonation of a carbon-oxygen white dwarf, whose mass approaches the Chandrasekhar limit, is thought to produce type Ia supernovae. Such supernovae are observed in both young and old stellar environments. Here we report a faint type Ib supernova, SN 2005E, in the halo of the nearby isolated galaxy, NGC 1032. The 'old' environment near the supernova location, and the very low derived ejected mass ( approximately 0.3 solar masses), argue strongly against a core-collapse origin. Spectroscopic observations and analysis reveal high ejecta velocities, dominated by helium-burning products, probably excluding this as a subluminous or a regular type Ia supernova. We conclude that it arises from a low-mass, old progenitor, likely to have been a helium-accreting white dwarf in a binary. The ejecta contain more calcium than observed in other types of supernovae and probably large amounts of radioactive (44)Ti.

  2. SN Refsdal

    DEFF Research Database (Denmark)

    Kelly, P. L.; Brammer, G.; Selsing, J.

    2016-01-01

    (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...... 1987A, we estimate it would have an ejecta mass of 20+-5 solar masses. The evolution of the light curve at late times will provide additional evidence about the potential existence of any substantial circumstellar material (CSM). Using MOSFIRE and X-shooter spectra, we estimate a subsolar host-galaxy...

  3. RAPIDLY RISING TRANSIENTS IN THE SUPERNOVA—SUPERLUMINOUS SUPERNOVA GAP

    Energy Technology Data Exchange (ETDEWEB)

    Arcavi, Iair; Howell, D. Andrew [Las Cumbres Observatory Global Telescope, 6740 Cortona Dr., Suite 102, Goleta, CA 93111 (United States); Wolf, William M. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Bildsten, Lars; McCully, Curtis; Valenti, Stefano [Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106 (United States); Leloudas, Giorgos; Gal-Yam, Avishay; Katz, Boaz [Department of Particle Physics and Astrophysics, The Weizmann Institute of Science, Rehovot, 76100 (Israel); Hardin, Delphine; Astier, Pierre; Balland, Cristophe [LPNHE, CNRS-IN2P3 and University of Paris VI and VII, F-75005 Paris (France); Prajs, Szymon; Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Perley, Daniel A. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Svirski, Gilad [Racah Institute for Physics, The Hebrew University, Jerusalem 91904 (Israel); Cenko, S. Bradley [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Lidman, Chris [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia); Carlberg, Ray G. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H8 (Canada); Conley, Alex, E-mail: iarcavi@lcogt.net [Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309-389 (United States); and others

    2016-03-01

    We present observations of four rapidly rising (t{sub rise} ≈ 10 days) transients with peak luminosities between those of supernovae (SNe) and superluminous SNe (M{sub peak} ≈ −20)—one discovered and followed by the Palomar Transient Factory (PTF) and three by the Supernova Legacy Survey. The light curves resemble those of SN 2011kl, recently shown to be associated with an ultra-long-duration gamma-ray burst (GRB), though no GRB was seen to accompany our SNe. The rapid rise to a luminous peak places these events in a unique part of SN phase space, challenging standard SN emission mechanisms. Spectra of the PTF event formally classify it as an SN II due to broad Hα emission, but an unusual absorption feature, which can be interpreted as either high velocity Hα (though deeper than in previously known cases) or Si ii (as seen in SNe Ia), is also observed. We find that existing models of white dwarf detonations, CSM interaction, shock breakout in a wind (or steeper CSM), and magnetar spin down cannot readily explain the observations. We consider the possibility that a “Type 1.5 SN” scenario could be the origin of our events. More detailed models for these kinds of transients and more constraining observations of future such events should help to better determine their nature.

  4. Exploring Cosmology with Supernovae

    DEFF Research Database (Denmark)

    Li, Xue

    distribution of strong gravitational lensing is developed. For Type Ia supernova (SNe Ia), the rate is lower than core-collapse supernovae (CC SNe). The rate of SNe Ia declines beyond z 1:5. Based on these reasons, we investigate a potential candidate to measure cosmological distance: GRB......-SNe. They are a subclass of CC SNe. Light curves of GRB-SNe are obtained and their properties are studied. We ascertain that the properties of GRB-SNe make them another candidate for standardizable candles in measuring the cosmic distance. Cosmological parameters M and are constrained with the help of GRB-SNe. The first...

  5. Neutrinos in supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Cooperstein, J.

    1986-10-01

    The role of neutrinos in Type II supernovae is discussed. An overall view of the neutrino luminosity as expected theoretically is presented. The different weak interactions involved are assessed from the standpoint of how they exchange energy, momentum, and lepton number. Particular attention is paid to entropy generation and the path to thermal and chemical equilibration, and to the phenomenon of trapping. Various methods used to calculate the neutrino flows are considered. These include trapping and leakage schemes, distribution-averaged transfer, and multi-energy group methods. The information obtained from the neutrinos caught from Supernova 1987a is briefly evaluated. 55 refs., 7 figs.

  6. The massive binary companion star to the progenitor of supernova 1993J.

    Science.gov (United States)

    Maund, Justyn R; Smartt, Stephen J; Kudritzki, Rolf P; Podsiadlowski, Philipp; Gilmore, Gerard F

    2004-01-08

    The massive star that underwent a collapse of its core to produce supernova (SN)1993J was subsequently identified as a non-variable red supergiant star in images of the galaxy M81 taken before explosion. It showed an excess in ultraviolet and B-band colours, suggesting either the presence of a hot, massive companion star or that it was embedded in an unresolved young stellar association. The spectra of SN1993J underwent a remarkable transformation from the signature of a hydrogen-rich type II supernova to one of a helium-rich (hydrogen-deficient) type Ib. The spectral and photometric peculiarities were best explained by models in which the 13-20 solar mass supergiant had lost almost its entire hydrogen envelope to a close binary companion, producing a 'type IIb' supernova, but the hypothetical massive companion stars for this class of supernovae have so far eluded discovery. Here we report photometric and spectroscopic observations of SN1993J ten years after the explosion. At the position of the fading supernova we detect the unambiguous signature of a massive star: the binary companion to the progenitor.

  7. SPECTRAL IDENTIFICATION OF AN ANCIENT SUPERNOVA USING LIGHT ECHOES IN THE LMC

    Energy Technology Data Exchange (ETDEWEB)

    Rest, A; Matheson, T; Blondin, S; Bergmann, M; Welch, D L; Suntzeff, N B; Smith, R C; Olsen, K; Prieto, J L; Garg, A; Challis, P; Stubbs, C; Hicken, M; Modjaz, M; Wood-Vasey, W M; Zenteno, A; Damke, G; Newman, A; Huber, M; Cook, K H; Nikolaev, S; Becker, A C; Miceli, A; Covarrubias, R; Morelli, L; Pignata, G; Clocchiatti, A; Minniti, D; Foley, R J

    2008-02-07

    We report the successful identification of the type of the supernova responsible for the supernova remnant SNR 0509-675 in the Large Magellanic Cloud (LMC) using Gemini spectra of surrounding light echoes. The ability to classify outbursts associated with centuries-old remnants provides a new window into several aspects of supernova research and is likely to be successful in providing new constraints on additional LMC supernovae as well as their historical counterparts in the Milky Way Galaxy (MWG). The combined spectrum of echo light from SNR 0509-675 shows broad emission and absorption lines consistent with a supernova (SN) spectrum. We create a spectral library consisting of 26 SNe Ia and 6 SN Ib/c that are time-integrated, dust-scattered by LMC dust, and reddened by the LMC and MWG. We fit these SN templates to the observed light echo spectrum using {chi}{sup 2} minimization as well as correlation techniques, and we find that overluminous 91T-like SNe Ia with {Delta}m{sub 15} < 0.9 match the observed spectrum best.

  8. Measurements of the Rate of Type Ia Supernovae at Redshift z < ~0.3 from the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Dilday, Benjamin; /Rutgers U., Piscataway /Chicago U. /KICP, Chicago; Smith, Mathew; /Cape Town U., Dept. Math. /Portsmouth U.; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Becker, Andrew; /Washington U., Seattle, Astron. Dept.; Bender, Ralf; /Munich, Tech. U. /Munich U. Observ.; Castander, Francisco; /Barcelona, IEEC; Cinabro, David; /Wayne State U.; Filippenko, Alexei V.; /UC, Berkeley; Frieman, Joshua A.; /Chicago U. /Fermilab; Galbany, Lluis; /Barcelona, IFAE; Garnavich, Peter M.; /Notre Dame U. /Stockholm U., OKC /Stockholm U.

    2010-01-01

    We present a measurement of the volumetric Type Ia supernova (SN Ia) rate based on data from the Sloan Digital Sky Survey II (SDSS-II) Supernova Survey. The adopted sample of supernovae (SNe) includes 516 SNe Ia at redshift z {approx}< 0.3, of which 270 (52%) are spectroscopically identified as SNe Ia. The remaining 246 SNe Ia were identified through their light curves; 113 of these objects have spectroscopic redshifts from spectra of their host galaxy, and 133 have photometric redshifts estimated from the SN light curves. Based on consideration of 87 spectroscopically confirmed non-Ia SNe discovered by the SDSS-II SN Survey, we estimate that 2.04{sub -0.95}{sup +1.61}% of the photometric SNe Ia may be misidentified. The sample of SNe Ia used in this measurement represents an order of magnitude increase in the statistics for SN Ia rate measurements in the redshift range covered by the SDSS-II Supernova Survey. If we assume a SN Ia rate that is constant at low redshift (z < 0.15), then the SN observations can be used to infer a value of the SN rate of r{sub V} = (2.69{sub -0.30-0.01}{sup +0.34+0.21}) x 10{sup -5} SNe yr{sup -1} Mpc{sup -3} (H{sub 0}/(70 km s{sup -1} Mpc{sup -1})){sup 3} at a mean redshift of {approx} 0.12, based on 79 SNe Ia of which 72 are spectroscopically confirmed. However, the large sample of SNe Ia included in this study allows us to place constraints on the redshift dependence of the SN Ia rate based on the SDSS-II Supernova Survey data alone. Fitting a power-law model of the SN rate evolution, r{sub V} (z) = A{sub p} x ((1+z)/(1+z{sub 0})){sup {nu}}, over the redshift range 0.0 < z < 0.3 with z{sub 0} = 0.21, results in A{sub p} = (3.43{sub -0.15}{sup +0.15}) x 10{sup -5} SNe yr{sup -1} Mpc{sup -3} (H{sub 0}/(70 km s{sup -1} Mpc{sup -1})){sup 3} and {nu} = 2.04{sub -0.89}{sup +0.90}.

  9. Radioactive Iron Rain: Transporting 60Fe in Supernova Dust to the Ocean Floor

    Science.gov (United States)

    Fry, Brian J.; Fields, Brian D.; Ellis, John R.

    2016-08-01

    Several searches have found evidence of {}60{{Fe}} deposition, presumably from a near-Earth supernova (SN), with concentrations that vary in different locations on Earth. This paper examines various influences on the path of interstellar dust carrying {}60{{Fe}} from an SN through the heliosphere, with the aim of estimating the final global distribution on the ocean floor. We study the influences of magnetic fields, angle of arrival, wind, and ocean cycling of SN material on the concentrations at different locations. We find that the passage of SN material through the mesosphere/lower thermosphere has the greatest influence on the final global distribution, with ocean cycling causing lesser alteration as the SN material sinks to the ocean floor. SN distance estimates in previous works that assumed a uniform distribution are a good approximation. Including the effects on surface distributions, we estimate a distance of {46}-6+10 pc for an 8{--}10 {M}⊙ SN progenitor. This is consistent with an SN occurring within the Tuc-Hor stellar group ˜2.8 Myr ago, with SN material arriving on Earth ˜2.2 Myr ago. We note that the SN dust retains directional information to within 1◦ through its arrival in the inner solar system, so that SN debris deposition on inert bodies such as the Moon will be anisotropic, and thus could in principle be used to infer directional information. In particular, we predict that existing lunar samples should show measurable {}60{{Fe}} differences.

  10. Baby supernovae through the looking glass at long wavelengths.

    Science.gov (United States)

    Chandra, Poonam; Ray, Alak

    2004-09-01

    We emphasize the importance of observations of young supernovae in wide radio band. We argue on the basis of observational results that only high- or only low-frequency data is not sufficient to get full physical picture of the shocked plasma. In SN 1993J, the composite spectrum obtained with Very Large Array (VLA) and Giant Metrewave Radio Telescope (GMRT), around day 3200, shows observational evidence of synchrotron cooling, which leads us to the direct determination of the magnetic field independent of the equipartition assumption, as well as the relative strengths of the magnetic field and relativistic particle energy densities. The GMRT low-frequency light curves of SN 1993J suggest the modification in the radio emission models developed on the basis of VLA data alone. The composite radio spectrum of SN 2003bg on day 350 obtained with GMRT plus VLA strongly supports internal synchrotron self absorption as the dominant absorption mechanism.

  11. Cooling of young neutron stars in GRB associated to supernovae

    Science.gov (United States)

    Negreiros, R.; Ruffini, R.; Bianco, C. L.; Rueda, J. A.

    2012-04-01

    Context. The traditional study of neutron star cooling has been generally applied to quite old objects such as the Crab Pulsar (957 years) or the central compact object in Cassiopeia A (330 years) with an observed surface temperature ~106 K. However, recent observations of the late (t = 108-109 s) emission of the supernovae (SNe) associated to GRBs (GRB-SN) show a distinctive emission in the X-ray regime consistent with temperatures ~107-108 K. Similar features have been also observed in two Type Ic SNe SN 2002ap and SN 1994I that are not associated to GRBs. Aims: We advance the possibility that the late X-ray emission observed in GRB-SN and in isolated SN is associated to a hot neutron star just formed in the SN event, here defined as a neo-neutron star. Methods: We discuss the thermal evolution of neo-neutron stars in the age regime that spans from ~1 min (just after the proto-neutron star phase) all the way up to ages atmosphere for young neutron stars. In this way we match the neo-neutron star luminosity to the observed late X-ray emission of the GRB-SN events: URCA-1 in GRB980425-SN1998bw, URCA-2 in GRB030329-SN2003dh, and URCA-3 in GRB031203-SN2003lw. Results: We identify the major role played by the neutrino emissivity in the thermal evolution of neo-neutron stars. By calibrating our additional heating source at early times to ~1012-1015 erg/g/s, we find a striking agreement of the luminosity obtained from the cooling of a neo-neutron stars with the prolonged (t = 108-109 s) X-ray emission observed in GRB associated with SN. It is therefore appropriate a revision of the boundary conditions usually used in the thermal cooling theory of neutron stars, to match the proper conditions of the atmosphere at young ages. The traditional thermal processes taking place in the crust might be enhanced by the extreme high-temperature conditions of a neo-neutron star. Additional heating processes that are still not studied within this context, such as e+e- pair creation by

  12. Spectroscopic Confirmation of DES13S2cmm: The first DES Superluminous Supernova

    Science.gov (United States)

    Papadopoulos, A.; Sullivan, M.; D'Andrea, C.; Nichol, R.; Maguire, K.; Kessler, R.; Covarrubias, R. A.; Cane, R.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Maartens, R.; Smith, M.; Barbary, K.; Bernstein, J. P.; Biswas, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Bloom, J. S.; Goldstein, D.; Kim, A.; Nugent, P.; Perlmutter, S.; Thomas, R. C.; Foley, R. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.

    2013-11-01

    We report optical spectroscopy of a supernova (SN) candidate discovered by the Dark Energy Survey (ATel #4668). The spectrum (595-940 nm) of DES13S2cmm was obtained using the FOcal Reducer and low dispersion Spectrograph 2 (FORS2) on the Very Large Telescope (VLT) of the European Southern Observatory (ESO) under a Director's Discretionary Time proposal.

  13. Eleventh-Century Supernovae: Another Way To Read The Medieval Sources?

    Science.gov (United States)

    Ghignoli, A.; Martocchia, A.; Polcaro, V. F.

    The supernova explosions of 1006 AD and 1054 AD are, probably, the astronomical events most carefully studied through the analysis of historical sources. But contradictions are still present in several sources concerning SN 1054 and the historical records are not consistent with the astronomical data. This short analysis aims to highlight all these aspects.

  14. Bolometric Light Curves of Peculiar Type II-P Supernovae

    Science.gov (United States)

    Lusk, Jeremy A.; Baron, E.

    2017-04-01

    We examine the bolometric light curves of five Type II-P supernovae (SNe 1998A, 2000cb, 2006V, 2006au, and 2009E), which are thought to originate from blue supergiant progenitors like that of SN 1987A, using a new python package named SuperBoL. With this code, we calculate SNe light curves using three different common techniques common from the literature: the quasi-bolometric method, which integrates the observed photometry, the direct integration method, which additionally corrects for unobserved flux in the UV and IR, and the bolometric correction method, which uses correlations between observed colors and V-band bolometric corrections. We present here the light curves calculated by SuperBoL, along with previously published light curves, as well as peak luminosities and 56Ni yields. We find that the direct integration and bolometric correction light curves largely agree with previously published light curves, but with what we believe to be more robust error calculations, with 0.2≲ δ {L}{bol}/{L}{bol}≲ 0.5. Peak luminosities and 56Ni masses are similarly comparable to previous work. SN 2000cb remains an unusual member of this sub-group, owing to the faster rise and flatter plateau than the other supernovae in the sample. Initial comparisons with the NLTE atmosphere code PHOENIX show that the direct integration technique reproduces the luminosity of a model supernova spectrum to ˜5% when given synthetic photometry of the spectrum as input. Our code is publicly available. The ability to produce bolometric light curves from observed sets of broadband light curves should be helpful in the interpretation of other types of supernovae, particularly those that are not well characterized, such as extremely luminous supernovae and faint fast objects.

  15. Recording of Supernovae in Rock Art, A Case Study at the Paint Rock Pictograph Site

    Science.gov (United States)

    Houston, Gordon L.; Simonia, Irakli; NA

    2017-01-01

    The Paint Rock pictographs in central Texas and their use as solar markers were formally reported for the first time by Dr. R. Robert Robbins at the 1999 AAS meeting #193 in Austin, Texas. He reported the operations of the winter solstice marker and suggested the possibility of more, including a summer solstice solar marker. Since this first report, there have been many informal studies of the Paint Rock site. In 1955, William C. Miller made the first interpretation of rock art as depicting images of the Crab supernova of AD 1054, which has produced many reports at other rock art sites in the American Southwest, including one at Paint Rock. All of these claims have a star and crescent configuration. Recently, these claims have been dismissed. We propose that the second panel at Paint Rock is representative of Tycho Brahe's supernovae SN1572. Miller set up a set of restrictions and criteria to evaluate these potential claims. We discuss Miller's criteria and two additional sets of criteria to evaluate representations of historical records of supernovae sightings. Two sets of characteristics of supernovae are provided, the first being galactic location and the second observational characteristics of naked eye supernovae. Employing astronomical software, we show that the panel at Paint Rock meets the restrictions and criteria discussed, that leads to high confidence in stating it records Tycho Brahe's supernova SN1572.

  16. A TYPE Ia SUPERNOVA AT REDSHIFT 1.55 IN HUBBLE SPACE TELESCOPE INFRARED OBSERVATIONS FROM CANDELS

    Energy Technology Data Exchange (ETDEWEB)

    Rodney, Steven A.; Riess, Adam G.; Jones, David O. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Dahlen, Tomas; Ferguson, Henry C.; Casertano, Stefano; Grogin, Norman A. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Strolger, Louis-Gregory [Department of Physics, Western Kentucky University, Bowling Green, KY 42101 (United States); Hjorth, Jens; Frederiksen, Teddy F. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Weiner, Benjamin J. [Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States); Mobasher, Bahram [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Challis, Peter; Kirshner, Robert P. [Harvard/Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Faber, S. M. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 92064 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Garnavich, Peter; Hayden, Brian [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Graur, Or [Department of Astrophysics, Tel Aviv University, 69978 Tel Aviv (Israel); Jha, Saurabh W. [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); and others

    2012-02-10

    We report the discovery of a Type Ia supernova (SN Ia) at redshift z = 1.55 with the infrared detector of the Wide Field Camera 3 (WFC3-IR) on the Hubble Space Telescope (HST). This object was discovered in CANDELS imaging data of the Hubble Ultra Deep Field and followed as part of the CANDELS+CLASH Supernova project, comprising the SN search components from those two HST multi-cycle treasury programs. This is the highest redshift SN Ia with direct spectroscopic evidence for classification. It is also the first SN Ia at z > 1 found and followed in the infrared, providing a full light curve in rest-frame optical bands. The classification and redshift are securely defined from a combination of multi-band and multi-epoch photometry of the SN, ground-based spectroscopy of the host galaxy, and WFC3-IR grism spectroscopy of both the SN and host. This object is the first of a projected sample at z > 1.5 that will be discovered by the CANDELS and CLASH programs. The full CANDELS+CLASH SN Ia sample will enable unique tests for evolutionary effects that could arise due to differences in SN Ia progenitor systems as a function of redshift. This high-z sample will also allow measurement of the SN Ia rate out to z Almost-Equal-To 2, providing a complementary constraint on SN Ia progenitor models.

  17. LOSS Revisited. I. Unraveling Correlations between Supernova Rates and Galaxy Properties, as Measured in a Reanalysis of the Lick Observatory Supernova Search

    Energy Technology Data Exchange (ETDEWEB)

    Graur, Or [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Bianco, Federica B.; Huang, Shan; Modjaz, Maryam [CCPP, New York University, 4 Washington Place, New York, NY 10003 (United States); Shivvers, Isaac; Filippenko, Alexei V.; Li, Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Eldridge, J. J., E-mail: or.graur@cfa.harvard.edu [Department of Physics, University of Auckland, Private Bag 92019, Auckland (New Zealand)

    2017-03-10

    Most types of supernovae (SNe) have yet to be connected with their progenitor stellar systems. Here, we reanalyze the 10-year SN sample collected during 1998–2008 by the Lick Observatory Supernova Search (LOSS) in order to constrain the progenitors of SNe Ia and stripped-envelope SNe (SE SNe, i.e., SNe IIb, Ib, Ic, and broad-lined Ic). We matched the LOSS galaxy sample with spectroscopy from the Sloan Digital Sky Survey and measured SN rates as a function of galaxy stellar mass, specific star formation rate, and oxygen abundance (metallicity). We find significant correlations between the SN rates and all three galaxy properties. The SN Ia correlations are consistent with other measurements, as well as with our previous explanation of these measurements in the form of a combination of the SN Ia delay-time distribution and the correlation between galaxy mass and age. The ratio between the SE SN and SN II rates declines significantly in low-mass galaxies. This rules out single stars as SE SN progenitors, and is consistent with predictions from binary-system progenitor models. Using well-known galaxy scaling relations, any correlation between the rates and one of the galaxy properties examined here can be expressed as a correlation with the other two. These redundant correlations preclude us from establishing causality—that is, from ascertaining which of the galaxy properties (or their combination) is the physical driver for the difference between the SE SN and SN II rates. We outline several methods that have the potential to overcome this problem in future works.

  18. Extending Supernova Spectral Templates for Next Generation Space Telescope Observations

    Science.gov (United States)

    Roberts-Pierel, Justin; Rodney, Steven A.; Steven Rodney

    2018-01-01

    Widely used empirical supernova (SN) Spectral Energy Distributions (SEDs) have not historically extended meaningfully into the ultraviolet (UV), or the infrared (IR). However, both are critical for current and future aspects of SN research including UV spectra as probes of poorly understood SN Ia physical properties, and expanding our view of the universe with high-redshift James Webb Space Telescope (JWST) IR observations. We therefore present a comprehensive set of SN SED templates that have been extended into the UV and IR, as well as an open-source software package written in Python that enables a user to generate their own extrapolated SEDs. We have taken a sampling of core-collapse (CC) and Type Ia SNe to get a time-dependent distribution of UV and IR colors (U-B,r’-[JHK]), and then generated color curves are used to extrapolate SEDs into the UV and IR. The SED extrapolation process is now easily duplicated using a user’s own data and parameters via our open-source Python package: SNSEDextend. This work develops the tools necessary to explore the JWST’s ability to discriminate between CC and Type Ia SNe, as well as provides a repository of SN SEDs that will be invaluable to future JWST and WFIRST SN studies.

  19. Direct evidence for a supernova interacting with a large amount of hydrogen-free circumstellar material

    OpenAIRE

    Ben-Ami, S; Gal-Yam, A; Mazzali, PA; Gnat, O.; Modjaz, M.; Rabinak, I; Sullivan, M; Bildsten, L.; Poznanski, D.; Yaron, O.; Arcavi, I.; Bloom, JS; Horesh, A.; Kasliwal, MM; Kulkarni, SR

    2013-01-01

    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 ^(56)Ni/^(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 (~10^9 cm^(–3)). From the observed spect...

  20. Long gamma-ray bursts without visible supernovae: a case study of redshift estimators and alleged novel objects

    CERN Document Server

    Dado, S; De Rújula, Alvaro; Dado, Shlomo; Dar, Arnon

    2006-01-01

    There is an ongoing debate on whether or not the observational limits on a supernova (SN) associated with GRB060614 convincingly exclude a SN akin to SN1998bw as its originator, and provide evidence for a new class of long-duration GRBs. We discuss this issue in the contexts of indirect `redshift estimators' and of the fireball and cannonball models of GRBs. The latter explains the unusual properties of GRB060614: at its debated low redshift (0.125) they are predicted, as opposed to exceptional, if the associated SN is of `Pastorello's class'. Long-baseline radio data and deep optical data may test the proposed alternatives.

  1. Long Gamma-Ray Bursts without Visible Supernovae A Case Study of Redshift Estimators and Alleged Novel Objects

    CERN Document Server

    Dado, Shlomo; De Rújula, A; Plaga, Rainer

    2008-01-01

    It has been argued that the observational limits on a supernova (SN) associated with GRB 060614 convincingly exclude a SN akin to SN 1998bw as its originator and provide evidence for a new class of long-duration GRBs. We discuss this issue in the contexts of indirect "redshift estimators" and of the fireball and cannonball models of GRBs. The latter explains the unusual properties of GRB 060614: at its debated but favored low redshift (0.125), they are predicted, as opposed to exceptional, if the associated core-collapse SN is of a recently discovered, very faint type. We take the occasion to discuss the association between GRBs and SNe.

  2. On the nature of hydrogen-rich superluminous supernovae

    Science.gov (United States)

    Inserra, C.; Smartt, S. J.; Gall, E. E. E.; Leloudas, G.; Chen, T.-W.; Schulze, S.; Jerkstrand, A.; Nicholl, M.; Anderson, J. P.; Arcavi, I.; Benetti, S.; Cartier, R. A.; Childress, M.; Della Valle, M.; Flewelling, H.; Fraser, M.; Gal-Yam, A.; Gutiérrez, C. P.; Hosseinzadeh, G.; Howell, D. A.; Huber, M.; Kankare, E.; Krühler, T.; Magnier, E. A.; Maguire, K.; McCully, C.; Prajs, S.; Primak, N.; Scalzo, R.; Schmidt, B. P.; Smith, M.; Smith, K. W.; Tucker, B. E.; Valenti, S.; Wilman, M.; Young, D. R.; Yuan, F.

    2018-03-01

    We present two hydrogen-rich superluminous supernovae (SLSNe): SN2103hx and PS15br. These objects, together with SN2008es, are the only SLSNe showing a distinct, broad H α feature during the photospheric phase; also, they show no sign of strong interaction between fast moving ejecta and circumstellar shells in their early spectra. Despite the fact that the peak luminosity of PS15br is fainter than that of the other two objects, the spectrophotometric evolution is similar to SN2103hx and different from any other supernova in a similar luminosity space. We group all of them as SLSNe II and hence they are distinct from the known class of SLSN IIn. Both transients show a strong, multicomponent H α emission after 200 d past maximum, which we interpret as an indication of the interaction of the ejecta with an asymmetric, clumpy circumstellar material. The spectra and photometric evolution of the two objects are similar to Type II supernovae, although they have much higher luminosity and evolve on slower time-scales. This is qualitatively similar to how SLSNe I compare with normal type Ic, in that the former are brighter and evolve more slowly. We apply a magnetar and an interaction semi-analytical code to fit the light curves of our two objects and SN2008es. The overall observational data set would tend to favour the magnetar, or central engine, model as the source of the peak luminosity, although the clear signature of late-time interaction indicates that interaction can play a role in the luminosity evolution of SLSNe II at some phases.

  3. Catching Supernova Impostors

    Science.gov (United States)

    Elias-Rosa, Nancy

    2015-08-01

    Given the heterogeneity of the type IIn SNe (SN that show strong interaction with the circumstellar medium), sometimes sneak cases of powerful eruptions of luminous blue variables (LBV) copy the true appearance of a SN explosion. These cases are commonly known as ``SN impostors". Although the mechanisms triggering these eruptions are still unknown, recently we had direct proofs of the connection between very massive stars, their eruptions and type IIn SNe, such as the case of the controversial SN 2009ip. Even if these objects are quite rare, their number has increased in the last couple of years. In this poster I will summarise my work on this topic, showing the most recent object of study and the conclusions from their analysis.

  4. Supernova 2004cr in UGC 11603

    Science.gov (United States)

    Armstrong, M.

    2004-06-01

    Further to IAUC 8357, M. Armstrong, reports his discovery of an apparent supernova (mag 17.8) on unfiltered CCD images taken on June 17.035 and 18.965 UT with a 0.35-m reflector. SN 2004cr is located at R.A. = 20h36m06s.84, Decl. = +63o44'12".4 (equinox 2000.0), which is approximately 45".9 west and 10".6 south of the center of UGC 11603. Nothing was visible at this position on his images taken on 2001 Aug. 5, 31, and 2003 July 13 (limiting mag about 19.5) or on Palomar Sky Survey red and blue plates.

  5. Supernova 2004ci in NGC 5980

    Science.gov (United States)

    Armstrong, M.; Park, S.; Foley, R. J.

    2004-06-01

    Further to IAUC 8349, M. Armstrong reports his discovery, on images taken on June 16.997 UT, of an apparent supernova (mag 17.5) located at R.A. = 15h41m29s.83, Decl. = +15o47'13".1 (equinox 2000.0), which is 10".1 west and 2".3 south of the center of NGC 5980. Nothing was visible at this location on an image taken by Armstrong on 2003 Apr. 8. Further to IAUC 8345 and 8350, S. Park and R. J. Foley also report LOSS observations of SN 2004ci via KAIT images taken on June 15.3 (mag about 17.7) and 17.3 (mag about 17.4), giving position end figures 29s.71, 12".7. A KAIT image taken on June 12.4 showed nothing at this position (limiting mag about 19.0).

  6. Electron Acceleration in Supernovae and Millimeter Perspectives

    Directory of Open Access Journals (Sweden)

    Keiichi Maeda

    2014-12-01

    Full Text Available Supernovae launch a strong shock wave by the interaction of the expanding ejecta and surrounding circumstellar matter (CSM. At the shock, electrons are accelerated to relativistic speed, creating observed synchrotron emissions in radio wavelengths. In this paper, I suggest that SNe (i.e., < 1 year since the explosion provide a unique site to study the electron acceleration mechanism. I argue that the eciency of the acceleration at the young SN shock is much lower than conventionally assumed, and that the electrons emitting in the cm wavelengths are not fully in the Diffusive Shock Acceleration (DSA regime. Thus radio emissions from young SNe record information on the yet-unresolved 'injection' mechanism. I also present perspectives of millimeter (mm observations of SNe - this will provide opportunities to uniquely determine the shock physics and the acceleration efficiency, to test the non-linear DSA mechanism and provide a characteristic electron energy scale with which the DSA start dominating the electron acceleration.

  7. Core-Collapse Supernovae and Gamma-Ray Bursts in TMT Era

    Indian Academy of Sciences (India)

    Existing 8–10 m class telescopes have been helpful to improve our knowledge about core-collapse supernovae, gamma-ray bursts and nature of their progenitors and explosion mechanisms. However, many aspects about these energetic cosmic explosions are still not well-understood and require much bigger telescopes ...

  8. Type Ia supernova rate at a redshift of ~;0.1

    Energy Technology Data Exchange (ETDEWEB)

    Blanc, G.; Afonso, C.; Alard, C.; Albert, J.N.; Aldering, G.; Amadon, A.; Andersen, J.; Ansari, R.; Aubourg, E.; Balland, C.; Bareyre,P.; Beaulieu, J.P.; Charlot, X.; Conley, A.; Coutures, C.; Dahlen, T.; Derue, F.; Fan, X.; Ferlet, R.; Folatelli, G.; Fouque, P.; Garavini, G.; Glicenstein, J.F.; Goldman, B.; Goobar, A.; Gould, A.; Graff, D.; Gros,M.; Haissinski, J.; Hamadache, C.; Hardin, D.; Hook, I.M.; deKat, J.; Kent, S.; Kim, A.; Lasserre, T.; LeGuillou, L.; Lesquoy, E.; Loup, C.; Magneville, C.; Marquette, J.B.; Maurice, E.; Maury, A.; Milsztajn, A.; Moniez, M.; Mouchet, M.; Newberg, H.; Nobili, S.; Palanque-Delabrouille,N.; Perdereau, O.; Prevot, L.; Rahal, Y.R.; Regnault, N.; Rich, J.; Ruiz-Lapuente, P.; Spiro, M.; Tisserand, P.; Vidal-Madjar, A.; Vigroux,L.; Walton, N.A.; Zylberajch, S.

    2004-05-11

    We present the type Ia rate measurement based on two EROS supernova search campaigns (in 1999 and 2000). Sixteen supernovae identified as type Ia were discovered. The measurement of the detection efficiency, using a Monte Carlo simulation, provides the type Ia supernova explosion rate at a redshift {approx} 0.13. The result is 0.125{sub -0.034-0.028}{sup +0.044+0.028} h{sub 70}{sup 2} SNu where 1 SNu = 1 SN/10{sup 10} L{sub {circle_dot}}{sup B}/century. This value is compatible with the previous EROS measurement (Hardin et al. 2000), done with a much smaller sample, at a similar redshift. Comparison with other values at different redshifts suggests an evolution of the type Ia supernova rate.

  9. Toward connecting core-collapse supernova theory with observations

    Science.gov (United States)

    Handy, Timothy A.

    We study the evolution of the collapsing core of a 15 solar mass blue supergiant supernova progenitor from the moment shortly after core bounce until 1.5 seconds later. We present a sample of two- and three-dimensional hydrodynamic models parameterized to match the explosion energetics of supernova SN 1987A. We focus on the characteristics of the flow inside the gain region and the interplay between hydrodynamics, self-gravity, and neutrino heating, taking into account uncertainty in the nuclear equation of state. We characterize the evolution and structure of the flow behind the shock in terms the accretion flow dynamics, shock perturbations, energy transport and neutrino heating effects, and convective and turbulent motions. We also analyze information provided by particle tracers embedded in the flow. Our models are computed with a high-resolution finite volume shock capturing hydrodynamic code. The code includes source terms due to neutrino-matter interactions from a light-bulb neutrino scheme that is used to prescribe the luminosities and energies of the neutrinos emerging from the core of the proto-neutron star. The proto-neutron star is excised from the computational domain, and its contraction is modeled by a time-dependent inner boundary condition. We find the spatial dimensionality of the models to be an important contributing factor in the explosion process. Compared to two-dimensional simulations, our three-dimensional models require lower neutrino luminosities to produce equally energetic explosions. We estimate that the convective engine in our models is 4% more efficient in three dimensions than in two dimensions. We propose that this is due to the difference of morphology of convection between two- and three-dimensional models. Specifically, the greater efficiency of the convective engine found in three-dimensional simulations might be due to the larger surface-to-volume ratio of convective plumes, which aids in distributing energy deposited by

  10. THE VERY YOUNG TYPE Ia SUPERNOVA 2013dy: DISCOVERY, AND STRONG CARBON ABSORPTION IN EARLY-TIME SPECTRA

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, WeiKang; Filippenko, Alexei V.; Nugent, Peter E.; Graham, Melissa; Kelly, Patrick L.; Fox, Ori D.; Shivvers, Isaac; Clubb, Kelsey I.; Li, Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Silverman, Jeffrey M.; Howie Marion, G. [Department of Astronomy, University of Texas, Austin, TX 78712 (United States); Kasen, Daniel [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Wang, Xiaofeng [Department of Physics, Tsinghua University, Beijing 100084 (China); Valenti, Stefano; Howell, D. Andrew [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Ciabattari, Fabrizio [Monte Agliale Observatory, Borgo a Mozzano, Lucca, I-55023 Italy (Italy); Cenko, S. Bradley [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Balam, Dave [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Hsiao, Eric [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Sand, David, E-mail: zwk@astro.berkeley.edu [Physics Department, Texas Tech University, Lubbock, TX 79409 (United States); and others

    2013-11-20

    The Type Ia supernova (SN Ia) 2013dy in NGC 7250 (d ≈ 13.7 Mpc) was discovered by the Lick Observatory Supernova Search. Combined with a prediscovery detection by the Italian Supernova Search Project, we are able to constrain the first-light time of SN 2013dy to be only 0.10 ± 0.05 days (2.4 ± 1.2 hr) before the first detection. This makes SN 2013dy the earliest known detection of an SN Ia. We infer an upper limit on the radius of the progenitor star of R {sub 0} ≲ 0.25 R {sub ☉}, consistent with that of a white dwarf. The light curve exhibits a broken power law with exponents of 0.88 and then 1.80. A spectrum taken 1.63 days after first light reveals a C II absorption line comparable in strength to Si II. This is the strongest C II feature ever detected in a normal SN Ia, suggesting that the progenitor star had significant unburned material. The C II line in SN 2013dy weakens rapidly and is undetected in a spectrum 7 days later, indicating that C II is detectable for only a very short time in some SNe Ia. SN 2013dy reached a B-band maximum of M{sub B} = –18.72 ± 0.03 mag ∼17.7 days after first light.

  11. The Radio Remnant of Supernova 1987A - A Broader View

    Science.gov (United States)

    Zanardo, G.; Staveley-Smith, L.; Ng, C.-Y.; Indebetouw, R.; Matsuura, M.; Gaensler, B. M.; Tzioumis, A. K.

    2017-02-01

    Supernova remnants (SNRs) are powerful particle accelerators. As a supernova (SN) blast wave propagates through the circumstellar medium (CSM), electrons and protons scatter across the shock and gain energy by entrapment in the magnetic field. The accelerated particles generate further magnetic field fluctuations and local amplification, leading to cosmic ray production. The wealth of data from Supernova 1987A is providing a template of the SN-CSM interaction, and an important guide to the radio detection and identification of core-collapse SNe based on their spectral properties. Thirty years after the explosion, radio observations of SNR 1987A span from 70 MHz to 700 GHz. We review extensive observing campaigns with the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/submillimeter Array (ALMA), and follow-ups with other radio telescopes. Observations across the radio spectrum indicate rapid changes in the remnant morphology, while current ATCA and ALMA observations show that the SNR has entered a new evolutionary phase.

  12. Observational Evidence for High Neutronization in Supernova Remnants: Implications for Type Ia Supernova Progenitors

    Energy Technology Data Exchange (ETDEWEB)

    Martínez-Rodríguez, Héctor; Badenes, Carles; Andrews, Brett [Department of Physics and Astronomy and Pittsburgh Particle Physics, Astrophysics and Cosmology Center (PITT PACC), University of Pittsburgh, 3941 O’Hara Street, Pittsburgh, PA 15260 (United States); Yamaguchi, Hiroya [NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Bravo, Eduardo [E.T.S. Arquitectura del Vallès, Universitat Politècnica de Catalunya, Carrer Pere Serra 1-15, E-08173 Sant Cugat del Vallès (Spain); Timmes, F. X. [The Joint Institute for Nuclear Astrophysics (United States); Miles, Broxton J.; Townsley, Dean M. [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL (United States); Piro, Anthony L. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Mori, Hideyuki [CRESST and X-ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 602, Greenbelt, MD 20771 (United States); Park, Sangwook, E-mail: hector.mr@pitt.edu [Department of Physics, University of Texas at Arlington, Box 19059, Arlington, TX 76019 (United States)

    2017-07-01

    The physical process whereby a carbon–oxygen white dwarf explodes as a Type Ia supernova (SN Ia) remains highly uncertain. The degree of neutronization in SN Ia ejecta holds clues to this process because it depends on the mass and the metallicity of the stellar progenitor, and on the thermodynamic history prior to the explosion. We report on a new method to determine ejecta neutronization using Ca and S lines in the X-ray spectra of Type Ia supernova remnants (SNRs). Applying this method to Suzaku data of Tycho, Kepler , 3C 397, and G337.2−0.7 in the Milky Way, and N103B in the Large Magellanic Cloud, we find that the neutronization of the ejecta in N103B is comparable to that of Tycho and Kepler , which suggests that progenitor metallicity is not the only source of neutronization in SNe Ia. We then use a grid of SN Ia explosion models to infer the metallicities of the stellar progenitors of our SNRs. The implied metallicities of 3C 397, G337.2−0.7, and N103B are major outliers compared to the local stellar metallicity distribution functions, indicating that progenitor metallicity can be ruled out as the origin of neutronization for these SNRs. Although the relationship between ejecta neutronization and equivalent progenitor metallicity is subject to uncertainties stemming from the {sup 12}C + {sup 16}O reaction rate, which affects the Ca/S mass ratio, our main results are not sensitive to these details.

  13. Radio emission from embryonic superluminous supernova remnants

    Science.gov (United States)

    Omand, Conor M. B.; Kashiyama, Kazumi; Murase, Kohta

    2018-02-01

    It has been widely argued that Type-I superluminous supernovae (SLSNe-I) are driven by powerful central engines with a long-lasting energy injection after the core-collapse of massive progenitors. One of the popular hypotheses is that the hidden engines are fast-rotating pulsars with a magnetic field of B ˜ 1013-1015 G. Murase, Kashiyama & Mészáros proposed that quasi-steady radio/submm emission from non-thermal electron-positron pairs in nascent pulsar wind nebulae can be used as a relevant counterpart of such pulsar-driven supernovae (SNe). In this work, focusing on the nascent SLSN-I remnants, we examine constraints that can be placed by radio emission. We show that the Atacama Large Millimeter/submillimetre Array can detect the radio nebula from SNe at DL ˜ 1 Gpc in a few years after the explosion, while the Jansky Very Large Array can also detect the counterpart in a few decades. The proposed radio follow-up observation could solve the parameter degeneracy in the pulsar-driven SN model for optical/UV light curves, and could also give us clues to young neutron star scenarios for SLSNe-I and fast radio bursts.

  14. 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.

  15. The direct identification of core-collapse supernova progenitors.

    Science.gov (United States)

    Van Dyk, Schuyler D

    2017-10-28

    To place core-collapse supernovae (SNe) in context with the evolution of massive stars, it is necessary to determine their stellar origins. I describe the direct identification of SN progenitors in existing pre-explosion images, particularly those obtained through serendipitous imaging of nearby galaxies by the Hubble Space Telescope I comment on specific cases representing the various core-collapse SN types. Establishing the astrometric coincidence of a SN with its putative progenitor is relatively straightforward. One merely needs a comparably high-resolution image of the SN itself and its stellar environment to perform this matching. The interpretation of these results, though, is far more complicated and fraught with larger uncertainties, including assumptions of the distance to and the extinction of the SN, as well as the metallicity of the SN environment. Furthermore, existing theoretical stellar evolutionary tracks exhibit significant variations one from the next. Nonetheless, it appears fairly certain that Type II-P (plateau) SNe arise from massive stars in the red supergiant phase. Many of the known cases are associated with subluminous Type II-P events. The progenitors of Type II-L (linear) SNe are less established. Among the stripped-envelope SNe, there are now a number of examples of cool, but not red, supergiants (presumably in binaries) as Type IIb progenitors. We appear now finally to have an identified progenitor of a Type Ib SN, but no known example yet for a Type Ic. The connection has been made between some Type IIn SNe and progenitor stars in a luminous blue variable phase, but that link is still thin, based on direct identifications. Finally, I also describe the need to revisit the SN site, long after the SN has faded, to confirm the progenitor identification through the star's disappearance and potentially to detect a putative binary companion that may have survived the explosion.This article is part of the themed issue 'Bridging the gap: from

  16. Supernova Science Center

    Energy Technology Data Exchange (ETDEWEB)

    S. E. Woosley

    2008-05-05

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

  17. Superluminous Supernovae hydrodynamic models

    Science.gov (United States)

    Orellana, M.

    2017-07-01

    We use our radiation hydrodynamic code in order to simulate magnetar powered Superluminous Supernovae (SLSNe). It is assumed that a central rapidly rotating magnetar deposits all its rotational energy into the ejecta where is added to the usual power. The magnetar luminosity and spin-down timescale are adopted as the free parameters of the model. For the case of ASASSN-15lh, which has been claimed as the most luminous supernova ever discovered, we have found physically plausible magnetar parameters can reproduce the overall shape of the bolometric light curve (LC) provided the progenitor mass is ≍ 8M⊙. The ejecta dynamics of this event shows signs of the magnetar energy input which deviates the expansion from the usually assumed homologous behaviour. Our numerical experiments lead us to conclude that the hydrodynamical modeling is necessary in order to derive the properties of powerful magnetars driving SLSNe.

  18. First-principles study of LaSn3 as an anode for lithium-ion batteries

    Science.gov (United States)

    Shin, Dongwon; Wolverton, Christopher; Vaughey, John; Thackeray, Michael

    2009-03-01

    Using both density functional theory (DFT) calculations and experiment, we investigate the tin-rich intermetallic compound LaSn3 as a possible anode for lithium-ion batteries. We use DFT calculations to compare the relative energies of hypothetical insertion- and displacement-type reactions in an effort to elucidate the energetically-preferred reaction mechanism of Li with LaSn3. From our DFT calculations, we find: (i) lithium insertion reactions with LaSn3 are predicted to be energetically unfavorable and highly unlikely to occur; (ii) in contrast, the energetically preferred reaction is a displacement reaction in which La is partially displaced from LaSn3 to yield La3Sn5 and Li reacts with the residual Sn to form Li17Sn4, corresponding to an electrochemical capacity of 307 mAh/g (iii) this partial displacement reaction is preferred relative to the complete displacement and lithiation of Sn; and (iv) the lithiated-tin compound, Li17Sn4, is energetically more favored than the commonly reported Li22Sn5 composition. Electrochemical and structural data largely confirm the DFT predictions; they demonstrate that lithium reacts with LaSn3 via a displacement reaction to provide a reversible specific capacity of 200-250 mAh/g.

  19. COMPTEL upper limits for the 56Co gamma-ray emission from SN1998bu

    OpenAIRE

    Georgii, R.; Plüschke, S.; Diehl, R.; Lichti, G. G.; Schönfelder, V.; Bloemen, H.; Hermsen, W.; Ryan, J; Bennett, K.

    2002-01-01

    Supernova 1998bu in the galaxy M96 was observed by COMPTEL for a total of 88 days starting 17 days after the explosion. We searched for a signal in the 847 keV and 1238 keV lines of radioactive 56Co from this type Ia supernova. Using several different analysis methods, we did not detect SN1998bu. Our measurements should have been sensitive enough to detect 60Co gamma-rays as predicted from supernova models. Our 2-sigma flux limit is 2.3 10^{-5} photons cm^{-2} s^{-1}; this would correspond to...

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

    Science.gov (United States)

    Ellis, J; Schramm, D N

    1995-01-03

    We examine the possibility that a nearby supernova explosion could have caused one or more of the mass extinctions identified by paleontologists. We discuss the possible rate of such events in the light of the recent suggested identification of Geminga as a supernova remnant less than 100 parsec (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 are discussed. A supernova explosion of the order of 10 pc away could be expected as often as 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 at the "KT boundary." The recent argument that the KT event was exceedingly large and thus quite rare supports the need for other catastrophic events.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J. [European Organization for Nuclear Research, Geneva (Switzerland); Schramm, D.N. [Univ. of Chicago, IL (United States)]|[Fermi National Accelerator Lab., Batavia, IL (United States)

    1995-01-03

    We examine the possibility that a nearby supernova explosion could have caused one or more of the mass extinctions identified by paleontologists. We discuss the possible rate of such events in the light of the recent suggested identification of Geminga as a supernova remnant less than 100 parsec (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 are discussed. A supernova explosion of the order of 10 pc away could be expected as often as 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 at the {open_quotes}KT boundary.{close_quotes} The recent argument that the KT event was exceedingly large and thus quite rare supports the need for other catastrophic events. 24 refs.

  2. 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.

  3. Energetics Conditioning Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Energetics Conditioning Facility is used for long term and short term aging studies of energetic materials. The facility has 10 conditioning chambers of which 2...

  4. IS THERE A HIDDEN HOLE IN TYPE Ia SUPERNOVA REMNANTS?

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Senz, D. [Departament de Fisica i Enginyeria Nuclear, UPC, Compte d' Urgell 187, 08036 Barcelona (Spain); Badenes, C. [School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Serichol, N., E-mail: domingo.garcia@upc.edu, E-mail: carles@astro.tau.ac.il, E-mail: nuria.serichol@upc.edu [Departament de Matematica Aplicada III, Sor Eulalia d' Anzizu, 08034 Barcelona (Spain)

    2012-01-20

    In this paper, we report on the bulk features of the hole carved by the companion star in the material ejected during a Type Ia supernova (SN Ia) explosion. In particular we are interested in the long-term evolution of the hole as well as in its fingerprint in the geometry of the supernova remnant (SNR) after several centuries of evolution, which is a hot topic in current SN Ia studies. We use an axisymmetric smoothed particle hydrodynamics code to characterize the geometric properties of the SNR resulting from the interaction of this ejected material with the ambient medium. Our aim is to use SNR observations to constrain the single degenerate scenario for SN Ia progenitors. Our simulations show that the hole will remain open during centuries, although its partial or total closure at later times due to hydrodynamic instabilities is not excluded. Close to the edge of the hole, the Rayleigh-Taylor instability grows faster, leading to plumes that approach the edge of the forward shock. We also discuss other geometrical properties of the simulations, like the evolution of the contact discontinuity.

  5. [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.

  6. Imaging the Distribution of Iron in a Type Ia Supernova

    Science.gov (United States)

    Fesen, Robert

    2009-07-01

    We know Type Ia supernovae are thermonuclear explosions of CO white dwarfs, but we don't know the specifics of how the nuclear burning proceeds from the core outward to the surface once it starts. Thermonuclear instability in a WD core is thought to start off as a subsonic, turbulent deflagration wave or "burning" wave but then may, at some point, transition into a supernova blast or detonation wave. In such a "delayed detonation" model, differences between normal and subluminous Type Ia SNe reflect differences in the amount of burning that has occurred in the pre-detonation phase. More burning helps to pre-expand the WD before passage of the detontation wave which then lowers the density of the outer layers and, in turn, results in a different element production and internal structure.Directly imaging the 2D chemical distribution of ejecta from a Type Ia SN is actually possible in the case of the subluminous Type Ia SN 1885 which occurred on the near-side of M31's central bulge. The entire 123 year old remnant -- core to outer edge -- is visible via strong near-UV, Ca and Fe line absorptions, and remarkably, is still in near free expansion. This means that elemental stratification seen today is likely to accurately reflect the explosive nucleosynthesis physics.We propose ACS WFC images of SN 1885 to take advantage of this extraordinary situation: Having a young, nearby Type Ia SN remnant visible in silhouette against a galaxy-size light table. The proposed observations will reveal the Fe ejecta distribution, density structure, sphericity, and ionization state as a function of expansion velocity, thereby testing SN Ia explosion models with direct Fe-rich ejecta mapping data.

  7. Late-time spectroscopy of Type Iax Supernovae

    Science.gov (United States)

    Foley, Ryan J.; Jha, Saurabh W.; Pan, Yen-Chen; Zheng, Wei Kang; Bildsten, Lars; Filippenko, Alexei V.; Kasen, Daniel

    2016-09-01

    We examine the late-time (t ≳ 200 d after peak brightness) spectra of Type Iax supernovae (SNe Iax), a low-luminosity, low-energy class of thermonuclear stellar explosions observationally similar to, but distinct from, Type Ia supernovae. We present new spectra of SN 2014dt, resulting in the most complete late-time spectral sequence of an SN Iax. At late times, SNe Iax have generally similar spectra, all with a similar continuum shape and strong forbidden-line emission. However, there is also significant diversity where some SN Iax spectra display narrow P-Cygni features from permitted lines and a continuum indicative of a photosphere at late times in addition to strong narrow (FWHM 6000 km s-1) forbidden lines, and weak narrow forbidden lines, and some SNe Iax have spectra intermediate to these two varieties. We find that SNe Iax with strong broad forbidden lines are more luminous and have higher velocity ejecta at peak brightness. We estimate blackbody and kinematic radii of the late-time photosphere, finding the latter significantly larger than the former. We propose a two-component model that solves this discrepancy and explains the diversity of the late-time spectra of SNe Iax. In this model, the broad forbidden lines originate from the SN ejecta, while the photosphere, P-Cygni lines, and narrow forbidden lines originate from a wind launched from the remnant of the progenitor white dwarf and is driven by the radioactive decay of newly synthesized material left in the remnant. The relative strength of the two components accounts for the diversity of late-time SN Iax spectra. This model also solves the puzzle of a long-lived photosphere and the slow late-time decline of SNe Iax.

  8. VizieR Online Data Catalog: Lick Observatory Supernova Search (LOSS) revisited (Graur+, 2017)

    Science.gov (United States)

    Graur, O.; Bianco, F. B.; Huang, S.; Modjaz, M.; Shivvers, I.; Filippenko, A. V.; Li, W.; Eldridge, J. J.

    2017-10-01

    Most types of supernovae (SNe) have yet to be connected with their progenitor stellar systems. Here, we reanalyze the 10-year SN sample collected during 1998-2008 by the Lick Observatory Supernova Search (LOSS; see Leaman+, 2011, J/MNRAS/412/1419) in order to constrain the progenitors of SNe Ia and stripped-envelope SNe (SE SNe, i.e., SNe IIb, Ib, Ic, and broad-lined Ic). We matched the LOSS galaxy sample with spectroscopy from the Sloan Digital Sky Survey (SDSS) and measured SN rates as a function of galaxy stellar mass, specific star formation rate, and oxygen abundance (metallicity). We find significant correlations between the SN rates and all three galaxy properties. The SN Ia correlations are consistent with other measurements, as well as with our previous explanation of these measurements in the form of a combination of the SN Ia delay-time distribution and the correlation between galaxy mass and age. The ratio between the SE SN and SN II rates declines significantly in low-mass galaxies. This rules out single stars as SE SN progenitors, and is consistent with predictions from binary-system progenitor models. Using well-known galaxy scaling relations, any correlation between the rates and one of the galaxy properties examined here can be expressed as a correlation with the other two. These redundant correlations preclude us from establishing causality-that is, from ascertaining which of the galaxy properties (or their combination) is the physical driver for the difference between the SE SN and SN II rates. We outline several methods that have the potential to overcome this problem in future works. (7 data files).

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

    Science.gov (United States)

    2003-08-01

    1448 and SN 2001el (DSS and NTT/EMMI). PR Photo 24b/03 : Optical spectrum of SN 2001el and fractional polarisation (VLT/FORS) Supernova explosions and cosmic distances During Type Ia supernova events, remnants of stars with an initial mass of up to a few times that of the Sun (so-called "white dwarf stars") explode, leaving nothing behind but a rapidly expanding cloud of "stardust". Type Ia supernovae are apparently quite similar to one another. This provides them a very useful role as "standard candles" that can be used to measure cosmic distances. Their peak brightness rivals that of their parent galaxy, hence qualifying them as prime cosmic yardsticks. Astronomers have exploited this fortunate circumstance to study the expansion history of our Universe. They recently arrived at the fundamental conclusion that the Universe is expanding at an accelerating rate, cf. ESO PR 21/98, December 1998 (see also the Supernova Acceleration Probe web page). The explosion of a white dwarf star In the most widely accepted models of Type Ia supernovae the pre-explosion white dwarf star orbits a solar-like companion star, completing a revolution every few hours. Due to the close interaction, the companion star continuously loses mass, part of which is picked up (in astronomical terminology: "accreted") by the white dwarf. A white dwarf represents the penultimate stage of a solar-type star. The nuclear reactor in its core has run out of fuel a long time ago and is now inactive. However, at some point the mounting weight of the accumulating material will have increased the pressure inside the white dwarf so much that the nuclear ashes in there will ignite and start burning into even heavier elements. This process very quickly becomes uncontrolled and the entire star is blown to pieces in a dramatic event. An extremely hot fireball is seen that often outshines the host galaxy. The shape of the explosion Although all supernovae of Type Ia have quite similar properties, it has never been

  10. Supernova 2010as: the lowest-velocity member of a family of flat-velocity type IIb supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Folatelli, Gastón; Bersten, Melina C.; Nomoto, Ken' ichi [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Kuncarayakti, Hanindyo; Hamuy, Mario [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Olivares Estay, Felipe; Pignata, Giuliano [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Anderson, Joseph P. [European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago (Chile); Holmbo, Simon; Stritzinger, Maximilian [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Maeda, Keiichi [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Morrell, Nidia; Contreras, Carlos; Phillips, Mark M. [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Förster, Francisco [Center for Mathematical Modelling, Universidad de Chile, Avenida Blanco Encalada 2120 Piso 7, Santiago (Chile); Prieto, José Luis [Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Peyton Hall, Princeton, NJ 08544 (United States); Valenti, Stefano [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Goleta, CA 93117 (United States); Afonso, Paulo; Altenmüller, Konrad; Elliott, Jonny, E-mail: gaston.folatelli@ipmu.jp [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße 1, D-85740 Garching (Germany); and others

    2014-09-01

    We present extensive optical and near-infrared photometric and spectroscopic observations of the stripped-envelope supernova SN 2010as. Spectroscopic peculiarities such as initially weak helium features and low expansion velocities with a nearly flat evolution place this object in the small family of events previously identified as transitional Type Ib/c supernovae (SNe). There is ubiquitous evidence of hydrogen, albeit weak, in this family of SNe, indicating that they are in fact a peculiar kind of Type IIb SNe that we name 'flat-velocity' Type IIb. The flat-velocity evolution—which occurs at different levels between 6000 and 8000 km s{sup –1} for different SNe—suggests the presence of a dense shell in the ejecta. Despite the spectroscopic similarities, these objects show surprisingly diverse luminosities. We discuss the possible physical or geometrical unification picture for such diversity. Using archival Hubble Space Telescope images, we associate SN 2010as with a massive cluster and derive a progenitor age of ≈6 Myr, assuming a single star-formation burst, which is compatible with a Wolf-Rayet progenitor. Our hydrodynamical modeling, on the contrary, indicates that the pre-explosion mass was relatively low, ≈4 M {sub ☉}. The seeming contradiction between a young age and low pre-SN mass may be solved by a massive interacting binary progenitor.

  11. Slow-Speed Supernovae from the Palomar Transient Factory: Two Channels

    Science.gov (United States)

    White, Christopher J.; Kasliwal, Mansi M.; Nugent, Peter E.; Gal-Yam, Avishay; Howell, D. Andrew; Sullivan, Mark; Goobar, Ariel; Piro, Anthony L.; Kulkarni, Shrinivas R.; Bloom, Joshua S.; hide

    2014-01-01

    Since the discovery of the unusual prototype SN 2002cx, the eponymous class of low-velocity, hydrogen-poor supernovae has grown to include at most another two dozen members identified from several heterogeneous surveys, in some cases ambiguously. Here we present the results of a systematic study of 1077 hydrogen-poor supernovae discovered by the Palomar Transient Factory, leading to nine new members of this peculiar class. Moreover we find there are two distinct subclasses based on their spectroscopic, photometric, and host galaxy properties: The "SN 2002cx-like" supernovae tend to be in later-type or more irregular hosts, have more varied and generally dimmer luminosities, have longer rise times, and lack a Ti II trough when compared to the \\SN 2002es-like" supernovae. None of our objects show helium, and we counter a previous claim of two such events. We also find that these transients comprise 5.6+17 -3:7% (90% confidence) of all SNe Ia, lower compared to earlier estimates. Combining our objects with the literature sample, we propose that these subclasses have two distinct physical origins.

  12. A massive star origin for an unusual helium-rich supernova in an elliptical galaxy.

    Science.gov (United States)

    Kawabata, K S; Maeda, K; Nomoto, K; Taubenberger, S; Tanaka, M; Deng, J; Pian, E; Hattori, T; Itagaki, K

    2010-05-20

    The unusual helium-rich (type Ib) supernova SN 2005E is distinguished from all supernovae hitherto observed by its faint and rapidly fading light curve, prominent calcium lines in late-phase spectra and lack of any mark of recent star formation near the supernova location. These properties are claimed to be explained by a helium detonation in a thin surface layer of an accreting white dwarf. Here we report that the observed properties of SN 2005cz, which appeared in an elliptical galaxy, resemble those of SN 2005E. We argue that these properties are best explained by a core-collapse supernova at the low-mass end (8-12 solar masses) of the range of massive stars that explode. Such a low-mass progenitor lost its hydrogen-rich envelope through binary interaction, had very thin oxygen-rich and silicon-rich layers above the collapsing core, and accordingly ejected a very small amount of radioactive (56)Ni and oxygen. Although the host galaxy NGC 4589 is an elliptical, some studies have revealed evidence of recent star-formation activity, consistent with the core-collapse model.

  13. Determination of Primordial Metallicity and Mixing in the Type IIP Supernova 1993W

    Energy Technology Data Exchange (ETDEWEB)

    Baron, E.; Nugent, Peter E.; Branch, David; Hauschildt, Peter H.; Turatto, M.; Cappellaro, E.

    2002-12-11

    We present the results of a large grid of synthetic spectra and compare them to early spectroscopic observations of SN 1993W. This supernova was discovered close to its explosion date and at a recession velocity of 5400 km/s is located in the Hubble flow. We focus here on two early spectra that were obtained approximately 5 and 9 days after explosion. We parameterize the outer supernova envelope as a power-law density profile in homologous expansion. In order to extract information on the value of the parameters a large number of models was required. We show that very early spectra combined with detailed models can provide constraints on the value of the power law index, the ratio of hydrogen to helium in the surface of the progenitor, the progenitor metallicity and the amount of radioactive nickel mixed into the outer envelope of the supernova. The spectral fits reproduce the observed spectra exceedingly well. The spectral results combined with the early photometry predict that the explosion date was 4.7 {+-} 0.7 days before the first spectrum was obtained. The ability to obtain the metallicity from early spectra make SN IIP attractive probes of chemical evolution in the universe and by showing that we have the ability to pin down the parameters of the progenitor and mixing during the supernova explosion, it is likely to make SN IIP useful cosmological distance indicators which are at the same time complementary to SNe Ia.

  14. First SN Discoveries from the Dark Energy Survey

    Science.gov (United States)

    Abbott, T.; Abdalla, F.; Achitouv, I.; Ahn, E.; Aldering, G.; Allam, S.; Alonso, D.; Amara, A.; Annis, J.; Antonik, M.; Aragon-Salamanca, A.; Armstrong, R.; Ashall, C.; Asorey, J.; Bacon, D.; Balbinot, E.; Banerji, M.; Barbary, K.; Barkhouse, W.; Baruah, L.; Bauer, A.; Bechtol, K.; Becker, M.; Bender, R.; Benoist, C.; Benoit-Levy, A.; Bernardi, M.; Bernstein, G.; Bernstein, J. P.; Bernstein, R.; Bertin, E.; Beynon, E.; Bhattacharya, S.; Biesiadzinski, T.; Biswas, R.; Blake, C.; Bloom, J. S.; Bocquet, S.; Brandt, C.; Bridle, S.; Brooks, D.; Brown, P. J.; Brunner, R.; Buckley-Geer, E.; Burke, D.; Burkert, A.; Busha, M.; Campa, J.; Campbell, H.; Cane, R.; Capozzi, D.; Carlstrom, J.; Carnero Rosell, A.; Carollo, M.; Carrasco-Kind, M.; Carretero, J.; Carter, M.; Casas, R.; Castander, F. J.; Chen, Y.; Chiu, I.; Chue, C.; Clampitt, J.; Clerkin, L.; Cohn, J.; Colless, M.; Copeland, E.; Covarrubias, R. A.; Crittenden, R.; Crocce, M.; Cunha, C.; da Costa, L.; d'Andrea, C.; Das, S.; Das, R.; Davis, T. M.; Deb, S.; DePoy, D.; Derylo, G.; Desai, S.; de Simoni, F.; Devlin, M.; Diehl, H. T.; Dietrich, J.; Dodelson, S.; Doel, P.; Dolag, K.; Efstathiou, G.; Eifler, T.; Erickson, B.; Eriksen, M.; Estrada, J.; Etherington, J.; Evrard, A.; Farrens, S.; Fausti Neto, A.; Fernandez, E.; Ferreira, P. C.; Finley, D.; Fischer, J. A.; Flaugher, B.; Fosalba, P.; Frieman, J.; Furlanetto, C.; Garcia-Bellido, J.; Gaztanaga, E.; Gelman, M.; Gerdes, D.; Giannantonio, T.; Gilhool, S.; Gill, M.; Gladders, M.; Gladney, L.; Glazebrook, K.; Gray, M.; Gruen, D.; Gruendl, R.; Gupta, R.; Gutierrez, G.; Habib, S.; Hall, E.; Hansen, S.; Hao, J.; Heitmann, K.; Helsby, J.; Henderson, R.; Hennig, C.; High, W.; Hirsch, M.; Hoffmann, K.; Holhjem, K.; Honscheid, K.; Host, O.; Hoyle, B.; Hu, W.; Huff, E.; Huterer, D.; Jain, B.; James, D.; Jarvis, M.; Jarvis, M. J.; Jeltema, T.; Johnson, M.; Jouvel, S.; Kacprzak, T.; Karliner, I.; Katsaros, J.; Kent, S.; Kessler, R.; Kim, A.; Kim-Vy, T.; King, L.; Kirk, D.; Kochanek, C.; Kopp, M.; Koppenhoefer, J.; Kovacs, E.; Krause, E.; Kravtsov, A.; Kron, R.; Kuehn, K.; Kuemmel, M.; Kuhlmann, S.; Kunder, A.; Kuropatkin, N.; Kwan, J.; Lahav, O.; Leistedt, B.; Levi, M.; Lewis, P.; Liddle, A.; Lidman, C.; Lilly, S.; Lin, H.; Liu, J.; Lopez-Arenillas, C.; Lorenzon, W.; LoVerde, M.; Ma, Z.; Maartens, R.; Maccrann, N.; Macri, L.; Maia, M.; Makler, M.; Manera, M.; Maraston, C.; March, M.; Markovic, K.; Marriner, J.; Marshall, J.; Marshall, S.; Martini, P.; Marti Sanahuja, P.; Mayers, J.; McKay, T.; McMahon, R.; Melchior, P.; Merritt, K. W.; Merson, A.; Miller, C.; Miquel, R.; Mohr, J.; Moore, T.; Mortonson, M.; Mosher, J.; Mould, J.; Mukherjee, P.; Neilsen, E.; Ngeow, C.; Nichol, R.; Nidever, D.; Nord, B.; Nugent, P.; Ogando, R.; Old, L.; Olsen, J.; Ostrovski, F.; Paech, K.; Papadopoulos, A.; Papovich, C.; Patton, K.; Peacock, J.; Pellegrini, P. S. S.; Peoples, J.; Percival, W.; Perlmutter, S.; Petravick, D.; Plazas, A.; Ponce, R.; Poole, G.; Pope, A.; Refregier, A.; Reyes, R.; Ricker, P.; Roe, N.; Romer, K.; Roodman, A.; Rooney, P.; Ross, A.; Rowe, B.; Rozo, E.; Rykoff, E.; Sabiu, C.; Saglia, R.; Sako, M.; Sanchez, A.; Sanchez, C.; Sanchez, E.; Sanchez, J.; Santiago, B.; Saro, A.; Scarpine, V.; Schindler, R.; Schmidt, B. P.; Schmitt, R. L.; Schubnell, M.; Seitz, S.; Senger, R.; Sevilla, I.; Sharp, R.; Sheldon, E.; Sheth, R.; Smith, R. C.; Smith, M.; Snigula, J.; Soares-Santos, M.; Sobreira, F.; Song, J.; Soumagnac, M.; Spinka, H.; Stebbins, A.; Stoughton, C.; Suchyta, E.; Suhada, R.; Sullivan, M.; Sun, F.; Suntzeff, N.; Sutherland, W.; Swanson, M. E. C.; Sypniewski, A. J.; Szepietowski, R.; Talaga, R.; Tarle, G.; Tarrant, E.; Balan, S. Thaithara; Thaler, J.; Thomas, D.; Thomas, R. C.; Tucker, D.; Uddin, S. A.; Ural, S.; Vikram, V.; Voigt, L.; Walker, A. R.; Walker, T.; Wechsler, R.; Weinberg, D.; Weller, J.; Wester, W.; Wetzstein, M.; White, M.; Wilcox, H.; Wilman, D.; Yanny, B.; Young, J.; Zablocki, A.; Zenteno, A.; Zhang, Y.; Zuntz, J.

    2012-12-01

    The Dark Energy Survey (DES) report the discovery of the first set of supernovae (SN) from the project. Images were observed as part of the DES Science Verification phase using the newly-installed 570-Megapixel Dark Energy Camera on the CTIO Blanco 4-m telescope by observers J. Annis, E. Buckley-Geer, and H. Lin. SN observations are planned throughout the observing campaign on a regular cadence of 4-6 days in each of the ten 3-deg2 fields in the DES griz filters.

  15. Emission of SN 1006 produced by accelerated cosmic rays

    OpenAIRE

    Berezhko, E. G.; Ksenofontov, L. T.; Voelk, H. J.

    2002-01-01

    The nonlinear kinetic model of cosmic ray (CR) acceleration in supernova remnants (SNRs) is used to describe the properties of the remnant of SN 1006. It is shown, that the theory fits the existing data in a satisfactory way within a set of parameters which is consistent with the idea that SN 1006 is a typical source of Galactic CR nucleons, although not necessarily of CR electrons. The adjusted parameters are those that are not very well determined by present theory or not directly amenable ...

  16. VizieR Online Data Catalog: UBVRIz light curves of 51 Type II supernovae (Galbany+, 2016)

    Science.gov (United States)

    Galbany, L.; Hamuy, M.; Phillips, M. M.; Suntzeff, N. B.; Maza, J.; de Jaeger, T.; Moraga, T.; Gonzalez-Gaitan, S.; Krisciunas, K.; Morrell, N. I.; Thomas-Osip, J.; Krzeminski, W.; Gonzalez, L.; Antezana, R.; Wishnjewski, M.; McCarthy, P.; Anderson, J. P.; Gutierrez, C. P.; Stritzinger, M.; Folatelli, G.; Anguita, C.; Galaz, G.; Green, E. M.; Impey, C.; Kim, Y.-C.; Kirhakos, S.; Malkan, M. A.; Mulchaey, J. S.; Phillips, A. C.; Pizzella, A.; Prosser, C. F.; Schmidt, B. P.; Schommer, R. A.; Sherry, W.; Strolger, L.-G.; Wells, L. A.; Williger, G. M.

    2016-08-01

    This paper presents a sample of multi-band, visual-wavelength light curves of 51 type II supernovae (SNe II) observed from 1986 to 2003 in the course of four different surveys: the Cerro Tololo Supernova Survey, the Calan Tololo Supernova Program (C&T), the Supernova Optical and Infrared Survey (SOIRS), and the Carnegie Type II Supernovae Survey (CATS). Near-infrared photometry and optical spectroscopy of this set of SNe II will be published in two companion papers. A list of the SNe II used in this study is presented in Table1. The first object in our list is SN 1986L and it is the only SN observed with photoelectric techniques (by M.M.P and S.K., using the Cerro Tololo Inter-American Observatory (CTIO) 0.9m equipped with a photometer and B and V filters). The remaining SNe were observed using a variety of telescopes equipped with CCD detectors and UBV(RI)KCz filters (see Table5). The magnitudes for the photometric sequences of the 51 SNe II are listed in Table4. In every case, these sequences were derived from observations of Landolt standards (see Appendix D in Hamuy et al. 2001ApJ...558..615H for the definition of the z band and Stritzinger et al. 2002AJ....124.2100S for the description of the z-band standards). Table5 lists the resulting UBVRIz magnitudes for the 51 SNe. (3 data files).

  17. No Escape from the Supernova! Magnetic Imprisonment of Dusty Pinballs by a Supernova Remnant arXiv

    CERN Document Server

    Fry, Brian J.; Ellis, John R.

    Motivated by recent measurements of deposits of $^{60}$Fe on the ocean floor and the lunar surface, we model the transport of dust grains containing $^{60}$Fe from a near-Earth (i.e., within 100 pc) supernova (SN). We inject dust grains into the environment of a SN remnant (SNR) and trace their trajectories using a magnetohydrodynamic description. We assume the interstellar medium (ISM) magnetic fields are turbulent, and are amplified by the SNR shock, while the SN wind and ejecta fields are negligible. We examine the various influences on the dust grains within the SNR to determine when/if the dust decouples from the plasma, how much it is sputtered, and where within the SNR the dust grains are located. We find that Rayleigh-Taylor instabilities are important for dust survival, as they influence the location of the SN's reverse shock. We find that the presence of a magnetic field within the shocked ISM material limits the passage of SN dust grains, with the field either reflecting or trapping the grains with...

  18. 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 the entire maximum-light SN Ia spectral energy distribution. Since the UV region of an SN Ia spectrum is extremely sensitive to the composition of the outer layers of the explosion, which are transparent at longer wavelengths, this unprecedented spectrum can provide strong constraints on the composition of the SN ejecta, and similarly the SN explosion and progenitor system. SN 2011iv is spectroscopically normal, but has a relatively fast decline ({Delta}m{sub 15}(B) = 1.69 {+-} 0.05 mag). We compare SN 2011iv to other SNe Ia with UV spectra near maximum light and examine trends between UV spectral properties, light-curve shape, and ejecta velocity. We tentatively find that SNe with similar light-curve shapes but different ejecta velocities have similar UV spectra, while those with similar ejecta velocities but different light-curve shapes have very different UV spectra. Through a comparison with explosion models, we find that both a solar-metallicity W7 and a zero-metallicity delayed-detonation model provide a reasonable fit to the spectrum of SN 2011iv from the UV to the NIR.

  19. Gravitational Lensing of Supernova Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Mena, Olga; /Fermilab /Rome U.; Mocioiu, Irina; /Penn State U.; Quigg, Chris; /Fermilab

    2006-10-01

    The black hole at the center of the galaxy is a powerful lens for supernova neutrinos. In the very special circumstance of a supernova near the extended line of sight from Earth to the galactic center, lensing could dramatically enhance the neutrino flux at Earth and stretch the neutrino pulse.

  20. Pulsar/Supernova Remnant Associations

    Science.gov (United States)

    Kaspi, Victoria M.

    1996-01-01

    We list and review proposed pulsar/supernova remnant associations, summarize recent highlights in the field, including searches for young pulsars, searches for remnants, recent studies of previously proposed associations, and attempts at pulsar/remnant association synthesis. we argue that most proposed pulsar/supernova remnant associations require additional investigation before they can be considered secure, and we suggest directions for future work.

  1. The Lick Observatory Supernova Search

    OpenAIRE

    Li, W.D.; Filippenko, A. V.; Treffers, R. R.; Friedman, A.; Halderson, E.; Johnson, R A; King, J. Y.; Modjaz, M.; Papenkova, M.; Sato, Y.; Shefler, T.

    1999-01-01

    We report here the current status of the Lick Observatory Supernova Search (LOSS) with the Katman Automatic Imaging Telescope (KAIT). The progress on both the hardware and the software of the system is described, and we present a list of recent discoveries. LOSS is the world' most successful search engine for nearby supernovae.

  2. A New Method to Constrain Supernova Fractions Using X-ray Observations of Clusters of Galaxies

    Science.gov (United States)

    Bulbul, Esra; Smith, Randall K.; Loewenstein, Michael

    2012-01-01

    Supernova (SN) explosions enrich the intracluster medium (ICM) both by creating and dispersing metals. We introduce a method to measure the number of SNe and relative contribution of Type Ia supernovae (SNe Ia) and core-collapse supernovae (SNe cc) by directly fitting X-ray spectral observations. The method has been implemented as an XSPEC model called snapec. snapec utilizes a single-temperature thermal plasma code (apec) to model the spectral emission based on metal abundances calculated using the latest SN yields from SN Ia and SN cc explosion models. This approach provides a self-consistent single set of uncertainties on the total number of SN explosions and relative fraction of SN types in the ICM over the cluster lifetime by directly allowing these parameters to be determined by SN yields provided by simulations. We apply our approach to XMM-Newton European Photon Imaging Camera (EPIC), Reflection Grating Spectrometer (RGS), and 200 ks simulated Astro-H observations of a cooling flow cluster, A3112.We find that various sets of SN yields present in the literature produce an acceptable fit to the EPIC and RGS spectra of A3112. We infer that 30.3% plus or minus 5.4% to 37.1% plus or minus 7.1% of the total SN explosions are SNe Ia, and the total number of SN explosions required to create the observed metals is in the range of (1.06 plus or minus 0.34) x 10(exp 9), to (1.28 plus or minus 0.43) x 10(exp 9), fromsnapec fits to RGS spectra. These values may be compared to the enrichment expected based on well-established empirically measured SN rates per star formed. The proportions of SNe Ia and SNe cc inferred to have enriched the ICM in the inner 52 kiloparsecs of A3112 is consistent with these specific rates, if one applies a correction for the metals locked up in stars. At the same time, the inferred level of SN enrichment corresponds to a star-to-gas mass ratio that is several times greater than the 10% estimated globally for clusters in the A3112 mass range.

  3. A NEW METHOD TO CONSTRAIN SUPERNOVA FRACTIONS USING X-RAY OBSERVATIONS OF CLUSTERS OF GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Bulbul, Esra; Smith, Randall K. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Loewenstein, Michael, E-mail: ebulbul@cfa.harvard.edu [CRESST and X-Ray Astrophysics Laboratory, NASA/GSFC, Greenbelt, MD 20771 (United States)

    2012-07-01

    Supernova (SN) explosions enrich the intracluster medium (ICM) both by creating and dispersing metals. We introduce a method to measure the number of SNe and relative contribution of Type Ia supernovae (SNe Ia) and core-collapse supernovae (SNe cc) by directly fitting X-ray spectral observations. The method has been implemented as an XSPEC model called snapec. snapec utilizes a single-temperature thermal plasma code (apec) to model the spectral emission based on metal abundances calculated using the latest SN yields from SN Ia and SN cc explosion models. This approach provides a self-consistent single set of uncertainties on the total number of SN explosions and relative fraction of SN types in the ICM over the cluster lifetime by directly allowing these parameters to be determined by SN yields provided by simulations. We apply our approach to XMM-Newton European Photon Imaging Camera (EPIC), Reflection Grating Spectrometer (RGS), and 200 ks simulated Astro-H observations of a cooling flow cluster, A3112. We find that various sets of SN yields present in the literature produce an acceptable fit to the EPIC and RGS spectra of A3112. We infer that 30.3% {+-} 5.4% to 37.1% {+-} 7.1% of the total SN explosions are SNe Ia, and the total number of SN explosions required to create the observed metals is in the range of (1.06 {+-} 0.34) Multiplication-Sign 10{sup 9} to (1.28 {+-} 0.43) Multiplication-Sign 10{sup 9}, from snapec fits to RGS spectra. These values may be compared to the enrichment expected based on well-established empirically measured SN rates per star formed. The proportions of SNe Ia and SNe cc inferred to have enriched the ICM in the inner 52 kpc of A3112 is consistent with these specific rates, if one applies a correction for the metals locked up in stars. At the same time, the inferred level of SN enrichment corresponds to a star-to-gas mass ratio that is several times greater than the 10% estimated globally for clusters in the A3112 mass range.

  4. A New Method to Constrain Supernova Fractions Using X-Ray Observations of Clusters of Galaxies

    Science.gov (United States)

    Bulbul, Esra; Smith, Randall K.; Loewenstein, Michael

    2012-07-01

    Supernova (SN) explosions enrich the intracluster medium (ICM) both by creating and dispersing metals. We introduce a method to measure the number of SNe and relative contribution of Type Ia supernovae (SNe Ia) and core-collapse supernovae (SNe cc) by directly fitting X-ray spectral observations. The method has been implemented as an XSPEC model called snapec. snapec utilizes a single-temperature thermal plasma code (apec) to model the spectral emission based on metal abundances calculated using the latest SN yields from SN Ia and SN cc explosion models. This approach provides a self-consistent single set of uncertainties on the total number of SN explosions and relative fraction of SN types in the ICM over the cluster lifetime by directly allowing these parameters to be determined by SN yields provided by simulations. We apply our approach to XMM-Newton European Photon Imaging Camera (EPIC), Reflection Grating Spectrometer (RGS), and 200 ks simulated Astro-H observations of a cooling flow cluster, A3112. We find that various sets of SN yields present in the literature produce an acceptable fit to the EPIC and RGS spectra of A3112. We infer that 30.3% ± 5.4% to 37.1% ± 7.1% of the total SN explosions are SNe Ia, and the total number of SN explosions required to create the observed metals is in the range of (1.06 ± 0.34) × 109 to (1.28 ± 0.43) × 109, from snapec fits to RGS spectra. These values may be compared to the enrichment expected based on well-established empirically measured SN rates per star formed. The proportions of SNe Ia and SNe cc inferred to have enriched the ICM in the inner 52 kpc of A3112 is consistent with these specific rates, if one applies a correction for the metals locked up in stars. At the same time, the inferred level of SN enrichment corresponds to a star-to-gas mass ratio that is several times greater than the 10% estimated globally for clusters in the A3112 mass range.

  5. Hubble Space Telescope Observations of the Afterglow, Supernova and Host Galaxy Associated with the Extremely Bright GRB 130427A

    Science.gov (United States)

    Levan, A.J.; Tanvir, N. R.; Fruchter, A. S.; Hjorth, J.; Pian, E.; Mazzali, P.; Hounsell, R. A.; Perley, D. A.; Cano, Z.; Graham, J.; hide

    2014-01-01

    We present Hubble Space Telescope (HST) observations of the exceptionally bright and luminous Swift gamma-ray burst, GRB 130427A. At z=0.34 this burst affords an excellent opportunity to study the supernova and host galaxy associated with an intrinsically extremely luminous burst (E(sub iso) greater than 10(exp 54) erg): more luminous than any previous GRB with a spectroscopically associated supernova. We use the combination of the image quality, UV capability and and invariant PSF of HST to provide the best possible separation of the afterglow, host and supernova contributions to the observed light approximately 17 rest-frame days after the burst utilising a host subtraction spectrum obtained 1 year later. Advanced Camera for Surveys (ACS) grism observations show that the associated supernova, SN 2013cq, has an overall spectral shape and luminosity similar to SN 1998bw (with a photospheric velocity, vph approximately 15,000 kilometers per second). The positions of the bluer features are better matched by the higher velocity SN 2010bh (vph approximately 30,000 kilometers per second), but SN 2010bh (vph approximately 30,000 kilometers per second but this SN is significantly fainter, and fails to reproduce the overall spectral shape, perhaps indicative of velocity structure in the ejecta. We find that the burst originated approximately 4 kpc from the nucleus of a moderately star forming (1 Solar Mass yr(exp-1)), possibly interacting disc galaxy. The absolute magnitude, physical size and morphology of this galaxy, as well as the location of the GRB within it are also strikingly similar to those of GRB980425SN 1998bw. The similarity of supernovae and environment from both the most luminous and least luminous GRBs suggests broadly similar progenitor stars can create GRBs across six orders of magnitude in isotropic energy.

  6. Medicina-Noto VLBI observation of SN2013ej

    Science.gov (United States)

    Sokolovsky, K.; Giroletti, M.; Stagni, M.; Nanni, M.; Mahabal, A.

    2013-08-01

    We used the 32m radio telescopes of Istituto di Radioastronomia (INAF-IRA) in Medicina and Noto as a two-element very long baseline interferometer to search for a possible radio counterpart of SN2013ej, a type IIP supernova (CBET #3606, ATel #5228, #5229, #5230, #5237, #5243) in M74. The observations were conducted at 6.7 GHz on 2013 July 31.3 UT, 6 days after the first optical detection reported in CBET #3609.

  7. Cosmic Ray Production in Supernovae

    Science.gov (United States)

    Bykov, A. M.; Ellison, D. C.; Marcowith, A.; Osipov, S. M.

    2018-02-01

    We give a brief review of the origin and acceleration of cosmic rays (CRs), emphasizing the production of CRs at different stages of supernova evolution by the first-order Fermi shock acceleration mechanism. We suggest that supernovae with trans-relativistic outflows, despite being rather rare, may accelerate CRs to energies above 10^{18} eV over the first year of their evolution. Supernovae in young compact clusters of massive stars, and interaction powered superluminous supernovae, may accelerate CRs well above the PeV regime. We discuss the acceleration of the bulk of the galactic CRs in isolated supernova remnants and re-acceleration of escaped CRs by the multiple shocks present in superbubbles produced by associations of OB stars. The effects of magnetic field amplification by CR driven instabilities, as well as superdiffusive CR transport, are discussed for nonthermal radiation produced by nonlinear shocks of all speeds including trans-relativistic ones.

  8. Classification of Gaia17czt as a supernova

    Science.gov (United States)

    Dennefeld, M.

    2017-11-01

    M. Dennefeld (IAP-Paris and UPMC) reports observations of Gaia supernovae candidates with the SAAO 74" telescope equiped with the SpUpNIC spectrograph. Observations during the night of Nov.25 covered the range 3900-9300 A. and the spectral resolution was 5.8 A. Classifications were made with the help of GELATO (Harutyunyan et al. 2008, A & A, 488, 383) Gaia17czt (=AT2017ijr) is classified as a SN Ia around maximum, with an uncertainty of plus minus a few days.

  9. The Data Release of the Sloan Digital Sky Survey-II Supernova Survey

    DEFF Research Database (Denmark)

    Sako, Masao; Bassett, Bruce; C. Becker, Andrew

    2014-01-01

    This paper describes the data release of the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey conducted between 2005 and 2007. Light curves, spectra, classifications, and ancillary data are presented for 10,258 variable and transient sources discovered through repeat ugriz imaging of SDSS......, making this the largest sample of supernova candidates ever compiled. We present a new method for SN host-galaxy identification and derive host-galaxy properties including stellar masses, star-formation rates, and the average stellar population ages from our SDSS multi-band photometry. We derive SALT2...

  10. ASASSN-17ka: Discovery of A Probable Supernova in ESO 244-G 019

    Science.gov (United States)

    Monard, L. A. G.; Brimacombe, J.; Brown, J. S.; Stanek, K. Z.; Holoien, T. W.-S.; Kochanek, C. S.; Shields, J.; Thompson, T. A.; Shappee, B. J.; Prieto, J. L.; Bersier, D.; Dong, Subo; Bose, S.; Chen, Ping; Bock, G.; Fernandez, J. M.; Kiyota, S.; Masi, G.; Post, R. S.

    2017-07-01

    During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014), using data from the quadruple 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy ESO 244-G 019. ASASSN-17ka (AT 2017frr) was discovered in images obtained on UT 2017-07-27.23 at V 16.5 mag. We also detect the object in images obtained on UT 2017-07-24.24 (V 16.6), UT 2017-07-29.23 (V 16.0), and UT 2017-07-30.23 (V 16.5).

  11. ASASSN-17bu: Discovery of A Probable Supernova in ESO 375-G 018

    Science.gov (United States)

    Bock, G.; Brown, J. S.; Stanek, K. Z.; Holoien, T. W.-S.; Kochanek, C. S.; Shields, J.; Thompson, T. A.; Shappee, B. J.; Prieto, J. L.; Bersier, D.; Dong, Subo; Bose, S.; Chen, Ping; Brimacombe, J.; Cruz, I.; Fernandez, J. M.; Kiyota, S.; Koff, R. A.; Krannich, G.; Masi, G.; Nicholls, B.; Post, R. S.; Stone, G.

    2017-02-01

    During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from the quadruple 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy ESO 375-G 018. ASASSN-17bu (AT 2017yv) was discovered in images obtained on UT 2017-01-31.19 at V 16.6 mag. We also detect the object in images obtained on UT 2017-01-29.21 (V 17.1).

  12. Spallation reactions in shock waves at supernova explosions and related problems

    Science.gov (United States)

    Ustinova, G. K.

    2013-05-01

    The isotopic anomalies of some extinct radionuclides testify to the outburst of a nearby supernova just before the collapse of the protosolar nebula, and to the fact that the supernova was Sn Ia, i.e. the carbon-detonation supernova. A key role of spallation reactions in the formation of isotopic anomalies in the primordial matter of the Solar System is revealed. It is conditioned by the diffusive acceleration of particles in the explosive shock waves, which leads to the amplification of rigidity of the energy spectrum of particles and its enrichment with heavier ions. The quantitative calculations of such isotopic anomalies of many elements are presented. It is well-grounded that the anomalous Xe- HL in meteoritic nanodiamonds was formed simultaneously with nanodiamonds themselves during the shock wave propagation at the Sn Ia explosion. The possible effects of shock wave fractionation of noble gases in the atmosphere of planets are considered. The origin of light elements Li, Be and B in spallation reactions, predicted by Fowler in the middle of the last century, is argued. All the investigated isotopic anomalies give the evidence for the extremely high magneto- hydrodynamics (MHD) conditions at the initial stage of free expansion of the explosive shock wave from Sn Ia, which can be essential in solution of the problem of origin of cosmic rays. The specific iron-enriched matter of Sn Ia and its MHD-separation in turbulent processes must be taking into account in the models of origin of the Solar System.

  13. Nuclear Physics and Supernovae

    CERN Document Server

    Austin, S M

    1999-01-01

    At the end of the life of a massive star, its iron core collapses under the unopposed attraction of gravity and initiates the supernova process. A violent explosion ensues and blows off the surface layers of the star, leaving behind a neutron star or a black hole. Both the nature of the collapse and nucleosynthesis by the r-process that synthesizes half of the heavier elements, depend upon the strengths of Gamow Teller transitions in the nuclei involved: those with masses near iron and larger. We will discuss progress made obtaining the needed strengths, with special attention to data on radioactive nuclei and how one may obtain it using radioactive beams.

  14. On luminous blue variables as the progenitors of core-collapse supernovae, especially Type IIn supernovae

    Science.gov (United States)

    Dwarkadas, V. V.

    2011-04-01

    Luminous blue variable (LBV) stars are very massive, luminous, unstable stars that suffer frequent eruptions. In the last few years, these stars have been proposed as the direct progenitors of some core-collapse supernovae (SNe), particularly Type IIn SNe, in conflict with stellar evolution theory. In this paper we investigate various scenarios wherein LBV stars have been suggested as the immediate progenitors of SNe. Many of these suggestions stem from the fact that the SNe appear to be expanding in a high-density medium, which has been interpreted as resulting from a wind with a high mass-loss rate. Others arise due to perceived similarities between the SN characteristics and those of LBVs. Only in the case of SN 2005gl do we find a valid possibility for an LBV-like progenitor. Other scenarios encounter various levels of difficulty. The evidence that points to LBVs as direct core-collapse SNe progenitors is far from convincing. High mass-loss rates are often deduced by making assumptions regarding the wind parameters, which are contradicted by the results themselves. A high density need not necessarily imply a high wind mass-loss rate: wind shocks sweeping up the surrounding medium may give a high-density shell with a low associated wind mass-loss rate. High densities may also arise due to wind clumps, or due to a previous LBV phase before the SN explodes as a WolfRayet (WR) star. Some Type IIn SNe appear to signify more a phase in the life of an SN than a class of SNe, and may arise from more than one type of progenitor. A WR phase that lasts for a few thousand years or less could be one of the more probable progenitors of Type IIns, and channels for creating short-lived WR phases are briefly discussed.

  15. Neutrino signature of supernova hydrodynamical instabilities in three dimensions.

    Science.gov (United States)

    Tamborra, Irene; Hanke, Florian; Müller, Bernhard; Janka, Hans-Thomas; Raffelt, Georg

    2013-09-20

    The first full-scale three-dimensional core-collapse supernova (SN) simulations with sophisticated neutrino transport show pronounced effects of the standing accretion shock instability (SASI) for two high-mass progenitors (20 and 27 M([Symbol: see text])). In a low-mass progenitor (11.2 M([Symbol: see text])), large-scale convection is the dominant nonradial hydrodynamic instability in the postshock accretion layer. The SASI-associated modulation of the neutrino signal (80 Hz in our two examples) will be clearly detectable in IceCube or the future Hyper-Kamiokande detector, depending on progenitor properties, distance, and observer location relative to the main SASI sloshing direction. The neutrino signal from the next galactic SN can, therefore, diagnose the nature of the hydrodynamic instability.

  16. On the progenitor of the Type Ibc supernova 2012fh

    Science.gov (United States)

    Johnson, Samson A.; Kochanek, C. S.; Adams, S. M.

    2017-12-01

    Little is observationally known about the progenitors of Type Ibc supernovae (SNe) or the typical activity of SNe progenitors in their final years. Here, we analyze deep Large Binocular Telescope imaging data spanning the 4 years before and after the Type Ic SN 2012fh using difference imaging. We place 1$\\sigma$ upper limits on the detection of the progenitor star at $M_R>-4.0$, $M_V>-3.8$, $M_B>-3.1$, and $M_U>-3.8$ mag. These limits are the tightest placed on a Type Ic SNe and they largely rule out single star evolutionary models in favor of a binary channel as the origin of this SN. We also constrain the activity of the progenitor to be small on an absolute scale, with the RMS $UBVR$ optical variability $<2500L_\\odot$ and long-term dimming or brightening trends $<1000L_\\odot/\\text{year}$ in all four bands.

  17. Gamma ray bursts, supernovae and metallicity in the intergalactic medium

    CERN Document Server

    Dado, S; De Rújula, Alvaro; Dado, Shlomo; Dar, Arnon

    2007-01-01

    The mean iron abundance observed in the intracluster medium of galaxy clusters is consistent with the mean amount of iron injected in the universe per unit volume by standard supernova (SN) explosions with a rate proportional to the cosmic star-formation rate. But very little is known about field SNe at high red-shifts. Such SNe could have occurred primarily in highly obscured environments, avoiding detection. Supporting evidence for field SNe is provided by SNe associated with gamma ray bursts (GRBs) without a host galaxy and by the ratio of well localized GRBs with and without a host galaxy. A direct test of the field-SN origin of iron in the intergalactic medium would require the measurement of their rate per comoving unit volume as function of red-shift. This is feasible with IR telescopes, such as the Spitzer Space Telescope.

  18. The Rise and Peak of the Luminous Type IIn SN 2017hcc/ATLAS17lsn from ASAS-SN and Swift UVOT Data

    Science.gov (United States)

    Prieto, J. L.; Chen, Ping; Dong, Subo; Shappee, B. J.; Seibert, M.; Bersier, D.; Holoien, T. W.-S.; Kochanek, C. S.; Stanek, K. Z.; Thompson, T. A.

    2017-12-01

    We present observations of the rise and peak of the Type IIn supernova SN 2017hcc/ATLAS17lsn obtained by the All-Sky Automated Survey for Supernovae (ASAS-SN) and Swift UVOT. The light curve of SN 2017hcc/ATLAS17lsn peaks at $V\\simeq 13.7$ mag, which from the estimated redshift of the host galaxy ($z=0.0168$, $D\\simeq 73$ Mpc) implies an absolute peak magnitude $M_{V,peak} \\simeq -20.7$ mag. The near-UV to optical spectral energy distribution of SN 2017hcc/ATLAS17lsn from Swift UVOT is consistent with a hot, but cooling blackbody with $\\rm T_{bb}\\simeq 16500$ K on Oct. 28.4 and $\\rm T_{bb} \\simeq 11700$ K on Nov. 19.6. The estimated peak bolometric luminosity $L_{bol, peak}\\simeq 1.3\\times 10^{44}$ erg s$^{-1}$ makes SN2017hcc/ATLAS17lsn one of the most luminous Type IIn supernovae studied to date. From the bolometric light curve we constrain the risetime to be $\\sim 27$ days and the total radiated energy of the event to date is $4\\times 10^{50}$ erg.

  19. Automated Supernova Discovery (Abstract)

    Science.gov (United States)

    Post, R. S.

    2015-12-01

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

  20. Modelling the interaction of thermonuclear supernova remnants with circumstellar structures: the case of Tycho's supernova remnant

    Science.gov (United States)

    Chiotellis, A.; Kosenko, D.; Schure, K. M.; Vink, J.; Kaastra, J. S.

    2013-10-01

    The well-established Type Ia remnant of Tycho's supernova (SN 1572) reveals discrepant ambient medium-density estimates based on either the measured dynamics or the X-ray emission properties. This discrepancy can potentially be solved by assuming that the supernova remnant (SNR) shock initially moved through a stellar wind bubble, but is currently evolving in the uniform interstellar medium with a relatively low density. We investigate this scenario by combining hydrodynamical simulations of the wind-loss phase and the SNR evolution with a coupled X-ray emission model, which includes non-equilibrium ionization. For the explosion models we use the well-known W7 deflagration model and the delayed detonation model that was previously shown to provide good fits to the X-ray emission of Tycho's SNR. Our simulations confirm that a uniform ambient density cannot simultaneously reproduce the dynamical and X-ray emission properties of Tycho. In contrast, models that considered that the remnant was evolving in a dense, but small, wind bubble reproduce reasonably well both the measured X-ray emission spectrum and the expansion parameter of Tycho's SNR. Finally, we discuss possible mass-loss scenarios in the context of single- and double-degenerate models which possibly could form such a small dense wind bubble.

  1. Zooming in on Supernova 1987A at submillimetre wavelengths

    Science.gov (United States)

    Lakićević, M.; van Loon, J. Th.; Stanke, T.; De Breuck, C.; Patat, F.

    2012-05-01

    Context. Supernova 1987A (SN 1987A) in the neighbouring Large Magellanic Cloud offers a superb opportunity to follow the evolution of a supernova and its remnant in unprecedented detail. Recently, far-infrared (far-IR) and sub-mm emission was detected from the direction of SN 1987A, which was interpreted as due to the emission from dust, possibly freshly synthesized in the SN ejecta. Aims: To better constrain the location and hence origin of the far-IR and sub-mm emission in SN 1987A, we have attempted to resolve the object in that part of the electro-magnetic spectrum. Methods: We observed SN 1987A during July-September 2011 with the Atacama Pathfinder EXperiment (APEX), at a wavelength of 350 μm with the Submillimetre APEX BOlometer CAmera (SABOCA) and at 870 μm with the Large APEX BOlometer CAmera (LABOCA). The 350-μm image has superior angular resolution (8'') over that of the Herschel Space Observatory 350-μm image (25''). The 870-μm observation (at 20'' resolution) is a repetition of a similar observation made in 2007. Results: In both images, at 350 and 870 μm, emission is detected from SN 1987A, and the source is unresolved. The flux densities in the new (2011) measurements are consistent with those measured before with Herschel at 350 μm (in 2010) and with APEX at 870 μm (in 2007). A higher dust temperature (≈33 K) and lower dust mass might be possible than what was previously thought. Conclusions: The new measurements, at the highest angular resolution achieved so far at far-IR and sub-mm wavelengths, strengthen the constraints on the location of the emission, which is thought to be close to the site of SN 1987A and its circumstellar ring structures. These measurements set the stage for upcoming observations at even higher angular resolution with the Atacama Large Millimeter Array (ALMA). Processed data is only available via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/541/L1

  2. A Measurement of the Rate of Type Ia Supernovae in Galaxy Clusters from the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Dilday, Benjamin; /Rutgers U., Piscataway /Chicago U. /KICP, Chicago; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Becker, Andrew; /Washington U., Seattle, Astron. Dept.; Bender, Ralf; /Munich, Tech. U. /Munich U. Observ.; Castander, Francisco; /Barcelona, IEEC; Cinabro, David; /Wayne State U.; Frieman, Joshua A.; /Chicago U. /Fermilab; Galbany, Lluis; /Barcelona, IFAE; Garnavich, Peter; /Notre Dame U.; Goobar, Ariel; /Stockholm U., OKC /Stockholm U.; Hopp, Ulrich; /Munich, Tech. U. /Munich U. Observ. /Tokyo U.

    2010-03-01

    We present measurements of the Type Ia supernova (SN) rate in galaxy clusters based on data from the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. The cluster SN Ia rate is determined from 9 SN events in a set of 71 C4 clusters at z {le} 0.17 and 27 SN events in 492 maxBCG clusters at 0.1 {le} z {le} 0.3. We find values for the cluster SN Ia rate of (0.37{sub -0.12-0.01}{sup +0.17+0.01}) SNur h{sup 2} and (0.55{sub -0.11-0.01}{sup +0.13+0.02}) SNur h{sup 2} (SNux = 10{sup -12}L{sub x{circle_dot}}{sup -1} yr{sup -1}) in C4 and maxBCG clusters, respectively, where the quoted errors are statistical and systematic, respectively. The SN rate for early-type galaxies is found to be (0.31{sub -0.12-0.01}{sup +0.18+0.01}) SNur h{sup 2} and (0.49{sub -0.11-0.01}{sup +0.15+0.02}) SNur h{sup 2} in C4 and maxBCG clusters, respectively. The SN rate for the brightest cluster galaxies (BCG) is found to be (2.04{sub -1.11-0.04}{sup +1.99+0.07}) SNur h{sup 2} and (0.36{sub -0.30-0.01}{sup +0.84+0.01}) SNur h{sup 2} in C4 and maxBCG clusters, respectively. The ratio of the SN Ia rate in cluster early-type galaxies to that of the SN Ia rate in field early-type galaxies is 1.94{sub -0.91-0.015}{sup +1.31+0.043} and 3.02{sub -1.03-0.048}{sup +1.31+0.062}, for C4 and maxBCG clusters, respectively. The SN rate in galaxy clusters as a function of redshift, which probes the late time SN Ia delay distribution, shows only weak dependence on redshift. Combining our current measurements with previous measurements, we fit the cluster SN Ia rate data to a linear function of redshift, and find r{sub L} = [(0.49{sub -0.14}{sup +0.15}) + (0.91{sub -0.81}{sup +0.85}) x z] SNuB h{sup 2}. A comparison of the radial distribution of SNe in cluster to field early-type galaxies shows possible evidence for an enhancement of the SN rate in the cores of cluster early-type galaxies. With an observation of at most 3 hostless, intra-cluster SNe Ia, we estimate the fraction of cluster SNe that are

  3. X-Ray Illumination of the Ejecta of Supernova 1987A

    Science.gov (United States)

    Larsson, J.; Fransson, C.; Oestlin, G.; Groeningsson, P.; Jerkstrand, A.; Kozma, C.; Sollerman, J.; Challis, P.; Kirshner, R. P.; Chevalier, R. A.; hide

    2011-01-01

    When a massive star explodes as a supernova, substantial amounts of radioactive elements-primarily Ni-56, Ni-57 and Ti-44 are produced. After the initial from shock heating, the light emitted by the supernova is due to the decay of these elements. However, after decades, the energy powering a supernova remnant comes from the shock interaction between the ejecta and the surrounding medium. The transition to this phase has hitherto not been observed: supernovae occur too infrequently in the Milky Way to provide a young example, and extragalactic supernovae are generally too faint and too small. Here we report observations that show this transition in the supernova SN 1987A in the Large Magellan Cloud. From 1994 to 200l, the ejecta faded owing to radioactive decay of Ti-44 as predicted. Then the flux started to increase, more than doubling by the end of 2009. We show that this increase is the result of heat deposited by X-rays produced as the ejecta interacts with the surrounding material. In time, the X-rays will penetrate farther into the ejects, enabling us to analyse the structure and chemistry of the vanished star.

  4. Going gently into the night: constraining Type Ia supernova nucleosynthesis using late-time photometry

    Science.gov (United States)

    Graur, Or

    2016-10-01

    We propose to use WFC3 photometry to construct the optical light curves of the nearby Type Ia supernovae SN 2015F and ASASSN-14lp at late times (>500 days after maximum light). These light curves will allow us to conduct a fundamental test of the theoretically predicted behavior of Type Ia supernova light curves at late times. We will observationally determine whether the nuclear physics of Type Ia supernova ejecta are solely determined by the radioactive decay of 56Co to 56Fe, or whether (and by how much) other nuclear heating mechanisms (such as the leptonic decays of 57Co) become discernible, as predicted. The spatial resolution of HST+WFC3 is crucial to the success of this experiment. At these late times, the fading supernovae are as bright as other surrounding objects (bright stars, star clusters), which would dominate the point-spread functions of ground-based observatories. Due to the rarity of nearby Type Ia supernovae, this experiment will double the sample of supernovae for which this experiment has been conducted and cut the uncertainty on the results by half. Moreover, if this experiment is not conducted in Cycle 24, it is highly unlikely that we would be able to perform it again during the remaining lifetime of HST.

  5. A MISSING-LINK IN THE SUPERNOVA–GRB CONNECTION: THE CASE OF SN 2012ap

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborti, Sayan; Soderberg, Alicia; Kamble, Atish; Margutti, Raffaella; Milisavljevic, Dan; Dittmann, Jason [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Chomiuk, Laura [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Yadav, Naveen; Ray, Alak [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400005 (India); Hurley, Kevin [Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720 (United States); Bietenholz, Michael [Department of Physics and Astronomy, York University, 4700 Keele St., M3J 1P3 Ontario (Canada); Brunthaler, Andreas [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany); Pignata, Giuliano [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Pian, Elena [Scuola Normale Superiore, Piazza Dei Cavalieri 7—I-56126 Pisa (Italy); Mazzali, Paolo [Liverpool John Moores University, IC2, 146 Brownlow Hill, Liverpool (United Kingdom); Fransson, Claes [Department of Astronomy, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden); Bartel, Norbert [Hartebeesthoek Radio Astronomy Observatory, PO Box 443, Krugersdrop, 1740 (South Africa); Hamuy, Mario [Departamento de Astronoma, Universidad de Chile (Chile); Levesque, Emily [University of Colorado, C327A, Boulder, CO 80309 (United States); MacFadyen, Andrew, E-mail: schakraborti@fas.harvard.edu [New York University, 4 Washington Place, New York, NY 10003 (United States); and others

    2015-06-01

    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 a 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. However, 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. We discovered a bright and rapidly evolving radio counterpart driven by the circumstellar interaction of the relativistic ejecta. However, we did not find any coincident GRB with an isotropic fluence of more than one-sixth of the fluence from GRB 980425. This shows for the first time that central engines in SNe Ic, even without an observed GRB, can produce both relativistic and rapidly decelerating outflows like GRBs.

  6. Time-resolved Polarimetry of the Superluminous SN 2015bn with the Nordic Optical Telescope

    DEFF Research Database (Denmark)

    Leloudas, Giorgos; Maund, Justyn R.; Gal-Yam, Avishay

    2017-01-01

    We present imaging polarimetry of the superluminous supernova SN 2015bn, obtained over nine epochs between -20 and +46 days with the Nordic Optical Telescope. This was a nearby, slowly evolving Type I superluminous supernova that has been studied extensively and for which two epochs of spectropol......We present imaging polarimetry of the superluminous supernova SN 2015bn, obtained over nine epochs between -20 and +46 days with the Nordic Optical Telescope. This was a nearby, slowly evolving Type I superluminous supernova that has been studied extensively and for which two epochs...... of spectropolarimetry are also available. Based on field stars, we determine the interstellar polarization in the Galaxy to be negligible. The polarization of SN 2015bn shows a statistically significant increase during the last epochs, confirming previous findings. Our well-sampled imaging polarimetry series allows us......, to a more aspherical inner core, dominated by freshly nucleosynthesized material. This two-layered model might account for the characteristic appearance and properties of Type I superluminous supernovae....

  7. Things begin to happen around Supernova 1987A

    Science.gov (United States)

    1994-01-01

    On 23 February 1994, it will be exactly seven years since the explosion of Supernova 1987A in the Large Magellanic Cloud [1] was first observed, at a distance of approx. 160,000 light-years. It was the first naked-eye supernova to be seen in almost four hundred years. Few events in modern astronomy have met with such an enthusiastic response by the scientists and this famous object has been under constant surveillance ever since. After several years of relative quiescence, things are now beginning to happen in the immediate neighbourhood of SN 1987A. Recent observations with the ESO 3.5 m New Technology Telescope (NTT) indicate that interaction between the stellar material which was ejected during the explosion and the surrounding ring-shaped nebulae has started. This signals the beginning of a more active phase during which the supernova is likely to display a number of new and interesting phenomena, never before observed. SEVEN YEARS IN THE LIFE OF A SUPERNOVA After brightening to maximum light at about magnitude 3 a few months after the explosion, the long period of steady fading which is typical for supernovae, set in by mid-1987. The matter ejected by the explosion took the form of an expanding fireball, which began to spread through the nearly empty space around the supernova with a velocity of almost 10,000 km/sec. As it cooled, the temperature and therefore the total brightness decreased and the supernova became fainter and fainter. At the present moment, the magnitude of SN 1987A is about 18.5, that is almost 2 million times fainter than it was at maximum. Various phenomena have been observed around SN 1987A during the past years. Already in early 1988, light echoes were seen as concentric, slowly expanding luminous circles; they represent the reflections of the explosion light flash in interstellar clouds inside the Large Magellanic Cloud, between the supernova and us. In 1989, high-resolution observations with the NTT showed an elliptical ``ring

  8. Polymorphism in Energetic Materials

    Science.gov (United States)

    2008-01-01

    the classic cases of polymorphism at ambient conditions in the energetic field are TNT, HMX , and CL20 (Fig. 1). TNT [2,4,6-trinitrotoluene] is known...2008 NRL REVIEW 71 Polymorphism in Energetic Materials J.R. Deschamps,1 D.A. Parrish,1 and R.J. Butcher2 1Laboratory for Structure of Matter...2Department of Chemistry, Howard University Polymorphism often occurs in energetic materials. Differences in the forms range from conformational changes in

  9. e-MERLIN 5GHz observations of SN2017eaw in NGC6946

    Science.gov (United States)

    Argo, Megan; Torres, Miguel Perez; Beswick, Rob; Wrigley, Nick

    2017-05-01

    We observed the position of SN2017eaw in NGC6946 (ATel #10372) with e-MERLIN at a central frequency of 5.1 GHz on May 19/20 2017. The supernova was observed over 18 hours, with 10 hours spent on-target.

  10. Spectroscopic classification of Gaia, ASAS-SN and TOCP transients with the WHT+ISIS

    Science.gov (United States)

    Campbell, H.; Wevers, T.; Fraser, M.; Jonker, P. G.; Wyrzykowski, L.; Hodgkin, S.; Blagorodnova, N.

    2015-06-01

    We report spectroscopic confirmation and classifications for reported Gaia Photometric Science Alerts (http://gaia.ac.uk/selected-gaia-science-alerts), together with targets from the All-Sky Automated Survey for Supernovae (ASAS-SN; Shappee et al. 2014) and the TOCP list.

  11. Radioactive Iron Rain: Transporting $^{60}$Fe in Supernova Dust to the Ocean Floor

    CERN Document Server

    Fry, Brian J.; Ellis, John R.

    2016-01-01

    Several searches have found evidence of $^{60}$Fe deposition, presumably from a near-Earth supernova (SN), with concentrations that vary in different locations on Earth. This paper examines various influences on the path of interstellar dust carrying $^{60}$Fe from a SN through the heliosphere, with the aim of estimating the final global distribution on the ocean floor. We study the influences of magnetic fields, angle of arrival, wind and ocean cycling of SN material on the concentrations at different locations. We find that the passage of SN material through the mesosphere/lower thermosphere (MLT) is the greatest influence on the final global distribution, with ocean cycling causing lesser alteration as the SN material sinks to the ocean floor. SN distance estimates in previous works that assumed a uniform distribution are a good approximation. Including the effects on surface distributions, we estimate a distance of $46^{+10}_{-6}$ pc for a $8-10 \\ M_{\\odot}$ SN progenitor. This is consistent with a SN occ...

  12. Deep Limits on the X-ray and Radio Emission From the Nearby Type Iax SN2014dt

    Science.gov (United States)

    Stauffer, Candice; Margutti, Raffaella; Coppejans, Deannne

    2018-01-01

    Type Iax Supernovae (SN Iax) have been recently recognized as a new class of stellar explosions in 2012. SN Iax constitute the largest class of ``peculiar thermonuclear explosions'' from white dwarf (WD) stellar progenitors in binary systems. They are characterized by lower ejecta velocity, lower luminsity and non-standard late-time spectral evolution, when compared to the more common Type Ia SNe. Here I present deep radio and X-ray observations of the closest type Iax SN yet discovered, SN2014dt. The SN shock interaction with the medium is a very well known source of radio and X-ray emission. My observations of SN2014dt uniquely constrain the density in the SN sub-pc environment (which cannot be investigated otherwise), and allow me to put constraints on the mysterious nature of the stellar companion.

  13. Measuring Cosmological Parameters with Photometrically Classified Pan-STARRS Supernovae

    Science.gov (United States)

    Jones, David; Scolnic, Daniel; Riess, Adam; Rest, Armin; Kirshner, Robert; Berger, Edo; Kessler, Rick; Pan, Yen-Chen; Foley, Ryan; Chornock, Ryan; Ortega, Carolyn; Challis, Peter; Burgett, William; Chambers, Kenneth; Draper, Peter; Flewelling, Heather; Huber, Mark; Kaiser, Nick; Kudritzki, Rolf; Metcalfe, Nigel; Tonry, John; Wainscoat, Richard J.; Waters, Chris; Gall, E. E. E.; Kotak, Rubina; McCrum, Matt; Smartt, Stephen; Smith, Ken

    2018-01-01

    We use nearly 1,200 supernovae (SNe) from Pan-STARRS and ~200 low-z (z satellite, we measure the dark energy equation of state parameter w to be -0.986±0.058 (stat+sys). If we allow w to evolve with redshift as w(a) = w0 + wa(1-a), we find w0 = -0.923±0.148 and wa = -0.404±0.797. These results are consistent with measurements of cosmological parameters from the JLA and from a new analysis of 1049 spectroscopically confirmed SNe Ia (Scolnic et al. 2017). We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling the CC SN contamination, finding that none of these variants gives a w that differs by more than 1% from the baseline measurement. The systematic uncertainty on w due to marginalizing over the CC SN contamination, σwCC = 0.019, is approximately equal to the photometric calibration uncertainty and is lower than the systematic uncertainty in the SN\\,Ia dispersion model (σwdisp = 0.024). Our data provide one of the best current constraints on w, demonstrating that samples with ~5% CC SN contamination can give competitive cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.

  14. Deja Vu All Over Again: The Reappearance of Supernova Refsdal

    Science.gov (United States)

    Kelly, P. L.; Rodney, S. A.; Treu, T.; Strolger, L.-G.; Foley, R. J.; Jha, S. W.; Selsing, J.; Brammer, G.; Bradač, M.; Cenko, S. B.; Graur, O.; Filippenko, A. V.; Hjorth, J.; McCully, C.; Molino, A.; Nonino, M.; Riess, A. G.; Schmidt, K. B.; Tucker, B.; von der Linden, A.; Weiner, B. J.; Zitrin, A.

    2016-03-01

    In Hubble Space Telescope (HST) imaging taken on 2014 November 10, four images of supernova (SN) “Refsdal” (redshift z = 1.49) appeared in an Einstein-cross-like configuration (images S1-S4) around an early-type galaxy in the cluster MACS J1149.5+2223 (z = 0.54). Almost all lens models of the cluster have predicted that the SN should reappear within a year in a second host-galaxy image created by the cluster’s potential. In HST observations taken on 2015 December 11, we find a new source at the predicted position of the new image of SN Refsdal approximately 8\\prime\\prime from the previous images S1-S4. This marks the first time the appearance of a SN at a particular time and location in the sky was successfully predicted in advance! We use these data and the light curve from the first four observed images of SN Refsdal to place constraints on the relative time delay and magnification of the new image (SX) compared to images S1-S4. This enables us, for the first time, to test “blind” lens model predictions of both magnifications and time delays for a lensed SN. We find that the timing and brightness of the new image are consistent with the blind predictions of a fraction of the models. The reappearance illustrates the discriminatory power of this blind test and its utility to uncover sources of systematic uncertainty. From planned HST photometry, we expect to reach a precision of 1%-2% on the time delay between S1-S4 and SX.

  15. A Massive Shell of Supernova-formed Dust in SNR G54.1+0.3

    Energy Technology Data Exchange (ETDEWEB)

    Temim, Tea [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Dwek, Eli; Arendt, Richard G. [Observational Cosmology Lab, Code 665, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Borkowski, Kazimierz J.; Reynolds, Stephen P. [North Carolina State University, Raleigh, NC 27695 (United States); Slane, Patrick; Raymond, John C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Gelfand, Joseph D. [New York University, Abu Dhabi (United Arab Emirates)

    2017-02-10

    While theoretical models of dust condensation predict that most refractory elements produced in core-collapse supernovae (SNe) efficiently condense into dust, a large quantity of dust has so far only been observed in SN 1987A. We present an analysis of observations from the Spitzer Space Telescope , Herschel Space Observatory , Stratospheric Observatory for Infrared Astronomy, and AKARI of the infrared shell surrounding the pulsar wind nebula in the supernova remnant G54.1+0.3. We attribute a distinctive spectral feature at 21 μ m to a magnesium silicate grain species that has been invoked in modeling the ejecta-condensed dust in Cas A, which exhibits the same spectral signature. If this species is responsible for producing the observed spectral feature and accounts for a significant fraction of the observed infrared continuum, we find that it would be the dominant constituent of the dust in G54.1+0.3, with possible secondary contributions from other compositions, such as carbon, silicate, or alumina grains. The total mass of SN-formed dust required by this model is at least 0.3 M {sub ⊙}. We discuss how these results may be affected by varying dust grain properties and self-consistent grain heating models. The spatial distribution of the dust mass and temperature in G54.1+0.3 confirms the scenario in which the SN-formed dust has not yet been processed by the SN reverse shock and is being heated by stars belonging to a cluster in which the SN progenitor exploded. The dust mass and composition suggest a progenitor mass of 16–27 M {sub ⊙} and imply a high dust condensation efficiency, similar to that found for Cas A and SN 1987A. The study provides another example of significant dust formation in a Type IIP SN explosion and sheds light on the properties of pristine SN-condensed dust.

  16. Neutrinos and nucleosynthesis in supernova

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-05-15

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

  17. Intensive Monitoring Survey of Nearby Galaxies (IMSNG): Catching Early Light Curves of Supernovae

    Science.gov (United States)

    Im, Myungshin; IMSNG Team

    2018-01-01

    SNe light curves have been used to study the expansion history of the universe, and a lot of efforts have gone into understanding the overall shape of the radioactively powered light curve. However, we still have little direct observational evidence for the theorized SN progenitor systems. Recent studies suggest that the light curve of a supernova shortly after its explosion (world. Through this survey, we expect to catch the very early precursor emission as faint as R=21 mag (~0.1 Rsun for the progenitor). This poster outlines this project, and present a few scientific highlights, such as the early light curve of SN 2015F in NGC 2442.

  18. IMPROVING COSMOLOGICAL DISTANCE MEASUREMENTS USING TWIN TYPE IA SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Fakhouri, H. K.; Boone, K.; Aldering, G.; Aragon, C.; Bailey, S.; Fagrelius, P. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Fleury, M. [Laboratoire de Physique Nucléaire et des Hautes Énergies, Université Pierre et Marie Curie Paris 6, Université Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Barbary, K. [Department of Physics, University of California Berkeley, 366 LeConte Hall MC 7300, Berkeley, CA 94720-7300 (United States); Baugh, D.; Chen, J. [Tsinghua Center for Astrophysics, Tsinghua University, Beijing 100084 (China); Buton, C.; Chotard, N.; Copin, Y. [Université de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, F-69622, Lyon (France); Childress, M. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Feindt, U. [Institut fur Physik, Humboldt-Universitat zu Berlin, Newtonstrasse 15, D-12489 Berlin (Germany); Fouchez, D. [Centre de Physique des Particules de Marseille, Aix-Marseille Université, CNRS/IN2P3, 163 avenue de Luminy—Case 902—F-13288 Marseille Cedex 09 (France); Gangler, E. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); Collaboration: Nearby Supernova Factory; and others

    2015-12-10

    We introduce a method for identifying “twin” Type Ia supernovae (SNe Ia) and using them to improve distance measurements. This novel approach to SN Ia standardization is made possible by spectrophotometric time series observations from the Nearby Supernova Factory (SNfactory). We begin with a well-measured set of SNe, find pairs whose spectra match well across the entire optical window, and then test whether this leads to a smaller dispersion in their absolute brightnesses. This analysis is completed in a blinded fashion, ensuring that decisions made in implementing the method do not inadvertently bias the result. We find that pairs of SNe with more closely matched spectra indeed have reduced brightness dispersion. We are able to standardize this initial set of SNfactory SNe to 0.083 ± 0.012 mag, implying a dispersion of 0.072 ± 0.010 mag in the absence of peculiar velocities. We estimate that with larger numbers of comparison SNe, e.g., using the final SNfactory spectrophotometric data set as a reference, this method will be capable of standardizing high-redshift SNe to within 0.06–0.07 mag. These results imply that at least 3/4 of the variance in Hubble residuals in current SN cosmology analyses is due to previously unaccounted-for astrophysical differences among the SNe.

  19. Host Galaxy Spectra and Consequences for SN Typing from the SDSS SN Survey

    Energy Technology Data Exchange (ETDEWEB)

    Olmstead, Matthew D.; Brown, Peter J.; Sako, Masao; Bassett, Bruce; Bizyaev, Dmitry; Brinkmann, J.; Brownstein, Joel R.; Brewington, Howard; Campbell, Heather; D’Andrea, Chris B.; Dawson, Kyle S.; Ebelke, Garrett L.; Frieman, Joshua A.; Galbany, Lluís; Garnavich, Peter; Gupta, Ravi R.; Hlozek, Renee; Jha, Saurabh W.; Kunz, Martin; Lampeitl, Hubert; Malanushenko, Elena; Malanushenko, Viktor; Marriner, John; Miquel, Ramon; Montero-Dorta, Antonio D.; Nichol, Robert C.; Oravetz, Daniel J.; Pan, Kaike; Schneider, Donald P.; Simmons, Audrey E.; Smith, Mathew; Snedden, Stephanie A.

    2014-03-06

    We present the spectroscopy from 5254 galaxies that hosted supernovae (SNe) or other transient events in the Sloan Digital Sky Survey II (SDSS-II). Obtained during SDSS-I, SDSS-II, and the Baryon Oscillation Spectroscopic Survey (BOSS), this sample represents the largest systematic, unbiased, magnitude limited spectroscopic survey of supernova (SN) host galaxies. Using the host galaxy redshifts, we test the impact of photometric SN classification based on SDSS imaging data with and without using spectroscopic redshifts of the host galaxies. Following our suggested scheme, there are a total of 1166 photometrically classified SNe Ia when using a flat redshift prior and 1126 SNe Ia when the host spectroscopic redshift is assumed. For 1024 (87.8%) candidates classified as likely SNe Ia without redshift information, we find that the classification is unchanged when adding the host galaxy redshift. Using photometry from SDSS imaging data and the host galaxy spectra, we also report host galaxy properties for use in future nalysis of SN astrophysics. Finally, we investigate the differences in the interpretation of the light curve properties with and without knowledge of the redshift. When using the SALT2 light curve fitter, we find a 21% increase in the number of fits that converge when using the spectroscopic redshift. Without host galaxy redshifts, we find that SALT2 light curve fits are systematically biased towards lower photometric redshift estimates and redder colors in the limit of low signal-to-noise data. The general improvements in performance of the light curve fitter and the increased diversity of the host galaxy sample highlights the importance of host galaxy spectroscopy for current photometric SN surveys such as the Dark Energy Survey and future surveys such as the Large Synoptic Survey Telescope.

  20. Astronomy. ASASSN-15lh: A highly super-luminous supernova.

    Science.gov (United States)

    Dong, Subo; Shappee, B J; Prieto, J L; Jha, S W; Stanek, K Z; Holoien, T W-S; Kochanek, C S; Thompson, T A; Morrell, N; Thompson, I B; Basu, U; Beacom, J F; Bersier, D; Brimacombe, J; Brown, J S; Bufano, F; Chen, Ping; Conseil, E; Danilet, A B; Falco, E; Grupe, D; Kiyota, S; Masi, G; Nicholls, B; Olivares E, F; Pignata, G; Pojmanski, G; Simonian, G V; Szczygiel, D M; Woźniak, P R

    2016-01-15

    We report the discovery of ASASSN-15lh (SN 2015L), which we interpret as the most luminous supernova yet found. At redshift z = 0.2326, ASASSN-15lh reached an absolute magnitude of Mu ,AB = -23.5 ± 0.1 and bolometric luminosity Lbol = (2.2 ± 0.2) × 10(45) ergs s(-1), which is more than twice as luminous as any previously known supernova. It has several major features characteristic of the hydrogen-poor super-luminous supernovae (SLSNe-I), whose energy sources and progenitors are currently poorly understood. In contrast to most previously known SLSNe-I that reside in star-forming dwarf galaxies, ASASSN-15lh appears to be hosted by a luminous galaxy (MK ≈ -25.5) with little star formation. In the 4 months since first detection, ASASSN-15lh radiated (1.1 ± 0.2) × 10(52) ergs, challenging the magnetar model for its engine. Copyright © 2016, American Association for the Advancement of Science.

  1. A HIGH-RESOLUTION SPECTROSCOPIC SEARCH FOR THE REMAINING DONOR FOR TYCHO'S SUPERNOVA

    Energy Technology Data Exchange (ETDEWEB)

    Kerzendorf, Wolfgang E.; Yong, David; Schmidt, Brian P.; Murphy, Simon J.; Bessell, Michael S. [Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611 (Australia); Simon, Joshua D. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Jeffery, C. Simon [Armagh Observatory, College Hill, Armagh BT61 9DG (United Kingdom); Anderson, Jay [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Podsiadlowski, Philipp [Department of Astrophysics, University of Oxford, Oxford, OX1 3RH (United Kingdom); Gal-Yam, Avishay [Benoziyo Center for Astrophysics, Faculty of Physics, Weizmann Institute of Science, Rehovot 76100 (Israel); Silverman, Jeffrey M.; Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Nomoto, Ken' ichi [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Venn, Kim A. [Department of Physics and Astronomy, University of Victoria, Elliott Building, 3800 Finnerty Road, Victoria, BC V8P 5C2 (Canada); Foley, Ryan J., E-mail: wkerzend@mso.anu.edu.au [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2013-09-10

    In this paper, we report on our analysis using Hubble Space Telescope astrometry and Keck-I HIRES spectroscopy of the central six stars of Tycho's supernova remnant (SN 1572). With these data, we measured the proper motions, radial velocities, rotational velocities, and chemical abundances of these objects. Regarding the chemical abundances, we do not confirm the unusually high [Ni/Fe] ratio previously reported for Tycho-G. Rather, we find that for all metrics in all stars, none exhibit the characteristics expected from traditional Type Ia supernova single-degenerate-scenario calculations. The only possible exception is Tycho-B, a rare, metal-poor A-type star; however, we are unable to find a suitable scenario for it. Thus, we suggest that SN 1572 cannot be explained by the standard single-degenerate model.

  2. Reconstructing the Scene: New Views of Supernovae and Progenitors from the SNSPOL Project

    Science.gov (United States)

    Hoffman, Jennifer L.; Williams, G. Grant; Leonard, Douglas C.; Bilinski, Christopher; Dessart, Luc; Huk, Leah N.; Mauerhan, Jon C.; Milne, Peter; Porter, Amber L.; Smith, Nathan; Smith, Paul S.

    2017-11-01

    Because polarization encodes geometrical information about unresolved scattering regions, it provides a unique tool for analyzing the 3-D structures of supernovae (SNe) and their surroundings. SNe of all types exhibit time-dependent spectropolarimetric signatures produced primarily by electron scattering. These signatures reveal physical phenomena such as complex velocity structures, changing illumination patterns, and asymmetric morphologies within the ejecta and surrounding material. Interpreting changes in polarization over time yields unprecedentedly detailed information about supernovae, their progenitors, and their evolution. Begun in 2012, the SNSPOL Project continues to amass the largest database of time-dependent spectropolarimetric data on SNe. I present an overview of the project and its recent results. In the future, combining such data with interpretive radiative transfer models will further constrain explosion mechanisms and processes that shape SN ejecta, uncover new relationships among SN types, and probe the properties of progenitor winds and circumstellar material.

  3. Supernovae Rates: A Cosmic History

    OpenAIRE

    Yungelson, L. R.; Livio, M.

    1999-01-01

    We discuss the cosmic history of supernovae on the basis of various assumptions and recent data on the star formation history. We show that supernova rates as a function of redshift can be used to place significant constraints on progenitor models, on the star formation history, and on the importance of dust obscuration. We demonstrate that it is unlikely that the current observational indications for the existence of a cosmological constant are merely an artifact of the dominance of differen...

  4. RX-J0852−4622: THE NEAREST HISTORICAL SUPERNOVA REMNANT – AGAIN

    Directory of Open Access Journals (Sweden)

    Bernd Aschenbach

    2013-12-01

    Full Text Available RX-J0852−4622, a supernova remnant, is demonstrated to be closer than 500 pc, based on the measurements of the angular radius, the angular expansion rate and the TeV g-ray flux. This is a new method of limiting the distance to any supernova remnant with hadronic induced TeV g-ray flux. The progenitor star of RX-J0852−4622 probably exploded in its blue supergiant wind, like SN 1987A, preceeded by a red supergiant phase. A cool dense shell, expected around the outskirts of the red wind, my have been identified. The distance (200 pc and age (680 yr of the supernova remnant, originally proposed, are supported.

  5. iPTF16geu: A multiply imaged, gravitationally lensed type Ia supernova

    Science.gov (United States)

    Goobar, A.; Amanullah, R.; Kulkarni, S. R.; Nugent, P. E.; Johansson, J.; Steidel, C.; Law, D.; Mörtsell, E.; Quimby, R.; Blagorodnova, N.; Brandeker, A.; Cao, Y.; Cooray, A.; Ferretti, R.; Fremling, C.; Hangard, L.; Kasliwal, M.; Kupfer, T.; Lunnan, R.; Masci, F.; Miller, A. A.; Nayyeri, H.; Neill, J. D.; Ofek, E. O.; Papadogiannakis, S.; Petrushevska, T.; Ravi, V.; Sollerman, J.; Sullivan, M.; Taddia, F.; Walters, R.; Wilson, D.; Yan, L.; Yaron, O.

    2017-04-01

    We report the discovery of a multiply imaged, gravitationally lensed type Ia supernova, iPTF16geu (SN 2016geu), at redshift z = 0.409. This phenomenon was identified because the light from the stellar explosion was magnified more than 50 times by the curvature of space around matter in an intervening galaxy. We used high-spatial-resolution observations to resolve four images of the lensed supernova, approximately 0.3 arc seconds from the center of the foreground galaxy. The observations probe a physical scale of ~1 kiloparsec, smaller than is typical in other studies of extragalactic gravitational lensing. The large magnification and symmetric image configuration imply close alignment between the lines of sight to the supernova and to the lens. The relative magnifications of the four images provide evidence for substructures in the lensing galaxy.

  6. An unusual white dwarf star may be a surviving remnant of a subluminous Type Ia supernova

    Science.gov (United States)

    Vennes, S.; Nemeth, P.; Kawka, A.; Thorstensen, J. R.; Khalack, V.; Ferrario, L.; Alper, E. H.

    2017-08-01

    Subluminous Type Ia supernovae, such as the Type Iax-class prototype SN 2002cx, are described by a variety of models such as the failed detonation and partial deflagration of an accreting carbon-oxygen white dwarf star or the explosion of an accreting, hybrid carbon-oxygen-neon core. These models predict that bound remnants survive such events with, according to some simulations, a high kick velocity. We report the discovery of a high proper motion, low-mass white dwarf (LP 40-365) that travels at a velocity greater than the Galactic escape velocity and whose peculiar atmosphere is dominated by intermediate-mass elements. Strong evidence indicates that this partially burnt remnant was ejected following a subluminous Type Ia supernova event. This supports the viability of single-degenerate supernova progenitors.

  7. PRECISION MEASUREMENT OF THE MOST DISTANT SPECTROSCOPICALLY CONFIRMED SUPERNOVA Ia WITH THE HUBBLE SPACE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, D.; Rykoff, E.; Aldering, G.; Barbary, K.; Fakhouri, H. K.; Goldhaber, G.; Hsiao, E. Y. [E. O. Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Knop, R. A. [Quest University Canada, Squamish, BC (Canada); Amanullah, R.; Goobar, A. [The Oskar Klein Centre, Department of Physics, AlbaNova, Stockholm University, SE-106 91 Stockholm (Sweden); Burns, M. S. [Colorado College, 14 East Cache La Poudre Street, Colorado Springs, CO 80903 (United States); Conley, A. [Center for Astrophysics and Space Astronomy, 389 UCB, University of Colorado, Boulder, CO 80309 (United States); Connolly, N. [Hamilton College Department of Physics, Clinton, NY 13323 (United States); Deustua, S.; Fruchter, A. S. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Fadeyev, V. [Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruze, CA 94064 (United States); Gibbons, R. A. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37240 (United States); Huang, X. [Department of Physics, University of California Berkeley, Berkeley, CA 94720 (United States); Kowalski, M. [Physikalisches Institut Universitaet Bonn (Germany); Lidman, C. [Australian Astronomical Observatory, P.O. Box 296, Epping, NSW 1710 (Australia); Collaboration: Supernova Cosmology Project; and others

    2013-01-20

    We report the discovery of a redshift 1.71 supernova in the GOODS-North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from the host or neighboring galaxies. Although the rest-frame-sampled range is too blue to include any Si II line, a principal component analysis allows us to confirm it as a Type Ia supernova with 92% confidence. A recent serendipitous archival HST WFC3 grism spectrum contributed a key element of the confirmation by giving a host-galaxy redshift of 1.713 {+-} 0.007. In addition to being the most distant SN Ia with spectroscopic confirmation, this is the most distant Ia with a precision color measurement. We present the ACS WFC and NICMOS 2 photometry and ACS and WFC3 spectroscopy. Our derived supernova distance is in agreement with the prediction of {Lambda}CDM.

  8. Ozone Depletion from Nearby Supernovae

    Science.gov (United States)

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

    2002-01-01

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

  9. Studies of LaSn{sub 3} as a negative electrode for lithium ion batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Vaughey, J. T.; Thackeray, M. M.; Shin, D.; Wolverton, C.; Northwestern Univ.

    2009-01-01

    The intermetallic compound LaSn{sub 3} has been explored as a possible negative electrode for lithium-ion batteries. A combination of experiment and density functional theory calculations provides evidence that the structure is intolerant to lithium insertion and that the electrochemical reaction occurs via a displacement mechanism. Experiment shows that approximately six Li react initially with LaSn{sub 3}; calculated energetics suggest that during the reaction La{sub 3}Sn{sub 5} and lithiated tin are formed and that the electrode operates by delithiation and relithiation of the Sn particles within an inert lanthanum-tin matrix. LaSn{sub 3} electrodes provide a reversible specific capacity of 200-250 mAh/g, whereas In-substituted electrodes that form a solid solution with LaSn{sub 3}, such as LaSn{sub 2.7}In{sub 0.3}, yield a slightly lower capacity.

  10. The Origin and Evolution of the Infrared Light Curve of SN2010jl

    Science.gov (United States)

    Dwek, Eli; Sarangi, Arkaprabha; Arendt, Richard; Fox, Ori; Kallman, Timothy; Kazanas, Demosthenes

    2018-01-01

    SN2010jl is a luminous core-collapse supernova (CCSN) of Type IIn that is surrounded by a dense circumstellar medium (CSM). The supernova (SN) luminosity vastly exceeds the available power from radiactive elements in the ejecta, and is powered by the interaction of the SN shock wave with the ambient medium. Upper limits on the UV and near-IR (NIR) emission from pre-explosion images of the region suggest that any progenitor star was hidden by pre-existing CSM dust. After day ~80, the SN spectrum shows the development of an IR excess above the extrapolated UVO emission arising from the shocked CSM. This IR component is attributed to thermal emission from dust.After day ~300, the light curve exhibits a rise in the NIR luminosity, concurrent with a steep decline at UVO wavelengths. Ruling out any possible contribution of SN-condensed dust to the IR light curve, we show that the early IR emission arises from the pre-existing CSM dust that survived the flash of radiation from the shock breakout. The late IR emission arises from newly-formed CSM dust that condensed in the cooling dust-free postshock gas of the advancing SN shock wave. Our analysis presents the first detailed modeling of dust formation in a cooling postshock environment, and provides important insights into the interaction of the SN shock wave with the CSM.

  11. A faint type of supernova from a white dwarf with a helium-rich companion

    OpenAIRE

    Perets, H.B.; Gal-Yam, A; Mazzali, P.; Arnett, D.; Kagan, D.; Filippenko, A. V.; Li, W.; Arcavi, I.; Cenko, S. B.; Fox, D. B.; Leonard, D. C.; Moon, D. -S.; Sand, D. J.; Soderberg, A. M.; Foley, R. J.

    2009-01-01

    Supernovae (SNe) are thought to arise from two different physical processes. The cores of massive, short-lived stars undergo gravitational core collapse and typically eject a few solar masses during their explosion. These are thought to appear as as type Ib/c and II SNe, and are associated with young stellar populations. A type Ia SN is thought to arise from the thermonuclear detonation of a white dwarf star composed mainly of carbon and oxygen, whose mass approaches the Chandrasekhar limit. ...

  12. Estimating dust distances to Type Ia supernovae from colour excess time evolution

    Science.gov (United States)

    Bulla, M.; Goobar, A.; Amanullah, R.; Feindt, U.; Ferretti, R.

    2018-01-01

    We present a new technique to infer dust locations towards reddened Type Ia supernovae and to help discriminate between an interstellar and a circumstellar origin for the observed extinction. Using Monte Carlo simulations, we show that the time evolution of the light-curve shape and especially of the colour excess E(B - V) places strong constraints on the distance between dust and the supernova. We apply our approach to two highly reddened Type Ia supernovae for which dust distance estimates are available in the literature: SN 2006X and SN 2014J. For the former, we obtain a time-variable E(B - V) and from this derive a distance of 27.5^{+9.0}_{-4.9} or 22.1^{+6.0}_{-3.8} pc depending on whether dust properties typical of the Large Magellanic Cloud (LMC) or the Milky Way (MW) are used. For the latter, instead, we obtain a constant E(B - V) consistent with dust at distances larger than ∼50 and 38 pc for LMC- and MW-type dust, respectively. Values thus extracted are in excellent agreement with previous estimates for the two supernovae. Our findings suggest that dust responsible for the extinction towards these supernovae is likely to be located within interstellar clouds. We also discuss how other properties of reddened Type Ia supernovae - such as their peculiar extinction and polarization behaviour and the detection of variable, blue-shifted sodium features in some of these events - might be compatible with dust and gas at interstellar-scale distances.

  13. The imprints of the last jets in core collapse supernovae

    Science.gov (United States)

    Bear, Ealeal; Grichener, Aldana; Soker, Noam

    2017-12-01

    We analyse the morphologies of three core collapse supernova remnants (CCSNRs) and the energy of jets in other CCSNRs and in Super Luminous Supernovae (SLSNe) of type Ib/Ic/IIb, and conclude that these properties are well explained by the last jets' episode as expected in the jet feedback explosion mechanism of core collapse supernovae (CCSNe). The presence of two opposite protrusions, termed ears, and our comparison of the CCSNR morphologies with morphologies of planetary nebulae strengthen the claim that jets play a major role in the explosion mechanism of CCSNe. We crudely estimate the energy that was required to inflate the ears in two CCSNRs and assume that the ears were inflated by jets. We find that the energies of the jets which inflated ears in 11 CCSNRs span a range that is similar to that of jets in some energetic CCSNe (SLSNe) and that this energy, only of the last jets' episode, is much less than the explosion energy. This finding is compatible with the jet feedback explosion mechanism of CCSNe, where only the last jets, which carry a small fraction of the total energy carried by earlier jets, are expected to influence the outer parts of the ejecta. We reiterate our call for a paradigm shift from neutrino-driven to jet-driven explosion models of CCSNe.

  14. 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] 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] 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.

  15. Constraining Cosmic Evolution of Type Ia Supernovae

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-02-13

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

  16. Mapping Circumstellar Matter with Polarized Light: The Case of Supernova 2014J in M82

    Science.gov (United States)

    Yang, Yi; Wang, Lifan; Baade, Dietrich; Brown, Peter. J.; Cikota, Aleksandar; Cracraft, Misty; Höflich, Peter A.; Maund, Justyn R.; Patat, Ferdinando; Sparks, William B.; Spyromilio, Jason; Stevance, Heloise F.; Wang, Xiaofeng; Wheeler, J. Craig

    2018-02-01

    Optical polarimetry is an effective way of probing the environment of a supernova for dust. We acquired linear HST ACS/WFC polarimetry in bands F475W, F606W, and F775W of the supernova (SN) 2014J in M82 at six epochs from ∼277 days to ∼1181 days after the B-band maximum. The polarization measured at day 277 shows conspicuous deviations from other epochs. These differences can be attributed to at least ∼{10}-6 {M}ȯ of circumstellar dust located at a distance of ∼ 5× {10}17 {cm} from the SN. The scattering dust grains revealed by these observations seem to be aligned with the dust in the interstellar medium that is responsible for the large reddening toward the supernova. The presence of this circumstellar dust sets strong constraints on the progenitor system that led to the explosion of SN 2014J; however, it cannot discriminate between single- and double-degenerate models.

  17. How Bright Can Supernovae Get?

    Science.gov (United States)

    Kohler, Susanna

    2016-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-01-08

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

  19. 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.

  20. Iron and nickel isotope compositions of presolar silicon carbide grains from supernovae

    Science.gov (United States)

    Kodolányi, János; Stephan, Thomas; Trappitsch, Reto; Hoppe, Peter; Pignatari, Marco; Davis, Andrew M.; Pellin, Michael J.

    2018-01-01

    We report the carbon, silicon, iron, and nickel isotope compositions of twenty-five presolar SiC grains of mostly supernova (SN) origin. The iron and nickel isotope compositions were measured with the new Chicago Instrument for Laser Ionization, CHILI, which allows the analysis of all iron and nickel isotopes without the isobaric interferences that plagued previous measurements with the NanoSIMS. Despite terrestrial iron and nickel contamination, significant isotopic anomalies in 54Fe/56Fe, 57Fe/56Fe, 60Ni/58Ni, 61Ni/58Ni, 62Ni/58Ni, and 64Ni/58Ni were detected in nine SN grains (of type X). Combined multi-isotope data of three grains with the largest nickel isotope anomalies (>100‰ or isotope ratio, when expressed as deviation from the solar value) are compared with the predictions of two SN models, one with and one without hydrogen ingestion in the He shell prior to SN explosion. One grain's carbon-silicon-iron-nickel isotope composition is consistent with the prediction of the model without hydrogen ingestion, whereas the other two grains' isotope anomalies could not be reproduced using either SN models. The discrepancies between the measured isotope compositions and model predictions may indicate element fractionation in the SN ejecta prior to or during grain condensation, and reiterate the need for three-dimensional SN models.

  1. VizieR Online Data Catalog: UBVRI light curves of SN 2009E (Pastorello+, 2012)

    Science.gov (United States)

    Pastorello, A.; Pumo, M. L.; Navasardyan, H.; Zampieri, L.; Turatto, M.; Sollerman, J.; Taddia, F.; Kankare, E.; Mattila, S.; Nicolas, J.; Prosperi, E.; San Segundo Delgado, A.; Taubenberger, S.; Boles, T.; Bachini, M.; Benetti, S.; Bufano, F.; Cappellaro, E.; Cason, A. D.; Cetrulo, G.; Ergon, M.; Germany, L.; Harutyunyan, A.; Howerton, S.; Hurst, G. M.; Patat, F.; Stritzinger, M.; Strolger, L.-G.; Wells, W.

    2011-11-01

    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. In this paper we investigate the properties of SN 2009E, which exploded in a relatively nearby spiral galaxy (NGC 4141) and that is probably the faintest 1987A-like supernova discovered so far. We also attempt to characterize this subgroup of core-collapse supernovae with the help of the literature and present new data for a few additional objects. The lack of early-time observations from professional telescopes is compensated by frequent follow-up observations performed by a number of amateur astronomers. This allows us to reconstruct a well-sampled light curve for SN 2009E. Spectroscopic observations which started about 2 months after the supernova explosion, highlight significant differences between SN 2009E and the prototypical SN 1987A. Modelling the data of SN 2009E allows us to constrain the explosion parameters and the properties of the progenitor star, and compare the inferred estimates with those available for the similar SNe 1987A and 1998A. The light curve of SN 2009E is less luminous than that of SN 1987A and the other members of this class, and the maximum light curve peak is reached at a slightly later epoch than in SN 1987A. Late-time photometric observations suggest that SN 2009E ejected about 0.04M⊙ of 56Ni, which is the smallest 56Ni mass in our sample of 1987A-like events. Modelling the observations with a radiation hydrodynamics code, we infer for SN 2009E a kinetic plus thermal energy of about 0.6 foe, an initial radius of ~7x1012cm and an ejected mass of ~19M⊙. The photospheric spectra show a number of narrow (v~1800km/s) metal lines, with unusually strong BaII lines. The nebular spectrum displays narrow emission lines of H, NaI, [CaII] and [OI], with the [OI

  2. Supernova Explosions Stay In Shape

    Science.gov (United States)

    2009-12-01

    At a very early age, children learn how to classify objects according to their shape. Now, new research suggests studying the shape of the aftermath of supernovas may allow astronomers to do the same. A new study of images from NASA's Chandra X-ray Observatory on supernova remnants - the debris from exploded stars - shows that the symmetry of the remnants, or lack thereof, reveals how the star exploded. This is an important discovery because it shows that the remnants retain information about how the star exploded even though hundreds or thousands of years have passed. "It's almost like the supernova remnants have a 'memory' of the original explosion," said Laura Lopez of the University of California at Santa Cruz, who led the study. "This is the first time anyone has systematically compared the shape of these remnants in X-rays in this way." Astronomers sort supernovas into several categories, or "types", based on properties observed days after the explosion and which reflect very different physical mechanisms that cause stars to explode. But, since observed remnants of supernovas are leftover from explosions that occurred long ago, other methods are needed to accurately classify the original supernovas. Lopez and colleagues focused on the relatively young supernova remnants that exhibited strong X-ray emission from silicon ejected by the explosion so as to rule out the effects of interstellar matter surrounding the explosion. Their analysis showed that the X-ray images of the ejecta can be used to identify the way the star exploded. The team studied 17 supernova remnants both in the Milky Way galaxy and a neighboring galaxy, the Large Magellanic Cloud. For each of these remnants there is independent information about the type of supernova involved, based not on the shape of the remnant but, for example, on the elements observed in it. The researchers found that one type of supernova explosion - the so-called Type Ia - left behind relatively symmetric, circular

  3. ANALYTIC APPROXIMATION OF CARBON CONDENSATION ISSUES IN TYPE II SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, Donald D., E-mail: claydonald@gmail.com [Department of Physics and Astronomy, Clemson University, Clemson, SC (United States)

    2013-01-01

    I present analytic approximations for some issues related to condensation of graphite, TiC, and silicon carbide in oxygen-rich cores of supernovae of Type II. Increased understanding, which mathematical analysis can support, renders researchers more receptive to condensation in O-rich supernova gases. Taking SN 1987A as typical, my first analysis shows why the abundance of CO molecules reaches an early maximum in which free carbon remains more abundant than CO. This analysis clarifies why O-rich gas cannot oxidize C if {sup 56}Co radioactivity is as strong as in SN 1987A. My next analysis shows that the CO abundance could be regarded as being in chemical equilibrium if the CO molecule is given an effective binding energy rather than its laboratory dissociation energy. The effective binding energy makes the thermal dissociation rate of CO equal to its radioactive dissociation rate. This preserves possible relevance for the concept of chemical equilibrium. My next analysis shows that the observed abundances of CO and SiO molecules in SN 1987A rule out frequent suggestions that equilibrium condensation of SUNOCONs has occurred following atomic mixing of the He-burning shell with more central zones in such a way as to reproduce roughly the observed spectrum of isotopes in SUNOCONs while preserving C/O > 1. He atoms admixed along with the excess carbon would destroy CO and SiO molecules, leaving their observed abundances unexplained. The final analysis argues that a chemical quasiequilibrium among grains (but not gas) may exist approximately during condensation, so that its computational use is partially justified as a guide to which mineral phases would be stable against reactions with gas. I illustrate this point with quasiequilibrium calculations by Ebel and Grossman that have shown that graphite is stable even when O/C >1 if prominent molecules are justifiably excluded from the calculation of chemical equilibrium.

  4. Optical and Near-Infrared Observations of SN 2013DX Associated with GRB 130702A

    Science.gov (United States)

    Toy, V. L.; Cenko, S. B.; Silverman, J. M.; Butler, N. R.; Cucchiara, A.; Watson, A. M.; Bersier, D.; Perley, D. A.; Margutti, R.; Bellm, E.; hide

    2016-01-01

    We present optical and near-infrared (NIR) light curves and optical spectra of SN 2013dx, associated with the nearby (redshift 0.145) gamma-ray burst GRB 130702A. The prompt isotropic gamma-ray energy released from GRB 130702A is measured to be E(sub gamma, iso) = 6.4(+1.3/-1.0) x 10(exp 50) erg (1 keV to 10 MeV in the rest frame), placing it intermediate between low-luminosity GRBs like GRB 980425/SN 1998bw and the broader cosmological population. We compare the observed g'r'i'z' light curves of SN 2013dx to a SN 1998bw template, finding that SN 2013dx evolves approx. 20% faster (steeper rise time), with a comparable peak luminosity. Spectroscopically, SN 2013dx resembles other broad-lined SNe Ic, both associated with (SN 2006aj and SN 1998bw) and lacking (SN 1997ef, SN 2007I, and SN 2010ah) gamma-ray emission, with photospheric velocities around peak of approx. 21,000 km/s. We construct a quasi-bolometric (g'r'z'yJ) light curve for SN 2013dx, only the fifth GRB-associated SN with extensive NIR coverage and the third with a bolometric light curve extending beyond (Delta)t > 40 days. Together with the measured photospheric velocity, we derive basic explosion parameters using simple analytic models. We infer a Ni-56 mass of M(sub Ni) = 0.37+/- 0.01 Stellar Mass, an ejecta mass of M(sub ej) = 3.1+/- 0.1 Stellar Mass, and a kinetic energy of E(sub K) = (8.2+/- 0.43) x 10(exp 51) erg (statistical uncertainties only), consistent with previous GRB-associated supernovae. When considering the ensemble population of GRB-associated supernovae, we find no correlation between the mass of synthesized Ni-56 and high-energy properties, despite clear predictions from numerical simulations that M(sub Ni) should correlate with the degree of asymmetry. On the other hand, M(sub Ni) clearly correlates with the kinetic energy of the supernova ejecta across a wide range of core-collapse events.

  5. Supernova Physics at DUNE

    CERN Document Server

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

    2016-01-01

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

  6. Energetics Laboratory Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — These energetic materials laboratories are equipped with explosion proof hoods with blow out walls for added safety, that are certified for safe handling of primary...

  7. Critical ingredients of Type Ia supernova radiative-transfer modelling

    Science.gov (United States)

    Dessart, Luc; Hillier, D. John; Blondin, Stéphane; Khokhlov, Alexei

    2014-07-01

    We explore the physics of Type Ia supernova (SN Ia) light curves and spectra using the 1D non-local thermodynamic equilibrium (non-LTE) time-dependent radiative-transfer code CMFGEN. Rather than adjusting ejecta properties to match observations, we select as input one `standard' 1D Chandrasekhar-mass delayed-detonation hydrodynamical model, and then explore the sensitivity of radiation and gas properties of the ejecta on radiative-transfer modelling assumptions. The correct computation of SN Ia radiation is not exclusively a solution to an `opacity problem', characterized by the treatment of a large number of lines. We demonstrate that the key is to identify and treat important atomic processes consistently. This is not limited to treating line blanketing in non-LTE. We show that including forbidden-line transitions of metals, and in particular Co, is increasingly important for the temperature and ionization of the gas beyond maximum light. Non-thermal ionization and excitation are also critical since they affect the colour evolution and the ΔM15 decline rate of our model. While impacting little the bolometric luminosity, a more complete treatment of decay routes leads to enhanced line blanketing, e.g. associated with 48Ti in the U and B bands. Overall, we find that SN Ia radiation properties are influenced in a complicated way by the atomic data we employ, so that obtaining converged results is a real challenge. Nonetheless, with our fully fledged CMFGEN model, we obtain good agreement with the golden standard Type Ia SN 2005cf in the optical and near-IR, from 5 to 60 d after explosion, suggesting that assuming spherical symmetry is not detrimental to SN Ia radiative-transfer modelling at these times. Multi-D effects no doubt matter, but they are perhaps less important than accurately treating the non-LTE processes that are crucial to obtain reliable temperature and ionization structures.

  8. Extremely late photometry of the nearby SN 2011fe

    Science.gov (United States)

    Kerzendorf, W. E.; McCully, C.; Taubenberger, S.; Jerkstrand, A.; Seitenzahl, I.; Ruiter, A. J.; Spyromilio, J.; Long, K. S.; Fransson, C.

    2017-12-01

    Type Ia supernovae are widely accepted to be the outcomes of thermonuclear explosions in white dwarf stars. However, many details of these explosions remain uncertain (e.g. the mass, ignition mechanism and flame speed). Theory predicts that at very late times (beyond 1000 d) it might be possible to distinguish between explosion models. Few very nearby supernovae can be observed that long after the explosion. The Type Ia supernova SN 2011fe located in M101 and along a line of sight with negligible extinction, provides us with the once-in-a-lifetime chance to obtain measurements that may distinguish between theoretical models. In this work, we present the analysis of photometric data of SN 2011fe taken between 900 and 1600 d after explosion with Gemini and HST. At these extremely late epochs theory suggests that the light-curve shape might be used to measure isotopic abundances which is a useful model discriminant. However, we show in this work that there are several currently not well constrained physical processes introducing large systematic uncertainties to the isotopic abundance measurement. We conclude that without further detailed knowledge of the physical processes at this late stage one cannot reliably exclude any models on the basis of this data set.

  9. Energetic eruptions leading to a peculiar hydrogen-rich explosion of a massive star

    Science.gov (United States)

    Arcavi, Iair; Howell, D. Andrew; Kasen, Daniel; Bildsten, Lars; Hosseinzadeh, Griffin; McCully, Curtis; Wong, Zheng Chuen; Katz, Sarah Rebekah; Gal-Yam, Avishay; Sollerman, Jesper; Taddia, Francesco; Leloudas, Giorgos; Fremling, Christoffer; Nugent, Peter E.; Horesh, Assaf; Mooley, Kunal; Rumsey, Clare; Cenko, S. Bradley; Graham, Melissa L.; Perley, Daniel A.; Nakar, Ehud; Shaviv, Nir J.; Bromberg, Omer; Shen, Ken J.; Ofek, Eran O.; Cao, Yi; Wang, Xiaofeng; Huang, Fang; Rui, Liming; Zhang, Tianmeng; Li, Wenxiong; Li, Zhitong; Zhang, Jujia; Valenti, Stefano; Guevel, David; Shappee, Benjamin; Kochanek, Christopher S.; Holoien, Thomas W.-S.; Filippenko, Alexei V.; Fender, Rob; Nyholm, Anders; Yaron, Ofer; Kasliwal, Mansi M.; Sullivan, Mark; Blagorodnova, Nadja; Walters, Richard S.; Lunnan, Ragnhild; Khazov, Danny; Andreoni, Igor; Laher, Russ R.; Konidaris, Nick; Wozniak, Przemek; Bue, Brian

    2017-11-01

    Every supernova so far observed has been considered to be the terminal explosion of a star. Moreover, all supernovae with absorption lines in their spectra show those lines decreasing in velocity over time, as the ejecta expand and thin, revealing slower-moving material that was previously hidden. In addition, every supernova that exhibits the absorption lines of hydrogen has one main light-curve peak, or a plateau in luminosity, lasting approximately 100 days before declining. Here we report observations of iPTF14hls, an event that has spectra identical to a hydrogen-rich core-collapse supernova, but characteristics that differ extensively from those of known supernovae. The light curve has at least five peaks and remains bright for more than 600 days; the absorption lines show little to no decrease in velocity; and the radius of the line-forming region is more than an order of magnitude bigger than the radius of the photosphere derived from the continuum emission. These characteristics are consistent with a shell of several tens of solar masses ejected by the progenitor star at supernova-level energies a few hundred days before a terminal explosion. Another possible eruption was recorded at the same position in 1954. Multiple energetic pre-supernova eruptions are expected to occur in stars of 95 to 130 solar masses, which experience the pulsational pair instability. That model, however, does not account for the continued presence of hydrogen, or the energetics observed here. Another mechanism for the violent ejection of mass in massive stars may be required.

  10. The Type Ia Supernova Rate at z~0.5 from the Supernova Legacy Survey

    Science.gov (United States)

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

    2006-09-01

    We present a measurement of the distant Type Ia supernova (SN Ia) rate derived from the first 2 yr of the Canada-France-Hawaii Telescope Supernova Legacy Survey. We observed four 1deg×1deg fields with a typical temporal frequency of ~4 observer-frame days over time spans of 158-211 days per season for each field, with breaks during the full Moon. We used 8-10 m class telescopes for spectroscopic follow-up to confirm our candidates and determine their redshifts. Our starting sample consists of 73 spectroscopically verified SNe Ia in the redshift range 0.2=0.47)=[0.42+0.13-0.09(syst.)+/-0.06(stat.)×10-4 yr-1 Mpc3, assuming h=0.7, Ωm=0.3, and a flat cosmology. Using recently published galaxy luminosity functions derived in our redshift range, we derive a SN Ia rate per unit luminosity of rL(=0.47)=0.154+0.048-0.033(syst.)+0.039-0.031(stat.) SN units. Using our rate alone, we place an upper limit on the component of SN Ia production that tracks the cosmic star formation history of 1 SN Ia per 103 Msolar of stars formed. Our rate and other rates from surveys using spectroscopic sample confirmation display only a modest evolution out to z=0.55. Based on observations obtained with MegaPrime/MegaCam, a joint project of the Canada-France-Hawaii Telescope (CFHT) and CEA/DAPNIA, at CFHT, which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. This work is also based on observations obtained at the European Southern Observatory using the Very Large Telescope on the Cerro Paranal (ESO Large Program 171.A-0486), and on observations (programs GN-2004A-Q-19, GS-2004A-Q-11, GN-2003B-Q-9, and GS-2003B-Q-8) obtained at the Gemini

  11. Supernova Neutrino Detection With Liquid Scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Ianni, Aldo, E-mail: aldo.ianni@lngs.infn.it [I.N.F.N. Gran Sasso Laboratory, S.S. 17bis, 67100, Assergi (Italy)

    2011-08-10

    Core collapse supernovae are a remarkable source of neutrinos. These neutrinos can also be detected by means of massive liquid scintillators located underground. Observations of supernova neutrinos can shed light on the explosion mechanism and on neutrino properties. In this paper we review the detection channels for neutrinos in liquid scintillators. We consider present and future experiments for supernova neutrino searches.

  12. The Core-Collapse Supernova Explosion Mechanism

    Science.gov (United States)

    Müller, Bernhard

    2017-11-01

    The explosion mechanism of core-collapse supernovae is a long-standing problem in stellar astrophysics. We briefly outline the main contenders for a solution and review recent efforts to model core-collapse supernova explosions by means of multi-dimensional simulations. Focusing on the neutrino-driven mechanism, we summarize currents efforts to predict supernova explosion and remnant properties.

  13. Type IA supernovae: Their progenitors and use as cosmological probes

    Science.gov (United States)

    Patel, Brandon

    Type Ia supernovae (SNe Ia) are important cosmological probes, but we are uncertain how they explode. There are two progenitor channels for SNe Ia: single and double degenerate white dwarf (WD) systems. In either model, we expect the system to be detectable as a Supersoft X-ray Source (SSS) for a significant amount of time before the explosion. By studying these SSSs, we hope to improve our understanding of SNe Ia. In Chapter 2, we analyze an interesting source (r1-25) in M31. We found that the source exhibited spectral changes to harder X-ray states. r1-25 is the first source of its kind, and we require unique physical models to fit its behavior. We find that existing WD models are inconsistent with the spectra of the source. We explore new black hole and neutron star models, and find that they can model the unusual behavior of r1-25. In Chapter 3, we study three gravitationally lensed SNe from the Cluster Lensing And Supernova survey with Hubble (CLASH). Based on photometric classification, we found that two SNe (SN CLO12Car and CLN12Did) are likely to be SNe Ia, while the classification of the third is inconclusive. Using multi-color light-curve fits to determine a standardized SN Ia luminosity distance, we infer that SN CLO12Car was ˜ 1.0 +/- 0.2 mag brighter than field SNe Ia at a similar redshift and ascribe this to gravitational lens magnification. Similarly, SN CLN12Did is ˜ 0.2 +/- 0.2 mag brighter than field SNe Ia. From independent CLASH strong+weak lensing maps of the clusters , we derived similar magnifications for the two SNe Ia. The two SNe Ia provide a new test of the cluster lens model predictions: we find that the magnifications based on the SN Ia brightness and those predicted by the lens maps are consistent. Finally, in Chapter 4 we discuss a new light curve fitter for SNe Ia, which we call Multicolor Light Curve Shapes 3 (MLCS3). The project has not been completed, but we discuss some of the features, and the expected improvements from MLCS3

  14. The Carnegie Supernova Project. I. Third Photometry Data Release of Low-redshift Type Ia Supernovae and Other White Dwarf Explosions

    Science.gov (United States)

    Krisciunas, Kevin; Contreras, Carlos; Burns, Christopher R.; Phillips, M. M.; Stritzinger, Maximilian D.; Morrell, Nidia; Hamuy, Mario; Anais, Jorge; Boldt, Luis; Busta, Luis; Campillay, Abdo; Castellón, Sergio; Folatelli, Gastón; Freedman, Wendy L.; González, Consuelo; Hsiao, Eric Y.; Krzeminski, Wojtek; Persson, Sven Eric; Roth, Miguel; Salgado, Francisco; Serón, Jacqueline; Suntzeff, Nicholas B.; Torres, Simón; Filippenko, Alexei V.; Li, Weidong; Madore, Barry F.; DePoy, D. L.; Marshall, Jennifer L.; Rheault, Jean-Philippe; Villanueva, Steven

    2017-11-01

    We present final natural-system optical (ugriBV) and near-infrared (YJH) photometry of 134 supernovae (SNe) with probable white dwarf progenitors that were observed in 2004-2009 as part of the first stage of the Carnegie Supernova Project (CSP-I). The sample consists of 123 Type Ia SNe, 5 Type Iax SNe, 2 super-Chandrasekhar SN candidates, 2 Type Ia SNe interacting with circumstellar matter, and 2 SN 2006bt-like events. The redshifts of the objects range from z=0.0037 to 0.0835; the median redshift is 0.0241. For 120 (90%) of these SNe, near-infrared photometry was obtained. Average optical extinction coefficients and color terms are derived and demonstrated to be stable during the five CSP-I observing campaigns. Measurements of the CSP-I near-infrared bandpasses are also described, and near-infrared color terms are estimated through synthetic photometry of stellar atmosphere models. Optical and near-infrared magnitudes of local sequences of tertiary standard stars for each supernova are given, and a new calibration of Y-band magnitudes of the Persson et al. standards in the CSP-I natural system is presented.

  15. Red supergiants as supernova progenitors

    Science.gov (United States)

    Davies, Ben

    2017-09-01

    It is now well-established from pre-explosion imaging that red supergiants (RSGs) are the direct progenitors of Type-IIP supernovae. These images have been used to infer the physical properties of the exploding stars, yielding some surprising results. In particular, the differences between the observed and predicted mass spectrum has provided a challenge to our view of stellar evolutionary theory. However, turning what is typically a small number of pre-explosion photometric points into the physical quantities of stellar luminosity and mass requires a number of assumptions about the spectral appearance of RSGs, as well as their evolution in the last few years of life. Here I will review what we know about RSGs, with a few recent updates on how they look and how their appearance changes as they approach supernova. This article is part of the themed issue 'Bridging the gap: from massive stars to supernovae'.

  16. The IceCube data acquisition system for galactic core collapse supernova searches

    Energy Technology Data Exchange (ETDEWEB)

    Baum, Volker [Institute of Physics, University of Mainz, Staudinger Weg 7, D-55099 Mainz (Germany); Collaboration: IceCube Collaboration

    2014-11-18

    The IceCube Neutrino Observatory was designed to detect highly energetic neutrinos. The detector was built as a lattice of 5160 photomultiplier tubes monitoring one cubic kilometer of clear Antarctic ice. Due to low photomultiplier dark noise rates in the cold and radio-pure ice, IceCube is also able to detect bursts of O(10MeV) neutrinos expected to be emitted from core collapse supernovae. The detector will provide the world’s highest statistical precision for the lightcurves of galactic supernovae by observing an induced collective rise in all photomultiplier rates [1]. This paper presents the supernova data acquisition system, the search algorithms for galactic supernovae, as well as the recently implemented HitSpooling DAQ extension. HitSpooling will overcome the current limitation of transmitting photomultiplier rates in intervals of 1.6384 ms by storing all recorded time-stamped hits for supernova candidate triggers. From the corresponding event-based information, the average neutrino energy can be estimated and the background induced by detector noise and atmospheric muons can be reduced.

  17. Extreme Environments: From supermassive black holes to supernovae

    Science.gov (United States)

    Krauss, Felicia

    2016-06-01

    In this work I study X-ray observations as a tool of distinguishing between models of supernovae type Ia and relativistic jets - collimated outflows of matter from active galactic nuclei (AGN). Supernovae type Ia are thermonuclear runaways that are expected to originate from either a merger of two white dwarfs or from an accreting white dwarf in a binary system with a massive star. The first models challenges supernovae type Ia as standard candles for distance measurements. In an accreting system, the white dwarf is expected to undergo the thermonuclear runaway when reaching the Chandrasekhar mass. In a merger of two white dwarves the final mass would differ from supernova to supernova, leading to varying luminosities and subsequent errors in the distance calculations. The accretion model predicts a higher amount of 55Co, which synthesizes 3.5 times more radioactive 55Fe. The resulting line doublet is emitted at 5.888 keV and 5.899 keV. I study current and future X-ray missions as a tool for distinguishing between both models by measuring the line flux. My simulations show that with the current satellite Chandra, the models can be distinguished up to a distance of 2 Mpc, within the local group. The proposed Athena mission holds promise for a detection of the 5.9 keV line for the accretion model of distances up to 5 Mpc. The recent supernova SN2014J in January 2014 was the closest supernova in four decades with a distance of 3.5 Mpc. At the highest expected 55Fe line flux it could not be observed by either XMM-Newton or Chandra. In the remaining work I study jets from active galactic nuclei (AGN) using broadband observations from the radio band to high-energy gamma-rays. Jets are powerful, persistent, and luminous phenomena and are not fully understood, especially their jet launching, confinement and particle acceleration. Blazars are a subclass of AGN, with the jet pointed at a small angle to the line of sight, which allows to directly study the emission mechanisms

  18. Early Blue Excess from the Type Ia Supernova 2017cbv and Implications for Its Progenitor

    Energy Technology Data Exchange (ETDEWEB)

    Hosseinzadeh, Griffin; Howell, D. Andrew; McCully, Curtis; Arcavi, Iair [Las Cumbres Observatory, 6740 Cortona Drive, Suite 102, Goleta, CA 93117-5575 (United States); Sand, David J.; Tartaglia, Leonardo [Department of Astronomy/Steward Observatory, 933 North Cherry Avenue, Room N204, Tucson, AZ 85721-0065 (United States); Valenti, Stefano; Bostroem, K. Azalee [Department of Physics, University of California, 1 Shields Avenue, Davis, CA 95616-5270 (United States); Brown, Peter [Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, TX 77843-4242 (United States); Kasen, Daniel [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720-8169 (United States); Hsiao, Eric Y.; Davis, Scott; Shahbandeh, Melissa [Department of Physics, Florida State University, 77 Chieftain Way, Tallahassee, FL 32306-4350 (United States); Stritzinger, Maximilian D., E-mail: griffin@lco.global [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark)

    2017-08-20

    We present very early, high-cadence photometric observations of the nearby Type Ia SN 2017cbv. The light curve is unique in that it has a blue bump during the first five days of observations in the U , B , and g bands, which is clearly resolved given our photometric cadence of 5.7 hr during that time span. We model the light curve as the combination of early shocking of the supernova ejecta against a nondegenerate companion star plus a standard SN Ia component. Our best-fit model suggests the presence of a subgiant star 56 R {sub ☉} from the exploding white dwarf, although this number is highly model-dependent. While this model matches the optical light curve well, it overpredicts the observed flux in the ultraviolet bands. This may indicate that the shock is not a blackbody, perhaps because of line blanketing in the UV. Alternatively, it could point to another physical explanation for the optical blue bump, such as interaction with circumstellar material or an unusual nickel distribution. Early optical spectra of SN 2017cbv show strong carbon (C ii λ 6580) absorption up through day −13 with respect to maximum light, suggesting that the progenitor system contains a significant amount of unburned material. These early results on SN 2017cbv illustrate the power of early discovery and intense follow-up of nearby supernovae to resolve standing questions about the progenitor systems and explosion mechanisms of SNe Ia.

  19. Early Blue Excess from the Type Ia Supernova 2017cbv and Implications for Its Progenitor

    Science.gov (United States)

    Hosseinzadeh, Griffin; Sand, David J.; Valenti, Stefano; Brown, Peter; Howell, D. Andrew; McCully, Curtis; Kasen, Daniel; Arcavi, Iair; Azalee Bostroem, K.; Tartaglia, Leonardo; Hsiao, Eric Y.; Davis, Scott; Shahbandeh, Melissa; Stritzinger, Maximilian D.

    2017-08-01

    We present very early, high-cadence photometric observations of the nearby Type Ia SN 2017cbv. The light curve is unique in that it has a blue bump during the first five days of observations in the U, B, and g bands, which is clearly resolved given our photometric cadence of 5.7 hr during that time span. We model the light curve as the combination of early shocking of the supernova ejecta against a nondegenerate companion star plus a standard SN Ia component. Our best-fit model suggests the presence of a subgiant star 56 R ⊙ from the exploding white dwarf, although this number is highly model-dependent. While this model matches the optical light curve well, it overpredicts the observed flux in the ultraviolet bands. This may indicate that the shock is not a blackbody, perhaps because of line blanketing in the UV. Alternatively, it could point to another physical explanation for the optical blue bump, such as interaction with circumstellar material or an unusual nickel distribution. Early optical spectra of SN 2017cbv show strong carbon (C ii λ6580) absorption up through day -13 with respect to maximum light, suggesting that the progenitor system contains a significant amount of unburned material. These early results on SN 2017cbv illustrate the power of early discovery and intense follow-up of nearby supernovae to resolve standing questions about the progenitor systems and explosion mechanisms of SNe Ia.

  20. Generalized Chaplygin Gas Models Tested with Type Ia Supernovae

    Science.gov (United States)

    Biesiada, Marek; Godłowski, Włodzimierz; Szydłowski, Marek

    2005-03-01

    The generalized Chaplygin gas (GCG), with the equation of state p=-A/ρα, was recently proposed as a candidate for dark energy in the universe. In this paper we confront the GCG with Type Ia supernova (SN Ia) data using available samples. Specifically, we have tested the GCG cosmology in three different classes of models with (1) Ωm=0.3 and ΩCh=0.7, (2) Ωm=0.05 and ΩCh=0.95, and (3) Ωm=0 and ΩCh=1, as well as a model without prior assumptions on Ωm. The best-fit models are obtained by minimizing the χ2 function. We supplement our analysis with confidence intervals in the (A0, α)-plane by marginalizing the probability density functions (pdf's) over the remaining parameters assuming uniform priors. We have also derived one-dimensional pdf's for ΩCh obtained from joint marginalization over α and A0. The maximum value of such a pdf provides the most probable value of ΩCh within the full class of GCG models. The general conclusion is that SN Ia data give support to the Chaplygin gas (with α=1). However, a noticeable preference for A0-values close to 1 means that the α dependence becomes insignificant. This is reflected in one-dimensional pdf's for α that turned out to be flat, meaning that the power of the present supernova data to discriminate between various GCG models (differing by α) is weak. Extending our analysis by relaxing the prior assumption of the flatness of the universe leads to the result that even though the best-fit values of Ωk are formally nonzero, they are still close to the flat case. Our results show clearly that in GCG cosmology, distant (i.e., z>1) supernovae should be brighter than in the ΛCDM model. Therefore, one can expect that future supernova experiments (e.g., SNAP) having access to higher redshifts will eventually resolve the issue of whether the dark energy content of the universe could be described as a Chaplygin gas. Moreover, it would be possible to differentiate between models with various values of the

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

    Science.gov (United States)

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

    2016-11-01

    Previous studies have shown that the radiation emitted by a rapidly rotating magnetar embedded in a young supernova can greatly amplify its luminosity. These one-dimensional studies have also revealed the existence of an instability arising from the piling up of radiatively accelerated matter in a thin dense shell deep inside the supernova. Here, we examine the problem in two dimensions and find that, while instabilities cause mixing and fracture this shell into filamentary structures that reduce the density contrast, the concentration of matter in a hollow shell persists. The extent of the mixing depends upon the relative energy input by the magnetar and the kinetic energy of the inner ejecta. The light curve and spectrum of the resulting supernova will be appreciably altered, as will the appearance of the supernova remnant, which will be shellular and filamentary. A similar pile up and mixing might characterize other events where energy is input over an extended period by a centrally concentrated source, e.g., a pulsar, radioactive decay, a neutrino-powered wind, or colliding shells. The relevance of our models to the recent luminous transient ASASSN-15lh is briefly discussed.

  2. The surviving companions in type Ia supernova remnants

    Science.gov (United States)

    Chen, Li-Qing; Meng, Xiang-Cun; Han, Zhan-Wen

    2017-08-01

    The single-degenerate (SD) model is one of the most popular progenitor models of type Ia supernovae (SNe Ia), in which the companion star can survive after an SN Ia explosion and show peculiar properties. Therefore, searching for the surviving companion in type Ia supernova remnants (SNRs) is a potential method to verify the SD model. In the SN 1604 remnant (Kepler’s SNR), although Chandra X-ray observation suggests that the progenitor is most likely a WD+AGB system, a the surviving companion has not been found. One possible reason is rapid rotation of the white dwarf (WD), causing explosion of the WD to be delayed for a spin-down timescale, and then the companion evolved into a WD before the supernova explosion, so the companion is too dim to be detected. We aim to verify this possible explanation by carrying out binary evolution calculations. In this paper, we use Eggleton’s stellar evolution code to calculate the evolution of binaries consisting of a WD+red giant (RG). We assume that the rapidly rotating WD can continuously increase its mass when its mass exceeds the Chandrasekhar mass limit ({M}{{Ch}}=1.378 {M}⊙ ) until the mass-transfer rate decreases to be lower than a critical value. Eventually, we obtain the final masses of a WD in the range 1.378 M ⊙ to 2.707 M ⊙. We also show that if the spin-down time is less than 106 yr, the companion star will be very bright and easily observed; but if the spin-down time is as long as ˜ 107 yr, the luminosities of the surviving companion would be lower than the detection limit. Our simulation provides guidance in hunting for the surviving companion stars in SNRs, and the fact that no surviving companion has been found in Kepler’s SNR may not be definite evidence disfavoring the SD origin of Kepler’s SN.

  3. Upper limit to the 45-MHz flux density of SN 1987A

    Science.gov (United States)

    Alvarez, H.; Aparici, J.; May, J.; Olmos, F.

    1992-04-01

    Results are presented of an observational study of SN 1987A at 45 MHz using two techniques based on the assumption that the object will exhibit scintillation when its radiation gets through. On the basis of the theory developed for four well studied radio supernova and under the assumption that SN 1987A would behave like some of them, a detection at a level of several tens of Jy within the first two years of age was expected. The present results indicate that the flux density of SN 1987A was less than 5 Jy. From the nondetection it is inferred that SN 1987A did not behave like the radio supernova used for comparison, that the theory used is not applicable at very low frequencies, or that both statements may be valid. Under the assumption that the supernova is a compact source, it is estimated that a magnetic field of about 0.0001 would be sufficient to reduce the 45-MHZ radiation below 5 Jy.

  4. Confronting Alternative Cosmological Models with the Highest-Redshift Type Ia Supernovae

    Science.gov (United States)

    Shafer, Daniel; Scolnic, Daniel; Riess, Adam

    2018-01-01

    High-redshift Type Ia supernovae (SNe Ia) from the HST CANDELS and CLASH programs significantly extend the Hubble diagram with 7 SNe at z > 1.5 suitable for cosmology, including one at z = 2.3. This unique leverage helps us distinguish "alternative" cosmological models from the standard Lambda-CDM model. Analyzing the Pantheon SN compilation, which includes these high-z SNe, we employ model comparison statistics to quantify the extent to which several proposed alternative expansion histories (e.g., empty universe, power law expansion, timescape cosmology) are disfavored even with SN Ia data alone. Using mock data, we demonstrate that some likelihood analyses used in the literature to support these models are sensitive to unrealistic assumptions and are therefore unsuitable for analysis of realistic SN Ia data.

  5. Gravitational Wave Emission from the Single-Degenerate Channel of Type Ia Supernovae

    Science.gov (United States)

    Falta, David; Fisher, Robert; Khanna, Gaurav

    2011-05-01

    The thermonuclear explosion of a C/O white dwarf as a Type Ia supernova (SN Ia) generates a kinetic energy comparable to that released by a massive star during a SN II event. Current observations and theoretical models have established that SNe Ia are asymmetric, and therefore—like SNe II—potential sources of gravitational wave (GW) radiation. We perform the first detailed calculations of the GW emission for a SN Ia of any type within the single-degenerate channel. The gravitationally confined detonation (GCD) mechanism predicts a strongly polarized GW burst in the frequency band around 1 Hz. Third-generation spaceborne GW observatories currently in planning may be able to detect this predicted signal from SNe Ia at distances up to 1 Mpc. If observable, GWs may offer a direct probe into the first few seconds of the SNe Ia detonation.

  6. High angular resolution radio and infrared view of optically dark supernovae in luminous infrared galaxies

    Science.gov (United States)

    Mattila, Seppo; Kankare, Erkki; Kool, Erik; Romero-Cañizales, Cristina; Ryder, Stuart; Perez-Torres, Miguel

    2017-11-01

    In luminous and ultraluminous infrared galaxies (U/LIRGs), the infall of gas into the central regions strongly enhances the star formation rate (SFR), especially within the nuclear regions which have also large amounts of interstellar dust. Within these regions SFRs of several tens to hundreds of solar masses per year ought to give rise to core-collapse supernova (SN) rates up to 1-2 SNe every year per galaxy. However, the current SN surveys, almost exclusively being ground-based seeing-limited and working at optical wavelengths, have been blinded by the interstellar dust and contrast issues therein. Thus the properties and rates of SNe in the nuclear environments of the most prolific SN factories in the Universe have remained largely unexplored. Here, we present results from high angular resolution observations of nearby LIRGs at infrared and radio wavelengths much less affected by the effects of extinction and lack of resolution hampering the optical searches.

  7. Uncertainties in Core Collapse Supernovae Simulations

    Science.gov (United States)

    Duggan, Jefferson; Cunningham, J.; Kuhlmann, S.; Biswas, R.; Kovacs, E.; Spinka, H.

    2013-01-01

    We present the results of a study of selection criteria to identify Type Ia supernovae photometrically in a simulated mixed sample of Type Ia supernovae and core collapse supernovae. The simulated sample is a mockup of the expected results of the Dark Energy Survey (DES) using the supernovae simulation and fitting package of SNANA [Kessler et al. arXiv:0908.4280]. This is an extension of a previous analysis, [Gjergo et al. arXiv:1205.1480], with updated core collapse templates that are used to simulate the supernovae. We have also studied how systematic variations in the input parameters of the core collapse supernovae, such as absolute brightness and brightness smearing, affect the measured purity of the Type Ia supernova sample.

  8. Euclid: Superluminous supernovae in the Deep Survey

    Science.gov (United States)

    Inserra, C.; Nichol, R. C.; Scovacricchi, D.; Amiaux, J.; Brescia, M.; Burigana, C.; Cappellaro, E.; Carvalho, C. S.; Cavuoti, S.; Conforti, V.; Cuillandre, J.-C.; da Silva, A.; De Rosa, A.; Della Valle, M.; Dinis, J.; Franceschi, E.; Hook, I.; Hudelot, P.; Jahnke, K.; Kitching, T.; Kurki-Suonio, H.; Lloro, I.; Longo, G.; Maiorano, E.; Maris, M.; Rhodes, J. D.; Scaramella, R.; Smartt, S. J.; Sullivan, M.; Tao, C.; Toledo-Moreo, R.; Tereno, I.; Trifoglio, M.; Valenziano, L.

    2018-01-01

    Context. In the last decade, astronomers have found a new type of supernova called superluminous supernovae (SLSNe) due to their high peak luminosity and long light-curves. These hydrogen-free explosions (SLSNe-I) can be seen to z 4 and therefore, offer the possibility of probing the distant Universe. Aims: We aim to investigate the possibility of detecting SLSNe-I using ESA's Euclid satellite, scheduled for launch in 2020. In particular, we study the Euclid Deep Survey (EDS) which will provide a unique combination of area, depth and cadence over the mission. Methods: We estimated the redshift distribution of Euclid SLSNe-I using the latest information on their rates and spectral energy distribution, as well as known Euclid instrument and survey parameters, including the cadence and depth of the EDS. To estimate the uncertainties, we calculated their distribution with two different set-ups, namely optimistic and pessimistic, adopting different star formation densities and rates. We also applied a standardization method to the peak magnitudes to create a simulated Hubble diagram to explore possible cosmological constraints. Results: We show that Euclid should detect approximately 140 high-quality SLSNe-I to z 3.5 over the first five years of the mission (with an additional 70 if we lower our photometric classification criteria). This sample could revolutionize the study of SLSNe-I at z > 1 and open up their use as probes of star-formation rates, galaxy populations, the interstellar and intergalactic medium. In addition, a sample of such SLSNe-I could improve constraints on a time-dependent dark energy equation-of-state, namely w(a), when combined with local SLSNe-I and the expected SN Ia sample from the Dark Energy Survey. Conclusions: We show that Euclid will observe hundreds of SLSNe-I for free. These luminous transients will be in the Euclid data-stream and we should prepare now to identify them as they offer a new probe of the high-redshift Universe for both

  9. Ultra-Rapid UV Spectroscopy of an Interacting Supernova Discovered by K2

    Science.gov (United States)

    Foley, Ryan

    2017-08-01

    The supernova (SN) community is preparing for an extraordinary experiment. For 5 months, the Kepler telescope (K2) will perform a SN survey. Monitoring 20,000 galaxies with a 30-minute cadence, K2 will detect 50 SNe within hours - perhaps even minutes - of explosion. Such data have proven to be a unique window to the details of the SN explosion, progenitor, and circumstellar (CS) environment. We are devoting significant ground-based telescopic resources to search for and follow these SNe.We propose to take advantage of these emergent SNe and exquisite K2 light curves to study 1 SN in detail with HST. For the first few days after a SN explosion, one can potentially see signs of the SN interacting with its CS environment (e.g., a wind, accretion disk, companion star) that are not present later in its evolution. For instance, the large UV flux from a SN shock breakout will ionize CS gas. As the gas recombines over the following days, it produces excess broad-band flux and reveals the CSM (and thus progenitor) composition through emission lines. While early optical data can be illuminating, its utility is limited. However, UV spectra can greatly enhance our understanding of SN progenitor systems, including progenitor composition, CS environment, and the existence of a binary companion. Our program will observe a single K2 SN that shows signs of early interaction.Because of the ephemeral nature of the interaction signatures, this program requires an ultra-rapid ToO. The combination of K2 photometry, ground-based data, and HST UV spectra will be a completely unique and defining data set. As Kepler will soon be retired, this is our only opportunity for such a program.

  10. Observation of 23 Supernovae That Exploded <300 pc from Earth during the past 300 kyr

    Science.gov (United States)

    Firestone, R. B.

    2014-07-01

    Four supernovae (SNe), exploding recorded 44, 37, 32, and 22 kyr ago in the radiocarbon (14C) record during the past 50 kyr. Each SN left a nearly identical signature in the record, beginning with an initial sudden increase in atmospheric radiocarbon, when the SN exploded, followed by a hiatus of 1500 yr, and concluding with a sustained 2000 yr increase in global radiocarbon due to γ-rays produced by diffusive shock in the SN remnant (SNR). For the past 18 kyr excess radiocarbon has decayed with the 14C half-life. SN22kyrBP, is identified as the Vela SN that exploded 250 ± 30 pc from Earth. These SN are confirmed in the 10Be, 26Al, 36Cl, and NO_3^- geologic records. The rate of near-Earth SNe is consistent with the observed rate of historical SNe giving a galactic rate of 14 ± 3 kyr-1 assuming the Chandra Galactic Catalog SNR distribution. The Earth has been used as a calorimeter to determine that ≈2 × 1049 erg were released as γ-rays at the time of each SN explosion and ≈1050 erg in γ-rays following each SN. The background rate of 14C production by cosmic rays has been determined as 1.61 atoms cm-2 s-1. Approximately 1/3 of the cosmic ray energy produced by diffusive shock in the SNR was observed to be emitted as high-energy γ-rays. Analysis of the 10Be/9Be ratio in marine sediment identified 19 additional near-Earth SNe that exploded 50-300 kyr ago. Comparison of the radiocarbon record with global temperature variations indicated that each SN explosion is correlated with a concurrent global warming of ≈3°C-4°C.

  11. The supernova: A stellar spectacle

    Science.gov (United States)

    Straka, W. C.

    1976-01-01

    The life of a star, the supernova, related objects and their importance in astronomy and science in general are discussed. Written primarily for science teachers of secondary school chemistry, physics, and earth sciences, the booklet contains a glossary, reference sources, suggested topics for discussion, and projects for individual or group assignment.

  12. Photoactive energetic materials

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, David E.; Hanson, Susan Kloek; Scharff, Robert Jason; Veauthier, Jacqueline Marie; Myers, Thomas Winfield

    2018-02-27

    Energetic materials that are photoactive or believed to be photoactive may include a conventional explosive (e.g. PETN, nitroglycerine) derivatized with an energetic UV-absorbing and/or VIS-absorbing chromophore such as 1,2,4,5-tetrazine or 1,3,5-triazine. Absorption of laser light having a suitably chosen wavelength may result in photodissociation, decomposition, and explosive release of energy. These materials may be used as ligands to form complexes. Coordination compounds include such complexes with counterions. Some having the formula M(L).sub.n.sup.2+ were synthesized, wherein M is a transition metal and L is a ligand and n is 2 or 3. These may be photoactive upon exposure to a laser light beam having an appropriate wavelength of UV light, near-IR and/or visible light. Photoactive materials also include coordination compounds bearing non-energetic ligands; in this case, the counterion may be an oxidant such as perchlorate.

  13. The Host Galaxies of Type Ia Supernovae Discovered by the Palomar Transient Factory

    Science.gov (United States)

    Pan, Y.-C.; Sullivan, M.; McGuire, K.; Hook, I. M.; Nugent, P. E.; Howell, D. A.; Arcavi, I.; Botyanszki, J.; Cenko, Stephen Bradley; DeRose, J.

    2013-01-01

    We present spectroscopic observations of the host galaxies of 82 low-redshift type Ia supernovae (SNe Ia) discovered by the Palomar Transient Factory (PTF). We determine star-formation rates, gas-phase stellar metallicities, and stellar masses and ages of these objects. As expected, strong correlations between the SN Ia light-curve width (stretch) and the host age mass metallicity are found: fainter, faster-declining events tend to be hosted by older massive metal-rich galaxies. There is some evidence that redder SNe Ia explode in higher metallicity galaxies, but we found no relation between the SN colour and host galaxy extinction based on the Balmer decrement, suggesting that the colour variation of these SNe does not primarily arise from this source. SNe Ia in higher-mass metallicity galaxies also appear brighter after stretch colour corrections than their counterparts in lower mass hosts, and the stronger correlation is with gas-phase metallicity suggesting this may be the more important variable. We also compared the host stellar mass distribution to that in galaxy targeted SN surveys and the high-redshift untargeted Supernova Legacy Survey (SNLS). SNLS has many more low mass galaxies, while the targeted searches have fewer. This can be explained by an evolution in the galaxy stellar mass function, coupled with a SN delay-time distribution proportional to t1. Finally, we found no significant difference in the mass--metallicity relation of our SN Ia hosts compared to field galaxies, suggesting any metallicity effect on the SN Ia rate is small.

  14. Spatially Resolved MaNGA Observations of the Host Galaxy of Superluminous Supernova 2017egm

    Science.gov (United States)

    Chen, Ting-Wan; Schady, Patricia; Xiao, Lin; Eldridge, J. J.; Schweyer, Tassilo; Lee, Chien-Hsiu; Yu, Po-Chieh; Smartt, Stephen J.; Inserra, Cosimo

    2017-11-01

    Superluminous supernovae (SLSNe) are found predominantly in dwarf galaxies, indicating that their progenitors have a low metallicity. However, the most nearby SLSN to date, SN 2017egm, occurred in the spiral galaxy NGC 3191, which has a relatively high stellar mass and correspondingly high metallicity. In this Letter, we present detailed analysis of the nearby environment of SN 2017egm using MaNGA IFU data, which provides spectral data on kiloparsec scales. From the velocity map we find no evidence that SN 2017egm occurred within some intervening satellite galaxy, and at the SN position most metallicity diagnostics yield a solar and above solar metallicity (12+{log}({{O}}/{{H}})˜ 8.8{--}9.1). Additionally, we measure a small Hα equivalent width (EW) at the SN position of just 34 Å, which is one of the lowest EWs measured at any SLSN or gamma-ray burst position, and indicative of the progenitor star being comparatively old. We also compare the observed properties of NGC 3191 with other SLSN host galaxies. The solar-metallicity environment at the position of SN 2017egm presents a challenge to our theoretical understanding, and our spatially resolved spectral analysis provides further constraints on the progenitors of SLSNe.

  15. Properties and Alignment of Interstellar Dust Grains toward Type Ia Supernovae with Anomalous Polarization Curves

    Science.gov (United States)

    Hoang, Thiem

    2017-02-01

    Recent photometric and polarimetric observations of Type Ia supernovae (SNe Ia) show unusually low total-to-selective extinction ratios (R V data (SN 1986G, SN 2006X, SN 2008fp, and SN 2014J). We find that to reproduce low values of R V , a significant enhancement in the mass of small grains of radius a data are attributed to IS dust (model 1), but a good fit is obtained when accounting for the contribution of CS dust (model 2). For SN 2008fp, our best-fit results for model 1 show that in order to reproduce an extreme value of λ max ˜ 0.15 μm, small silicate grains must be aligned as efficiently as big grains. For this case, we suggest that strong radiation from the SN can induce efficient alignment of small grains in a nearby intervening molecular cloud via the radiative torque (RAT) mechanism. The resulting time dependence polarization from this RAT alignment model can be tested by observing at ultraviolet wavelengths.

  16. THE DISCOVERY OF THE MOST DISTANT KNOWN TYPE Ia SUPERNOVA AT REDSHIFT 1.914

    Energy Technology Data Exchange (ETDEWEB)

    Jones, David O.; Rodney, Steven A.; Riess, Adam G. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Mobasher, Bahram [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Dahlen, Tomas; Casertano, Stefano; Koekemoer, Anton [Space Telescope Science Institute, Baltimore, MD 21218 (United States); McCully, Curtis; Keeton, Charles R.; Patel, Brandon [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); Frederiksen, Teddy F.; Hjorth, Jens [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Strolger, Louis-Gregory [Department of Physics, Western Kentucky University, Bowling Green, KY 42101 (United States); Wiklind, Tommy G. [Joint ALMA Observatory, ESO, Santiago (Chile); Challis, Peter [Harvard/Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Graur, Or [School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Hayden, Brian; Garnavich, Peter [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Weiner, Benjamin J. [Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); and others

    2013-05-10

    We present the discovery of a Type Ia supernova (SN) at redshift z = 1.914 from the CANDELS multi-cycle treasury program on the Hubble Space Telescope (HST). This SN was discovered in the infrared using the Wide-Field Camera 3, and it is the highest-redshift Type Ia SN yet observed. We classify this object as a SN Ia by comparing its light curve and spectrum with those of a large sample of Type Ia and core-collapse SNe. Its apparent magnitude is consistent with that expected from the {Lambda}CDM concordance cosmology. We discuss the use of spectral evidence for classification of z > 1.5 SNe Ia using HST grism simulations, finding that spectral data alone can frequently rule out SNe II, but distinguishing between SNe Ia and SNe Ib/c can require prohibitively long exposures. In such cases, a quantitative analysis of the light curve may be necessary for classification. Our photometric and spectroscopic classification methods can aid the determination of SN rates and cosmological parameters from the full high-redshift CANDELS SN sample.

  17. INTENSE ENERGETIC GAS DISCHARGE

    Science.gov (United States)

    Luce, J.S.

    1960-03-01

    A method and apparatus for initiating and sustaining an energetic gas arc discharge are described. A hollow cathode and a hollow anode are provided. By regulating the rate of gas flow into the interior of the cathode, the arc discharge is caused to run from the inner surface of the cathode with the result that adequate space-charge neutralization is provided inside the cathode but not in the main arc volume. Thus, the gas fed to the cathode is substantially completely ionized before it leaves the cathode, with the result that an energetic arc discharge can be maintained at lower operating pressures.

  18. The Korean 1592-1593 Record of a Guest Star: An 'Impostor' of the Cassiopeia A Supernova?

    Science.gov (United States)

    Park, Changbom; Yoon, Sung-Chul; Koo, Bon-Chul

    2016-12-01

    The missing historical record of the Cassiopeia A (Cas A) supernova (SN) event implies a large extinction to the SN, possibly greater than the interstellar extinction to the current SN remnant. Here we investigate the possibility that the guest star that appeared near Cas A in 1592-1593 in Korean history books could have been an `impostor' of the Cas A SN, i.e., a luminous transient that appeared to be a SN but did not destroy the progenitor star, with strong mass loss to have provided extra circumstellar extinction. We first review the Korean records and show that a spatial coincidence between the guest star and Cas A cannot be ruled out, as opposed to previous studies. Based on modern astrophysical findings on core-collapse SN, we argue that Cas A could have had an impostor and derive its anticipated properties. It turned out that the Cas A SN impostor must have been bright (M_V =-14.7 ± 2.2 mag) and an amount of dust with visual extinction of ≥ 2.8± 2.2 mag should have formed in the ejected envelope and/or in a strong wind afterwards. The mass loss needs to have been spherically asymmetric in order to see the light echo from the SN event but not the one from the impostor event.

  19. The Data Release of the Sloan Digital Sky Survey-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Sako, Masao; et al.

    2014-01-14

    This paper describes the data release of the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey conducted between 2005 and 2007. Light curves, spectra, classifications, and ancillary data are presented for 10,258 variable and transient sources discovered through repeat ugriz imaging of SDSS Stripe 82, a 300 deg2 area along the celestial equator. This data release is comprised of all transient sources brighter than r~22.5 mag with no history of variability prior to 2004. Dedicated spectroscopic observations were performed on a subset of 889 transients, as well as spectra for thousands of transient host galaxies using the SDSS-III BOSS spectrographs. Photometric classifications are provided for the candidates with good multi-color light curves that were not observed spectroscopically. From these observations, 4607 transients are either spectroscopically confirmed, or likely to be, supernovae, making this the largest sample of supernova candidates ever compiled. We present a new method for SN host-galaxy identification and derive host-galaxy properties including stellar masses, star-formation rates, and the average stellar population ages from our SDSS multi-band photometry. We derive SALT2 distance moduli for a total of 1443 SN Ia with spectroscopic redshifts as well as photometric redshifts for a further 677 purely-photometric SN Ia candidates. Using the spectroscopically confirmed subset of the three-year SDSS-II SN Ia sample and assuming a flat Lambda-CDM cosmology, we determine Omega_M = 0.315 +/- 0.093 (statistical error only) and detect a non-zero cosmological constant at 5.7 sigmas.

  20. Imaging the Chemical Distribution in Type Ia SN Ejecta

    Science.gov (United States)

    Fesen, Robert

    2004-07-01

    We know Type Ia supernovae are thermonuclear explosions of CO white dwarfs, but we don't know the specifics of how the nuclear burning process proceeds from the core outward once it starts. The thermonuclear instability is thought to start off as a subsonic, turbulent deflagration or burning wave but then, at some point, may transition into a blast or detonation wave. In such "delayed detonation" models, differences between normal and subluminous Type Ia SNe reflect differences in the amount of burning that has occurred in the pre-detonation phase. More burning helps to pre-expand the WD before passage of the detontation wave, which then results in different final element abundances and internal Fe-rich ejecta structure. Directly imaging the 2-D chemical distribution of ejecta from a Type Ia SN is actually possible in the case of the subluminous Type Ia SN 1885, which occurred on the near-side of M31's central bulge. This 119 year old remnant is visible -- from its core to its outer edge -- via strong optical/UV Ca and Fe line absorptions. Remarkably, the SNR appears to still be in a nearly free expansion phase, meaning that the elemental stratification seen present today accurately reflects SN Ia explosive nucleosynthesis physics. We propose to obtain ACS WFC/HRC images of SN 1885 in order to take advantage of this extraordinary situation: Having a young, nearby Type Ia SN remnant visible in silhouette against a galaxy-size light table. These unique observations will reveal a SN Ia's Ca and Fe ejecta distribution, density structure, sphericity, and ionization state as a function of expansion velocity, thereby confronting various SN Ia models with detailed ejecta stratification and expansion velocity maps.

  1. MASTER-SAAO: contradictory SN and flaring OT

    Science.gov (United States)

    Balanutsa, P.; Lipunov, V.; Buckley, D.; Gorbovskoy, E.; Tiurina, N.; Kuznetsov, A.; Kornilov, V.; Gress, O.; Pogrosheva, T.; Shumkov, V.; Vladimirov, V.; Vlasenko, D.; Kuvshinov, D.; Gabovich, A.

    2017-07-01

    MASTER-SAAO auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 30L ) discovered OT source at (RA, Dec) = 03h 42m 50.70s , -01d 52m 28s.7 on 2017-07-01.1753UT with unfiltered (6 images), that contradicts to Ia type detected in ATEL #10240 , ATEL #10225 for ATLAS17dcl ( http://www.supernova.thistlethwaites.com/sn2017/sndate.html ). It is in 8.4"W,20"S of PGC135685 with Btc=15.13, Vgsr=2773 http://leda.univ-lyon1.fr/ledacat.cgi?PGC135685 Spectral observations are required.

  2. Statistical Analysis of Supernova Remnants in the Large Magellanic Cloud

    Science.gov (United States)

    Bozzetto, Luke M.; Filipović, Miroslav D.; Vukotić, Branislav; Pavlović, Marko Z.; Urošević, Dejan; Kavanagh, Patrick J.; Arbutina, Bojan; Maggi, Pierre; Sasaki, Manami; Haberl, Frank; Crawford, Evan J.; Roper, Quentin; Grieve, Kevin; Points, S. D.

    2017-05-01

    We construct the most complete sample of supernova remnants (SNRs) in any galaxy—the Large Magellanic Cloud (LMC) SNR sample. We study their various properties such as spectral index (α), size, and surface brightness. We suggest an association between the spatial distribution and environment density of LMC SNRs, and their tendency to be located around supergiant shells. We find evidence that the 16 known type Ia LMC SNRs are expanding in a lower density environment compared to the Core-Collapse (CC) type. The mean diameter of our entire population (74) is 41 pc, which is comparable to nearby galaxies. We did not find any correlation between the type of SN explosion, ovality, or age. The N(residency time of electrons in the galaxy (4.0-14.3 Myr), implying that SNRs should be the dominant mechanism for the production and acceleration of CRs.

  3. Solar, supernova, atmospheric and geo neutrino studies using JUNO detector

    CERN Document Server

    Guo, Wan-lei; Li, Yufeng; Salamanna, Giuseppe

    2016-01-01

    Aside from its primary purpose of shedding light on the mass hierarchy (MH) using reactor anti-neutrinos, the JUNO experiment in Jiangmen (China) will also contribute to study neutrinos from non-reactor sources. In this poster we review JUNO's goals in the realms of supernova, atmospheric, solar and geo-neutrinos; present the related experimental issues and provide the current estimates of its potential. For a typical galactic SN at a distance of 10 kpc, JUNO will record about 5000 events from inverse beta decay, 2000 events from elastic neutrino-proton scattering, 300 events from neutrino-electron scattering, and the charged current and neutral current interactions on the ${^{12}}{\\rm C}$ nuclei. For atmospheric neutrinos, JUNO should be able to detect $\

  4. The Height Distribution of Core Collapse Supernovae in Disk Galaxies

    Science.gov (United States)

    Molloy, M.; Meurs, E.; Norci, L.; Kavanagh, P.

    Core collapse (CC) supernovae are exploding massive stars and are therefore expected to occur in the disks of spiral galaxies. However, in the historical record some CC SNae can be noticed outside the disks. To investigate this further, the distribution of SNae above and below the disks of spiral galaxies is examined for the case of edge-on galaxies. The CC SNae that are observed away from their parent Population I in the galaxy planes must previously have left the disks due to dynamical encounters or SN explosions of companion stars. We develop a simple interpretative model that describes the observed height distribution of the SNae, taking into account kick velocities imparted during the explosive events. We also briefly comment on the radial distribution of SNae, utilizing face-on galaxies for this purpose.

  5. The population of supernova remnants in the Magellanic Clouds

    CERN Document Server

    Dennefeld, M

    1978-01-01

    The detection of SNRs in the Magellanic Clouds is reviewed with emphasis on its limits. A sample of SNRs is then used to derive the mean interval between SN explosions, tau . After the maximum constraints have been put on all the other parameters, the distribution of diameters of remnants with diameter less than 30 pc in the LMC is shown to agree well with theoretical predictions. In adopting a mean value of E/sub 0//n/sub 0/ (energy at explosion over surrounding density) of 5*10/sup 51/ ergs cm/sup 3/, the best value of tau is 300+or-100 years in good agreement with predictions from statistics of supernovae in external galaxies. The small number of remnants in the SMC prevents a similar approach being used with any statistical significance. (20 refs).

  6. Nanostructured Energetic Materials

    Science.gov (United States)

    2006-11-01

    Microencapsulation of energetic nanoparticles Microencapsulated Nanoparticles granules Microencapsulated granulesNanoparticles Encapsulation MIC MATERIAL...PRESSURE MEASUREMENTS IN MILLIMETER SCALE CELL Experimental Setup MIC Material Powder Loaded into MilliCell Hot Wire for Powder Initiation MIC Powder...Loaded into MilliCell Pressure Sensor Pressure measurements on lexane millicell 20mg of each material. Volume of the cell 30 cubic mm. HMT

  7. High-Redshift Type Ia Supernova Rates in Galaxy Cluster and Field Environments

    Science.gov (United States)

    Barbary, Kyle Harris

    This thesis presents Type Ia supernova (SN Ia) rates from the Hubble Space Telescope (HST) Cluster Supernova Survey, a program designed to efficiently detect and observe high-redshift supernovae by targeting massive galaxy clusters at redshifts 0.9 z z > 0.9 SNe. The SN Ia rate is found to be 0.50+0.23-0.19 (stat) +0.10-0.09 (sys) h 702 SNuB (SNuB = 10-12 SNe Lsun,B-1 yr-1), or in units of stellar mass, 0.36+0.16-0.13 (stat) +0.07-0.06 (sys) h 702 SNuM (SNuM = 10-12 SNe M sun-1 yr-1). This represents a factor of approximately 5 +/- 2 increase over measurements of the cluster rate at z influence of younger stellar populations the rate is also calculated specifically in cluster red-sequence galaxies and in morphologically early-type galaxies, with results similar to the full cluster rate. Finally, the upper limit of one host-less cluster SN Ia detected in the survey implies that the fraction of stars in the intra-cluster medium is less than 0.47 (95% confidence), consistent with measurements at lower redshifts. The volumetric SN Ia rate can also be used to constrain the SN Ia delay time distribution. However, there have been discrepancies in recent analyses of both the high-redshift rate and its implications for the delay time distribution. Here, the volumetric SN Ia rate out to z ˜ 1.6 is measured, based on ˜12 SNe Ia in the foregrounds and backgrounds of the clusters targeted in the survey. The rate is measured in four broad redshift bins. The results are consistent with previous measurements at z > 1 and strengthen the case for a SN Ia rate that is greater than approximately 0.6 x 10-4 h70 3 yr-1 Mpc-3 at z ˜ 1 and flattening out at higher redshift. Assumptions about host-galaxy dust extinction used in different high-redshift rate measurements are examined. Different assumptions may account for some of the difference in published results for the z ˜ 1 rate.

  8. Employing modern statistics to explore the universe with Type Ia supernovae

    Science.gov (United States)

    Weyant, Anja

    The Large Synoptic Survey Telescope (LSST) anticipates observing hundreds of thousands of well-measured Type Ia supernovae (SNe Ia). These stellar remnant explosions are exceptional in that they have a standardizeable light curve which allows for an accurate measurement of their luminosity. The standard nature of SNe Ia allow us to measure relative distances in the Universe with better than 6% precision in distance. With distance estimates in hand to large sets of galaxies through Type Ia Supernova (SN Ia) measurements, we can measure the expansion history of the Universe or create flow models of how galaxies (matter) near the Milky Way are moving. In this new regime of large datasets, weaknesses and limitations of the current techniques for estimating cosmological parameters and modeling local flows are becoming apparent. As statistical errors are reduced systematic uncertainties ranging from calibration to survey design and cadence to host galaxy contamination are dominating the error budget and limiting our ability to make improvements on cosmological measurements. Similarly, recent comparisons of flow models reveal systematic inconsistencies between different approaches. For my dissertation I have employed modern statistical methods to improve flow models in the local Universe by accounting for the non-uniform distribution of data across the sky and demonstrated how Approximate Bayesian Computation can tackle complicated likelihood functions in supernova cosmology. I also present the first results of a new near-infrared SN Ia survey called "SweetSpot" whose focus is on improving our ability to standardize the total luminosity of SNe Ia.

  9. Modeling the binary circumstellar medium of Type IIb/L/n supernova progenitors

    Science.gov (United States)

    Kolb, Christopher; Blondin, John; Borkowski, Kazik; Reynolds, Stephen

    2018-01-01

    Circumstellar interaction in close binary systems can produce a highly asymmetric environment, particularly for systems with a mass outflow velocity comparable to the binary orbital speed. This asymmetric circumstellar medium (CSM) becomes visible after a supernova explosion, when SN radiation illuminates the gas and when SN ejecta collide with the CSM. We aim to better understand the development of this asymmetric CSM, particularly for binary systems containing a red supergiant progenitor, and to study its impact on supernova morphology. To achieve this, we model the asymmetric wind and subsequent supernova explosion in full 3D hydrodynamics using the shock-capturing hydro code VH-1 on a spherical yin-yang grid. Wind interaction is computed in a frame co-rotating with the binary system, and gas is accelerated using a radiation pressure-driven wind model where optical depth of the radiative force is dependent on azimuthally-averaged gas density. We present characterization of our asymmetric wind density distribution model by fitting a polar-to-equatorial density contrast function to free parameters such as binary separation distance, primary mass loss rate, and binary mass ratio.

  10. Near-Infrared Spectroscopic Evolution of Type Ia & Stripped-Envelope Supernovae

    Science.gov (United States)

    Gerardy, Christopher L.; Wheeler, J. Craig; Hoflich, Peter; Howie Marion, G.; Nomoto, Ken'ichi; Fesen, Robert A.; Wang, Lifan

    2003-02-01

    Near-infrared (NIR) spectroscopy is a powerful tool for the study of supernovae (SNe), offering valuable insights into heavy element nucleosynthesis, explosion physics, and pre-explosion mass loss and evolution. Observations of the early-time NIR spectroscopic evolution of Type Ia and Type Ib/Ic SNe will provide constraints on the chemical structure of SN ejecta and the explosion kinematics of supernovae which cannot be obtained in other wavelength regimes. In addition, late-time NIR spectra will be used to measure the radioactive heavy-element yield in these SNe and also probe for molecule formation in the SN ejecta. Here we propose a KPNO ``Target-of-Opportunity'' (ToO) program to obtain early-time NIR spectra of a bright Type Ia or Type Ib/Ic supernova (FLAMINGOS when it is available on either the 2.1 or 4 m telescopes. We are requesting five visits of 1-2 hrs (including calibrations) at roughly 1 week intervals, covering the evolution from discovery to about 30 days after maximum light. We also request a four night run on the 4 m telescope near the end of FLAMINGOS availability in May to obtain a high-quality late-time spectrum of the ToO target.

  11. Type Ia Supernova Hubble Residuals and Host-Galaxy Properties

    Energy Technology Data Exchange (ETDEWEB)

    Nearby Supernova Factory; Kim, A. G.; Aldering, G.; Antilogus, P.; Aragon, C.; Bailey, S.; Baltay, C.; Bongard, S.; Buton, C.; Canto, A.; Cellier-Holzem, F.; Childress, M.; Chotard, N.; Copin, Y.; Fakhouri, H. K.; Feindt, U.; Fleury, M.; Gangler, E.; Greskovic, P.; Guy, J.; Kowalski, M.; Lombardo, S.; Nordin, J.; Nugent, P.; Pain, R.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigault, M.; Runge, K.; Saunders, C.; Scalzo, R.; Smadja, G.; Tao, C.; Thomas, R. C.; Weaver, B. A.

    2014-01-17

    Kim et al. (2013) [K13] introduced a new methodology for determining peak- brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spec- trophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is 0.013 ? 0.031 mag for a supernova subsample with data coverage corresponding to the K13 training; at ? 1?, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement the Hubble residual step with host mass is 0.045 ? 0.026 mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch param- eters: Steps at> 2? significance are found in SALT2 Hubble residuals in samples split by the values of their K13 x(1) and x(2) light-curve parameters. x(1) affects the light- curve width and color around peak (similar to the∆m15 and stretch parameters), and x(2) affects colors, the near-UV light-curve width, and the light-curve decline 20 to 30 days after peak brightness. The novel light-curve analysis, increased parameter set, and magnitude corrections of K13 may be capturing features of SN Ia diversity arising from progenitor stellar evolution.

  12. Type Ia supernova Hubble residuals and host-galaxy properties

    Energy Technology Data Exchange (ETDEWEB)

    Kim, A. G.; Aldering, G.; Aragon, C.; Bailey, S.; 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.; Fleury, M.; Guy, J. [Laboratoire de Physique Nucléaire et des Hautes Énergies, Université Pierre et Marie Curie Paris 6, Université Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Feindt, U.; Greskovic, P.; Kowalski, M. [Physikalisches Institut, Universität Bonn, Nußallee 12, D-53115 Bonn (Germany); Childress, M. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Chotard, N.; Copin, Y.; Gangler, E. [Université de Lyon, F-69622 Lyon (France); Université de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucléaire de Lyon (France); and others

    2014-03-20

    Kim et al. introduced a new methodology for determining peak-brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spectrophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is 0.013 ± 0.031 mag for a supernova subsample with data coverage corresponding to the K13 training; at <<1σ, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement of the Hubble residual step with the host mass is 0.045 ± 0.026 mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch parameters: steps at >2σ significance are found in SALT2 Hubble residuals in samples split by the values of their K13 x(1) and x(2) light-curve parameters. x(1) affects the light-curve width and color around peak (similar to the Δm {sub 15} and stretch parameters), and x(2) affects colors, the near-UV light-curve width, and the light-curve decline 20-30 days after peak brightness. The novel light-curve analysis, increased parameter set, and magnitude corrections of K13 may be capturing features of SN Ia diversity arising from progenitor stellar evolution.

  13. SN 2011hs

    DEFF Research Database (Denmark)

    Bufano, F.; Pignata, G.; Bersten, M.

    2014-01-01

    Observations spanning a large wavelength range, from X-ray to radio, of the Type IIb supernova 2011hs are presented, covering its evolution during the first year after explosion. The optical light curve presents a narrower shape and a fainter luminosity at peak than previously observed for Type I...

  14. Effects of Dimensionality on Pair-Instability Supernova Explosions

    Science.gov (United States)

    Gilmer, Matthew S.; Kozyreva, Alexandra; Hirschi, Raphael; Fröhlich, Carla

    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 the explosion phase in 1D, 2D, and 3D. We find that the ejecta from the multidimensional simulations have slightly shallower abundance gradients due to mixing at shell boundaries. We compute synthetic LCs whose shapes show no discernible differences due to the multidimensional effects.

  15. No hot and luminous progenitor for Tycho's supernova

    Science.gov (United States)

    Woods, T. E.; Ghavamian, P.; Badenes, C.; Gilfanov, M.

    2017-11-01

    Type Ia supernovae have proven vital to our understanding of cosmology, both as standard candles and for their role in galactic chemical evolution; however, their origin remains uncertain. The canonical accretion model implies a hot and luminous progenitor that would ionize the surrounding gas out to a radius of 10-100 pc for 100,000 years after the explosion. Here, we report stringent upper limits on the temperature and luminosity of the progenitor of Tycho's supernova (SN 1572), determined using the remnant itself as a probe of its environment. Hot, luminous progenitors that would have produced a greater hydrogen ionization fraction than that measured at the radius of the present remnant ( 3 pc) can thus be excluded. This conclusively rules out steadily nuclear-burning white dwarfs (supersoft X-ray sources), as well as disk emission from a Chandrasekhar-mass white dwarf accreting approximately greater than 10-8 M⊙ yr-1 (recurrent novae; M⊙ is equal to one solar mass). The lack of a surrounding Strömgren sphere is consistent with the merger of a double white dwarf binary, although other more exotic scenarios may be possible.

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

    National Research Council Canada - National Science Library

    Stritzinger, Maximilian D; Phillips, M. M; Boldt, Luis N; Burns, Chris; Campillay, Abdo; Contreras, Carlos; Gonzalez, Sergio; Folatelli, Gastón; Morrell, Nidia; Krzeminski, Wojtek; Roth, Miguel; Salgado, Francisco; DePoy, D. L; Hamuy, Mario; Freedman, Wendy L; Madore, Barry F; Marshall, J. L; Persson, Sven E; Rheault, Jean-Philippe; Suntzeff, Nicholas B; Villanueva, Steven; Li, Weidong; Filippenko, Alexei V

    2011-01-01

    The Carnegie Supernova Project (CSP) was a five-year observational survey conducted at Las Campanas Observatory that obtained, among other things, high-quality light curves of similar to 100 low-redshift Type Ia supernovae (SNe Ia...

  17. Improvements to type Ia supernova models

    Science.gov (United States)

    Saunders, Clare M.

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

  18. A population of highly energetic transient events in the centres of active galaxies

    Science.gov (United States)

    Kankare, E.; Kotak, R.; Mattila, S.; Lundqvist, P.; Ward, M. J.; Fraser, M.; Lawrence, A.; Smartt, S. J.; Meikle, W. P. S.; Bruce, A.; Harmanen, J.; Hutton, S. J.; Inserra, C.; Kangas, T.; Pastorello, A.; Reynolds, T.; Romero-Cañizales, C.; Smith, K. W.; Valenti, S.; Chambers, K. C.; Hodapp, K. W.; Huber, M. E.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.

    2017-12-01

    Recent all-sky surveys have led to the discovery of new types of transients. These include stars disrupted by the central supermassive black hole, and supernovae that are 10-100 times more energetic than typical ones. However, the nature of even more energetic transients that apparently occur in the innermost regions of their host galaxies is hotly debated1-3. Here we report the discovery of the most energetic of these to date: PS1-10adi, with a total radiated energy of 2.3 × 1052 erg. The slow evolution of its light curve and persistently narrow spectral lines over ˜ 3 yr are inconsistent with known types of recurring black hole variability. The observed properties imply powering by shock interaction between expanding material and large quantities of surrounding dense matter. Plausible sources of this expanding material are a star that has been tidally disrupted by the central black hole, or a supernova. Both could satisfy the energy budget. For the former, we would be forced to invoke a new and hitherto unseen variant of a tidally disrupted star, while a supernova origin relies principally on environmental effects resulting from its nuclear location. Remarkably, we also discover that PS1-10adi is not an isolated case. We therefore surmise that this new population of transients has previously been overlooked due to incorrect association with underlying central black hole activity.

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

    OpenAIRE

    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 gravi...

  20. Properties and Alignment of Interstellar Dust Grains toward Type Ia Supernovae with Anomalous Polarization Curves

    Energy Technology Data Exchange (ETDEWEB)

    Hoang, Thiem, E-mail: thiemhoang@kasi.re.kr [Korea Astronomy and Space Science Institute 776, Daedeokdae-ro, Yuseong-gu, Daejeon 34055 (Korea, Republic of); Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Institute of Theoretical Physics, Goethe Universität Frankfurt, D-60438 Frankfurt am Main (Germany)

    2017-02-10

    Recent photometric and polarimetric observations of Type Ia supernovae (SNe Ia) show unusually low total-to-selective extinction ratios ( R {sub V} < 2) and wavelengths of maximum polarization ( λ{sub max} < 0.4 μ m) for several SNe Ia, which indicates peculiar properties of interstellar (IS) dust in the SN-hosted galaxies and/or the presence of circumstellar (CS) dust. In this paper, we use an inversion technique to infer the best-fit grain size distribution and the alignment function of interstellar grains along the lines of sight toward four SNe Ia with anomalous extinction and polarization data (SN 1986G, SN 2006X, SN 2008fp, and SN 2014J). We find that to reproduce low values of R{sub V}, a significant enhancement in the mass of small grains of radius a < 0.1 μ m is required. For SN 2014J, a simultaneous fit to its observed extinction and polarization is unsuccessful if all the data are attributed to IS dust (model 1), but a good fit is obtained when accounting for the contribution of CS dust (model 2). For SN 2008fp, our best-fit results for model 1 show that in order to reproduce an extreme value of λ{sub max} ∼ 0.15 μ m, small silicate grains must be aligned as efficiently as big grains. For this case, we suggest that strong radiation from the SN can induce efficient alignment of small grains in a nearby intervening molecular cloud via the radiative torque (RAT) mechanism. The resulting time dependence polarization from this RAT alignment model can be tested by observing at ultraviolet wavelengths.

  1. Life after stellar death: Planetary Nebulae and Supernova Remnants

    Science.gov (United States)

    Boumis, P.

    2013-09-01

    Planetary nebulae (PNe) are powerful tracers of our Galaxy's star formation history. Their study can provide insight to the late stages of stellar evolution, the nucleosynthesis in low and intermediate mass stars (1-8Mo) and the chemical evolution of galaxies. Supernova explosions belong to the most spectacular events in the Universe. Supernova remnants (SNRs), which are the consequent results of these events and come from the late stages of massive stars (>8Mo), are among the strongest radio sources observed. They have a major influence on both the properties of the interstellar medium (ISM) and the evolution of galaxies as a whole. They enrich the ISM with heavy elements, release about 1051 ergs of energy, heat the ISM, compress the magnetic field, and efficiently accelerate, by their shock waves, energetic cosmic rays observed throughout the Galaxy. I will present results of our work on PNe and SNRs, which aims to (a) discover optical SNRs in the Galaxy, (b) study their morphology and kinematics, (c) characterize their properties (such as density, shock velocity etc.) and (d) provide information on their interaction with the ISM, using the "Aristarchos" among other telescopes.

  2. A Deep Search with HST for Late Time Supernova Signatures in the Hosts of XRF 011030 and XRF 020427

    Science.gov (United States)

    Patel, Sandeep; Kouveliotou, Chryssa; Levan, Andrew; Fruchter, Andrew; Rol, Evert; Rhoads, James; Gorosabel, Javier; Ramirez-Ruiz, Enrico; Hjorth, Jens; Wijers, Ralph

    2004-01-01

    X-ray Flashes (XRFs), are, like Gamma-Ray Bursts (GRBs) thought to signal the collapse of massive stars in distant galaxies. Many models posit that the isotropic equivalent energies of XRFs are lower than those for GRBs, such that they are visible hom a reduced range of distances when compared with GRBs. Here we present the results of two epoch Hubble Space Telescope imaging of two XRFs. These images taken approximately 45 and 200 days post bust reveal no evidence for an associated supernova in either case. Supernovae such as SN 1998bw would have been visible out to z approximately 1.5 in each case, while faint supernovae such as SN 2002ap would be visible to z approximately 1. At these distances the bursts would not fit the observed correlations between E(sub p) and E(sub iso) and would have required extremely luminous X-ray afterglows. We conclude that should these XRFs reside at low redshift, it is necessary either that their line of sight is heavily extinguished, or that XRFs, unlike GRBs do not have temporally coincident supernovae.

  3. Bolometric Luminosities of Peculiar Type II-P Supernovae: Observational and Theoretical Approaches

    Science.gov (United States)

    Lusk, Jeremy Alexander

    2018-01-01

    In the three decades since the explosion of SN 1987A, only a handful of other supernovae have been detected which are also thought to originate from blue supergiant progenitors. In this study, we use the five best observed of these supernovae (SNe 1998A, 2000cb, 2006V, 2006au, and 2009E) to examine the bolometric properties of the class through observations and theoretical models. Several techniques for taking photometric observations and inferring bolometric luminosities have been used in the literature. Our newly-improved python package SuperBoL implements many of these techniques. The challenge remains that the true bolometric luminosity of the supernova cannot be directly observed. We must turn to theoretical models in order to examine the validity of the different observationally-based techniques. In this work, we make use of the NLTE generalized atmosphere code PHOENIX to produce synthetic spectra of known luminosity which match the observed supernova spectra. Synthetic photometry of these models is then used as input to SuperBoL to test the different observationally-based bolometric luminosity techniques.

  4. Detonating Failed Deflagration Model of Thermonuclear Supernovae. II. Comparison to Observations

    Science.gov (United States)

    Kasen, Daniel; Plewa, Tomasz

    2007-06-01

    We develop and demonstrate the methodology of testing multidimensional supernova models against observations by studying the properties of one example of the detonation from failed deflagration (DFD) explosion model of thermonuclear supernovae. Using time-dependent multidimensional radiative transfer calculations, we generate the synthetic broadband optical light curves, near-infrared light curves, color evolution curves, full spectral time series, and spectropolarization of the model, as seen from various viewing angles. All model observables are critically evaluated against examples of well-observed, standard Type Ia supernovae (SNe Ia). We explore the consequences of the intrinsic model asphericity by studying the dependence of the model emission on viewing angle, and by quantifying the resulting dispersion in (and internal correlations between) various model observables. These statistical properties of the model are also evaluated against those of the available observational sample of SNe Ia. On the whole, the DFD model shows good agreement with a broad range of SN Ia observations. Certain deficiencies are also apparent, and point to further developments within the basic theoretical framework. We also identify several intriguing orientation effects in the model that suggest ways in which the asphericity of SNe Ia may contribute to their photometric and spectroscopic diversity and, conversely, how the relative homogeneity of SNe Ia constrains the degree of asymmetry allowable in the models. The comprehensive methodology adopted in this work proves an essential component of developing and validating theoretical supernova models, and helps motivate and clearly define future directions in both the modeling and the observation of SNe Ia.

  5. Convection in Type 2 supernovae

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-10-15

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

  6. Antiprotons Produced in Supernova Remnants

    OpenAIRE

    Berezhko, E. G.; Ksenofontov, L. T.

    2014-01-01

    We present the energy spectrum of antiproton cosmic ray (CR) component calculated on the basis of the nonlinear kinetic model of CR production in supernova remnants (SNR). The model includes reacceleration of already existing in interstellar medium antiprotons as well as creation of antiprotons in nuclear collisions of accelerated protons with gas nuclei and their subsequent acceleration by SNR shock. It is shown that antiprotons production in SNRs produces considerable effect in their result...

  7. The Fermi Gamma-Ray Space Telescope discovers the pulsar in the young galactic supernova remnant CTA 1.

    Science.gov (United States)

    Abdo, A A; Ackermann, M; Atwood, W B; Baldini, L; Ballet, J; Barbiellini, G; Baring, M G; Bastieri, D; Baughman, B M; Bechtol, K; Bellazzini, R; Berenji, B; Blandford, R D; Bloom, E D; Bogaert, G; Bonamente, E; Borgland, A W; Bregeon, J; Brez, A; Brigida, M; Bruel, P; Burnett, T H; Caliandro, G A; Cameron, R A; Caraveo, P A; Carlson, P; Casandjian, J M; Cecchi, C; Charles, E; Chekhtman, A; Cheung, C C; Chiang, J; Ciprini, S; Claus, R; Cohen-Tanugi, J; Cominsky, L R; Conrad, J; Cutini, S; Davis, D S; Dermer, C D; de Angelis, A; de Palma, F; Digel, S W; Dormody, M; do Couto E Silva, E; Drell, P S; Dubois, R; Dumora, D; Edmonds, Y; Farnier, C; Focke, W B; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Gehrels, N; Germani, S; Giebels, B; Giglietto, N; Giordano, F; Glanzman, T; Godfrey, G; Grenier, I A; Grondin, M-H; Grove, J E; Guillemot, L; Guiriec, S; Harding, A K; Hartman, R C; Hays, E; Hughes, R E; Jóhannesson, G; Johnson, A S; Johnson, R P; Johnson, T J; Johnson, W N; Kamae, T; Kanai, Y; Kanbach, G; Katagiri, H; Kawai, N; Kerr, M; Kishishita, T; Kiziltan, B; Knödlseder, J; Kocian, M L; Komin, N; Kuehn, F; Kuss, M; Latronico, L; Lemoine-Goumard, M; Longo, F; Lonjou, V; Loparco, F; Lott, B; Lovellette, M N; Lubrano, P; Makeev, A; Marelli, M; Mazziotta, M N; McEnery, J E; McGlynn, S; Meurer, C; Michelson, P F; Mineo, T; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nakamori, T; Nolan, P L; Nuss, E; Ohno, M; Ohsugi, T; Okumura, A; Omodei, N; Orlando, E; Ormes, J F; Ozaki, M; Paneque, D; Panetta, J H; Parent, D; Pelassa, V; Pepe, M; Pesce-Rollins, M; Piano, G; Pieri, L; Piron, F; Porter, T A; Rainò, S; Rando, R; Ray, P S; Razzano, M; Reimer, A; Reimer, O; Reposeur, T; Ritz, S; Rochester, L S; Rodriguez, A Y; Romani, R W; Roth, M; Ryde, F; Sadrozinski, H F-W; Sanchez, D; Sander, A; Parkinson, P M Saz; Schalk, T L; Sellerholm, A; Sgrò, C; Siskind, E J; Smith, D A; Smith, P D; Spandre, G; Spinelli, P; Starck, J-L; Strickman, M S; Suson, D J; Tajima, H; Takahashi, H; Takahashi, T; Tanaka, T; Thayer, J B; Thayer, J G; Thompson, D J; Thorsett, S E; Tibaldo, L; Torres, D F; Tosti, G; Tramacere, A; Usher, T L; Van Etten, A; Vilchez, N; Vitale, V; Wang, P; Watters, K; Winer, B L; Wood, K S; Yasuda, H; Ylinen, T; Ziegler, M

    2008-11-21

    Energetic young pulsars and expanding blast waves [supernova remnants (SNRs)] are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a radio quiet pulsar located near the center of the compact synchrotron nebula inside the supernova remnant CTA 1. The pulsar, discovered through its gamma-ray pulsations, has a period of 316.86 milliseconds and a period derivative of 3.614 x 10(-13) seconds per second. Its characteristic age of 10(4) years is comparable to that estimated for the SNR. We speculate that most unidentified Galactic gamma-ray sources associated with star-forming regions and SNRs are such young pulsars.

  8. The first ten years of Swift supernovae

    Science.gov (United States)

    Brown, Peter J.; Roming, Peter W. A.; Milne, Peter A.

    2015-09-01

    The Swift Gamma Ray Burst Explorer has proven to be an incredible platform for studying the multiwavelength properties of supernova explosions. In its first ten years, Swift has observed over three hundred supernovae. The ultraviolet observations reveal a complex diversity of behavior across supernova types and classes. Even amongst the standard candle type Ia supernovae, ultraviolet observations reveal distinct groups. When the UVOT data is combined with higher redshift optical data, the relative populations of these groups appear to change with redshift. Among core-collapse supernovae, Swift discovered the shock breakout of two supernovae and the Swift data show a diversity in the cooling phase of the shock breakout of supernovae discovered from the ground and promptly followed up with Swift. Swift observations have resulted in an incredible dataset of UV and X-ray data for comparison with high-redshift supernova observations and theoretical models. Swift's supernova program has the potential to dramatically improve our understanding of stellar life and death as well as the history of our universe.

  9. The Korean 1592—1593 Record of a Guest Star: A Luminous Transient of the Cassiopeia A Supernova?

    Science.gov (United States)

    Koo, Bon-Chul; Park, Changbom; Yoon, Sung-Chul

    2017-01-01

    Cassiopeia A (Cas A) is one of the youngest supernova remnants (SNRs) in the Milky Way. It was discovered in 1940s as a bright radio source, and since then it has been extensively studied over all wavebands. In particular, the supernova (SN) flash light at the time of explosion was detected in 2008 as the SN light 'echo', which confirmed that Cas A is a remnant of core-collapse SN of Type IIb. It is relatively nearby, i.e., at 3.4 kpc, and the proper motion studies of almost freely-expanding SN material have yielded an accurate date of SN event, i.e., AD 1670—1680.The searches for historical observations of the Cas A SN event have found two suspicious records: Korean records on a 'guest star' that appeared near Cas A for three months in 1592-1593 and the record of the 6-th magnitude star '3 Cas' by John Flamsteed on August 16 in 1680. The former was ruled out because of ≥80 years of gap in the explosion date, while the Flamsteed’s 3 Cas is most likely a non-existing star resulting from combining measurements of two different stars by mistake. Therefore, there is no unambiguous historical record of this SN event occurred in the telescope era, which is puzzling.Here we investigate the possibility that the guest star in 1592—1593 in Korean history books could have been an 'impostor' of the Cas A SN, i.e., a luminous transient that appeared to be a SN but did not destroy the progenitor star, with strong mass loss to have provided extra circumstellar extinction to hide the SN event. We first review the Korean records and show that a spatial coincidence between the guest star and Cas A cannot be ruled out, as opposed to previous studies. We then argue that Cas A could have had an impostor and derive its anticipated properties. It turned out that the Cas A SN impostor must have been bright (MV=-14.7±2.2 mag) and an amount of dust with visual extinction of ≧2.8±2.2 mag should have formed in the ejected envelope and/or in a strong wind afterwards. The mass loss

  10. Nitroamino and Nitro Energetics

    Science.gov (United States)

    2012-09-13

    strongly recommend using 59 immediately after synthesis and avoiding storage. Based on our calculations using the Gaussian 03 (Revision D.01) suite...Azolylacetic acids give trinitromethyl-substituted compounds in one - pot reactions.220 5-Amino- l,2,4-triazolyl-5-acetic acid (49) was prepared by...Parrish, D. " Synthesis of an energetic nitrate ester ," Angew. Chem. Int. Ed., 2008, 47, 8307-8309; (d) Liu, W.-G.; Zybin, S. V.; Dasgupta, S.; Klapötke

  11. INTERSTELLAR SODIUM AND CALCIUM ABSORPTION TOWARD SN 2011dh IN M51

    Energy Technology Data Exchange (ETDEWEB)

    Ritchey, Adam M.; Wallerstein, George, E-mail: aritchey@astro.washington.edu, E-mail: wall@astro.washington.edu [Department of Astronomy, University of Washington, Seattle, WA 98195 (United States)

    2012-03-20

    We present high-resolution echelle observations of SN 2011dh, which exploded in the nearby, nearly face-on spiral galaxy M51. Our data, acquired on three nights when the supernova was near maximum brightness, reveal multiple absorption components in Na I D and Ca II H and K, which we identify with gaseous material in the Galactic disk or low halo and in the disk and halo of M51. The M51 components span a velocity range of over 140 km s{sup -1}, extending well beyond the range exhibited by H I 21 cm emission at the position of the supernova. Since none of the prominent Na I or Ca II components appear to coincide with the peak in H I emission, the supernova may lie just in front of the bulk of the H I disk. The Na I/Ca II ratios for the components with the most extreme positive and negative velocities relative to the disk are {approx}1.0, similar to those for more quiescent components, suggesting that the absorption originates in relatively cool gas. Production scenarios involving a galactic fountain and/or tidal interactions between M51 and its companion would be consistent with these results. The overall weakness of Na I D absorption in the direction of SN 2011dh confirms a low foreground and host galaxy extinction for the supernova.

  12. 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.

  13. ASASSN-17en: Discovery of A Probable Supernova in ESO 280-G 013

    Science.gov (United States)

    Brimacombe, J.; Brown, J. S.; Stanek, K. Z.; Holoien, T. W.-S.; Kochanek, C. S.; Shields, J.; Thompson, T. A.; Shappee, B. J.; Prieto, J. L.; Bersier, D.; Dong, Subo; Bose, S.; Chen, Ping; Bock, G.; Cruz, I.; Fernandez, J. M.; Post, R. S.; Stone, G.

    2017-04-01

    During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014), using data from the quadruple 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy ESO 280-G 013. ASASSN-17en (AT 2017cxy) was discovered in images obtained on UT 2017-04-08.31 at V 16.4 mag. We also detect the object in images obtained on UT 2017-04-11.24 (V 16.2), UT 2017-04-10.25 (V 16.3), UT 2017-04-09.40 (V 16.7), and UT 2017-04-04.38 (V 17.4).

  14. ASASSN-16of: Discovery of A Probable Supernova in ESO 087-IG 041

    Science.gov (United States)

    Kiyota, S.; Brown, J. S.; Stanek, K. Z.; Holoien, T. W.-S.; Kochanek, C. S.; Shields, J.; Shappee, B. J.; Prieto, J. L.; Bersier, D.; Dong, Subo; Bose, S.; Chen, Ping; Brimacombe, J.; Masi, G.; Post, R. S.; Stone, G.

    2016-12-01

    During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from the quadruple 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy ESO 087-IG 041. ASASSN-16of (AT 2016iqx) was discovered in images obtained on UT 2016-12-01.28 at V 16.7 mag. We also detect the object in images obtained on UT 2016-11-30.35 (V 16.8), UT 2016-11-28.28 (V 16.7), UT 2016-11-24.27 (V 17.0), UT 2016-11-22.23 (V 16.6), and UT 2016-11-19.34 (V 17.1).

  15. Photometric Identification of Population III Core-Collapse Supernovae: Multicolor Light Curve Simulations

    Science.gov (United States)

    Tolstov, Alexey; Nomoto, Ken'ichi; Tominaga, Nozomu; Ishigaki, Miho N.; Blinnikov, Sergey; Suzuki, Tomoharu

    We study the multicolor light curves for a number of metal-free core-collapse supernova (SN) models (25-100 ⊙ ) to determine the indicators for the detection and identification of first generation SNe. We use mixing-fallback supernova explosion models that explain the observed abundance patterns of metal-poor stars. Numerical calculations of the multicolor light curves are performed using the multigroup radiation hydrodynamic code STELLA. The calculated light curves of metal-free SNe are compared with solar-metallicity models and observed SNe. We conclude that the multicolor light curves could be used to identify first-generation SNe in current (Subaru/HSC) and future transient surveys (LSST, James Webb Space Telescope). They are also suitable for identifying low-metallicity SNe in the nearby universe (PTF, Pan-STARRS, Gaia).

  16. Diffuse Galactic antimatter from faint thermonuclear supernovae in old stellar populations

    Science.gov (United States)

    Crocker, Roland M.; Ruiter, Ashley J.; Seitenzahl, Ivo R.; Panther, Fiona H.; Sim, Stuart; Baumgardt, Holger; Möller, Anais; Nataf, David M.; Ferrario, Lilia; Eldridge, J. J.; White, Martin; Tucker, Brad E.; Aharonian, Felix

    2017-06-01

    Our Galaxy hosts the annihilation of a few 1043 low-energy positrons every second. Radioactive isotopes capable of supplying such positrons are synthesized in stars, stellar remnants and supernovae. For decades, however, there has been no positive identification of a main stellar positron source, leading to suggestions that many positrons originate from exotic sources like the Galaxy's central supermassive black hole or dark matter annihilation. Here we show that a single type of transient source, deriving from stellar populations of age 3-6 Gyr and yielding ∼0.03 M ⊙ of the positron emitter 44Ti, can simultaneously explain the strength and morphology of the Galactic positron annihilation signal and the Solar System abundance of the 44Ti decay product 44Ca. This transient is likely the merger of two low-mass white dwarfs, observed in external galaxies as the sub-luminous, thermonuclear supernova known as SN 1991bg-like.

  17. Point-source and diffuse high-energy neutrino emission from Type IIn supernovae

    Science.gov (United States)

    Petropoulou, M.; Coenders, S.; Vasilopoulos, G.; Kamble, A.; Sironi, L.

    2017-09-01

    Type IIn supernovae (SNe), a rare subclass of core collapse SNe, explode in dense circumstellar media that have been modified by the SNe progenitors at their last evolutionary stages. The interaction of the freely expanding SN ejecta with the circumstellar medium gives rise to a shock wave propagating in the dense SN environment, which may accelerate protons to multi-PeV energies. Inelastic proton-proton collisions between the shock-accelerated protons and those of the circumstellar medium lead to multimessenger signatures. Here, we evaluate the possible neutrino signal of Type IIn SNe and compare with IceCube observations. We employ a Monte Carlo method for the calculation of the diffuse neutrino emission from the SN IIn class to account for the spread in their properties. The cumulative neutrino emission is found to be ˜10 per cent of the observed IceCube neutrino flux above 60 TeV. Type IIn SNe would be the dominant component of the diffuse astrophysical flux, only if 4 per cent of all core collapse SNe were of this type and 20-30 per cent of the shock energy was channeled to accelerated protons. Lower values of the acceleration efficiency are accessible by the observation of a single Type IIn SN as a neutrino point source with IceCube using up-going muon neutrinos. Such an identification is possible in the first year following the SN shock breakout for sources within 20 Mpc.

  18. EARLY-TYPE HOST GALAXIES OF TYPE Ia SUPERNOVAE. I. EVIDENCE FOR DOWNSIZING

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yijung; Kim, Young-Lo; Lim, Dongwook; Chung, Chul; Lee, Young-Wook, E-mail: ywlee2@yonsei.ac.kr [Center for Galaxy Evolution Research and Department of Astronomy, Yonsei University, Seoul 03722 (Korea, Republic of)

    2016-03-15

    Type Ia supernova (SN Ia) cosmology provides the most direct evidence for the presence of dark energy. This result is based on the assumption that the lookback time evolution of SN Ia luminosity, after light curve corrections, would be negligible. Recent studies show, however, that the Hubble residual (HR) of SN Ia is correlated with the mass and morphology of host galaxies, implying the possible dependence of SN Ia luminosity on host galaxy properties. In order to investigate this more directly, we have initiated a spectroscopic survey for early-type host galaxies, for which population age and metallicity can be more reliably determined from the absorption lines. In this first paper of the series, we present here the results from high signal-to-noise ratio (≳100 per pixel) spectra for 27 nearby host galaxies in the southern hemisphere. For the first time in host galaxy studies, we find a significant (∼3.9σ) correlation between host galaxy mass (velocity dispersion) and population age, which is consistent with the “downsizing” trend among non-host early-type galaxies. This result is rather insensitive to the choice of population synthesis models. Since we find no correlation with metallicity, our result suggests that stellar population age is mainly responsible for the relation between host mass and HR. If confirmed, this would imply that the luminosity evolution plays a major role in the systematic uncertainties of SN Ia cosmology.

  19. He-accreting carbon-oxygen white dwarfs and Type Ia supernovae

    Science.gov (United States)

    Wang, Bo; Podsiadlowski, Philipp; Han, Zhanwen

    2017-12-01

    He accretion on to carbon-oxygen white dwarfs (CO WDs) plays a fundamental role when studying the formation of Type Ia supernovae (SNe Ia). Employing the mesa stellar evolution code, we calculated the long-term evolution of He-accreting CO WDs. Previous studies usually supposed that a WD can grow in mass to the Chandrasekhar limit in the stable He burning region and finally produce an SN Ia. However, in this study, we find that off-centre carbon ignition occurs in the stable He burning region if the accretion rate is above a critical value (˜2.05 × 10-6 M⊙ yr-1), resulting in accretion-induced collapse rather than an SN Ia. If the accretion rate is below the critical value, explosive carbon ignition will eventually happen in the centre producing an SN Ia. Taking into account the possibility of off-centre carbon ignition, we have re-determined the initial parameter space that produces SNe Ia in the He star donor channel, one of the promising channels to produce SNe Ia in young populations. Since this parameter space is smaller than was found in the previous study of Wang et al. (2009), the SN Ia rates are also correspondingly smaller. We also determined the chemical abundance profile of the He-accreting WDs at the moment of explosive carbon ignition, which can be used as initial input for SN Ia explosion models.

  20. Dust formation and the binary companions of supernovae

    Science.gov (United States)

    Kochanek, C. S.

    2017-11-01

    Supernovae (SNe) should both frequently have a binary companion at death and form significant amounts of dust. This implies that any binary companion must lie at the centre of an expanding dust cloud and the variable obscuration of the companion as the SN remnant expands will both unambiguously mark the companion and allow the measurement of the dust content through absorption rather than emission for decades after the explosion. However, sufficiently hot and luminous companions can suppress dust formation by rapidly photoionizing the condensible species in the ejecta. This provides a means of reconciling the Type IIb SNe Cas A, which lacks a luminous companion and formed a significant amount of dust (Md ≳ 0.1 M⊙), with the Type IIb SNe 1993J and 2011dh, both of which appear to have a luminous companion and to have formed a negligible amount of dust (Md ≲ 10-3 M⊙). The Crab and SN 1987A are consistent with this picture, as both lack a luminous companion and formed significant amounts of dust. An unrecognized dependence of dust formation on the properties of binary companions may help to explain why the evidence for dust formation in SNe appears so contradictory.

  1. The Rise and Fall of Type Ia Supernova Light Curves in the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Hayden, Brian T.; /Notre Dame U.; Garnavich, Peter M.; /Notre Dame U.; Kessler, Richard; /KICP, Chicago /Chicago U., EFI; Frieman, Joshua A.; /KICP, Chicago /Chicago U. /Fermilab; Jha, Saurabh W.; /Stanford U., Phys. Dept. /Rutgers U., Piscataway; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Cinabro, David; /Wayne State U.; Dilday, Benjamin; /Rutgers U., Piscataway; Kasen, Daniel; /UC, Santa Cruz; Marriner, John; /Fermilab; Nichol, Robert C.; /Portsmouth U., ICG /Baltimore, Space Telescope Sci. /Johns Hopkins U.

    2010-01-01

    We analyze the rise and fall times of Type Ia supernova (SN Ia) light curves discovered by the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. From a set of 391 light curves k-corrected to the rest-frame B and V bands, we find a smaller dispersion in the rising portion of the light curve compared to the decline. This is in qualitative agreement with computer models which predict that variations in radioactive nickel yield have less impact on the rise than on the spread of the decline rates. The differences we find in the rise and fall properties suggest that a single 'stretch' correction to the light curve phase does not properly model the range of SN Ia light curve shapes. We select a subset of 105 light curves well observed in both rise and fall portions of the light curves and develop a '2-stretch' fit algorithm which estimates the rise and fall times independently. We find the average time from explosion to B-band peak brightness is 17.38 {+-} 0.17 days, but with a spread of rise times which range from 13 days to 23 days. Our average rise time is shorter than the 19.5 days found in previous studies; this reflects both the different light curve template used and the application of the 2-stretch algorithm. The SDSS-II supernova set and the local SNe Ia with well-observed early light curves show no significant differences in their average rise-time properties. We find that slow-declining events tend to have fast rise times, but that the distribution of rise minus fall time is broad and single peaked. This distribution is in contrast to the bimodality in this parameter that was first suggested by Strovink (2007) from an analysis of a small set of local SNe Ia. We divide the SDSS-II sample in half based on the rise minus fall value, t{sub r} - t{sub f} {approx}< 2 days and t{sub r} - t{sub f} > 2 days, to search for differences in their host galaxy properties and Hubble residuals; we find no difference in host galaxy properties or Hubble

  2. A self-consistent analytical magnetar model: the luminosity of γ-ray burst supernovae is powered by radioactivity

    Science.gov (United States)

    Cano, Zach; Johansson Andreas, K. G.; Maeda, Keiichi

    2016-04-01

    We present an analytical model that considers energy arising from a magnetar central engine. The results of fitting this model to the optical and X-ray light curves of five long-duration γ-ray bursts (LGRBs) and two ultralong GRBs (ULGRBs), including their associated supernovae (SNe), show that emission from a magnetar central engine cannot be solely responsible for powering an LGRB-SN. While the early afterglow (AG)-dominated phase can be well described with our model, the predicted SN luminosity is underluminous by a factor of 3-17. We use this as compelling evidence that additional sources of heating must be present to power an LGRB-SN, which we argue must be radioactive heating. Our self-consistent modelling approach was able to successfully describe all phases of ULGRB 111209A/SN 2011kl, from the early AG to the later SN, where we determined for the magnetar central engine a magnetic field strength of 1.1-1.3 × 1015 G, an initial spin period of 11.5-13.0 ms, a spin-down time of 4.8-6.5 d, and an initial energy of 1.2-1.6 × 1050 erg. These values are entirely consistent with those determined by other authors. The luminosity of a magnetar-powered SN is directly related to how long the central engine is active, where central engines with longer durations give rise to brighter SNe. The spin-down time-scales of superluminous supernovae (SLSNe) are of order months to years, which provides a natural explanation as to why SN 2011kl was less luminous than SLSNe that are also powered by emission from magnetar central engines.

  3. PTF11mnb: First analog of supernova 2005bf. Long-rising, double-peaked supernova Ic from a massive progenitor

    Science.gov (United States)

    Taddia, F.; Sollerman, J.; Fremling, C.; Karamehmetoglu, E.; Quimby, R. M.; Gal-Yam, A.; Yaron, O.; Kasliwal, M. M.; Kulkarni, S. R.; Nugent, P. E.; Smadja, G.; Tao, C.

    2018-01-01

    Aims: We study PTF11mnb, a He-poor supernova (SN) whose light curves resemble those of SN 2005bf, a peculiar double-peaked stripped-envelope (SE) SN, until the declining phase after the main peak. We investigate the mechanism powering its light curve and the nature of its progenitor star. Methods: Optical photometry and spectroscopy of PTF11mnb are presented. We compared light curves, colors and spectral properties to those of SN 2005bf and normal SE SNe. We built a bolometric light curve and modeled this light curve with the SuperNova Explosion Code (SNEC) hydrodynamical code explosion of a MESA progenitor star and semi-analytic models. Results: The light curve of PTF11mnb turns out to be similar to that of SN 2005bf until 50 d when the main (secondary) peaks occur at -18.5 mag. The early peak occurs at 20 d and is about 1.0 mag fainter. After the main peak, the decline rate of PTF11mnb is remarkably slower than what was observed in SN 2005bf, and it traces well the 56Co decay rate. The spectra of PTF11mnb reveal a SN Ic and have no traces of He unlike in the case of SN Ib 2005bf, although they have velocities comparable to those of SN 2005bf. The whole evolution of the bolometric light curve is well reproduced by the explosion of a massive (Mej = 7.8 M⊙), He-poor star characterized by a double-peaked 56Ni distribution, a total 56Ni mass of 0.59 M⊙, and an explosion energy of 2.2 × 1051 erg. Alternatively, a normal SN Ib/c explosion (M(56Ni) = 0.11 M⊙, EK = 0.2 × 1051 erg, Mej = 1 M⊙) can power the first peak while a magnetar, with a magnetic field characterized by B = 5.0 × 1014 G, and a rotation period of P = 18.1 ms, provides energy for the main peak. The early g-band light curve can be fit with a shock-breakout cooling tail or an extended envelope model from which a radius of at least 30 R⊙ is obtained. Conclusions: We presented a scenario where PTF11mnb was the explosion of a massive, He-poor star, characterized by a double-peaked 56Ni

  4. AMEGO as a supernova alarm: alert, probe and diagnosis of Type Ia explosions

    Science.gov (United States)

    McEnery, Julie E.; Wang, Xilu

    2017-08-01

    A Type Ia supernova (SNIa) could go entirely unnoticed in the Milky Way and nearby starburst galaxies, due to the large optical and near-IR extinction in the dusty environment, low radio and X-ray luminosities, and a weak neutrino signal. But the recent SN2014J confirms that Type Ia supernovae emit γ-ray lines from 56Ni → 56Co → 56Fe radioactive decay, spanning 158 keV to 2.6 MeV. The Galaxy and nearby starbursts are optically thin to γ-rays, so the supernova line flux will suffer negligible extinction. The All-Sky Medium Energy Gamma-ray Observatory (AMEGO) will monitor the entire sky every 3 hours from ~200 keV to >10 GeV. Most of the SNIa gamma-ray lines are squarely within the AMEGO energy range. Thus AMEGO will be an ideal SNIa monitor and early warning system. We will show that the supernova signal is expected to emerge as distinct from the AMEGO background within days after the explosion in the SN2014J shell model. The early stage observations of SNIa will allow us to explore the progenitor types and the nucleosynthesis of SNIa. Moreover, with the excellent line sensitivity, AMEGO will be able to detect the SNIa at a rate of a few events per year and will obtain enough gamma-ray observations over the mission lifetimes (~10 SNIa) to sample the SNIa. The high SNIa detection rate will also enable the precise measurement of the 56Ni mass generated during the Type Ia explosion, which will help us test the cosmic distance calibration and probe the cosmic acceleration.

  5. The Effect of a Cosmic Ray Precursor in SN 1006?

    Science.gov (United States)

    Rakowski, Cara E.; Laming, J. Martin; Hwang, Una; Eriksen, Kristoffer A.; Ghavamian, Parviz; Hughes, John P.

    2011-07-01

    Like many young supernova remnants, SN 1006 exhibits what appear to be clumps of ejecta close to or protruding beyond the main blast wave. In this Letter, we examine three such protrusions along the east rim. They are semi-aligned with ejecta fingers behind the shock-front and exhibit emission lines from O VII and O VIII. We first interpret them in the context of an upstream medium modified by the saturated non-resonant Bell instability which enhances the growth of Rayleigh-Taylor instabilities when advected post-shock. We discuss their apparent periodicity if the spacing is determined by properties of the remnant or by a preferred size scale in the cosmic ray precursor. We also briefly discuss the alternative that these structures have an origin in the ejecta structure of the explosion itself. In this case, the young evolutionary age of SN 1006 would imply density structure within the outermost layers of the explosion with potentially important implications for deflagration and detonation in thermonuclear supernova explosion models.

  6. Research Update: Prediction of high figure of merit plateau in SnS and solid solution of (Pb,SnS

    Directory of Open Access Journals (Sweden)

    Shiqiang Hao

    2016-10-01

    Full Text Available Direct conversion between thermal and electrical energy can be achieved by thermoelectric materials, which provide a viable route for power generation and solid state refrigeration. Here, we use a combination of energetic, electronic, and vibrational first-principles based results to predict the figure of merit performance in hole doped single crystals of SnS and (Pb,SnS. We find high ZT values for both materials, specifically for (Pb,SnS along the b-axis. Both SnS and (Pb,SnS have excellent power factors when doped, due to a combination of increased electrical conductivity (due to doping and a significantly enhanced Seebeck coefficient obtained by a doping-induced multiband effect. Anharmonic phonon calculations combined with a Debye-Calloway model show that the lattice thermal conductivity of both compounds is low, due to intrinsic anharmonicity, and is lowered further by the random, solid solution nature of the cation sublattice of (Pb,SnS. (Pb,SnS exhibits a high ZT plateau ranging from 1.3 at 300 K to 1.9 at 800 K. The overall ZT of the hole doped (Pb,SnS crystals is predicted to outperform most of the current state-of-the-art thermoelectric sulfide materials.

  7. THE PROGENITOR OF SN 2011ja: CLUES FROM CIRCUMSTELLAR INTERACTION

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    Chakraborti, Sayan [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Ray, Alak; Yadav, Naveen [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Colaba, Mumbai 400 005 (India); Smith, Randall [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Ryder, Stuart [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia); Sutaria, Firoza [Indian Institute of Astrophysics, Koramangala, Bangalore (India); Dwarkadas, Vikram V. [Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Chandra, Poonam [Department of Physics, Royal Military College of Canada, Kingston, ON K7K 7B4 (Canada); Pooley, David [Department of Physics, Sam Houston State University, Huntsville, TX (United States); Roy, Rupak, E-mail: schakraborti@fas.harvard.edu [Aryabhatta Research Institute of Observational Sciences, Manora Peak, Nainital (India)

    2013-09-01

    Massive stars, possibly red supergiants, which retain extended hydrogen envelopes until core collapse, produce Type II plateau (IIP) supernovae. The ejecta from these explosions shocks the circumstellar matter originating from the mass loss of the progenitor during the final phases of its life. This interaction accelerates particles to relativistic energies which then lose energy via synchrotron radiation in the shock-amplified magnetic fields and inverse Compton scattering against optical photons from the supernova. These processes produce different signatures in the radio and X-ray parts of the electromagnetic spectrum. Observed together, they allow us to break the degeneracy between shock acceleration and magnetic field amplification. In this work, we use X-rays observations from the Chandra and radio observations fro