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1. Neutrino analysis of the September 2010 Crab Nebula flare and time-integrated constraints on neutrino emission from the Crab using IceCube

Author

Collaboration, I, Abbasi, R, Abdou, Y, Abu-Zayyad, T, Adams, J, Aguilar, JA, Ahlers, M, Altmann, D, Andeen, K, Auffenberg, J, Bai, X, Baker, M, Barwick, SW, Bay, R, Alba, JLB, Beattie, K, Beatty, JJ, Bechet, S, Becker, JK, Becker, K-H, Benabderrahmane, ML, BenZvi, S, Berdermann, J, Berghaus, P, Berley, D, Bernardini, E, Bertrand, D, Besson, DZ, Bindig, D, Bissok, M, Blaufuss, E, Blumenthal, J, Boersma, DJ, Bohm, C, Bose, D, Böser, S, Botner, O, Brown, AM, Buitink, S, Caballero-Mora, KS, Carson, M, Chirkin, D, Christy, B, Clem, J, Clevermann, F, Cohen, S, Colnard, C, Cowen, DF, D'Agostino, MV, Danninger, M, Daughhetee, J, Davis, JC, Clercq, CD, Demirörs, L, Denger, T, Depaepe, O, Descamps, F, Desiati, P, Vries-Uiterweerd, GD, DeYoung, T, Díaz-Vélez, JC, Dierckxsens, M, Dreyer, J, Dumm, JP, Ehrlich, R, Eisch, J, Ellsworth, RW, Engdegård, O, Euler, S, Evenson, PA, Fadiran, O, Fazely, AR, Fedynitch, A, Feintzeig, J, Feusels, T, Filimonov, K, Finley, C, Fischer-Wasels, T, Foerster, MM, Fox, BD, Franckowiak, A, Franke, R, Gaisser, TK, Gallagher, J, Gerhardt, L, Gladstone, L, Glüsenkamp, T, Goldschmidt, A, Goodman, JA, Gora, D, Grant, D, Griesel, T, Groß, A, Grullon, S, Gurtner, M, Ha, C, Hajismail, A, Hallgren, A, Halzen, F, Han, K, Hanson, K, Heinen, D, Helbing, K, Herquet, P, Hickford, S, Hill, GC, Hoffman, KD, Homeier, A, Hoshina, K, Hubert, D, Huelsnitz, W, Hülß, J-P, Hulth, PO, Hultqvist, K, Hussain, S, Ishihara, A, Jacobsen, J, Japaridze, GS, Johansson, H, Joseph, JM, Kampert, K-H, Kappes, A, Karg, T, Karle, A, Kenny, P, Kiryluk, J, Kislat, F, Klein, SR, Köhne, J-H, Kohnen, G, Kolanoski, H, Köpke, L, Kopper, S, Koskinen, DJ, Kowalski, M, Kowarik, T, Krasberg, M, Krings, T, Kroll, G, Kurahashi, N, Kuwabara, T, Labare, M, Lafebre, S, Laihem, K, Landsman, H, Larson, MJ, Lauer, R, Lünemann, J, Madajczyk, B, Madsen, J, Majumdar, P, Marotta, A, Maruyama, R, Mase, K, Matis, HS, Meagher, K, Merck, M, Mészáros, P, Meures, T, Middell, E, Milke, N, Miller, J, Montaruli, T, Morse, R, Movit, SM, Nahnhauer, R, Nam, JW, Naumann, U, Nießen, P, Nygren, DR, Odrowski, S, Olivas, A, Olivo, M, O'Murchadha, A, Ono, M, Panknin, S, Paul, L, Heros, CPDL, Petrovic, J, Piegsa, A, Pieloth, D, Porrata, R, Posselt, J, Price, CC, Price, PB, Przybylski, GT, Rawlins, K, Redl, P, Resconi, E, Rhode, W, Ribordy, M, Rizzo, A, Rodrigues, JP, Roth, P, Rothmaier, F, Rott, C, Ruhe, T, Rutledge, D, Ruzybayev, B, Ryckbosch, D, Sander, H-G, Santander, M, Sarkar, S, Schatto, K, Schmidt, T, Schönwald, A, Schukraft, A, Schultes, A, Schulz, O, Schunck, M, Seckel, D, Semburg, B, Seo, SH, Sestayo, Y, Seunarine, S, Silvestri, A, Slipak, A, Spiczak, GM, Spiering, C, Stamatikos, M, Stanev, T, Stephens, G, Stezelberger, T, Stokstad, RG, Stössl, A, Stoyanov, S, Strahler, EA, Straszheim, T, Stür, M, Sullivan, GW, Swillens, Q, Taavola, H, Taboada, I, Tamburro, A, Tepe, A, Ter-Antonyan, S, Tilav, S, Toale, PA, Toscano, S, Tosi, D, Turčan, D, Eijndhoven, NV, Vandenbroucke, J, Overloop, AV, Santen, JV, Vehring, M, Voge, M, Walck, C, Waldenmaier, T, Wallraff, M, Walter, M, Weaver, C, Wendt, C, Westerhoff, S, Whitehorn, N, Wiebe, K, Wiebusch, CH, Williams, DR, Wischnewski, R, Wissing, H, Wolf, M, Wood, TR, Woschnagg, K, Xu, C, Xu, XW, Yodh, G, Yoshida, S, Zarzhitsky, P, and Zoll, M

Subjects
System, Signals, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Gamma-Ray Flares, 01 natural sciences, 7. Clean energy, Spectral line, pulsars: individual (Crab Pulsar), law.invention, law, Pulsar Winds, 0103 physical sciences, 010306 general physics, 010303 astronomy & astrophysics, ISM: supernova remnants, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Spectral index, Muon, neutrinos, Astronomy and Astrophysics, Fermi acceleration, gamma rays: general, High-Energy Neutrinos, Crab Nebula, 13. Climate action, Space and Planetary Science, High Energy Physics::Experiment, Neutrino, Astrophysics - High Energy Astrophysical Phenomena, Flare, Fermi Gamma-ray Space Telescope, Telescopes
Abstract

We present the results of a search for high-energy muon neutrinos with the IceCube detector in coincidence with the Crab Nebula flare reported on 2010 September by various experiments. Due to the unusual flaring state of the otherwise steady source we performed a prompt analysis of the 79-string configuration data to search for neutrinos that might be emitted along with the observed. gamma-rays. We performed two different and complementary data selections of neutrino events in the time window of 10 days around the flare. One event selection is optimized for discovery of E-upsilon(2). neutrino spectrum typical of first-order Fermi acceleration. A similar event selection has also been applied to the 40-string data to derive the time-integrated limits to the neutrino emission from the Crab. The other event selection was optimized for discovery of neutrino spectra with softer spectral index and TeV energy cutoffs as observed for various Galactic sources in. gamma-rays. The 90% confidence level (CL) best upper limits on the Crab flux during the 10 day flare are 4.73 x 10(-11) cm(-2) s(-1) TeV-1 for an E-upsilon(2). neutrino spectrum and 2.50 x 10(-10) cm(-2) s(-1) TeV-1 for a softer neutrino spectra of E-upsilon(-2.7), as indicated by Fermi measurements during the flare. In this paper, we also illustrate the impact of the time-integrated limit on the Crab neutrino steady emission. The limit obtained using 375.5 days of the 40-string configuration is compared to existing models of neutrino production from the Crab and its impact on astrophysical parameters is discussed. The most optimistic predictions of some models are already rejected by the IceCube neutrino telescope with more than 90% CL.

Published
2011
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2. SEARCH FOR HIGH-ENERGY MUON NEUTRINOS FROM THE 'NAKED-EYE' GRB 080319B WITH THE ICECUBE NEUTRINO TELESCOPE (vol 701, pg 1721, 2009)

Author

Abbasi, R, Abdou, Y, Ackermann, M, Adams, J, Ahlers, M, Andeen, K, Auffenberg, J, Bai, X, Baker, M, Barwick, SW, Bay, R, Alba, JLB, Beattie, K, Bechet, S, Becker, JK, Becker, K-H, Benabderrahmane, ML, Berdermann, J, Berghaus, P, Berley, D, Bernardini, E, Bertrand, D, Besson, DZ, Bissok, M, Blaufuss, E, Boersma, DJ, Bohm, C, Bolmont, J, Boeser, S, Botner, O, Bradley, L, Braun, J, Breder, D, Burgess, T, Castermans, T, Chirkin, D, Christy, B, Clem, J, Cohen, S, Cowen, DF, D'Agostino, MV, Danninger, M, Day, CT, De Clercq, C, Demiroers, L, Depaepe, O, Descamps, F, Desiati, P, de Vries-Uiterweerd, G, DeYoung, T, Diaz-Velez, JC, Dreyer, J, Dumm, JP, Duvoort, MR, Edwards, WR, Ehrlich, R, Eisch, J, Ellsworth, RW, Engdegard, O, Euler, S, Evenson, PA, Fadiran, O, Fazely, AR, Feusels, T, Filimonov, K, Finley, C, Foerster, MM, Fox, BD, Franckowiak, A, Franke, R, Gaisser, TK, Gallagher, J, Ganugapati, R, Gerhardt, L, Gladstone, L, Goldschmidt, A, Goodman, JA, Gozzini, R, Grant, D, Griesel, T, Gross, A, Grullon, S, Gunasingha, RM, Gurtner, M, Ha, C, Hallgren, A, Halzen, F, Han, K, Hanson, K, Hasegawa, Y, Heise, J, Helbing, K, Herquet, P, Hickford, S, Hill, GC, Hoffman, KD, Hoshina, K, Hubert, D, Huelsnitz, W, Huelss, J-P, Hulth, PO, Hultqvist, K, Hussain, S, Imlay, RL, Inaba, M, Ishihara, A, Jacobsen, J, Japaridze, GS, Johansson, H, Joseph, JM, Kampert, K-H, Kappes, A, Karg, T, Karle, A, Kelley, JL, Kenny, P, Kiryluk, J, Kislat, F, Klein, SR, Klepser, S, Knops, S, Kohnen, G, Kolanoski, H, Koepke, L, Kowalski, M, Kowarik, T, Krasberg, M, Kuehn, K, Kuwabara, T, Labare, M, Laihem, K, Landsman, H, Lauer, R, Leich, H, Lennarz, D, Lucke, A, Lundberg, J, Luenemann, J, Madsen, J, Majumdar, P, Maruyama, R, Mase, K, Matis, HS, McParland, CP, Meagher, K, Merck, M, Meszaros, P, Middell, E, Milke, N, Miyamoto, H, Mohr, A, Montaruli, T, Morse, R, Movit, SM, Muenich, K, Nahnhauer, R, Nam, JW, Nieen, P, Nygren, DR, Odrowski, S, Olivas, A, Olivo, M, Ono, M, Panknin, S, Patton, S, de los Heros, CP, Petrovic, J, Piegsa, A, Pieloth, D, Pohl, AC, Porrata, R, Potthoff, N, Price, PB, Prikockis, M, Przybylski, GT, Rawlins, K, Redl, P, Resconi, E, Rhode, W, Ribordy, M, Rizzo, A, Rodrigues, JP, Roth, P, Rothmaier, F, Rott, C, Roucelle, C, Rutledge, D, Ryckbosch, D, Sander, H-G, Sarkar, S, Satalecka, K, Schlenstedt, S, Schmidt, T, Schneider, D, Schukraft, A, Schulz, O, Schunck, M, Seckel, D, Semburg, B, Seo, SH, Sestayo, Y, Seunarine, S, Silvestri, A, Slipak, A, Spiczak, GM, Spiering, C, Stamatikos, M, Stanev, T, Stephens, G, Stezelberger, T, Stokstad, RG, Stoufer, MC, Stoyanov, S, Strahler, EA, Straszheim, T, Sulanke, K-H, Sullivan, GW, Swillens, Q, Taboada, I, Tarasova, O, Tepe, A, Ter-Antonyan, S, Terranova, C, Tilav, S, Tluczykont, M, Toale, PA, Tosi, D, Turcan, D, van Eijndhoven, N, Vandenbroucke, J, Van Overloop, A, Voigt, B, Walck, C, Waldenmaier, T, Walter, M, Wendt, C, Westerhoff, S, Whitehorn, N, Wiebusch, CH, Wiedemann, A, Wikstroem, G, Williams, DR, Wischnewski, R, Wissing, H, Woschnagg, K, Xu, XW, Yodh, G, Yoshida, S, and Collaboration, I

Published
2010

3. Erratum: Search for high-energy Muon neutrinos from the 'naked-eye' GRB080319b with the icecube neutrino telescope (The Astrophysical Journal (2009) 701 (1721))

Author

Abbasi, R., Abdou, Y., Ackermann, M., Adams, J., Ahlers, M., Andeen, K., Auffenberg, J., Bai, X., Baker, M., Barwick, S. W., Bay, R., Alba, J. L. B., Beattie, K., Bechet, S., Becker, J. K., Becker, K. -H., Benabderrahmane, M. L., Berdermann, J., Berghaus, P., Berley, D., Bernardini, E., Bertrand, D., Besson, D. Z., Bissok, M., Blaufuss, E., Boersma, D. J., Bohm, C., Bolmont, J., Boser, S., Botner, O., Bradley, L., Braun, J., Breder, D., Burgess, T., Castermans, T., Chirkin, D., Christy, B., Clem, J., Cohen, S., Cowen, D. F., D'Agostino, M. V., Danninger, M., Day, C. T., De Clercq, C., Demirors, L., Depaepe, O., Descamps, F., Desiati, P., De Vries-Uiterweerd, G., Deyoung, T., Diaz-Velez, J. C., Dreyer, J., Dumm, J. P., Duvoort, M. R., Edwards, W. R., Ehrlich, R., Eisch, J., Ellsworth, R. W., Engdegrd, O., Euler, S., Evenson, P. A., Fadiran, O., Fazely, A. R., Feusels, T., Filimonov, K., Finley, C., Foerster, M. M., Fox, B. D., Franckowiak, A., Franke, R., Gaisser, T. K., Gallagher, J., Ganugapati, R., Gerhardt, L., Gladstone, L., Goldschmidt, A., Goodman, J. A., Gozzini, R., Grant, D., Griesel, T., Gro, A., Grullon, S., Gunasingha, R. M., Gurtner, M., Ha, C., Hallgren, A., Halzen, F., Han, K., Hanson, K., Hasegawa, Y., Heise, J., Helbing, K., Herquet, P., Hickford, S., Hill, G. C., Hoffman, K. D., Hoshina, K., Hubert, D., Huelsnitz, W., Hul, J. -P., Hulth, P. O., Hultqvist, K., Hussain, S., Imlay, R. L., Inaba, M., Ishihara, A., Jacobsen, J., Japaridze, G. S., Johansson, H., Joseph, J. M., Kampert, K. -H., Kappes, A., Karg, T., Karle, A., Kelley, J. L., Kenny, P., Kiryluk, J., Kislat, F., Klein, S. R., Klepser, S., Knops, S., Kohnen, G., Kolanoski, H., Kopke, L., Kowalski, M., Kowarik, T., Krasberg, M., Kuehn, K., Kuwabara, T., Labare, M., Laihem, K., Landsman, H., Lauer, R., Leich, H., Lennarz, D., Lucke, A., Lundberg, J., Lunemann, J., Madsen, J., Majumdar, P., Maruyama, R., Mase, K., Matis, H. S., Mcparland, C. P., Meagher, K., Merck, M., Meszros, P., Middell, E., Milke, N., Miyamoto, H., Mohr, A., Montaruli, T., Morse, R., Movit, S. M., Munich, K., Nahnhauer, R., Nam, J. W., Nieen, P., Nygren, D. R., Odrowski, S., Olivas, A., Olivo, M., Ono, M., Panknin, S., Patton, S., Heros, C. P. D. L., Petrovic, J., Piegsa, A., Pieloth, D., Pohl, A. C., Porrata, R., Potthoff, N., Price, P. B., Prikockis, M., Przybylski, G. T., Rawlins, K., Redl, P., Resconi, E., Rhode, W., Ribordy, M., Rizzo, A., Rodrigues, J. P., Roth, P., Rothmaier, F., Rott, C., Roucelle, C., Rutledge, D., Ryckbosch, D., Sander, H. -G., Sarkar, S., Satalecka, K., Schlenstedt, S., Schmidt, T., Schneider, D., Schukraft, A., Schulz, O., Schunck, M., Seckel, D., Semburg, B., Seo, S. H., Sestayo, Y., Seunarine, S., Silvestri, A., Slipak, A., Spiczak, G. M., Spiering, C., Stamatikos, M., Stanev, T., Stephens, G., Stezelberger, T., Stokstad, R. G., Stoufer, M. C., Stoyanov, S., Strahler, E. A., Straszheim, T., Sulanke, K. -H., Sullivan, G. W., Swillens, Q., Taboada, I., Tarasova, O., Tepe, A., Ter-Antonyan, S., Terranova, C., Tilav, S., Tluczykont, M., Toale, P. A., Tosi, D., Turan, D., Van Eijndhoven, N., Vandenbroucke, J., Van Overloop, A., Voigt, B., Walck, C., Waldenmaier, T., Walter, M., Wendt, C., Westerhoff, S., Whitehorn, N., Wiebusch, C. H., Wiedemann, A., Wikstrom, G., Williams, D. R., Wischnewski, R., Wissing, H., Woschnagg, K., X. W., Xu, Yodh, G., and Yoshida, S.

Published
2010

4. GIANT GROUND LEVEL ENHANCEMENT OF RELATIVISTIC SOLAR PROTONS ON 2005 JANUARY 20. I. SPACESHIP EARTH OBSERVATIONS.

Author

BIEBER, J. W., CLEM, J., EVENSON, P., PYLE, R., SÀIZ, A., and RUFFOLO, D.

Subjects
*INTERPLANETARY medium, *SOLAR-terrestrial physics, *CORONAL mass ejections, *PARTICLE emissions, *ANISOTROPY, *PROTONS, *EARTH (Planet), *SUN
Abstract

A ground level enhancement (GLE) is a solar event that accelerates ions (mostly protons) to GeV range energies in such great numbers that ground-based detectors, such as neutron monitors, observe their showers in Earth's atmosphere above the Galactic cosmic ray background. GLEs are of practical interest because an enhanced relativistic ion flux poses a hazard to astronauts, air crews, and aircraft electronics, and provides the earliest direct indication of an impending space radiation storm. The giant GLE of 2005 January 20 was the second largest on record (and largest since 1956), with up to 4200% count rate enhancement at sea level. We analyzed data from the Spaceship Earth network, supplemented to comprise 13 polar neutron monitor stations with distinct asymptotic viewing directions and Polar Bare neutron counters at South Pole, to determine the time evolution of the relativistic proton density, energy spectrum, and three-dimensional directional distribution.We identify two energy-dispersive peaks, indicating two solar injections. The relativistic solar protons were initially strongly beamed, with a peak maximum-to-minimum anisotropy ratio over 1000:1. The directional distribution is characterized by an axis of symmetry, determined independently for each minute of data, whose angle from the magnetic field slowly varied from about 60° to low values and then rose to about 90°. The extremely high relativistic proton flux from certain directions allowed 10 s tracking of count rates, revealing fluctuations of period ⩾2minutes with up to 50% fractional changes, which we attribute to fluctuations in the axis of symmetry. [ABSTRACT FROM AUTHOR]

Published
2013
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5. THREE-DIMENSIONAL WAVY HELIOSPHERIC CURRENT SHEET DRIFTS.

Author

Pei, C., Bieber, J. W., Burger, R. A., and Clem, J.

Subjects
HELIOSPHERE, MAGNETIC fields, GALACTIC cosmic rays, ASTROPHYSICAL radiation, ELECTROMAGNETIC waves
Abstract

We present an analytic method to determine the directions of the three-dimensional (3D) heliospheric current sheet (HCS) drift for any tilt angle based on Parker's heliospheric magnetic field and compare it with published two-dimensional and quasi-3D methods. We also present a new approach to determine the magnitude of the 3D HCS drift numerically. Implications of these new methods for the solar modulation of Galactic cosmic rays are considered and compared with results from prior methods reported in the literature. Our results support the concept that HCS drift plays an important role in the solar modulation of cosmic rays. [ABSTRACT FROM AUTHOR]

Published
2012
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6. THE FIRST LIMITS ON THE ULTRA-HIGH ENERGY NEUTRINO FLUENCE FROM GAMMA-RAY BURSTS.

Author

VIEREGG, A. G., PALLADINO, K., ALLISON, P., BAUGHMAN, B. M., BEATTY, J. J., BELOV, K., BESSON, D. Z., BEVAN, S., BINNS, W. R., CHEN, C., CHEN, P., CLEM, J. M., CONNOLLY, A., DETRIXHE, M., DE MARCO, D., DOWKONTT, P. F., DUVERNOIS, M., GORHAM, P. W., GRASHORN, E. W., and HILL, B.

Subjects
SOLAR neutrinos, GAMMA ray bursts, ROCKET payloads, SOLAR atmosphere, SPACE exploration
Abstract

We set the first limits on the ultra-high energy (UHE) neutrino fluence at energies greater than 109 GeV from gamma-ray bursts (GRBs) based on data from the second flight of the Antarctic Impulsive Transient Antenna (ANITA). During the 31 day flight of ANITA-II, 26 GRBs were recorded by Swift or Fermi. Of these, we analyzed the 12 GRBs which occurred during quiet periods when the payload was away from anthropogenic activity. In a blind analysis, we observe 0 events on a total background of 0.0044 events in the combined prompt window for all 12 low-background bursts. We also observe 0 events from the remaining 14 bursts. We place a 90% confidence level limit on the E-4 prompt neutrino fluence between 108 GeV < E < 1012 GeV of E4Φ = 2.5 x 1017 GeV³ cm-2 from GRB090107A. This is the first reported limit on the UHE neutrino fluence from GRBs above 109 GeV, and the strongest limit above 108 GeV. [ABSTRACT FROM AUTHOR]

Published
2011
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8. LATITUDE SURVEY INVESTIGATION OF GALACTIC COSMIC RAY SOLAR MODULATION DURING 1994-2007.

Author

Nuntiyakul, W., Evenson, P., Ruffolo, D., Sáiz, A., Bieber, J. W., Clem, J., Pyle, R., Duldig, M. L., and Humble, J. E.

Subjects
COSMIC rays, GALACTIC nuclei, NEUTRONS, MAGNETIC fields, SPECTRUM analysis, TURBULENCE
Abstract

The Galactic cosmic ray spectrum exhibits subtle variations over the 22 yr solar magnetic cycle in addition to the more dramatic variations over the 11 yr sunspot cycle. Neutron monitors are large ground-based detectors that provide accurate measurements of variations in the cosmic ray flux at the top of the atmosphere above the detector. At any given location the magnetic field of the Earth excludes particles below a well-defined rigidity (momentum per unit charge) known as the cutoff rigidity, which can be accurately calculated using detailed models of the geomagnetic field. By carrying a neutron monitor to different locations, e.g., on a ship, the Earth itself serves as a magnet spectrometer. By repeating such latitude surveys with identical equipment, a sensitive measurement of changes in the spectrum can be made. In this work, we analyze data from the 1994 through 2007 series of latitude surveys conducted by the Bartol Research Institute, the University of Tasmania, and the Australian Antarctic Division. We confirm the curious “crossover” in spectra measured near solar minima during epochs of opposite solar magnetic polarity, and show that it is directly related to a sudden change in the spectral behavior of solar modulation at the time of the polarity reversal, as revealed from contemporaneous variations in the survey data and a fixed station. We suggest that the spectral change and crossover result from the interaction of effects due to gradient/curvature drifts with a systematic change in the interplanetary diffusion coefficient caused by turbulent magnetic helicity. [ABSTRACT FROM AUTHOR]

Published
2014
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9. OPTICAL AND INFRARED ANALYSIS OF TYPE II SN 2006bc.

Author

Gallagher, Joseph S., Sugerman, B. E. K., Clayton, Geoffrey C., Andrews, J. E., Clem, J., Barlow, M. J., Ercolano, B., Fabbri, J., Otsuka, M., Wesson, R., and Meixner, M.

Subjects
SUPERNOVAE spectra, COSMIC dust, CIRCUMSTELLAR matter, RADIATIVE transfer, INFRARED imaging
Abstract

We present nebular phase optical imaging and spectroscopy and near/mid-IR imaging of the Type II SN 2006bc. Observations reveal the central wavelength of the symmetric Hα line profile to be redshifted with respect to the host galaxy Hα emission by day 325. Such a phenomenon has been argued to result from an asymmetric explosion in the iron-peak elements resulting in a larger mass of 56Ni and higher excitation of hydrogen on the far side of the supernova (SN) explosion. We also observe a gradual blueshifting of this Hα peak which is indicative of dust formation in the ejecta. Although showing a normal peak brightness, V ∼ –17.2, for a core-collapse SN, 2006bc fades by ∼6 mag during the first 400 days suggesting either a relatively low 56Ni yield, an increase in extinction due to new dust, or both. A short-duration flattening of the light curve is observed from day 416 to day 541 suggesting an optical light echo. Based on the narrow time window of this echo, we discuss implications on the location and geometry of the reflecting interstellar medium. With our radiative transfer models, we find an upper limit of 2 × 10–3M☼ of dust around SN 2006bc. In the event that all of this dust were formed during the SN explosion, this quantity of dust is still several orders of magnitude lower than that needed to explain the large quantities of dust observed in the early universe. [ABSTRACT FROM AUTHOR]

Published
2012
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