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1. No Evidence for Variability of Intervening Absorption Lines toward GRB 060206: Implications for the Mg II Incidence Problem

Author

Aoki, Kentaro, Totani, Tomonori, Hattori, Takashi, Ohta, Kouji, Kawabata, Koji S., Kobayashi, Naoto, Iye, Masanori, Nomoto, Ken-ichi, and Kawai, Nobuyuki

Subjects
Astrophysics
Abstract

We examine variability of absorption line strength of intervening systems along the line of sight to GRB 060206 at $z = 4.05$, by the low-resolution optical spectra obtained by the Subaru telescope from six to ten hours after the burst. Strong variabilities of Fe\emissiontype{II} and Mg\emissiontype{II} lines at $z=1.48$ during $t=$5--8 hours have been reported for this GRB \citep{Hao07}, and this has been used to support the idea of clumpy Mg\emissiontype{II} cloudlets that was originally proposed to explain the anomalously high incidence of Mg\emissiontype{II} absorbers in GRB spectra compared with quasars . However, our spectra with higher signal-to-noise ratio do not show any evidence for variability in $t=$6-10 hours. There is a clear discrepancy between our data and Hao et al. data in the overlapping time interval. Furthermore, the line strengths in our data are in good agreement with those observed at $t \sim$ 2 hours by \citet{Tho08}. We also detected Fe\emissiontype{II} and Mg\emissiontype{II} absorption lines for a system at $z = 2.26$, and these lines do not show evidence for variability either. Therefore we conclude that there is no strong evidence for variability of intervening absorption lines toward GRB 060206, significantly weakening the support to the Mg\emissiontype{II} cloudlet hypothe sis by the GRB 060206 data., Comment: Accepted for publication in PASJ. Figs. 7-9 for Fe II 2249.9, 2260.8, 2344.2, 2374.5 and 2382.8 at z=2.26 are added. Fig. 11 for 4 hours spectrum and table 3. for all detected absorption lines are added, too

Published
2008
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2. Keck and ESO-VLT View of the Symmetry of the Ejecta of the XRF/SN 2006aj

Author

Mazzali, Paolo A., Foley, Ryan J., Deng, Jinsong, Patat, Ferdinando, Pian, Elena, Baade, Dietrich, Bloom, Joshua S., Filippenko, Alexei V., Perley, Daniel A., Valenti, Stefano, Wang, Lifan, Kawabata, Koji, Maeda, Keiichi, and Nomoto, Ken-ichi

Subjects
Astrophysics
Abstract

Nebular-phase spectra of SN 2006aj, which was discovered in coincidence with X-ray flash 060218, were obtained with Keck in 2006 July and the Very Large Telescope in 2006 September. At the latter epoch spectropolarimetry was also attempted, yielding an upper limit of ~ 2% for the polarization. The spectra show strong emission lines of [OI] and MgI], as expected from a Type Ic supernova, but weak CaII lines. The [FeII] lines that were strong in the spectra of SN 1998bw are much weaker in SN 2006aj, consistent with the lower luminosity of this SN. The outer velocity of the line-emitting ejecta is ~ 8000 km/s in July and ~ 7400 km/s in September, consistent with the relatively low kinetic energy of expansion of SN 2006aj. All emission lines have similar width, and the profiles are symmetric, indicating that no major asymmetries are present in the ejecta at the velocities sampled by the nebular lines (v < 8000 km/s), except perhaps in the innermost part. The spectra were modelled with a non-LTE code. The mass of 56Ni required to power the emission spectrum is ~ 0.20 Msun, in excellent agreement with the results of early light curve modelling. The oxygen mass is ~ 1.5 Msun, again much less than in SN 1998bw but larger by ~ 0.7 Msun than the value derived from the early-time modelling. The total ejected mass is ~ 2 Msun below 8000 km/s. This confirms that SN 2006aj was only slightly more massive and energetic than the prototypical Type Ic SN 1994I, but also indicates the presence of a dense inner core, containing ~ 1 Msun of mostly oxygen and carbon. The presence of such a core is inferred for all broad-lined SNe Ic. This core may have the form of an equatorial oxygen-dominated region, but it is too deep to affect the early light curve and too small to affect the late polarization spectrum., Comment: 20 pages, 6 figures. Accepted for publication in the Astrophysical Journal

Published
2007
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3. Nucleosynthetic signatures of the first stars

Author

Frebel, Anna, Aoki, Wako, Christlieb, Norbert, Ando, Hiroyasu, Asplund, Martin, Barklem, Paul S., Beers, Timothy C., Eriksson, Kjell, Fechner, Cora, Fujimoto, Masayuki Y., Honda, Satoshi, Kajino, Toshitaka, Minezaki, Takeo, Nomoto, Ken`ichi, Norris, John E., Ryan, Sean G., Takada-Hidai, Masahide, Tsangarides, Stelios, and Yoshii, Yuzuru

Subjects
Astrophysics
Abstract

The chemically most primitive stars provide constraints on the nature of the first stellar objects that formed in the Universe; elements other than hydrogen, helium and traces of lithium within these objects were generated by nucleosynthesis in the very first stars. The relative abundances of elements in the surviving primitive stars reflect the masses of the first stars, because the pathways of nucleosynthesis are quite sensitive to stellar masses. Several models have been suggested to explain the origin of the abundance pattern of the giant star HE 0107-5240, which hitherto exhibited the highest deficiency of heavy elements known. Here we report the discovery of HE 1327-2326, a subgiant or main-sequence star with an iron abundance about a factor of two lower than that of HE 0107-5240. Both stars show extreme overabundances of carbon and nitrogen with respect to iron, suggesting a similar origin of the abundance patterns. The unexpectedly low Li and high Sr abundances of HE 1327-2326, however, challenge existing theoretical understanding: none predicts the high Sr abundance or provides a Li depletion mechanism consistent with data available for the most metal-poor stars., Comment: 9 pages, 2 figures, accepted for publication in Nature; typos corrected

Published
2005
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4. A hybrid type Ia supernova with an early flash triggered by helium-shell detonation

Author

Jiang, Ji-an, Doi, Mamoru, Maeda, Keiichi, Shigeyama, Toshikazu, Nomoto, Kenʼichi, Yasuda, Naoki, Jha, Saurabh W., Tanaka, Masaomi, Morokuma, Tomoki, Tominaga, Nozomu, Ivezi⊗, Zeljko, Ruiz-Lapuente, Pilar, Stritzinger, Maximilian D., Mazzali, Paolo A., Ashall, Christopher, Mould, Jeremy, Baade, Dietrich, Suzuki, Nao, Connolly, Andrew J., Patat, Ferdinando, Wang, Lifan, Yoachim, Peter, Jones, David, Furusawa, Hisanori, and Miyazaki, Satoshi

Published
2017
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6. Catching Element Formation In The Act. The Case for a New MeV Gamma-Ray Mission: Radionuclide Astronomy in the 2020s. A White Paper for the 2020 Decadal Survey

Author

Fryer, Chris L., Timmes, Frank, Hungerford, Aimee L., Couture, Aaron, Adams, Fred, Aoki, Wako, Arcones, Almudena, Arnett, David, Auchettl, Katie, Avila, Melina, Badenes, Carles, Baron, Eddie, Bauswein, Andreas, John Beacom, Blackmon, Jeff, Blondin, Stéphane, Bloser, Peter, Boggs, Steve, Boss, Alan, Brandt, Terri, Bravo, Eduardo, Brown, E., Brown, Peter, Bruenn, Steve, Budtz-Jørgensen, Carl, Burns, Eric, Calder, Alan, Caputo, Regina, Champagne, Art, Chevalier, Roger, Chieffi, Alessandro, Chipps, Kelly, Cinabro, David, Clarkson, Ondrea, Clayton, Don, Coc, Alain, Connolly, Devin, Conroy, Charlie, Côté, Benoit, Couch, Sean, Dauphas, Nicolas, Deboer, Richard James, Deibel, Catherine, Denisenkov, Pavel, Desch, Steve, Dessart, Luc, Diehl, Roland, Doherty, Carolyn, Domínguez, Inma, Dong, Subo, Dwarkadas, Vikram, Fan, Doreen, Fields, Brian, Fields, Carl, Filippenko, Alex, Fisher, Robert, Foucart, Francois, Fransson, Claes, Fröhlich, Carla, Fuller, George, Gibson, Brad, Giryanskaya, Viktoriya, Görres, Joachim, Goriely, Stéphane, Grebenev, Sergei, Grefenstette, Brian, Grohs, Evan, Guillochon, James, Harpole, Alice, Harris, Chelsea, Austin Harris, J., Harrison, Fiona, Hartmann, Dieter, Hashimoto, Masa-Aki, Heger, Alexander, Hernanz, Margarita, Herwig, Falk, Hirschi, Raphael, Hix, Raphael William, Höflich, Peter, Hoffman, Robert, Holcomb, Cole, Hsiao, Eric, Iliadis, Christian, Janiuk, Agnieszka, Janka, Thomas, Jerkstrand, Anders, Johns, Lucas, Jones, Samuel, José, Jordi, Kajino, Toshitaka, Karakas, Amanda, Karpov, Platon, Kasen, Dan, Kierans, Carolyn, Kippen, Marc, Korobkin, Oleg, Kobayashi, Chiaki, Kozma, Cecilia, Krot, Saha, Kumar, Pawan, Kuvvetli, Irfan, Laird, Alison, Laming, Martin, Larsson, Josefin, Lattanzio, John, Lattimer, James, Leising, Mark, Lennarz, Annika, Lentz, Eric, Limongi, Marco, Lippuner, Jonas, Livne, Eli, Lloyd-Ronning, Nicole, Longland, Richard, Lopez, Laura A., Lugaro, Maria, Lutovinov, Alexander, Madsen, Kristin, Malone, Chris, Matteucci, Francesca, Mcenery, Julie, Meisel, Zach, Messer, Bronson, Metzger, Brian, Meyer, Bradley, Meynet, Georges, Mezzacappa, Anthony, Miller, Jonah, Miller, Richard, Milne, Peter, Misch, Wendell, Mitchell, Lee, Mösta, Philipp, Motizuki, Yuko, Müller, Bernhard, Mumpower, Matthew, Murphy, Jeremiah, Nagataki, Shigehiro, Nakar, Ehud, Nomoto, Ken Ichi, Nugent, Peter, Nunes, Filomena, O Shea, Brian, Oberlack, Uwe, Pain, Steven, Parker, Lucas, Perego, Albino, Pignatari, Marco, Pinedo, Gabriel Martínez, Plewa, Tomasz, Poznanski, Dovi, Priedhorsky, William, Pritychenko, Boris, Radice, David, Ramirez-Ruiz, Enrico, Rauscher, Thomas, Reddy, Sanjay, Rehm, Ernst, Reifarth, Rene, Richman, Debra, Ricker, Paul, Rijal, Nabin, Roberts, Luke, Röpke, Friedrich, Rosswog, Stephan, Ruiter, Ashley J., Ruiz, Chris, Savin, Daniel Wolf, Schatz, Hendrik, Schneider, Dieter, Schwab, Josiah, Seitenzahl, Ivo, Shen, Ken, Siegert, Thomas, Sim, Stuart, Smith, David, Smith, Karl, Smith, Michael, Sollerman, Jesper, Sprouse, Trevor, Spyrou, Artemis, Starrfield, Sumner, Steiner, Andrew, Strong, Andrew W., Sukhbold, Tuguldur, Suntzeff, Nick, Surman, Rebecca, Tanimori, Toru, The, Lih-Sin, Thielemann, Friedrich-Karl, Tolstov, Alexey, Tominaga, Nozomu, Tomsick, John, Townsley, Dean, Tsintari, Pelagia, Tsygankov, Sergey, Vartanyan, David, Venters, Tonia, Vestrand, Tom, Vink, Jacco, Waldman, Roni, Wang, Lifang, Wang, Xilu, Warren, Mackenzie, West, Christopher, Craig Wheeler, J., Wiescher, Michael, Winkler, Christoph, Winter, Lisa, Wolf, Bill, Woolf, Richard, Woosley, Stan, Wu, Jin, Wrede, Chris, Yamada, Shoichi, Young, Patrick, Zegers, Remco, Zingale, Michael, Portegies Zwart, Simon, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), European Space Agency (ESA), HEP, INSPIRE, and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Cosmology and Extragalactic Astrophysics, [PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics::Galaxy Astrophysics
Abstract

Gamma-ray astronomy explores the most energetic photons in nature to address some of the most pressing puzzles in contemporary astrophysics. It encompasses a wide range of objects and phenomena: stars, supernovae, novae, neutron stars, stellar-mass black holes, nucleosynthesis, the interstellar medium, cosmic rays and relativistic-particle acceleration, and the evolution of galaxies. MeV gamma-rays provide a unique probe of nuclear processes in astronomy, directly measuring radioactive decay, nuclear de-excitation, and positron annihilation. The substantial information carried by gamma-ray photons allows us to see deeper into these objects, the bulk of the power is often emitted at gamma-ray energies, and radioactivity provides a natural physical clock that adds unique information. New science will be driven by time-domain population studies at gamma-ray energies. This science is enabled by next-generation gamma-ray instruments with one to two orders of magnitude better sensitivity, larger sky coverage, and faster cadence than all previous gamma-ray instruments. This transformative capability permits: (a) the accurate identification of the gamma-ray emitting objects and correlations with observations taken at other wavelengths and with other messengers; (b) construction of new gamma-ray maps of the Milky Way and other nearby galaxies where extended regions are distinguished from point sources; and (c) considerable serendipitous science of scarce events -- nearby neutron star mergers, for example. Advances in technology push the performance of new gamma-ray instruments to address a wide set of astrophysical questions.

Published
2019

7. HYPERNOVAE AND GAMMA-RAY BURSTS

Author

Nomoto, Kenʼichi, Maeda, Keiichi, Tominaga, Nozomu, Ohkubo, Takuya, Deng, Jinsong, and Mazzali, Paolo A.

Published
2005

14. Type II Supernovae as Probes of Cosmology

Author

Poznanski, Dovi, Baron, Eddie, Blondin, Stéphane, Bloom, Joshua S., D Andrea, Christopher, Della Valle, Massimo, Dessart, Luc, Ellis, Richard S., Gal-Yam, Avishay, Goobar, Ariel, Hamuy, Mario, Hicken, Malcolm, Kasen, Daniel N., Krisciunas, Kevin L., Leonard, Douglas C., Li, Weidong, Livio, Mario, Marion, Howie, Matheson, Thomas, Neill, James D., Nomoto, Ken Ichi, Nugent, Peter E., Quimby, Robert, Sako, Masao, Sullivan, Mark, Thomas, Rollin C., Turatto, Massimo, Schuyler Van Dyk, and Wood-Vasey, W. Michael

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), astro-ph.CO, Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Constraining the cosmological parameters and understanding Dark Energy have tremendous implications for the nature of the Universe and its physical laws. - The pervasive limit of systematic uncertainties reached by cosmography based on Cepheids and Type Ia supernovae (SNe Ia) warrants a search for complementary approaches. - Type II SNe have been shown to offer such a path. Their distances can be well constrained by luminosity-based or geometric methods. Competing, complementary, and concerted efforts are underway, to explore and exploit those objects that are extremely well matched to next generation facilities. Spectroscopic follow-up will be enabled by space- based and 20-40 meter class telescopes. - Some systematic uncertainties of Type II SNe, such as reddening by dust and metallicity effects, are bound to be different from those of SNe Ia. Their stellar progenitors are known, promising better leverage on cosmic evolution. In addition, their rate - which closely tracks the ongoing star formation rate - is expected to rise significantly with look- back time, ensuring an adequate supply of distant examples. - These data will competitively constrain the dark energy equation of state, allow the determination of the Hubble constant to 5%, and promote our understanding of the processes involved in the last dramatic phases of massive stellar evolution., Comment: Science white paper, submitted to the Decadal committee Astro2010

Published
2009
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16. Lenvatinib, an angiogenesis inhibitor targeting VEGFR/FGFR, shows broad antitumor activity in human tumor xenograft models associated with microvessel density and pericyte coverage

Author

Yamamoto, Yuji, primary, Matsui, Junji, additional, Matsushima, Tomohiro, additional, Obaishi, Hiroshi, additional, Miyazaki, Kazuki, additional, Nakamura, Katsuji, additional, Tohyama, Osamu, additional, Semba, Taro, additional, Yamaguchi, Atsumi, additional, Hoshi, Sachi, additional, Mimura, Fusayo, additional, Haneda, Toru, additional, Fukuda, Yoshio, additional, Kamata, Jun-ichi, additional, Takahashi, Keiko, additional, Matsukura, Masayuki, additional, Wakabayashi, Toshiaki, additional, Asada, Makoto, additional, Nomoto, Ken-ichi, additional, Watanabe, Tatsuo, additional, Dezso, Zoltan, additional, Yoshimatsu, Kentaro, additional, Funahashi, Yasuhiro, additional, and Tsuruoka, Akihiko, additional

Published
2014
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19. Keck and European Southern Observatory Very Large Telescope View of the Symmetry of the Ejecta of the XRF/SN 2006aj

Author

Mazzali, Paolo A., primary, Foley, Ryan J., additional, Deng, Jinsong, additional, Patat, Ferdinando, additional, Pian, Elena, additional, Baade, Dietrich, additional, Bloom, Joshua S., additional, Filippenko, Alexei V., additional, Perley, Daniel A., additional, Valenti, Stefano, additional, Wang, Lifan, additional, Kawabata, Koji, additional, Maeda, Keiichi, additional, and Nomoto, Ken‐ichi, additional

Published
2007
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26. Nucleosynthesis by Type Ia Supernova for different Metallicity.

Author

Ohkubo, Takuya, Umeda, Hideyuki, Nomoto, Ken';ichi, and Yoshida, Takashi

Subjects
COSMOCHEMISTRY, CHEMICAL elements, SPACE sciences, COSMIC abundances, INTERSTELLAR molecules
Abstract

We calculate nucleosynthesis by type Ia supernova for various metallicity. We adopt two typical hydrodynamical models, carbon deflagration and delayed detonation. The two main points of this research are to see that (1)how the ejected mass of 56Ni changes and (2)how abundance of each element (especially Fe-group elements) is influenced by varying metallicity. We find that (1)56Ni mass changes about 15% in the range of Z = 0.001 – 0.05 and insufficient to explain all of the observed variety of SNe Ia peak luminosity, and (2)[Mn/Fe] and [Ni/Fe] show fairy dependence on metallicity (especially for delayed detonation model) while [Cr/Fe] or [α/Fe] do not. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2006
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29. Tumor induction in mice administered neonatally with 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole or 3-amino-1-methyl-5H-pyrido[4,3-b]indole.

Author

Fujii, Keiji, Nomoto, Ken-ichi, and Nakamura, Kyoichi

Abstract

3-Amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) or 3-amino-1-methyl-5H-pyrido[4,3-b]mdole (Trp-P-2), which is a potent mutagen from pyrolysates of tyrptophan, was given subcutaneously to neonatal ICR mice, and all animals were observed for 1 year. Tumors of the livers and lympho-retkular tissue were induced. In the mice given Trp-P-1, the incidences of these tumors were as follows: liver tumors in 45% of the males; malignant lymphoma in 13% of the males and in 24% of the females. In the mice given Trp-P-2, the incidences of liver tumors in the males were dose-dependent (12.5 mg/kg, 12%; 25 mg/kg, 18%), while those of malignant lymphoma varied within a range from 5 to 19%. Statistical analysis revealed that the incidences of the liver tumor in the mke given Trp-P-1 or Trp-P-2 and those of lymphoma in the mice given Trp-P-1 were significantly higher than those of the controls. In the control mice, the incidences of tumors were as follows: malignant lymphoma in 5% of the females; lung tumor in 14% of both sexes. [ABSTRACT FROM PUBLISHER]

Published
1987

30. High-resolution optical studies of nearby Type Ia supernovae

Author

Lundqvist, Peter, Mattila, Seppo, Sollerman, Jesper, Baron, E., Ehrenfreund, Pascale, Fransson, Claes, Bruno Leibundgut, and Nomoto, Ken Ichi

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

Since April 2000, a program using the ESO/VLT/UVES to search for early circumstellar signatures from nearby supernovae has been conducted. Until now, two Type Ia supernovae have been observed, SNe 2000cx and 2001el. Here we report on preliminary results for SNe 2001el, and we discuss how the observations can be used together with detailed modeling to derive an upper limit on the putative wind from the progenitor system. For a hydrogen-rich wind with velocity 10 km/s, the mass loss rate for the progenitor system of SN 2001el is less than 1O^{-5} solar masses per year., Comment: 5 pages, 2 figures. To appear in Proceedings "Supernovae", IAU Colloquium 192, eds. J.M. Marcaide, K.W. Weiler

31. Formation of the Elements

Author

Hughes, John P., Badenes, Carlos, Bamba, Aya, Blair, William, Decourchelle, Anne, Dewey, Daniel, Fryer, Christopher, Hwang, Una, Laming, J. Martin, Nomoto, Ken Ichi, Park, Sangwook, Patnaude, Daniel, Plucinsky, Paul, Rudnick, Lawrence, Slane, Patrick, Friedrich-Karl Thielemann, Vink, Jacco, and Winkler, P. Frank

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