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18 results on '"M. Y. Kim"'

1. Measurements of Ω and Λ from 42 High‐Redshift Supernovae

Author

S. Perlmutter, G. Aldering, G. Goldhaber, R. A. Knop, P. Nugent, P. G. Castro, S. Deustua, S. Fabbro, A. Goobar, D. E. Groom, I. M. Hook, A. G. Kim, M. Y. Kim, J. C. Lee, N. J. Nunes, R. Pain, C. R. Pennypacker, R. Quimby, C. Lidman, R. S. Ellis, M. Irwin, R. G. McMahon, P. Ruiz‐Lapuente, N. Walton, B. Schaefer, B. J. Boyle, A. V. Filippenko, T. Matheson, A. S. Fruchter, N. Panagia, H. J. M. Newberg, W. J. Couch, and The Supernova Cosmology Project

Subjects
Physics, Age of the universe, Angular diameter distance, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Omega, Redshift, symbols.namesake, Supernova, 13. Climate action, Space and Planetary Science, symbols, Astrophysics::Solar and Stellar Astrophysics, Baryon acoustic oscillations, Supernova Legacy Survey, Astrophysics::Galaxy Astrophysics, Hubble's law
Abstract

We report measurements of the mass density, Omega_M, and cosmological-constant energy density, Omega_Lambda, of the universe based on the analysis of 42 Type Ia supernovae discovered by the Supernova Cosmology Project. The magnitude-redshift data for these SNe, at redshifts between 0.18 and 0.83, are fit jointly with a set of SNe from the Calan/Tololo Supernova Survey, at redshifts below 0.1, to yield values for the cosmological parameters. All SN peak magnitudes are standardized using a SN Ia lightcurve width-luminosity relation. The measurement yields a joint probability distribution of the cosmological parameters that is approximated by the relation 0.8 Omega_M - 0.6 Omega_Lambda ~= -0.2 +/- 0.1 in the region of interest (Omega_M 0) = 99%, including the identified systematic uncertainties. The best-fit age of the universe relative to the Hubble time is t_0 = 14.9{+1.4,-1.1} (0.63/h) Gyr for a flat cosmology. The size of our sample allows us to perform a variety of statistical tests to check for possible systematic errors and biases. We find no significant differences in either the host reddening distribution or Malmquist bias between the low-redshift Calan/Tololo sample and our high-redshift sample. The conclusions are robust whether or not a width-luminosity relation is used to standardize the SN peak magnitudes.

Published
1999
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2. Discovery of a supernova explosion at half the age of the Universe

Author

Nino Panagia, C. Lidman, Saul Perlmutter, Peter Nugent, D. E. Groom, Nicholas A. Walton, A. Goobar, R. G. McMahon, A. S. Fruchter, Greg Aldering, R. Pain, Susana E. Deustua, C. R. Pennypacker, G. Goldhaber, M. Della Valle, Sebastien Fabbro, B. E. Schaefer, R. A. Knop, M. Y. Kim, P. Ruiz-Lapuente, I. M. Hook, A. G. Kim, and Richard S. Ellis

Subjects
Physics, Multidisciplinary, Age of the universe, Deceleration parameter, 010308 nuclear & particles physics, Big Crunch, Ultimate fate of the universe, Astrophysics::High Energy Astrophysical Phenomena, media_common.quotation_subject, Astrophysics::Cosmology and Extragalactic Astrophysics, Cosmological constant, Astrophysics, 01 natural sciences, Redshift, Universe, Supernova, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, media_common
Abstract

The ultimate fate of the universe, infinite expansion or a big crunch, can be determined by measuring the redshifts, apparent brightnesses, and intrinsic luminosities of very distant supernovae. Recent developments have provided tools that make such a program practicable: (1) Studies of relatively nearby Type Ia supernovae (SNe Ia) have shown that their intrinsic luminosities can be accurately determined; (2) New research techniques have made it possible to schedule the discovery and follow-up observations of distant supernovae, producing well over 50 very distant (z = 0.3 -- 0.7) SNe Ia to date. These distant supernovae provide a record of changes in the expansion rate over the past several billion years. By making precise measurements of supernovae at still greater distances, and thus extending this expansion history back far enough in time, we can distinguish the slowing caused by the gravitational attraction of the universe's mass density Omega_M from the effect of a possibly inflationary pressure caused 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 Ia, 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.

Published
1998
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3. Measurements of the Cosmological Parameters Ω and Λ from the First Seven Supernovae atz≥ 0.35

Author

I. M. Hook, A. G. Kim, M. Y. Kim, Thomas Matheson, Alexei V. Filippenko, S. Gabi, A. Goobar, R. G. McMahon, C. R. Pennypacker, Michael A. Dopita, P. S. Bunclark, B. J. Boyle, Janice C. Lee, D. Carter, D. E. Groom, R. Pain, Heidi Jo Newberg, W. J. Couch, Karl Glazebrook, Richard S. Ellis, Saul Perlmutter, G. Goldhaber, Mike Irwin, and I. Small

Subjects
Physics, Deceleration parameter, 010308 nuclear & particles physics, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Cosmological constant, Astrophysics, Type (model theory), Lambda, 01 natural sciences, Omega, Redshift, symbols.namesake, Space and Planetary Science, 0103 physical sciences, symbols, Astrophysics::Solar and Stellar Astrophysics, High Energy Physics::Experiment, Supernova Legacy Survey, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Hubble's law
Abstract

We have developed a technique to systematically discover and study high-redshift supernovae that can be used to measure the cosmological parameters. We report here results based on the initial seven of >28 supernovae discovered to date in the high-redshift supernova search of the Supernova Cosmology Project. We find a dispersion in peak magnitudes of sigma_{M_B} = 0.27 this dispersion narrows to sigma_{M_B,corr} = 0.19 after "correcting" the magnitudes using the light-curve "width-luminosity" relation found for nearby (z

Published
1997
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4. Implications for the Hubble Constant from the First Seven Supernovae at [CLC][ITAL]z[/ITAL][/CLC] ≥ 0.35

Author

Alexei V. Filippenko, I. M. Hook, W. J. Couch, M. Y. Kim, R. Pain, Supernova Cosmology, Thomas Matheson, Saul Perlmutter, A. G. Kim, I. Small, S. Gabi, Richard S. Ellis, Mike Irwin, G. Goldhaber, Karl Glazebrook, A. Goobar, R. G. McMahon, Janice C. Lee, B. J. Boyle, D. E. Groom, D. Carter, C. R. Pennypacker, P. S. Bunclark, Heidi Jo Newberg, and Michael A. Dopita

Subjects
Physics, 010308 nuclear & particles physics, media_common.quotation_subject, Shape of the universe, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Lambda, Light curve, 01 natural sciences, Cosmology, Universe, symbols.namesake, Supernova, Space and Planetary Science, 0103 physical sciences, symbols, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, media_common, Hubble's law
Abstract

The Supernova Cosmology Project has discovered over twenty-eight supernovae (SNe) at 0.35 = 0.2, we find that H_0^G < 70 km/s/Mpc in a Lambda=0 universe and H_0^G < 78 km/s/Mpc in a flat universe, correcting the distant and local SN apparent magnitudes for light curve width. Lower results for H_0^G are obtained if the magnitudes are not width corrected.

Published
1997
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5. High-redshift supernova discoveries on demand: First results from a new tool for cosmology and bounds on q0

Author

B. J. Boyle, Susana E. Deustua, Richard S. Ellis, Warrick J. Couch, A. G. Kim, M. Y. Kim, Alexei V. Filippenko, Gerson Goldhaber, I. M. Hook, Thomas Matheson, Ariel Goobar, Karl Glazebrook, Julia C. Lee, D. Carter, Donald E. Groom, Saul Perlmutter, C. R. Pennypacker, P. S. Bunclark, Richard G. McMahon, Heidi Jo Newberg, S. Gabi, Michael A. Dopita, Mike Irwin, R. Pain, and I. A. Small

Subjects
Physics, Nuclear and High Energy Physics, Field (physics), Calibration (statistics), Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Light curve, Atomic and Molecular Physics, and Optics, Redshift, Cosmology, Spectral line, Supernova, Measurement uncertainty
Abstract

We have developed a new tool for measurement of the cosmological parameters: a systematic search-and-study technique for high-redshift supernovae. In the first years of this Supernova Cosmology Project, we have discovered over 27 supernovae. Using a “batch” search strategy, almost all were discovered before maximum light and were observed over the peak of their light curves. The spectra and light curves indicate that almost all were Type Ia supernovae at redshifts z = 0.35 – 0.65. These high-redshift supernovae can provide a distance indicator and “standard clock” to study the cosmological parameters q 0 , Λ, Ω 0 , and H 0 . This presentation and the following presentation of Goldhaber et al . (1996), will discuss observation strategies and rates, analysis and calibration issues, the sources of measurement uncertainty, and the cosmological implications, including bounds on q 0 , of the first 7 high-redshift supernovae from our ongoing search. This is one of the most direct approaches to cosmological measurements, and could become a standard method in the field.

Published
1996
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6. The distant supernova search and implications for the cosmological deceleration

Author

B. J. Boyle, M. Y. Kim, Saul Perlmutter, S. Gabi, G. Goldhaber, R. Pain, Richard S. Ellis, Richard G. McMahon, Richard A. Muller, D. Carter, A. G. Kim, I. A. Small, Mike Irwin, C. R. Pennypacker, P. S. Bunclark, and A. Goobar

Subjects
Physics, Absolute magnitude, Nuclear and High Energy Physics, Observational error, Deceleration parameter, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Atomic and Molecular Physics, and Optics, Galaxy, Redshift, Photometry (optics), Supernova, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Spectroscopy, Astrophysics::Galaxy Astrophysics
Abstract

We have begun a program to discover high-redshift supernovae ( z ≈ 0.2–0.6), and study them with follow-up photometry and spectroscopy. We report here our first discovery, a supernova at z = 0.458 (SN1992bi) and the ongoing analysis on several new supernova candidates found in a recent search (Dec 93 – March 94). The photometry for SN1992bi closely matches the lightcurve calculated for its redshift from the template of well-observed nearby Type la supernovae giving a best fit value for the deceleration parameter: q o = 0.1 ± 0.3 (±0.55) (with Λ = 0), where the first uncertainty is due to the photometry of the distant supernova and the second reflects the estimated intrinsic width of the Type la absolute magnitude distribution based on nearby supernovae. If there is significant host galaxy extinction then q o would be larger than this best fit value. We describe the main sources of measurement error inherent in such a measurement of qo , and ways to reduce these errors.

Published
1995
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7. Discovery of the most distant supernovae and the quest for Ω

Author

Gerson Goldhaber, Reynald Pain, Silvia Gabi, C. R. Pennypacker, P. S. Bunclark, Richard G. McMahon, D. Carter, Richard S. Ellis, A. Goobar, M. Y. Kim, Alex G. Kim, Roberto Terlevich, Saul Perlmutter, I. Small, and B. J. Boyle

Subjects
Physics, Nuclear and High Energy Physics, Deceleration parameter, Astrophysics::High Energy Astrophysical Phenomena, media_common.quotation_subject, Cosmic distance ladder, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Type (model theory), Omega, Atomic and Molecular Physics, and Optics, Universe, Cosmology, Metric expansion of space, Supernova, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Galaxy Astrophysics, media_common
Abstract

A search for cosmological supernovae has discovered a number of a type la supernovae. In particular, one at z = 0.458 is the most distant supernova yet observed. There is strong evidence from measurements of nearby type Ia supernovae that they can be considered as 'standard candles'. We plan to use these supernovae to measure the deceleration in the general expansion of the universe. The aim of our experiment is to try and observe and measure about 30 such distant supernovae in order to obtain a measurement of the deceleration parameter q{sub 0} which is related to {Omega}. Here {Omega} is the ratio of the density of the universe to the critical density, and we expect a measurement with an accuracy of about 30%.

Published
1995
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8. A Supernova at z = 0.458 and Cosmologya

Author

Richard A. Muller, Richard G. McMahon, G. Goldhaber, B. J. Boyle, M. Y. Kim, R. Abraham, C. S. Crawford, M. Irwin, J. Desai, Warrick J. Couch, D. Carter, A. G. Kim, Todd Small, A. Goobar, C. R. Pennypacker, P. S. Bunclark, I. A. Small, Jeremy Mould, Richard S. Ellis, H. J. M. Newberg, Karl Glazebrook, Roberto Terlevich, and Saul Perlmutter

Subjects
Physics, Supernova, History and Philosophy of Science, General Neuroscience, Astrophysics, General Biochemistry, Genetics and Molecular Biology
Published
1993
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9. Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01

Author

Aguilar, M, Alcaraz, J, Allaby, J, Alpat, B, Ambrosi, G, Anderhub, H, L. Ao, A. Arefiev, P. Azzarello, L. Baldini, M. Basile, D. Barancourt, F. Barao, G. Barbier, G. Barreira, R. Battiston, R. Becker, U. Becker, L. Bellagamba, P. Béné, J. Berdugo, P. Berges, B. Bertucci, A. Biland, S. Blasko, Boschini, M, M. Bourquin, L. Brocco, G. Bruni, M. Buénerd, J. D. Burger, W. J. Burger, X. D. Cai, C. Camps, P. Cannarsa, M. Capell, F. Cardano, D. Casadei, J. Casaus, G. Castellini, Y. H. Chang, H. F. Chen, H. S. Chen, Z. G. Chen, N. A. Chernoplekov, T. H. Chiueh, K. Cho, M. J. Choi, Y. Y. Choi, F. Cindolo, V. Commichau, A. Contin, E. Cortina Gil, M. Cristinziani, T. S. Dai, C. Delgado, S. Difalco, L. Djambazov, I. D'Antone, Z. R. Dong, P. Emonet, J. Engelberg, F. J. Eppling, T. Eronen, G. Esposito, P. Extermann, J. Favier, E. Fiandrini, P. H. Fisher, G. Flügge, N. Fouque, Y.u. Galaktionov, H. Gast, P. Giusti, Grandi, D, O. Grimm, W. Q. Gu, K. Hangarter, A. Hasan, V. Hermel, H. Hofer, W. Hungerford, M. Jongmanns, K. Karlamaa, W. Karpinski, G. Kenney, D. H. Kim, G. N. Kim, K. S. Kim, M. Y. Kim, A. Klimentov, R. Kossakowskic, A. Kouninel, V. Koutsenkol, M. Kraeberai, G. Laboriet, T. Laitinenah, G. Lamannaad, 1, E. Lanciottiz, G. Laurentij, A. Lebedevl, C. Lechanoine Lelucs, M. W. Leeo, S. C. Leeag, G. Levij, C. L. Liuy, H. T. Liui, G. Lug, Y. S. Lui, K. Lübelsmeyera, D. Luckeyl, W. Lustermannai, C. Mañaz, A. Margottij, F. Mayett, R. R. McNeild, B. Meillont, M. Menichelliad, A. Mihulk, A. Mujunenv, A. Olivaad, J. Olzema, F. Palmonarij, H. B. Parko, W. H. Parko, M. Pauluzziad, F. Paussai, E. Perrins, A. Pescij, A. Pevsnere, F. Piloae, M. Pimentax, w, V. Plyaskinac, V. Pojidaevac, M. Pohls, N. Produits, Rancoita, PG D. Rapins, F. Raupacha, D. Renai, Z. Renag, M. Ribordys, J. P. Richeuxs, E. Riihonenah, J. Ritakariv, S. Roo, U. Roeserai, C. Rossint, R. Sagdeevn, D. Santost, G. Sartorellij, C. Sbarraj, S. Schaela, A. Schultz von Dratziga, G. Schweringa, E. S. Seon, J. W. Shino, E. Shoumilovac, V. Shoutkol, T. Siedenburgl, R. Siedlinga, D. Sono, T. Songh, F. Spinellaae, M. Steuerl, G. S. Sunh, H. Suterai, X. W. Tangi, Samuel C. C. Tingl, S. M. Tingl, M. Tornikoskiv, J. Torstiah, J. Trümperq, J. Ulbrichtai, S. Urpov, E. Valtonenah, J. Vandenhirtza, E. Velikhovab, B. Verlaatai, 2, I. Vetlitskyac, F. Vezzut, J. P. Viallec, G. Viertelai, D. Vités, H. Von Guntenai, S. Waldmeier Wickiai, W. Wallraffa, B. C. Wangy, J. Z. Wangg, K. Wiikv, C. Williamsj, S. X. Wul, m, P. C. Xiah, S. Xul, J. L. Yang, L. G. Yanh, C. G. Yangi, J. Yangaf, M. Yangi, S. W. Yeu, 3, Z. Z. Xu, H. Y. Zhang, Z. P. Zhang, D. X. Zhao, Y. Zhou, G. Y. Zhu, W. Z. Zhu, H. L. Zhuang, A. Zichichi, B. Zimmermann, P. Zuccon, BOELLA, GIULIANO FILIPPO, GERVASI, MASSIMO, Bene, Pierre, Bourquin, Maurice, Cortina Gil, Eduardo, Cristinziani, Markus, Emonet, Pascal Philippe, Extermann, Pierre, Leluc, Catherine, Perrin, Eric, Pohl, Martin, Produit, Nicolas, Rapin, Divic Jean, Ribordy, Mathieu, Richeux, Jean-Pierre, Vite, Davide, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AMS, M. AGUILAR, J. ALCARAZ, J. ALLABY, B. ALPAT, G. AMBROSI, H. ANDERHUB, L. AO, A. AREFIEV, P. AZZARELLO, L. BALDINI, M. BASILE, D. BARANCOURT, F. BARAO, G. BARBIER, G. BARREIRA, R. BATTISTON, R. BECKER, U. BECKER, L. BELLAGAMBA, P. BENE, J. BERDUGO, P. BERGES, B. BERTUCCI, A. BILAND, S. BLASKO, G. BOELLA, M. BOSCHINI, M. BOURQUIN, L. BROCCO, G. BRUNI, M. BUENERD, J.D. BURGER, W.J. BURGER, X.D. CAI, C. CAMPS, P. CANNARSA, M. CAPELL, F. CARDANO, D. CASADEI, J. CASAUS, G. CASTELLINI, Y.H. CHANG, H.F. CHEN, H.S. CHEN, Z.G. CHEN, N.A. CHERNOPLEKOV, T.H. CHIUEH, K. CHO, M.J. CHOI, Y.Y. CHOI, F. CINDOLO, V. COMMICHAU, A. CONTIN, E. CORTINA-GIL, M. CRISTINZIANI, T.S. DAI, C. DELGADO, S. DIFALCO, L. DJAMBAZOV, I. D'ANTONE, Z.R. DONG, P. EMONET, J. ENGELBERG, F.J. EPPLING, T. ERONEN, G. ESPOSITO, P. EXTERMANN, J. FAVIER, E. FIANDRINI, P.H. FISHER, G. FLUEGGE, N. FOUQUE, YU. GALAKTIONOV, H. GAST, M. GERVASI, P. GIUSTI, D. GRANDI, O. GRIMM, W.Q. GU, K. HANGARTER, A. HASAN, V. HERMEL, H. HOFER, W. HUNGERFORD, M. JONGMANNS, K. KARLAMAA, W. KARPINSKI, G. KENNEY, D.H. KIM, G.N. KIM, K.S. KIM, M.Y. KIM, A. KLIMENTOV, R. KOSSAKOWSKI, A. KOUNINE, V. KOUTSENKO, M. KRAEBER, G. LABORIE, T. LAITINEN, G. LAMANNA, E. LANCIOTTI, G. LAURENTI, A. LEBEDEV, C. LECHANOINE-LELUC, M.W.LEE, S.C. LEE, G. LEVI, C.L. LIU, H.T. LIU, G. LU, Y.S. LU, K. LUBELSMEYER, D. LUCKEY, W. LUSTERMANN, C. MANA, A. MARGOTTI, F. MAYET, R.R. MCNEIL, B. MEILLON, M. MENICHELLI, A.MIHUL, A. MUJUNEN, A. OLIVA, J. OLZEM, F. PALMONARI, H.B. PARK, W.H. PARK, M. PAULUZZI, F. PAUSS, E. PERRIN, A. PESCI, A. PEVSNER, F. PILO, M. PIMENTA, V. PLYASKIN, V. POJIDAEV, M. POHL, N. PRODUIT, P.G. RANCOITA, D. RAPIN, F. RAUPACH, D. REN, Z. REN, M. RIBORDY, J.P. RICHEAUX, E. RIIHONEN, J. RITAKARI, S. RO, U. ROESER, C. ROSSIN, R. SAGDEEV, D. SANTOS, G. SARTORELLI, C. SBARRA, S. SCHAEL, A. SCHULTZ VON DRATZIG, G. SCHWERING, E.S. SEO, J.W. SHIN, E. SHOUMILOV, V. SHOUTKO, T. SIEDENBURG, R. SIEDLING, D. SON, T. SONG, F. SPINELLA, M. STEUER, G. S. SUN, H. SUTER, X.W. TANG, SAMUEL C.C. TING, S.M. TING, M. TORNIKOSKI, J. TORSTI, J. TRUEMPER, J. ULBRICHT, S. URPO, E. VALTONEN, J. VANDENHIRTZ, E. VELIKHOV, B. VERLAAT, I. VETLITSKI, F. VEZZU, J.P. VIALLE, G. VIERTEL, D. VITE, H. VON GUNTEN, S. WALDMEIER WICKI, W. WALLRAFF, B.C. WANG, J.Z. WANG, K. WIIK, C. WILLIAMS, S.X. WU, P.C. XIA, S. XU, J.L. YAN, L.G. YAN, C.G. YANG, J. YANG, M. YANG, S.W. YE, Z.Z. XU, H.Y. ZHANG, Z.P. ZHANG, D.X. ZHAO, Y. ZHOU, G.Y.ZHU, W.Z. ZHU, H.L. ZHUANG, A. ZICHICHI, B. ZIMMERMANN, P. ZUCCON, Aguilar, M, Alcaraz, J, Allaby, J, Alpat, B, Ambrosi, G, Anderhub, H, L., A, A., A, P., A, L., B, M., B, D., B, F., B, G., B, R., B, U., B, P., B, J., B, B., B, A., B, S., B, Boella, G, Boschini, M, J. D., B, W. J., B, X. D., C, C., C, P., C, M., C, F., C, D., C, J., C, G., C, Y. H., C, H. F., C, H. S., C, Z. G., C, N. A., C, T. H., C, K., C, M. J., C, Y. Y., C, V., C, A., C, E., C, T. S., D, C., D, S., D, L., D, I., D, Z. R., D, P., E, J., E, F. J., E, T., E, G., E, J., F, E., F, P. H., F, G., F, N., F, Galaktionov, Y, H., G, Gervasi, M, P., G, Grandi, D, O., G, W. Q., G, K., H, A., H, V., H, H., H, W., H, M., J, K., K, W., K, G., K, D. H., K, G. N., K, K. S., K, M. Y., K, A., K, R., K, V., K, Ac, M., K, G., L, T., L, E., L, A., L, C., L, M. W., L, S. C., L, C. L., L, H. T., L, Y. S., L, K., L, D., L, W., L, C., M, A., M, F., M, R. R., M, B., M, M., M, A., O, J., O, F., P, H. B., P, W. H., P, M., P, E., P, A., P, W, V., P, N., P, Rancoita, PG D., R, F., R, D., R, Z., R, M., R, J. P., R, E., R, J., R, S., R, U., R, C., R, R., S, D., S, G., S, C., S, S., S, A., S, E. S., S, J. W., S, E., S, V., S, T., S, F., S, M., S, G. S., S, H., S, X. W., T, Samuel C. C., T, S. M., T, M., T, J., T, J., U, S., U, E., V, J., V, B., V, I., V, F., V, J. P., V, G., V, D., V, H., V, S., W, W., W, B. C., W, J. Z., W, K., W, C., W, S. X., W, M, P. C., X, S., X, J. L., Y, L. G., Y, C. G., Y, J., Y, M., Y, S. W., Y, Z. Z., X, H. Y., Z, Z. P., Z, D. X., Z, Y., Z, G. Y., Z, W. Z., Z, H. L., Z, A., Z, B., Z, P., Z, and UCL - SST/IRMP - Institut de recherche en mathématique et physique

Subjects
Raggi cosmici, esperimento AMS, Nuclear and High Energy Physics, Astrophysics and Astronomy, Photon, Proton, Astrophysics::High Energy Astrophysical Phenomena, Cosmic ray, ddc:500.2, Astrophysics, 01 natural sciences, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Nuclear physics, FIS/05 - ASTRONOMIA E ASTROFISICA, Positron, 0103 physical sciences, 010306 general physics, Nuclear Experiment, Physics, Range (particle radiation), 010308 nuclear & particles physics, Bremsstrahlung, Order (ring theory), Cosmic Rays Positrons, AMS experiment, Physics::Accelerator Physics, FIS/04 - FISICA NUCLEARE E SUBNUCLEARE, Energy (signal processing)
Abstract

A measurement of the cosmic ray positron fraction e+ / (e+ + e-) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 106 is reached by identifying converted bremsstrahlung photons emitted from positrons., Physics Letters B, 646 (4), ISSN:0370-2693, ISSN:0031-9163, ISSN:1873-2445

Published
2007
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10. The distant type Ia supernova rate

Author

I. M. Hook, A. Goobar, Greg Aldering, C. R. Pennypacker, D. Hardin, Sebastien Fabbro, Mike Irwin, Pierre Astier, C. Lidman, A. G. Kim, Peter Nugent, K. Schahmaneche, Saul Perlmutter, Richard G. McMahon, S. E. Duestua, D. A. Howell, Nino Panagia, Mark Sullivan, P. Ruiz-Lapuente, G. Goldhaber, Nicholas A. Walton, D. E. Groom, M. Y. Kim, Reynald Pain, A. S. Fruchter, Julia C. Lee, R. A. Knop, Richard S. Ellis, B. E. Schaefer, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), SUPERNOVAE, and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC)

Subjects
010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Context (language use), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Type (model theory), Astronomy & Astrophysics, 01 natural sciences, Atomic, Physical Chemistry, Square (algebra), Cosmology, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Particle and Plasma Physics, astro-ph, 0103 physical sciences, Nuclear, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, evolution [galaxies], 0105 earth and related environmental sciences, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Star formation, Astrophysics (astro-ph), Molecular, Astronomy and Astrophysics, Cosmological model, Redshift, Supernova, Space and Planetary Science, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, general [supernovae], high-redshift [galaxies], Astronomical and Space Sciences, Physical Chemistry (incl. Structural)
Abstract

We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially-flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean redshift $z\simeq0.55$ of $1.53 {^{+0.28}_{-0.25}} {^{+0.32}_{-0.31}} 10^{-4} h^3 {\rm Mpc}^{-3} {\rm yr}^{-1}$ or $0.58 {^{+0.10}_{-0.09}} {^{+0.10}_{-0.09}} h^2 {\rm SNu}$ (1 SNu = 1 supernova per century per $10^{10}$\Lbsun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models., Comment: 40 pages and 7 figures. Accepted for publication in the Astrophysical Journal. Preprint also available at http://supernova.lbl.gov

Published
2002
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11. The Acceleration of the Universe: Measurements of Cosmological Parameters from Type Ia Supernovae

Author

A. G. Kim, Donald E. Groom, A. V. Filippenko, Peter Nugent, W. J. Couch, A. S. Fruchter, Bradley E. Schaefer, Richard S. Ellis, Robert Quimby, Nino Panagia, Saul Perlmutter, B. J. Boyle, Thomas Matheson, R. A. Knop, Christopher Lidman, G. Goldhaber, Heidi Jo Newberg, Pilar Ruiz-Lapuente, Greg Aldering, Susana E. Deustua, I. M. Hook, C. R. Pennypacker, M. Y. Kim, Mike Irwin, Ariel Goobar, P. G. Castro, Sebastien Fabbro, Nelson J. Nunes, Julia C. Lee, R. Pain, Nicholas A. Walton, and Richard G. McMahon

Subjects
Physics, Age of the universe, Astronomy, Big Rip, Non-standard cosmology, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Cosmological constant, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Metric expansion of space, symbols.namesake, De Sitter universe, symbols, Flatness problem, Astrophysics::Galaxy Astrophysics, Mathematical Physics, Hubble's law
Abstract

The fate of the Universe, infinite expansion or a ldquo;big crunchrdquo;, can be determined by measuring the redshifts and brightness of very distant supernovae. These provide a record of changes in the expansion rate of the Universe over the past several billion years. The mass density, ?M, and cosmological-constant energy density ??, are measured from a data-set consisting of 42 high-redshift Type Ia supernovae discovered by the Supernova Cosmology Project. The magnitude-redshift data for these supernovae, at redshifts between 0.18 and 0.83, are fit jointly with a set of supernovae from the Cal?n/Tololo Supernova Survey, at redshifts below 0.1, to yield values for the cosmological parameters. We find ?Mflat = 0.28+0.09-0.08 (1? statistical)+0.05-0.04 (identified systematics). The data are strongly inconsistent with a ? = 0 flat cosmology, the simplest inflationary universe model. An open, ? = 0 cosmology also does not fit the data well: the data indicate that the cosmological constant is non-zero and positive, with a confidence of P(?>0) = 99%, including the identified systematic uncertainties. Thus, the Universe is found to be accelerating, i.e., q0 = ?M/2 - ?? < 0. The best-fit age of the universe relative to the Hubble time is t0flat = 14.9+1.4-1.1 (0.63/h) Gyr for a flat cosmology.

Published
2001
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12. Timescale Stretch Parameterization of Type Ia Supernova B-band Light Curves

Author

Pierre Astier, Susana E. Deustua, Reynald Pain, Sebastien Fabbro, R. A. Knop, Supernova Cosmology, Michael G. Irwin, Richard Ellis, M. Y. Kim, G. Goldhaber, Greg Aldering, T. York, Peter Nugent, I. M. Hook, C. R. Pennypacker, B. E. Schaefer, C. Lidman, D. E. Groom, A. G. Kim, A. S. Fruchter, Alex Conley, Saul Perlmutter, Ariel Goobar, P. Ruiz-Lapuente, Nicholas A. Walton, Richard G. McMahon, Nino Panagia, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), SUPERNOVAE, and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Brightness, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics Cosmology Supernovae, Light curve, 01 natural sciences, Redshift, Photometry (optics), [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Stretch factor, Supernova, Space and Planetary Science, 0103 physical sciences, Tired light, Supernova Legacy Survey, 010303 astronomy & astrophysics
Abstract

R-band intensity measurements along the light curve of Type Ia supernovae discovered by the Supernova Cosmology Project (SCP) are fitted in brightness to templates allowing a free parameter the time-axis width factor w = s(1+z). The data points are then individually aligned in the time-axis, normalized and K-corrected back to the rest frame, after which the nearly 1300 normalized intensity measurements are found to lie on a well-determined common rest-frame B-band curve which we call the ``composite curve''. The same procedure is applied to 18 low-redshift Calan/Tololo SNe with z < 0.11; these nearly 300 B-band photometry points are found to lie on the composite curve equally well. The SCP search technique produces several measurements before maximum light for each supernova. We demonstrate that the linear stretch factor, s, which parameterizes the light-curve timescale appears independent of z,and applies equally well to the declining and rising parts of the light curve. In fact, the B-band template that best fits this composite curve fits the individual supernova photometry data when stretched by a factor s with chi^2/DoF approx = 1, thus as well as any parameterization can, given the current data sets. The measurement of the date of explosion, however, is model dependent and not tightly constrained by the current data. We also demonstrate the 1+z light-curve time-axis broadening expected from cosmological expansion. This argues strongly against alternative explanations, such as tired light, for the redshift of distant objects., 27 pages,3 figures, accepted by ApJ

Published
2001
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13. Scheduled Discoveries of 7+ High-Redshift Supernovae:First Cosmology Results and Bounds on q 0

Author

C. R. Pennypacker, P. S. Bunclark, Richard G. McMahon, Heidi Jo Newberg, I. A. Small, Susana E. Deustua, G. Goldhaber, M. Y. Kim, Karl Glazebrook, Saul Perlmutter, Donald E. Groom, R. Pain, Alexei V. Filippenko, A. G. Kim, Ariel Goobar, S. Gabi, Michael A. Dopita, D. Carter, B. J. Boyle, Richard S. Ellis, Thomas Matheson, Warrick J. Couch, I. M. Hook, M. Irwin, Julia C. Lee, and Jeremy Mould

Subjects
Physics, Supernova, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Type (model theory), Light curve, Lambda, Omega, Astronomical spectroscopy, Cosmology, Redshift
Abstract

Our search for high-redshift Type Ia supernovae discovered, in its first years, a sample of seven supernovae. Using a ``batch`` search strategy, almost all were discovered before maximum light and were observed over the peak of their light curves. The spectra and light curves indicate that almost all were Type Ia supernovae at redshifts z = 0.35 - 0.5. These high-redshift supernovae can provide a distance indicator and ``standard clock`` to study the cosmological parameters q{sub 0} , {Lambda}, {Omega}{sub 0} , and H{sub 0}. This presentation and the following presentations of Kim et al. (1996), Goldhaber et al. (1996), and Pain et al. (1996) will discuss observation strategies and rates, analysis and calibration issues, the sources of measurement uncertainty, and the cosmological implications, including bounds on q{sub 0} , of these first high-redshift supernovae from our ongoing search.

Published
1997
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14. The Type Ia Supernova Rate at z ~ 0.4

Author

Susana E. Deustua, Michael G. Irwin, I. Small, G. Goldhaber, Karl Glazebrook, I. M. Hook, Saul Perlmutter, D. Carter, R. Pain, D. E. Groom, S. Gabi, Janice C. Lee, Richard Ellis, B. J. Boyle, A. Kim, M. Y. Kim, A. Goobar, R. G. McMahon, C. R. Pennypacker, and P. S. Bunclark

Subjects
Physics, Astrophysics, Type (model theory)
Published
1997
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15. Observation of Cosmological Time Dilation Using Type Ia Supernovae as Clocks

Author

Warrick J. Couch, D. Carter, A. V. Filippenko, C. R. Pennypacker, P. S. Bunclark, I. M. Hook, Richard G. McMahon, B. J. Boyle, Karl Glazebrook, Michael A. Dopita, G. Goldhaber, I. A. Small, Jeremy Mould, S. Gabi, R. Pain, S. Perlmutter, Thomas Matheson, M. Y. Kim, Ariel Goobar, Heidi Jo Newberg, Susana E. Deustua, Julia C. Lee, Richard S. Ellis, Michael G. Irwin, Donald E. Groom, A. G. Kim, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Ruiz-Lapuente P., Canal R., Isern J., SUPERNOVAE, and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Type (model theory), Light curve, 01 natural sciences, Redshift, Spectral line, Metric expansion of space, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Supernova, 0103 physical sciences, Homogeneous group, Astrophysics::Solar and Stellar Astrophysics, Time dilation, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences
Abstract

This work is based on the first results from a systematic search for high redshift Type Ia supernovae. Using filters in the R-band we discovered seven such SNe, with redshift z = 0.3 - 0.5, before or at maximum light. Type Ia SNe are known to be a homogeneous group of SNe, to first order, with very similar light curves, spectra and peak luminosities. In this talk we report that the light curves we observe are all broadened (time dilated) as expected from the expanding universe hypothesis. Small variations from the expected 1+z broadening of the light curve widths can be attributed to a width-brightness correlation that has been observed for nearby SNe (z, 8 pages, 3 Postscript figures, uuencoded uses crckapb.sty and psfig.sty. To appear in Thermonuclear Supernovae (NATO ASI), eds. R. Canal, P. Ruiz-LaPuente, and J. Isern. Postscript version is also available at http://www-supernova.lbl.gov/

Published
1997
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16. A Supernova at z = 0.458 and Implications for Measuring the Cosmological Deceleration

Author

Jigna Desai, Richard A. Muller, Saul Perlmutter, Dave Carter, Richard G. McMahon, Warrick J. Couch, C. R. Pennypacker, Gerson Goldhaber, Karl Glazebrook, I. A. Small, Roberto Terlevich, Roberto Abraham, Ariel Goobar, M. Y. Kim, A. G. Kim, B. J. Boyle, Rowan Ellis, C. S. Crawford, H. J. M. Newberg, P. S. Bunclark, Todd Small, Mike Irwin, and Jeremy Mould

Subjects
Physics, Deceleration parameter, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Redshift, Photometry (astronomy), Supernova, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Sources of error, Astrophysics::Galaxy Astrophysics
Abstract

We have begun a program to discover high-redshift supernovae ($z \approx$ 0.25--0.5), and study them with follow-up photometry and spectroscopy. We report here our first discovery, a supernova at $z = 0.458$. The photometry for this supernova closely matches the lightcurve calculated for this redshift from the template of well-observed nearby Type Ia supernovae. We discuss the measurement of the deceleration parameter $q_0$ using such high-redshift supernovae, and give the best fit value assuming this one supernova is a normal, unextincted Type Ia. We describe the main sources of error in such a measurement of $q_0$, and ways to reduce these errors., Comment: Latex using aasms.sty and three postcript files uuencoded compressed. Ap.J.Lett., 440:L41, 1995 (posted for easy access). Complete postscript version also available at http://www-supernova.lbl.gov/public/index.html

Published
1995
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17. Erratum: Discovery of a supernova explosion at half the age of the Universe

Author

A. S. Fruchter, Sebastien Fabbro, M. Y. Kim, R. A. Knop, Susana E. Deustua, Richard S. Ellis, Nino Panagia, Saul Perlmutter, I. M. Hook, M. Della Valle, Peter Nugent, P. Ruiz-Lapuente, Nicholas A. Walton, A. G. Kim, R. Pain, C. Lidman, B. E. Schaefer, D. E. Groom, G. Goldhaber, A. Goobar, R. G. McMahon, Greg Aldering, and C. R. Pennypacker

Subjects
Physics, Supernova, Multidisciplinary, Age of the universe, Astronomy, Astrophysics
Abstract

Nature 391, 51– 54 (1998) The name of one of the authors (Ariel Goobar) of this Letter was inadvertently removed during page make-up. A. Goobar is in the Physics Department, Stockholm University, as indicated in the footnote addresses.

Published
1998
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18. The CALET space observatory for JEM-EF on the international space station

Author

John Mitchell, A. Shiomi, J. Yan, Tadashi Kobayashi, Shuichi Kuramata, M. Tkayanagi, Toshio Terasawa, P. Papini, Yoshiki Tsunesada, E. Vannuccini, K. Batkov, K. Hibino, K. Kasahara, Hiroyuki Murakami, Osamu Okudaira, N. Tateyama, M. Shibata, Jun Nishimura, S. Kodaira, M. Y. Kim, Weiqun Gan, A. A. MOlSEEV, Y. Katayose, H. Wang, Naoyuki Yamashita, J. P. Wefel, O. Adriani, Vincenzo Millucci, T. G. Guzik, P. Masestro, Shoji Torii, Gary L. Case, M. Miyazima, T. Tamura, M. H. Israel, John Krizmanic, T. Miyaji, J. Chang, Y. Komor, Masato Takita, Gabriele Bigongiari, A. Yoshida, J. F. Ormes, T. Yuda, Kenji Yoshida, P. S. Marrocchesi, Lorenzo Bonechi, Fumio Kakimoto, Y. Ma, S. Okuno, Takamasa Yamagami, Joachim Isbert, Kazuoki Munakata, Y. Uchihori, M. Ichimura, Shinji Ueno, Nobuyuki Hasebe, Henric Krawczynski, Riccardo Zei, Makoto Hareyama, Michael Cherry, G. Chen, Kazutaka Yamaoka, H. Tomida, H. Fuke, A. Kitamura, Maria Grazia Bagliesi, K. MIZUTANl, L. M. BARBlER, Yoshitaka Saito, W. R. Binns, Robert E. Streitmatter, and Y. Shimizu

Subjects
Physics, Gamma Rays, International Space Station, Dark matter, Gamma ray, Astronomy, Cosmic Ray Sources, Dark Matter, Electrons, Astrophysics, Space Station, Space observatory

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