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1,428 results on '"Ozaki, M"'

1. In-orbit performance of the soft X-ray imaging system aboard Hitomi (ASTRO-H)

Author

Nakajima, H., Maeda, Y., Uchida, H., Tanaka, T., Tsunemi, H., Hayashida, K., Tsuru, T. G., Dotani, T., Nagino, R., Inoue, S., Ozaki, M., Tomida, H., Natsukari, C., Ueda, S., Mori, K., Yamauchi, M., Hatsukade, I., Nishioka, Y., Sakata, M., Beppu, T., Honda, D., Nobukawa, M., Hiraga, J. S., Kohmura, T., Murakami, H., Nobukawa, K. K., Bamba, A., Doty, J. P., Iizuka, R., Sato, T., Kurashima, S., Nakaniwa, N., Asai, R., Ishida, M., Mori, H., Soong, Y., Okajima, T., Serlemitsos, P., Tawara, Y., Mitsuishi, I., Ishibashi, K., Tamura, K., Hayashi, T., Furuzawa, A., Sugita, S., Miyazawa, T., Awaki, H., Miller, E. D., and Yamaguchi, H.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

We describe the in-orbit performance of the soft X-ray imaging system consisting of the Soft X-ray Telescope and the Soft X-ray Imager aboard Hitomi. Verification and calibration of imaging and spectroscopic performance are carried out making the best use of the limited data of less than three weeks. Basic performance including a large field of view of 38'x38' is verified with the first light image of the Perseus cluster of galaxies. Amongst the small number of observed targets, the on-minus-off pulse image for the out-of-time events of the Crab pulsar enables us to measure a half power diameter of the telescope as about 1.3'. The average energy resolution measured with the onboard calibration source events at 5.89 keV is 179 pm 3 eV in full width at half maximum. Light leak and cross talk issues affected the effective exposure time and the effective area, respectively, because all the observations were performed before optimizing an observation schedule and parameters for the dark level calculation. Screening the data affected by these two issues, we measure the background level to be 5.6x10^{-6} counts s^{-1} arcmin^{-2} cm^{-2} in the energy band of 5-12 keV, which is seven times lower than that of the Suzaku XIS-BI., Comment: Accepted for publication in PASJ. 17 pages, 18 figures

Published
2017
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3. ASTRO-H White Paper - Older Supernova Remnants and Pulsar Wind Nebulae

Author

Long, K. S., Bamba, A., Aharonian, F., Foster, A., Funk, S., Hiraga, J., Hughes, J., Ishida, M., Katsuda, S., Matsumoto, H., Mori, K., Nakajima, H., Nakamori, T., Ozaki, M., Safi-Harb, S., Sawada, M., Tamagawa, T., Tamura, K., Tanaka, T., Tsunemi, H., Uchida, H., Uchiyama, Y., and Yamauchi, S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Most supernova remnants (SNRs) are old, in the sense that their structure has been profoundly modified by their interaction with the surrounding interstellar medium (ISM). Old SNRs are very heterogenous in terms of their appearance, reflecting differences in their evolutionary state, the environments in which SNe explode and in the explosion products. Some old SNRs are seen primarily as a result of a strong shock wave interacting with the ISM. Others, the so-called mixed-morphology SNRs, show central concentrations of emission, which may still show evidence of emission from the ejecta. Yet others, the pulsar wind nebulae (PWNe), are seen primarily as a result of emission powered by a pulsar; these SNRs often lack the detectable thermal emission from the primary shock. The underlying goal in all studies of old SNRs is to understand these differences, in terms of the SNe that created them, the nature of the ISM into which they are expanding, and the fundamental physical processes that govern their evolution. Here we identify three areas of study where ASTRO-H can make important contributions. These are constraining abundances and physical processes in mature limb-brightened SNRs, understanding the puzzling nature of mixed-morphology SNRs, and exploring the nature of PWNe. The Soft X-ray Spectrometer (SXS) on-board ASTRO-H will, as a result of its high spectral resolution, be the primary tool for addressing problems associated with old SNRs, supported by hard X-ray observations with the Hard X-ray Imager (HXI) to obtain broad band X-ray coverage., Comment: 25 pages, 17 figures, ASTRO-H White Paper

Published
2014

4. ASTRO-H White Paper - Young Supernova Remnants

Author

Hughes, J. P., Safi-Harb, S., Bamba, A., Katsuda, S., Leutenegger, M., Long, K. S., Maeda, Y., Mori, K., Nakajima, H., Sawada, M., Tanaka, T., Uchida, H., Yamaguchi, H., Aharonian, F., Funk, S., Hiraga, J., Ishida, M., Koyama, K., Matsumoto, H., Nobukawa, M., Ozaki, M., Tamagawa, T., Tsunemi, H., Tomida, H., Uchiyama, Y., and Uno, S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Thanks to the unprecedented spectral resolution and sensitivity of the Soft X-ray Spectrometer (SXS) to soft thermal X-ray emission, ASTRO-H will open a new discovery window for understanding young, ejecta-dominated, supernova remnants (SNRs). In particular we study how ASTRO-H observations will address, comprehensively, three key topics in SNR research: (1) using abundance measurements to unveil SNR progenitors, (2) using spatial and velocity distribution of the ejecta to understand supernova explosion mechanisms, (3) revealing the link between the thermal plasma state of SNRs and the efficiency of their particle acceleration., Comment: 38 pages, 19 figures, ASTRO-H White Paper

Published
2014

6. Multi-wavelength observations of blazar AO 0235+164 in the 2008-2009 flaring state

Author

Ackermann, M., Ajello, M., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bottacini, E., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Dubois, R., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Fuhrmann, L., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Hadasch, D., Hayashida, M., Hughes, R. E., Itoh, R., Johannesson, G., Johnson, A. S., Katagiri, H., Kataoka, J., Knodlseder, J., Kuss, M., Lande, J., Larsson, S., Lee, S. -H., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Nishino, S., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ozaki, M., Paneque, D., Panetta, J. H., Pelassa, V., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Rastawicki, D., Razzano, M., Readhead, A., Reimer, A., Reimer, O., Reyes, L. C., Richards, J. L., Sbarra, C., Sgro, C., Siskind, E. J., Spandre, G., Spinelli, P., Szostek, A., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Winer, B. L., Wood, K. S., Yang, Z., Zimmer, S., Moderski, R., Nalewajko, K., Sikora, M., Villata, M., Raiteri, C. M., Aller, H. D., Aller, M. F., Arkharov, A. A., Benitez, E., Berdyugin, A., Blinov, D. A., Boettcher, M., Calle, O. J. A. Bravo, Buemi, C. S., Carosati, D., Chen, W. P., Diltz, C., Di Paola, A., Dolci, M., Efimova, N. V., Forn\', E., Gurwell, M. A., Heidt, J., Hiriart, D., Jordan, B., Kimeridze, G., Konstantinova, T. S., Kopatskaya, E. N., Koptelova, E., Kurtanidze, O. M., Lahteenmaki, A., Larionova, E. G., Larionova, L. V., Larionov, V. M., Leto, P., Lindfors, E., Lin, H. C., Morozova, D. A., Nikolashvili, M. G., Nilsson, K., Oksman, M., Roustazadeh, P., Sievers, A., Sigua, L. A., Sillanpaa, A., Takahashi, T., Takalo, L. O., Tornikoski, M., Trigilio, C., Troitsky, I. S., Umana, G., Angelakis, E., Krichbaum, T. P., Nestoras, I., Riquelme, D., Krips, M., Trippe, S., Arai, A., Kawabata, K. S., Sakimoto, K., Sasada, M., Sato, S., Uemura, M., Yamanaka, M., Yoshida, M., Belloni, T., Tagliaferri, G., Bonning, E. W., Isler, J., Urry, C. M., Hoversten, E., Falcone, A., Pagani, C., and Stroh, M.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The blazar AO 0235+164 (z = 0.94) has been one of the most active objects observed by Fermi Large Area Telescope (LAT) since its launch in Summer 2008. In addition to the continuous coverage by Fermi, contemporaneous observations were carried out from the radio to {\gamma} -ray bands between 2008 September and 2009 February. In this paper, we summarize the rich multi-wavelength data collected during the campaign (including F-GAMMA, GASP- WEBT, Kanata, OVRO, RXTE, SMARTS, Swift, and other instruments), examine the cross-correlation between the light curves measured in the different energy bands, and interpret the resulting spectral energy distributions in the context of well-known blazar emission models. We find that the {\gamma} -ray activity is well correlated with a series of near-IR/optical flares, accompanied by an increase in the optical polarization degree. On the other hand, the X-ray light curve shows a distinct 20 day high state of unusually soft spectrum, which does not match the extrapolation of the optical/UV synchrotron spectrum. We tentatively interpret this feature as the bulk Compton emission by cold electrons contained in the jet, which requires an accretion disk corona with an effective covering factor of 19% at a distance of 100 Rg . We model the broadband spectra with a leptonic model with external radiation dominated by the infrared emission from the dusty torus., Comment: 48 pages, 8 figures

Published
2012
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7. Gamma-ray observations of the Orion Molecular Clouds with the Fermi Large Area Telescope

Author

Ackermann, M., Ajello, M., Allafort, A., Antolini, E., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cecchi, C., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., D'Ammando, F., de Angelis, A., de Palma, F., Dermer, C. D., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Enoto, T., Falletti, L., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fukazawa, Y., Fukui, Y., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hayashi, K., Horan, D., Hou, X., Hughes, R. E., Jackson, M. S., Jóhannesson, G., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Kerr, M., Knödlseder, J., Kuss, M., Lande, J., Larsson, S., Lee, S. -H., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Makishima, K., Mazziotta, M. N., Mehault, J., Mitthumsiri, W., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Naumann-Godo, M., Nishino, S., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Orienti, M., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Razzano, M., Reimer, A., Reimer, O., Roth, M., Sadrozinski, H. F. -W., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Strong, A. W., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. G., Thayer, J. B., Tibolla, O., Tinivella, M., Torres, D. F., Tramacere, A., Troja, E., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Yang, Z., and Zimmer, S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Galaxy Astrophysics
Abstract

We report on the gamma-ray observations of giant molecular clouds Orion A and B with the Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope. The gamma-ray emission in the energy band between \sim100 MeV and \sim100 GeV is predicted to trace the gas mass distribution in the clouds through nuclear interactions between the Galactic cosmic rays (CRs) and interstellar gas. The gamma-ray production cross-section for the nuclear interaction is known to \sim10% precision which makes the LAT a powerful tool to measure the gas mass column density distribution of molecular clouds for a known CR intensity. We present here such distributions for Orion A and B, and correlate them with those of the velocity integrated CO intensity (WCO) at a 1{\deg} \times1{\deg} pixel level. The correlation is found to be linear over a WCO range of ~10 fold when divided in 3 regions, suggesting penetration of nuclear CRs to most of the cloud volumes. The Wco-to-mass conversion factor, Xco, is found to be \sim2.3\times10^20 cm-2(K km s-1)-1 for the high-longitude part of Orion A (l > 212{\deg}), \sim1.7 times higher than \sim1.3 \times 10^20 found for the rest of Orion A and B. We interpret the apparent high Xco in the high-longitude region of Orion A in the light of recent works proposing a non-linear relation between H2 and CO densities in the diffuse molecular gas. Wco decreases faster than the H2 column density in the region making the gas "darker" to Wco., Comment: 41 pages, 10 figures (Accepted to ApJ)

Published
2012
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8. GeV Observations of Star-forming Galaxies with \textit{Fermi} LAT

Author

Fermi LAT Collaboration, Ackermann, M., Ajello, M., Allafort, A., Baldini, L., Ballet, J., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Cillis, A. N., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., De Palma, F., Dermer, C. D., Digel, S. W., Silva, E. Do Couto e, Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Fortin, P., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hays, E., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Martin, P., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nishino, S., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ozaki, M., Parent, D., Persic, M., Pesce-Rollins, M., Petrosian, V., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Ritz, S., Roth, M., Sbarra, C., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Stawarz, \{L}ukasz, Strong, A. W., Takahashi, H., Tanaka, T., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Vandenbroucke, J., Vianello, G., Vitale, V., Waite, A. P., Wood, M., and Yang, Z.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Recent detections of the starburst galaxies M82 and NGC 253 by gamma-ray telescopes suggest that galaxies rapidly forming massive stars are more luminous at gamma-ray energies compared to their quiescent relatives. Building upon those results, we examine a sample of 69 dwarf, spiral, and luminous and ultraluminous infrared galaxies at photon energies 0.1-100 GeV using 3 years of data collected by the Large Area Telescope (LAT) on the \textit{Fermi Gamma-ray Space Telescope} (\textit{Fermi}). Measured fluxes from significantly detected sources and flux upper limits for the remaining galaxies are used to explore the physics of cosmic rays in galaxies. We find further evidence for quasi-linear scaling relations between gamma-ray luminosity and both radio continuum luminosity and total infrared luminosity which apply both to quiescent galaxies of the Local Group and low-redshift starburst galaxies (conservative $P$-values $\lesssim0.05$ accounting for statistical and systematic uncertainties). The normalizations of these scaling relations correspond to luminosity ratios of $\log(L_{0.1-100 \rm{GeV}}/L_{1.4 \rm{GHz}}) = 1.7 \pm 0.1_{\rm (statistical)} \pm 0.2_{\rm (dispersion)}$ and $\log(L_{0.1-100 \rm{GeV}}/L_{8-1000 \mu\rm{m}}) = -4.3 \pm 0.1_{\rm (statistical)} \pm 0.2_{\rm (dispersion)}$ for a galaxy with a star formation rate of 1 $M_{\odot}$ yr$^{-1}$, assuming a Chabrier initial mass function. Using the relationship between infrared luminosity and gamma-ray luminosity, the collective intensity of unresolved star-forming galaxies at redshifts $0

Published
2012
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9. Search for Dark Matter Satellites using the FERMI-LAT

Author

The Fermi LAT Collaboration, Ackermann, M., Albert, A., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Essig, R., Falletti, L., Favuzzi, C., Fegan, S. J., Focke, W. B., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hou, X., Hughes, R. E., Johnson, R. P., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Knodlseder, J., Kuss, M., Lande, J., Latronico, L., Lee, S. -H., Lionetto, A. M., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Pelassa, V., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Ritz, S., Sadrozinski, H. F. -W., Sehgal, N., Sgro, C., Siskind, E. J., Spinelli, P., Strigari, L., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Troja, E., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Yang, Z., Zalewski, S., and Zimmer, S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

Numerical simulations based on the Lambda-CDM model of cosmology predict a large number of as yet unobserved Galactic dark matter satellites. We report the results of a Large Area Telescope (LAT) search for these satellites via the gamma-ray emission expected from the annihilation of weakly interacting massive particle (WIMP) dark matter. Some dark matter satellites are expected to have hard gamma-ray spectra, finite angular extents, and a lack of counterparts at other wavelengths. We sought to identify LAT sources with these characteristics, focusing on gamma-ray spectra consistent with WIMP annihilation through the $b \bar b$ channel. We found no viable dark matter satellite candidates using one year of data, and we present a framework for interpreting this result in the context of numerical simulations to constrain the velocity-averaged annihilation cross section for a conventional 100 GeV WIMP annihilating through the $b \bar b$ channel., Comment: 29 pages, 5 figures, 3 tables; Accepted by ApJ; Contact authors: Alex Drlica-Wagner, Ping Wang, Louie Strigari, and Elliott Bloom

Published
2012
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10. Simultaneous multi-wavelength campaign on PKS 2005-489 in a high state

Author

Collaboration, The H. E. S. S., Collaboration, the Fermi LAT, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gabici, S., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lenain, J. -P., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Nguyen, N., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Sushch, I., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zajczyk, A., Zdziarski, A. A., Zech, A., Zechlin, H. -S., Abdo, A. A., Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Cannon, A., Caraveo, P. A., Carrigan, S., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Çelik, Ö., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cutini, S., Dermer, C. D., de Palma, F., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Escande, L., Favuzzi, C., Ferrara, E. C., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Hadasch, D., Hays, E., Horan, D., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lee, S. -H., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Mazziotta, M. N., McConville, W., McEnery, J. E., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nishino, S., Nolan, P. L., Norris, J. P., Nuss, E., 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., Piron, F., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Sadrozinski, H. F. -W., Sanchez, D., Sander, A., Sgrò, C., Siskind, E. J., Smith, P. D., Spandre, G., Spinelli, P., Strickman, M. S., Suson, D. J., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Troja, E., Uehara, T., Usher, T. L., Vandenbroucke, J., Vianello, G., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Yang, Z., Ylinen, T., and Ziegler, M.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The high-frequency peaked BL Lac object PKS 2005-489 was the target of a multi-wavelength campaign with simultaneous observations in the TeV gamma-ray (H.E.S.S.), GeV gamma-ray (Fermi/LAT), X-ray (RXTE, Swift), UV (Swift) and optical (ATOM, Swift) bands. This campaign was carried out during a high flux state in the synchrotron regime. The flux in the optical and X-ray bands reached the level of the historical maxima. The hard GeV spectrum observed with Fermi/LAT connects well to the very high energy (VHE, E>100GeV) spectrum measured with H.E.S.S. with a peak energy between ~5 and 500 GeV. Compared to observations with contemporaneous coverage in the VHE and X-ray bands in 2004, the X-ray flux was ~50 times higher during the 2009 campaign while the TeV gamma-ray flux shows marginal variation over the years. The spectral energy distribution during this multi-wavelength campaign was fit by a one zone synchrotron self-Compton model with a well determined cutoff in X-rays. The parameters of a one zone SSC model are inconsistent with variability time scales. The variability behaviour over years with the large changes in synchrotron emission and small changes in the inverse Compton emission does not warrant an interpretation within a one-zone SSC model despite an apparently satisfying fit to the broadband data in 2009., Comment: published in A&A, 9pages, 4figures. Due to some style difficulties using the standard style file with the long author list, the abstract has been included manually. A version with the correct style can be found in the website http://www.lsw.uni-heidelberg.de/users/skaufman/publications/aa16170-10published.pdf

Published
2011
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11. Measurement of separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope

Author

The Fermi LAT Collaboration, Ackermann, M., Ajello, M., Allafort, A., Atwood, W. B., Baldini, L., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., de Angelis, A., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Gustafsson, M., Hadasch, D., Harding, A. K., Hayashida, M., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Madejski, G. M., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nolan, P. L., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Ormes, E. Orlando J. F., Ozaki, M., Paneque, D., Parent, D., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Romani, R. W., Roth, M., Sadrozinski, H. F. -W., Sbarra, C., Schalk, T. L., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Strong, A. W., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Winer, B. L., Wood, K. S., Wood, M., Yang, Z., and Zimmer, S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting the Earth's shadow, which is offset in opposite directions for opposite charges due to the Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 GeV and 200 GeV. We confirm that the fraction rises with energy in the 20-100 GeV range. The three new spectral points between 100 and 200 GeV are consistent with a fraction that is continuing to rise with energy., Comment: 5 figures, 1 table, revtex 4.1, updated to match PRL published version

Published
2011
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12. Constraining Dark Matter Models from a Combined Analysis of Milky Way Satellites with the Fermi Large Area Telescope

Author

Collaboration, The Fermi-LAT, Ackermann, M., Ajello, M., Albert, A., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Canadas, B., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., de Angelis, A., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Falletti, L., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hays, E., Hughes, R. E., Jeltema, T. E., Johannesson, G., Johnson, R. P., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lionetto, A. M., Garde, M. Llena, Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Parent, D., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Profumo, S., Raino, S., Razzano, M., Reimer, A., Reimer, O., Ritz, S., Roth, M., Sadrozinski, H. F. -W., Sbarra, C., Scargle, J. D., Schalk, T. L., Sgro, C., Siskind, E. J., Spandre, G., Spinelli, P., Strigari, L., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tinivella, M., Torres, D. F., Troja, E., Uchiyama, Y., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Wood, M., Yang, Z., Zimmer, S., Kaplinghat, M., and Martinez, G. D.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract

Satellite galaxies of the Milky Way are among the most promising targets for dark matter searches in gamma rays. We present a search for dark matter consisting of weakly interacting massive particles, applying a joint likelihood analysis to 10 satellite galaxies with 24 months of data of the Fermi Large Area Telescope. No dark matter signal is detected. Including the uncertainty in the dark matter distribution, robust upper limits are placed on dark matter annihilation cross sections. The 95% confidence level upper limits range from about 1e-26 cm^3 s^-1 at 5 GeV to about 5e-23 cm^3 s^-1 at 1 TeV, depending on the dark matter annihilation final state. For the first time, using gamma rays, we are able to rule out models with the most generic cross section (~3e-26 cm^3 s^-1 for a purely s-wave cross section), without assuming additional boost factors., Comment: 6 pages, 2 figures; Contact authors: Johann Cohen-Tanugi, Jan Conrad, and Maja Llena Garde

Published
2011
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13. The radio/gamma-ray connection in Active Galactic Nuclei in the era of the Fermi Large Area Telescope

Author

Ackermann, M., Ajello, M., Allafort, A., Angelakis, E., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Cannon, A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Charles, E., Chekhtman, A., Cheung, C. C., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cutini, S., de Palma, F., Dermer, C. D., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Escande, L., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Frailis, M., Fuhrmann, L., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grandi, P., Grenier, I. A., Guiriec, S., Hadasch, D., Hayashida, M., Hays, E., Healey, S. E., J, G., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Kn, J., Kuss, M., Lande, J., Lee, S. -H., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Max-Moerbeck, W., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Nishino, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Pavlidou, V., Pelassa, V., Pepe, M., Pesce-Rollins, M., Pierbattista, M., Piron, F., Porter, T. A., Rain, S., Razzano, M., Readhead, A., Reimer, A., Reimer, O., Richards, J. L., Romani, R. W., Sadrozinski, H. F. -W., Scargle, J. D., Sgr, C., Siskind, E. J., Smith, P. D., Spandre, G., Spinelli, P., Strickman, M. S., Suson, D. J., Takahashi, H., Tanaka, T., Taylor, G. B., Thayer, J. G., Thayer, J. B., Thompson, D. J., Torres, D. F., Tosti, G., Tramacere, A., Troja, E., Vandenbroucke, J., Vianello, G., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Yang, Z., and Ziegler, M.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present a detailed statistical analysis of the correlation between radio and gamma-ray emission of the Active Galactic Nuclei (AGN) detected by Fermi during its first year of operation, with the largest datasets ever used for this purpose. We use both archival interferometric 8.4 GHz data (from the VLA and ATCA, for the full sample of 599 sources) and concurrent single-dish 15 GHz measurements from the Owens Valley Radio Observatory (OVRO, for a sub sample of 199 objects). Our unprecedentedly large sample permits us to assess with high accuracy the statistical significance of the correlation, using a surrogate-data method designed to simultaneously account for common-distance bias and the effect of a limited dynamical range in the observed quantities. We find that the statistical significance of a positive correlation between the cm radio and the broad band (E>100 MeV) gamma-ray energy flux is very high for the whole AGN sample, with a probability <1e-7 for the correlation appearing by chance. Using the OVRO data, we find that concurrent data improve the significance of the correlation from 1.6e-6 to 9.0e-8. Our large sample size allows us to study the dependence of correlation strength and significance on specific source types and gamma-ray energy band. We find that the correlation is very significant (chance probability <1e-7) for both FSRQs and BL Lacs separately; a dependence of the correlation strength on the considered gamma-ray energy band is also present, but additional data will be necessary to constrain its significance., Comment: Accepted for publications by ApJ. Contact authors: M. Giroletti, V. Pavlidou, A. Reimer

Published
2011
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14. Gamma-Ray and Parsec-Scale Jet Properties of a Complete Sample of Blazars From the MOJAVE Program

Author

Lister, M. L., Aller, M., Aller, H., Hovatta, T., Kellermann, K. I., Kovalev, Y. Y., Meyer, E. T., Pushkarev, A. B., Ros, E., Ackermann, M., Antolini, E., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Boeck, M., Bonamente, E., Borgland, A. W., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Chang, C. S., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., de Palma, F., Dermer, C. D., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Finke, J., Focke, W. B., Fortin, P., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Hadasch, D., Hayashida, M., Hays, E., Horan, D., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Kadler, M., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Mazziotta, M. N., McConville, W., McEnery, J. E., Mehault, J., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Nishino, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ozaki, M., Paneque, D., Parent, D., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Rainò, S., Readhead, A., Reimer, A., Reimer, O., Richards, J. L., Ritz, S., Sadrozinski, H. F. -W., Sgrò, C., Shaw, M. S., Siskind, E. J., Spandre, G., Spinelli, P., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tosti, G., Tramacere, A., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., and Zimmer, S.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

We investigate the Fermi LAT gamma-ray and 15 GHz VLBA radio properties of a joint gamma-ray- and radio-selected sample of AGNs obtained during the first 11 months of the Fermi mission (2008 Aug 4 - 2009 Jul 5). Our sample contains the brightest 173 AGNs in these bands above declination -30 deg. during this period, and thus probes the full range of gamma-ray loudness (gamma-ray to radio band luminosity ratio) in the bright blazar population. The latter quantity spans at least four orders of magnitude, reflecting a wide range of spectral energy distribution (SED) parameters in the bright blazar population. The BL Lac objects, however, display a linear correlation of increasing gamma-ray loudness with synchrotron SED peak frequency, suggesting a universal SED shape for objects of this class. The synchrotron self-Compton model is favored for the gamma-ray emission in these BL Lacs over external seed photon models, since the latter predict a dependence of Compton dominance on Doppler factor that would destroy any observed synchrotron SED peak - gamma-ray loudness correlation. The high-synchrotron peaked (HSP) BL Lac objects are distinguished by lower than average radio core brightness temperatures, and none display large radio modulation indices or high linear core polarization levels. No equivalent trends are seen for the flat-spectrum radio quasars (FSRQ) in our sample. Given the association of such properties with relativistic beaming, we suggest that the HSP BL Lacs have generally lower Doppler factors than the lower-synchrotron peaked BL Lacs or FSRQs in our sample., Comment: 22 pages, 11 figures, 4 tables; accepted for publication in the Astrophysical Journal

Published
2011
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15. Fermi LAT Search for Photon Lines from 30 to 200 GeV and Dark Matter Implications

Author

The Fermi LAT Collaboration, Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Carrigan, S., Casandjian, J. M., Cecchi, C., Elik, O. C., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Dubois, R., Dumora, D., Edmonds, Y., Essig, R., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Gustafsson, M., Hadasch, D., Harding, A. K., Horan, D., Hughes, R. E., Jackson, M. S., ohannesson, G. J ., Johnson, A. S., Johnson, R. P., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., dlseder, J. Kno ., Kuss, M., Lande, J., Latronico, L., Garde, M. Llena, Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Mazziotta, M. N., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Rainó, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ripken, J., Ritz, S., Rodriguez, A. Y., Roth, M., Sadrozinski, H. F. -W., Sander, A., Parkinson, P. M. Saz, Scargle, J. D., Schalk, T. L., Sellerholm, A., Sgró, 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., Tanaka, T., Thayer, J. B., Thayer, J. G., Tibaldo, L., Torres, D. F., Uchiyama, Y., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Ylinen, T., and Ziegler, M.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Extragalactic Astrophysics, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

Dark matter (DM) particle annihilation or decay can produce monochromatic $\gamma$-rays readily distinguishable from astrophysical sources. $\gamma$-ray line limits from 30 GeV to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a $\gamma$-ray line analysis, and integrated over most of the sky. We obtain $\gamma$-ray line flux upper limits in the range $0.6-4.5\times 10^{-9}\mathrm{cm}^{-2}\mathrm{s}^{-1}$, and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed., Comment: 6 pages, 1 figure. Accepted for publication by The Physical Review Letters

Published
2010
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16. The NeXT Mission

Author

Takahashi, T., Kelley, R., Mitsuda, K., Kunieda, H., Petre, R., White, N., Dotani, T., Fujimoto, R., Fukazawa, Y., Hayashida, K., Ishida, M., Ishisaki, Y., Kokubun, M., Makishima, K., Koyama, K., Madejski, G. M., Mori, K., Mushotzky, R., Nakazawa, K., Ogasaka, Y., Ohashi, T., Ozaki, M., Tajima, H., Tashiro, M., Terada, Y., Tsunemi, H., Tsuru, T. G., Ueda, Y., Yamasaki, N., Watanabe, S., and team, the NeXT

Subjects
Astrophysics
Abstract

The NeXT (New exploration X-ray Telescope), the new Japanese X-ray Astronomy Satellite following Suzaku, is an international X-ray mission which is currently planed for launch in 2013. NeXT is a combination of wide band X-ray spectroscopy (3 - 80 keV) provided by multi-layer coating, focusing hard X-ray mirrors and hard X-ray imaging detectors, and high energy-resolution soft X-ray spectroscopy (0.3 - 10 keV) provided by thin-foil X-ray optics and a micro-calorimeter array. The mission will also carry an X-ray CCD camera as a focal plane detector for a soft X-ray telescope and a non-focusing soft gamma-ray detector. With these instruments, NeXT covers very wide energy range from 0.3 keV to 600 keV. The micro-calorimeter system will be developed by international collaboration lead by ISAS/JAXA and NASA. The simultaneous broad bandpass, coupled with high spectral resolution of Delta E ~ 7 eV by the micro-calorimeter will enable a wide variety of important science themes to be pursued., Comment: 14 pages, 10 figures, Proceedings of the SPIE meeting, "Space Telescopes and Instrumentation II: Ultraviolet to Gamma Ray 2008", Marseille (2008)

Published
2008
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17. Performance of the Charge Injection Capability of Suzaku XIS

Author

Nakajima, H., Yamaguchi, H., Matsumoto, H., Tsuru, T. G., Koyama, K., Tsunemi, H., Hayashida, K., Torii, K., Namiki, M., Katsuda, S., Shoji, M., Matsuura, D., Miyauchi, T., Dotani, T., Ozaki, M., Murakami, H., Bautz, M. W., Kissel, S. E., LaMarr, B., and Prigozhin, G. Y.

Subjects
Astrophysics
Abstract

A charge injection technique is applied to the X-ray CCD camera, XIS (X-ray Imaging Spectrometer) onboard Suzaku. The charge transfer inefficiency (CTI) in each CCD column (vertical transfer channel) is measured by the injection of charge packets into a transfer channel and subsequent readout. This paper reports the performances of the charge injection capability based on the ground experiments using a radiation damaged device, and in-orbit measurements of the XIS. The ground experiments show that charges are stably injected with the dispersion of 91eV in FWHM in a specific column for the charges equivalent to the X-ray energy of 5.1keV. This dispersion width is significantly smaller than that of the X-ray events of 113eV (FWHM) at approximately the same energy. The amount of charge loss during transfer in a specific column, which is measured with the charge injection capability, is consistent with that measured with the calibration source. These results indicate that the charge injection technique can accurately measure column-dependent charge losses rather than the calibration sources. The column-to-column CTI correction to the calibration source spectra significantly reduces the line widths compared to those with a column-averaged CTI correction (from 193eV to 173eV in FWHM on an average at the time of one year after the launch). In addition, this method significantly reduces the low energy tail in the line profile of the calibration source spectrum., Comment: Paper contains 18 figures and 15 tables. Accepted for publication in PASJ

Published
2007
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18. Measurements of total and partial charge-changing cross sections for 200-400 MeV/nucleon 12C in water and polycarbonate

Author

Toshito, T., Kodama, K., Sihver, L., Yusa, K., Ozaki, M., Amako, K., Kameoka, S., Murakami, K., Sasaki, T., Aoki, S., Ban, T., Fukuda, T., Komatsu, M., Kubota, H., Naganawa, N., Nakamura, T., Nakano, T., Natsume, M., Niwa, K., Takahashi, S., Yoshida, J., Yoshida, H., Kanazawa, M., Kanematsu, N., Komori, M., Sato, S., Asai, M., Koi, T., Fukushima, C., Ogawa, S., Shibasaki, M., and Shibuya, H.

Subjects
Nuclear Experiment
Abstract

We have studied charged nuclear fragments produced by 200 - 400 MeV/nucleon carbon ions, interacting with water and polycarbonate, using a newly developed emulsion detector. Total and partial charge-changing cross sections for the production of B, Be, and Li fragments were measured and compared with both previously published measurements, and model predictions. This study is of importance for validating and improving carbon ion therapy treatment planning systems, and for estimating the radiological risks for personnel on space missions, since carbon is a significant component of the Galactic Cosmic Rays., Comment: 28 pages, 13 figures

Published
2007
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19. Monte-Carlo Simulator and Ancillary Response Generator of Suzaku XRT/XIS System for Spatially Extended Source Analysis

Author

Ishisaki, Y., Maeda, Y., Fujimoto, R., Ozaki, M., Ebisawa, K., Takahashi, T., Ueda, Y., Ogasaka, Y., Ptak, A., Mukai, K., Hamaguchi, K., Hirayama, M., Kotani, T., Kubo, H., Shibata, R., Ebara, M., Furuzawa, A., Iizuka, R., Inoue, H., Mori, H., Okada, S., Yokoyama, Y., Matsumoto, H., Nakajima, H., Yamaguchi, H., Anabuki, N., Tawa, N., Nagai, M., Katsuda, S., Hayashida, K., Bamba, A., Miller, E. D., Sato, K., and Yamasaki, N. Y.

Subjects
Astrophysics
Abstract

We have developed a framework for the Monte-Carlo simulation of the X-Ray Telescopes (XRT) and the X-ray Imaging Spectrometers (XIS) onboard Suzaku, mainly for the scientific analysis of spatially and spectroscopically complex celestial sources. A photon-by-photon instrumental simulator is built on the ANL platform, which has been successfully used in ASCA data analysis. The simulator has a modular structure, in which the XRT simulation is based on a ray-tracing library, while the XIS simulation utilizes a spectral "Redistribution Matrix File" (RMF), generated separately by other tools. Instrumental characteristics and calibration results, e.g., XRT geometry, reflectivity, mutual alignments, thermal shield transmission, build-up of the contamination on the XIS optical blocking filters (OBF), are incorporated as completely as possible. Most of this information is available in the form of the FITS (Flexible Image Transport System) files in the standard calibration database (CALDB). This simulator can also be utilized to generate an "Ancillary Response File" (ARF), which describes the XRT response and the amount of OBF contamination. The ARF is dependent on the spatial distribution of the celestial target and the photon accumulation region on the detector, as well as observing conditions such as the observation date and satellite attitude. We describe principles of the simulator and the ARF generator, and demonstrate their performance in comparison with in-flight data., Comment: 19 pages with 8 figures, accepted for publication in PASJ Vol 58, Suzaku special issue

Published
2006
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20. Wide band X-ray Imager (WXI) and Soft Gamma-ray Detector (SGD) for the NeXT Mission

Author

Takahashi, T., Awaki, A., Dotani, T., Fukazawa, Y., Hayashida, K., Kamae, T., Kataoka, J., Kawai, N., Kitamoto, S., Kohmura, T., Kokubun, M., Koyama, K., Makishima, K., Matsumoto, H., Miyata, E., Murakami, T., Nakazawa, K., Momachi, M., Ozaki, M., Tajima, H., Tashiro, M., Tamagawa, T., Terada, Y., Tsunemi, H., Tsuru, T., Yamaoka, K., Yonetoku, D., and Yoshida, A.

Subjects
Astrophysics
Abstract

The NeXT mission has been proposed to study high-energy non-thermal phenomena in the universe. The high-energy response of the super mirror will enable us to perform the first sensitive imaging observations up to 80 keV. The focal plane detector, which combines a fully depleted X-ray CCD and a pixellated CdTe detector, will provide spectra and images in the wide energy range from 0.5 keV to 80 keV. In the soft gamma-ray band up to ~1 MeV, a narrow field-of-view Compton gamma-ray telescope utilizing several tens of layers of thin Si or CdTe detector will provide precise spectra with much higher sensitivity than present instruments. The continuum sensitivity will reach several times 10^(-8) photons/s/keV/cm^(2) in the hard X-ray region and a few times10^(-7) photons/s/keV/cm^(2) in the soft gamma-ray region., Comment: 12 pages, 13 figures, to be published in the SPIE proceedings 5488, typo corrected in sec.3

Published
2004
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21. Cosmic-Ray Background Flux Model based on a Gamma-Ray Large-Area Space Telescope Balloon Flight Engineering Model

Author

Mizuno, T., Kamae, T., Godfrey, G., Handa, T., Thompson, D. J., Lauben, D., Fukazawa, Y., and Ozaki, M.

Subjects
Astrophysics
Abstract

Cosmic-ray background fluxes were modeled based on existing measurements and theories and are presented here. The model, originally developed for the Gamma-ray Large Area Space Telescope (GLAST) Balloon Experiment, covers the entire solid angle (${\rm 4\pi sr}$), the sensitive energy range of the instrument (${\rm \sim 10 MeV to 100 GeV}$) and abundant components (proton, alpha, $e^{-}$, $e^{+}$, $\mu^{-}$, $\mu^{+}$ and gamma). It is expressed in analytic functions in which modulations due to the solar activity and the Earth geomagnetism are parameterized. Although the model is intended to be used primarily for the GLAST Balloon Experiment, model functions in low-Earth orbit are also presented and can be used for other high energy astrophysical missions. The model has been validated via comparison with the data of the GLAST Balloon Experiment., Comment: 35 pages with 14 figures, accepted for publication (ApJ)

Published
2004
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22. Gamma Ray Large Area Space Telescope (GLAST) Balloon Flight Data Handling Overview

Author

Burnett, T. H., Chekhtman, A., Silva, E. do Couto e, Dubois, R., Flath, D., Gable, I., Grove, J. E., Hartman, R., Kamae, T., Kavelaars, A., Kelly, H., Kotani, T., Kuss, M., Lauben, D., Lindner, T., Lumb, N., Mizuno, T., Moiseev, A., Ozaki, M., Rochester, L. S., Schaefer, R., Spandre, G., Thompson, D. J., Usher, T., and Young, K.

Subjects
Astrophysics
Abstract

The GLAST Balloon Flight Engineering Model (BFEM) represents one of 16 towers that constitute the Large Area Telescope (LAT), a high-energy (>20 MeV) gamma-ray pair-production telescope being built by an international partnership of astrophysicists and particle physicists for a satellite launch in 2006. The prototype tower consists of a Pb/Si pair-conversion tracker (TKR), a CsI hodoscopic calorimeter (CAL), an anti-coincidence detector (ACD) and an autonomous data acquisition system (DAQ). The self-triggering capabilities and performance of the detector elements have been previously characterized using positron, photon and hadron beams. External target scintillators were placed above the instrument to act as sources of hadronic showers. This paper provides a comprehensive description of the BFEM data-reduction process, from receipt of the flight data from telemetry through event reconstruction and background rejection cuts. The goals of the ground analysis presented here are to verify the functioning of the instrument and to validate the reconstruction software and the background-rejection scheme., Comment: 5 pages, 4 figures, to be published in IEEE Transacations on Nuclear Science, August 2002

Published
2002
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23. Possible Triplet Electron Pairing and an Anisotropic Spin Susceptibility in Organic Superconductors (TMTSF)_2 X

Author

Lebed, A. G., Machida, K., and Ozaki, M.

Subjects
Condensed Matter
Abstract

We argue that (TMTSF)_2 PF_6 compound under pressure is likely a triplet superconductor with a vector order parameter d(k) \equiv (d_a(k) \neq 0, d_c(k) = ?, d_{b'}(k) = 0); |d_a(k)| > |d_c(k)|. It corresponds to an anisotropic spin susceptibility at T=0: \chi_{b'} = \chi_0, \chi_a \ll \chi_0, where \chi_0 is its value in a metallic phase. [The spin quantization axis, z, is parallel to a so-called b'-axis]. We show that the suggested order parameter explains why the upper critical field along the b'-axis exceeds all paramagnetic limiting fields, including that for a nonuniform superconducting state, whereas the upper critical field along the a-axis (a \perp b') is limited by the Pauli paramagnetic effects [I. J. Lee, M. J. Naughton, G. M. Danner and P. M. Chaikin, Phys. Rev. Lett. 78, 3555 (1997)]. The triplet order parameter is in agreement with the recent Knight shift measurements by I. J. Lee et al. as well as with the early results on a destruction of superconductivity by nonmagnetic impurities and on the absence of the Hebel-Slichter peak in the NMR relaxation rate., Comment: 4 pages, 1 eps figure

Published
2000
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25. A Possible Site of Cosmic Ray Acceleration in the Supernova Remnant IC 443

Author

Keohane, Jonathan W., Petre, R., Gotthelf, E. V., Ozaki, M., and Koyama, K.

Subjects
Astrophysics
Abstract

We present evidence for shock acceleration of cosmic rays to high energies (about 10 TeV) in the supernova remnant IC 443. X-ray imaging spectroscopy with ASCA reveals two regions of particularly hard emission: an unresolved source embedded in an extended emission region, and a ridge of emission coincident with the southeastern rim. Both features are located on part of the radio shell where the shock wave is interacting with molecular gas, and together they account for a majority of the emission at 7 keV. Though we would not have noticed it a priori, the unresolved feature is coincident with one resolved by the ROSAT HRI. Because this feature overlaps a unique region of flat radio spectral index (alpha < 0.24), has about equal light-crossing and synchrotron loss times, and a power law spectrum with a spectral index of 2, we conclude that the hard X-ray feature is synchrotron radiation from a site of enhanced particle acceleration. Evidence against a plerion includes a lack of observed periodicity (the pulsed fraction upper limit is 33%), the spectral similarity with the more extended hard region, the location of the source outside the 95% error circle of the nearby EGRET source, the fact that it is nestled in a bend in the molecular cloud ring with which IC 443 is interacting, and the requirement of an extremely high transverse velocity (>5,000 km/s). We conclude that the anomalous feature is most likely tracing enhanced particle acceleration by shocks that are formed as the supernova blast wave impacts the ring of molecular clouds., Comment: 10 pages with embedded figures; accepted by the Ap.J; author's web pages at http://lheawww.gsfc.nasa.gov/users/jonathan/ , http://lheawww.gsfc.nasa.gov/users/rob/Vita/petre.html , http://lheawww.gsfc.nasa.gov/users/evg/evg.html

Published
1997
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26. Efficacy of 0.05% epinastine and 0.1% olopatadine for allergic conjunctivitis as seasonal and preseasonal treatment

Author

Mizoguchi T, Ozaki M, and Ogino N

Subjects
0.05%Epinastine, 0.1%Olopatadine, seasonal allergic conjunctivitis, pre-seasonal treatment, seasonal treatment, inverse agonist., Ophthalmology, RE1-994
Abstract

Takanori Mizoguchi,1 Mineo Ozaki,2 Nobuchika Ogino3 1Mizoguchi Eye Clinic, Ophthalmology, Sasebo, Japan; 2Ozaki Eye Hospital, Ophthalmology, Miyazaki, Japan; 3Nishigaki Eye Clinic, Ophthalmology, Nagoya, Japan Purpose: To evaluate the efficacy and safety of 0.05% epinastine and 0.1% olopatadine eye drop preparations as seasonal and preseasonal treatments in patients with seasonal allergic conjunctivitis (SAC). Subjects and methods: This was a prospective, randomized, case-control study involving two institutions. The subjects were patients diagnosed with SAC at two institutions between February and March in 2014. To examine the clinical effects of seasonal treatment, 0.05% epinastine and 0.1% olopatadine were administered, and their effects were investigated every 2 weeks (Stage 1). To evaluate the clinical effects of preseasonal therapy, in January 2015, the same eye drop preparations as adopted in Stage 1 were administered to patients who had participated in Stage 1 and provided consent to participate in this study, and their effects were investigated every month (Stage 2). Results: In Stage 1, the 0.05% epinastine group consisted of 43 patients, and the 0.1% olopatadine group consisted of 42 patients. There were significant improvements in the total symptom and objective finding scores at each time point after administration in comparison with those before its baseline, but there were no significant differences between the two groups. In Stage 2, the 0.05% epinastine group consisted of 15 patients, and the 0.1% olopatadine group consisted of 14 patients. The rate of change in the total symptom score in comparison with that at the baseline of preseasonal treatment was significantly higher in the 0.1% olopatadine group 1 month after the start of treatment, suggesting symptom deterioration (P=0.025). There was no significant difference in the rate of change in the total objective finding score between the two groups. Conclusion: Seasonal treatment with 0.05% epinastine or 0.1% olopatadine was equally effective for patients with allergic conjunctivitis. However, for preseasonal therapy, 0.05% epinastine was more effective than 0.1% olopatadine. Keywords: 0.05% epinastine, 0.1% olopatadine, seasonal allergic conjunctivitis, preseasonal treatment, seasonal treatment, inverse agonist

Published
2017

27. A statistical study of longitudinal extent of Pc1 pulsations using seven PWING ground stations at subauroral latitudes

Author

Liu, J. (Jie), Shiokawa, K. (Kazuo), Oyama, S.-I. (Shin-Ichiro), Otsuka, Y. (Yuichi), Jun, C.-W. (Chae-Woo), Nosé, M. (Masahito), Nagatsuma, T. (Tsutomu), Sakaguchi, K. (Kaori), Kadokura, A. (Akira), Ozaki, M. (Mitsunori), Connors, M. (Martin), Baishev, D. (Dmitry), Nishitani, N. (Nozomu), Oinats, A. (Alexey), Kurkin, V. (Vladimir), Raita, T. (Tero), Liu, J. (Jie), Shiokawa, K. (Kazuo), Oyama, S.-I. (Shin-Ichiro), Otsuka, Y. (Yuichi), Jun, C.-W. (Chae-Woo), Nosé, M. (Masahito), Nagatsuma, T. (Tsutomu), Sakaguchi, K. (Kaori), Kadokura, A. (Akira), Ozaki, M. (Mitsunori), Connors, M. (Martin), Baishev, D. (Dmitry), Nishitani, N. (Nozomu), Oinats, A. (Alexey), Kurkin, V. (Vladimir), and Raita, T. (Tero)

Abstract

Pc1 geomagnetic pulsations correspond to electromagnetic ion cyclotron (EMIC) waves in the magnetosphere and are excited there with frequencies of 0.2–5 Hz. The instantaneous longitudinal extent of Pc1 waves on the ground has not been estimated yet. In this study, we analyze the Pc1 pulsations observed at seven longitudinally-distributed ground stations at subauroral latitudes at ∼60° magnetic latitude for 1 year from July 2018 to June 2019. The hourly occurrence rates of Pc1 pulsations at all 7 stations have a peak (14%–39.6%) in the post-noon sector and a local minimum (4.1%–8.1%) at midnight. The average frequencies become highest (0.6–1.1 Hz) after midnight and lowest (0.3–0.5 Hz) after noon at all 7 stations. An increasing tendency of total Pc1 occurrence with respect to magnetic latitude was observed. Based on these observations, we obtained a peak of probability distribution of the instantaneous Pc1 longitudinal extent as ∼82.5° with a half maximum at ∼114°, though this probability distribution can be affected by the limitation of the number of the stations. We also made model calculations on the possible longitudinal extent using artificial random Pc1 waves with fixed extents. The comparison of the model results with the observation suggests longitudinal extent of 70°–86° comparable to the peak of probability distribution (∼82.5°). A superposed epoch analysis shows that the longitudinal extent of Pc1 waves tends to increase during recovery phase of geomagnetic storms.

Published
2023

28. Characteristics and longitudinal extent of VLF quasi-periodic emissions using multi-point ground-based observations

Author

Martinez-Calderon, C. (Claudia), Oonishi, T. (Tomoka), Shiokawa, K. (Kazuo), Manninen, J. K. (Jyrki K.), Oinats, A. (Alexey), Ozaki, M. (Mitsunori), Martinez-Calderon, C. (Claudia), Oonishi, T. (Tomoka), Shiokawa, K. (Kazuo), Manninen, J. K. (Jyrki K.), Oinats, A. (Alexey), and Ozaki, M. (Mitsunori)

Abstract

Quasi-periodic (QP) emissions are a type of magnetospheric ELF/VLF waves characterized by a periodic intensity modulation ranging from tens of seconds to several minutes. Here, we present 63 QP events observed between January 2017 and December 2018. Initially detected at the VLF receiver in Kannuslehto, Finland (KAN, MLAT = 67.7°N, L = 5.5), we proceeded to check whether these events were simultaneously observed at other subauroral receivers. To do so we used the following PWING stations: Athabasca (ATH, MLAT = 61.2°N, L = 4.3, Canada), Gakona (GAK, MLAT = 63.6°N, L = 4.9, Alaska), Husafell (HUS, MLAT = 64.9°N, L = 5.6, Iceland), Istok (IST, MLAT = 60.6°N, L = 6.0, Russia), Kapuskasing (KAP, MLAT = 58.7°N, L = 3.8, Canada), Maimaga (MAM, MLAT = 58.0°N, L = 3.6, Russia), and Nain (NAI, MLAT = 65.8°N, L = 5.0, Canada). We found that: (1) QP emissions detected at KAN had a relatively longer observation time (1–10 h) than other stations, (2) 11.3% of the emissions at KAN were observed showing one-to-one correspondence at IST, and (3) no station other than IST simultaneously observed the same QP emission as KAN. Since KAN and IST are longitudinally separated by 60.6°, we estimate that the maximum meridional spread of conjugated QP emissions should be close to 60° or 4 MLT. Comparison with geomagnetic data shows half of the events are categorized as type II, while the rest are mixed (type I and II). This study is the first to clarify the longitudinal spread of QP waves observed on the ground by analyzing simultaneous observations over 2 years using multiple ground stations.

Published
2023

29. Plateau iris in Japanese patients with primary angle closure and primary angle closure glaucoma

Author

Mizoguchi T, Ozaki M, Wakiyama H, and Ogino N

Subjects
Ophthalmology, RE1-994
Abstract

Takanori Mizoguchi,1 Mineo Ozaki,2,3 Harumi Wakiyama,1,4 Nobuchika Ogino1,51Mizoguchi Eye Clinic, Nagasaki, Japan; 2Ozaki Eye Clinic Miyazaki, Japan; 3Department of Ophthalmology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan; 4The Japanese Red Cross Nagasaki Genbaku Hospital, Nagasaki, Japan; 5Nishigaki Eye Clinic, Nagoya, JapanPurpose: To determine the prevalence of plateau iris in Japanese patients with primary angle closure (PAC) and primary angle closure glaucoma (PACG) and analyze the biometric parameters in patients with plateau iris using ultrasound biomicroscopy (UBM).Methods: In this cross-sectional observational study, subjects aged >50 years with PAC and PACG who had previously undergone a patent laser peripheral iridotomy underwent UBM in one eye. UBM images were qualitatively analyzed using standardized criteria. Plateau iris in a quadrant was defined by anteriorly directed ciliary body, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact. At least two quadrants had to fulfill these UBM criteria for an eye to be classified as having plateau iris. A-scan biometry was used to measure anterior segment parameters.Results: Ninety-one subjects with PAC (58 subjects) or PACG (33 subjects) and 68 normal controls were recruited. The mean (standard deviation) ages of PAC and PACG patients and normal controls were 73.5 (6.2) and 72.6 (7.3), respectively. Based on UBM criteria, plateau iris was found in 16 eyes (17.6%) of 91 eyes. In these 16 eyes, quadrant-wise analysis showed ten eyes (62.5%) had plateau iris in two quadrants; four eyes (25%) had plateau iris in three quadrants; and two eyes (12.5%) had plateau iris in four quadrants. Anterior chamber depth, lens thickness, axial length, lens position, and relative lens position were not statistically significant between the group having plateau iris and that not having plateau iris, respectively.Conclusion: Approximately 20% of Japanese subjects with PAC and PACG with a patent laser peripheral iridotomy were found to have plateau iris on UBM. No morphological difference was noted in the anterior segment of the eye between those with or without plateau iris.Keywords: ultrasound biomicroscopy, biometric parameters of anterior segment, plateau iris, angle closure

Published
2015

30. Peripheral iris thickness and association with iridotrabecular contact after laser peripheral iridotomy in patients with primary angle-closure and primary angle-closure glaucoma

Author

Mizoguchi T, Ozaki M, Wakiyama H, and Ogino N

Subjects
Ophthalmology, RE1-994
Abstract

Takanori Mizoguchi,1 Mineo Ozaki,2,3 Harumi Wakiyama,1,4 Nobuchika Ogino1,5 1Mizoguchi Eye Clinic, Sasebo, Japan; 2Ozaki Eye Clinic, Miyazaki, Japan; 3Department of Ophthalmology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan; 4Japanese Red Cross Nagasaki Genbaku Hospital, Nagasaki, Japan; 5Nishigaki Eye Clinic, Nagoya, Japan Purpose: To investigate the relation between the quantitative iris parameters and iridotrabecular contact (ITC) in patients with primary angle-closure (PAC) and PAC glaucoma (PACG). Materials and methods: PAC and PACG with laser peripheral iridotomy were recruited prospectively. Anterior-segment optical coherence tomography (ASOCT) was performed under light and dark conditions, and scans were taken along the vertical and horizontal axes. Iris thickness at 500 µm (IT500) and 750 µm (IT750) from the scleral spur, maximal iris thickness (MIT), and cross sections of the iris area (I-Area) were measured by using software. ITC was defined by the ASOCT as the contact between the peripheral iris and angle wall anterior to the scleral spur. The ITC+ and ITC- groups were defined as eyes that had ITC in two or more quadrants and in no or one quadrant, respectively. Results: A total of 79 eyes of 60 patients (consisting of 48 PAC and 31 PACG) were recruited. The prevalence of superior, inferior, temporal, and nasal ITC was 44 eyes (55.7%), 48 eyes (60.8%), 18 eyes (22.8%), and 16 eyes (20.2%), respectively. These iris parameters of the inferior quadrant, which had the highest prevalence of all the quadrants, were used for the analysis. After adjusting for age, sex, pupil size, and central anterior chamber depth, mean values of IT500 and IT750 were significantly greater in the ITC+ group than the ITC- group (P

Published
2014

31. Quantifying the Size and Duration of a Microburst‐Producing Chorus Region on 5 December 2017

Author

Elliott, S. S., primary, Breneman, A. W., additional, Colpitts, C., additional, Pettit, J. M., additional, Cattell, C. A., additional, Halford, A. J., additional, Shumko, M., additional, Sample, J., additional, Johnson, A. T., additional, Miyoshi, Y., additional, Kasahara, Y., additional, Cully, C. M., additional, Nakamura, S., additional, Mitani, T., additional, Hori, T., additional, Shinohara, I., additional, Shiokawa, K., additional, Matsuda, S., additional, Connors, M., additional, Ozaki, M., additional, and Manninen, J., additional

Published
2022
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33. A Cocoon of Freshly Accelerated Cosmic Rays Detected by Fermi in the Cygnus Superbubble

Author

Ackermann, M., Ajello, M., Allafort, A., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Belfiore, A., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bottacini, E., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., de Angelis, A., de Palma, F., Dermer, C. D., do Couto e Silva, E., Drell, P. S., Dumora, D., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Fukazawa, Y., Fusco, P., Gargano, F., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guillemot, L., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hayashi, K., Hays, E., Jóhannesson, G., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Kerr, M., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lee, S.-H., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Martin, P., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Nolan, P. L, Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Parent, D., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pohl, M., Prokhorov, D., Rainò, S., Rando, R., Razzano, M., Reposeur, T., Ritz, S., Parkinson, P. M. Saz, Sgrò, C., Siskind, E. J., Smith, P. D., Spinelli, P., Strong, A. W., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Troja, E., Uchiyama, Y., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wang, P., Winer, B. L, Wood, K. S., Yang, Z., Zimmer, S., and Bontemps, S.

Published
2011
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34. Gamma-Ray Flares from the Crab Nebula

Author

Abdo, A. A., Ackermann, M., Ajello, M., Allafort, A., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Brandt, T. J., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Cannon, A., Caraveo, P. A., Casandjian, J. M., Celik, Ö., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Costamante, L., Cutini, S., D'Ammando, F., Dermer, C. D., de Angelis, A., de Luca, A., de Palma, F., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Dubois, R., Dumora, D., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashi, K., Hayashida, M., Hays, E., Horan, D., Itoh, R., Jóhannesson, G., Johnson, A. S., Johnson, T. J., Khangulyan, D., Kamae, T., Katagiri, H., Kataoka, J., Kerr, M., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lee, S.-H., Lemoine-Goumard, M., Longo, F., Loparco, F., Lubrano, P., Madejski, G. M., Makeev, A., Marelli, M., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Naumann-Godo, M., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Ormes, J. F., Ozaki, M., Paneque, D., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Pierbattista, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Ray, P. S., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Romani, R. W., Sadrozinski, H. F.-W., Sanchez, D., Parkinson, P. M. Saz, Scargle, J. D., Schalk, T. L., Sgrò, C., Siskind, E. J., Smith, P. D., Spandre, G., Spinelli, P., Strickman, M. S., Suson, D. J., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. B., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Troja, E., Uchiyama, Y., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Wang, P., Wood, K. S., Yang, Z., and Ziegler, M.

Published
2011
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35. A randomized crossover study comparing tafluprost 0.005% with travoprost 0.004% in patients with normal-tension glaucoma

Author

Mizoguchi T, Ozaki M, Unoki K, Dake Y, Eto T, and Arai M

Subjects
Ophthalmology, RE1-994
Abstract

Takanori Mizoguchi,1 Mineo Ozaki,2 Kazuhiko Unoki,3 Yoshinori Dake,4 Takahiko Eto,5 Miki Arai61Mizoguchi Eye Clinic, 2Ozaki Eye Clinic, Miyazaki, Japan; 3Unoki Eye Clinic, Kagoshima, Japan; 4Dake Eye Clinic, Nagasaki, Japan; 5Eto Eye Clinic, Oita, Japan; 6Arai Eye Clinic, Fukuoka, JapanPurpose: We compared the intraocular pressure (IOP)-lowering effect of tafluprost 0.0015% once daily with travoprost 0.004% once daily in Japanese patients with normal-tension glaucoma (NTG).Methods: One hundred sixteen patients with NTG were randomized to use tafluprost 0.0015% or travoprost 0.004% once daily for 12 weeks, followed by a washout period of 4 weeks between switching medications. IOP was measured at baseline and 4, 8, and 12 weeks of each treatment period.Results: Ninety patients completed both treatment periods and had IOP data available for evaluation. In both groups, a significant decrease in IOP was observed for all measurement points compared with baseline values (P < 0.0001). There was no significant difference in IOP at each time point between the two groups. Both drugs were effective (defined as more than 10% IOP reduction) in 39 (43%) of 90 patients; only tafluprost was effective in 26 (29%) patients, and only travoprost was effective in 17 (19%) patients. Eight (9%) patients were nonresponders to both drugs.Conclusions: Tafluprost and travoprost were equally effective in lowering IOP in patients with normal-tension glaucoma. However, patients with normal-tension glaucoma may vary in response to each medication.Keywords: intraocular pressure reduction, normal-tension glaucoma, responder, tafluprost 0.005%, travoprost 0.004%

Published
2012

36. Additive intraocular pressure-lowering effect of dorzolamide 1%/timolol 0.5% fixed combination on prostaglandin monotherapy in patients with normal tension glaucoma

Author

Mizoguchi T, Ozaki M, Wakiyama H, and Ogino N

Subjects
Ophthalmology, RE1-994
Abstract

Takanori Mizoguchi1, Mineo Ozaki2, Harumi Wakiyama1,3, Nobuchika Ogino11Mizoguchi Eye Clinic, Sasebo, 2Ozaki Eye Clinic and Dept of Opthalmology, Faculty of Medicine, University of Miyazaki, Miyazaki, 3The Japanese Red Cross Nagasaki Genbaku Hospital, Nagasaki, JapanPurpose: To evaluate the intraocular pressure (IOP)-lowering effect of adding dorzolamide 1.0%/timolol 0.5% fixed combination (DTFC) to prostaglandin analogs (PGAs) as monotherapy in patients with normal tension glaucoma.Methods: A prospective, clinical, case-controlled study of patients with normal tension glaucoma. Patients had been on a once-daily night dose of prostaglandins (PGs) as monotherapy and then received DTFC added to PGs for 8 weeks. The IOP was measured at 9 am, week 0 (baseline), week 4, and week 8.Results: The baseline IOP of 40 patients who had previously been treated by prostaglandin monotherapy was 15.6 ± 2.0 mmHg at baseline. The IOPs at 4 and 8 weeks after adding DTFC to PGs were 13.5 ± 2.1 mmHg and 13.7 ± 2.2 mmHg, respectively. Significant decrease of the IOP was observed at each time point of measurement as compared with the baseline IOP before adding DTFC (P = 0.01). The percent IOP reduction from the baseline IOP at week 4 and week 8 was 13.5% ± 12.3% and 11.7% ± 13.1%, respectively. The percentage of patients who achieved 10% or more IOP reduction from the baseline IOP at week 8 was 62.5%. The baseline IOP was significantly correlated with the percent IOP reduction at week 8 (P = 0.03, r = 0.34).Conclusion: DTFC therapy added to PGAs as glaucoma monotherapy is effective in patients with normal tension glaucoma.Keywords: IOP-lowering effect, prostaglandin, dorzolamide 1%/timolol 0.5% fixed combination, fixed combination, normal tension glaucoma

Published
2011

37. Impact of Vertical Atmospheric Structure on an Atypical Fire in a Mountain Valley

Author

Ozaki, M, Harris, RMB, Love, PT, Aryal, J, Fox-Hughes, P, Williamson, GJ, Ozaki, M, Harris, RMB, Love, PT, Aryal, J, Fox-Hughes, P, and Williamson, GJ

Abstract

Wildfires are not only a natural part of many ecosystems, but they can also have disastrous consequences for humans, including in Australia. Rugged terrain adds to the difficulty of predicting fire behavior and fire spread, as fires often propagate contrary to expectations. Even though fire models generally incorporate weather, fuels, and topography, which are important factors affecting fire behavior, they usually only consider the surface wind; however, the more elevated winds should also be accounted for, in addition to surface winds, when predicting fire spread in rugged terrain because valley winds are often dynamically altered by the interaction of a layered atmosphere and the topography. Here, fire spread in rugged terrain was examined in a case study of the Riveaux Road Fire, which was ignited by multiple lightning strikes in January 2019 in southern Tasmania, Australia and burnt approximately 637.19 km2. Firstly, the number of conducive wind structures, which are defined as the combination of wind and temperature layers likely to result in enhanced surface wind, were counted by examining the vertical wind structure of the atmosphere, and the potential for above-surface winds to affect fire propagation was identified. Then, the multiple fire propagations were simulated using a new fire simulator (Prototype 2) motivated by the draft specification of the forthcoming new fire danger rating system, the Australian Fire Danger Rating System (AFDRS). Simulations were performed with one experiment group utilizing wind fields that included upper-air interactions, and two control groups that utilized downscaled wind from a model that only incorporated surface winds, to identify the impact of upper air interactions. Consequently, a detailed analysis showed that more conducive structures were commonly observed in the rugged terrain than in the other topography. In addition, the simulation of the experiment group performed better in predicting fire spread than those of t

Published
2022

38. Slow contraction of flash aurora induced by an isolated chorus element ranging from lower-band to upper-band frequencies in the source region

Author

Ozaki, M. (Mitsunori), Yagitani, S. (Satoshi), Shiokawa, K. (Kazuo), Tanaka, Y. (Yoshimasa), Ogawa, Y. (Yasunobu), Hosokawa, K. (Keisuke), Kasahara, Y. (Yoshiya), Ebihara, Y. (Yusuke), Miyoshi, Y. (Yoshizumi), Imamura, K. (Kousuke), Kataoka, R. (Ryuho), Oyama, S.-I. (Shin-Ichiro), Chida, T. (Teppei), Kadokura, A. (Akira), Ozaki, M. (Mitsunori), Yagitani, S. (Satoshi), Shiokawa, K. (Kazuo), Tanaka, Y. (Yoshimasa), Ogawa, Y. (Yasunobu), Hosokawa, K. (Keisuke), Kasahara, Y. (Yoshiya), Ebihara, Y. (Yusuke), Miyoshi, Y. (Yoshizumi), Imamura, K. (Kousuke), Kataoka, R. (Ryuho), Oyama, S.-I. (Shin-Ichiro), Chida, T. (Teppei), and Kadokura, A. (Akira)

Abstract

Flash aurora driven by an isolated chorus element can be a useful ionospheric indicator for identifying the source wave properties via wave-particle interactions. Using ground observation and modeling approaches, here we report the temporal characteristics of flash aurora that depend on the chorus frequency width and the sweep rate. We found that the contraction time increases more than the expansion time in patchy auroral variations, due to the difference in the minimum electron energies resonated with the chorus wave packet away from the equatorial source to higher latitudes. Especially, the contraction time strongly depends on the higher-frequency chorus waves due to cyclotron resonance with lower-energy electrons. The model calculations support that the chorus element ranges from lower-band to upper-band frequencies with respect to half the gyrofrequency at the exact generation region. Our study provides the prompt (milliseconds) chorus-driven electron dynamics through the spatiotemporal characteristics of flash aurora in the ionosphere.

Published
2022

39. The Fermi Gamma-Ray Space Telescope Discovers the Pulsar in the Young Galactic Supernova Remnant CTA 1

Author

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., Silva, E. do Couto 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., and Ziegler, M.

Published
2008
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41. Quantifying the size and duration of a microburst-producing chorus region on 5 December 2017

Author

Elliott, S. S. (S. S.), Breneman, A. W. (A. W.), Colpitts, C. (C.), Pettit, J. M. (J. M.), Cattell, C. A. (C. A.), Halford, A. J. (A. J.), Shumko, M. (M.), Sample, J. (J.), Johnson, A. T. (A. T.), Miyoshi, Y. (Y.), Kasahara, Y. (Y.), Cully, C. M. (C. M.), Nakamura, S. (S.), Mitani, T. (T.), Hori, T. (T.), Shinohara, I. (I.), Shiokawa, K. (K.), Matsuda, S. (S.), Connors, M. (M.), Ozaki, M. (M.), and Manninen, J. (J.)

Subjects
electron precipitation, chorus waves, microburst precipitation, radiation belt, wave-particle interactions
Abstract

Microbursts are impulsive (30 keV) precipitation (FIREBIRD II and AC6 CubeSats, POES) to determine the size of the microburst-producing chorus source region beginning on 5 December 2017. We estimate that the long-lasting (∼30 hr) microburst-producing chorus region extends from 4 to 8 ΔMLT and 2–5 ΔL. We conclude that microbursts likely represent a major loss source of outer radiation belt electrons for this event.

Published
2022

42. Transethnic genome-wide association study provides insights in the genetic architecture and heritability of long QT syndrome

Author

Lahrouchi, N, Tadros, R, Crotti, L, Mizusawa, Y, Postema, P, Beekman, L, Walsh, R, Hasegawa, K, Barc, J, Ernsting, M, Turkowski, K, Mazzanti, A, Beckmann, B, Shimamoto, K, Diamant, U, Wijeyeratne, Y, Kucho, Y, Robyns, T, Ishikawa, T, Arbelo, E, Christiansen, M, Winbo, A, Jabbari, R, Lubitz, S, Steinfurt, J, Rudic, B, Loeys, B, Shoemaker, M, Weeke, P, Pfeiffer, R, Davies, B, Andorin, A, Hofman, N, Dagradi, F, Pedrazzini, M, Tester, D, Bos, J, Sarquella-Brugada, G, Campuzano, Ó, Platonov, P, Stallmeyer, B, Zumhagen, S, Nannenberg, E, Veldink, J, van den Berg, L, Al-Chalabi, A, Shaw, C, Shaw, P, Morrison, K, Andersen, P, Müller-Nurasyid, M, Cusi, D, Barlassina, C, Galan, P, Lathrop, M, Munter, M, Werge, T, Ribasés, M, Aung, T, Khor, C, Ozaki, M, Lichtner, P, Meitinger, T, van Tintelen, J, Hoedemaekers, Y, Denjoy, I, Leenhardt, A, Napolitano, C, Shimizu, W, Schott, J, Gourraud, J, Makiyama, T, Ohno, S, Itoh, H, Krahn, A, Antzelevitch, C, Roden, D, Saenen, J, Borggrefe, M, Odening, K, Ellinor, P, Tfelt-Hansen, J, Skinner, J, van den Berg, M, Olesen, M, Brugada, J, Brugada, R, Makita, N, Breckpot, J, Yoshinaga, M, Behr, E, Rydberg, A, Aiba, T, Kääb, S, Priori, S, Guicheney, P, Tan, H, Newton-Cheh, C, Ackerman, M, Schwartz, P, Schulze-Bahr, E, Probst, V, Horie, M, Wilde, A, Tanck, M, Bezzina, C, Lahrouchi N, Tadros R, Crotti L, Mizusawa Y, Postema PG, Beekman L, Walsh R, Hasegawa K, Barc J, Ernsting M, Turkowski KL, Mazzanti A, Beckmann BM, Shimamoto K, Diamant UB, Wijeyeratne YD, Kucho Y, Robyns T, Ishikawa T, Arbelo E, Christiansen M, Winbo A, Jabbari R, Lubitz SA, Steinfurt J, Rudic B, Loeys B, Shoemaker MB, Weeke PE, Pfeiffer R, Davies B, Andorin A, Hofman N, Dagradi F, Pedrazzini M, Tester DJ, Bos JM, Sarquella-Brugada G, Campuzano Ó, Platonov PG, Stallmeyer B, Zumhagen S, Nannenberg EA, Veldink JH, van den Berg LH, Al-Chalabi A, Shaw CE, Shaw PJ, Morrison KE, Andersen PM, Müller-Nurasyid M, Cusi D, Barlassina C, Galan P, Lathrop M, Munter M, Werge T, Ribasés M, Aung T, Khor CC, Ozaki M, Lichtner P, Meitinger T, van Tintelen JP, Hoedemaekers Y, Denjoy I, Leenhardt A, Napolitano C, Shimizu W, Schott JJ, Gourraud JB, Makiyama T, Ohno S, Itoh H, Krahn AD, Antzelevitch C, Roden DM, Saenen J, Borggrefe M, Odening KE, Ellinor PT, Tfelt-Hansen J, Skinner JR, van den Berg MP, Olesen MS, Brugada J, Brugada R, Makita N, Breckpot J, Yoshinaga M, Behr ER, Rydberg A, Aiba T, Kääb S, Priori SG, Guicheney P, Tan HL, Newton-Cheh C, Ackerman MJ, Schwartz PJ, Schulze-Bahr E, Probst V, Horie M, Wilde AA, Tanck MWT, Bezzina CR., Lahrouchi, N, Tadros, R, Crotti, L, Mizusawa, Y, Postema, P, Beekman, L, Walsh, R, Hasegawa, K, Barc, J, Ernsting, M, Turkowski, K, Mazzanti, A, Beckmann, B, Shimamoto, K, Diamant, U, Wijeyeratne, Y, Kucho, Y, Robyns, T, Ishikawa, T, Arbelo, E, Christiansen, M, Winbo, A, Jabbari, R, Lubitz, S, Steinfurt, J, Rudic, B, Loeys, B, Shoemaker, M, Weeke, P, Pfeiffer, R, Davies, B, Andorin, A, Hofman, N, Dagradi, F, Pedrazzini, M, Tester, D, Bos, J, Sarquella-Brugada, G, Campuzano, Ó, Platonov, P, Stallmeyer, B, Zumhagen, S, Nannenberg, E, Veldink, J, van den Berg, L, Al-Chalabi, A, Shaw, C, Shaw, P, Morrison, K, Andersen, P, Müller-Nurasyid, M, Cusi, D, Barlassina, C, Galan, P, Lathrop, M, Munter, M, Werge, T, Ribasés, M, Aung, T, Khor, C, Ozaki, M, Lichtner, P, Meitinger, T, van Tintelen, J, Hoedemaekers, Y, Denjoy, I, Leenhardt, A, Napolitano, C, Shimizu, W, Schott, J, Gourraud, J, Makiyama, T, Ohno, S, Itoh, H, Krahn, A, Antzelevitch, C, Roden, D, Saenen, J, Borggrefe, M, Odening, K, Ellinor, P, Tfelt-Hansen, J, Skinner, J, van den Berg, M, Olesen, M, Brugada, J, Brugada, R, Makita, N, Breckpot, J, Yoshinaga, M, Behr, E, Rydberg, A, Aiba, T, Kääb, S, Priori, S, Guicheney, P, Tan, H, Newton-Cheh, C, Ackerman, M, Schwartz, P, Schulze-Bahr, E, Probst, V, Horie, M, Wilde, A, Tanck, M, Bezzina, C, Lahrouchi N, Tadros R, Crotti L, Mizusawa Y, Postema PG, Beekman L, Walsh R, Hasegawa K, Barc J, Ernsting M, Turkowski KL, Mazzanti A, Beckmann BM, Shimamoto K, Diamant UB, Wijeyeratne YD, Kucho Y, Robyns T, Ishikawa T, Arbelo E, Christiansen M, Winbo A, Jabbari R, Lubitz SA, Steinfurt J, Rudic B, Loeys B, Shoemaker MB, Weeke PE, Pfeiffer R, Davies B, Andorin A, Hofman N, Dagradi F, Pedrazzini M, Tester DJ, Bos JM, Sarquella-Brugada G, Campuzano Ó, Platonov PG, Stallmeyer B, Zumhagen S, Nannenberg EA, Veldink JH, van den Berg LH, Al-Chalabi A, Shaw CE, Shaw PJ, Morrison KE, Andersen PM, Müller-Nurasyid M, Cusi D, Barlassina C, Galan P, Lathrop M, Munter M, Werge T, Ribasés M, Aung T, Khor CC, Ozaki M, Lichtner P, Meitinger T, van Tintelen JP, Hoedemaekers Y, Denjoy I, Leenhardt A, Napolitano C, Shimizu W, Schott JJ, Gourraud JB, Makiyama T, Ohno S, Itoh H, Krahn AD, Antzelevitch C, Roden DM, Saenen J, Borggrefe M, Odening KE, Ellinor PT, Tfelt-Hansen J, Skinner JR, van den Berg MP, Olesen MS, Brugada J, Brugada R, Makita N, Breckpot J, Yoshinaga M, Behr ER, Rydberg A, Aiba T, Kääb S, Priori SG, Guicheney P, Tan HL, Newton-Cheh C, Ackerman MJ, Schwartz PJ, Schulze-Bahr E, Probst V, Horie M, Wilde AA, Tanck MWT, and Bezzina CR.

Abstract

Background: Long QT syndrome (LQTS) is a rare genetic disorder and a major preventable cause of sudden cardiac death in the young. A causal rare genetic variant with large effect size is identified in up to 80% of probands (genotype positive) and cascade family screening shows incomplete penetrance of genetic variants. Furthermore, a proportion of cases meeting diagnostic criteria for LQTS remain genetically elusive despite genetic testing of established genes (genotype negative). These observations raise the possibility that common genetic variants with small effect size contribute to the clinical picture of LQTS. This study aimed to characterize and quantify the contribution of common genetic variation to LQTS disease susceptibility. Methods: We conducted genome-wide association studies followed by transethnic meta-analysis in 1656 unrelated patients with LQTS of European or Japanese ancestry and 9890 controls to identify susceptibility single nucleotide polymorphisms. We estimated the common variant heritability of LQTS and tested the genetic correlation between LQTS susceptibility and other cardiac traits. Furthermore, we tested the aggregate effect of the 68 single nucleotide polymorphisms previously associated with the QT-interval in the general population using a polygenic risk score. Results: Genome-wide association analysis identified 3 loci associated with LQTS at genome-wide statistical significance (P5×10-8) near NOS1AP, KCNQ1, and KLF12, and 1 missense variant in KCNE1(p.Asp85Asn) at the suggestive threshold (P10-6). Heritability analyses showed that ≈15% of variance in overall LQTS susceptibility was attributable to common genetic variation (h2SNP 0.148; standard error 0.019). LQTS susceptibility showed a strong genome-wide genetic correlation with the QT-interval in the general population (rg=0.40; P=3.2×10-3). The polygenic risk score comprising common variants previously associated with the QT-interval in the general population was greater in LQTS c

Published
2020

45. Safer (but not better) imaging

Author

Ellis Stephen, Itoh S, Koyama S, Ikeda M, Ozaki M, Sawaki A, Iwano S, and Ishigaki T

Subjects
Cancer, CT, screening, Diseases of the respiratory system, RC705-779
Published
2001
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49. Over-darkening of pulsating aurora

Author

Hosokawa, K. (K.), Miyoshi, Y. (Y.), Oyama, S.-I. (S.-I.), Ogawa, Y. (Y.), Kurita, S. (S.), Kasahara, Y. (Y.), Kasaba, Y. (Y.), Yagitani, S. (S.), Matsuda, S. (S.), Ozaki, M. (M.), Tsuchiya, F. (F.), Kumamoto, A. (A.), Takashima, T. (T.), Shinohara, I. (I.), and Fujii, R. (R.)

Subjects
wave particle interaction, fungi, pulsating aurora, chorus wave, urologic and male genital diseases
Abstract

Recent analyses of high-time resolution ground-based optical observations of pulsating aurora (PsA) have reported that the brightness of PsA sometimes decreases below the diffuse background level immediately after the ON phase of the main pulsation finishes. To date, however, the generation mechanism of such an “over-darkening PsA” is still unclarified. In this study, we investigated the characteristics of the over-darkening PsA by using simultaneous observations of PsA with an electron multiplying charge coupled device all-sky camera in Sodankylä, Finland and the Arase satellite. During one of the conjunction events in Scandinavia on March 29, 2017, almost all the PsA pulses showed clear over-darkening characteristics. By analyzing the 2D all-sky images at the times of over-darkening we discovered that over-darkening areas appeared in the trailing edge of PsA patches and moved in tandem with the poleward propagating patches. It was also found that similar over-decreasing characteristics were not seen in the chorus data from the wave instruments onboard Arase located at the magnetospheric counterpart of PsA. These results indicate that the over-darkening PsA is not caused by a temporal variation of chorus at a fixed point, but is produced by a propagation of over-darkening area with PsA patches. That is, the over-darkening PsA is a result of compounding effects of spatial structure and recurrent propagation of PsA. The mechanism creating the dark area is still unknown, but the existence of over-darkening PsA suggests that the temporal variation of PsA is not always a perfect copy of the modulation of lower-band chorus waves in the magnetosphere.

Published
2021

50. Magnetic conjugacy of Pc1 waves and isolated proton precipitation at subauroral latitudes: Importance of ionosphere as intensity modulation region

Author

Ozaki, M., Shiokawa, K., Horne, R.B., Engebretson, M.K., Lessard, M., Ogawa, Y., Hosokawa, K., Nose, M., Ebihara, Y., Kadokura, A., Yagitani, S., Miyoshi, Y., Hashimoto, S., Sinha, S., Sinha, A.K., Seemala, G.K., Jun, C.-W., Ozaki, M., Shiokawa, K., Horne, R.B., Engebretson, M.K., Lessard, M., Ogawa, Y., Hosokawa, K., Nose, M., Ebihara, Y., Kadokura, A., Yagitani, S., Miyoshi, Y., Hashimoto, S., Sinha, S., Sinha, A.K., Seemala, G.K., and Jun, C.-W.

Abstract

Pc1 geomagnetic pulsations, equivalent to electromagnetic ion cyclotron waves in the magnetosphere, display a specific amplitude modulation, though the region of the modulation remains an open issue. To classify whether the amplitude modulation has a magnetospheric or ionospheric origin, an isolated proton aurora (IPA), which is a proxy of Pc1 wave–particle interactions, is compared with the associated Pc1 waves for a geomagnetic conjugate pair, Halley Research Base in Antarctica and Nain in Canada. The temporal variation of an IPA shows a higher correlation coefficient (0.88) with Pc1 waves in the same hemisphere than that in the opposite hemisphere. This conjugate observation reveals that the classic cyclotron resonance is insufficient to determine the amplitude modulation. We suggest that direct wave radiation from the ionospheric current by IPA should also contribute to the amplitude modulation.

Published
2021

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