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88 results on '"Yonetoku, Daisuke"'

3. The Density and Ionization Profiles of Optically Dark and High-Redshift GRBs Probed by X-ray Absorption.

Author

Arumaningtyas, Eka Puspita, Al Rasyid, Hasan, Dainotti, Maria Giovanna, and Yonetoku, Daisuke

Subjects
DISTRIBUTION (Probability theory), INTERSTELLAR medium, X-ray spectra, PHOTON flux, X-ray absorption, GAMMA ray bursts, REDSHIFT
Abstract

The X-ray column density ( N HX ) of gamma-ray bursts (GRBs) can probe the local environment of their progenitors over a wide redshift range. Previous work has suggested an increasing trend as a function of redshift. The relevance of this current analysis relies on investigating the selection bias method, such as the effect of the X-ray spectrum in high-redshift GRBs, which complicates the measurement of small N HX ; this has yet to be fully evaluated or discussed elsewhere. In this work, we evaluated these effects through simulations to define appropriate observational limits in the N HX versus redshift plane. We then applied a one-sided nonparametric method developed by Efron and Petrosian. Within the framework of this method, we investigated the redshift dependence of N HX and the local distribution function. Our results show that the evolution of N HX with redshift firmly exists with a significance of more than four sigma and follows a power law of (1 + z) 1.39 (+ 0.22 , − 0.27) . Based on these analyses and previous studies, the GRB progenitor mass varies but is more massive in the high-redshift environment and has a higher gas column density. This suggests that part of the luminosity evolution of GRBs, which has been widely reported, may be due to the evolution of the progenitor's mass. Using the same method, we demonstrate that optically dark GRBs show a consistent evolution: (1 + z) 1.15 (+ 0.67 , − 0.83) . By applying the Kolmogorov–Smirnov (KS) test, it is shown that optically dark GRBs have statistically identical flux and photon index distributions compared to normal GRBs, but the N HX is systematically larger. This result suggests that the darkness of some GRB populations is not due to an intrinsic mechanism, but rather because a higher density surrounds them. [ABSTRACT FROM AUTHOR]

Published
2024
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5. Peak energy–isotropic luminosity correlation and jet opening angle evolution in Swift-BAT short GRBs with soft-tail emission.

Author

Ogino, Naoki, Yonetoku, Daisuke, Arimoto, Makoto, Sawano, Tatsuya, and Hamidani, Hamid

Subjects
*GAMMA ray bursts, *LUMINOSITY, *ANGLES, *TIMEKEEPING, *GRAVITATIONAL waves, *REDSHIFT
Abstract

Some short gamma-ray bursts (SGRBs) exhibit a short-duration and spectral hard emission (referred to as a "hard spike") followed by a slightly longer soft emission (known as a "soft tail"). We identified nine SGRBs with the known redshift in the Swift/BAT gamma-ray burst catalog by specifically searching for the soft tail. We found that the spectra of these SGRBs can be described as a cutoff power-law model for the hard spike and the soft tail, and both show a time variation keeping the E peak– L iso correlation. This suggests that the emission mechanisms of both phenomena are identical. Furthermore, we found a trend of luminosity evolution as a function of redshift. This phenomenon suggests that these bursts originate from sources that are intrinsically bright and/or energy-density-concentrated within a narrower jet at higher redshift. We demonstrate that the average jet opening angle, derived from the jet break, can be explained by considering a model based on a strongly redshift-dependent jet opening angle. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Possible X-ray cocoon emission from GRB 050709.

Author

Ogino, Naoki, Arimoto, Makoto, Hamidani, Hamid, Sakamoto, Takanori, Yonetoku, Daisuke, Sawano, Tatsuya, Serino, Motoko, Asano, Katsuaki, and Kawai, Nobuyuki

Subjects
COCOONS, X-rays, GAMMA ray bursts, GRAVITATIONAL waves
Abstract

The detection of the short gamma-ray burst (SGRB) 050709 by the HETE-2 satellite opened the door to understanding the nature of SGRBs, offering clues about their emission mechanism and progenitors, with the crucial aid of optical follow-up observations. Here, we revisit the prompt emission of GRB 050709. Our analysis reveals an initial hard spike ∼200 ms long, followed by a subsequent soft-tail emission lasting ∼300 ms. These components could be common among other SGRBs originating from binary neutron merger events, such as GW 170817 and GRB 170817A. Detailed temporal and spectral analyses indicate that the soft-tail emission might be attributed to the cocoon formed by the relativistic jet depositing energy into the surrounding material. We find the necessary cocoon parameters at the breakout, as consistent with numerical simulation results. We compared the physical parameters of this cocoon with those of other SGRBs. The relatively higher cocoon pressure and temperature in GRB 050709 may indicate a more on-axis jet compared with GRB 170817A and GRB 150101B. [ABSTRACT FROM AUTHOR]

Published
2024
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7. Numerical simulation of photospheric emission in long gamma-ray bursts: prompt correlations, spectral shapes, and polarizations

Author

Ito, Hirotaka, Matsumoto, Jin, Nagataki, Shigehiro, Warren, Donald C., Barkov, Maxim V., and Yonetoku, Daisuke

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), FOS: Physical sciences, Astrophysics - High Energy Astrophysical Phenomena
Abstract

We explore the properties of photospheric emission in the context of long gamma-ray bursts (LGRBs) using three numerical models that combine relativistic hydrodynamical simulations and Monte Carlo radiation transfer calculations in three dimensions. Our simulations confirm that the photospheric emission gives rise to correlations between the spectral peak energy and luminosity that agree with the observed Yonetoku, Amati, and Golenetskii correlations. It is also shown that the spectral peak energy and luminosity correlate with the bulk Lorentz factor, as indicated in the literature. On the other hand, synthetic spectral shapes tend to be narrower than those of the observations. The result indicates that an additional physical process that can provide non-thermal broadening is needed to reproduce the spectral features. Furthermore, the polarization analysis finds that, while the degree of polarization is low for the emission from the jet core ($\Pi < 4~\%$), it tends to increase with the viewing angle outside the core and can be as high as $\Pi \sim 20-40~\%$ in an extreme case. This suggests that the typical GRBs show systematically low polarization compared to softer, dimmer counterparts (X-ray-rich GRBs and X-ray flashes). Interestingly, our simulations indicate that photospheric emission exhibits large temporal variation in the polarization position angle ($\Delta \psi \sim 90^{\circ}$), which may be compatible with those inferred in observations. A notable energy dependence of the polarization property is another characteristic feature found in the current study. Particularly, the difference in the position angle among different energy bands can be as large as $\sim 90^{\circ}$., Comment: 20 pages, 12 figures, accepted for publication in ApJ

Published
2023

8. Gamma-ray glow preceding downward terrestrial gamma-ray flash

Author

Wada, Yuuki, Enoto, Teruaki, Nakamura, Yoshitaka, Furuta, Yoshihiro, Yuasa, Takayuki, Nakazawa, Kazuhiro, Morimoto, Takeshi, Sato, Mitsuteru, Matsumoto, Takahiro, Yonetoku, Daisuke, Sawano, Tatsuya, Sakai, Hideo, Kamogawa, Masashi, Ushio, Tomoo, Makishima, Kazuo, and Tsuchiya, Harufumi

Published
2019
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11. Temperature Structure in the Perseus Cluster Core Observed with Hitomi

Author

Aharonian, Felix, Akamatsu, Hiroki, Akimoto, Fumie, Allen, Steven W, Angelini, Lorella, Audard, Marc, Awaki, Hisamitsu, Axelsson, Magnus, Bamba, Aya, Bautz, Marshall W, Blandford, Roger, Brenneman, Laura W, Brown, Gregory V, Bulbul, Esra, Cackett, Edward M, Chernyakova, Maria, Chiao, Meng P, Coppi, Paolo S, Costantini, Elisa, Plaa, Jelle De, Vries, Cor P. De, Den Herder, Jan-Willem, Done, Chris, Dotani, Tadayasu, Ebisawa, Ken, Eckart, Megan E, Enoto, Teruaki, Ezoe, Yuichiro, Fabian, Andrew C, Ferrigno, Carlo, Foster, Adam R, Fujimoto, Ryuichi, Fukazawa, Yasushi, Furukawa, Maki, Furuzawa, Akihiro, Galeazzi, Massimiliano, Gallo, Luigi C, Gandhi, Poshak, Giustini, Margherita, Goldwurm, Andrea, Gu, Liyi, Guainazzi, Matteo, Haba, Yoshito, Hagino, Kouichi, Hamaguchi, Kenji, Harrus, Ilana M, Hatsukade, Isamu, Hayashi, Katsuhiro, Hayashi, Takayuki, Hayashida, Kiyoshi, Hiraga, Junko S, Hornschemeier, Ann, Hoshino, Akio, Hughes, John P, Ichinohe, Yuto, Iizuka, Ryo, Inoue, Hajime, Inoue, Yoshiyuki, Ishida, Manabu, Ishikawa, Kumi, Ishisaki, Yoshitaka, Iwai, Masachika, Kaastra, Jelle, Kallman, Tim, Kamae, Tsuneyoshi, Kataoka, Jun, Kato, Yuichi, Katsuda, Satoru, Kawai, Nobuyuki, Kelley, Richard L, Kilbourne, Caroline A, Kitaguchi, Takao, Kitamoto, Shunji, Kitayama, Tetsu, Kohmura, Takayoshi, Kokubun, Motohide, Koyama, Katsuji, Koyama, Shu, Kretschmar, Peter, Krimm, Hans A, Kubota, Aya, Kunieda, Hideyo, Laurent, Philippe, Lee, Shiu-Hang, Leutenegger, Maurice A, Limousin, Olivier, Loewenstein, Michael, Long, Knox S, Lumb, David, Madejski, Greg, Maeda, Yoshitomo, Maier, Daniel, Makishima, Kazuo, Markevitch, Maxim, Matsumoto, Hironori, Matsushita, Kyoko, Mccammon, Dan, Mcnamara, Brian R, Mehdipour, Missagh, Miller, Eric D, Miller, Jon M, Mineshige, Shin, Mitsuda, Kazuhisa, Mitsuishi, Ikuyuki, Miyazawa, Takuya, Mizuno, Tsunefumi, Mori, Hideyuki, Mori, Koji, Mukai, Koji, Murakami, Hiroshi, Mushotzky, Richard F, Nakagawa, Takao, Nakajima, Hiroshi, Nakamori, Takeshi, Nakashima, Shinya, Nakazawa, Kazuhiro, Nobukawa, Kumiko K, Nobukawa, Masayoshi, Noda, Hirofumi, Odaka, Hirokazu, Ohashi, Takaya, Ohno, Masanori, Okajima, Takashi, Ota, Naomi, Ozaki, Masanobu, Paerels, Frits, Altani, Stephane P ´, Petre, Robert, Pinto, Ciro, Porter, Frederick S, Pottschmidt, Katja, Reynolds, Christopher S, Safi-Harb, Samar, Saito, Shinya, Sakai, Kazuhiro, Sasaki, Toru, Sato, Goro, Sato, Kosuke, Sato, Rie, Sawada, Makoto, Schartel, Norbert, Serlemtsos, Peter J, Seta, Hiromi, Shidatsu, Megumi, Simionescu, Aurora, Smith, Randall K, Soong, Yang, Stawarz, Łukasz, Sugawara, Yasuharu, Sugita, Satoshi, Szymkowiak, Andrew, Tajima, Hiroyasu, Takahashi, Hiromitsu, Takahashi, Tadayuki, Takeda, Shin´Ichiro, Takei, Yoh, Tamagawa, Toru, Tamura, Takayuki, Tanaka, Takaaki, Tanaka, Yasuo, Tanaka, Yasuyuki T, Tashiro, Makoto S, Tawara, Yuzuru, Terada, Yukikatsu, Terashima, Yuichi, Tombesi, Francesco, Tomida, Hiroshi, Tsuboi, Yohko, Tsujimoto, Masahiro, Tsunemi, Hiroshi, Tsuru, Takeshi Go, Uchida, Hiroyuki, Uchiyama, Hideki, Uchiyama, Yasunobu, Ueda, Shutaro, Ueda, Yoshihiro, Uno, Shin´Ichiro, Urry, C. Megan, Ursino, Eugenio, Watanabe, Shin, Werner, Norbert, Wilkins, Dan R, Williams, Brian J, Yamada, Shinya, Yamaguchi, Hiroya, Yamaoka, Kazutaka, Yamauchi, Noriko Y. Yamasaki 22. Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yatsu, Yoichi, Yonetoku, Daisuke, Zhuravleva, Irina, and Zoghbi, Abderahmen

Subjects
Astrophysics
Abstract

The present paper investigates the temperature structure of the X-ray emitting plasma in the core of the Perseus cluster using the 1.8-20.0 keV data obtained with the Soft X-ray Spectrometer (SXS) onboard the Hitomi Observatory. A series of four observations were carried out, with a total effective exposure time of 338 ks and covering a central region _ 7′ in diameter. The SXS was operated with an energy resolution of _5 eV (full width at half maximum) at 5.9 keV. Not only fine structures of K-shell lines in He-like ions but also transitions from higher principal quantum numbers are clearly resolved from Si through Fe. This enables us to perform temperature diagnostics using the line ratios of Si, S, Ar, Ca, and Fe, and to provide the first direct measurement of the excitation temperature and ionization temperature in the Perseus cluster. The observed spectrum is roughly reproduced by a single temperature thermal plasma model in collisional ionization equilibrium, but detailed line ratio diagnostics reveal slight deviations from this approximation. In particular, the data exhibit an apparent trend of increasing ionization temperature with increasing atomic mass, as well as small differences between the ionization and excitation temperatures for Fe, the only element for which both temperatures can be measured. The best-fit two-temperature models suggest a combination of 3 and 5 keV gas, which is consistent with the idea that the observed small deviations from a single temperature approximation are due to the effects of projection of the known radial temperature gradient in the cluster core along the line of sight. Comparison with the Chandra/ACIS and the XMM-Newton/RGS results on the other hand suggests that additional lower-temperature components

Published
2018
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12. Solar abundance ratios of the iron-peak elements in the Perseus cluster

Author

Aharonian, Felix, Akamatsu, Hiroki, Akimoto, Fumie, Allen, Steven W., Angelini, Lorella, Audard, Marc, Awaki, Hisamitsu, Axelsson, Magnus, Bamba, Aya, Bautz, Marshall W., Blandford, Roger, Brenneman, Laura W., Brown, Gregory V., Bulbul, Esra, Cackett, Edward M., Chernyakova, Maria, Chiao, Meng P., Coppi, Paolo S., Costantini, Elisa, de Plaa, Jelle, den Herder, Jan-Willem, Done, Chris, Dotani, Tadayasu, Ebisawa, Ken, Eckart, Megan E., Enoto, Teruaki, Ezoe, Yuichiro, Fabian, Andrew C., Ferrigno, Carlo, Foster, Adam R., Fujimoto, Ryuichi, Fukazawa, Yasushi, Furuzawa, Akihiro, Galeazzi, Massimiliano, Gallo, Luigi C., Gandhi, Poshak, Giustini, Margherita, Goldwurm, Andrea, Gu, Liyi, Guainazzi, Matteo, Haba, Yoshito, Hagino, Kouichi, Hamaguchi, Kenji, Harrus, Ilana M., Hatsukade, Isamu, Hayashi, Katsuhiro, Hayashi, Takayuki, Hayashida, Kiyoshi, Hiraga, Junko S., Hornschemeier, Ann, Hoshino, Akio, Hughes, John P., Ichinohe, Yuto, Iizuka, Ryo, Inoue, Hajime, Inoue, Yoshiyuki, Ishida, Manabu, Ishikawa, Kumi, Ishisaki, Yoshitaka, Iwai, Masachika, Kaastra, Jelle, Kallman, Tim, Kamae, Tsuneyoshi, Kataoka, Jun, Katsuda, Satoru, Kawai, Nobuyuki, Kelley, Richard L., Kilbourne, Caroline A., Kitaguchi, Takao, Kitamoto, Shunji, Kitayama, Tetsu, Kohmura, Takayoshi, Kokubun, Motohide, Koyama, Katsuji, Koyama, Shu, Kretschmar, Peter, Krimm, Hans A., Kubota, Aya, Kunieda, Hideyo, Laurent, Philippe, Lee, Shiu-Hang, Leutenegger, Maurice A., Limousine, Olivier, Loewenstein, Michael, Long, Knox S., Lumb, David, Madejski, Greg, Maeda, Yoshitomo, Maier, Daniel, Makishima, Kazuo, Markevitch, Maxim, Matsumoto, Hironori, Matsushita, Kyoko, McCammon, Dan, McNamara, Brian R., Mehdipour, Missagh, Miller, Eric D., Miller, Jon M., Mineshige, Shin, Mitsuda, Kazuhisa, Mitsuishi, Ikuyuki, Miyazawa, Takuya, Mizuno, Tsunefumi, Mori, Hideyuki, Mori, Koji, Mukai, Koji, Murakami, Hiroshi, Mushotzky, Richard F., Nakagawa, Takao, Nakajima, Hiroshi, Nakamori, Takeshi, Nakashima, Shinya, Nakazawa, Kazuhiro, Nobukawa, Kumiko K., Nobukawa, Masayoshi, Noda, Hirofumi, Odaka, Hirokazu, Ohashi, Takaya, Ohno, Masanori, Okajima, Takashi, Ota, Naomi, Ozaki, Masanobu, Paerels, Frits, Paltani, Stéphane, Petre, Robert, Pinto, Ciro, Porter, Frederick S., Pottschmidt, Katja, Reynolds, Christopher S., Safi-Harb, Samar, Saito, Shinya, Sakai, Kazuhiro, Sasaki, Toru, Sato, Goro, Sato, Kosuke, Sato, Rie, Sawada, Makoto, Schartel, Norbert, Serlemitsos, Peter J., Seta, Hiromi, Shidatsu, Megumi, Simionescu, Aurora, Smith, Randall K., Soong, Yang, Stawarz, Lukasz, Sugawara, Yasuharu, Sugita, Satoshi, Szymkowiak, Andrew, Tajima, Hiroyasu, Takahashi, Hiromitsu, Takahashi, Tadayuki, Takeda, Shinʼichiro, Takei, Yoh, Tamagawa, Toru, Tamura, Takayuki, Tanaka, Takaaki, Tanaka, Yasuo, Tanaka, Yasuyuki T., Tashiro, Makoto S., Tawara, Yuzuru, Terada, Yukikatsu, Terashima, Yuichi, Tombesi, Francesco, Tomida, Hiroshi, Tsuboi, Yohko, Tsujimoto, Masahiro, Tsunemi, Hiroshi, Go Tsuru, Takeshi, Uchida, Hiroyuki, Uchiyama, Hideki, Uchiyama, Yasunobu, Ueda, Shutaro, Ueda, Yoshihiro, Uno, Shinʼichiro, Urry, Megan C., Ursino, Eugenio, de Vries, Cor P., Watanabe, Shin, Werner, Norbert, Wik, Daniel R., Wilkins, Dan R., Williams, Brian J., Yamada, Shinya, Yamaguchi, Hiroya, Yamaoka, Kazutaka, Yamasaki, Noriko Y., Yamauchi, Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yatsu, Yoichi, Yonetoku, Daisuke, Zhuravleva, Irina, and Zoghbi, Abderahmen

Published
2017
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13. The ASTRO-H (Hitomi) X-Ray Astronomy Satellite

Author

Takahashi, Tadayuki, Kokubun, Motohide, Mitsuda, Kazuhisa, Kelley, Richard, Ohashi, Takaya, Aharonian, Felix, Akamatsu, Hiroki, Akimoto, Fumie, Allen, Steve, Anabuki, Naohisa, Angelini, Lorella, Arnaud, Keith, Asai, Makoto, Audard, Marc, Awaki, Hisamitsu, Axelsson, Magnus, Azzarello, Philipp, Baluta, Chris, Bamba, Aya, Bando, Nobutaka, Bautz, Marshall, Bialas, Thomas, Blandford, Roger, Boyce, Kevin, Brenneman, Laura, Brown, Greg, Bulbul, Esra, Cackett, Edward, Canavan, Edgar, Chernyakova, Maria, Chiao, Meng, Coppi, Paolo, Costantini, Elisa, De Plaa, Jelle, Den Herder, Jan-Willem, DiPirro, Michael, Done, Chris, Dotani, Tadayasu, Doty, John, Ebisawa, Ken, Eckart, Megan, Enoto, Teruaki, Ezoe, Yuichiro, Fabian, Andrew, Ferrigno, Carlo, Foster, Adam, Fujimoto, Ryuichi, Fukazawa, Yasushi, Furuzawa, Akihiro, Galeazzi, Massimiliano, Gallo, Luigi, Gandhi, Poshak, Gilmore, Kirk, Giustini, Margherita, Goldwurm, Andrea, Gu, Liyi, Guainassi, Matteo, Haas, Daniel, Haba, Yoshito, Hagino, Kouichi, Hamaguchi, Kenji, Harayama, Atsushi, Harrus, Ilana, Hatsukade, Isamu, Hayashi, Takayuki, Hayashi, Katsuhiro, Hayashida, Kiyoshi, Hiraga, Junko, Hirose, Kazuyuki, Hornschemeier, Ann, Hoshino, Akio, Hughes, John, Ichinohe, Yuto, Iizuka, Ryo, Inoue, Yoshiyuki, Inoue, Hajime, Ishibashi, Kazunori, Ishida, Manabu, Ishikawa, Kumi, Ishimura, Kosei, Ishisaki, Yoshitaka, Itoh, Masayuki, Iwata, Naoko, Iyomoto, Naoko, Jewell, Chris, Kaastra, Jelle, Kallman, Timothy, Kamae, Tuneyoshi, Kara, Erin, Kataoka, Jun, Katsuda, Satoru, Katsuta, Junichiro, Kawaharada, Madoka, Kawai, Nobuyuki, Kawano, Taro, Kawasaki, Shigeo, Khangulyan, Dmitry, Kilbourne, Caroline, Kimball, Mark, King, Ashley, Kitaguchi, Takao, Kitamoto, Shunji, Kitayama, Tetsu, Kohmura, Takayoshi, Kosaka, Tatsuro, Koujelev, Alex, Koyama, Katsuji, Koyama, Shu, Kretschmar, Peter, Krimm, Hans, Kubota, Aya, Kunieda, Hideyo, Laurent, Philippe, Lebrun, Francois, Lee, Shiu-Hang, Leutenegger, Maurice, Limousin, Olivier, Loewenstein, Michael, Long, Knox, Lumb, David, Madejski, Grzegorz, Maeda, Yoshitomo, Maier, Daniel, Makishima, Kazuo, Markevitch, Maxim, Matsumoto, Hironori, Matsushita, Kyoko, McCammon, Dan, McNamara, Brian, Masters, Candace, McGuinness, Daniel, Mehdipour, Missagh, Miko, Joseph, Miller, Jon, Miller, Eric, Mineshige, Shin, Minesugi, Kenji, Mitsuishi, Ikuyuki, Miyazawa, Takuya, Mizuno, Tsunefumi, Mori, Koji, Mori, Hideyuki, Moroso, Franco, Moseley, Harvey, Muench, Theodore, Mukai, Koji, Murakami, Hiroshi, Murakami, Toshio, Mushotzky, Richard, Nagano, Housei, Nagino, Ryo, Nakagawa, Takao, Nakajima, Hiroshi, Nakamori, Takeshi, Nakano, Toshio, Nakashima, Shinya, Nakazawa, Kazuhiro, Namba, Oshiharu, Natsukari, Chikara, Nishioka, Yusuke, Nobukawa, Masayoshi, Noda, Hirofumi, Nobukawa, Kumiko, Nomachi, Masaharu, O'Dell, Steve, Odaka, Hirokazu, Ogawa, Hiroyuki, Ogawa, Mina, Ogi, Keiji, Ohno, Masanori, Ohta, Masayuki, Okajima, Takashi, Okamoto, Atsushi, Okazaki, Tsuyoshi, Ota, Naomi, Ozaki, Masanobu, Paerels, Frits, Paltani, Stephane, Parmar, Arvind, Petre, Robert, Pinto, Ciro, Pohl, Martin, Pontius, James, Porter, F. Scott, Pottschmidt, Katja, Ramsey, Brian, Reynolds, Christopher, Russell, Helen, Safi-Harb, Samar, Saito, Shinya, Sakai, Shin-ichiro, Sakai, Kazuhiro, Sameshima, Hiroaki, Sasaki, Toru, Sato, Goro, Sato, Yoichi, Sato, Kosuke, Sato, Rie, Sawada, Makoto, Schartel, Norbert, Serlemitsos, Peter, Seta, Hiromi, Shibano, Yasuko, Shida, Maki, Shidatsu, Megumi, Shimada, Takanobu, Shinozaki, Keisuke, Shirron, Peter, Simionescu, Aurora, Simmons, Cynthia, Smith, Randall, Sneiderman, Gary, Soong, Yang, Stawarz, Lukasz, Sugawara, Yasuharu, Sugita, Hiroyuki, Sugita, Satoshi, Szymkowiak, Andrew, Tajima, Hiroyasu, Takahashi, Hiromitsu, Takeda, Shin'ichiro, Takei, Yoh, Tamagawa, Toru, Tamura, Takayuki, Tamura, Keisuke, Tanaka, Takaaki, Tanaka, Yasuo, Tanaka, Yasuyuki, Tashiro, Makoto, Tawara, Yuzuru, Terada, Yukikatsu, Terashima, Yuichi, Tombesi, Francesco, Tomida, Hiroshi, Tsuboi, Yohko, Tsujimoto, Masahiro, Tsunemi, Hiroshi, Tsuru, Takeshi, Uchida, Hiroyuki, Uchiyama, Yasunobu, Uchiyama, Hideki, Ueda, Yoshihiro, Ueda, Shutaro, Ueno, Shiro, Uno, Shin'ichiro, Urry, Meg, Ursino, Eugenio, de Vries, Cor, Wada, Atsushi, Watanabe, Shin, Watanabe, Tomomi, Werner, Norbert, Wik, Daniel, Wilkins, Dan, Williams, Brian, Yamada, Takahiro, Yamada, Shinya, Yamaguchi, Hiroya, Yamaoka, Kazutaka, Yamasaki, Noriko, Yamauchi, Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yonetoku, Daisuke, Yoshida, Atsumasa, Yuasa, Takayuki, Zhuravleva, Irina, and Zoghbi, Abderahmen

Subjects
Astrophysics
Abstract

The Hitomi (ASTRO-H) mission is the sixth Japanese X-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E greater than 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft X-rays to gamma-rays. After a successful launch on 2016 February 17, the spacecraft lost its function on 2016 March 26, but the commissioning phase for about a month provided valuable information on the on-board instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month.

Published
2016
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14. Catalog of Gamma-ray Glows during Four Winter Seasons in Japan

Author

Wada, Yuuki, Matsumoto, Takahiro, Enoto, Teruaki, Nakazawa, Kazuhiro, Yuasa, Takayuki, Furuta, Yoshihiro, Yonetoku, Daisuke, Sawano, Tatsuya, Okada, Go, Nanto, Hidehito, Hisadomi, Shohei, Tsuji, Yuna, Diniz, Gabriel Sousa, Makishima, Kazuo, and Tsuchiya, Harufumi

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Physics - Atmospheric and Oceanic Physics, Atmospheric and Oceanic Physics (physics.ao-ph), FOS: Physical sciences, Astrophysics - High Energy Astrophysical Phenomena
Abstract

In 2015 the Gamma-Ray Observation of Winter Thunderstorms (GROWTH) collaboration launched a mapping observation campaign for high-energy atmospheric phenomena related to thunderstorms and lightning discharges. This campaign has developed a detection network of gamma rays with up to 10 radiation monitors installed in Kanazawa and Komatsu cities, Ishikawa Prefecture, Japan, where low-charge-center winter thunderstorms frequently occur. During four winter seasons from October 2016 to April 2020, in total 70 gamma-ray glows, minute-lasting bursts of gamma rays originating from thunderclouds, were detected. Their average duration is 58.9 sec. Among the detected events, 77% were observed in nighttime. The gamma-ray glows can be classified into temporally-symmetric, temporally-asymmetric, and lightning-terminated types based on their count-rate histories. An averaged energy spectrum of the gamma-ray glows is well fitted with a power-law function with an exponential cutoff, whose photon index, cutoff energy, and flux are $0.613\pm0.009$, $4.68\pm0.04$ MeV, and $(1.013\pm0.003)\times10^{-5}$ erg cm$^{-2}$ s$^{-1}$ (0.2-20.0MeV), respectively. The present paper provides the first catalog of gamma-ray glows and their statistical analysis detected during winter thunderstorms in the Kanazawa and Komatsu areas., 34 pages, 29 figures, accepted for publication in Physical Review Research

Published
2021

15. Development of a Monte Carlo simulator for the Astro-E2 hard X-ray detector (HXD-II)

Author

Terada, Yukikatsu, Watanabe, Shin, Ohno, Masanori, Suzuki, Masaya, Itoh, Takeshi, Takahashi, Isao, Sato, Goro, Murashima, Mio, Kawano, Naomi, Uchiyama, Yasunobu, Kubo, Shin, Takahashi, Tadayuki, Tashiro, Makoto, Kokubun, Motohide, Makishima, Kazuo, Kamae, Tsuneyoshi, Murakami, Toshio, Nomachi, Masaharu, Fukazawa, Yasushi, Yamaoka, Kazutaka, Nakazawa, Kazuhiro, and Yonetoku, Daisuke

Subjects
Gamma rays -- Research, Artificial satellites -- Research, Detectors -- Research, Monte Carlo method -- Research, Business, Electronics, Electronics and electrical industries
Abstract

The Hard X-ray Detector (HXD-II) is one of the scientific payloads on board the fifth Japanese cosmic X-ray satellite Astro-E2, scheduled for launch in 2005. The HXD-II is designed to cover a wide energy range of 10-600 keV with a high sensitivity of about [10.sup.-5] cnt/s/[cm.sup.2]/keV. In order to derive the energy response of the sensor and to estimate the background, a Monte Carlo simulator based on the Geant4 toolkit is currently being developed. This paper describes the design concept of the HXD-II software package, including the analysis tools and the Monte Carlo simulator, and its verification through a comparison with actual data taken by pre-flight radio-isotope irradiation experiments, together with calculated outputs that can demonstrate the in-orbit performance of the HXD-II. Index Terms--Astronomical satellites, gamma-ray spectroscopy detectors, Monte Carlo, simulation.

Published
2005

16. Design and performance of Soft Gamma-ray Detector onboard the Hitomi (ASTRO-H) satellite

Author

Blandford, Roger, Goldwurm, Andrea, Laurent, Philippe, Lebrun, Francois, Limousin, Olivier, Madejski, Grzegorz, Tajima, Hiroyasu, Watanabe, Shin, Fukazawa, Yasushi, Enoto, Teruaki, Hagino, Kouichi, Hayashi, Katsuhiro, Ichinohe, Yuto, Kataoka, Jun, Katsuta, Junichiro, Kitaguchi, Takao, Kokubun, Motohide, Makishima, Kazuo, Mizuno, Tsunefumi, Mori, Kunishiro, Nakamori, Takeshi, Nakano, Toshio, Nakazawa, Kazuhiro, Noda, Hirofumi, Odaka, Hirokazu, Ohno, Masanori, Ohta, Masayuki, Saito, Shinya, Sato, Goro, Sato, Rie, Takeda, Shin'ichiro, Takahashi, Hiromitsu, Takahashi, Tadayuki, Tanaka, Takaaki, Tanaka, Yasuyuki, Terada, Yukikatsu, Uchiyama, Hideki, Uchiyama, Yasunobu, Yamaoka, Kazutaka, Yatsu, Yoichi, Yonetoku, Daisuke, Yuasa, Takayuki, Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), Stanford University, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Stanford University [Stanford], Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Shields, Field of view, x-rays, 01 natural sciences, 010309 optics, satellites, 0103 physical sciences, Gamma ray detectors, 010303 astronomy & astrophysics, Instrumentation, ComputingMilieux_MISCELLANEOUS, Remote sensing, detectors, Physics, [PHYS]Physics [physics], Spacecraft, business.industry, Mechanical Engineering, Detector, polarimeters, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Polarimeter, Polarization (waves), Electronic, Optical and Magnetic Materials, gamma rays, astronomy, Crab Nebula, Space and Planetary Science, Control and Systems Engineering, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

著者人数: 42名, Accepted: 2018-03-19, 資料番号: SA1170324000

Published
2018

17. Glimpse of the highly obscured HMXB IGR J16318−4848 with Hitomi

Author

Aharonian , Felix, Akamatsu , Hiroki, Akimoto , Fumie, Allen , StevenW., Angelini , Lorella, Audard , Marc, Awaki , Hisamitsu, Axelsson , Magnus, Bamba , Aya, Bautz , MarshallW., Blandford , Roger, Brenneman , LauraW., Brown , GregoryV., Bulbul , Esra, Cackett , EdwardM., Chernyakova , Maria, Chiao , MengP., Coppi , PaoloS., Costantini , Elisa, De Plaa , Jelle, de Vries , CorP., Den Herder , Jan-Willem, Done , Chris, Dotani , Tadayasu, Ebisawa , Ken, Eckart , MeganE., Enoto , Teruaki, Ezoe , Yuichiro, Fabian , AndrewC., Ferrigno , Carlo, Foster , AdamR., Fujimoto , Ryuichi, Fukazawa , Yasushi, Furuzawa , Akihiro, Galeazzi , Massimiliano, Gallo , LuigiC., Gandhi , Poshak, Giustini , Margherita, Goldwurm , Andrea, Gu , Liyi, Guainazzi , Matteo, Haba , Yoshito, Hagino , Kouichi, Hamaguchi , Kenji, Harrus , IlanaM., Hatsukade , Isamu, Hayashi , Katsuhiro, Hayashi , Takayuki, Hayashida , Kiyoshi, Hiraga , JunkoS., Hornschemeier , Ann, Hoshino , Akio, Hughes , JohnP., Ichinohe , Yuto, Iizuka , Ryo, Inoue , Hajime, Inoue , Yoshiyuki, Ishida , Manabu, Ishikawa , Kumi, Ishisaki , Yoshitaka, Iwai , Masachika, Kaastra , Jelle, Kallman , Tim, Kamae , Tsuneyoshi, Kataoka , Jun, Katsuda , Satoru, Kawai , Nobuyuki, Kelley , RichardL., Kilbourne , CarolineA., Kitaguchi , Takao, Kitamoto , Shunji, Kitayama , Tetsu, Kohmura , Takayoshi, Kokubun , Motohide, Koyama , Katsuji, Koyama , Shu, Kretschmar , Peter, Krimm , HansA., Kubota , Aya, Kunieda , Hideyo, Laurent , Philippe, Lee , Shiu-Hang, Leutenegger , MauriceA., Limousin , OlivierO., Loewenstein , Michael, Long , KnoxS., Lumb , David, Madejski , Greg, Maeda , Yoshitomo, Maier , Daniel, Makishima , Kazuo, Markevitch , Maxim, Matsumoto , Hironori, Matsushita , Kyoko, Mccammon , Dan, McNamara , BrianR., Mehdipour , Missagh, Miller , EricD., Miller , JonM., Mineshige , Shin, Mitsuda , Kazuhisa, Mitsuishi , Ikuyuki, Miyazawa , Takuya, Mizuno , Tsunefumi, Mori , Hideyuki, Mori , Koji, Mukai , Koji, Murakami , Hiroshi, Mushotzky , RichardF., Nakagawa , Takao, Nakajima , Hiroshi, Nakamori , Takeshi, Nakashima , Shinya, Nakazawa , Kazuhiro, Nobukawa , KumikoK., Nobukawa , Masayoshi, Noda , Hirofumi, Odaka , Hirokazu, Ohashi , Takaya, Ohno , Masanori, Okajima , Takashi, Ota , Naomi, Ozaki , Masanobu, Paerels , Frits, Paltani , Stéphane, Petre , Robert, Pinto , Ciro, Porter , FrederickS., Pottschmidt , Katja, Reynolds , ChristopherS., Safi-Harb , Samar, Saito , Shinya, Sakai , Kazuhiro, Sasaki , Toru, Sato , Goro, Sato , Kosuke, Sato , Rie, Sawada , Makoto, Schartel , Norbert, Serlemtsos , PeterJ., Seta , Hiromi, Shidatsu , Megumi, Simionescu , Aurora, Smith , RandallK., Soong , Yang, Stawarz , Łukasz, Sugawara , Yasuharu, Sugita , Satoshi, Szymkowiak , Andrew, Tajima , Hiroyasu, Takahashi , Hiromitsu, Takahashi , Tadayuki, Takeda , Shiníchiro, Takei , Yoh, Tamagawa , Toru, Tamura , Takayuki, Tanaka , Takaaki, Tanaka , Yasuo, Tanaka , YasuyukiT., Tashiro , MakotoS., Tawara , Yuzuru, Terada , Yukikatsu, Terashima , Yuichi, Tombesi , Francesco, Tomida , Hiroshi, Tsuboi , Yohko, Tsujimoto , Masahiro, Tsunemi , Hiroshi, Tsuru , Takeshi, Uchida , Hiroyuki, Uchiyama , Hideki, Uchiyama , Yasunobu, Ueda , Shutaro, Ueda , Yoshihiro, Uno , Shiníchiro, Urry , C.Megan, Ursino , Eugenio, Watanabe , Shin, Werner , Norbert, Wilkins , DanR., Williams , BrianJ., Yamada , Shinya, Yamaguchi , Hiroya, Yamaoka , Kazutaka, Yamasaki , NorikoY., Yamauchi , Makoto, Yamauchi , Shigeo, Yaqoob , Tahir, Yatsu , Yoichi, Yonetoku , Daisuke, Zhuravleva , Irina, Zoghbi , Abderahmen, Nakaniwa , Nozomi, AstroParticule et Cosmologie ( APC - UMR 7164 ), Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), and Hitomi

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

International audience; We report on a Hitomi observation of IGR J16318−4848, a high-mass X-ray binary system with an extremely strong absorption of N_H ∼ 10^24 cm^−2. Previous X-ray studies revealed that its spectrum is dominated by strong fluorescence lines of Fe as well as continuum emission lines. For physical and geometrical insight into the nature of the reprocessing material, we utilized the high spectroscopic resolving power of the X-ray microcalorimeter (the soft X-ray spectrometer: SXS) and the wide-band sensitivity by the soft and hard X-ray imagers (SXI and HXI) aboard Hitomi. Even though the photon counts are limited due to unintended off-axis pointing, the SXS spectrum resolves Fe Kα_1 and Kα_2 lines and puts strong constraints on the line centroid and line width. The line width corresponds to a velocity of 160$$^{+300}_{-70}$$ km s^−1. This represents the most accurate, and smallest, width measurement of this line made so far from the any X-ray binary, much less than the Doppler broadening and Doppler shift expected from speeds that are characteristic of similar systems. Combined with the K-shell edge energy measured by the SXI and HXI spectra, the ionization state of Fe is estimated to be in the range of Fe i–iv. Considering the estimated ionization parameter and the distance between the X-ray source and the absorber, the density and thickness of the materials are estimated. The extraordinarily strong absorption and the absence of a Compton shoulder component have been confirmed. These characteristics suggest reprocessing materials that are distributed in a narrow solid angle or scattering, primarily by warm free electrons or neutral hydrogen. This measurement was achieved using the SXS detection of 19 photons. It provides strong motivation for follow-up observations of this and other X-ray binaries using the X-ray Astrophysics Recovery Mission and other comparable future instruments.

Published
2018

18. Search for thermal X-ray features from the Crab nebula with Hitomi Soft X-ray Spectrometer

Author

Aharonian, Felix, Akamatsu, Hiroki, Akimoto, Fumie, Allen, Steven W., Angelini, Lorella, Audard, Marc, Awaki, Hisamitsu, Axelsson, Magnus, Bamba, Aya, Bautz, Marshall W., Blandford, Roger, Brenneman, Laura W., Brown, Greg V., Bulbul, Esra, Cackett, Edward M., Chernyakova, Maria, Chiao, Meng P., Coppi, Paolo S., Costantini, Elisa, de Plaa, Jelle, de Vries, Cor P., den Herder, Jan-Willem, Done, Chris, Dotani, Tadayasu, Ebisawa, Ken, Eckart, Megan E., Enoto, Teruaki, Ezoe, Yuichiro, Fabian, Andrew C., Ferrigno, Carlo, Foster, Adam R., Fujimoto, Ryuichi, Fukazawa, Yasushi, Furuzawa, Akihiro, Galeazzi, Massimiliano, Gallo, Luigi C., Gandhi, Poshak, Giustini, Margherita, Goldwurm, Andrea, Gu, Liyi, Guainazzi, Matteo, Haba, Yoshito, Hagino, Kouichi, Hamaguchi, Kenji, Harrus, Ilana M., Hatsukade, Isamu, Hayashi, Katsuhiro, Hayashi, Takayuki, Hayashida, Kiyoshi, Hiraga, Junko S., Hornschemeier, Ann, Hoshino, Akio, Hughes, John P., Ichinohe, Yuto, Iizuka, Ryo, Inoue, Hajime, Inoue, Yoshiyuki, Ishida, Manabu, Ishikawa, Kumi, Ishisaki, Yoshitaka, Kaastra, Jelle, Kallman, Tim, Kamae, Tsuneyoshi, Kataoka, Jun, Katsuda, Satoru, Kawai, Nobuyuki, Kelley, Richard L., Kilbourne, Caroline A., Kitaguchi, Takao, Kitamoto, Shunji, Kitayama, Tetsu, Kohmura, Takayoshi, Kokubun, Motohide, Koyama, Katsuji, Koyama, Shu, Kretschmar, Peter, Krimm, Hans A., Kubota, Aya, Kunieda, Hideyo, Laurent, Philippe, Lee, Shiu-Hang, Leutenegger, Maurice A., Limousin, Olivier O., Loewenstein, Michael, Long, Knox S., Lumb, David, Madejski, Greg, Maeda, Yoshitomo, Maier, Daniel, Makishima, Kazuo, Markevitch, Maxim, Matsumoto, Hironori, Matsushita, Kyoko, McCammon, Dan, McNamara, Brian R., Mehdipour, Missagh, Miller, Eric D., Miller, Jon M., Mineshige, Shin, Mitsuda, Kazuhisa, Mitsuishi, Ikuyuki, Miyazawa, Takuya, Mizuno, Tsunefumi, Mori, Hideyuki, Mori, Koji, Mukai, Koji, Murakami, Hiroshi, Mushotzky, Richard F., Nakagawa, Takao, Nakajima, Hiroshi, Nakamori, Takeshi, Nakashima, Shinya, Nakazawa, Kazuhiro, Nobukawa, Kumiko K., Nobukawa, Masayoshi, Noda, Hirofumi, Odaka, Hirokazu, Ohashi, Takaya, Ohno, Masanori, Okajima, Takashi, Ota, Naomi, Ozaki, Masanobu, Paerels, Frits, Paltani, Stephane, Petre, Robert, Pinto, Ciro, Porter, Frederick S., Pottschmidt, Katja, Reynolds, Christopher S., Safi-Harb, Samar, Saito, Shinya, Sakai, Kazuhiro, Sasaki, Toru, Sato, Goro, Sato, Kosuke, Sato, Rie, Sato, Toshiki, Sawada, Makoto, Schartel, Norbert, Serlemtsos, Peter J., Seta, Hiromi, Shidatsu, Megumi, Simionescu, Aurora, Smith, Randall K., Soong, Yang, Stawarz, Lukasz, Sugawara, Yasuharu, Sugita, Satoshi, Szymkowiak, Andrew, Tajima, Hiroyasu, Takahashi, Hiromitsu, Takahashi, Tadayuki, Takeda, Shinichiro, Takei, Yoh, Tamagawa, Toru, Tamura, Takayuki, Tanaka, Takaaki, Tanaka, Yasuo, Tanaka, Yasuyuki T., Tashiro, Makoto S., Tawara, Yuzuru, Terada, Yukikatsu, Terashima, Yuichi, Tombesi, Francesco, Tomida, Hiroshi, Tsuboi, Yohko, Tsujimoto, Masahiro, Tsunemi, Hiroshi, Tsuru, Takeshi Go, Uchida, Hiroyuki, Uchiyama, Hideki, Uchiyama, Yasunobu, Ueda, Shutaro, Ueda, Yoshihiro, Uno, Shinichiro, Urry, C. Megan, Ursino, Eugenio, Watanabe, Shin, Werner, Norbert, Wilkins, Dan R., Williams, Brian J., Yamada, Shinya, Yamaguchi, Hiroya, Yamaoka, Kazutaka, Yamasaki, Noriko Y., Yamauchi, Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yatsu, Yoichi, Yonetoku, Daisuke, Zhuravleva, Irina, Zoghbi, Abderahmen, Tominaga, Nozomu, and Moriya, Takashi J.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

The Crab nebula originated from a core-collapse supernova (SN) explosion observed in 1054 A.D. When viewed as a supernova remnant (SNR), it has an anomalously low observed ejecta mass and kinetic energy for an Fe-core collapse SN. Intensive searches were made for a massive shell that solves this discrepancy, but none has been detected. An alternative idea is that the SN1054 is an electron-capture (EC) explosion with a lower explosion energy by an order of magnitude than Fe-core collapse SNe. In the X-rays, imaging searches were performed for the plasma emission from the shell in the Crab outskirts to set a stringent upper limit to the X-ray emitting mass. However, the extreme brightness of the source hampers access to its vicinity. We thus employed spectroscopic technique using the X-ray micro-calorimeter onboard the Hitomi satellite. By exploiting its superb energy resolution, we set an upper limit for emission or absorption features from yet undetected thermal plasma in the 2-12 keV range. We also re-evaluated the existing Chandra and XMM-Newton data. By assembling these results, a new upper limit was obtained for the X-ray plasma mass of

Published
2017

19. $Hitomi$ constraints on the 3.5 keV line in the Perseus galaxy cluster

Author

Hitomi Collaboration, Aharonian, Felix A., Akamatsu, Hiroki, Akimoto, Fumie, Allen, Steven W., Angelini, Lorella, Arnaud, Keith A., Audard, Marc, Awaki, Hisamitsu, Axelsson, Magnus, Bamba, Aya, Bautz, Marshall W., Blandford, Roger D., Brenneman, Laura W., Brown, Gregory V., Bulbul, Esra, Cackett, Edward M., Chernyakova, Maria, Chiao, Meng P., Coppi, Paolo, Costantini, Elisa, de Plaa, Jelle, Herder, Jan-Willem den, Done, Chris, Dotani, Tadayasu, Ebisawa, Ken, Eckart, Megan E., Enoto, Teruaki, Ezoe, Yuichiro, Fabian, Andrew C., Ferrigno, Carlo, Foster, Adam R., Fujimoto, Ryuichi, Fukazawa, Yasushi, Furuzawa, Akihiro, Galeazzi, Massimiliano, Gallo, Luigi C., Gandhi, Poshak, Giustini, Margherita, Goldwurm, Andrea, Gu, Liyi, Guainazzi, Matteo, Haba, Yoshito, Hagino, Kouichi, Hamaguchi, Kenji, Harrus, Ilana, Hatsukade, Isamu, Hayashi, Katsuhiro, Hayashi, Takayuki, Hayashida, Kiyoshi, Hiraga, Junko, Hornschemeier, Ann E., Hoshino, Akio, Hughes, John P., Ichinohe, Yuto, Iizuka, Ryo, Inoue, Hajime, Inoue, Shota, Inoue, Yoshiyuki, Ishibashi, Kazunori, Ishida, Manabu, Ishikawa, Kumi, Ishisaki, Yoshitaka, Itoh, Masayuki, Iwai, Masachika, Iyomoto, Naoko, Kaastra, Jelle S., Kallman, Timothy, Kamae, Tuneyoshi, Kara, Erin, Kataoka, Jun, Katsuda, Satoru, Katsuta, Junichiro, Kawaharada, Madoka, Kawai, Nobuyuki, Kelley, Richard L., Khangulyan, Dmitry, Kilbourne, Caroline A., King, Ashley L., Kitaguchi, Takao, Kitamoto, Shunji, Kitayama, Tetsu, Kohmura, Takayoshi, Kokubun, Motohide, Koyama, Shu, Koyama, Katsuji, Kretschmar, Peter, Krimm, Hans A., Kubota, Aya, Kunieda, Hideyo, Laurent, Philippe, Lebrun, Francois, Lee, Shiu-Hang, Leutenegger, Maurice, Limousin, Olivier, Loewenstein, Michael, Long, Knox S., Lumb, David, Madejski, Grzegorz M., Maeda, Yoshitomo, Maier, Daniel, Makishima, Kazuo, Markevitch, Maxim, Matsumoto, Hironori, Matsushita, Kyoko, McCammon, Dan, McNamara, Brian R., Mehdipour, Missagh, Miller, Eric D., Miller, Jon M., Mineshige, Shin, Mitsuda, Kazuhisa, Mitsuishi, Ikuyuki, Miyazawa, Takuya, Mizuno, Tsunefumi, Mori, Hideyuki, Mori, Koji, Moseley, Harvey, Mukai, Koji, Murakami, Hiroshi, Murakami, Toshio, Mushotzky, Richard F., Nakagawa, Takao, Nakajima, Hiroshi, Nakamori, Takeshi, Nakano, Toshio, Nakashima, Shinya, Nakazawa, Kazuhiro, Nobukawa, Kumiko, Nobukawa, Masayoshi, Noda, Hirofumi, Nomachi, Masaharu, O'Dell, Steve L., Odaka, Hirokazu, Ohashi, Takaya, Ohno, Masanori, Okajima, Takashi, Ota, Naomi, Ozaki, Masanobu, Paerels, Frits, Paltani, Stephane, Parmar, Arvind, Petre, Robert, Pinto, Ciro, Pohl, Martin, Porter, F. Scott, Pottschmidt, Katja, Ramsey, Brian D., Reynolds, Christopher S., Russell, Helen R., Safi-Harb, Samar, Saito, Shinya, Sakai, Kazuhiro, Sameshima, Hiroaki, Sasaki, Toru, Sato, Goro, Sato, Kosuke, Sato, Rie, Sawada, Makoto, Schartel, Norbert, Serlemitsos, Peter J., Seta, Hiromi, Shidatsu, Megumi, Simionescu, Aurora, Smith, Randall K., Soong, Yang, Stawarz, Lukasz, Sugawara, Yasuharu, Sugita, Satoshi, Szymkowiak, Andrew E., Tajima, Hiroyasu, Takahashi, Hiromitsu, Takahashi, Tadayuki, Takeda, Shin'ichiro, Takei, Yoh, Tamagawa, Toru, Tamura, Keisuke, Tamura, Takayuki, Tanaka, Takaaki, Tanaka, Yasuo, Tanaka, Yasuyuki, Tashiro, Makoto, Tawara, Yuzuru, Terada, Yukikatsu, Terashima, Yuichi, Tombesi, Francesco, Tomida, Hiroshi, Tsuboi, Yohko, Tsujimoto, Masahiro, Tsunemi, Hiroshi, Tsuru, Takeshi, Uchida, Hiroyuki, Uchiyama, Hideki, Uchiyama, Yasunobu, Ueda, Shutaro, Ueda, Yoshihiro, Ueno, Shiro, Uno, Shin'ichiro, Urry, C. Meg, Ursino, Eugenio, de Vries, Cor P., Watanabe, Shin, Werner, Norbert, Wik, Daniel R., Wilkins, Dan R., Williams, Brian J., Yamada, Shinya, Yamaguchi, Hiroya, Yamaoka, Kazutaka, Yamasaki, Noriko Y., Yamauchi, Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yatsu, Yoichi, Yonetoku, Daisuke, Yoshida, Atsumasa, Zhuravleva, Irina, Zoghbi, Abderahmen, Laboratoire AIM, Université Paris Diderot - Paris 7 ( UPD7 ) -Centre d'Etudes de Saclay, Hitomi, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
galaxies: clusters: individual, Cosmology and Nongalactic Astrophysics (astro-ph.CO), galaxies: clusters: intracluster medium, clusters: individual: A426 [galaxies], Astrophysics::High Energy Astrophysical Phenomena, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], Dark matter, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, galaxies: clusters: individual (A426), 01 natural sciences, dark matter, X-ray, Settore FIS/05 - Astronomia e Astrofisica, gas, 0103 physical sciences, calorimeter, Emission spectrum, Spectroscopy, 010303 astronomy & astrophysics, Galaxy cluster, Astrophysics::Galaxy Astrophysics, Line (formation), High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Nebula, 010308 nuclear & particles physics, dark matter: decay, Astronomy and Astrophysics, charge exchange, Astrophysics - Astrophysics of Galaxies, K-line, Galaxy, flux, Space and Planetary Science, clusters: intracluster medium [galaxies], Astrophysics of Galaxies (astro-ph.GA), X-rays: galaxies: clusters, galaxy: cluster, galaxies: clusters [X-rays], Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], signature, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

High-resolution X-ray spectroscopy with Hitomi was expected to resolve the origin of the faint unidentified E=3.5 keV emission line reported in several low-resolution studies of various massive systems, such as galaxies and clusters, including the Perseus cluster. We have analyzed the Hitomi first-light observation of the Perseus cluster. The emission line expected for Perseus based on the XMM-Newton signal from the large cluster sample under the dark matter decay scenario is too faint to be detectable in the Hitomi data. However, the previously reported 3.5 keV flux from Perseus was anomalously high compared to the sample-based prediction. We find no unidentified line at the reported high flux level. Taking into account the XMM measurement uncertainties for this region, the inconsistency with Hitomi is at a 99% significance for a broad dark-matter line and at 99.7% for a narrow line from the gas. We do not find anomalously high fluxes of the nearby faint K line or the Ar satellite line that were proposed as explanations for the earlier 3.5 keV detections. We do find a hint of a broad excess near the energies of high-n transitions of Sxvi (E=3.44 keV rest-frame) -- a possible signature of charge exchange in the molecular nebula and another proposed explanation for the unidentified line. While its energy is consistent with XMM pn detections, it is unlikely to explain the MOS signal. A confirmation of this interesting feature has to wait for a more sensitive observation with a future calorimeter experiment., Discussion of systematics significantly expanded. 9 pages, 5 figures; ApJ Lett. in press

Published
2017

20. Discovery of strong radiative recombination continua from IC443

Author

Yamaguchi, Hiroya, Ozawa, Midori, Koyama, Katsuji, Hiraga, Junko S., Ozaki, Masanobu, and Yonetoku, Daisuke

Subjects
ISM: supernova remnants - radiation mechanisms: thermal
Abstract

The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, We present the Suzaku detection of strong free-bound emission from the Galactic middle-aged supernova remnant (SNR) IC 443. A previous ASCA observation revealed that the Lyalfpha fluxes of Si and S are significantly higher than those expected from the electron temperature of the bremsstrahlung continuum (Kawasaki et al. 2002). Therefore, it was claimed that the thermal plasma in this SNR is in "overionization". In the XIS spectrum of IC 443, we discovered hump-like features around at 2.7 and 3.5 keV as well as the strong Lyalpha lines. These humps are well represented by radiative recombination continua (RRC) of H-like Si and S with the electron temperature of approximately 0.6 keV. The ionization temperatures of Si and S determined from the intensity ratios of the RRC to He-like Kalpha line are approximately 1.0 keV and approximately 1.2 keV, respectively. We thus find firm evidence for an extremely-overionized (recombining) plasma. As the origin of the overionization, a thermal conduction scenario argued in the previous work is not favored in our new results. We propose that the highly-ionized gas were made at the initial phase of the SNR evolution in dense regions around a massive progenitor, and the low electron temperature is due to a rapid cooling by an adiabatic expansion., Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science, 資料番号: AA0064574024, レポート番号: JAXA-SP-09-008E

Published
2010

21. Suzaku Observations of SGR 1900+14 and SGR 1806-20

Author

Nakagawa, Yujin E., Mihara, Tatehiro, Yoshida, Atsumasa, Yamaoka, Kazutaka, Sugita, Satoshi, Murakami, Toshio, Yonetoku, Daisuke, Suzuki, Motoko, Nakajima, Motoki, and Nakazawa, Kazuhiro

Subjects
stars: pulsars: individual (sgr 1900+14,sgr 1806-20), stars: neutron, xmm-newton, magnetized neutron-stars, ray bursts, board suzaku, short bursts, soft gamma-repeaters, giant flare, distance, x-rays: individual (sgr 1900+14,sgr 1806-20), sgr-1806-20, discovery
Abstract

Spectral and timing studies of Suzaku ToO observations of two SGRs, 1900+14 and 1806-20, are presented. The X-ray quiescent emission spectra were well fitted by a two blackbody function, or a blackbody plus a power-law model. The non-thermal hard component discovered by INTEGRAL was detected by PIN diodes and its spectrum was reproduced by the power-law model reported by INTEGRAL. The XIS detected a periodicity of P = 5.1998 +/- 0.0002s for SGR 1900+14 and P = 7.6022 +/- 0.0007s for SGR 1806-20. The pulsed fraction was related to the burst activity for SGR 1900+14.

Published
2009

22. In-orbit timing calibration of the hard X-ray detector on board Suzaku

Author

Enoto, Teruaki, Miyawaki, Ryouhei, Ishisaki, Yoshitaka, Dotani, Tadayasu, Ebisawa, Ken, Ozaki, Masanobu, Ueda, Yoshihiro, Kuiper, Lucien, Endo, Manabu, Fukazawa, Yasushi, Kamae, Tsuneyoshi, Kawaharada, Madoka, Kokubun, Motohide, Kuroda, Yoshikatsu, Makishinia, Kazuo, Masukawa, Kazunori, Mizuno, Tsunefumi, Murakami, Toshio, Nakazawa, Kazuhiro, Nakajima, Atsushi, Nomach, Masaharu, Shibayama, Naoki, Takahash, Tadayuki, Takahashi, Hiromitsu, Tamagawa, Toru, Watanabe, Shin, Yamaguchi, Makio, Yamaoka, Kazutaka, and Yonetoku, Daisuke

Subjects
space vehicles : instruments, time, X-rays : general
Abstract

The hard X-ray detector (HXD) aboard the X-ray satellite Suzaku is designed to have a good timing capability with a 61 its time resolution. In addition to detailed descriptions of the HXD timing system, results of in-orbit timing calibration and the performance of the HXD are summarized. The relative accuracy of time measurements of the HXD event was confirmed to have an accuracy of 1.9 x 10(-9) s s(-1) per day, and the absolute timing was confirmed to be accurate to 360 mu s or better. The results were achieved mainly through observations of the Crab pulsar, including simultaneous ones with RXTE, INTEGRAL, and Swift.

Published
2008

23. マルチプラットフォームを想定したガンマ線バースト偏光度検出器の開発

Author

Wilson-Hodge, Colleen, Daigle, Stephen, Gunji, Shuichi, Nakamori, Takeshi, Katagiri, Jun, Kishikawa, Tatsuya, Oikawa, Yuma, Ueda, Tatsuya, Takakura, Mika, Ramsey, Brian, Gaskin, Jessica, Yonetoku, Daisuke, Mihara, Tatehiro, Hayashida, Kiyoshi, Kishimoto, Yuji, Saito, Yoshitaka, Takahashi, Hiromitsu, Mizuno, Tsunefumi, Yatsu, Yoichi, and Toma, Kenji

Abstract

第15回宇宙科学シンポジウム (2015年1月6日-7日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県, 15th Space Science Symposium (January 6-7, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 著者人数: 20名, 資料番号: SA6000034042, レポート番号: P-042

Published
2015

25. Improvements of the Astro-E2 Hard X-ray Detector (HXD-II)

Author

Madejski, G. M., Niko, H., Okada, Y., Tominaga, S., Kokubun, Motohide, Abe, Keiichi, Ezoe, Yuichiro, Fukazawa, Yasushi, Hong, Soojing, Inoue, Hokuto, Itoh, Takeshi, Kamae, Tsuneyoshi, Kasama, Daisuke, Kawaharada, Madoka, Kawano, Naomi, Kawashima, K., Kawasoe, Satoshi, Kobayashi, Yoshihito, Kotoku, Junichi, Kouda, Manabu, Kubota, Aya, Makishima, Kazuo, Mitani, Takefumi, Miyasaka, Hiromasa, Miyawaki, Ryohei, Mori, Kunishiro, Mori, Masanori, Murakami, Toshio, Murashima, Mio M., Nakazawa, Kazuhiro, Nomachi, Masaharu, Ohno, Masanori, Oonuki, Kosuke, Sato, Goro, Suzuki, Masaya, Takahashi, Hiromitsu, Takahashi, Isao, Takahashi, Tadayuki, Tamura, Kenichi, Tanaka, Takaaki, Tashiro, Makoto, Terada, Yukikatsu, Watanabe, Shin, Yamaoka, Kazutaka, Yanagida, Takayuki, and Yonetoku, Daisuke

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Range (particle radiation), Nuclear Energy and Engineering, Proton, Nuclear electronics, Detector, Resolution (electron density), X-ray detector, Irradiation, Electrical and Electronic Engineering, Sensitivity (electronics)
Abstract

著者人数: 46名, 資料番号: SA1003790000

Published
2004

26. High-z gamma-ray bursts for unraveling the dark ages mission HiZ-GUNDAM

Author

Yonetoku, Daisuke, Mihara, Tatehiro, Sawano, Tatsuya, Ikeda, Hirokazu, Harayama, Atsushi, Takata, Shunsuke, Yoshida, Kazuki, Seta, Hiroki, Toyanago, Asuka, Kagawa, Yasuaki, Kawai, Kentaro, Kawai, Nobuyuki, Sakamoto, Takanori, Serino, Motoko, Kurosawa, Shunsuke, Gunji, Shuichi, Tanimori, Toru, Murakami, Toshio, Yatsu, Yoichi, Yamaoka, Kazutaka, Yoshida, Atsumasa, Kawabata, Koji, Matsumoto, Toshio, Tsumura, Koji, Matsuura, Shuji, Shirahata, Mai, Okita, Hirofumi, Yanagisawa, Kensi, Yoshida, Michitoshi, Motohara, Kentaro, and group, HiZ-GUNDAM working

Subjects
Physics, Astronomical Objects, Cosmology and Nongalactic Astrophysics (astro-ph.CO), media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Universe, Redshift, Cosmology, law.invention, Telescope, law, Physics::Space Physics, Dark Ages, Satellite, Astrophysics::Earth and Planetary Astrophysics, Gamma-ray burst, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), media_common, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We are now investigating and studying a small satellite mission HiZ-GUNDAM for future observation of gamma-ray bursts (GRBs). The mission concept is to probe "the end of dark ages and the dawn of formation of astronomical objects", i.e. the physical condition of early universe beyond the redshift z > 7. We will consider two kinds of mission payloads, (1) wide field X-ray imaging detectors for GRB discovery, and (2) a near infrared telescope with 30 cm in diameter to select the high-z GRB candidates effectively. In this paper, we explain some requirements to promote the GRB cosmology based on the past observations, and also introduce the mission concept of HiZ-GUNDAM and basic development of X-ray imaging detectors., 12 pages, 9 figures, SPIE Astronomical Telescopes + Instrumentation (2014)

Published
2014

27. The dark energy measurement in the early universe with Gamma-Ray Bursts

Author

Yonetoku, Daisuke, Murakami, Toshio, Tsutsui, Ryo, Nakamura, Takashi, and Takahashi, Keitaro

Subjects
Gamma-Ray: Bursts - Cosmology: Dark Energy - Distance Ladder
Abstract

The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, We calibrated the peak energy-peak luminosity relation of GRBs (so called E(sub p) - L(sup p) ; Yonetoku relation) using 52 events with the redshift z < 1.755 without assuming any cosmological models. The luminosity distances to GRBs are estimated from those of large amount of Type Ia supernovae with z < 1.755. This calibrated E(sub p) - L(sup p) relation can be used as a new cosmic distance ladder toward higher redshifts. We determined the luminosity distances of 36 GRBs in 1.8 < z < 8.3 using the calibrated relation and plotted the likelihood contour in (omega(sub m), omega(sub lamda) plane. We obtained (Omega(sub m), Omega(sub lamda) = (0.37(sup +0.14)(sub -0.11), 0.63(sup +0.11)(sub -0.14) for a flat universe. We can say that our universe in 1.8 < z < 8.3 is compatible with the cosmological model derived for z 1< 1.8. This suggests that the time variation of the dark energy may be small or zero up to z approximately 8., Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science, 資料番号: AA0064574139, レポート番号: JAXA-SP-09-008E

Published
2010

28. Preflight Performance of the Astro-E Hard X-ray Detector

Author

Onishi, T., Tanaka, M., Tanihata, Chiharu, Kataoka, Jun, Murakami, Toshio, Ota, Naomi, Ozawa, Hideki, Takahashi, Tadayuki, Tamura, Takayuki, Uchiyama, Yasunobu, Watanabe, Shin, Yamaoka, Kazutaka, Yonetoku, Daisuke, Ezoe, Yuichiro, Fukazawa, Yasushi, Isobe, N., Iyomoto, Naoko, Kamae, Tsuneyoshi, Kokubun, Motohide, Kotoku, J., Kubota, Aya, Makishima, K., Matsumoto, Y., Mizuno, T., Nakazawa, Kazuhiro, Sugiho, M., Takahashi, I., Tashiro, M., Terada, Y., and Nomachi, M.

Abstract

著者人数: 39名, Note: to appear in SPIE 3765, 1999, 資料番号: SA8000204000

Published
1999

29. Strict Limit on CPT Violation from Polarization of Gamma-Ray Bursts

Author

Toma, Kenji, Mukohyama, Shinji, Yonetoku, Daisuke, Murakami, Toshio, Gunji, Shuichi, Mihara, Tatehiro, Morihara, Yoshiyuki, Sakashita, Tomonori, Takahashi, Takuya, Wakashima, Yudai, Yonemochi, Hajime, and Toukairin, Noriyuki

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), High Energy Physics - Theory, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), High Energy Physics - Theory (hep-th), Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Phenomenology, FOS: Physical sciences, High Energy Physics::Experiment, General Relativity and Quantum Cosmology (gr-qc), Astrophysics - High Energy Astrophysical Phenomena, General Relativity and Quantum Cosmology
Abstract

We report the strictest observational verification of CPT invariance in the photon sector, as a result of gamma-ray polarization measurement of distant gamma-ray bursts (GRBs), which are brightest stellar-size explosions in the universe. We detected the gamma-ray polarization of three GRBs with high significance, and the source distances may be constrained by a well-known luminosity indicator for GRBs. For the Lorentz- and CPT-violating dispersion relation E_{\pm}^2=p^2 \pm 2\xi p^3/M_{Pl}, where \pm denotes different circular polarization states of the photon, the parameter \xi is constrained as |\xi, Comment: 4 pages; accepted for publication in Physical Review Letters; redshift estimates of GRBs changed (i.e z=0.382 was wrong for GRB 110721A) and calculations of \xi limit improved from the previous version

Published
2012

30. Intrisic Dispersion of Correlations among Ep, Lp, and Eiso of Gamma Ray Bursts depends on the quality of Data Set

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, Murakami, Toshio, and Takahashi, Keitaro

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics - High Energy Astrophysical Phenomena
Abstract

We reconsider correlations among the spectral peak energy ($E_p$), 1-second peak luminosity ($L_p$) and isotropic energy (\Eiso), using the database constructed by \citet{yonetoku10} which consists of 109 Gamma-Ray Bursts (GRBs) whose redshifts are known and $E_p$, $L_p$ and \Eiso are well determined. We divide the events into two groups by their data quality. One (gold data set) consists of GRBs with peak energies determined by the Band model with four free parameters. On the other hand, GRBs in the other group (bronze data set) have relatively poor energy spectra so that their peak energies were determined by the Band model with fixed spectral index (i.e. three free parameters) or by the Cut-off power law (CPL) model with three free parameters. Using only the gold data set we found the intrinsic dispersion in $\log L_p$ ($=\sigma_{\rm int}$) is 0.13 and 0.22 for \tsutsui correlation ($T_L \equiv E_{\rm iso}/L_p$) and \yonetoku correlation, respectively. We also find that GRBs in the bronze data set have systematically larger $E_p$ than expected by the correlations constructed with the gold data set. This means that the intrinsic dispersion of correlations among $E_p$, $L_p$, and \Eiso of GRBs depends on the quality of data set. At present, using \tsutsui correlation with gold data set, we would be able to determine the luminosity distance with $\sim 16%$ error, which might be useful to determine the nature of the dark energy at high redshift $z > 3$., Comment: 11 pages, 1 figure, submitted to ApJ Letter

Published
2010

31. X-Ray Spectral Variability of the Seyfert Galaxy NGC 4051 Observed with Suzaku

Author

Gallo, Luigi C., Markowitz, Alex G., Reeves, James N., Fabian, Andrew C., Griffiths, Richard E., Miniutti, Giovanni, Terashima, Yuichi, Inoue, Hirohiko, Anabuki, Naohisa, Hayashida, Kiyoshi, Itoh, Takeshi, Kokubun, Motohide, Kubota, Aya, Takahashi, Tadayuki, Yamauchi, Makoto, Yonetoku, Daisuke, APC - Astrophysique des Hautes Energies (APC - AHE), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Lantz, Simone, Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)

Subjects
[SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Gaussian, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, FOS: Physical sciences, Astrophysics, 01 natural sciences, Spectral line, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], symbols.namesake, Ionization, 0103 physical sciences, Black-body radiation, Emission spectrum, 010303 astronomy & astrophysics, Physics, [SDU.ASTR.CO] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 010308 nuclear & particles physics, Astrophysics (astro-ph), Astronomy and Astrophysics, Galaxy, X-rays: galaxies, Amplitude, Space and Planetary Science, [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], galaxies: individual (NGC 4051), symbols, Equivalent width
Abstract

We report results from a Suzaku observation of the narrow-line Seyfert 1 NGC 4051. During our observation, large amplitude rapid variability is seen and the averaged 2--10 keV flux is 8.1x10^-12 erg s^-1 cm^-2, which is several times lower than the historical average. The X-ray spectrum hardens when the source flux becomes lower, confirming the trend of spectral variability known for many Seyfert 1 galaxies. The broad-band averaged spectrum and spectra in high and low flux intervals are analyzed. The spectra are first fitted with a model consisting of a power-law component, a reflection continuum originating in cold matter, a blackbody component, two zones of ionized absorber, and several Gaussian emission lines. The amount of reflection is rather large (R ~ 7, where R=1 corresponds to reflection by an infinite slab), while the equivalent width of the Fe-K line at 6.4 keV is modest (140 eV) for the averaged spectrum. We then model the overall spectra by introducing partial covering for the power-law component and reflection continuum independently. The column density for the former is 1x10^23 cm^-2, while it is fixed at 1x10^24 cm-2 for the latter. By comparing the spectra in different flux states, we identify the causes of spectral variability. (abridged), 19 pages, 18 figures, accepted for publication in PASJ (Suzaku 3rd special issue)

Published
2008

32. Gamma-Ray Bursts in $1.8 < z < 5.6$ Suggest that the Time Variation of the Dark Energy is Small

Author

Kodama, Yoshiki, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, Tsutsui, Ryo, and Nakamura, Takashi

Subjects
High Energy Physics - Phenomenology, Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Experiment, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics, General Relativity and Quantum Cosmology
Abstract

We calibrated the peak energy-peak luminosity relation of GRBs (so called Yonetoku relation) using 33 events with the redshift $z < 1.62$ without assuming any cosmological models. The luminosity distances to GRBs are estimated from those of large amount of Type Ia supernovae with $z, Comment: 4 pages, 4 figures, accepted to MNRAS

Published
2008

33. A possible observational evidence for $\theta^{-2}$ angular distribution of opening half-angle of GRB jets

Author

Yonetoku, Daisuke, Yamazaki, Ryo, Nakamura, Takashi, and Murakami, Toshio

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics
Abstract

We propose a method to estimate the pseudo jet opening half-angle of GRBs using the spectral peak energy ($\Ep$)--peak luminosity relation (so called Yonetoku relation) as well as the $\Ep$--collimation-corrected $\gamma$-ray energy relation (so called Ghirlanda relation). For bursts with known jet break times and redshifts, we compared the pseudo jet opening half-angle with the standard one and found that the differences are within a factor 2. We apply the method to 689 long GRBS. We found that the distribution function of the pseudo jet opening half-angle obeys $f(\theta_j)\propto\theta_j^{-2.2 \pm 0.2}$ with possible cutoffs for $\theta_j < 0.04$ and $\theta_j > 0.3$ although the log-normal fit is also possible. $\theta^{-2}$ distribution is compatible with the structured jet model. From the distribution function we found that the beaming correction for the rate of GRBs is $\sim 340$, which means $\sim 10^{-5}$ yr$^{-1}$ galaxy$^{-1}$ or only one in $10^2$ type Ib/c supernovae. We also found the evolution of the distribution function as a function of the redshift., Comment: 5 pages, 5 figures, submitted to MNRAS

Published
2005

35. Observing Gamma-Ray Bursts with ASTRO-H.

Author

Kawai, Nobuyuki and Yonetoku, Daisuke

Subjects
*GAMMA ray bursts, *CALORIMETERS, *ASTRONOMICAL observations, *AFTERGLOW (Physics), *REDSHIFT, *ABSORPTION spectra, *METAPHYSICAL cosmology
Abstract

The next Japanese X-ray Astronomy mission ASTRO-H, scheduled to be launched in 2014, will conduct the first observations with X-ray micro-calorimeter. Although it is not designed for fast follow-up, there would be chance for ToO observations of GRB afterglow to obtain a high resolution spectra that can be used to measure the absorption column density and the redshift of the GRB using absorption edges of heavy elements. We discuss the capability and scientific prospects for GRB observations with ASTRO-H. [ABSTRACT FROM AUTHOR]

Published
2010
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36. The Spectral Epeak-Luminosity and the Epeak-Eiso Relation: the Origin of Dispersion and Its Improvement.

Author

Yonetoku, Daisuke, Murakami, Toshio, Tsutsui, Ryo, Nakamura, Takashi, Takahashi, Keitaro, and Morihara, Yoshiyuki

Subjects
*DISPERSION (Chemistry), *GAMMA ray bursts, *STELLAR luminosity function, *METAPHYSICAL cosmology, *ASTRONOMICAL observations, *DARK matter, *DARK energy
Abstract

We formed a GRB cosmology project in Japan, and promote the observational cosmology with Gamma-ray bursts (GRBs). In this paper, we introduce recent result of our project with the spectral Epeak-Luminosity relations. We show the Hubble diagram up to the redshift of z = 8.2, and the confidence contour of the dark energy (ΩΛ) and the dark matter (Ωm) beyond z>2 beyond the current range measured by the Type Ia supernovae. After that, we investigate the origin of data dispersion of the Epeak-brightness relations, and suggest a possible improvement of their accuracy. [ABSTRACT FROM AUTHOR]

Published
2010
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37. Suzaku and Swift observations for X-ray afterglows; Investigation into the electron acceleration in the internal/external shocks.

Author

Yonetoku, Daisuke, Tanabe, Sachiko, Murakami, Toshio, Emura, N., Aoyama, Y., Kidamura, T., Kodaira, H., Kodama, Y., Kozaka, R., Nashimoto, T., Okuno, S., Yokota, S., Yoshinari, S., Abe, K., Onda, K., Tashiro, M. S., Urata, Y., Nakagawa, Y. E., Sugita, S., and Yamaoka, K.

Subjects
*AFTERGLOW (Physics), *X-ray astronomy, *X-ray spectroscopy, *GAMMA ray bursts, *ARTIFICIAL satellites
Abstract

We have performed ToO observations for three bright GRBs with the Japanese X-ray satellite “Suzaku”. Suzaku strongly supports the follow-up observations by Swift, especially in the late time afterglow phase, with its capabilities of larger effective area and wider energy band compared with Swift/XRT. In this presentation, mainly focusing on the X-ray afterglow of GRB 060904A, we introduce these ToO observation results. In GRB 060904A, we found rapid spectral softening with the photon indices from 1.5 to 5.3 during the steep decay (prompt tail) phase in the BAT and XRT data. This ultra soft spectra suddenly disappeared at the transition time from the prompt tail phase to the shallow decay one. After that, typical afterglow spectra with the photon indices of 2.0 are continuously and preciously monitored by both XRT and Suzaku/XIS up to 1 day since the burst trigger time. To explain this ultra soft spectra, we introduce a spectral cutoff model instead of power-law, and investigate the possibility of the maximum energy of electron distribution. We could successfully trace the temporal history of cutoff energy and it shows the time dependence of ∝t-3∼t-4 while the following afterglow spectra are quite stable. This fact indicates that the emitting material of prompt tail is due to completely different dynamics from the shallow decay component. Therefore we conclude the emission sites of two distinct phenomena obviously differ from each other. [ABSTRACT FROM AUTHOR]

Published
2008
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38. Redshift Dependent Lag-Luminosity Relation in 565 BASTE Gamma Ray Bursts.

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, and Kodama, Yoshiki

Subjects
REDSHIFT, GAMMA ray bursts, GAMMA ray astronomy, GAMMA rays, SPECTRUM analysis
Abstract

We compared redshifts zY measured from Yonetoku relation and zlag from the lag-luminosity relation for 565 BASTE GRBs and were surprised to find that the correlation between these two redshifts is very low. Assuming that the luminosity is a function of both zY and the intrinsic spectral lag τlag, we found a new redshift dependent lag-luminosity relation as L = 7.5×1050 erg/s(1+z)2.53τlag-0.282 with the correlation coefficient of 0.77. [ABSTRACT FROM AUTHOR]

Published
2008
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41. Hard x-ray imager for the NeXT mission.

Author

Nakazawa, Kazuhiro, Fukazawa, Yasushi, Kamae, Tuneyoshi, Kataoka, Jun, Kokubun, Motohide, Makishima, Kazuo, Mizuno, Tsunefumi, Murakami, Toshio, Nomachi, Masaharu, Tajima, Hiroyasu, Takahashi, Tadayuki, Tashiro, Makoto, Tamagawa, Toru, Terada, Yukikatsu, Watanabe, Shin, Yamaoka, Kazutaka, and Yonetoku, Daisuke

Published
2006
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42. GRB 980425 in the Off-Axis Jet Model of the Standard GRBs.

Author

Yamazaki, Ryo, Yonetoku, Daisuke, and Nakamura, Takashi

Subjects
*GAMMA ray bursts, *SPECTRUM analysis, *X-rays, *ELECTROMAGNETIC waves, *PHYSICAL sciences
Abstract

Using a simple off-axis jet model of GRBs, we can reproduce the observed unusual properties of the prompt emission of GRB 980425, such as the extremely low isotropic equivalent γ-ray energy, the low peak energy, the high fluence ratio, and the long spectral lag when the jet with the standard energy of ∼ 1051 ergs and the opening half-angle of 10°≤Δθ≤30° is seen from the off-axis viewing angle θv ∼ Δθ + 10γ-1, where γ is a Lorentz factor of the jet. For our adopted fiducial parameters, if the jet that caused GRB 980425 is viewed from the on-axis direction, the intrinsic peak energy Ep(1 + z) is ∼2.0–4.0 MeV, which corresponds to those of GRB 990123 and GRB 021004. Our model might be able to explain the other unusual properties of this event. We also discuss the connection of GRB 980425 in our model with the X-ray flash, and the origin of a class of GRBs with small Eγ such as GRB 030329. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2004
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43. Possible existence of the Ep-Lp and Ep-Eiso correlations for short gamma-ray bursts with a factor 5–100 dimmer than those for long gamma-ray bursts.

Author

Tsutsui, Ryo, Yonetoku, Daisuke, Nakamura, Takashi, Takahashi, Keitaro, and Morihara, Yoshiyuki

Subjects
*GAMMA ray bursts, *EXISTENCE theorems, *RADIATION, *STATISTICAL correlation, *REDSHIFT
Abstract

We analysed correlations among the rest-frame spectral peak energy Ep, the observed frame 64 ms peak isotropic luminosity Lp and the isotropic energy Eiso for 13 short gamma-ray burst (SGRB) candidates having the measured redshift z, Tobs90/(1 + z) < 2 s and well-determined spectral parameters. An SGRB candidate is regarded as a misguided SGRB if it is located in the 3σint dispersion region from the best-fitting function of the Ep-Eiso correlation for long GRBs (LGRBs), while the others are regarded as secure SGRBs possibly from compact star mergers. Using 8 secure SGRBs out of 13 SGRB candidates, we tested whether the Ep-Eiso and Ep-Lp correlations exist for SGRBs. We found that the Ep-Eiso correlation for SGRBs (Eiso = 1051.42 ± 0.15 erg s−1(Ep/774.5 keV)1.58 ± 0.28) seems to exist with the correlation coefficient r = 0.91 and chance probability p = 1.5 × 10−3. We also found that the Ep-Lp correlation for SGRBs (Lp = 1052.29 ± 0.066 erg s−1(Ep/774.5 keV)1.59 ± 0.11) is tighter than the Ep-Eiso correlation since r = 0.98 and p = 1.5 × 10−5. Both correlations for SGRBs are dimmer than those of LGRBs for the same Ep by factors ∼100 (Ep − Eiso) and ∼ 5(Ep − Lp). Applying the tighter Ep-Lp correlation for SGRBs to 71 bright Burst and Transient Source Experiment SGRBs, we found that pseudo-redshift z ranges from 0.097 to 2.258 with the mean 〈z〉 of 1.05. The redshifts of SGRBs apparently cluster at lower redshift than those of LGRBs (〈z 〉 ∼2.2), which supports the merger scenario of SGRBs. [ABSTRACT FROM AUTHOR]

Published
2013
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45. Constraints on w0 and w a of dark energy from high-redshift gamma-ray bursts.

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, Kodama, Yoshiki, and Takahashi, Keitaro

Subjects
DARK energy, GAMMA ray bursts, REDSHIFT, GAMMA ray sources, GAMMA rays, GAMMA ray astronomy
Abstract

We extend the Hubble diagram up to using 63 gamma-ray bursts (GRBs) via peak energy–peak luminosity relation (so-called Yonetoku relation), and obtain constraints on cosmological parameters including dynamical dark energy parametrized by . It is found that the current GRB data are consistent with the concordance model within 2σ level. Although constraints from GRBs themselves are not so strong, they can improve the conventional constraints from type Ia supernovae because GRBs have much higher redshifts. Further, we estimate the constraints on the dark energy parameters expected by future observations with Gamma-ray Large Area Space Telescope and Swift by Monte Carlo simulation. Constraints would improve substantially with another 150 GRBs. [ABSTRACT FROM AUTHOR]

Published
2009
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46. Gamma-ray bursts in 1.8 < z < 5.6 suggest that the time variation of the dark energy is small.

Author

Kodama, Yoshiki, Yonetoku, Daisuke, Murakami, Toshio, Tanabe, Sachiko, Tsutsui, Ryo, and Nakamura, Takashi

Subjects
*GAMMA ray bursts, *X-ray bursts, *GAMMA ray astronomy, *DARK energy, *MATHEMATICAL models
Abstract

We calibrated the peak energy–peak luminosity relation of gamma-ray bursts (GRBs; the so-called Yonetoku relation) using 33 events with redshift z < 1.62 without assuming any cosmological models. The luminosity distances to GRBs are estimated from those of large numbers of Type Ia supernovae with z < 1.755. This calibrated Yonetoku relation can be used as a new cosmic distance ladder towards higher redshifts. We determined the luminosity distances of 30 GRBs in 1.8 < z < 5.6 using the calibrated relation, and plotted the likelihood contour in the plane. We obtained for a flat universe. Because our method is free from the circularity problem, we can say that our universe in 1.8 < z < 5.6 is compatible with the so-called concordance cosmological model derived for z < 1.8. This suggests that the time variation of the dark energy is small or zero up to z∼ 6. [ABSTRACT FROM AUTHOR]

Published
2008
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47. Possible observational evidence for the θ−2 angular distribution of the opening half-angle of gamma-ray burst jets.

Author

Yonetoku, Daisuke, Yamazaki, Ryo, Nakamura, Takashi, and Murakami, Toshio

Subjects
*JETS (Nuclear physics), *GAMMA rays, *ELECTROMAGNETIC waves, *IONIZING radiation, *DISTRIBUTION (Probability theory), *NUCLEAR reactions, *ANGULAR correlations (Nuclear physics), *SCATTERING (Physics)
Abstract

We propose a method to estimate the jet opening half-angle of gamma-ray bursts (GRBs) using the spectral peak energy ( Ep)–peak luminosity relation (the so-called Yonetoku relation) as well as the Ep–collimation-corrected gamma-ray energy relation (the so-called Ghirlanda relation). For bursts with known jet break times and redshifts, we have compared the derived jet opening half-angle with that measured and found that the differences are within a factor of 2. We apply the method to 689 long GRBs. We have found that the distribution function of the derived jet opening half-angle obeys , although a lognormal fit is also possible. distribution is compatible with the structured jet model. From the distribution function we have found that the beaming correction for the rate of GRBs is ∼340, which means ∼10−5 yr−1 galaxy−1 or only one in 102 Type Ib/c supernovae. We have also found the evolution of the distribution function as a function of the redshift. [ABSTRACT FROM AUTHOR]

Published
2005
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48. Identification of subclasses of long gamma-ray bursts with cumulative light curve morphology.

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, and Takahashi, Keitaro

Subjects
GAMMA ray bursts, LIGHT curves, FIELD emission, COSMIC background radiation, STELLAR luminosity function, ASTROPHYSICS
Abstract

We have studied the morphology of the prompt emission of 36 long gamma-ray bursts with redshifts, well determined spectra by the Band model and 64 msec resolution light curves whose peak counts are 10 times larger than background fluctuations. We parametrize the morphology by the absolute deviation from their constant luminosity (ADCL) and find a clear gap in the distribution, which divides LGRBs into two subclasses: small-ADCL events (<0.17) and large ones (>0.17). We find that two subclasses are apparently separated in the spectral peak energy (Ep) - the peak luminosity (Lp) diagram. The Ep - Lp correlations both for small and large ADCL events are much tighter than the one for the whole events. [ABSTRACT FROM AUTHOR]

Published
2012
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49. The Fundamental Plane of Gamma-Ray Bursts and Its Prospect for Cosmology.

Author

Tsutsui, Ryo, Nakamura, Takashi, Yonetoku, Daisuke, Murakami, Toshio, and Takahashi, Keitaro

Subjects
GAMMA ray bursts, SUPERNOVAE, REDSHIFT, DARK energy, GALAXY clusters, EMISSIONS (Air pollution), METAPHYSICAL cosmology
Abstract

We showed the independence of the Epeak-Lp from Epeak-Eiso relations, and using Epeak, Lp, and Eiso as independent parameters, we found the fundamental plane of Gamma-ray bursts (GRBs). The fundamental plane of GRBs is the tightest correlation only using parameters of prompt emission of GRBs. Thus this correlation have the greatest potential for cosmology among other correlations obtained from GRBs. We calibrated by distances measured by supernovae Ia (SNe Ia). Then we estimated the distance toward high redshift GRBs (z>1.8) with about 30% errors. In this talk, we present cosmological constraints from high redshift GRBs which is as strong as from type Ia supernovae (SNe Ia). Then we show the current status of GRB cosmology and compare them with SNe Ia, clusters of galaxy, and CMB cosmologies. The constraint from high redshift GRBs are consistent with others. This might indicate that the time evolution of dark energy density is not large. Finally, we discuss the future prospect of GRB cosmology. [ABSTRACT FROM AUTHOR]

Published
2010
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50. Pop-III Star Formation Rate Inferred from Ep—Luminosity Relation of Gamma-Ray Bursts.

Author

Yonetoku, Daisuke

Subjects
*STAR formation, *STELLAR evolution, *GAMMA ray bursts, *GAMMA ray astronomy, *REDSHIFT, *METAPHYSICAL cosmology
Abstract

We estimate a GRB formation rate based on the relation between the spectral peak energy (Ep) and the peak luminosity. This relation is derived combining the data of Ep and the peak luminosities by BeppoSAX, BATSE, HETE-2, Integral, Konus, RHESSI and Swift, and it looks considerably tighter and more reliable than the relations suggested by the previous works. In this paper, we show the revised Ep–luminosity (Yonetoku) relation. Using the new Ep–luminosity relation, we estimate redshifts of the 689 GRBs without known distances in the BATSE catalog and derive a GRB formation rate as a function of the redshift. For the redshift range of 0

Published
2008
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