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301. Atomic data and spectral modeling constraints from high-resolution X-ray observations of the Perseus cluster with Hitomi*

Author

Collaboration, Hitomi, 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, 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, Hell, Natalie, 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, 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, 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, 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, Yamasaki, Noriko Y, Yamauchi, Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yatsu, Yoichi, Yonetoku, Daisuke, Zhuravleva, Irina, Zoghbi, Abderahmen, and Raassen, A J J

Abstract

The Hitomi Soft X-ray Spectrometer spectrum of the Perseus cluster, with ∼5 eV resolution in the 2–9 keV band, offers an unprecedented benchmark of the atomic modeling and database for hot collisional plasmas. It reveals both successes and challenges of the current atomic data and models. The latest versions of AtomDB/APEC (3.0.8), SPEX (3.03.00), and CHIANTI (8.0) all provide reasonable fits to the broad-band spectrum, and are in close agreement on best-fit temperature, emission measure, and abundances of a few elements such as Ni. For the Fe abundance, the APEC and SPEX measurements differ by 16%, which is 17 times higher than the statistical uncertainty. This is mostly attributed to the differences in adopted collisional excitation and dielectronic recombination rates of the strongest emission lines. We further investigate and compare the sensitivity of the derived physical parameters to the astrophysical source modeling and instrumental effects. The Hitomi results show that accurate atomic data and models are as important as the astrophysical modeling and instrumental calibration aspects. Substantial updates of atomic databases and targeted laboratory measurements are needed to get the current data and models ready for the data from the next Hitomi-level mission.

Published
2018
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302. Search for thermal X-ray features from the Crab nebula with the Hitomi soft X-ray spectrometer*

Author

Collaboration, Hitomi, 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, 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, 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, Sato, Toshiki, 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, Yamasaki, Noriko Y, Yamauchi, Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yatsu, Yoichi, Yonetoku, Daisuke, Zhuravleva, Irina, Zoghbi, Abderahmen, Tominaga, Nozomu, and Moriya, Takashi J

Abstract

The Crab nebula originated from a core-collapse supernova (SN) explosion observed in 1054 ad. 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 have been made for a massive shell that solves this discrepancy, but none has been detected. An alternative idea is that SN 1054 is an electron-capture (EC) explosion with a lower explosion energy by an order of magnitude than Fe-core-collapse SNe. X-ray imaging searches were performed for the plasma emission from the shell in the Crab outskirts to set a stringent upper limit on 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 on board the Hitomi satellite. By exploiting its superb energy resolution, we set an upper limit for emission or absorption features from as 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 ≲ 1 M⊙for a wide range of assumed shell radius, size, and plasma temperature values both in and out of collisional equilibrium. To compare with the observation, we further performed hydrodynamic simulations of the Crab SNR for two SN models (Fe-core versus EC) under two SN environments (uniform interstellar medium versus progenitor wind). We found that the observed mass limit can be compatible with both SN models if the SN environment has a low density of ≲ 0.03 cm−3(Fe core) or ≲ 0.1 cm−3(EC) for the uniform density, or a progenitor wind density somewhat less than that provided by a mass loss rate of 10−5M⊙yr−1at 20 km s−1for the wind environment.

Published
2018
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303. Hitomi observation of radio galaxy NGC 1275: The first X-ray microcalorimeter spectroscopy of Fe-Kα line emission from an active galactic nucleus*

Author

Collaboration, Hitomi, 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, 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, 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, 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, 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, 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, Yamasaki, Noriko Y, Yamauchi, Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yatsu, Yoichi, Yonetoku, Daisuke, Zhuravleva, Irina, Zoghbi, Abderahmen, and Kawamuro, Taiki

Abstract

The origin of the narrow Fe-Kα fluorescence line at 6.4 keV from active galactic nuclei has long been under debate; some of the possible sites are the outer accretion disk, the broad line region, a molecular torus, or interstellar/intracluster media. In 2016 February–March, we performed the first X-ray microcalorimeter spectroscopy with the Soft X-ray Spectrometer (SXS) on board the Hitomi satellite of the Fanaroff–Riley type I radio galaxy NGC 1275 at the center of the Perseus cluster of galaxies. With the high-energy resolution of ∼5 eV at 6 keV achieved by Hitomi/SXS, we detected the Fe-Kα line with ∼5.4 σ significance. The velocity width is constrained to be 500–1600 km s−1(FWHM for Gaussian models) at 90% confidence. The SXS also constrains the continuum level from the NGC 1275 nucleus up to ∼20 keV, giving an equivalent width of ∼20 eV for the 6.4 keV line. Because the velocity width is narrower than that of the broad Hα line of ∼2750 km s−1, we can exclude a large contribution to the line flux from the accretion disk and the broad line region. Furthermore, we performed pixel map analyses on the Hitomi/SXS data and image analyses on the Chandra archival data, and revealed that the Fe-Kα line comes from a region within ∼1.6 kpc of the NGC 1275 core, where an active galactic nucleus emission dominates, rather than that from intracluster media. Therefore, we suggest that the source of the Fe-Kα line from NGC 1275 is likely a low-covering-fraction molecular torus or a rotating molecular disk which probably extends from a parsec to hundreds of parsecs scale in the active galactic nucleus system.

Published
2018
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304. Hitomi X-ray studies of giant radio pulses from the Crab pulsar*

Author

Collaboration, Hitomi, 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, 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, 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, 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, Oshimizu, Kenya, 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, 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, Shiníchiro, 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, Shiníchiro, 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, Terasawa, Toshio, Sekido, Mamoru, Takefuji, Kazuhiro, Kawai, Eiji, Misawa, Hiroaki, Tsuchiya, Fuminori, Yamazaki, Ryo, Kobayashi, Eiji, Kisaka, Shota, and Aoki, Takahiro

Abstract

To search for giant X-ray pulses correlated with the giant radio pulses (GRPs) from the Crab pulsar, we performed a simultaneous observation of the Crab pulsar with the X-ray satellite Hitomi in the 2–300 keV band and the Kashima NICT radio telescope in the 1.4–1.7 GHz band with a net exposure of about 2 ks on 2016 March 25, just before the loss of the Hitomi mission. The timing performance of the Hitomi instruments was confirmed to meet the timing requirement and about 1000 and 100 GRPs were simultaneously observed at the main pulse and inter-pulse phases, respectively, and we found no apparent correlation between the giant radio pulses and the X-ray emission in either the main pulse or inter-pulse phase. All variations are within the 2 σ fluctuations of the X-ray fluxes at the pulse peaks, and the 3 σ upper limits of variations of main pulse or inter-pulse GRPs are 22% or 80% of the peak flux in a 0.20 phase width, respectively, in the 2–300 keV band. The values for main pulse or inter-pulse GRPs become 25% or 110%, respectively, when the phase width is restricted to the 0.03 phase. Among the upper limits from the Hitomi satellite, those in the 4.5–10 keV and 70–300 keV bands are obtained for the first time, and those in other bands are consistent with previous reports. Numerically, the upper limits of the main pulse and inter-pulse GRPs in the 0.20 phase width are about (2.4 and 9.3) × 10−11erg cm−2, respectively. No significant variability in pulse profiles implies that the GRPs originated from a local place within the magnetosphere. Although the number of photon-emitting particles should temporarily increase to account for the brightening of the radio emission, the results do not statistically rule out variations correlated with the GRPs, because the possible X-ray enhancement may appear due to a >0.02% brightening of the pulse-peak flux under such conditions.

Published
2018
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305. Hitomi observations of the LMC SNR N 132 D: Highly redshifted X-ray emission from iron ejecta*

Author

Collaboration, Hitomi, 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, 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, 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, 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, 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, Sato, Toshiki, 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, Yamasaki, Noriko Y, Yamauchi, Makoto, Yamauchi, Shigeo, Yaqoob, Tahir, Yatsu, Yoichi, Yonetoku, Daisuke, Zhuravleva, Irina, and Zoghbi, Abderahmen

Abstract

We present Hitomi observations of N 132 D, a young, X-ray bright, O-rich core-collapse supernova remnant in the Large Magellanic Cloud (LMC). Despite a very short observation of only 3.7 ks, the Soft X-ray Spectrometer (SXS) easily detects the line complexes of highly ionized S K and Fe K with 16–17 counts in each. The Fe feature is measured for the first time at high spectral resolution. Based on the plausible assumption that the Fe K emission is dominated by He-like ions, we find that the material responsible for this Fe emission is highly redshifted at ∼ 800 km s−1compared to the local LMC interstellar medium (ISM), with a 90% credible interval of 50–1500 km s−1if a weakly informative prior is placed on possible line broadening. This indicates (1) that the Fe emission arises from the supernova ejecta, and (2) that these ejecta are highly asymmetric, since no blueshifted component is found. The S K velocity is consistent with the local LMC ISM, and is likely from swept-up ISM material. These results are consistent with spatial mapping that shows the He-like Fe concentrated in the interior of the remnant and the S tracing the outer shell. The results also show that even with a very small number of counts, direct velocity measurements from Doppler-shifted lines detected in extended objects like supernova remnants are now possible. Thanks to the very low SXS background of ∼ 1 event per spectral resolution element per 100 ks, such results are obtainable during short pointed or slew observations with similar instruments. This highlights the power of high-spectral-resolution imaging observations, and demonstrates the new window that has been opened with Hitomi and will be greatly widened with future missions such as the X-ray Astronomy Recovery Mission (XARM) and Athena.

Published
2018
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306. XMM-NEWTON OBSERVATIONS OF THREE INTERACTING LUMINOUS INFRARED GALAXIES.

Author

Mudd, Dale, Mathur, Smita, Guainazzi, Matteo, Piconcelli, Enrico, Bianchi, Stefano, Komossa, S., Vignali, Cristian, Lanzuisi, Giorgio, Nicastro, Fabrizio, Fiore, Fabrizio, and Maiolino, Roberto

Subjects
GALAXIES, INFRARED radiation, GALACTIC evolution, ASTRONOMICAL research, ASTROPHYSICS research
Abstract

We investigate the X-ray properties of three interacting luminous infrared galaxy systems. In one of these systems, IRAS 18329+5950, we resolve two separate sources. A second and third source, IRAS 19354+4559 and IRAS 20550+1656, have only a single X-ray source detected. We compare the observed emission to point-spread function (PSF) profiles and determine that they are all consistent with the PSF, albeit with large uncertainties for some of our sources. We then model the spectra to determine soft (0.5-2 keV) and hard (2-10 keV) luminosities for the resolved sources and compare these to relationships found in the literature between infrared and X-ray luminosities for starburst galaxies. We obtain luminosities (0.5-10 keV) ranging from 1.7 to 7.3 × 1041 erg s–1 for our systems. These X-ray luminosities are consistent with predictions for star-formation-dominated sources and thus are most likely due to starbursts, but we cannot conclusively rule out active galactic nuclei. [ABSTRACT FROM AUTHOR]

Published
2014
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307. XMM–Newton unveils the type 2 nature of the BLRG 3C 445.

Author

Grandi, Paola, Guainazzi, Matteo, Cappi, Massimo, and Ponti, Gabriele

Subjects
*RADIO galaxies, *ACTIVE galaxies, *SEYFERT galaxies, *X-ray astronomy, *ASTRONOMY
Abstract

We present an observation of XMM–Newton that unambiguously reveals the ‘Seyfert 2’ nature of the broad line radio galaxy 3C 445. For the first time the soft excess of this source has been resolved. It consists of unobscured scattered continuum flux and emission lines, likely produced in a warm photoionized gas near the pole of an obscuring torus. The presence of circumnuclear (likely stratified) matter is supported by the complex obscuration of the nuclear region. 70 per cent of the nuclear radiation (first component) is indeed obscured by a column density ∼4 × 1023 cm−2, and 30 per cent (second component) is filtered by ∼7 × 1022 cm−2. The first component is nuclear radiation directly observed by transmission through the thicker regions. The second one is of more uncertain nature. If the observer has a deep view into the nucleus but near the edge of the torus, it could be light scattered by the inner wall of the torus and/or by photoionized gas within the broad line region observed through the thinner rim of the circumnuclear matter. [ABSTRACT FROM AUTHOR]

Published
2007
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308. Relativistic Iron Features from X-Ray Illuminated Spots and the Measure of the Black Hole Mass in AGN

Author

Matt, Giorgio, Bianchi, Stefano, Dovciak, Michal, Guainazzi, Matteo, and Karas, Vladimir

Abstract

Narrow spectral features in the 5–6 keV range were recently discovered in the X-ray spectra of a few Active Galactic Nuclei. We propose that these features originate from localized spots occurring on the surface of an accretion disc following its illumination by flares. Detailed calculations of the temporal and spectral properties of these features in our proposed model can be found in Dovčiak et al. (2004). Comparison of the computed profiles with observed features can help to estimate parameters of the system. In principle this method can provide a powerful tool to measure the mass of super-massive black holes in Active Galactic Nuclei. By comparing our calculations with the Chandra and XMM-Newton results, we show, however, that spectra from present generation X-ray satellites are not of good enough quality to fully exploit the method and determine the black hole mass with sufficient accuracy. This task has to be deferred to future missions with both large sensitivity and high energy resolution, such as Constellation-X and Xeus.

Published
2013
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309. Timescales Trips to PG Quasars: The Mkn 478 Case

Author

Guainazzi, Matteo, Loiseau, Nora, Matt, Giorgio, and Orr, Astrid

Abstract

The X-ray bright PG quasar PG 1440+356 (Mkn 478) was observed four times across 13 months with the XMM-Newton observatory. Flux variations with a dynamical range of a factor about 6 were observed in both the soft (E ≪ 1 keV) and the hard (E > 3 keV) X-ray band. However, large spectral variations are observed in the latter band only. We suggest that the X-ray emission in this object is due to Comptonization of kT ≃60 eV disk photons by a 20–50 keV plasma with a complex density structure. Analysis of the harmonic content of Mkn 478 light curves unveils a characteristic timescale ∼1 day, common to both energy bands. A longer (∼months) timescale is detected in the soft X-ray band only.

Published
2013
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310. Athena synergies in the multi-messenger and transient universe.

Author

Piro, Luigi, Ahlers, Markus, Coleiro, Alexis, Colpi, Monica, de Oña Wilhelmi, Emma, Guainazzi, Matteo, Jonker, Peter G., Namara, Paul Mc, Nichols, David A., O'Brien, Paul, Troja, Eleonora, Vink, Jacco, Aird, James, Amati, Lorenzo, Anand, Shreya, Bozzo, Enrico, Carrera, Francisco J., Fabian, Andrew C., Fryer, Christopher, and Hall, Evan

Subjects
*GAMMA ray bursts, *SUPERMASSIVE black holes, *BINARY black holes, *COSMIC rays, *GRAVITATIONAL waves, *EARLY stars, UNIVERSE
Abstract

In this paper we explore the scientific synergies between Athena and some of the key multi-messenger facilities that should be operative concurrently with Athena. These facilities include LIGO A+, Advanced Virgo+ and future detectors for ground-based observation of gravitational waves (GW), LISA for space-based observations of GW, IceCube and KM3NeT for neutrino observations, and CTA for very high energy observations. These science themes encompass pressing issues in astrophysics, cosmology and fundamental physics such as: the central engine and jet physics in compact binary mergers, accretion processes and jet physics in Super-Massive Binary Black Holes (SMBBHs) and in compact stellar binaries, the equation of state of neutron stars, cosmic accelerators and the origin of Cosmic Rays (CRs), the origin of intermediate and high-Z elements in the Universe, the Cosmic distance scale and tests of General Relativity and the Standard Model. Observational strategies for implementing the identified science topics are also discussed. A significant part of the sources targeted by multi-messenger facilities is of transient nature. We have thus also discussed the synergy of Athena with wide-field high-energy facilities, taking THESEUS as a case study for transient discovery. This discussion covers all the Athena science goals that rely on follow-up observations of high-energy transients identified by external observatories, and includes also topics that are not based on multi-messenger observations, such as the search for missing baryons or the observation of early star populations and metal enrichment at the cosmic dawn with Gamma-Ray Bursts (GRBs). [ABSTRACT FROM AUTHOR]

Published
2022
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311. The X-ray view of optically selected dual AGN

Author

Alessandra De Rosa, Cristian Vignali, Paola Severgnini, Stefano Bianchi, Tamara Bogdanović, Maria Charisi, Matteo Guainazzi, Zoltan Haiman, S Komossa, Zsolt Paragi, Miguel Perez-Torres, Enrico Piconcelli, Lorenzo Ducci, Manali Parvatikar, Roberto Serafinelli, De Rosa, Alessandra, Vignali, Cristian, Severgnini, Paola, Bianchi, Stefano, Bogdanović, Tamara, Charisi, Maria, Guainazzi, Matteo, Haiman, Zoltan, Komossa, S, Paragi, Zsolt, Perez-Torres, Miguel, Piconcelli, Enrico, Ducci, Lorenzo, Parvatikar, Manali, and Serafinelli, Roberto

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies
Abstract

We present a study of optically selected dual AGN with projected separations of 3--97~kpc. Using multi-wavelength (MWL) information (optical, X-rays, mid-IR), we characterized the intrinsic nuclear properties of this sample and compared them with those of isolated systems. Among the 124 X-ray detected AGN candidates, 52 appear in pairs and 72 as single X-ray sources. Through MWL analysis, we confirmed the presence of the AGN in a fraction >80\% of the detected targets in pairs (42 over 52). X-ray spectral analysis confirms the trend of increasing AGN luminosity with decreasing separation, suggesting that mergers may have contributed in triggering more luminous AGN. Through X/mid-IR ratio $vs$ X-ray colors, we estimated a fraction of Compton-thin AGN (with 10$^{22}$ cm$^{-2}$ $$10$^{24}$ cm$^{-2}$) sources. These fractions of obscured sources are larger than those found in samples of isolated AGN, confirming that pairs of AGN show higher obscuration. This trend is further confirmed by comparing the de-reddened [O\ III] emission with the observed X-ray luminosity. However, the derived fraction of Compton-thick sources in this sample at early stage of merging is lower than reported for late-merging dual-AGN samples. Comparing N$_{\rm H}$ from X-rays with that derived from E(B-V) from Narrow Line Regions, we find that the absorbing material is likely associated with the torus or the Broad Line Regions. We also explored the X-ray detection efficiency of dual-AGN candidates, finding that, when observed properly (at on-axis positions and with long exposures), X-ray data represent a powerful way to confirm and investigate dual-AGN systems., 12 pages, 4 figures. Accepted for publication in MNRAS

Published
2022

312. The Athena space X‐ray observatory and the astrophysics of hot plasma†.

Author

Barret, Didier, Decourchelle, Anne, Fabian, Andy, Guainazzi, Matteo, Nandra, Kirpal, Smith, Randall, and den Herder, Jan‐Willem

Subjects
*ASTROPHYSICS, *X-rays, *PLASMA astrophysics, *HIGH temperature plasmas, *X-ray spectroscopy, *GALACTIC X-ray sources, *ACCRETION (Astrophysics)
Abstract

The properties (temperature, density, chemical composition, velocity) of hot astrophysical plasma and the physical processes affecting them (heating/cooling, turbulence, shocks, acceleration) can be probed by high‐resolution X‐ray spectroscopy, to be complemented by high‐spatial‐resolution imaging. The paper presents the status of the European Space Agency's Advanced Telescope for High Energy Astrophysics (Athena) mission, particularly focusing on the science performance of its two focal‐plane instruments for studies of extended X‐ray sources: the wide‐field imager and the X‐ray integral field unit. This paper then provides a brief summary of the breakthroughs expected with Athena on the astrophysics of hot plasma, building on the vast heritage of the discoveries and revolutionary results obtained by Chandra and XMM‐Newton in this field. As of November 12, 2019, Athena successfully concluded its feasibility study, and has since then moved into the definition phase, with a launch date scheduled in the early 2030s. [ABSTRACT FROM AUTHOR]

Published
2020
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313. Wind-luminosity evolution in NLS1 AGN 1H 0707−495

Author

Didier Barret, Dominic J. Walton, Michael Parker, Yerong Xu, Andrew C. Fabian, P. Kosec, Giancarlo Cusumano, Stefano Bianchi, Matteo Guainazzi, Ciro Pinto, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Xu, Yerong, Pinto, Ciro, Bianchi, Stefano, Kosec, Peter, Parker, Michael L, Walton, Dominic J, Fabian, Andrew C, Guainazzi, Matteo, Barret, Didier, and Cusumano, Giancarlo

Subjects
Active galactic nucleus, Astrophysics::High Energy Astrophysical Phenomena, black hole physics, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Spectral line, Luminosity, accretion, Ionization, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Accretion (meteorology), 010308 nuclear & particles physics, Astronomy and Astrophysics, Radius, accretion discs, galaxies: Seyfert, Space and Planetary Science, X-rays: individual: 1H 0707−495, Outflow, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

Ultra-fast outflows (UFOs) have been detected in the high-quality X-ray spectra of a number of active galactic nuclei (AGN) with fairly high accretion rates and are thought to significantly contribute to the AGN feedback. After a decade of dedicated study, their launching mechanisms and structure are still not well understood, but variability techniques may provide useful constraints. In this work, therefore, we perform a flux-resolved X-ray spectroscopy on a highly accreting and variable NLS1 AGN, 1H 0707-495, using all archival XMM-Newton observations to study the structure of the UFO. We find that the wind spectral lines weaken at higher luminosities, most likely due to an increasing ionization parameter as previously found in a few similar sources. Instead, the velocity is anticorrelated with the luminosity, which is opposite to the trend observed in the NLS1 IRAS 13224-3809. Furthermore, the detection of the emission lines, which are not observed in IRAS 13224-3809, indicates a wind with a larger opening angle in 1H 0707-495, presumably due to a higher accretion rate. The emitting gas is found to remain broadly constant with the luminosity. We describe the variability of the wind with a scenario where the strong radiation extends the launch radius outwards and shields the outer emitting gas, similarly to super-Eddington compact objects, although other possible explanations are discussed. Our work provides several hints for a multi-phase outflow in 1H 0707-495., Comment: 20 pages, 9 figures, accepted for publication in MNRAS

Published
2021

314. The quest for dual and binary supermassive black holes: A multi-messenger view

Author

Rubén Herrero-Illana, Zoltan Haiman, Bernd Husemann, Pedro R. Capelo, Lisa Steinborn, Stefano Bianchi, Enrico Piconcelli, Margherita Giustini, Miguel A. Pérez-Torres, Alberto Sesana, Monica Colpi, S. Komossa, Kazushi Iwasawa, Sándor Frey, Davide Lena, Maria Charisi, Nora Loiseau, Zsolt Paragi, Elisabeta Lusso, Matteo Guainazzi, Cristian Vignali, Massimo Dotti, Jessie C. Runnoe, Tamara Bogdanovic, Krisztina É. Gabányi, Lucio Mayer, Noelia Herrera Ruiz, Marta Volonteri, Luciano del Valle, Alessandra De Rosa, Centros de Excelencia Severo Ochoa, INSTITUTO DE ASTROFISICA DE ANDALUCIA (IAA), SEV-2017-0709, Unidad de Excelencia Científica María de Maeztu Instituto de Ciencias del Cosmos (ICCUB), MDM-2014-0369, Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737, Lena, D. [0000-0003-4184-6152], Loiseau, N. [0000-0001-5471-3776], Haiman, Z. [0000-0003-3633-5403], De Rosa, A. [0000-0001-5668-6863], Husemann, B. [0000-0003-2901-6842], Agenzia Spaziale Italiana (ASI), Istituto Nazionale Astrofisica (INAF), National Aeronautics and Space Administration (NASA), Hungarian Scientific Research Fund (OTKA), Hungarian Academy of Sciences (MTA), Deutsche Forschungsgemeinschaft (DFG), European Union COFUND/Durham Junior Research Fellowship (EU), European Research Council (ERC), Swiss National Science Foundation (SNSF), Federal Ministry of Education & Research (BMBF), Ministerio de Economía y Competitividad (MINECO), Comunidad de Madrid, Agencia Estatal de Investigación (AEI), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Agenzia Spaziale Italiana, National Aeronautics and Space Administration (US), Hungarian Academy of Sciences, National Research, Development and Innovation Office (Hungary), German Research Foundation, European Commission, European Research Council, Ministerio de Economía y Competitividad (España), Swiss National Science Foundation, National Science Foundation (US), Hungarian National Research, New National Excellence Program of the Ministry for Innovation and Technology, Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, Centro de Excelencia Científica Severo Ochoa Instituto de Astrofísica de Andalucía CSIC, Unidad de Excelencia Científica María de Maeztu Instituto de Ciencias del Coscmos de la Universidad de Barcelona, 'Programa de Atraccion de Talento' of the Comunidad de Madrid, 2018-T1/TIC-11733, De Rosa, A, Vignali, C, Bogdanovic, T, Capelo, P, Charisi, M, Dotti, M, Husemann, B, Lusso, E, Mayer, L, Paragi, Z, Runnoe, J, Sesana, A, Steinborn, L, Bianchi, S, Colpi, M, del Valle, L, Frey, S, Gabanyi, K, Giustini, M, Guainazzi, M, Haiman, Z, Herrera Ruiz, N, Herrero-Illana, R, Iwasawa, K, Komossa, S, Lena, D, Loiseau, N, Perez-Torres, M, Piconcelli, E, Volonteri, M, Rosa, Alessandra De, Vignali, Cristian, Bogdanović, Tamara, Capelo, Pedro R., Charisi, Maria, Dotti, Massimo, Husemann, Bernd, Lusso, Elisabeta, Mayer, Lucio, Paragi, Zsolt, Runnoe, Jessie, Sesana, Alberto, Steinborn, Lisa, Bianchi, Stefano, Colpi, Monica, Valle, Luciano Del, Frey, Sándor, Gabányi, Krisztina É., Giustini, Margherita, Guainazzi, Matteo, Haiman, Zoltan, Ruiz, Noelia Herrera, Herrero-Illana, Rubén, Iwasawa, Kazushi, Komossa, S., Lena, Davide, Loiseau, Nora, Perez-Torres, Miguel, Piconcelli, Enrico, Volonteri, Marta, De Rosa A., Vignali C., Bogdanovic T., Capelo P.R., Charisi M., Dotti M., Husemann B., Lusso E., Mayer L., Paragi Z., Runnoe J., Sesana A., Steinborn L., Bianchi S., Colpi M., del Valle L., Frey S., Gabanyi K.E., Giustini M., Guainazzi M., Haiman Z., Herrera Ruiz N., Herrero-Illana R., Iwasawa K., Komossa S., Lena D., Loiseau N., Perez-Torres M., Piconcelli E., and Volonteri M.

Subjects
Galaxies: active, Galaxies: interactions, Galaxies: nuclei, gravitational waves, Quasars: supermassive black holes, Active galactic nucleus, active [Galaxies], Electromagnetic spectrum, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Binary number, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, interactions [Galaxies], 01 natural sciences, 7. Clean energy, Cosmology, Gravitational waves, General Relativity and Quantum Cosmology, 0103 physical sciences, 010303 astronomy & astrophysics, gravitational wave, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Supermassive black hole, 010308 nuclear & particles physics, Gravitational wave, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Galaxy, Redshift, 13. Climate action, Space and Planetary Science, Galaxies: interaction, Astrophysics of Galaxies (astro-ph.GA), nuclei [Galaxies], Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], supermassive black holes [Quasars]
Abstract

69 pages, 21 figures. Accepted for publication in New Astronomy Reviews © 2020 Elsevier B.V., The quest for binary and dual supermassive black holes (SMBHs) at the dawn of the multi-messenger era is compelling. Detecting dual active galactic nuclei (AGN) -- active SMBHs at projected separations larger than several parsecs -- and binary AGN -- probing the scale where SMBHs are bound in a Keplerian binary -- is an observational challenge. The study of AGN pairs (either dual or binary) also represents an overarching theoretical problem in cosmology and astrophysics. The AGN triggering calls for detailed knowledge of the hydrodynamical conditions of gas in the imminent surroundings of the SMBHs and, at the same time, their duality calls for detailed knowledge on how galaxies assemble through major and minor mergers and grow fed by matter along the filaments of the cosmic web. This review describes the techniques used across the electromagnetic spectrum to detect dual and binary AGN candidates and proposes new avenues for their search. The current observational status is compared with the state-of-the-art numerical simulations and models for formation of dual and binary AGN. Binary SMBHs are among the loudest sources of gravitational waves (GWs) in the Universe. The search for a background of GWs at nHz frequencies from inspiralling SMBHs at low redshifts, and the direct detection of signals from their coalescence by the Laser Interferometer Space Antenna in the next decade, make this a theme of major interest for multi-messenger astrophysics. This review discusses the future facilities and observational strategies that are likely to significantly advance this fascinating field.© 2020 Elsevier B.V., All authors acknowledge the hospitality of the Lorentz Center for international workshops (Leiden, The Netherlands), where the idea of this work was born, and acknowledge the support of the International Space Science Institute (ISSI Bern, Switzerland), where the collaboration was originated. We thank the reviewers for having provided valuable and constructive comments that improved the clarity of the manuscript, and J.E. Barnes, L. Blecha, M. Eracleous, B.D. Farris, H. Fu, X. Liu, R. Pfeifle, L.C. Popovic, C. Ricci, S. Rodriguez, S. Tang, G. B. Taylor for their kind permission to reuse figures from their publications. ADR, CV and SB acknowledge financial support from ASI under grant ASI-INAF I/037/12/0 , and from the agreement ASI-INAF n. 2017-14-H.O . TB acknowledges support by the National Aeronautics and Space Administration under Grant No. NNX15AK84G and 80NSSC19K0319 issued through the Astrophysics Theory Program and by the Research Corporation for Science Advancement through a Cottrell Scholar Award. SF and KÉG thank the Hungarian National Research, Development, and Innovation Office ( OTKA NN110333 ) for support. KÉG was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences and by the ÚNKP-19-4 New National Excellence Program of the Ministry for Innovation and Technology. BH acknowledges financial support by the DFG grant GE625/17-1 . EL is supported by a European Union COFUND/Durham Junior Research Fellowship (under EU grant agreement no. 609412). DL acknowledges support from the European Research Council (ERC) under grant 647208 (PI Jonker). AS is supported by the ERC CoG grant 818691 (B Massive). MGi is supported by the “Programa de Atracción de Talento” of the Comunidad de Madrid grant 2018-T1/TIC-11733 for the project: “Unveiling Black Hole Winds from Space”, and by the Spanish State Research Agency (AEI) grant MDM-2017-0737 Unidad de Excelencia “María de Maeztu” - Centro de Astrobiología (INTA-CSIC). PRC and LM acknowledge support from the Swiss National Science Foundation under the Grant 200020_178949 . MC acknowledges support from the National Science Foundation (NSF) NANOGrav Physics Frontier Center, award number 1430284 . NHR acknowledges support from the BMBF Verbundforschung under FKZ: 05A17PC1 and FKZ: 05A17PC2. ZH acknowledges support from NASA grants NNX17AL82G and 80NSSC19K0149 and NSF grant 1715661 . KI acknowledges support by the Spanish MINECO under grant AYA2016-76012-C3-1-P and MDM-2014-0369 of ICCUB (Unidad de Excelencia ’María de Maeztu’). MPT acknowledges financial support from the Spanish MCIU through the “Center of Excellence Severo Ochoa” award for the Instituto de Astrofísica de Andalucía ( SEV-2017-0709 ) and through the MINECO grants AYA2012-38491-C02-02 and AYA2015-63939-C2-1-P .

Published
2019

315. Evidence for Radiation Pressure Compression in the X-ray Narrow Line Region of Seyfert galaxies

Author

Stefano Bianchi, Ari Laor, Jonathan Stern, Matteo Guainazzi, Ehud Behar, Bianchi, Stefano, Guainazzi, Matteo, Laor, Ari, Stern, Jonathan, and Behar, Ehud

Subjects
Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Range (particle radiation), Active galactic nucleus, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Spectral line, Galaxy, Ionizing radiation, Radiation pressure, Space and Planetary Science, Ionization, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Astrophysics - High Energy Astrophysical Phenomena, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Line (formation)
Abstract

The observed spatial and kinematic overlap between soft X-ray emission and the Narrow Line Region (NLR) in obscured Active Galactic Nuclei (AGN) yields compelling evidence that relatively low-density gas co-exists with higher density gas on scales as large as 100s of pc. This is commonly interpreted as evidence for a constant gas pressure multiphase medium, likely produced by thermal instability. Alternatively, Radiation Pressure Compression (RPC) also leads to a density distribution, since a gas pressure (and hence density) gradient must arise within each cloud to counteract the incident ionising radiation pressure. RPC leads to a well-defined ionization distribution, and a Differential Emission Measure (DEM) distribution with a universal slope of $\sim-0.9$, weakly dependent on the gas properties and the illuminating radiation field. In contrast, a multiphase medium does not predict the form of the DEM. The observed DEMs of obscured AGN with XMM-Newton RGS spectra (the CHRESOS sample) are in striking agreement with the predicted RPC DEM, providing a clear signature that RPC is the dominant mechanism for the observed range of densities in the X-ray NLR. In contrast with the constant gas pressure multiphase medium, RPC further predicts an increasing gas pressure with decreasing ionization, which can be tested with future X-ray missions using density diagnostics., Comment: 13 pages, 8 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society Main Journal

Published
2019

316. The quest for dual and binary supermassive black holes: A multi-messenger view.

Author

De Rosa, Alessandra, Vignali, Cristian, Bogdanović, Tamara, Capelo, Pedro R., Charisi, Maria, Dotti, Massimo, Husemann, Bernd, Lusso, Elisabeta, Mayer, Lucio, Paragi, Zsolt, Runnoe, Jessie, Sesana, Alberto, Steinborn, Lisa, Bianchi, Stefano, Colpi, Monica, del Valle, Luciano, Frey, Sándor, Gabányi, Krisztina É., Giustini, Margherita, and Guainazzi, Matteo

Subjects
*BINARY black holes, *PHYSICAL cosmology, *ACTIVE galactic nuclei, *GRAVITATIONAL waves, *ASTROPHYSICS, *SUPERMASSIVE black holes, *GALAXY mergers
Abstract

The quest for binary and dual supermassive black holes (SMBHs) at the dawn of the multi-messenger era is compelling. Detecting dual active galactic nuclei (AGN) – active SMBHs at projected separations larger than several parsecs – and binary AGN – probing the scale where SMBHs are bound in a Keplerian binary – is an observational challenge. The study of AGN pairs (either dual or binary) also represents an overarching theoretical problem in cosmology and astrophysics. The AGN triggering calls for detailed knowledge of the hydrodynamical conditions of gas in the imminent surroundings of the SMBHs and, at the same time, their duality calls for detailed knowledge on how galaxies assemble through major and minor mergers and grow fed by matter along the filaments of the cosmic web. This review describes the techniques used across the electromagnetic spectrum to detect dual and binary AGN candidates and proposes new avenues for their search. The current observational status is compared with the state-of-the-art numerical simulations and models for formation of dual and binary AGN. Binary SMBHs are among the loudest sources of gravitational waves (GWs) in the Universe. The search for a background of GWs at nHz frequencies from inspiralling SMBHs at low redshifts, and the direct detection of signals from their coalescence by the Laser Interferometer Space Antenna in the next decade, make this a theme of major interest for multi-messenger astrophysics. This review discusses the future facilities and observational strategies that are likely to significantly advance this fascinating field. [ABSTRACT FROM AUTHOR]

Published
2019
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317. Unveiling multiple AGN activity in galaxy mergers

Author

Emma Kun, Stefanie Komossa, Bernd Husemann, Zsolt Paragi, Stefano Bianchi, Kevin Schawinski, Miguel A. Pérez-Torres, Tamara Bogdanovic, Jochen Heidt, Nora Loiseau, Cristian Vignali, Rubén Herrero-Illana, A. De Rosa, Roberto Decarli, Enrico Piconcelli, Matteo Guainazzi, DE ROSA, Alessandra, Bianchi, Stefano, Bogdanović, T., Decarli, R., Heidt, J., Herrero Illana, R., Husemann, B., Komossa, S., Kun, E., Loiseau, N., Guainazzi, Matteo, Paragi, Z., Perez Torres, M., Piconcelli, E., Schawinski, K., Vignali, C., De Rosa, A, Bianchi, S., Herrero-Illana, R., Guainazzi, M., and Perez-Torres, M.

Subjects
Active galactic nucleus, Seyfert–galaxie, Astrophysics::High Energy Astrophysical Phenomena, active–galaxie, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy merger, 01 natural sciences, 0103 physical sciences, Tidal force, Seyfert–galaxies, Emission spectrum, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Star formation, galaxie, Astronomy and Astrophysics, Astronomy and Astrophysic, Astrophysics - Astrophysics of Galaxies, Galaxy, Black hole, interactions–X-ray, Compact group, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics - High Energy Astrophysical Phenomena
Abstract

In this paper we present an overview of the MAGNA (Multiple AGN Activity) project aiming at a comprehensive study of multiple supemassive black hole systems. With the main goal to characterize the sources in merging systems at different stages of evolution, we selected a sample of objects optically classified as multiple systems on the basis of emission line diagnostics and started a massive multiband observational campaign. Here we report on the discovery of the exceptionally high AGN density compact group SDSS~J0959+1259. A multiband study suggests that strong interactions are taking place among its galaxies through tidal forces, therefore this system represents a case study for physical mechanisms that trigger nuclear activity and star formation. We also present a preliminary analysis of the multiple AGN system SDSS~J1038+3921.}, Comment: Proceedings paper for "XMM-Newton: The Next Decade" (held in 2016 May); accepted to be published in Astronomische Nachrichten / Astronomical Notes (AN)

Published
2016
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318. The nature of the torus in the heavily obscured AGN Markarian 3: an X-ray study

Author

W. N. Brandt, P. Arévalo, Andrea Marinucci, Christopher S. Reynolds, C. J. Hailey, Stefano Bianchi, Daniel Stern, Giorgio Matt, Claudio Ricci, Fiona A. Harrison, Murray Brightman, Guido Risaliti, W. W. Zhang, J. Svoboda, C. B. Markwardt, Dominic J. Walton, Hisamitsu Awaki, William W. Craig, K. Forster, Franz E. Bauer, A. L. Longinotti, M. Koss, Finn Erland Christensen, Matteo Guainazzi, S. E. Boggs, Guainazzi, Matteo, Risaliti, G., Awaki, H., Arevalo, P., Bauer, F. E., Bianchi, Stefano, Boggs, S. E., Brandt, W. N., Brightman, M., Christensen, F. E., Craig, W. W., Forster, K., Hailey, C. J., Harrison, F., Koss, M., Longinotti, A., Markwardt, C., Marinucci, Andrea, Matt, Giorgio, Reynolds, C. S., Ricci, C., Stern, D., Svoboda, J., Walton, D., and Zhang, W.

Subjects
galaxie [X-rays], Seyfert [Galaxies], X-rays: individual: Markarian 3, active [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Occultation, Ionization, 0103 physical sciences, individual: Markarian 3 [X-rays], 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Compton scattering, X-ray, Astronomy, Astronomy and Astrophysics, Torus, Astronomy and Astrophysic, galaxies: Seyfert, Galaxy, galaxies [X-rays], X-rays: galaxies, Radiation pressure, Space and Planetary Science, Sublimation (phase transition), Astrophysics - High Energy Astrophysical Phenomena
Abstract

著者人数: 25名, Accepted: 2016-04-28, 資料番号: SA1160281000

Published
2016
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319. 3C 273 WITHNuSTAR: UNVEILING THE ACTIVE GALACTIC NUCLEUS

Author

Dominic J. Walton, Karl Forster, William W. Craig, Andrew C. Fabian, Giorgio Matt, Fiona A. Harrison, Charles J. Hailey, Brian W. Grefenstette, Greg Madejski, S. E. Boggs, Laura Brenneman, Finn Erland Christensen, Matteo Guainazzi, Felix Fürst, Daniel Stern, Kristin K. Madsen, Krzysztof Nalewajko, William W. Zhang, Roland Walter, David R. Ballantyne, Madsen, Kristin K., Fürst, Felix, Walton, Dominic J., Harrison, Fiona A., Nalewajko, Krzysztof, Ballantyne, David R., Boggs, Steve E., Brenneman, Laura W., Christensen, Finn E., Craig, William W., Fabian, Andrew C., Forster, Karl, Grefenstette, Brian W., Guainazzi, Matteo, Hailey, Charles J., Madejski, Greg M., Matt, Giorgio, Stern, Daniel, Walter, Roland, and Zhang, William W.

Subjects
Physics, Nuclear and High Energy Physics, Photon, Active galactic nucleus, Astrophysics::High Energy Astrophysical Phenomena, Extrapolation, Astronomy and Astrophysics, Quasar, Astrophysics, individual (3C 273) [X-rays], Power law, Accretion (astrophysics), Spectral line, Space and Planetary Science, individual (3C 273) [quasars], Fermi Gamma-ray Space Telescope
Abstract

We present results from a 244 ks NuSTAR observation of 3C 273 obtained during a cross-calibration campaign with the Chandra, INTEGRAL, Suzaku, Swift, and XMM-Newton observatories. We show that the spectrum, when fit with a power-law model using data from all observatories except INTEGRAL over the 1-78 keV band, leaves significant residuals in the NuSTAR data between 30 and 78 keV. The NuSTAR 3-78 keV spectrum is well. described by an exponentially cutoff power law (Γ = 1.646± 0.006, Ecutoff = 202-34 +51 keV) with a weak reflection component from cold, dense material. There is also evidence for a weak (EW = 23 ± 11 eV) neutral iron line. We interpret these features as arising from coronal emission plus reflection off an accretion disk or distant material. Beyond 80 keV INTEGRAL data show clear excess flux relative to an extrapolation of the active galactic nucleus model fit to NuSTAR. This high-energy power. law is consistent with the presence of a beamed jet, which begins to dominate over emission from the inner accretion flow at 30-40 keV. Modeling the jet locally (in the NuSTAR + INTEGRAL band) as a power. law, we find that the coronal component is fit by ΓAGN = 1.638 ± 0.045, Ecutoff = 47 ± 15 keV, and jet photon index by Γjet = 1.05 ± 0.4. We also consider Fermi/LAT observations of 3C 273, and here the broadband spectrum of the jet can be described by a log-parabolic model, peaking at ∼ 2 MeV. Finally, we investigate the spectral variability in the NuSTAR band and find an inverse correlation between flux and Gamma.

Published
2015

320. A multiwavelength map of the nuclear region of NGC7582

Author

Stefano Bianchi, Enrico Piconcelli, Marco Chiaberge, Matteo Guainazzi, Bianchi, Stefano, Chiaberge, Marco, Piconcelli, Enrico, and Guainazzi, Matteo

Subjects
Physics, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Torus, Photoionization, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Dust lane, Space and Planetary Science, Coincident, Ionization, Absorption (electromagnetic radiation), Astrophysics::Galaxy Astrophysics
Abstract

We performed a detailed analysis of the Chandra and HST images of the Seyfert 2 galaxy, NGC7582. The dust lane, as mapped by the HST NIR and optical images, strongly influences the morphology of the soft X-ray emission, being spatially coincident with excess of X-ray absorption. Two 'hot spots', i.e. regions where emission from higher ionization stages of O and Ne is stronger, are observed in the soft X-ray image. They can be tracers of variations of the ionization parameter, even if, at least for one of them, absorption may be the dominant effect. The positions of the `hot spots' suggest that they are not affected by the star-formation regions observed with HST, being located far away from them. Therefore, the starburst does not seem to play an important role in the photoionization of the soft X-ray emitting gas. The resulting picture is consistent with modified unification scenarios, where the Compton-thick torus coexists with a large-scale Compton-thin material associated with the dust lane and circumnuclear gas is photoionized by the AGN along torus-free lines of sight., Comment: 6 pages, 6 figures, accepted for publication in MNRAS

Published
2006
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321. Relativistic iron features from X-ray illuminated spots and the measure of the black hole mass in AGN

Author

M. Dovciak, Matteo Guainazzi, Stefano Bianchi, Giorgio Matt, Vladimir Karas, Matt, Giorgio, Bianchi, Stefano, Dovčiak, Michal, Guainazzi, Matteo, and Karas, Vladimir

Subjects
Black hole, Physics, Supermassive black hole, Active galactic nucleus, Binary black hole, Physics and Astronomy (miscellaneous), Intermediate-mass black hole, Astrophysics::High Energy Astrophysical Phenomena, Reverberation mapping, Stellar black hole, Astrophysics, Schwarzschild radius
Abstract

Narrow spectral features in the 5-6 keV range were recently discovered in the X-ray spectra of a few Active Galactic Nuclei. We propose that these features originate from localized spots occurring on the surface of an accretion disc following its illumination by flares. Detailed calculations of the temporal and spectral properties of these features in our proposed model can be found in Dovciak et al. (2004). Comparison of the computed profiles with observed features can help to estimate parameters of the system. In principle this method can provide a powerful tool to measure the mass of super-massive black holes in Active Galactic Nuclei. By comparing our calculations with the Chandra and XMM-Newton results, we show, however, that spectra from present generation X-ray satellites are not of good enough quality to fully exploit the method and determine the black hole mass with sufficient accuracy. This task has to be deferred to future missions with both large sensitivity and high energy resolution, such as Constellation-X and Xeus. §1. The method Relativistic iron line profiles may provide a powerful tool to measure the mass of the black hole in Active Galactic Nuclei (AGNs) and Galactic black hole systems. To this aim, Stella (1990) proposed to use temporal changes in the line profile following variations of the illuminating primary source. Along the same line, Matt and Perola (1992) proposed to employ, instead, variations of the integrated line properties such as equivalent width, centroid energy and line width. These methods are very similar conceptually to the classical reverberation mapping method, widely and successfully applied to optical broad lines in AGNs. Sufficiently long monitoring of the continuum and of the line emission is however required, as well as large enough signal-to-noise ratio, and in practice these methods have not provided many results yet. A simple, direct and potentially robust way to measure the black hole mass would be available if the line emission originates at a given radius and azimuth, as expected if the disc illumination is provided by a localized flare just above the disc (possibly due to magnetic reconnection), rather than a central illuminator or an extended corona. If the resulting 'hot spot' co-rotates with the disc and lives for at least a significant part of an orbit, by fitting the light curve and centroid energy of

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