================================ Papers ================================ Papers --------------------------------------------------------------------------- ----------------------------------------------- **JASMINE: Near-Infrared Astrometry and Time Series Photometry Science** ----------------------------------------------- Daisuke Kawata, **Hajime Kawahara**, Naoteru Gouda, Nathan J. Secrest, et al., `arXiv:2307.05666 `_, Accepted in PASJ. ----------------------------------------------- **A spectroscopic thermometer: individual vibrational band spectroscopy with the example of OH in the atmosphere of WASP-33b** ----------------------------------------------- Sam O.M. Wright, Stevanus K. Nugroho, Matteo Brogi, Neale P. Gibson, Ernst J. W. de Mooij, Ingo Waldmann, Jonathan Tennyson, **Hajime Kawahara**, Masayuki Kuzuhara, Teruyuki Hirano, Takayuki Kotani, Yui Kawashima, Kento Masuda, Jayne L. Birkby, Chris A. Watson, Motohide Tamura, Konstanze Zwintz, Hiroki Harakawa, Tomoyuki Kudo, Klaus Hodapp, Shane Jacobson, Mihoko Konishi, Takashi Kurokawa, Jun Nishikawa, Masashi Omiya, Takuma Serizawa, Akitoshi Ueda, Sébastien Vievard, Sergei N. Yurchenko , `arXiv:2305.11071 `_, **Accepted by AJ (2023)** ----------------------------------------------- **Fast optical flares from M dwarfs detected by a one-second-cadence survey with Tomo-e Gozen** ----------------------------------------------- Masataka Aizawa, Kojiro Kawana, Kazumi Kashiyama, Ryou Ohsawa, **Hajime Kawahara**, Fumihiro Naokawa, Tomoyuki Tajiri, Noriaki Arima, Hanchun Jiang, Tilman Hartwig, Kotaro Fujisawa, Toshikazu Shigeyama, Ko Arimatsu, Mamoru Doi, Toshihiro Kasuga, Naoto Kobayashi, Sohei Kondo, Yuki Mori, Shin-ichiro Okumura, Satoshi Takita, Shigeyuki Sako, `arXiv:2206.12847 `_, **PASJ 74, 1069 (2022)** ----------------------------------------------- **A Super-Earth Orbiting Near the Inner Edge of the Habitable Zone around the M4.5-dwarf Ross 508** ----------------------------------------------- Hiroki Harakawa, Takuya Takarada, Yui Kasagi, Teruyuki Hirano, Takayuki Kotani, Masayuki Kuzuhara, Masashi Omiya, **Hajime Kawahara** et al. `arXiv:2205.11986 `_, **PASJ 74, 904 (2022)** ----------------------------------------------- **Global Mapping of Surface Composition on an Exo-Earth Using Sparse Modeling** ----------------------------------------------- Atsuki Kuwata, **Hajime Kawahara**, Masataka Aizawa, Takayuki Kotani, Motohide Tamura `arXiv:2204.01996 `_, **ApJ 930, 162 (2022)** ----------------------------------------------- **Images of Embedded Jovian Planet Formation At A Wide Separation Around AB Aurigae** ----------------------------------------------- Thayne Currie, Kellen Lawson, Glenn Schneider, Wladimir Lyra, John Wisniewski, Carol Grady, Olivier Guyon, Motohide Tamura, Takayuki Kotani, **Hajime Kawahara**, Timothy Brandt, Taichi Uyama, Takayuki Muto, Ruobing Dong, Tomoyuki Kudo, Jun Hashimoto, Misato Fukagawa, Kevin Wagner, Julien Lozi, Jeffrey Chilcote, Taylor Tobin, Tyler Groff, Kimberly Ward-Duong, William Januszewski, Barnaby Norris, Peter Tuthill, Nienke van der Marel, Michael Sitko, Vincent Deo, Sebastien Vievard, Nemanja Jovanovic, Frantz Martinache, Nour Skaf, `arXiv:2204.00633 `_, **Nat Astron (2022) https://doi.org/10.1038/s41550-022-01634-x** ----------------------------------------------- **Dippers from TESS Full-frame Images. II. Spectroscopic Characterization of Four Young Dippers** ----------------------------------------------- Yui Kasagi, Takayuki Kotani, **Hajime Kawahara**, Tomoyuki Tajiri, Takayuki Muto, Masataka Aizawa, Michiko S. Fujii, Kohei Hattori, Kento Masuda, Munetake Momose, Ryou Ohsawa, Satoshi Takita `arXiv:2201.09459 `_, **ApJS 259 40 (2022)** ----------------------------------------------- **Polarization-based Speckle Nulling Using a Spatial Light Modulator to Generate a Wide-field Dark Hole** ----------------------------------------------- Naoshi Murakami, Kenta Yoneta, Kenya Kawai, **Hajime Kawahara**, Takayuki Kotani, Motohide Tamura, and Naoshi Baba, `IOP `_, **AJ 163 129 (2022)** ----------------------------------------------- **Autodifferentiable Spectrum Model for High-Dispersion Characterization of Exoplanets and Brown Dwarfs** ----------------------------------------------- **Hajime Kawahara**, Yui Kawashima, Kento Masuda, Ian J. M. Crossfield, Erwan Pannier, Dirk van den Bekerom `arXiv:2105.14782 `_, **ApJS 258 31 (2022)** ----------------------------------------------- **First Detection of Hydroxyl Radical Emission from an Exoplanet Atmosphere: High-dispersion Characterization of WASP-33b using Subaru/IRD** ----------------------------------------------- Stevanus K. Nugroho, **Hajime Kawahara**, Neale P. Gibson, Ernst J. W. de Mooij, Teruyuki Hirano, Takayuki Kotani, Yui Kawashima, Kento Masuda, Matteo Brogi, Jayne L. Birkby, Chris A. Watson, Motohide Tamura, Konstanze Zwintz, Hiroki Harakawa, Tomoyuki Kudo, Masayuki Kuzuhara, Klaus Hodapp, Masato Ishizuka, Shane Jacobson, Mihoko Konishi, Takashi Kurokawa, Jun Nishikawa, Masashi Omiya, Takuma Serizawa, Akitoshi Ueda, Sébastien Vievard, **ApJL 910, 9(2021)** `arXiv:2103.03094 `_, ------------------------------------ **Neutral metals in the atmosphere of HD149026b** ------------------------------------ Masato Ishizuka, **Hajime Kawahara**, Stevanus K. Nugroho, Yui Kawashima, Teruyuki Hirano, Motohide Tamura, **AJ 161, 153 (2021)**, `arXiv:2102.00211 `_, `Research highlight `_, ------------------------------------ **Dippers from the TESS Full-Frame Images I: The Results of the first 1 year data and Discovery of A Runaway dipper** ------------------------------------ Tomoyuki Tajiri, **Hajime Kawahara**, Masataka Aizawa, Michiko S. Fujii, Kohei Hattori, Yui Kasagi, Takayuki Kotani, Kento Masuda, Munetake Momose, Takayuki Muto, Ryou Ohsawa, Satoshi Takita, **ApJS, 251, 2 (2020)** `ADS `_ arXiv:2009.12830, ------------------------------------ **Bayesian Dynamic Mapping of an Exo-Earth from Photometric Variability** ------------------------------------ **Hajime Kawahara**, Kento Masuda, **ApJ 900, 48 (2020)**, `arXiv:2007.13096 `_, ------------------------------------ **Detection of Fe I Emission in the Day-side Spectrum of WASP-33b** ------------------------------------ Stevanus K. Nugroho, Neale P. Gibson, Ernst J. W. de Mooij, Miranda K. Herman, Chris A. Watson, **Hajime Kawahara**, Stephanie Merrit, **ApJL 898, L31 (2020)**, `arXiv:2007.05508 `_, ------------------------------------ **Obliquity of an Earth-like planet from frequency modulation of its direct imaged lightcurve: mock analysis from general circulation model simulation** ------------------------------------ Yuta Nakagawa, Takanori Kodama, Masaki Ishiwatari, **Hajime Kawahara**, Yasushi Suto, Yoshiyuki O. Takahashi, George L. Hashimoto, Kiyoshi Kuramoto, Kensuke Nakajima, Shin-ichi Takehiro, Yoshi-Yuki Hayashi, **ApJ 898, 95 (2020)**, `arXiv:2006.11437 `_, ------------------------------------ **Global Mapping of the Surface Composition on an Exo-Earth using Color Variability** ------------------------------------ **Hajime Kawahara**, **ApJ 894 58 (2020)**, `arXiv:2004.03931 `_, ------------------------------------ **Global Mapping of an Exo-Earth using Sparse Modeling** ------------------------------------ Masataka Aizawa, **Hajime Kawahara**, Siteng Fan, **ApJ 896, 22 (2020)** `arXiv:2004.03941 `_, ------------------------------------ **Searching for Thermal Inversion Agents in the Transmission Spectrum of MASCARA-2b/KELT-20b: Detection of Neutral Iron and Ionised Calcium H&K Lines** ------------------------------------ Stevanus K. Nugroho, Neale P. Gibson, Ernst J. W. de Mooij, Chris A. Watson, **Hajime Kawahara**, Stephanie Merritt, **MNRAS 496, 504 (2020)** `arXiv:2003.04856 `_, ------------------------------------ **Mutual Orbital Inclinations Between Cold Jupiters and Inner Super-Earths** ------------------------------------ Kento Masuda, Joshua N. Winn, **Hajime Kawahara**, **AJ 159, 38 (2020)**, `arXiv:1912.00387 `_, ------------------------------------ **Self-lensing Discovery of a 0.2M⊙ White Dwarf in an Unusually Wide Orbit Around a Sun-like Star** ------------------------------------ Kento Masuda, **Hajime Kawahara**, David W. Latham, Allyson Bieryla, Masanobu Kunitomo, Morgan MacLeod, Wako Aoki , **ApJL 881, 1 (2019)**, `arXiv:1907.07656 `_, `AAS NOVA `_, ------------------------------------ **Transiting Planets near the Snow Line from Kepler. I. Catalog** ------------------------------------ **Hajime Kawahara**, Kento Masuda, **AJ 157, 6 (2019)**, `arXiv:1904.04980 `_, ------------------------------------ **Back to "Normal" for the Disintegrating Planet Candidate KIC 12557548 b** ------------------------------------ Everett Schlawin, Teruyuki Hirano, **Hajime Kawahara**, Johanna Teske, Elizabeth Green on Benjamin V. Rackham, Jonathan Fraine, Rafia Bushra, **AJ 157, 6 (2018)** `arXiv:1810.10012 `_, `AJ `_, ------------------------------------ **A Linear and Quadratic Time-Frequency Analysis of Gravitational Waves from Core-Collapse Supernovae** ------------------------------------ **Hajime Kawahara**, Takami Kuroda, Tomoya Takiwaki, Kazuhiro Hayama, Kei Kotake, **ApJ 867, 2 (2018)** `arXiv:1810.00334 `_, `ApJ `_, ------------------------------------ **X-ray study of the double radio relic Abell 3376 with Suzaku** ------------------------------------ I. Urdampilleta, H. Akamatsu, F. Mernier, J. S. Kaastra, J. de Plaa, T. Ohashi, Y. Ishisaki, **H. Kawahara**, **A&A 618, A74 (2018)** `arXiv:1806.07817 `_, ------------------------------------ **Radial Velocity Follow-up of the Disintegrating Planet KIC 12557548b** ------------------------------------ Kento Masuda, Teruyuki Hirano, **Hajime Kawahara**, Bun'ei Sato, **RNAAS, 2, 50 (2018)** `ADS `_, ------------------------------------ **Systematic Search for Rings around Kepler Planet Candidates: Constraints on Ring Size and Occurrence Rate** ------------------------------------ Masataka Aizawa, Kento Masuda, **Hajime Kawahara**, Yasushi Suto, **AJ, 155, 206 (2018)** `arXiv:1803.09114 `_, ------------------------------------ **Discovery of Three Self-lensing Binaries from Kepler** ------------------------------------ **Hajime Kawahara**, Kento Masuda, Morgan MacLeod, David W. Latham, Allyson Bieryla, Othman Benomar, **AJ 155, 144(2018)**, `arXiv:1801.07874 `_, ------------------------------------ **High-Resolution Spectroscopic Detection of TiO and Stratosphere in the Day-side of WASP-33b** ------------------------------------ Stevanus K. Nugroho, **Hajime Kawahara**, Kento Masuda, Teruyuki Hirano, Takayuki Kotani, Akito Tajitsu, **AJ 154,221 (2017)**, `arXiv:1710.05276 `_, ------------------------------------ **Suzaku and Chandra observations of the galaxy cluster RXC J1053.7+5453 with a radio relic** ------------------------------------ Madoka Itahana, Motokazu Takizawa, Hiroki Akamatsu, Reinout J. van Weeren, **Hajime Kawahara**, Yasushi Fukazawa, Jelle S. Kaastra, Kazuhiro Nakazawa, Takaya Ohashi, Naomi Ota, Huub J. A. Röttgering, Jacco Vink, Fabio Zandanel, **PASJ 69,88 (2017)**, `arXiv:1708.07004 `_, ------------------------------------ **Towards Detection of Exoplanetary Rings Via Transit Photometry: Methodology and a Possible Candidate** ------------------------------------ Masataka Aizawa, Sho Uehara, Kento Masuda, **Hajime Kawahara**, Yasushi Suto, **AJ 153,193 (2017)**, `arXiv:1702.08252 `_, ------------------------------------ **Suzaku observations of the merging galaxy cluster Abell2255: The northeast radio relic** ------------------------------------ H. Akamatsu, M. Mizuno, N. Ota, Y.-Y. Zhang, R. J. van Weeren, **H. Kawahara**, Y. Fukazawa, J. S. Kaastra, M. Kawaharada, K. Nakazawa, T. Ohashi, H.J.A. Röttgering, M. Takizawa, J. Vink, F. Zandanel, **A&A 600, A100 (2017)**, `arXiv:1612.03058 `_, ------------------------------------ **Frequency Modulation of Directly Imaged Exoplanets: Geometric Effect as a Probe of Planetary Obliquity** ------------------------------------ **Hajime Kawahara**, **ApJ 822, 112 (2016)**, `arXiv:1603.02898 `_, ------------------------------------ **Transiting Planet Candidates Beyond the Snow Line Detected by Visual Inspection of 7557 Kepler Objects of Interest** ------------------------------------ Sho Uehara, **Hajime Kawahara**, Kento Masuda, Shin'ya Yamada, Masataka Aizawa, **ApJ, 822, 2 (2016)**, `arXiv:1602.07848 `_, ------------------------------------ **Suzaku Observations of the Galaxy Cluster 1RXS J0603.3+4214: Implications of Particle Acceleration Processes in Toothbrush Radio Relic** ------------------------------------ M. Itahana, M. Takizawa, H. Akamatsu, T. Ohashi, Y. Ishisaki, **H. Kawahara**, R. J. Van Weeren, **PASJ 67,113 (2015)**, `arXiv:1508.05845 `_, ------------------------------------ **Suzaku X-ray study of the double radio relic galaxy cluster CIZA J2242.8+5301** ------------------------------------ H. Akamatsu, R. J. van Weeren, G. A. Ogrean, **H. Kawahara**, A. Stroe, D. Sobral, M. Hoeft, H. Röttgering, M. Brüggen, J. S. Kaastra, **A&A 582, A87 (2015)** `arXiv:1507.02285 `_, ------------------------------------ **Absolute Dimensions of a Flat Hierarchical Triple System KIC 6543674 from the Kepler Photometry** ------------------------------------ Kento Masuda, Sho Uehara, **Hajime Kawahara**, **ApJL, 806, L37 (2015)**, `arXiv:1506.01891 `_, ------------------------------------ **Lifetime and Spectral Evolution of a Magma Ocean with a Steam Atmosphere: Its Detectability by Future direct Imaging** ------------------------------------ Keiko Hamano, **Hajime Kawahara**, Yutaka Abe, Masanori Onishi, George L. Hashimoto, **ApJ, 806, 216 (2015)**, `arXiv:1505.03552 `_, ------------------------------------ **Theoretical Emission Spectra of Atmospheres of Hot Rocky Super-Earths** ------------------------------------ Yuichi Ito, Masahiro Ikoma, **Hajime Kawahara**, Hiroko Nagahara, Yui Kawashima, and Taishi Nakamoto, **ApJ, 801, 144 (2014)**, `arXiv:1501.05393 `_, ------------------------------------ **Characterizing Earth-like Planets Using a Combination of High-Dispersion Spectroscopy and High-Contrast Instruments: Doppler-shifted Water and Oxygen Lines** ------------------------------------ **Hajime Kawahara**, Teruyuki Hirano `arXiv:1409.5740 `_, ------------------------------------ **Spectroscopic Coronagraphy for Planetary Radial Velocimetry of Exoplanets** ------------------------------------ **Hajime Kawahara**, Naoshi Murakami, Taro Matsuo, Takayuki Kotani, accepted for publication in ApJS, **ApJS, 212, 27 (2014)**, `arXiv:1404.5712 `_, `IOP `_ ------------------------------------ **Exploring Hot Gas at Junctions of Galaxy Filaments with Suzaku** ------------------------------------ Ikuyuki Mitsuishi, **Hajime Kawahara**, Norio Sekiya, Shin Sasaki, Thierry Sousbie, Noriko Yamasaki, **ApJ, 783, 137 (2014)**, `arXiv:1311.5042 `_, `IOP `_ -------------------------------- **Starspots - Transit Depth Relation of the Evaporating Planet Candidate KIC 12557548b** -------------------------------- **Hajime Kawahara**, Teruyuki Hirano, Kenji Kurosaki, Yuichi Ito, Masahiro Ikoma, **ApJ Letters 776, L6 (2013)**, `arXiv:1308.1585 `_, `IOP `_ -------------------------------- **Probing the extreme planetary atmosphere of WASP-12b** -------------------------------- Mark Swain, Pieter Deroo, Giovanna Tinetti, Morgan Hollis, Marcell Tessenyi, Michael Line, **Hajime Kawahara**, Yuka Fujii, Adam Showman, Sergey Yurchenko, **Icarus 225,432-445 (2013)**, `arXiv:1205.4736 `_, `Icarus `_ -------------------------------- **Validity of Hydrostatic Equilibrium in Galaxy Clusters from Cosmological Hydrodynamical Simulations** -------------------------------- Daichi Suto, **Hajime Kawahara**, Tetsu Kitayama, Shin Sasaki, Yasushi Suto, Renyue Cen, **ApJ, 767, 79 (2013)**, `arXiv:1302.5172 `_ ------------------------------------ **Systematic X-ray Analysis of Radio Relic Clusters with SUZAKU** ------------------------------------ Hiroki Akamatsu, **Hajime Kawahara**, **PASJ, 65,16 (2013)**, `ADS `_, `PASJ `_ ------------------------------------ **The Spin Effect on Planetary Radial Velocimetry of Exoplanets** ------------------------------------ **Hajime Kawahara**, **ApJ Letters 760, L13 (2012)**, `arXiv:1209.0101 `_ , `IOP `_ ------------------------------------ **Can Ground-based Telescopes Detect The Oxygen 1.27 Micron Absorption Feature as a Biomarker in Exoplanets ?** ------------------------------------ **Hajime Kawahara**, Taro Matsuo, Michihiro Takami, Yuka Fujii, Takayuki Kotani, Naoshi Murakami, Motohide Tamura, Olivier Guyon, **ApJ 758, 13 (2012)**, `arXiv:1206.0558 `_ , `IOP `_ ------------------------------------ **Mapping Earth-analogs from Photometric Variability: Spin-Orbit Tomography for Planets in Inclined Orbits** ------------------------------------ Yuka Fujii, **Hajime Kawahara**, **ApJ, 755, 101 (2012)**, `arXiv:1204.3504 `_ , `IOP `_ ------------------------------------ **Mapping Clouds and Terrain of Earth-like Planets from Photometric Variability : Demonstration with Planets in Face-on Orbits** ------------------------------------ **Hajime Kawahara**, Yuka Fujii, **ApJ Letters 739, L62 (2011)**, `arXiv:1106.0136 `_ , `IOP `_ ------------------------------------ **Colors of a Second Earth II: Effects of Clouds on Photometric Characterization of Earth-like Exoplanets** ------------------------------------ Yuka Fujii, **Hajime Kawahara**, Yasushi Suto, Satoru Fukuda, Teruyuki Nakajima, Timothy A. Livengood, Edwin L. Turner, **ApJ,738,184 (2011)**, `arXiv:1102.3625 `_ , `IOP `_ ------------------------------------ **SUZAKU Observation of a New Merging Group of Galaxies at a Filamentary Junction** ------------------------------------ **Hajime Kawahara**, Hiroshi Yoshitake, Takahiro Nishimichi, Thierry Sousbie, **ApJ Letters,727,L38 (2011)**, `ADS `_, `IOP `_ ------------------------------------ **Studying the Warm-Hot Intergalactic Medium in Emission** ------------------------------------ Yoh Takei, Eugenio Ursino, Enzo Branchini, Takaya Ohashi, **Hajime Kawahara**, Kazuhisa Mitsuda, Luigi Piro, Alessandra Corsi, Lorenzo Amati, Jan-Willem den Herder, Massimiliano Galeazzi, Jelle Kaastra, Lauro Moscardini, Fabrizio Nicastro, Frits Paerels, Mauro Roncarelli, Matteo Viel, **ApJ 734,91 (2011)**, `arXiv:1011.2116 `_ , `IOP `_ ------------------------------------ **The persistent cosmic web and its filamentary structure II: Illustrations** ------------------------------------ Thierry Sousbie,Christophe Pichon, **Hajime Kawahara**, **MNRAS,414,384 (2011)**, `ADS `_, `MNRAS `_ ------------------------------------ **Impact of Chandra calibration uncertainties on galaxy cluster temperatures: application to the Hubble Constant** ------------------------------------ Erik D. Reese, **Hajime Kawahara**, Tetsu Kitayama, Naomi Ota, Shin Sasaki, Yasushi Suto, **ApJ,721,653 (2010)**, `ADS `_, `IOP `_ ------------------------------------ **Global Mapping of Earth-like Exoplanets from Scattered Light Curves** ------------------------------------ **Hajime Kawahara**, Yuka Fujii, **ApJ,720,1333 (2010)**, `ADS `_, `IOP `_ ------------------------------------ **The axis ratio distribution of X-ray clusters observed by XMM-Newton** ------------------------------------ **Hajime Kawahara**, **ApJ,719,1926 (2010)**, `ADS `_, `IOP `_ ------------------------------------ **Colors of a Second Earth: Estimating the fractional areas of ocean, land, and vegetation of Earth-like exoplanets** ------------------------------------ Y. Fujii, **H. Kawahara**, Y. Suto, A. Taruya, S. Fukuda, T. Nakajima, E. L. Turner, **ApJ,715,866 (2010)**, `ADS `_, `IOP `_ ------------------------------------ **Inhomogeneity in Intracluster Medium and Its Cosmological Implications** ------------------------------------ **Hajime Kawahara**, **Ph.D. thesis, The University of Tokyo, (2009)** `zenodo `_ ------------------------------------ **Extracting Galaxy Cluster Gas Inhomogeneity from X-Ray Surface Brightness: A Statistical Approach and Application to Abell 3667** ------------------------------------ **Hajime Kawahara**, Erik D. Reese, Tetsu Kitayama, Shin Sasaki, Yasushi Suto, **ApJ,687,936 (2008)**, `ADS `_, `IOP `_ ------------------------------------ **Systematic Errors in the Hubble Constant Measurement from the Sunyaev-Zel'dovich Effect** ------------------------------------ **Hajime Kawahara**, Tetsu Kitayama, Shin Sasaki, Yasushi Suto, **ApJ,674,11 (2008)**, `ADS `_, `IOP `_ ------------------------------------ **X-Ray Study of Temperature and Abundance Profiles of the Cluster of Galaxies Abell 1060 with Suzaku** ------------------------------------ Kosuke Sato, Noriko Y. Yamasaki, Manabu Ishida, Yoshitaka Ishisaki, Takaya Ohashi, **Hajime Kawahara**, Takao Kitaguchi, Madoka Kawaharada, Motohide Kokubun, Kazuo Makishima, Naomi Ota, Kazuhiro Nakazawa, Takayuki Tamura, Kyoko Matsushita, Naomi Kawano, Yasushi Fukazawa, John P. Hughes, **PASJ, 59,299 (2007)**, `ADS `_ ------------------------------------ **Radial Profile and Lognormal Fluctuations of the Intracluster Medium as the Origin of Systematic Bias in Spectroscopic Temperature** ------------------------------------ **Hajime Kawahara**, Yasushi Suto, Tetsu Kitayama, Shin Sasaki, Mamoru Shimizu, Elena Rasia, Klaus Dolag, **ApJ, 659,257 (2007)**, `ADS `_, `IOP `_ ------------------------------------ **Soft X-Ray Transmission Spectroscopy of a Warm/Hot Intergalactic Medium with XEUS** ------------------------------------ **Hajime Kawahara**, Kohji Yoshikawa, Shin Sasaki, Yasushi Suto, Nobuyuki Kawai, Kazuhisa Mitsuda, Takaya Ohashi, Noriko Yamasaki, **PASJ,58,657 (2006)**, `ADS `_