Masayuki Tanaka - NAOJ

Masayuki Tanaka
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Masayuki Tanaka
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NAOJ
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Astrophysics of Galaxies (35)
 
Cosmology and Nongalactic Astrophysics (35)
 
High Energy Astrophysical Phenomena (3)
 
Instrumentation and Methods for Astrophysics (3)
 
Earth and Planetary Astrophysics (2)
 
Solar and Stellar Astrophysics (1)

Publications Authored By Masayuki Tanaka

We present the results from a search for new Milky Way (MW) satellites from the first two years of data from the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP) $\sim 300$~deg$^2$ and report the discovery of an ultra-faint dwarf galaxy in Cetus. This is the second ultra-faint dwarf we have discovered after Virgo~I reported in our previous paper. This new satellite, Cetus~III, has been identified as a statistically significant (10. Read More

We present initial results from the Subaru Strategic Program (SSP) with Hyper Suprime-Cam (HSC) on a comprehensive survey of emission line galaxies at $z<1.5$. In the first data release of the HSC-SSP, two narrowband data (NB816 and NB921) down to 25. Read More

We present the environmental dependence of colour, stellar mass, and star formation (SF) activity in H-alpha-selected galaxies along the huge cosmic web at z=0.4 hosting twin clusters in DEEP2-3 field, discovered by Subaru Strategic Programme of Hyper Suprime-Cam (HSC SSP). By combining photo-z selected galaxies and H-alpha emitters selected with broad-band and narrow-band data of the recent internal data release of HSC SSP (DR1), we confirm that galaxies in higher-density environments or galaxies in the cluster central regions show redder colours. Read More

Photometric redshifts are a key component of many science objectives in the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). In this paper, we describe and compare the codes used to compute photometric redshifts for HSC-SSP, how we calibrate them, and the typical accuracy we achieve with HSC five-band photometry (grizy). We introduce a new point estimator based on an improved loss function and demonstrate that it works better than other commonly used estimators. Read More

We study the UV luminosity functions (LFs) at $z\sim 4$, $5$, $6,$ and $7$ based on the deep large-area optical images taken by the Hyper Suprime-Cam (HSC) Subaru strategic program (SSP). On the 100 deg$^2$ sky of the HSC SSP data available to date, we make enormous samples consisting of a total of 579,555 dropout candidates at $z\sim 4-7$ by the standard color selection technique, 348 out of which are spectroscopically confirmed by our follow-up spectroscopy and the other studies. We obtain the UV LFs at $z \sim 4-7$ that span a very wide UV luminosity range of $\sim 0. Read More

We investigate the galaxy overdensity around <2 pMpc-scale quasar pairs at high (z>3) and low (z~1) redshift based on the unprecedentedly wide and deep optical survey of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). Using the first-year survey data covering effectively ~121 deg2 in full-color and depth, we find two luminous pairs at z~3.6 and 3. Read More

2017Apr
Affiliations: 1SOKENDAI, Japan, 2NAOJ, Japan, 3SOKENDAI, Japan, 4Observatorio Nacional, Brazil, 5Johns Hopkins University, USA, 6NAOJ, Japan, 7NAOJ, Japan, 8SOKENDAI, Japan, 9SOKENDAI, Japan, 10NAOJ, Japan, 11Tohoku University, Japan, 12University of Geneva, Switzerland, 13Institute for Cosmic Ray Research, The University of Tokyo, Japan, 14SOKENDAI, Japan, 15SOKENDAI, Japan, 16SOKENDAI, Japan, 17NAOJ, USA, 18ASSIA, Taiwan, 19SOKENDAI, Japan, 20Ehime University, Japan, 21Nagoya University, Japan, 22Institute for Cosmic Ray Research, The University of Tokyo, Japan, 23Institute for Cosmic Ray Research, The University of Tokyo, Japan, 24Princeton University, USA, 25ASSIA, Taiwan

We present the cross-correlation between 151 luminous quasars ($M_{ \mathrm{UV}} < -26$) and 179 protocluster candidates at $z \sim 3.8$, extracted from the Wide imaging survey ($ \sim 121~ $deg$^2$) performed with a part of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). We find that only two out of 151 quasars reside in regions that are more overdense compared to the average field at $ > 4 \sigma $. Read More

We report the discovery of a diffuse stellar cloud with an angular extent $\gtrsim30^{\prime\prime}$, which we term "Sumo Puff", in data from the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). While we do not have a redshift for this object, it is in close angular proximity to a post-merger galaxy at redshift $z=0.0431$ and is projected within a few virial radii (assuming similar redshifts) of two other ${\sim}L_\star$ galaxies, which we use to bracket a potential redshift range of $0. Read More

We utilize the HSC CAMIRA cluster catalog and the photo-$z$ galaxy catalog constructed in the HSC wide field (S16A), covering $\sim$ 174 deg$^{2}$, to study the star formation activity of galaxies in different environments over 0.2 $<$ $z$ $<$ 1.1. Read More

We present the luminosity function of z=4 quasars based on the Hyper Suprime-Cam Subaru Strategic Program Wide layer imaging data in the g, r, i, z, and y bands covering 339.8 deg^2. From stellar objects, 1666 z~4 quasar candidates are selected by the g-dropout selection down to i=24. Read More

2017Apr
Affiliations: 1Kavli IPMU, The University of Tokyo, 2National Taiwan University, 3NAOC, 4Kavli IPMU, The University of Tokyo, 5Kavli IPMU, The University of Tokyo, 6ASIAA, 7ASIAA, 8Subaru Telescope, 9University of Geneva, 10Kyoto Sangyo University, 11NOAO, 12Tohoku University, 13NAOJ, 14NAOJ, 15NAOJ

The Hyper Suprime-Cam Subaru Strategic Program (HSC SSP) is an excellent survey for the search for strong lenses, thanks to its area, image quality and depth. We use three different methods to look for lenses among 43,000 luminous red galaxies from the Baryon Oscillation Spectroscopic Survey (BOSS) sample with photometry from the S16A internal data release of the HSC SSP. The first method is a newly developed algorithm, named YATTALENS, which looks for arc-like features around massive galaxies and then estimates the likelihood of an object being a lens by performing a lens model fit. Read More

2017Feb
Authors: Hiroaki Aihara, Robert Armstrong, Steven Bickerton, James Bosch, Jean Coupon, Hisanori Furusawa, Yusuke Hayashi, Hiroyuki Ikeda, Yukiko Kamata, Hiroshi Karoji, Satoshi Kawanomoto, Michitaro Koike, Yutaka Komiyama, Robert H. Lupton, Sogo Mineo, Hironao Miyatake, Satoshi Miyazaki, Tomoki Morokuma, Yoshiyuki Obuchi, Yukie Oishi, Yuki Okura, Paul A. Price, Tadafumi Takata, Manobu M. Tanaka, Masayuki Tanaka, Yoko Tanaka, Tomohisa Uchida, Fumihiro Uraguchi, Yousuke Utsumi, Shiang-Yu Wang, Yoshihiko Yamada, Hitomi Yamanoi, Naoki Yasuda, Nobuo Arimoto, Masashi Chiba, Francois Finet, Hiroki Fujimori, Seiji Fujimoto, Junko Furusawa, Tomotsugu Goto, Andy Goulding, James E. Gunn, Yuichi Harikane, Takashi Hattori, Masao Hayashi, Krzysztof G. Helminiak, Ryo Higuchi, Chiaki Hikage, Paul T. P. Ho, Bau-Ching Hsieh, Kuiyun Huang, Song Huang, Masatoshi Imanishi, Ikuru Iwata, Anton T. Jaelani, Hung-Yu Jian, Nobunari Kashikawa, Nobuhiko Katayama, Takashi Kojima, Akira Konno, Shintaro Koshida, Alexie Leauthaud, C. -H. Lee, Lihwai Lin, Yen-Ting Lin, Rachel Mandelbaum, Yoshiki Matsuoka, Elinor Medezinski, Shoken Miyama, Rieko Momose, Anupreeta More, Surhud More, Shiro Mukae, Ryoma Murata, Hitoshi Murayama, Tohru Nagao, Fumiaki Nakata, Hiroko Niikura, Atsushi J. Nishizawa, Masamune Oguri, Nobuhiro Okabe, Yoshiaki Ono, Masato Onodera, Masafusa Onoue, Masami Ouchi, Tae-Soo Pyo, Takatoshi Shibuya, Kazuhiro Shimasaku, Melanie Simet, Joshua Speagle, David N. Spergel, Michael A. Strauss, Yuma Sugahara, Naoshi Sugiyama, Yasushi Suto, Nao Suzuki, Philip J. Tait, Masahiro Takada, Tsuyoshi Terai, Yoshiki Toba, Edwin L. Turner, Hisakazu Uchiyama, Keiichi Umetsu, Yuji Urata, Tomonori Usuda, Sherry Yeh, Suraphong Yuma

The Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) is a three-layered imaging survey aimed at addressing some of the most outstanding questions in astronomy today, including the nature of dark matter and dark energy. The survey has been awarded 300 nights of observing time at the Subaru Telescope. The survey started in March 2014. Read More

We present an optically-selected cluster catalog from the Hyper Suprime-Cam (HSC) Subaru Strategic Program. The HSC images are sufficiently deep to detect cluster member galaxies down to $M_*\sim 10^{10.2}M_\odot$ even at $z\sim 1$, allowing a reliable cluster detection at such high redshifts. Read More

We present the results of clustering analyses of Lyman break galaxies (LBGs) at $z\sim3$, $4$, and $5$ using the final data release of the Canada--France--Hawaii Telescope Legacy Survey (CFHTLS). Deep- and wide-field images of the CFHTLS Deep Survey enable us to obtain sufficiently accurate two-point angular correlation functions to apply a halo occupation distribution analysis. Mean halo masses, calculated as $\langle M_{h} \rangle=10^{11. Read More

We present measurements of the clustering properties of a sample of infrared (IR) bright dust-obscured galaxies (DOGs). Combining 125 deg$^2$ of wide and deep optical images obtained with the Hyper Suprime-Cam on the Subaru Telescope and all-sky mid-IR (MIR) images taken with Wide-Field Infrared Survey Explorer, we have discovered 4,367 IR-bright DOGs with $(i - [22])_{\rm AB}$ $>$ 7.0 and flux density at 22 $\mu$m $>$ 1. Read More

We report the discovery of a new ultra-faint dwarf satellite companion of the Milky Way based on the early survey data from the Hyper Suprime-Cam Subaru Strategic Program. This new satellite, Virgo I, which is located in the constellation of Virgo, has been identified as a statistically significant (5.5 sigma) spatial overdensity of star-like objects with a well-defined main sequence and red giant branch in their color-magnitude diagram. Read More

We report the serendipitous discovery of HSC J142449-005322, a double source plane lens system in the Hyper Suprime-Cam Subaru Strategic Program. We dub the system Eye of Horus. The lens galaxy is a very massive early-type galaxy with stellar mass of ~7x10^11 Msun located at z_L=0. Read More

We present an overview of the "KIFF" project, which provides ultra-deep Ks-band imaging of all six of the Hubble Frontier Fields clusters Abell 2744, MACS-0416, Abell S1063, Abell 370, MACS-0717 and MACS-1149. All of these fields have recently been observed with large allocations of Directors' Discretionary Time with the HST and Spitzer telescopes covering 0.4 < lambda < 1. Read More

We present the discovery of three protoclusters at $z\sim3\mathrm{-}4$ with spectroscopic confirmation in the Canada-France-Hawaii Telescope (CFHT) Legacy Survey Deep Fields. In these fields, we investigate the large-scale projected sky distribution of $z\sim3\mathrm{-}6$ Lyman break galaxies and identify 21 protocluster candidates from regions that are overdense at more than $4\sigma$ overdensity significance. Based on cosmological simulations, it is expected that more than $76\%$ of these candidates will evolve into a galaxy cluster of at least a halo mass of $10^{14}\,\mathrm{M_\odot}$ at $z=0$. Read More

We study the distribution and evolution of the stellar mass and the star formation rate (SFR) of the brightest group galaxies (BGGs) over $ 0.04Read More

We present a weak-lensing analysis for the merging galaxy cluster, CIZA J2242.8+5301, hosting double radio relics, using three-band Subaru/Suprime-Cam imaging ($Br'z'$). Since the lifetime of dark matter halos colliding into clusters is longer than that of X-ray emitting gas halos, weak-lensing analysis is a powerful method to constrain a merger dynamics. Read More

We study the environmental dependence of the strength of polycyclic aromatic hydrocarbon (PAH) emission by AKARI observations of RX J0152.7-1357, a galaxy cluster at z=0.84. Read More

2015May
Authors: Warren Skidmore, Ian Dell'Antonio, Misato Fukugawa, Aruna Goswami, Lei Hao, David Jewitt, Greg Laughlin, Charles Steidel, Paul Hickson, Luc Simard, Matthias Schöck, Tommaso Treu, Judith Cohen, G. C. Anupama, Mark Dickinson, Fiona Harrison, Tadayuki Kodama, Jessica R. Lu, Bruce Macintosh, Matt Malkan, Shude Mao, Norio Narita, Tomohiko Sekiguchi, Annapurni Subramaniam, Masaomi Tanaka, Feng Tian, Michael A'Hearn, Masayuki Akiyama, Babar Ali, Wako Aoki, Manjari Bagchi, Aaron Barth, Varun Bhalerao, Marusa Bradac, James Bullock, Adam J. Burgasser, Scott Chapman, Ranga-Ram Chary, Masashi Chiba, Michael Cooper, Asantha Cooray, Ian Crossfield, Thayne Currie, Mousumi Das, G. C. Dewangan, Richard de Grijs, Tuan Do, Subo Dong, Jarah Evslin, Taotao Fang, Xuan Fang, Christopher Fassnacht, Leigh Fletcher, Eric Gaidos, Roy Gal, Andrea Ghez, Mauro Giavalisco, Carol A. Grady, Thomas Greathouse, Rupjyoti Gogoi, Puragra Guhathakurta, Luis Ho, Priya Hasan, Gregory J. Herczeg, Mitsuhiko Honda, Masa Imanishi, Hanae Inami, Masanori Iye, Jason Kalirai, U. S. Kamath, Stephen Kane, Nobunari Kashikawa, Mansi Kasliwal, Vishal Kasliwal, Evan Kirby, Quinn M. Konopacky, Sebastien Lepine, Di Li, Jianyang Li, Junjun Liu, Michael C. Liu, Enrigue Lopez-Rodriguez, Jennifer Lotz, Philip Lubin, Lucas Macri, Keiichi Maeda, Franck Marchis, Christian Marois, Alan Marscher, Crystal Martin, Taro Matsuo, Claire Max, Alan McConnachie, Stacy McGough, Carl Melis, Leo Meyer, Michael Mumma, Takayuki Muto, Tohru Nagao, Joan R. Najita, Julio Navarro, Michael Pierce, Jason X. Prochaska, Masamune Oguri, Devendra K. Ojha, Yoshiko K. Okamoto, Glenn Orton, Angel Otarola, Masami Ouchi, Chris Packham, Deborah L. Padgett, Shashi Bhushan Pandey, Catherine Pilachowsky, Klaus M. Pontoppidan, Joel Primack, Shalima Puthiyaveettil, Enrico Ramirez-Ruiz, Naveen Reddy, Michael Rich, Matthew J. Richter, James Schombert, Anjan Ananda Sen, Jianrong Shi, Kartik Sheth, R. Srianand, Jonathan C. Tan, Masayuki Tanaka, Angelle Tanner, Nozomu Tominaga, David Tytler, Vivian U, Lingzhi Wang, Xiaofeng Wang, Yiping Wang, Gillian Wilson, Shelley Wright, Chao Wu, Xufeng Wu, Renxin Xu, Toru Yamada, Bin Yang, Gongbo Zhao, Hongsheng Zhao

The TMT Detailed Science Case describes the transformational science that the Thirty Meter Telescope will enable. Planned to begin science operations in 2024, TMT will open up opportunities for revolutionary discoveries in essentially every field of astronomy, astrophysics and cosmology, seeing much fainter objects much more clearly than existing telescopes. Per this capability, TMT's science agenda fills all of space and time, from nearby comets and asteroids, to exoplanets, to the most distant galaxies, and all the way back to the very first sources of light in the Universe. Read More

We present properties of moderately massive clusters of galaxies detected by the newly developed Hyper Suprime-Cam on the Subaru telescope using weak gravitational lensing. Eight peaks exceeding a S/N ratio of 4.5 are identified on the convergence S/N map of a 2. Read More

We report on the weak lensing detection of a filament between two galaxy clusters at $z=0.55$, CL0015.9+1609 and RX J0018. Read More

We present a proof-of-concept analysis of photometric redshifts with Bayesian priors on physical properties of galaxies. This concept is particularly suited for upcoming/on-going large imaging surveys, in which only several broad-band filters are available and it is hard to break some of the degeneracies in the multi-color space. We construct model templates of galaxies using a stellar population synthesis code and apply Bayesian priors on physical properties such as stellar mass and star formation rate. Read More

We present the data release of the Gemini-South GMOS spectroscopy in the fields of 11 galaxy groups at $0.8Read More

We use Chandra data to study the incidence and properties of Active Galactic Nuclei (AGN) in 16 intermediate redshift ($0.5 < z < 1.1$) X-ray-selected galaxy groups in the Chandra Deep Field-South. Read More

Objects of known brightness, like Type Ia supernovae (SNIa), can be used to measure distances. If a massive object warps spacetime to form multiple images of a background SNIa, a direct test of cosmic expansion is also possible. However, these lensing events must first be distinguished from other rare phenomena. Read More

2014Feb
Affiliations: 1Osaka Sangyo University, 2The University of Tokyo, 3NAOJ Subaru, 4NAOJ Mitaka

We present an updated version of the so-called Madau model for the attenuation by the intergalactic neutral hydrogen against the radiation from distant objects. First, we derive a distribution function of the intergalactic absorbers from the latest observational statistics of the Ly$\alpha$ forest, Lyman limit systems, and damped Ly$\alpha$ systems. The distribution function excellently reproduces the observed redshift evolutions of the Ly$\alpha$ depression and of the mean-free-path of the Lyman continuum simultaneously. Read More

The galaxy cluster CLG0218.3-0510 at z=1.62 is one of the most distant galaxy clusters known, with a rich muti-wavelength data set that confirms a mature galaxy population already in place. Read More

The scaling between X-ray observables and mass for galaxy clusters and groups is instrumental for cluster based cosmology and an important probe for the thermodynamics of the intracluster gas. We calibrate a scaling relation between the weak lensing mass and X-ray spectroscopic temperature for 10 galaxy groups in the COSMOS field, combined with 55 higher mass clusters from the literature. The COSMOS data includes HST imaging and redshift measurements of 46 source galaxies per square arcmin, enabling us to perform unique weak lensing measurements of low mass systems. Read More

We present improved constraints on the formation time scale of massive cluster galaxies based on rest-frame optical spectra of galaxies in a forming cluster located at z=2.16. The spectra are obtained with MOIRCS on the Subaru telescope with an integration time of ~7 hours. Read More

Recently, Chornock and co-workers announced the Pan-STARRS discovery of a transient source reaching an apparent peak luminosity of ~4x10^44 erg s^-1. We show that the spectra of this transient source are well fit by normal Type Ia supernova (SNIa) templates. The multi-band colors and light-curve shapes are also consistent with normal SNeIa at the spectroscopically determined redshift of z=1. Read More

We present a panoramic narrow-band study of H-alpha emitters in the field of the z=2.16 proto-cluster around PKS1138-262 using MOIRCS on the Subaru Telescope. We find 83 H-alpha emitters down to a SFR(Ha)~10Msun/yr across a ~7'x7' region centered on the radio galaxy, and identify ~10-Mpc scale filaments of emitters running across this region. Read More

(Abridged) We report the discovery of an X-ray group of galaxies located at a high redshift of z=1.61 in the Chandra Deep Field South. The group is first identified as an extended X-ray source. Read More

2012Jul
Authors: Kyle S. Dawson, David J. Schlegel, Christopher P. Ahn, Scott F. Anderson, Éric Aubourg, Stephen Bailey, Robert H. Barkhouser, Julian E. Bautista, Alessandra Beifiori, Andreas A. Berlind, Vaishali Bhardwaj, Dmitry Bizyaev, Cullen H. Blake, Michael R. Blanton, Michael Blomqvist, Adam S. Bolton, Arnaud Borde, Jo Bovy, W. N. Brandt, Howard Brewington, Jon Brinkmann, Peter J. Brown, Joel R. Brownstein, Kevin Bundy, N. G. Busca, William Carithers, Aurelio R. Carnero, Michael A. Carr, Yanmei Chen, Johan Comparat, Natalia Connolly, Frances Cope, Rupert A. C. Croft, Antonio J. Cuesta, Luiz N. da Costa, James R. A. Davenport, Timothée Delubac, Roland de Putter, Saurav Dhital, Anne Ealet, Garrett L. Ebelke, Daniel J. Eisenstein, S. Escoffier, Xiaohui Fan, N. Filiz Ak, Hayley Finley, Andreu Font-Ribera, R. Génova-Santos, James E. Gunn, Hong Guo, Daryl Haggard, Patrick B. Hall, Jean-Christophe Hamilton, Ben Harris, David W. Harris, Shirley Ho, David W. Hogg, Diana Holder, Klaus Honscheid, Joe Huehnerhoff, Beatrice Jordan, Wendell P. Jordan, Guinevere Kauffmann, Eyal A. Kazin, David Kirkby, Mark A. Klaene, Jean-Paul Kneib, Jean-Marc Le Goff, Khee-Gan Lee, Daniel C. Long, Craig P. Loomis, Britt Lundgren, Robert H. Lupton, Marcio A. G. Maia, Martin Makler, Elena Malanushenko, Viktor Malanushenko, Rachel Mandelbaum, Marc Manera, Claudia Maraston, Daniel Margala, Karen L. Masters, Cameron K. McBride, Patrick McDonald, Ian D. McGreer, Richard McMahon, Olga Mena, Jordi Miralda-Escudé, Antonio D. Montero-Dorta, Francesco Montesano, Demitri Muna, Adam D. Myers, Tracy Naugle, Robert C. Nichol, Pasquier Noterdaeme, Sebastián E. Nuza, Matthew D. Olmstead, Audrey Oravetz, Daniel J. Oravetz, Russell Owen, Nikhil Padmanabhan, Nathalie Palanque-Delabrouille, Kaike Pan, John K. Parejko, Isabelle Pâris, Will J. Percival, Ismael Pérez-Fournon, Ignasi Pérez-Ràfols, Patrick Petitjean, Robert Pfaffenberger, Janine Pforr, Matthew M. Pieri, Francisco Prada, Adrian M. Price-Whelan, M. Jordan Raddick, Rafael Rebolo, James Rich, Gordon T. Richards, Constance M. Rockosi, Natalie A. Roe, Ashley J. Ross, Nicholas P. Ross, Graziano Rossi, J. A. Rubiño-Martin, Lado Samushia, Ariel G. Sánchez, Conor Sayres, Sarah J. Schmidt, Donald P. Schneider, C. G. Scóccola, Hee-Jong Seo, Alaina Shelden, Erin Sheldon, Yue Shen, Yiping Shu, Anže Slosar, Stephen A. Smee, Stephanie A. Snedden, Fritz Stauffer, Oliver Steele, Michael A. Strauss, Alina Streblyanska, Nao Suzuki, Molly E. C. Swanson, Tomer Tal, Masayuki Tanaka, Daniel Thomas, Jeremy L. Tinker, Rita Tojeiro, Christy A. Tremonti, M. Vargas Magana, Licia Verde, Matteo Viel, David A. Wake, Mike Watson, Benjamin A. Weaver, David H. Weinberg, Benjamin J. Weiner, Andrew A. West, Martin White, W. M. Wood-Vasey, Christophe Yeche, Idit Zehavi, Gong-Bo Zhao, Zheng Zheng

The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large scale structure. BOSS uses 1.5 million luminous galaxies as faint as i=19. Read More

X-ray selected galaxy group samples are usually generated by searching for extended X- ray sources that reflect the thermal radiation of the intragroup medium. On the other hand, large radio galaxies that regularly occupy galaxy groups also emit in the X-ray window, and their contribution to X-ray selected group samples is still not well understood. In order to investigate their relative importance, we have carried out a systematic search for non-thermal extended X-ray sources in the COSMOS field. Read More

We present a panoramic narrow-band imaging survey of [OII] emitters in and around the ClG J0218.3-0510 cluster at z=1.62 with Suprime-Cam on Subaru telescope. Read More