T. Nagao - Ehime

T. Nagao
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T. Nagao
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Ehime
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Astrophysics of Galaxies (39)
 
Cosmology and Nongalactic Astrophysics (9)
 
Solar and Stellar Astrophysics (5)
 
High Energy Astrophysical Phenomena (5)
 
Physics - Strongly Correlated Electrons (2)
 
Physics - Materials Science (2)
 
Instrumentation and Methods for Astrophysics (2)
 
Physics - Computational Physics (2)
 
Physics - Optics (1)
 
Physics - Geophysics (1)
 
Computer Science - Neural and Evolutionary Computing (1)
 
Earth and Planetary Astrophysics (1)

Publications Authored By T. Nagao

2017Apr
Authors: H. Aihara1, N. Arimoto2, R. Armstrong3, S. Arnouts4, N. A. Bahcall5, S. Bickerton6, J. Bosch7, K. Bundy8, P. L. Capak9, J. H. H. Chan10, M. Chiba11, J. Coupon12, E. Egami13, M. Enoki14, F. Finet15, H. Fujimori16, S. Fujimoto17, H. Furusawa18, J. Furusawa19, T. Goto20, A. Goulding21, J. P. Greco22, J. E. Greene23, J. E. Gunn24, T. Hamana25, Y. Harikane26, Y. Hashimoto27, T. Hattori28, M. Hayashi29, Y. Hayashi30, K. G. Hełminiak31, R. Higuchi32, C. Hikage33, P. T. P. Ho34, B. -C. Hsieh35, K. Huang36, S. Huang37, H. Ikeda38, M. Imanishi39, A. K. Inoue40, K. Iwasawa41, I. Iwata42, A. T. Jaelani43, H. -Y. Jian44, Y. Kamata45, H. Karoji46, N. Kashikawa47, N. Katayama48, S. Kawanomoto49, I. Kayo50, J. Koda51, M. Koike52, T. Kojima53, Y. Komiyama54, A. Konno55, S. Koshida56, Y. Koyama57, H. Kusakabe58, A. Leauthaud59, C. -H. Lee60, L. Lin61, Y. -T. Lin62, R. H. Lupton63, R. Mandelbaum64, Y. Matsuoka65, E. Medezinski66, S. Mineo67, S. Miyama68, H. Miyatake69, S. Miyazaki70, R. Momose71, A. More72, S. More73, Y. Moritani74, T. J. Moriya75, T. Morokuma76, S. Mukae77, R. Murata78, H. Murayama79, T. Nagao80, F. Nakata81, M. Niida82, H. Niikura83, A. J. Nishizawa84, Y. Obuchi85, M. Oguri86, Y. Oishi87, N. Okabe88, Y. Okura89, Y. Ono90, M. Onodera91, M. Onoue92, K. Osato93, M. Ouchi94, P. A. Price95, T. -S. Pyo96, M. Sako97, S. Okamoto98, M. Sawicki99, T. Shibuya100, K. Shimasaku101, A. Shimono102, M. Shirasaki103, J. D. Silverman104, M. Simet105, J. Speagle106, D. N. Spergel107, M. A. Strauss108, Y. Sugahara109, N. Sugiyama110, Y. Suto111, S. H. Suyu112, N. Suzuki113, P. J. Tait114, T. Takata115, M. Takada116, N. Tamura117, M. M. Tanaka118, M. Tanaka119, M. Tanaka120, Y. Tanaka121, T. Terai122, Y. Terashima123, Y. Toba124, J. Toshikawa125, E. L. Turner126, T. Uchida127, H. Uchiyama128, K. Umetsu129, F. Uraguchi130, Y. Urata131, T. Usuda132, Y. Utsumi133, S. -Y. Wang134, W. -H. Wang135, K. C. Wong136, K. Yabe137, Y. Yamada138, H. Yamanoi139, N. Yasuda140, S. Yeh141, A. Yonehara142, S. Yuma143
Affiliations: 1HSC Collaboration, 2HSC Collaboration, 3HSC Collaboration, 4HSC Collaboration, 5HSC Collaboration, 6HSC Collaboration, 7HSC Collaboration, 8HSC Collaboration, 9HSC Collaboration, 10HSC Collaboration, 11HSC Collaboration, 12HSC Collaboration, 13HSC Collaboration, 14HSC Collaboration, 15HSC Collaboration, 16HSC Collaboration, 17HSC Collaboration, 18HSC Collaboration, 19HSC Collaboration, 20HSC Collaboration, 21HSC Collaboration, 22HSC Collaboration, 23HSC Collaboration, 24HSC Collaboration, 25HSC Collaboration, 26HSC Collaboration, 27HSC Collaboration, 28HSC Collaboration, 29HSC Collaboration, 30HSC Collaboration, 31HSC Collaboration, 32HSC Collaboration, 33HSC Collaboration, 34HSC Collaboration, 35HSC Collaboration, 36HSC Collaboration, 37HSC Collaboration, 38HSC Collaboration, 39HSC Collaboration, 40HSC Collaboration, 41HSC Collaboration, 42HSC Collaboration, 43HSC Collaboration, 44HSC Collaboration, 45HSC Collaboration, 46HSC Collaboration, 47HSC Collaboration, 48HSC Collaboration, 49HSC Collaboration, 50HSC Collaboration, 51HSC Collaboration, 52HSC Collaboration, 53HSC Collaboration, 54HSC Collaboration, 55HSC Collaboration, 56HSC Collaboration, 57HSC Collaboration, 58HSC Collaboration, 59HSC Collaboration, 60HSC Collaboration, 61HSC Collaboration, 62HSC Collaboration, 63HSC Collaboration, 64HSC Collaboration, 65HSC Collaboration, 66HSC Collaboration, 67HSC Collaboration, 68HSC Collaboration, 69HSC Collaboration, 70HSC Collaboration, 71HSC Collaboration, 72HSC Collaboration, 73HSC Collaboration, 74HSC Collaboration, 75HSC Collaboration, 76HSC Collaboration, 77HSC Collaboration, 78HSC Collaboration, 79HSC Collaboration, 80HSC Collaboration, 81HSC Collaboration, 82HSC Collaboration, 83HSC Collaboration, 84HSC Collaboration, 85HSC Collaboration, 86HSC Collaboration, 87HSC Collaboration, 88HSC Collaboration, 89HSC Collaboration, 90HSC Collaboration, 91HSC Collaboration, 92HSC Collaboration, 93HSC Collaboration, 94HSC Collaboration, 95HSC Collaboration, 96HSC Collaboration, 97HSC Collaboration, 98HSC Collaboration, 99HSC Collaboration, 100HSC Collaboration, 101HSC Collaboration, 102HSC Collaboration, 103HSC Collaboration, 104HSC Collaboration, 105HSC Collaboration, 106HSC Collaboration, 107HSC Collaboration, 108HSC Collaboration, 109HSC Collaboration, 110HSC Collaboration, 111HSC Collaboration, 112HSC Collaboration, 113HSC Collaboration, 114HSC Collaboration, 115HSC Collaboration, 116HSC Collaboration, 117HSC Collaboration, 118HSC Collaboration, 119HSC Collaboration, 120HSC Collaboration, 121HSC Collaboration, 122HSC Collaboration, 123HSC Collaboration, 124HSC Collaboration, 125HSC Collaboration, 126HSC Collaboration, 127HSC Collaboration, 128HSC Collaboration, 129HSC Collaboration, 130HSC Collaboration, 131HSC Collaboration, 132HSC Collaboration, 133HSC Collaboration, 134HSC Collaboration, 135HSC Collaboration, 136HSC Collaboration, 137HSC Collaboration, 138HSC Collaboration, 139HSC Collaboration, 140HSC Collaboration, 141HSC Collaboration, 142HSC Collaboration, 143HSC Collaboration

Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of the 8.2m Subaru telescope on the summit of Maunakea. A team of scientists from Japan, Taiwan and Princeton University is using HSC to carry out a 300-night multi-band imaging survey of the high-latitude sky. Read More

We have measured the clustering of galaxies around active galactic nuclei (AGN) for which single-epoch virial masses of the super-massive black hole (SMBH) are available to investigate the relation between the large scale environment of AGNs and the evolution of SMBHs. The AGN samples used in this work were derived from the Sloan Digital Sky Survey (SDSS) observations and the galaxy samples were from 250deg$^{2}$ S15b data of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). The investigated redshift range is 0. 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 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 construct a sample of X-ray bright optically faint active galactic nuclei by combining Subaru Hyper Suprime-Cam, XMM-Newton, and infrared source catalogs. 53 X-ray sources satisfying i band magnitude fainter than 23.5 mag and X-ray counts with EPIC-PN detector larger than 70 are selected from 9. 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 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

We study the heating mechansims and Ly{\alpha} escape fractions of 35 Ly{\alpha} blobs (LABs) at z = 3.1 in the SSA22 field, using the submillimeter (submm) data from the ALMA and the SCUBA-2 on the JCMT, and the radio data from the VLA. With ALMA and JCMT/SCUBA-2, we have identified dust continuum sources in 11 out of 35 LABs in the SSA22 field, with star formation rates (SFRs) of above 100Msun/yr. Read More

We investigate the star forming activity of a sample of infrared (IR)-bright dust-obscured galaxies (DOGs) that show an extreme red color in the optical and IR regime, $(i - [22])_{\rm AB} > 7.0$. Combining an IR-bright DOG sample with the flux at 22 $\mu$m $>$ 3. Read More

The convolutional neural network (CNN), which is one of the deep learning models, has seen much success in a variety of computer vision tasks. However, designing CNN architectures still requires expert knowledge and a lot of trial and error. In this paper, we attempt to automatically construct CNN architectures for an image classification task based on Cartesian genetic programming (CGP). Read More

In order to investigate the physical relationship between strong Ly-alpha absorbers (logN_HI>20.0 cm^-2) such as damped Ly-alpha absorption systems (DLAs) and young star-forming galaxies at high redshift, we have conducted narrow-band observations of Ly-alpha emitters (LAEs) in a concentrated region of strong Ly-alpha absorbers at z= 2.3, the J1230+34 field. 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 report the identification of four millimeter line emitting galaxies with the Atacama Large Milli/submillimeter Array (ALMA) in SSA22 Field (ADF22). We analyze the ALMA 1.1 mm survey data, with an effective survey area of 5 arcmin$^2$, a frequency range of 253. Read More

We report the result from observations conducted with the Atacama Large Millimeter/submillimeter Array (ALMA) to detect [CII] 158 um fine structure line emission from galaxies embedded in one of the most spectacular Lyman-alpha blobs (LABs) at z=3.1, SSA22-LAB1. Of three dusty star-forming galaxies previously discovered by ALMA 860 um dust continuum survey toward SSA22-LAB1, we detected the [CII] line from one, LAB1-ALMA3 at z=3. Read More

The nature of progenitors of the so-called super-Chandrasekhar candidate Type Ia supernovae (SC-SNe Ia) has been actively debated. Recently, Yamanaka et al. (2016) reported a near-infrared (NIR) excess for SN 2012dn, and proposed that the excess originates from an echo by circumstellar (CS) dust. 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

Outflows in active galactic nuclei (AGNs) are crucial to understand in investigating the co-evolution of supermassive black holes (SMBHs) and their host galaxies since outflows may play an important role as an AGN feedback mechanism. Based on the archival UV spectra obtained with HST and IUE, we investigate outflows in the broad-line region (BLR) in low-redshift AGNs (z < 0.4) through the detailed analysis of the velocity profile of the CIV emission line. Read More

One of the unsettled, important problems in active galactic nuclei (AGNs) is the major ionization mechanism of gas clouds in their narrow-line regions (NLRs). In order to investigate this issue, we present our $J$-band spectroscopic observations for a sample of 26 nearby Seyfert galaxies. In our study, we use the flux ratio of the following two forbidden emission lines, [Fe II]1. Read More

Recent studies have derived quasar luminosity functions (QLFs) at various redshifts. However, the faint side of the QLF at high redshifts is still too uncertain. An accurate estimate of the survey completeness is essential to derive an accurate QLF for use in studying the luminosity-dependent density evolution of the quasar population. Read More

We report precursory seismic patterns prior to the 2016 Kumamoto earthquakes, as measured by four different methods based on changes in seismicity that can be used for earthquake forecasting: the b-value method, two methods of seismic quiescence evaluation, and an analysis of seismicity density in space and time. The spatial extent of precursory patterns differs from one method to the other and ranges from local scales (typically, asperity size) to regional scales (e.g. Read More

We analyze resonant x-ray scattering (RIXS) spectra in Na$_2$IrO$_3$ on the basis of the itinerant electron picture. Employing a multi-orbital tight-binding model on a honeycomb lattice, we find that the zigzag magnetic order is the most stable with sizable energy gap in the one-electron band within the Hartree-Fock approximation. We derive the RIXS spectra, which are connected to the generalized density-density correlation function. Read More

We investigate the physical conditions of ionized gas in high-z star-forming galaxies using diagnostic diagrams based on the rest-frame optical emission lines. The sample consists of 701 galaxies with an Ha detection at $1.4\lesssim z\lesssim1. Read More

Negative feedback from active galactic nuclei (AGN) is considered a key mechanism in shaping galaxy evolution. Fast, extended outflows are frequently detected in the AGN host galaxies at all redshifts and luminosities, both in ionised and molecular gas. However, these outflows are only "potentially" able to quench star formation and we are still missing a decisive evidence of negative feedback in action. Read More

We present extensively dense observations of the super-Chandrasekhar supernova (SC SN) candidate SN 2012dn from $-11$ to $+140$ days after the date of its $B$-band maximum in the optical and near-infrared (NIR) wavelengths conducted through the OISTER ToO program. The NIR light curves and color evolutions up to 35 days after the $B$-band maximum provided an excellent match with those of another SC SN 2009dc, providing a further support to the nature of SN 2012dn as a SC SN. We found that SN 2012dn exhibited strong excesses in the NIR wavelengths from $30$ days after the $B$-band maximum. Read More

Many astronomical objects are surrounded by dusty environments. In such dusty objects, multiple scattering processes of photons by circumstellar (CS) dust grains can effectively alter extinction properties. In this paper, we systematically investigate effects of multiple scattering on extinction laws for steady-emission sources surrounded by the dusty CS medium, using a radiation transfer simulation based on the Monte Carlo technique. Read More

We present a new method to effectively select objects which may be low-mass active black holes (BHs) at galaxy centers using high-cadence optical imaging data, and our first spectroscopic identification of an active 2.7x10^6 Msun BH at z=0.164. Read More

We aim to search for hyperliminous infrared (IR) galaxies (HyLIRGs) with IR luminosity $L_{{\rm IR}}$ $>$ 10$^{13}$ $L_{\odot}$ by applying the selection method of Dust Obscured Galaxies (DOGs). They are spatially rare but could correspond to a maximum phase of cosmic star formation and/or active galactic nucleus (AGN) activity, hence they are a crucial population for understanding the star formation and mass assembly history of galaxies. Combining the optical and IR catalogs obtained from Sloan Digital Sky Survey (SDSS) and Wide-field Infrared Survey Explorer (WISE), we performed the extensive HyLIRGs survey; we selected 5,311 IR-bright DOGs with $i$ -- [22] $>$ 7. Read More

We present the first results from MMT and Keck spectroscopy for a large sample of $0.1\leq z\leq1$ emission-line galaxies selected from our narrow-band imaging in the Subaru Deep Field. We measured the weak [OIII]$\lambda$4363 emission line for 164 galaxies (66 with at least 3$\sigma$ detections, and 98 with significant upper limits). Read More

We investigate morphological properties of 61 Lyman-alpha emitters (LAEs) at z = 4.86 identified in the COSMOS field, based on Hubble Space Telescope Advanced Camera for Surveys (ACS) imaging data in the F814W-band. Out of the 61 LAEs, we find the ACS counterparts for the 54 LAEs. Read More

Chemical composition is the primary factor that determines the electronic band structure and thus also influences the optical properties of plasmonic ceramics including nitrides and oxides. In this work, the optical and plasmonic properties of TiN, ZrN and their hypothetical intermediate alloys Ti1-xZrxN (x= 0, 0.25, 0. Read More

The ability to accurately derive black hole (BH) masses at progressively higher redshifts and over a wide range of continuum luminosities has become indispensable in the era of large-area extragalactic spectroscopic surveys. In this paper we present an extension of existing comparisons between rest-frame UV and optical virial BH mass estimators to intermediate redshifts and luminosities comparable to the local H$\beta$ reverberation mapped active galactic nuclei (AGN). We focus on the MgII, CIV, and CIII] broad emission lines and compare them to both H$\alpha$ and H$\beta$. Read More

The main aim of this study is to scrutinize promising plasmonic materials by understanding their electronic structure and correlating them to the optical properties of selected refractory materials. For this purpose, the electronic and optical properties of the conductive ceramics TiC, ZrC, HfC, TaC, WC, TiN, ZrN, HfN, TaN, and WN are studied systematically by means of first-principles density functional theory. A full ab initio procedure to calculate plasma frequency from the electronic band structure is discussed. Read More

2015Oct
Affiliations: 1GUAS/Subaru/NAOJ, 2Subaru/NAOJ/GUAS, 3Subaru/NAOJ/GUAS, 4University of Tokyo, 5Sapporo Medical University, 6Kyoto Sangyo University, 7University of Tokyo, 8JAXA, 9Ehime University, 10Kure National College of Technology, 11Kyoto University

We present the results of new infrared spectroscopic observations of 37 quasars at z~3, selected based on the optical r'-band magnitude and the availability of nearby bright stars for future imaging follow-up with Adaptive Optics system. The supermassive black hole (SMBH) masses (M_BH) were successfully estimated in 28 out of 37 observed objects from the combination of the H_beta emission linewidth and continuum luminosity at rest-frame 5100A. Comparing these results with those from previous studies of quasars with similar redshift, our sample exhibited slightly lower (~ -0. Read More

We present both the observations and the data reduction procedures of the Subaru COSMOS 20 project that is an optical imaging survey of the HST COSMOS field, carried out by using Suprime-Cam on the Subaru Telescope with the following 20 optical filters: 6 broad-band (B, g', V, r', i', and z'), 2 narrow-band (NB711 and NB816), and 12 intermediate-band filters (IA427, IA464, IA484, IA505, IA527, IA574, IA624, IA679, IA709, IA738, IA767, and IA827). A part of this project is described in Taniguchi et al. (2007) and Capak et al. Read More

We study the collective excitations of Na$_2$IrO$_3$ in an itinerant electron approach. We consider a multi-orbital tight-binding model with the electron transfer between the Ir $5d$ states mediated via oxygen $2p$ states and the direct $d$-$d$ transfer on a honeycomb lattice. The one-electron energy as well as the ground state energy are investigated within the Hartree-Fock approximation. Read More

We study the ionization and kinematics of the ionized gas in the nuclear region of the barred Seyfert 2 galaxy NGC~5643 using MUSE integral field observations in the framework of the MAGNUM (Measuring Active Galactic Nuclei Under MUSE Microscope) survey. The data were used to identify regions with different ionization conditions and to map the gas density and the dust extinction. We find evidence for a double sided ionization cone, possibly collimated by a dusty structure surrounding the nucleus. Read More

In order to investigate the origin of quasars, we estimate the bias factor for low-luminosity quasars at high redshift for the first time. In this study, we use the two-point angular cross-correlation function (CCF) for both low-luminosity quasars at $-24Read More

We report a discovery of 6 massive galaxies with both extremely large Lya equivalent width and evolved stellar population at z ~ 3. These MAssive Extremely STrong Lya emitting Objects (MAESTLOs) have been discovered in our large-volume systematic survey for strong Lya emitters (LAEs) with twelve optical intermediate-band data taken with Subaru/Suprime-Cam in the COSMOS field. Based on the SED fitting analysis for these LAEs, it is found that these MAESTLOs have (1) large rest-frame equivalent width of EW_0(Lya) ~ 100--300 A, (2) M_star ~ 10^10. Read More

The aim of this paper is to test the basic model of negative AGN feedback. According to this model, once the central black hole accretes at the Eddington limit and reaches a certain critical mass, AGN driven outflows blow out gas, suppressing star formation in the host galaxy and self-regulating black hole growth. We consider a sample of 224 quasars selected from the SDSS at z<1 observed in the infrared band by Herschel. Read More

AGN-driven outflows are invoked by galaxy evolutionary models to quench star formation and to explain the origin of the relations observed locally between super massive black holes and their host galaxies. This work aims to detect the presence of extended ionised outflows in luminous quasars where we expect the maximum activity both in star formation and in black hole accretion. Currently, there are only a few studies based on spatially resolved observations of outflows at high redshift, $z>2$. Read More

We present the photometric properties of a sample of infrared (IR) bright dust obscured galaxies (DOGs). Combining wide and deep optical images obtained with the Hyper Suprime-Cam (HSC) on the Subaru Telescope and all-sky mid-IR (MIR) images taken with Wide-Field Infrared Survey Explorer (WISE), we discovered 48 DOGs with $i - K_\mathrm{s} > 1.2$ and $i - [22] > 7. Read More