研究者業績

松原 英雄

マツハラ ヒデオ  (Hideo Matsuhara)

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 宇宙物理学研究系 教授
総合研究大学院大学(総研大) 物理科学研究科 宇宙科学専攻 教授
東京工業大学 大学院理工学研究科 基礎物理学専攻 教授
学位
理学博士(京都大学)

J-GLOBAL ID
200901048367768240
researchmap会員ID
5000019049

外部リンク

論文

 213
  • S. Koyama, H. Matsuhara
    Publications of The Korean Astronomical Society 32(1) 309-311 2017年  査読有り責任著者
  • Yoshiki Toba, Tohru Nagao, Masaru Kajisawa, Taira Oogi, Masayuki Akiyama, Hiroyuki Ikeda, Jean Coupon, Michael A. Strauss, Wei-Hao Wang, Masayuki Tanaka, Mana Niida, Masatoshi Imanishi, Chien-Hsiu Lee, Hideo Matsuhara, Yoshiki Matsuoka, Masafusa Onoue, Yuichi Terashima, Yoshihiro Ueda, Yuichi Harikane, Yutaka Komiyama, Satoshi Miyazaki, Akatoki Noboriguchi, Tomonori Usuda
    The Astrophysical Journal 835(1) 36-36 2016年12月4日  
    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 $>$ 1.0 mJy. We calculate the angular autocorrelation function (ACF) for a uniform subsample of 1411 DOGs with 3.0 mJy $<$ flux (22 $mu$m) $<$ 5.0 mJy and $i_{\rm AB}$ $<$ 24.0. The ACF of our DOG subsample is well-fit with a single power-law, $\omega (\theta)$ = (0.010 $\pm$ 0.003) $\theta^{-0.9}$, where $\theta$ in degrees. The correlation amplitude of IR-bright DOGs is larger than that of IR-faint DOGs, which reflects a flux-dependence of the DOG clustering, as suggested by Brodwin et al. (2008). We assume that the redshift distribution for our DOG sample is Gaussian, and consider 2 cases: (1) the redshift distribution is the same as IR-faint DOGs with flux at 22 $\mu$m $<$ 1.0 mJy, mean and sigma $z$ = 1.99 $\pm$ 0.45, and (2) $z$ = 1.19 $\pm$ 0.30, as inferred from their photometric redshifts. The inferred correlation length of IR-bright DOGs is $r_0$ = 12.0 $\pm$ 2.0 and 10.3 $\pm$ 1.7 $h^{-1}$ Mpc, respectively. IR-bright DOGs reside in massive dark matter halos with a mass of $\log [\langle M_{\mathrm{h } } \rangle / (h^{-1} M_{\odot})]$ = 13.57$_{-0.55}^{+0.50}$ and 13.65$_{-0.52}^{+0.45}$ in the two cases, respectively.
  • H. Ogawa, T. Nakagawa, H. Matsuhara, K. Shinozaki, K. Goto, N. Isobe, M. Kawada, T. Mizutani, Y. Sato, H. Sugita, S. Takeuchi, T. Yamawaki, H. Shibai
    Proceedings of SPIE - The International Society for Optical Engineering 9904 2016年  
    We present the new design of the cryogenic system of the next-generation infrared astronomy mission SPICA under the new framework. The new design employs the V-groove design for radiators, making the best use of the Planck heritage. The new design is based on the ESA-JAXA CDF study (NG-CryoIRTel, CDF-152(A)) with a 2 m telescope, and we modified the CDF design to accommodate the 2.5 m telescope to meet the science requirements of SPICA. The basic design concept of the SPICA cryogenic system is to cool the Science Instrument Assembly (SIA, which is the combination of the telescope and focal-plane instruments) below 8K by the combination of the radiative cooling system and mechanical cryocoolers without any cryogen.
  • Hidehiro Kaneda, Daisuke Ishihara, Shinki Oyabu, Mitsuyoshi Yamagishi, Takehiko Wada, Mitsunobu Kawada, Naoki Isobe, Kentaroh Asano, Toyoaki Suzuki, Takao Nakagawa, Hideo Matsuhara, Itsuki Sakon, Kohji Tsumura, Hiroshi Shibai, Taro Matsuo
    SPACE TELESCOPES AND INSTRUMENTATION 2016: OPTICAL, INFRARED, AND MILLIMETER WAVE 9904 2016年  査読有り
    SMI (SPICA Mid-infrared Instrument) is one of the two focal-plane scientific instruments planned for new SPICA, and the Japanese instrument proposed and managed by a university consortium in Japan. SMI covers the wavelength range of 12 to 36 mu m, using the following three spectroscopic channels with unprecedentedly high sensitivities: low-resolution spectroscopy (LRS; R = 50 - 120, 17 - 36 mu m), mid-resolution spectroscopy (MRS; R = 1300 - 2300, 18 - 36 mu m), and high-resolution spectroscopy (HRS; R = 28000, 12 - 18 mu m). The key functions of these channels are high-speed dust-band mapping with LRS, high-sensitivity multi-purpose spectral mapping with MRS, and high-resolution molecular-gas spectroscopy with HRS. This paper describes the technical concept and scientific capabilities of SMI.
  • Seong Jin Kim, Hyung Mok Lee, Woong-Seob Jeong, Tomotsugu Goto, Hideo Matsuhara, Myungshin Im, Hyunjin Shim, Min Gyu Kim, Myung Gyoon Lee
    MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 454(2) 1573-1584 2015年9月15日  査読有り
    We present mid-infrared (MIR) luminosity functions (LFs) of local star-forming (SF) galaxies in the AKARI NEP-Wide Survey field. In order to derive more accurate luminosity function, we used spectroscopic sample only. Based on the NEP-Wide point source catalogue containing a large number of infrared (IR) sources distributed over the wide (5.4 sq. deg.) field, we incorporated the spectroscopic redshift data for about 1790 selected targets obtained by optical follow-up surveys with MMT/Hectospec and WIYN/Hydra. The AKARI continuous 2 to 24 micron wavelength coverage as well as photometric data from optical u band to NIR H-band with the spectroscopic redshifts for our sample galaxies enable us to derive accurate spectral energy distributions (SEDs) in the mid-infrared. We carried out SED fit analysis and employed 1/Vmax method to derive the MIR (8, 12, and 15 micron rest-frame) luminosity functions. We fit our 8 micron LFs to the double power-law with the power index of alpha= 1.53 and beta= 2.85 at the break luminosity. We made extensive comparisons with various MIR LFs from several literatures. Our results for local galaxies from the NEP region are generally consistent with other works for different fields over wide luminosity ranges. The comparisons with the results from the NEP-Deep data as well as other LFs imply the luminosity evolution from higher redshifts towards the present epoch.
  • Kazumi Murata, Yusei Koyama, Masayuki Tanaka, Hideo Matsuhara, Tadayuki Kodama
    ASTRONOMY & ASTROPHYSICS 581 2015年7月1日  査読有り
    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. PAH emission reflects the physical conditions of galaxies and dominates 8 um luminosity (L8), which can directly be measured with the L15 band of AKARI. L8 to infrared luminosity (LIR) ratio is used as a tracer of the PAH strength. Both photometric and spectroscopic redshifts are applied to identify the cluster members. The L15-band-detected galaxies tend to reside in the outskirt of the cluster and have optically green colour, R-z'~ 1.2. We find no clear difference of the L8/LIR behaviour of galaxies in field and cluster environment. The L8/LIR of cluster galaxies decreases with specific-star-formation rate divided by that of main-sequence galaxies, and with LIR, consistent with the results for field galaxies. The relation between L8/LIR and LIR is between those at z=0 and z=2 in the literature. Our data also shows that starburst galaxies, which have lower L8/LIR than main-sequence, are located only in the outskirt of the cluster. All these findings extend previous studies, indicating that environment affects only the fraction of galaxy types and does not affect the L8/LIR behaviour of star-forming galaxies.
  • Tomotsugu Goto, Takehiko Wada, Hideo Matsuhara, the AKARI NEP team, the AKARI all sky survey team, the SPICA MCS team
    2015年6月29日  
    Infrared (IR) luminosity is fundamental to understanding the cosmic star formation history and AGN evolution, since their most intense stages are often obscured by dust. Japanese infrared satellite, AKARI, provided unique data sets to probe these both at low and high redshifts. The AKARI performed an all sky survey in 6 IR bands (9, 18, 65, 90, 140, and 160$\mu$m) with 3-10 times better sensitivity than IRAS, covering the crucial far-IR wavelengths across the peak of the dust emission. Combined with a better spatial resolution, AKARI can measure the total infrared luminosity ($L_{TIR}$) of individual galaxies much more precisely, and thus, the total infrared luminosity density of the local Universe. In the AKARI NEP deep field, we construct restframe 8$\mu$m, 12$\mu$m, and total infrared (TIR) luminosity functions (LFs) at 0.15$<z<$2.2 using 4128 infrared sources. A continuous filter coverage in the mid-IR wavelength (2.4, 3.2, 4.1, 7, 9, 11, 15, 18, and 24$\mu$m) by the AKARI satellite allows us to estimate restframe 8$\mu$m and 12$\mu$m luminosities without using a large extrapolation based on a SED fit, which was the largest uncertainty in previous work. By combining these two results, we reveal dust-hidden cosmic star formation history and AGN evolution from $z$=0 to $z$=2.2, all probed by the AKARI satellite. The next generation space infrared telescope, SPICA, will revolutionize our view of the infrared Universe with superb sensitivity of the cooled 3m space telescope. We conclude with our survey proposal and future prospects with SPICA.
  • Yoshiki Toba, Tohru Nagao, Michael A. Strauss, Kentaro Aoki, Tomotsugu Goto, Masatoshi Imanishi, Toshihiro Kawaguchi, Yuichi Terashima, Yoshihiro Ueda, James Bosch, Kevin Bundy, Yoshiyuki Doi, Hanae Inami, Yutaka Komiyama, Robert H. Lupton, Hideo Matsuhara, Yoshiki Matsuoka, Satoshi Miyazaki, Tomoki Morokuma, Fumiaki Nakata, Nagisa Oi, Masafusa Onoue, Shinki Oyabu, Paul Price, Philip J. Tait, Tadafumi Takata, Manobu M. Tanaka, Tsuyoshi Terai, Edwin L. Turner, Tomohisa Uchida, Tomonori Usuda, Yousuke Utsumi, Shiang-Yu Wang, Yoshihiko Yamada
    PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 67(5) 2015年6月1日  査読有り
    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 $i - [22] > 7.0$, where $i$, $K_\mathrm{s}$, and [22] represent AB magnitude in the $i$-band, $K_\mathrm{s}$-band, and 22 $\mu$m, respectively, in the GAMA 14hr field ($\sim$ 9 deg$^2$). Among these objects, 31 ($\sim$ 65 %) show power-law spectral energy distributions (SEDs) in the near-IR (NIR) and MIR regime, while the remainder show a NIR bump in their SEDs. Assuming that the redshift distribution for our DOGs sample is Gaussian, with mean and sigma $z$ = 1.99 $\pm$ 0.45, we calculated their total IR luminosity using an empirical relation between 22 $\mu$m luminosity and total IR luminosity. The average value of the total IR luminosity is (3.5 $\pm$ 1.1) $\times$ $10^{13}$ L$_{\odot}$, which classifies them as hyper-luminous infrared galaxies (HyLIRGs). We also derived the total IR luminosity function (LF) and IR luminosity density (LD) for a flux-limited subsample of 18 DOGs with 22 $\mu$m flux greater than 3.0 mJy and with $i$-band magnitude brighter than 24 AB magnitude. The derived space density for this subsample is log $\phi$ = -6.59 $\pm$ 0.11 [Mpc$^{-3}$]. The IR LF for DOGs including data obtained from the literature is well fitted by a double-power law. The derived lower limit for the IR LD for our sample is $\rho_{\mathrm{IR } }$ $\sim$ 3.8 $\times$ 10$^7$ [L$_{\odot}$ Mpc$^{-3}$] and its contributions to the total IR LD, IR LD of all ultra-luminous infrared galaxies (ULIRGs), and that of all DOGs are $>$ 3 %, $>$ 9 %, and $>$ 15 %, respectively.
  • Dohyeong Kim, Myungshin Im, Ji Hoon Kim, Hyunsung David Jun, Jong-Hak Woo, Hyung Mok Lee, Myung Gyoon Lee, Takao Nakagawa, Hideo Matsuhara, Takehiko Wada, Shinki Oyabu, Toshinobu Takagi, Youichi Ohyama, Seong-Kook Lee
    2015年3月17日  
    We present 2.5-5.0 $\mu$m spectra of 83 nearby ($0.002\,<\,z\,<\,0.48$) and bright ($K<14$mag) type-1 active galactic nuclei (AGNs) taken with the Infrared Camera (IRC) on board $\it{AKARI}$. The 2.5-5.0 $\mu$m spectral region contains emission lines such as Br$\beta$ (2.63 $\mu$m), Br$\alpha$ (4.05 $\mu$m), and polycyclic aromatic hydrocarbons (PAH; 3.3 $\mu$m), which can be used for studying the black hole (BH) masses and star formation activities in the host galaxies of AGNs. The spectral region also suffers less dust extinction than in the ultra violet (UV) or optical wavelengths, which may provide an unobscured view of dusty AGNs. Our sample is selected from bright quasar surveys of Palomar-Green (PG) and SNUQSO, and AGNs with reverberation-mapped BH masses from Peterson et al. (2004). Using 11 AGNs with reliable detection of Brackett lines, we derive the Brackett-line-based BH mass estimators. We also find that the observed Brackett line ratios can be explained with the commonly adopted physical conditions of the broad line region (BLR). Moreover, we fit the hot and warm dust components of the dust torus by adding photometric data of SDSS, 2MASS, $\it{WISE}$, and $\it{ISO}$ to the $\it{AKARI}$ spectra, finding hot and warm dust temperatures of $\sim1100\,\rm{K}$ and $\sim220\,\rm{K}$, respectively, rather than the commonly cited hot dust temperature of 1500 K.
  • Yiseul Jeon, Myungshin Im, Eugene Kang, Hyung Mok Lee, Hideo Matsuhara
    2015年3月10日  
    We present the J and H-band source catalog covering the AKARI North Ecliptic Pole field. Filling the gap between the optical data from other follow-up observations and mid-infrared (MIR) data from AKARI, our near-infrared (NIR) data provides contiguous wavelength coverage from optical to MIR. For the J and H-band imaging, we used the FLoridA Multi-object Imaging Near-ir Grism Observational Spectrometer (FLAMINGOS) on the Kitt Peak National Observatory 2.1m telescope covering a 5.1 deg2 area down to a 5 sigma depth of ~21.6 mag and ~21.3 mag (AB) for J and H-band with an astrometric accuracy of 0.14" and 0.17" for 1 sigma in R.A. and Decl. directions, respectively. We detected 208,020 sources for J-band and 203,832 sources for H-band. This NIR data is being used for studies including analysis of the physical properties of infrared sources such as stellar mass and photometric redshifts, and will be a valuable dataset for various future missions.
  • Takuji Yamashita, Hideo Matsuhara, Shinya Komugi
    Proceedings of the International Symposium “Nanoscience and Quantum Physics 2012” (nanoPHYS’12) 2015年1月15日  
  • Tadahito Mizutani, Toshihiko Yamawaki, Keiji Komatsu, Ken Goto, Shinsuke Takeuchi, Keisuke Shinozaki, Hideo Matsuhara, Takao Nakagawa
    Journal of Astronomical Telescopes, Instruments, and Systems 1(2) 2015年  
    The infrared space telescope SPICA (Space Infrared Telescope for Cosmology and Astrophysics) is a next-generation astronomical project of the Japan Aerospace Exploration Agency, which features a 3 m class and 6 K cryogenically cooled space telescope. This paper outlines the current status for the preliminary structural design of the SPICA payload module. Dedicated studies were conducted for key technologies to enhance the design accuracy of the SPICA cryogenic assembly and mitigate the development risk. One of the results is described for the concept of the on-orbit truss separation mechanisms, which aim to both reduce the heat load from the main truss assembly and isolate the microvibration by changing the natural frequency of the spacecraft.
  • Keisuke Shinozaki, Yoichi Sato, Kenichiro Sawada, Makiko Ando, Hiroyuki Sugita, Toshihiro Yamawaki, Tadahiro Mizutani, Keiji Komatsu, Takao Nakagawa, Hiroshi Murakami, Hideo Matsuhara, Makoto Takada, Shigeki Takai, Akinobu Okabayashi, Shoji Tsunematsu, Kenichi Kanao, Katsuhiro Narasaki
    CRYOGENICS 64 228-234 2014年11月  
    SPace Infrared telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched around 2020. The SPICA is transferred into a halo orbit around the second Lagrangian point (L2) in the Sun-Earth system, which enables us to use effective radiant cooling in combination with mechanical cooling system in order to cool a 3 m large IR telescope below 6 K. At a present, a conceptional study of SPICA is underway to assess and mitigate mission's risks; the thermal study for the risk mitigation sets a goal of a 25% margin on cooling power of 4 K/1 K temperature regions, a 25% margin on the heat load from Focal Plane Instruments (FPls) at intermediated temperature region, to enhance the reliability of the mechanical cooler system, and to enhance feasibility of ground tests. Thermal property measurements of FRP materials are also important. This paper introduces details of the thermal design study for risk mitigation, including development of the truss separation mechanism, the cryogenic radiator, mechanical cooler system, and thermal property measurements of materials. (C) 2014 Elsevier Ltd. All rights reserved.
  • Murata, K., Matsuhara, H., Inami, H., Wada, T., Goto, T., Armus, L., Pearson, C., Serjeant, S., Miyaji, T.
    Astronomy and Astrophysics 566 2014年6月  査読有り
    We study the behaviour of polycyclic aromatic hydrocarbon (PAH) emission in galaxies at z = 0.3-1.4 using 1868 samples from the revised catalogue of AKARI North Ecliptic Pole Deep survey. The continuous filter coverage at 2-24 μm makes it possible to measure 8 μm luminosity, which is dominated by PAH emission, for galaxies at up to z = 2. We compare the IR8 (≡LIR/L(8)) and 8 μm to 4.5 μm luminosity ratio (νL(8) /νL(4.5)) with the starburstiness, RSB, defined as excess of specific star-formation rate over that of main-sequence galaxy. All AGN candidates were excluded from our sample using a spectral energy distribution fitting. We find νL(8) /νL(4.5) increases with starburstiness at log RSB&lt; 0.5 and stays constant at higher starburstiness. On the other hand, IR8 is constant at log RSB&lt; 0, while it increases with starburstiness at log RSB&gt; 0. This behaviour is seen in all redshift range of our study. These results indicate that starburst galaxies have deficient PAH emission compared with main-sequence galaxies. We also find that galaxies with extremely high νL(8) /νL(4.5) ratio have only moderate starburstiness. These results suggest that starburst galaxies have compact star-forming regions with intense radiation, which destroys PAHs, and/or have dusty HII regions resulting in a lack of ionising photons....
  • Yoshiki Toba, Shinki Oyabu, Hideo Matsuhara, Matthew A. Malkan, Poshak Gandhi, Takao Nakagawa, Naoki Isobe, Mai Shirahata, Nagisa Oi, Youichi Ohyama, Satoshi Takita, Chisato Yamauchi, Kenichi Yano
    2014年4月19日  
    In this work, we investigate the dependence of the covering factor (CF) of active galactic nuclei (AGNs) (i) on the mid-infrared (MIR) luminosity and (ii) on the redshift. We constructed 12- and 22-micron luminosity functions (LFs) at 0.006 < z < 0.3 using the Wide-field Infrared Survey Explorer} (WISE) data. Combining the WISE catalog with the Sloan Digital Sky Survey (SDSS) spectroscopic data, we selected 223,982 galaxies at 12 micron and 25,721 galaxies at 22 micron for spectroscopic classification. We then identified 16,355 AGNs at 12 micron and 4,683 AGNs at 22 micron by their optical emission lines and cataloged classifications in the SDSS. Following that, we estimated the CF as the fraction of type 2 AGN in all AGNs whose MIR emissions are dominated by the active nucleus (not their host galaxies) based on their MIR colors. We found that (i) the CF decreased with increasing MIR luminosity, regardless of the choice of type 2 AGN classification criteria, and (ii) the CF did not change significantly with the redshift for z < 0.2. Furthermore, we carried out various tests to determine the influence of selection bias and confirmed similar dependences exist even when taking these uncertainties into account. The luminosity dependence of the CF can be explained by the receding torus model, but the "modified" receding torus model gives a slightly better fit, as suggested by Simpson.
  • Nagisa Oi, Hideo Matsuhara, Kazumi Murata, Tomotsugu Goto, Takehiko Wada, Toshinobu Takagi, Youichi Ohyama, Matthew Malkan, Myungshin Im, Hyunjin Shim Shim, Stephen Serjeant, Chris Pearson
    ASTRONOMY & ASTROPHYSICS 566 2014年3月31日  査読有り
    Aims. We present an 8-band (u*, g', r', i', z', Y, J, Ks) optical to NIR deep photometric catalog based on the observations made with MegaCam and WIRCam at CFHT, and compute photometric redshifts, zp in the North Ecliptic Pole (NEP) region. Our catalog provides us to identify the counterparts, and zp for AKARI NIR/MIR sources. Results. The estimated 4sigma detection limits within an 1" aperture radius are 26.7, 25.9, 25.1, and 24.1 mag [AB] for g', r', i', and z'-bands and 23.4, 23.0, and 22.7 mag for Y, J, and Ks-bands, respectively. There are a total of 85797 sources in the band-merged catalog. An astrometric accuracy of this catalog determined by examining coordinate offsets with regard to 2MASS is 0.013" with a root mean square offset of 0.32". We distinguish 5441 secure stars from extended sources using u*-J vs. g'-Ks colors, combined with the SExtractor stellarity index of the images. Comparing with galaxy spectroscopic redshifts, we find a photometric redshift dispersion, sigma_(dz/(1+z)), of 0.032 and catastrophic failure rate, dz/(1+z)>0.15, of 5.8% at z<1, while a dispersion of 0.117 and a catastrophic failures rate of 16.6% at z>1. We extend estimate of the zp uncertainty over the full magnitude/redshift space with a redshift probability distribution function and find that our redshift are highly accurate with z'<22 at zp<2.5 and for fainter sources with z'<24 at z<1. From the investigation of photometric properties of AKARI infrared sources (23354 sources) using the g'z'Ks diagram, <5% of AKARI sources with optical counterparts are classified as high-z (1.4<z<2.5) star-forming galaxies. Among the high-z star-forming galaxies, AKARI MIR detected sources seem to be affected by stronger dust extinction compared with sources with non-detections in the AKARI MIR bands. The full, electronic version of our catalog with zp will be available at the CDS.
  • Takao Nakagawa, Hiroshi Shibai, Takashi Onaka, Hideo Matsuhara, Hidehiro Kaneda, Yasuhiro Kawakatsu, Peter Roelfsema
    Proceedings of SPIE - The International Society for Optical Engineering 9143 2014年  
    We present the current status of SPICA (Space Infrared Telescope for Cosmology and Astrophysics), which is a mission optimized for mid- and far-infrared astronomy with a cryogenically cooled 3.2 m telescope. SPICA is expected to achieve high spatial resolution and unprecedented sensitivity in the mid- and far-infrared, which will enable us to address a number of key problems in present-day astronomy, ranging from the star-formation history of the universe to the formation of planets. We have carried out the "Risk Mitigation Phase" activity, in which key technologies essential to the realization of the mission have been extensively developed. Consequently, technical risks for the success of the mission have been significantly mitigated. Along with these technical activities, the international collaboration framework of SPICA had been revisited, which resulted in maintenance of SPICA as a JAXA-led mission as in the original plan but with larger contribution of ESA than that in the original plan. To enable the ESA participation, a SPICA proposal to ESA is under consideration as a medium-class mission under the framework of the ESA Cosmic Vision. The target launch year of SPICA under the new framework is FY2025.
  • Keisuke Shinozaki, Yoichi Sato, Kenichiro Sawada, Makiko Ando, Hiroyuki Sugita, Toshihiko Yamawaki, Tadahito Mizutani, Keiji Komatsu, Shun Okazaki, Hiroyuki Ogawa, Takao Nakagawa, Hideo Matsuhara, Makoto Takada, Akinobu Okabayashi, Shoji Tsunematsu, Katsuhiro Narasaki
    SPACE TELESCOPES AND INSTRUMENTATION 2014: OPTICAL, INFRARED, AND MILLIMETER WAVE 9143 2014年  
    The Space Infrared Telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched around 2025. The SPICA mission is to be launched into a halo orbit around the second Lagrangian point in the Sun-Earth system, which allows us to use effective radiant cooling in combination with a mechanical cooling system in order to cool a 3m large IR telescope below 6K. The use of 4K / 1K-class Joule-Thomson coolers is proposed in order to cool the telescope and provide a 4K / 1K temperature region for Focal Plane Instruments (FPIs). This paper introduces details of the thermal design study for the SPICA payload module in the Risk-Mitigation-Phase (RMP), in which the activity is focused on mitigating the mission's highest risks. As the result of the RMP activity, most of all the goals have been fully satisfied and the thermal design of the payload module has been dramatically improved.
  • Inami, H., Armus, L., Charmandaris, V., Groves, B., Kewley, L., Petric, A., Stierwalt, S., Díaz-Santos, T., Surace, J., Rich, J., Haan, S., Howell, J., Evans, A. S., Mazzarella, J., Marshall, J., Appleton, P., Lord, S., Spoon, H., Frayer, D., Matsuhara, H., Veilleux, S.
    The Astrophysical Journal 777(2) 2013年11月  査読有り
    We present the data and our analysis of mid-infrared atomic fine-structure emission lines detected in Spitzer/Infrared Spectrograph high-resolution spectra of 202 local Luminous Infrared Galaxies (LIRGs) observed as part of the Great Observatories All-sky LIRG Survey (GOALS). We readily detect emission lines of [S IV], [Ne II], [Ne V], [Ne III], [S III]18.7 μm, [O IV], [Fe II], [S III]33.5 μm, and [Si II]. More than 75% of these galaxies are classified as starburst-dominated sources in the mid-infrared, based on the [Ne V]/[Ne II] line flux ratios and equivalent width of the 6.2 μm polycyclic aromatic hydrocarbon feature. We compare ratios of the emission-line fluxes to those predicted from stellar photo-ionization and shock-ionization models to constrain the physical and chemical properties of the gas in the starburst LIRG nuclei. Comparing the [S IV]/[Ne II] and [Ne III]/[Ne II] line ratios to the Starburst99-Mappings III models with an instantaneous burst history, the emission-line ratios suggest that the nuclear starbursts in our LIRGs have ages of 1-4.5 Myr, metallicities of 1-2 Z , and ionization parameters of 2-8 × 107 cm s-1. Based on the [S III]33.5 μm/[S III]18.7 μm ratios, the electron density in LIRG nuclei is typically one to a few hundred cm-3, with a median electron density of ~300 cm-3, for those sources above the low density limit for these lines. We also find that strong shocks are likely present in 10 starburst-dominated sources of our sample. A significant fraction of the GOALS sources (80) have resolved neon emission-line profiles (FWHM &gt;=600 km s-1) and five show clear differences in the velocities of the [Ne III] or [Ne V] emission lines, relative to [Ne II], of more than 200 km s-1. Furthermore, six starburst and five active galactic nucleus dominated LIRGs show a clear trend of increasing line width with ionization potential, suggesting the possibility of a compact energy source and stratified interstellar medium in their nuclei. We confirm a strong correlation between the sum of the [Ne II]12.8 μm and [Ne III]15.5 μm emission, as well as [S III]33.5 μm, with both the infrared luminosity and the 24 μm warm dust emission measured from the spectra, consistent with all three lines tracing ongoing star formation. Finally, we find no correlation between the hardness of the radiation field or the emission-line width and the ratio of the total infrared to 8 μm emission (IR8), a measure of the strength of the starburst and the distance of the LIRGs from the star-forming main sequence. This may be a function of the fact that the infrared luminosity and the mid-infrared fine-structure lines are sensitive to different timescales over the starburst, or that IR8 is more sensitive to the geometry of the region emitting the warm dust than the radiation field producing the H II region emission....
  • Fumi Egusa, Takehiko Wada, Itsuki Sakon, Takashi Onaka, Ko Arimatsu, Hideo Matsuhara
    ASTROPHYSICAL JOURNAL 778(1) 2013年10月1日  査読有り
    Using mid-infrared (MIR) images of four photometric bands of the Infrared Camera (IRC) onboard the AKARI satellite, S7 (7 um), S11 (11 um), L15 (15 um), and L24 (24 um), we investigate the interstellar dust properties of the nearby pair of galaxies M51 with respect to its spiral arm structure. The arm and interarm regions being defined based on a spatially filtered stellar component model image, we measure the arm-to-interarm contrast for each band. The contrast is lowest in the S11 image, which is interpreted as that among the four AKARI MIR bands the S11 image best correlates with the spatial distribution of dust grains including colder components, while the L24 image with the highest contrast traces warmer dust heated by star forming activities. The surface brightness ratio between the bands, i.e. color, is measured over the disk of the main galaxy, M51a, at 300 pc resolution. We find that the distribution of S7/S11 is smooth and well traces the global spiral arm pattern while L15/S11 and L24/S11 peak at individual HII regions. This result indicates that the ionization state of PAHs is related to the spiral structure. Comparison with observational data and dust models also supports the importance of the variation in the PAH ionization state within the M51a disk. However, the mechanism driving this variation is not yet clear from currently available data sets. Another suggestion from the comparison with the models is that the PAH fraction to the total dust mass is higher than previously estimated.
  • Marios Karouzos, Myungshin Im, Markos Trichas, Angel Ruiz, Tomo Goto, Matt Malkan, Yiseul Jeon, Ji Hoon Kim, Hyung Mok Lee, Seongjin Kim, Nagisa Oi, Hideo Matsuhara, Toshinobu Takagi, Kazumi Murata, Takehiko Wada, Kensuke Wada, Hyunjin Shim, Hitoshi Hanami, Stephen Serjeant, Glenn J. White, Chris Pearson, Youichi Ohyama
    ASTROPHYSICAL JOURNAL 784(2) 2013年9月27日  査読有り
    Several lines of argument support the existence of a link between activity at the nuclei of galaxies, in the form of an accreting supermassive black hole, and star-formation activity in these galaxies. The exact nature of this link is still under debate. Radio jets have long been argued to be an ideal mechanism that allows AGN to interact with their host galaxy and regulate star-formation. In this context, we are using a sample of radio sources in the North Ecliptic Pole (NEP) field to study the nature of the putative link between AGN activity and star-formation. This is done by means of spectral energy distribution (SED) fitting. We use the excellent spectral coverage of the AKARI infrared space telescope together with the rich ancillary data available in the NEP to build SEDs extending from UV to far-IR wavelengths. Through SED fitting we constrain both the AGN and host galaxy components. We find a significant AGN component in our sample of relatively faint radio-sources ($<$mJy), that increases in power with increasing radio-luminosity. At the highest radio-luminosities, the presence of powerful jets dominates the radio emission of these sources. A positive correlation is found between the luminosity of the AGN component and that of star-formation in the host galaxy, independent of the radio luminosity. By contrast, for a given redshift and AGN luminosity, we find that increasing radio-luminosity leads to a decrease in the specific star-formation rate. The most radio-loud AGN are found to lie on the main sequence of star-formation for their respective redshifts. For the first time, such a two-sided feedback process is seen in the same sample. We conclude that radio jets do suppress star-formation in their host galaxies but appear not to totally quench it. Our results therefore support the maintenance nature of "radio-mode" feedback from radio-AGN jets.
  • Chris Sedgwick, Stephen Serjeant, Chris Pearson, Ian Smail, Myungshin Im, Shinki Oyabu, Toshinobu Takagi, Hideo Matsuhara, Takehiko Wada, Hyung Mok Lee, Woong-Seob Jeong, Glenn J. White
    2013年8月26日  
    We present tentative H-alpha emission line detections of four submillimetre-detected galaxies at z>3.5: the radio galaxies 8C1909+722 and 4C60.07 at signal-to-noise ratios (SNRs) of 3.1 and 2.5, and two submillimetre-selected galaxies (SMGs) near the first of these at SNRs of 10.0 and 2.4, made with the AKARI Space Telescope as part of the FUHYU mission program. These are the highest-redshift H-alpha detections in such galaxies, made possible by AKARI's unique near-infrared spectroscopic capability. The two radio galaxies had known redshifts and surrounding structure, and we have detected broad H-alpha components indicating the presence of dust-shrouded quasars. We conclude that powerful AGNs at z>3.5 occur in peaks of the star-formation density fields, supporting a close connection between stellar mass build-up and black hole mass assembly at this redshift. We also show that 4C60.07 is a binary AGN. The H-alpha detections of the two SMGs are the first redshift determinations for these sources, confirming their physical association around their companion radio galaxy. The H-alpha-derived star formation rates (SFRs) for the SMGs are lower than their far-infrared derived SFRs by a factor of ~10, suggesting a level of dust obscuration similar to that found in studies at ~1<z<2.7.
  • Yoshiki Toba, Shinki Oyabu, Hideo Matsuhara, Matthew A. Malkan, Daisuke Ishihara, Takehiko Wada, Youichi Ohyama, Satoshi Takita, Chisato Yamauchi
    PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 65(5) 2013年8月11日  査読有り
    We present the 9 and 18 micron luminosity functions (LFs) of galaxies at 0.006 < z < 0.8 (with an average redshift of ~ 0.04) using the AKARI mid-infrared all-sky survey catalog. We selected 243 galaxies at 9 micron and 255 galaxies at 18 micron from the Sloan Digital Sky Survey (SDSS) spectroscopy region. These galaxies were then classified by their optical emission lines, such as the line width of H_alpha or by their emission line ratios of [OIII]/H_beta and [NII]/H_alpha into five types: Type 1 active galactic nuclei (AGN) (Type 1); Type 2 AGN (Type 2); low-ionization narrow emission line galaxies (LINER); galaxies with both star formation and narrow-line AGN activity (composite galaxies); and star-forming galaxies (SF). We found that (i) the number density ratio of Type 2 to Type 1 AGNs is 1.73 +/- 0.36, which is larger than a result obtained from the optical LF and (ii) this ratio decreases with increasing 18 micron luminosity.
  • Itsuki Sakon, Takashi Onaka, Hirokazu Kataza, Takehiko Wada, Yuki Sarugaku, Hideo Matsuhara, Takao Nakagawa, Naoto Kobayashi, Ciska Kemper, Youichi Ohyama, Toshio Matsumoto, Ji Yeon Seok
    Proceedings of Science 2013年  
    Mid-Infrared Camera and Spectrometers (MCS) is one of the Focal-Plane Instruments proposed for the SPICA mission in the pre-project phase. SPICA MCS is equipped with two spectrometers with different spectral resolution powers (R=Λ/δΛ); medium-resolution spectrometer (MRS) which covers 12-38μm with R≈1100-3000, and high-resolution spectrometer (HRS) which covers either 12-18μm with R≈30000. MCS is also equipped with Wide Field Camera (WFC), which is capable of performing multi-objects grism spectroscopy in addition to the imaging observation. A small slit aperture for low-resolution slit spectroscopy is planned to be placed just next to the field of view (FOV) aperture for imaging and slit-less spectroscopic observation. MCS covers an important part of the core spectral range of SPICA and, complementary with SAFARI (SpicA FAR-infrared Instrument), can do crucial observations for a number of key science cases to revolutionize our understanding of the lifecycle of dust in the universe. In this article, the latest design specification and the expected performance of the SPICA/MCS are introduced. Key science cases that should be targetted by SPICA/MCS have been discussed by the MCS science working group. Among such science cases, some of those related to dust science are briefly intriduced.
  • Takuji Yamashita, Shinya Komugi, Hideo Matsuhara, Lee Armus, Hanae Inami, Sabrina Stierwalt, Kotaro Kohno, Daisuke Iono, Ko Arimatsu
    NEW TRENDS IN RADIO ASTRONOMY IN THE ALMA ERA: THE 30TH ANNIVERSARY OF NOBEYAMA RADIO OBSERVATORY 476 297-298 2013年  
    We present results of the (CO)-C-12(J=1-0) survey of 46 nearby luminous infrared galaxies (LIRGs) from the Great Observatories All-sky LIRG Survey (GOALS). This survey aims to obtain molecular gas mass MH2 and to investigate the star-forming activity of local LIRGs. The estimated star formation efficiency (SFJ) is 9.0 +/- 5.5 Gyr(-1) in average, which is higher than normal lR galaxies but lower than ULIRGs. No clear correlation was found either between the S.Fh and the 6.2 mu m PAH equivalent width; an indicator of AGN activity, or between the SFE, and the stage of the galaxy merging.
  • Fumihiko Usui, Toshihiro Kasuga, Sunao Hasegawa, Masateru Ishiguro, Daisuke Kuroda, Thomas G. Mueller, Takafumi Ootsubo, Hideo Matsuhara
    ASTROPHYSICAL JOURNAL 762(1) 2012年11月13日  
    We present an analysis of the albedo properties of main belt asteroids detected by the All-Sky Survey of the infrared satellite AKARI. The characteristics of 5120 asteroids detected by the survey, including their sizes and albedos, were cataloged in the Asteroid Catalog Using AKARI (AcuA). Size and albedo measurements were based on the Standard Thermal Model, using inputs of infrared fluxes and absolute magnitudes. Main belt asteroids, which account for 4722 of the 5120 AcuA asteroids, have semimajor axes of 2.06 to 3.27 AU. AcuA provides a complete data set of all main belt asteroids brighter than the absolute magnitude of H < 10.3, which corresponds to the diameter of d > 20 km. We confirmed that the albedo distribution of the main belt asteroids is strongly bimodal as was already known from the past observations, and that the bimodal distribution occurs not only in the total population, but also within inner, middle, and outer regions of the main belt. We found that the small asteroids have much more variety in albedo than the large asteroids. In spite of the albedo transition process like space weathering, the heliocentric distribution of the mean albedo of asteroids in each taxonomic type is nearly flat. The mean albedo of the total, on the other hand, gradually decreases with an increase in semimajor axis. This can be explained by the compositional ratio of taxonomic types; that is, the proportion of dark asteroids such as C- and D-types increases, while that of bright asteroids such as S-type decreases, with increasing heliocentric distance. The heliocentric distributions of X-subclasses: E-, M-, and P-type, which can be divided based on albedo values, are also examined. P-type, which is the major component in X-types, are distributed throughout the main belt regions, and the abundance of P-type increases beyond 3 AU. This distribution is similar to that of C- or D-types.
  • Ji Hoon Kim, Myungshin Im, Hyung Mok Lee, Myung Gyoon Lee, Hyunsung David Jun, Takao Nakagawa, Hideo Matsuhara, Takehiko Wada, Shinki Oyabu, Toshinobu Takagi, Hanae Inami, Youichi Ohyama, Rika Yamada, George Helou, Lee Armus, Yong Shi
    ASTROPHYSICAL JOURNAL 760(2) 2012年10月5日  査読有り
    Polycyclic Aromatic Hydrocarbon (PAH) emission features dominate the mid-infrared spectra of star-forming galaxies and can be useful to calibrate star formation rates and diagnose ionized states of grains. However, the PAH 3.3 micron feature has not been studied as much as other PAH features since it is weaker than others and resides outside of Spitzer capability. In order to detect and calibrate the 3.3 micron PAH emission and investigate its potential as a star formation rate indicator, we carried out an AKARI mission program, AKARI mJy Unbiased Survey of Extragalactic Survey (AMUSES) and compare its sample with various literature samples. We obtained 2 ~5 micron low resolution spectra of 20 flux-limited galaxies with mixed SED classes, which yields the detection of the 3.3 micron PAH emission from three out of 20 galaxies. For the combined sample of AMUSES and literature samples, the 3.3 micron PAH luminosities correlate with the infrared luminosities of star-forming galaxies, albeit with a large scatter (1.5 dex). The correlation appears to break down at the domain of ultra-luminous infrared galaxies (ULIRGs), and the power of the 3.3 micron PAH luminosity as a proxy for the infrared luminosity is hampered at log[L(PAH3.3)/(erg/sec)] > -42.0. Possible origins for this deviation in the correlation are discussed, including contribution from AGN and strongly obscured YSOs, and the destruction of PAH molecules in ULIRGs.
  • Fumi Egusa, I. Sakon, T. Onaka, H. Matsuhara, K. Arimatsu, T. Suzuki, T. Wada, The IRC team The IRC team
    Publications of The Korean Astronomical Society 27(4) 253-256 2012年9月16日  
  • Glenn J. White, Bunyo Hatsukade, Chris Pearson, Toshinobu Takagi, Chris Sedgwick, Shuji Matsuura, Hideo Matsuhara, Stephen Serjeant, Takao Nakagawa, Hyung Mok Lee, Shinki Oyabu, Woong-Seob Jeong, Mai Shirahata, Kotaro Kohno, Issei Yamamura, Hitoshi Hanami, Tomotsugu Goto, Sin'itirou Makiuti, David L. Clements, K. Malek, Sophia A. Khan
    MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 427(3) 1830-1846 2012年7月10日  査読有り
    The results of a deep 20 cm radio survey at 20 cm are reported of the AKARI Deep Field South (ADF-S) near the South Ecliptic Pole (SEP), using the Australia Telescope Compact Array telescope, ATCA. The survey has 1 sigma detection limits ranging from 18.7--50 microJy per beam over an area of ~1.1 sq degrees, and ~2.5 sq degrees to lower sensitivity. The observations, data reduction and source count analysis are presented, along with a description of the overall scientific objectives, and a catalogue containing 530 radio sources detected with a resolution of 6.2" x 4.9". The derived differential source counts show a pronounced excess of sources fainter than ~1 mJy, consistent with an emerging population of star forming galaxies. Cross-correlating the radio with AKARI sources and archival data we find 95 cross matches, with most galaxies having optical R-magnitudes in the range 18-24 mag, and 52 components lying within 1" of a radio position in at least one further catalogue (either IR or optical). We have reported redshifts for a sub-sample of our catalogue finding that they vary between galaxies in the local universe to those having redshifts of up to 0.825. Associating the radio sources with the Spitzer catalogue at 24 microns, we find 173 matches within one Spitzer pixel, of which a small sample of the identifications are clearly radio loud compared to the bulk of the galaxies. The radio luminosity plot and a colour-colour analysis suggest that the majority of the radio sources are in fact luminous star forming galaxies, rather than radio-loud AGN. There are additionally five cross matches between ASTE or BLAST submillimetre galaxies and radio sources from this survey, two of which are also detected at 90 microns, and 41 cross-matches with submillimetre sources detected in the Herschel HerMES survey Public Data release.
  • Masaomi Tanaka, Takaya Nozawa, Itsuki Sakon, Takashi Onaka, Ko Arimatsu, Ryo Ohsawa, Keiichi Maeda, Takehiko Wada, Hideo Matsuhara, Hidehiro Kaneda
    ASTROPHYSICAL JOURNAL 749(2) 2012年2月20日  
    Most of the observational studies of supernova (SN) explosions are limited to early phases (< a few yr after the explosion) of extragalactic SNe and observations of SN remnants (> 100 yr) in our Galaxy or very nearby galaxies. SNe at the epoch between these two, which we call "transitional" phase, have not been explored in detail except for several extragalactic SNe including SN 1987A in the Large Magellanic Cloud. We present theoretical predictions for the infrared (IR) dust emissions by several mechanisms; emission from dust formed in the SN ejecta, light echo by circumstellar and interstellar dust, and emission from shocked circumstellar dust. We search for IR emission from 6 core-collapse SNe at the transitional phase in the nearby galaxies NGC 1313, NGC 6946, and M101 by using the data taken with the AKARI satellite and Spitzer. Among 6 targets, we detect the emission from SN 1978K in NGC 1313. SN 1978K is associated with 1.3 x 10^{-3} Msun of silicate dust. We show that, among several mechanisms, the shocked circumstellar dust is the most probable emission source to explain the IR emission observed for CSM-rich SN 1978K. IR emission from the other 5 objects is not detected. Our current observations are sensitive to IR luminosity of > 10^{38} erg s^{-1}, and the non-detection of SN 1962M excludes the existence of the shocked circumstellar dust for a high gas mass-loss rate of sim 10^{-4} Msun yr^{-1}. Observations of SNe at the transitional phase with future IR satellites will fill the gap of IR observations of SNe with the age of 10-100 years, and give a new opportunity to study the circumstellar and interstellar environments of the progenitor, and possibly dust formation in SNe.
  • Chris Sedgwick, Stephen Serjeant, Chris Pearson, Shuji Matsuura, Mai Shirahata, Shinki Oyabu, Tomotsugu Goto, Hideo Matsuhara, D. L. Clements, Mattia Negrello, Toshinobu Takagi, Glenn J White
    2012年2月7日  
    We present the first far-infrared luminosity function in the AKARI Deep Field South, a premier deep field of the AKARI Space Telescope, using spectroscopic redshifts obtained with AAOmega. To date, we have found spectroscopic redshifts for 389 galaxies in this field and have measured the local (z < 0.25) 90 micron luminosity function using about one-third of these redshifts. The results are in reasonable agreement with recent theoretical predictions.
  • T. Onaka, H. Matsuhara, T. Wada, D. Ishihara, Y. Ohyama, I. Sakon, T. Shimonishi, R. Ohsawa, T. I. Mori, F. Egusa, F. Usui, S. Takita, H. Murakami, S. Oyabu, M. Yamagishi, T. Mori, A. Mouri, T. Kondo, S. Suzuki, H. Kaneda, Y. Ita, T. Ootsubo
    Proceedings of SPIE - The International Society for Optical Engineering 8442 2012年  
    AKARI, the Japanese satellite mission dedicated to infrared astronomy was launched in 2006 February and exhausted its liquid helium in 2007 August. During the cold mission phase, the Infrared Camera (IRC) onboard carried out an all-sky survey at 9 and 18μm with better spatial resolution and higher sensitivity than IRAS. Both bands also have slightly shorter wavelength coverage than IRAS 12 and 25μm bands and thus provide different information on the infrared sky. All-sky image data of the IRC are now in the final processing and will be released to the public within a year. After the exhaustion of the cryogen, the telescope and focal plane instruments of AKARI had still been kept at sufficiently low temperatures owing to the onboard cryocooler. Near-infrared (NIR) imaging and spectroscopic observations with the IRC had continued until 2011 May, when the spacecraft had a serious problem in the power supply system that forced us to terminate the observation. The IRC carried out nearly 20000 pointing observations in total despite of its near-earth orbit. About a half of them were performed after the exhaustion of the cryogen in the spectroscopic modes, which provided high-sensitivity NIR spectra from 2 to 5μm without disturbance of the terrestrial atmosphere. During the warm mission phase, the temperature of the instrument gradually increased and changed the array operation conditions. We present a summary of AKARI/IRC observations, including the all-sky mid-infrared diffuse data as well as the data taken in the warm mission phase. © 2012 SPIE.
  • Y. Toba, S. Oyabu, H. Matsuhara, D. Ishihara, M. Malkan, T. Wada, H. Kataza, Y. Ohyama, S. Takita
    SPECTRAL ENERGY DISTRIBUTION OF GALAXIES (284) 228-+ 2012年  
    We present the first determination of the 18 mu m luminosity function (LF) of galaxies at 0.006 < z < 0.7 (the average redshift is similar to 0.04) using the AKARI mid-infrared All-Sky Survey catalogue. We have selected a 18 mu m flux-limited sample of 243 galaxies from the catalogue in the SDSS spectroscopic region. We then classified the sample into four types; Seyfert 1 galaxies (including QSOs), Seyfert 2 galaxies, LINERs and Star-Forming galaxies using mainly [OIII]/H beta vs. [NII]/H alpha line ratios obtained from the SDSS.As a result of constructing Seyfert 1 and Seyfert 2 LFs, we found the following results; (i) the number density ratio of Seyfert 2s to Seyfert 1s is 3.98 +/- 0.41 obtained from Sy1 and Sy2 LFs; this value is larger than the results obtained from optical LFs. (ii) the fraction of Sy2s in the entire AGNs may be anti-correlated with 18 mu m luminosity. These results suggest that the torus structure probably depends on the mid-infrared luminosity of AGNs and most of the AGNs in the local Universe are obscured by dust.
  • T. Kotani, K. Enya, T. Nakagawa, H. Matsuhara, H. Kataza, M. Kawada, M. Mita, K. Komatsu, H. Uchida, K. Fujiwara, S. Mitani, S. Sakai, K. Haze, H. Kaneda, S. Oyabu, D. Ishihara, T. Miyata, S. Sako, T. Nakamura, K. Asano, M. Tamura, J. Nishikawa, T. Yamashita, N. Narita, H. Hayano, S. Oya, E. Kokubo, Y. Itoh, T. Matsuo, M. Fukagawa, H. Shibai, M. Honda, N. Baba, N. Murakami, Y. K. Okamoto, S. Ida, M. Takami, L. Abe, O. Guyon, T. Yamamuro
    Proceedings of SPIE - The International Society for Optical Engineering 8442 2012年  
    We present the current status of the development of the SPICA Coronagraph Instrument (SCI). SPICA is a nextgeneration 3-meter class infrared telescope, which will be launched in 2022. SCI is high-contrast imaging, spectroscopic instrument mainly for direct detection and spectroscopy of extra-solar planets in the near-to-mid infrared wavelengths to characterize their atmospheres, physical parameters and evolutionary scenarios. SCI is now under the international review process. In this paper, we present a science case of SCI. The main targets of SCI, not only for direct imaging but also for spectroscopy, are young to matured giant planets. We will also show that some of known exoplanets by groundbased direct detection are good targets for SCI, and a number of direct detection planets that are suitable for SCI will be significantly increased in the next decade. Second, a general design of SCI and a key technology including a new highthroughput binary mask coronagraph, will be presented. Furthermore, we will show that SCI is potentially capable of achieving 10 contrast by a PSF subtraction method, even with a telescope pointing error. This contrast enhancement will be important to characterize low-mass and cool planets. © 2012 SPIE. -6
  • Yuki Sarugaku, Yuji Ikeda, Naoto Kobayashi, Takashi Sukegawa, Shigeru Sugiyama, Keigo Enya, Hirokazu Kataza, Hideo Matsuhara, Takao Nakagawa, Hideyo Kawakita, Sohei Kondo, Yasuhiro Hirahara, Chikako Yasui
    SPACE TELESCOPES AND INSTRUMENTATION 2012: OPTICAL, INFRARED, AND MILLIMETER WAVE 8442 2012年  
    We have been developing an immersion grating for high-resolution spectroscopy in the mid-infrared (MIR) wavelength region. A MIR (12-18 mu m) high-resolution (R = 20,000-30,000) spectrograph with the immersion grating is proposed for SPICA, Japanese next-generation space telescope. The instrument will be the world's first high-resolution spectrograph in space, and it would make great impacts on infrared astronomy. To realize a high-efficiency immersion grating, optical properties and machinability of bulk materials are the critical issues. There are three candidate materials with good MIR transmittance; CdTe (n = 2.65), CdZnTe (n = 2.65), and KRS5 (n = 2.30). From measurements of transmittance with FTIR and of homogeneity with phase-shifting interferometry at 1.55 mu m, we confirmed that CdZnTe is the best material that satisfies all the optical requirements. As for machinability, by appling Canon's diamond cutting (planing) technique, fine grooves that meet our requirement were successfully cut on flats for all the materials. We also managed to fabricate a small CdZnTe immersion grating, which shows a high grating efficiency from the air. For the reflective metal coating, we tried Au (with thin underlying layer of Cr) and Al on CdZnTe flats both by sputter deposition and vapor deposition. All samples are found to be robust under 77 K and some of them achieve required reflectivity. Despite several remaining technical issues, the fabrication of CdZnTe immersion grating appears to be sound.
  • Ituski Sakon, Takashi Onaka, Takafumi Ootsubo, Hideo Matsuhara, Jennifer Noble
    Proceedings of SPIE - The International Society for Optical Engineering 8442 2012年  
    We have investigated the on-orbit properties of the spectroscopic data taken with NIR channel of the Infrared Camera (IRC) onboard AKARI during the phases 1, 2 and 3. We have determined the boundary shape of the aperture mask of NIR channel by using the spectroscopic data of uniform zodiacal background emission. The information on the aperture mask shape is indispensable in modeling and subtracting the spectroscopic background patterns made by the diffuse background emission such as zodiacal emission and the Galactic cirrus emission. We also have examined the wavelength dependency on the profile of the point spread function and its effect on the spectroscopic data. The obtained information is useful, for example, in reducing the spectroscopic data of a point source badly affected by bad pixels and in decomposing the overlapping spectra of sources that are aligned in the dispersion direction with a small offset the cross dispersion direction. In this paper, we summarize the supplementary knowledge that will be useful for the advanced data reduction procedures of NIR spectroscopic datasets. © 2012 SPIE.
  • H. Matsuhara, T. Nakagawa, Y. Kawakatsu, H. Murakami, M. Kawada, H. Sugita, T. Yamawaki, S. Mitani, K. Shinozaki, Y. Sato, G. Crone, K. Isaak, A. Heske
    Proceedings of SPIE - The International Society for Optical Engineering 8442 2012年  
    The Space Infrared Telescope for Cosmology and Astrophysics (SPICA) is a 3.2m cooled (below 6K) telescope mission which covers mid- and far-IR waveband with unprecedented sensitivity. An overview of recent design updates of the Scientific Instrument Assembly (SIA), composed of the telescope assembly and the instrument optical bench equipped with Focal Plane Instruments (FPIs) are presented. The FPI international science and engineering review is on-going to determine the FPI suite onboard SPICA: at present the mandatory instruments and functions to perform the unique science objectives of the SPICA mission are now consolidated. The final decision on the composition of the FPI suite is expected in early 2013. Through the activities in the current preproject phase, several key technical issues which impact directly on the instruments' performances and the science requirements and the observing efficiency have been identified, and extensive works are underway both at instrument and spacecraft level to resolve these issues and to enable the confirmation of the SPICA FPI suite. © 2012 SPIE.
  • Takehiko Wada, Hirokazu Kataza, Hideo Matsuhara, Mitsunobu Kawada, Daisuke Ishihara
    SPACE TELESCOPES AND INSTRUMENTATION 2012: OPTICAL, INFRARED, AND MILLIMETER WAVE 8442 2012年  査読有り
    Mid-infrared Camera and Spectrometer (MCS) is one of focal plane instruments for SPICA (Space Infrared Telescope for Cosmology and Astrophysics), which have 3 m class 6 K cooled telescope. MCS will provide wide field imaging and low-, medium-, and high-resolution spectroscopic observing capabilities with 7 detectors in the wavelength range from 5 to 38 micron. Large format array detectors are required in order to realize wide field of view in imaging and wide spectral coverage in spectroscopy. We are planning to cover the wavelength range of 5-26 micron by Si: As IBC 2K x 2K and 20-38 micron by Si:Sb BIB 1K x 1K. The development status and their design including the electrical and thermal design are described.
  • Toshinobu Takagi, Hideo Matsuhara, Takehiko Wada, Youichi Ohyama
    SPECTRAL ENERGY DISTRIBUTION OF GALAXIES (284) 456-459 2012年  査読有り
    Using extensive mid-IR datasets from AKARI, i.e. 9 band photometry covering the wavelength range from 2 mu m to 24 mu m and the unbiased spectroscopic survey for sources with S-v (9 mu m)&gt; 0.3 mJy, we investigated the PAHs emission features in distant starburst galaxies. PAH-selected galaxies, selected with an extremely red mid-IR colour due to PAHs, are found to have a peculiar rest-frame 11-to-8 mu m flux ratio, which is systematically smaller than nearby starburst/AGN spectral templates. This may indicate a systematic difference in the physical condition of the ISM between nearby and distant starburst galaxies.
  • Toru Yamada, Ikuru Iwata, Makiko Ando, Mamoru Doi, Tomotsugu Goto, Yuji Ikeda, Masatoshi Imanishi, Akio K. Inoue, Satoru Iwamura, Nobuyuki Kawai, Masakazu A. R. Kobayashi, Tadayuki Kodama, Yutaka Komiyama, Mariko Kubo, Hideo Matsuhara, Ken Mawatari, Matsuokak Yoshiki, Tomoki Morokuma, Hidehiko Nakaya, Kouji Ohta, Atsushi Okamoto, Sinki Oyabu, Yoichi Sato, Hiroyuki Sugita, Ryo Tsutsui, Chihiro Tokoku, Jun Toshikawa, Saku Tsuneta, Takehiko Wada, Kiyoto Yabe, Naoki Yasuda, Daisuke Yonetoku
    SPACE TELESCOPES AND INSTRUMENTATION 2012: OPTICAL, INFRARED, AND MILLIMETER WAVE 8442 2012年  査読有り
    WISH, Wide-field Imaging Surveyor for High-redshiftt, is a space mission concept to conduct very deep and wide-field surveys at near infrared wavelength at 1-5 mu m to study the properties of galaxies at very high redshift beyond the epoch of cosmic reionization. The concept has been developed and studied since 2008 to be proposed for future JAXA/ISAS mission. WISH has a 1.5m-diameter primary mirror and a wide-field imager covering 850 arcmin(2) The pixel scale is 0.155 arcsec for 18 mu m pitch, which properly samples the diffraction-limited image at 1.5 mu m. The main program is Ultra Deep Survey (UDS) covering 100 deg(2) down to 28AB mag at least in five broad bands We expect to detect &gt;10(4) galaxies at z=8-9, 10(3)-10(4) galaxies at z=11-12, and 50-100 galaxies at z&gt;14, many of which can be feasible targets for deep spectroscopy with Extremely Large Telescopes. With recurrent deep observations, detection and light curve monitoring for type-Ia SNe in rest-frame infrared wavelength is also conducted, which is another main science goal of the mission. During the in-orbit 5 years observations, we expect to detect and monitor &gt;2000 type-Ia SNe up to z similar to 2. WISH also conducts Ultra Wide Survey, covering 1000deg(2) down to 24-25AB mag as well as Extreme Survey, covering a limited number of fields of view down to 29-30AB mag. We here report the progress of the WISH project including the basic telescope and satellite design as well as the results of the test for a proto-model of the flip-type filter exchanger which works robustly near 100K.
  • Hitoshi Hanami, Tsuyoshi Ishigaki, Naofumi Fujishiro, Kouichiro Nakanishi, Takamitsu Miyaji, Mirko Krumpe, Keiichi Umetsu, Youichi Ohyama, Hyun Jin Shim, Myungshin Im, Hyoung Mok Lee, Myung Gyoon Lee, Stephen Serjeant, Glenn J. White, Christopher N. Willmer, Tomotsugu Goto, Shinki Oyabu, Toshinobu Takagi, Takehiko Wada, Hideo Matsuhara
    PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 64(4) 2011年12月29日  査読有り
    We have studied the star-formation and AGN activity of massive galaxies in the redshift range $z=0.4-2$, which are detected in a deep survey field using the AKARI InfraRed (IR) astronomical satellite and {\em Subaru} telescope toward the North Ecliptic Pole (NEP). The AKARI/IRC Mid-InfraRed (MIR) multiband photometry is used to trace their star-forming activities with the Polycyclic-Aromatic Hydrocarbon (PAH) emissions, which is also used to distinguish star-forming populations from AGN dominated ones and to estimate the Star Formation Rate (SFR) derived from their total emitting IR (TIR) luminosities. In combination with analyses of their stellar components, we have studied the MIR SED features of star-forming and AGN-harboring galaxies.
  • Jongwan Ko, Myungshin Im, Hyung Mok Lee, Myung Gyoon Lee, Seong Jin Kim, Hyunjin Shim, Yiseul Jeon, Ho Seong Hwang, Christopher N. A. Willmer, Matthew A. Malkan, Casey Papovich, Benjamin J. Weiner, Hideo Matsuhara, Shinki Oyabu, Toshinobu Takagi
    ASTROPHYSICAL JOURNAL 745(2) 2011年11月29日  査読有り
    We present the mid-infrared (MIR) properties of galaxies within a supercluster in the North Ecliptic Pole region at z?0.087 observed with the AKARI satellite. We use data from the AKARI NEP-Wide (5.4 deg2) IR survey and the CLusters of galaxies EVoLution studies (CLEVL) mission program. We show that near-IR (3 {\mu}m)-mid- IR (11 {\mu}m) color can be used as an indicator of the specific star formation rate and the presence of intermediate age stellar populations. From the MIR observations, we find that red-sequence galaxies consist not only of passively evolving red early-type galaxies, but also of 1) "weak-SFG" (disk-dominated star-forming galaxies which have star formation rates lower by \sim 4 \times than blue-cloud galaxies), and 2) "intermediate- MXG" (bulge-dominated galaxies showing stronger MIR dust emission than normal red early-type galaxies). Those two populations can be a set of transition galaxies from blue, star-forming, late-type galaxies evolving into red, quiescent, early-type ones. We find that the weak-SFG are predominant at intermediate masses (1010M\odot < M\star < 1010.5M\odot) and are typically found in local densities similar to the outskirts of galaxy clusters. As much as 40% of the supercluster member galaxies in this mass range can be classified as weak-SFGs, but their proportion decreases to < 10% at larger masses (M\star > 1010.5 M\odot) at any galaxy density. The fraction of the intermediate-MXG among red- sequence galaxies at 1010M\odot < M\star < 1011M\odot also decreases as the density and mass increase. In particular, \sim42% of the red-sequence galaxies with early-type morphologies are classified as intermediate-MXG at intermediate densities. These results suggest that the star formation activity is strongly dependent on the stellar mass, but that the morphological transformation is mainly controlled by the environment.
  • Fumihiko Usui, Daisuke Kuroda, Thomas G. Mueller, Sunao Hasegawa, Masateru Ishiguro, Takafumi Ootsubo, Daisuke Ishihara, Hirokazu Kataza, Satoshi Takita, Shinki Oyabu, Munetaka Ueno, Hideo Matsuhara, Takashi Onaka
    PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 63(5) 1117-1138 2011年10月  査読有り
    We present the results of an unbiased asteroid survey in the mid-infrared wavelength region with the Infrared Camera (IRC) on board the Japanese infrared satellite AKARI. About 20% of the point source events recorded in the AKARI All-Sky Survey observations are not used for the IRC Point Source Catalog (IRC-PSC) in its production process because of a lack of multiple detection by position. Asteroids, which are moving objects on the celestial sphere, remain in these "residual events". We identify asteroids out of the residual events by matching them with the positions of known asteroids. For the identified asteroids, we calculate the size and albedo based on the Standard Thermal Model. Finally we have a new brand of asteroid catalog, named the Asteroid Catalog Using AKARI (AcuA), which contains 5120 objects, about twice as many as the IRAS asteroid catalog. The catalog objects comprise 4953 main belt asteroids, 58 near-Earth asteroids, and 109 Jovian Trojan asteroids. The catalog is publicly available via the Internet.
  • K. Enya, T. Kotani, K. Haze, K. Aono, T. Nakagawa, H. Matsuhara, H. Kataza, T. Wada, M. Kawada, K. Fujiwara, M. Mita, S. Takeuchi, K. Komatsu, S. Sakai, H. Uchida, S. Mitani, T. Yamawaki, T. Miyata, S. Sako, T. Nakamura, K. Asano, T. Yamashita, N. Narita, T. Matsuo, M. Tamura, J. Nishikawa, E. Kokubo, Y. Hayano, S. Oya, M. Fukagawa, H. Shibai, N. Baba, N. Murakami, Y. Itoh, M. Honda, B. Okamoto, S. Ida, M. Takami, L. Abe, O. Guyon, P. Bierden, T. Yamamuro
    Advances in Space Research 48(2) 323-333 2011年7月15日  
    We present the SPICA Coronagraphic Instrument (SCI), which has been designed for a concentrated study of extra-solar planets (exoplanets). SPICA mission provides us with a unique opportunity to make high contrast observations because of its large telescope aperture, the simple pupil shape, and the capability for making infrared observations from space. The primary objectives for the SCI are the direct coronagraphic detection and spectroscopy of Jovian exoplanets in infrared, while the monitoring of transiting planets is another important target. The specification and an overview of the design of the instrument are shown. In the SCI, coronagraphic and non-coronagraphic modes are aplicable for both an imaging and a spectroscopy. The core wavelength range and the goal contrast of the coronagraphic mode are 3.5-27 μm, and 10 , respectively. Two complemental designs of binary shaped pupil mask coronagraph are presented. The SCI has capability of simultaneous observations of one target using two channels, a short channel with an InSb detector and a long wavelength channel with a Si:As detector. We also give a report on the current progress in the development of key technologies for the SCI. © 2011 COSPAR. Published by Elsevier Ltd. All rights reserved. 31. -6
  • Fumihiko Usui, Daisuke Kuroda, Thomas G. Mueller, Sunao Hasegawa, Masateru Ishiguro, Takafumi Ootsubo, Daisuke Ishihara, Hirokazu Kataza, Satoshi Takita, Shinki Oyabu, Munetaka Ueno, Hideo Matsuhara, Takashi Onaka
    2011年6月10日  
    We present the results of an unbiased asteroid survey in the mid-infrared wavelength with the Infrared Camera (IRC) onboard the Japanese infrared satellite AKARI. About 20% of the point source events recorded in the AKARI All-Sky Survey observations are not used for the IRC Point Source Catalog (IRC-PSC) in its production process because of the lack of multiple detection by position. Asteroids, which are moving objects on the celestial sphere, remain in these "residual events". We identify asteroids out of the residual events by matching them with the positions of known asteroids. For the identified asteroids, we calculate the size and albedo based on the Standard Thermal Model. Finally we have a brand-new catalog of asteroids, named the Asteroid Catalog Using Akari (AcuA), which contains 5,120 objects, about twice as many as the IRAS asteroid catalog. The catalog objects comprise 4,953 main belt asteroids, 58 near Earth asteroids, and 109 Jovian Trojan asteroids. The catalog will be publicly available via the Internet.
  • Chris Sedgwick, Stephen Serjeant, Chris Pearson, Shuji Matsuura, Mai Shirahata, Shinki Oyabu, Tomotsugu Goto, Hideo Matsuhara, D. L. Clements, Mattia Negrello, Glenn J. White
    2011年6月5日  
    We present a far-infrared galaxy luminosity function for the local universe. We have obtained 389 spectroscopic redshifts for galaxies observed at 90 microns in the AKARI Deep Field South, using the AAOmega fibre spectrograph via optical identifications in the digitized sky survey and 4m-class optical imaging. For the luminosity function presented in this paper, we have used those galaxies which have redshifts 0<z<0.25, have optical magnitudes and are not part of a newly discovered cluster of galaxies (giving a total of 130 sources). Infrared and optical completeness functions were estimated using earlier Spitzer data and APM B-band optical data respectively, and the luminosity function has been prepared using the 1/Vmax method. We also separate the luminosity function between galaxies which show evidence of predominantly star-forming activity and predominantly active galactic nucleus (AGN) activity in their optical spectra. Our luminosity function is in good agreement with the previous 90 micron luminosity function from the European Large Area ISO Survey, and we also present a luminosity function with combined AKARI and ISO data. The result is in reasonable agreement with predictions based on the earlier IRAS 60 micron PSC-z catalogue, and with a recent backward evolution model.
  • Ko Arimatsu, Takashi Onaka, Itsuki Sakon, Shinki Oyabu, Yoshifusa Ita, Toshihiko Tanabé, Daisuke Kato, Fumi Egusa, Takehiko Wada, Hideo Matsuhara
    PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC 123(906) 981-995 2011年5月28日  査読有り
    Mid-infrared images frequently suffer artifacts and extended point spread functions (PSFs). We investigate the characteristics of the artifacts and the PSFs in images obtained with the Infrared Camera (IRC) onboard AKARI at four mid-infrared bands of the S7 (7{\mu}m), S11 (11{\mu}m), L15 (15{\mu}m), and L24 (24 {\mu}m). Removal of the artifacts significantly improves the reliability of the ref- erence data for flat-fielding at the L15 and L24 bands. A set of models of the IRC PSFs is also constructed from on-orbit data. These PSFs have extended components that come from diffraction and scattering within the detector arrays. We estimate the aperture correction factors for point sources and the surface brightness correction factors for diffuse sources. We conclude that the surface brightness correction factors range from 0.95 to 0.8, taking account of the extended component of the PSFs. To correct for the extended PSF effects for the study of faint structures, we also develop an image reconstruction method, which consists of the deconvolution with the PSF and the convolution with an appropriate Gaussian. The appropriate removal of the artifacts, improved flat-fielding, and image reconstruction with the extended PSFs enable us to investigate de- tailed structures of extended sources in IRC mid-infrared images.
  • Kamenetzky, J., Glenn, J., Maloney, P. R., Aguirre, J. E., Bock, J. J., Bradford, C. M., Earle, L., Inami, H., Matsuhara, H., Murphy, E. J., Naylor, B. J., Nguyen, H. T., Zmuidzinas, J.
    The Astrophysical Journal 731(2) 2011年4月  査読有り
    We present a 190-307 GHz broadband spectrum obtained with Z-Spec of NGC 1068 with new measurements of molecular rotational transitions. After combining our measurements with those previously published and considering the specific geometry of this Seyfert 2 galaxy, we conduct a multi-species Bayesian likelihood analysis of the density, temperature, and relative molecular abundances of HCN, HNC, CS, and HCO+. We find that these molecules trace warm (T&gt;100 K) gas of H2 number densities 104.2-104.9 cm-3. Our models also place strong constraints on the column densities and relative abundances of these molecules, as well as on the total mass in the circumnuclear disk. Using the uniform calibration afforded by the broad Z-Spec bandpass, we compare our line ratios to X-ray-dominated region (XDR) and photon-dominated region models. The majority of our line ratios are consistent with the XDR models at the densities indicated by the likelihood analysis, lending substantial support to the emerging interpretation that the energetics in the circumnuclear disk of NGC 1068 are dominated by accretion onto an active galactic nucleus....
  • Kentaro Aoki, Shinki Oyabu, Jay P. Dunn, Nahum Arav, Doug Edmonds, Kirk T. Korista, Hideo Matsuhara, Yoshiki Toba
    2011年1月23日  
    We present Subaru observations of the newly discovered luminous quasar AKARI J1757+5907, which shows an absorption outflow in its spectrum. The absorption consists of 9 distinct troughs, and our analysis focuses on the troughs at ~ -1000$ km s^{-1} for which we can measure accurate column densities of He I*, Fe II and Mg II. We use photoionization models to constrain the ionization parameter, total hydrogen column density, and the number density of the outflowing gas. These constraints yield lower limits for the distance, mass flow rate and kinetic luminosity for the outflow of 3.7 kpc, 70 M_{sun} yr^{-1}, and 2.0 x 10^{43} ergs s^{-1}, respectively. Such mass flow rate value can contribute significantly to the metal enrichment of the intra-cluster medium. We find that this moderate velocity outflow is similar to those recently discovered in massive post-starburst galaxies. Finally, we describe the scientific potential of future observations targeting this object.
  • S. Oyabu, D. Ishihara, M. Malkan, H. Matsuhara, T. Wada, T. Nakagawa, Y. Ohyama, Y. Toba, T. Onaka, S. Takita, H. Kataza, I. Yamamura, M. Shirahata
    Astronomy and Astrophysics 529 2011年  
    Aims. We present a new sample of active galactic nuclei (AGNs) identified using the catalog of the AKARI Mid-infrared (MIR) All-Sky Survey. Our MIR search has the advantage of detecting AGNs that are obscured at optical wavelengths by extinction. Methods. We first selected AKARI 9 μm excess sources with F(9 μm)/F(K ) > 2 where K magnitudes were taken from the Two Micron All Sky Survey. We then obtained follow-up near-infrared spectroscopy with the AKARI/IRC to confirm that the excess is caused by hot dust. We also obtained optical spectroscopy with the Kast Double Spectrograph on the Shane 3-m telescope at Lick Observatory. Results. On the basis of these observations, we detected hot dust with a characteristic temperature of ≳ 500 K in two luminous infrared galaxies. The hot dust is suspected to be associated with AGNs that exhibit their nonstellar activity not in the optical, but in the near- and mid-infrared bands, i.e., they harbor buried AGNs. The host galaxy stellar masses of ∼4-6 × 10 M are small compared with the hosts in optically-selected AGN populations. These objects were missed by previous surveys, demonstrating the power of the AKARI MIR All-Sky Survey to widen AGN searches to include more heavily obscured objects. The existence of multiple dusty star clusters with massive stars cannot be completely ruled out with our current data. © 2011 ESO. S S · 9

MISC

 241
  • 瀧本幸司, 佐野圭, 當銘優斗, 川崎悠貴, 中川俊輔, AREDA Eyoas Ergetu, FIELDING Ezra, CHATAR Keenan Alexsei Aamir, 松浦周二, 廣瀬優樹, 小鹿哲雅, 津本明音, 津村耕司, 中川貴雄, 松原英雄, 磯部直樹, 榎木谷海, 田中颯, 高橋葵
    日本天文学会年会講演予稿集 2023 2023年  
  • 佐野圭, 趙孟佑, 北村健太郎, 寺本万里子, 増井博一, 布施哲人, 瀧本幸司, 山内貴志, 中山大輔, OERGER Necmi Cihan, CORDOVA-ALARCON Jose Rodrigo, SCHULZ Victor Hugo, OFOSU Joseph, 中川貴雄, 松原英雄, 磯部直樹, 宮崎康行, 平子敬一, 船瀬龍, 松浦周二, 和田武彦, 津村耕司, 高橋葵, 五十里哲, 谷津陽一, 軸屋一郎, 青柳賢英
    日本天文学会年会講演予稿集 2023 2023年  
  • 瀧本幸司, 佐野圭, 松浦周二, 津村耕司, 中川貴雄, 松原英雄, 磯部直樹, 和田武彦, 高橋葵, 布施哲人, 趙孟佑, 北村健太郎, 増井博一, 寺本万里子, NECMI Oerger, RODRIGO Cordova-Alarcon Jose, VICTOR Schulz, JOSEPH Ofosu, 宮崎康行, 船瀬龍, 五十里哲, 青柳賢英, 谷津陽一, 軸屋一郎
    日本天文学会年会講演予稿集 2023 2023年  
  • 和田武彦, 金田英宏, 金田英宏, 石原大助, 長勢晃一, 内山瑞穂, 伊藤哲司, 國生拓摩, 平原靖大, 土川拓朗, 前嶋宏志, 前嶋宏志, 大西崇介, 大西崇介, 松本光生, 松本光生, HUANG Ting-Chi, HUANG Ting-Chi, 榎木谷海, 榎木谷海, 海老原大路, 海老原大路, 笠羽康正, 坂野井健, 大薮進喜, 鈴木仁研, 中川貴雄, 松原英雄, 山岸光義, WANG Shiang-Yu, 大山陽一
    日本天文学会年会講演予稿集 2021 2021年  
  • 山村一誠, 金田英宏, 小川博之, 中川貴雄, 松原英雄, 山田亨, 鈴木仁研, 尾中敬, 河野孝太郎
    日本天文学会年会講演予稿集 2021 2021年  

書籍等出版物

 6

講演・口頭発表等

 1

主要な担当経験のある科目(授業)

 5
  • 2011年4月 - 現在
    宇宙科学II  (東京大学(前期課程))

主要な共同研究・競争的資金等の研究課題

 41