すばるユーザーズミーティング2011年度 Abstracts


[[Poster]]


Chisato Yamauchi (NAOJ)
(Title) SMOKAの現状報告
(Abstract) SMOKAは、すばる望遠鏡、岡山天体物理観測所188cm望遠鏡、東京大学木曽観測所105cmシュミット望遠鏡、MITSuME、東広島天文台かなた望遠鏡のデータをアーカイブしている公開サービスです。現状を報告します。



Ikuru Iwata (NAOJ)
(Title) MOIRCS Upgrade Project
(Abstract) We are developing a MOIRCS upgrade project named 'nuMOIRCS'. In this project we aim to upgrade detectors from HAWAII-2 to H2RG which should significantly reduce the read-out time, as well as to install new integral field units on the focal plane. The IFU should enable us to explore the internal kinematics of distant galaxies, which is a key to understand how the morphologies of various galaxies in today's universe have been formed. In this contribution we will describe the scientific objectives of this project, the current development status and the expected schedule.



Masafumi Yagi (NAOJ)
(Title) Crosstalk in Suprime-Cam
(Abstract) An idea for estimating the crosstalk coefficient is given. The application of the method for Suprime-Cam data will be presented.



Shinobu Ozaki (NAOJ)
(Title) Development of FOCAS IFU
(Abstract) We are developing an integral field unit with an image slicer for the existing optical spectrograph FOCAS on Subaru telescope. Basic optical design has already finished. The slice width is 0.4 arcsec, the slice number is 24, and the field of view is 13.5 x 9.6 arcsec^2. We will report current status of this project.



Masahide Hidai (Tokai Univ.)
(Title) Chromospheres in Metal-Poor Stars Evidenced from the He I 10830 A Line
(Abstract) Based on the near-IR spectra of late-type stars in a wide range of metallicity observed with IRCS+AO188, we found that He I 10830 A line appears in absorption in almost all moderately to extremely metal-poor stars.



Kentaro Aoki (NAOJ)
(Title) Quasars are not in cluster of galaxies, but in group of galaxies
(Abstract) We have performed Suprime-Cam multi-band imaging of high redshift cluster of galaxies candidates identified by Mg II absorption lines. Our cluster candidates were selected by Mg II absorption lines which are more than 1000 km s$^{-1}$ redshifted from the background quasar. The service observation has been done for two quasars (z=0.915 & 1.18) with r', i', z'-bands. The seeing was good (0.6"-0.8"). The two candidates were most promissing ones, however, we could not any signs of cluster of galaxies. The large velocity without cluster's signature suggests they may be the ancestor of 'fossil group'.
Additionaly, and more interestingly, we discovered the two targeted quasars mentioned above and another quasar (z=0.739) in the group of galaxies. There are 3-4 galaxies within 50 kpc form the quasar, and quasars and galaxies have signs of interactions. The z=0.739 quasar does not show Mg II absorption lines. We will compare other quasar imagings and discuss the implications.



Ken Mawatari (Tohoku Univ.)
(Title) CHARACTERIZATION OF THE DISTRIBUTION OF THE Lya EMITTERS IN THE 53W002 FIELD AT z = 2.4
(Abstract) We present the results of the wide-fi eld (31'x 24') narrow band (custom-made NB413) imaging of the field around the radio galaxy 53W002 (the 53W002 fi eld) with Subaru/Suprime-Cam. We detected the 204 Lyα emitters (LAEs) at z = 2.4 down to 26 AB mag (NB413) with the rest frame equivalent width (EW) larger than 25 Å. We also detected the 4 Lyα blobs (LABs). The entire LAE population in the 53W002 field have the number density, EW and size distributions similar to those of other fields at z 〜 2. We identify the signi cant high density region (53W002F-HDR) that spreads over 〜 5'x 4' and have the LAE number density of nearly four times as dense as the average of the entire field, while only a fraction of the objects detected by the previous medium-band survey was proved to be at z = 2.4. Using the probability distribution function (PDF) of mass fluctuation we evaluate its rareness probability, and fi nd that 53W002F-HDR is the moderately rich structure with the rareness probability of 0.9 %. The distributions of the Lyα EW and luminosity in the 53W002 field show no notable environmental dependency at the scale of 10 Mpc, which is also con rmed by using the data of the other fields. By contrast, the four LABs are all found to be located in the rims of high density regions.



Atsushi Nishizawa (IPMU)
(Title) Formulation and measurement of the galaxy bias based on the renormalized Standard Perturbation Theory
(Abstract) A galaxy bias is a well known source of uncertainty on the measurement of the perturbation of matter by means of illuminating galaxy. For precise measurement, for example, of power spectrum, the constant galaxy bias no longer holds especially on scales k > 0.1 h/Mpc. We propose the new model that the scale and mass dependency of the galaxy bias beyond k ~ 0.1 h/Mpc agrees well with the N-body simulation and also propose the way of measure the galaxy bias by combining a galaxy redshift survey like Prime Focus Spectrograph and a deep galaxy lensing survey like Hyper Suprime Cam.



Tsuyoshi Terai (NAOJ)
(Title) High-Precision Measurements for Brightness Variation of NII Nereid
(Abstract) Nereid, the second largest Neptune's satellite, has an irregular prograde orbit. It is still unknown whether it formed in the circum-planetary disk or was captured from a heliocentric orbit. We measured the brightness variations of Nereid due to its rotation and the opposition effect using Subaru+Suprime-Cam. The obtained rotation period and phase coefficient indicate that Nereid originates an external body captured by Neptune in the early Solar system.



Mariko Kubo (Tohoku Univ.)
(Title) The star formation in the SSA22 protocluster at z=3.09
(Abstract) The SSA22 protocluster at z = 3.09 is known to be one of the most outstanding structure at high redshift. We have conducted the MOIRCS JHK deep imaging and selected the protocluster candidate from the photometric redshift. There are density excess of the MOIRCS K-selected galaxies. Therefore we analysed the star formation properties of them. First, there are density excess of the Spitzer MIPS 24um detected IR luminous galaxies which have star formation rate over 1000Msolar/yr. On the other hand, we found the density excess of the passively evoving galaxies from their rest-UV to NIR color. These galaxies are concentrated around the density peak of the LAEs at z=3.09, supporting the rapid formation of the massive galaxies at the density peak predicted from the hierarchical formaiton scenario in ΛCDM universe.



Takashi Ito (NAOJ)
(Title) Asymmetric cratering on the Moon from the revised NEA model and its implication
(Abstract) Recent lunar crater counting studies have revealed an asymmetric distribution of rayed craters on the lunar surface. The asymmetry is related to the synchronous rotation of the Moon, and there is a higher density of rayed craters on the leading hemisphere compared with the trailing hemisphere. Here we report the progress in our study to test the hypotheses that (i) the population of near-Earth asteroids is the source of the impactors that have made the rayed craters, and (ii) that impacts by this projectile population account quantitatively for the observed asymmetry. We carried out numerical simulations of the orbital evolution of a large number of test particles representing near-Earth asteroids in order to determine directly their impact flux on the Moon. In a previous study, we reported results based on the debiased NEA model of Bottke+ (2002), where we found that the theoretical model yields a smaller asymmetry than is observed on the Moon. A possible reason for the discrepancy is that the population of NEAs having low relative velocity with respect to the Earth-Moon system is underestimated in the debiased NEA model. In the present work, we report results based on a second and independent debiased NEA model, and we compare these with our previous study. Our results provide possible constraints on the dynamical characteristics of the near-Earth asteroid population and may help to improve theoretical models of this population. This kind of hidden population might be detected by future large-scale surveys such as the HSC Solar System Survey.



Masaru Kajisawa (Ehime Univ.)
(Title) Stellar Mass Growth of Galaxies since z~3 in MODS
(Abstract) We present results on the evolution of galaxy stellar mass at 1<~z<~3 from MOIRCS Deep Survey, which is a deep NIR imaging survey with Subaru/MOIRCS in the GOODS-North region.
We had found that the low-mass slope of the galaxy stellar mass function becomes steeper with redshift and the number density evolution of ~M* galaxies at z>1 is stronger than low-mass galaxies. We investigated the stellar mass function for passive and star-forming galaxies separately, and found that the strong evolution of ~M* galaxies is due to a rapid increase of the number of passive galaxies. We also studied star formation rates of galaxies as a function of mass at that epoch to discuss how the stellar mass growth of galaxies proceeded in the important era.



Takahiro Iino (Nagoya Univ.)
(Title) Atmospheric evolution of giant planet : cometary impact as the sources of minor gases
(Abstract) Collisionally produced gases in the atmosphere of giant planets have key informations to reveal the distribution of comet and dust grain in outer solar system, and also to imply atmospheric composition of exoplanets. In contrary to earth-like planets, the atmospheric composition of giant planets have been thought to be very static. From observational result, a collision of comet Shoemaker-Levy/9 on Jupiter in 1994 had produced large amount of short-lifetime gases such as CO, HCN, CS and so on. Similar supplying process is predicted to be existed in Neptune
because CO and HCN exist with high mixing ratio. In this presentation, I am presenting our observational results using ASTE and 45m telescope of NAOJ toward Neptune and Jupiter to constrain such supplying system in Neptune and implications to the composition of exoplanet's atmosphere.



Fumi Yoshida (NAOJ)
(Title) Slitless Spectroscopy of Small Solar System Bodies on a Dark Cloud Curtain
(Abstract) We carried out a slitless spectroscopy twice (2009 May and 2010 June) by using grism filters which was equipped to the prime focus camera (Suprime-Cam) of the 8.2 m Subaru telescope. We obtained the low dispersion spectra of 50 small solar system bodies (R<~23 mag). These are the first spectroscopic surveys for such faint moving objects in the main belt region. We found many Q-type candidates in the main belt region, though very few Q-types have been discovered before. This means that the Q-type has size dependency and there must be a certain number of Q-types in small MBAs.



Eric Jeschke (NAOJ)
(Title) The Gen2 Observation Control System: What's New 2012
(Abstract) We present the developments of the past year in the new Subaru Telescope Observation Control System.



Chikako Yasui (NAOJ)
(Title) ALMA Cycle 1 2012
(Abstract) Atacama Large Millimeter-submillimeter Array (ALMA) Early Science Cycle 1will start scientific observation in 2012 and provide unprecedented power to resolve many issues of astrophysics, e.g., planetary science. Its high spacial resolution (~0.1 arcsec ~1.4 AU at the distance of Taurus in the cycle 1 phase) and extreme sensitivity of ALMA covering frequency ranges of 30-900 GHz will tell us physical properties of protoplanetary disks and proto-planets, that can be compared directly with theoretical predictions. ALMA can also investigate planetary atmosphere in the submm wavelength diagnosing molecular abundance, temperature and kinematics of many species with high precision. The East-Asian ALMA Regional Center (EA-ARC) will provide user support in many aspects. We present the latest status and information for the observing proposal of ALMA.