The 21-cm hyperfine line of neutral hydrogen from the high-redshift Universe (6 < z 20) promises to probe a new era in cosmology, the epoch of reionization (EoR). It will provide more detailed, less ambiguous and more complete three-dimensional informations than other observations of the EoR (such as the QSO absorption lines, or the secondary scattering of CMB). It also traces many different physical processes. The next generation radio telescopes, SKA and its precursors, will start to operate within one decade, and will observe this signal. Numerical simulations predicting the 21-cm emission are important to optimize the design of the instruments, and interpret the observations. In this work, we develop a continuum radiative transfer part for the LICORICE cosmological code to study the epoch of reionization, where radiative transfer is an essential tool. We use a Monte-Carlo ray-tracing algorithm on an adaptive grid. Several tests, both for static density field cases and radiative hydrodynamic cases have been performed to validate the code. Then we compute the 21-cm signal during the EoR, which provides a direct probe on reionization and contains a lot of informations on the sources of ionization and heating.

A number of physical phenomena are predicted to operate in astrophysical settings theoretically and may be crucial for understanding the nature of astrophysical objects. Magnetorotational instability (MRI) and magnetic dynamos are examples of such processes believed to be the key to the origin and growth of magnetic fields in galaxies, accretion flows, stars, planets and Universe as a whole. Although firmly predicted and verified in theory, MRI has not been robustly reproduced in a physical laboratory here on Earth. Recently, we discovered and successfully observed the analogue of MRI in a Couette-Taylor Flow of Polymer Fluids. A limited cases of a constrained dynamo have been reproduced in Riga and Karlsruhe experiments. There are a number of groups working and building laboratory experiments to verify and study MRI and dynamos. I will review the progress made in these experiments, including works that I have been involved with.

During the past decade, astronomy has undergone a period of rapid growth in Taiwan. A number of groups have been established at the universities as well as at the Academia Sinica. We will review the current progress on a number of projects including SMA, AMiBA, TAOS, CFHT/WIRCam, ALMA, and Subaru/HSC.

In this presentation, I will be talking about the optical designs and analyses of the WFMOS high-resolution spectrograph(HRS). WFMOS HRS is the next generation instrument of the Gemini/Subaru consortium that aims to conduct spectroscopic studies of the formation and evolution of the Galaxy, the study often termed as \\\"Galactic Archaeology Survey\\\". Consisting of twin (or quadruple) spectrographs, HRS is to be fed by 1500 fiber optics distributed over the field of view (1.5 degrees in diameter) of the HyperSuprime Camera (HSC) on the 8m Subaru telescope. The wavelength coverage is from 420nm to 900nm. Following a brief introduction to the main science objectives of the HRS instrument, the presentation will discuss issues involved in the choice of diffraction gratings, camera optics, and collimator designs as well as trade-off study results in terms of system throughput and image quality. Current status and future prospect of the project will also be covered.

The supermassive star, Eta Carinae, has attracted people\\/s attention with its picturesque bipolar nebula structure seen in Hubble space telescope images. The bipolar nebula was produced through an enormous outburst in 1840\\/s when Eta Carinae became the 2nd brightest star in the sky. This event, which ejected more than ~10 Msolar, was a signature of large-scale, unstable mass loss episodes at the end of a massive star\\/s life. With the advent of space telescopes, Eta Carinae has been observed in great detail. However, direct emission from the central star has never been detected, because it is heavily shrouded by the bipolar nebula. Emission from the central region indicates that Eta Carinae houses a binary system with a highly eccentric 5.5 year orbit, which perhaps comprises an evolved star with ~90 Msolar and a (possibly) a near-main-sequence O star with ~30 Msolar. Among multi-wavelength observations, X-ray emission varied dramatically with the orbital period, showing a flux increase around the periastron passage followed by a strong flux drop by a factor of 100 for three months thereafter. The flux variation is basically explained by thin-thermal plasma emission produced by the collision of winds from the two stars (wind-wind collision: WWC), but the cause of the flux drop is controversial. The two leading hypotheses are an \\\"eclipse\\\" of X-ray plasma by the thick primary stellar wind or a collapse of the WWC plasma. Resolving this problem is important for solving the process of mass loss from massive stars, and in finding the property of the component stars. We present the latest view of this enigmatic object, focusing on the X-ray observations around the last periastron passage in 2003. We also introduce upcoming campaign observations of Eta Carinae around the next periastron passage in early 2009.

In this talk, we would like to introduce how to describe wave turbulence for nonlinearly and wealky interacting despersive wave ensemble such as Hasselmann\\/s approach, smooth cumulant method, random phase approximation, and random phase and amplitude formalism which has been developed most lately. And we also introduce recent development in wave turbulence theory and application to Alfven wave.

CoRoT is a 27cm space telescope in a polar orbit that is capable of making ultra-precise photometric measurements of stars continuously for up to a maximum of 150 days. It has a dual purpose: asteroseismology of up to 10 bright (V=5-9 mag) stars and the photometric detection of transiting planets for 12.000 fainter stars (V=11-16 mag). It is the first space mission dedicated to the detection of extrasolar planets. It was successfully launched on 27 December 2006 and the telescope is working perfectly. Since launch CoRoT has been steadily returning light curves of unprecendented quality. I will give an overview of the current status of the mission and present some recent results, mostly highlighting the exoplanet discoveries. I will also for present results from addtional science conducted from the so-called exofield of CoRoT.

옛날 사람들은 물의 흐름을 이용하여 시간을 쟀는데 이것이 물시계의 시초다. 물시계는 해시계와 더불어 사용되었지만, 밤낮으로 시간을 알아내는 데는 물시계가 더 쓸모가 있어 동아시아를 비롯한 대부분의 문화권에서는 표준시계로 사용되었다. 조선 세종은 위정자의 임무의 하나인 관상수시를 제대로 실현하기 위해 조선의 실정에 맞는 수시(授時)제도를 갖추도록 여러 가지 정책을 세우고 구체적인 사업에 착수하였다. 그리고 그와 아울러 천문관측의 필요성을 느껴 그 일환으로 간의대를 만들고, 간의와 규표, 시보를 위한 보루각, 해시계 등의 여러 천문기구들을 제작, 설치하였다. 그 중의 하나가 자격루이다. 자격루는 물시계 시스템을 비롯하여 아날로그/디지털 변환기(방목-동판), 에너지 증폭기구(철환방출기구), 12시 시보장치(時機), 경점 시보장치(更點機) 등으로 이루어진 복합 시스템이다. 동아시아 전통의 3단 유입식(流入式) 물시계 기술과, 13세기 아랍에서 제작된 시계에서 아이디어를 얻은 시보장치의 기술, 그리고 한국 전래 기술의 융합으로 탄생된 자격루는 우리 풍토와 전통을 대변하는 한국성(韓國性)과 아울러 세계로 열린 보편성을 지닌 창의적인 발명품이다. 그러나 이렇게우리 역사는 물론, 15세기 동아시아 시계기술사, 오토메이션(자동화)과 로보틱스 역사의 한 장을 장식한 자격루이지만, 아쉽게도 1866년 병인양요의 와중에 소실되어 자격루 설계도는 전해오지 못하게 되었다. 지난 30년 동안 우리의 얼굴인 만 원권 지폐 속에 살아온 ‘물시계’는 세종 자격루의 후신이다. 이「보루각기」속의 자격루가 573년 만에 그 진면목을 우리 앞에 드러냈고, 연구를 시작한지 23년이라는 기나 긴 여정을 거친 후인 지난 2007년 11월말에 복원되었다. 이번 발표에서는 세종시대의 왕성했던 의표사업과 아울러 새로 복원한 자격루의 시스템과 복원과정을 설명하면서 한국의 전통과학기구들을 살펴보고자 한다.

If ultrahigh energy cosmic rays (UHECRs) originate from extragalactic sources, understanding the propagation of the charged particles through the magnetized large scale structure (LSS) of the universe is crucial in the search for astrophysical accelerators. Adopting a novel model based on turbulent dynamo, the strength of the intergalactic magnetic field is estimated from local dynamic properties of the gas flows in hydrodynamic simulations of a concordance LCDM universe. With the model magnetic field, the deflection angle and time delay are calculated for protons with $E > 10^{19}$ eV propagating through the large scale structure of the universe, as well as the energy loss due to interactions with cosmic background radiation. Implications of this study on the origin of UHECRs will be discussed.

Metal-poor stars in our Galaxy are the best preserved fossils of the formation history of Our Galaxy. Especially, chemical composition of them provides important clues to understanding the early stage of the chemical evolution of the Galaxy. Recently, our knowledge of the Galactic formation improved based on kinematic and chemical information of the halo stellar component. I\\/ll talk on the recent interesting results including our results from BOES data. Add to that I\\/ll briefly introduce surveys such as Skymapper, SEGUE, LAMOST and HERMES.

I will present a summary of recent results from the Spitzer Legacy science program, the Formation and Evolution of Planetary Systems (FEPS, http://feps.as.arizona.edu). FEPS program samples 328 sun-like systems (0.7 Msun - 2.2 Msun) in age ranging from 3 Myr to 3 Gyr. We trace the evolution of circumstellar dust from primordial planet-building stages in young circumstellar disks through to older collisionally generated debris disks. Our goal is to help define the timescales over which terrestrial and gas giant planets are built, constrain the frequency of planetesimal collisions as a function of time, and establish the diversity of mature planetary architectures. The FEPS team has obtained spectro-photometric observations for all our sample stars using all three science instruments (IRAC, IRS, MIPS) aboard the Spitzer Space Telescope from 3.6 micron to 70 micron. I will review recent FEPS results including: 1) complete census of 70 micron-bright debris disks; 2) constraints on dissipation of primordial disks in terrestrial planet zones around stars younger than 30 Myr; and 3) properties and evolution of circumstellar dust around 314 solar-type stars.

Massive stars are fundamental in determining the appearance and evolution of galaxies. For studying the Galactic rotation curve and earlier phase of massive star forming process, three massive star forming regions are selected. The Galactic rotation curve can be constrained with the rotation speed of stars and gas because massive stars and their associated molecular clouds trace the spiral arms of The Galaxy. I will introduce the VERA system and the results of the first astrometric observations toward three massive star forming regions. And, by using the results of the measurements of parallaxes and proper motions, constrain the rotation curve of outer galactic plane and discuss about earlier phase of stellar evolution in massive star forming regions.

NGC 5044 Group is one of the brightest Galaxy Groups in X-rays. Due to its proximity (redshift=0.0087), it has been studied extensively in X-rays and in other wavebands. To trace the Dark Matter (DM) Profile of this interesting group down to the core, the high-resolution Chandra data had been used. However, its field-of-view is limited to the central region (r<100 kpc). To better constrain the DM profile from the core up to a radius of 250 kpc, a Chandra-ROSAT simultaneous analysis had been performed. Within 250 kpc, the total mass is found to be ~1.6 x 1013 solar mass, 12% of which comes from baryons (gas and stars) while 88% presumably comes from dark matter. Within the inner central regions, the total mass profile exhibits a double structure, typical for groups containing a central Dominant (cD) galaxy. The onset of this double structure seems to signify likely interface between stellar-dominated and DM-dominated regimes. For NGC 5044, this interface occur around 7.5 kpc. Beyond this radius, DM dominates the total mass. The DM profile is reasonably fitted with the popular NFW model yielding results consistent with observed scatter expected for Cold Dark Matter (CDM) halos. A Power-law fit to the DM profile gives α=1.88+0.32. This slope is within the observed range, but is significantly larger than that of Low Surface Brightness (LSB) galaxies and self-interacting DM halos.

The US National Space Weather Program (NSWP) refers “Space Weather” to “conditions on the Sun and in the solar wind, magnetosphere, ionosphere, and thermosphere that can influence the performance and reliability of space-borne and ground-based technological systems and can endanger human life or health.” One of the basic research areas that were specified to have significant gaps in our present understanding and represent particular challenges in achieving Space Weather goals is forecast of the evolution of ionospheric irregularities. The nighttime electron density irregularities in the low-latitude F region cause the most severe radio scintillation affecting the satellite communication and navigation systems. Understanding of the onset conditions of the irregularities and forecasting of this phenomenon have been the top research priority since its discovery. While the electron density irregularities are known to be produced by the Rayleigh-Taylor instability, the day-to-day variability of their occurrence and dependence on the longitude, season, solar cycle, and magnetic activity were not yet clearly understood. In this talk, we will overview the characteristics of the low-latitude ionospheric turbulence and discuss the recent progresses and future work.

In this talk, we review the three-dimensional evolution of the solar wind density and speed distributions in the inner heliosphere. The primary solar wind data used in this study has been obtained from the interplanetary scintillation (IPS) measurements made at the Ooty Radio Telescope, which is capable of measuring scintillation of a large number of radio sources per day and solar wind estimates along different cuts of the heliosphere, allow to image the three-dimensional structure of the ambient solar wind and propagating transients (CMEs or CIRs) in the Sun-Earth distance range. Results indicate that (1) the interaction between the CME (or the CIR) and the background solar wind determines the radial evolution of its speed and size, (2) the magnetic energy associated with the propagating transient (the magnetic cloud in the case of a CME and the high-speed stream for a CIR) is likely to play a crucial role in determining the effectiveness of the compression and propagation characteristics of the disturbance. Ooty studies play a key role in quantifying the drag force imposed on disturbances by the solar wind interaction, which is essential in modeling the propagation characteristics of disturbances within 1-AU heliosphere. Such studies also have a great importance in understanding the prediction of CME/CIR-associated space weather at near-Earth space.

The observational studies of high redshift universe seem dominated by large telescopes, but small telescopes (1-2 m class telescopes) are still making important contributions to understand the high redshift universe, out to z ~ 6. I will review our observational studies of high redshift universe using 1-2m class telescopes such as the KASI\/s Mt. Lemmon 1-m telescope, Bohyunsan Observatory\/s 1.8-m telescope, the Maidanak observatory\/s 1.5-m telescope, and the 68cm AKARI space telescope. The studies carried out with these telescopes cover various topics such as the gamma-ray burst afterglow, bright quasars, star-forming galaxies and AGNs, and high redshift quasars. Along with these findings, I will present exclusive photos of the passage to the Uzbekistan\/s Maidanak observatory.

Radio galaxies continue to play an important role in cosmological debates. They are hosted by massive elliptical galaxies, and their high luminosities allow them to be detected across a large range in redshift. In this colloquium I will describe results from an investigation into the properties of the warm ionized gas in the interstellar medium of radio galaxies at high-z (z>2). We find evidence that this warm ionized gas is in infall towards the AGN or host galaxy. Some implications will be discussed.

Results based on a systematic analysis of the durations for Swift gamma-ray bursts (GRBs) are gotten and compared with those of pre-Swift data. For 95 GRBs with known redshift, we show that the observed durations have two log-normal distributions that are clearly divided at 2 seconds. This is consistent with the earlier BATSE results. The intrinsic durations also show a bimodal distribution but shift systematically towards the smaller value compared with the observed one. We find that the intrinsic distributions of long GRBs obtained with Swift and pre-Swift (or BATSE) are significantly different, particularly in the distribution centers. Our present study confirms the spectra of short GRBs are in general harder than the long GRBs and shows that this trend becomes weak in the source frame.

현재 건국대학교의 R&D 추진 조직에 대한 설명과 대학이 추진 및 진행 중인 산학연 협력R&D의 방향과 미래계획 등에 대해 설명하고 건국대학교와 한국천문연구원 간에 상호협력 할 수 있는 세부분야에 대한 계획 등을 제안한다.

It has long been known that our universe is expanding, but recent Type Ia supernovae observations have demonstrated that the expansion is accelerating. Current cosmological models attribute this acceleration to a form of repulsive “dark energy”. The simplest explanation of dark energy is Einstein’s cosmological constant found in his original field equations; more exotic alternatives would demand radically new physics. In this talk, I will describe the largest ever galaxy survey undertaken of the distant universe that utilizes the baryon acoustic oscillation (BAO) signature seen in the clustering of galaxies to precisely measure the dark energy equation of state and hence test whether dark energy can be described by Einstein’s cosmological constant model. Called the “WiggleZ” survey, it is using the powerful two degree field multi-object spectrograph AAOmega on the 3.9m Anglo-Australian Telescope to obtain spectra and measure redshifts for up to 500,000 galaxies in the range 0.5