The cumulative distribution of stellar ages showed a distinct difference among star forming regions in NGC 2264. A Kolmogorov-Smirnov test gave a very low probability of them being from the same population. The results indicate that star formation in NGC 2264 started at the surface region (Halo and Field regions) about 6 -- 7 Myr ago, propagated into the molecular cloud and finally triggered the recent star formation in the Spokes cluster. The kind of sequential star formation that started in the low-density surface region (Halo and Field regions) implies that star formation in NGC 2264 was triggered by an external source.

KAIST Institute of Optical Science & Technology (KIOST)는 3년 전 KAIST 내의 융합연구의 실험을 위해 설립된 8개의 연구소 중의 하나이다. 설립의 취지는 최근에 많은 중요성이 부각되고 있는 펨토초 레이저를 중심으로 초고속 광학의 학제간의 연구와 실용화에 중점을 두고 있다. 참여하고 있는 학과로는 물리학과, 기계공학과, 화학과, 전자공학과, 그리고 생명공학과로 대표되며, 15명의 교수와 60 여명의 대학원생이 함께 일하고 있다. 본 연구소의 특징은 서로 다른 학문분야의 전문 가들이 초고속 광학에 공동 관심을 갖고, 새로운 융합연구의 주제의 발굴과 이의 구체화를 위해 노력하고 있다. 주요 연구분야는 펨토초 레이저 광원의 개발, 아토초 과학분야의 기본 연구, 시간 과 거리측정의 새로운 표준과 방법 개발, 생체와 의공학분야에의 응용 그리고 초정밀 레이저 가 공기술을 들 수 있다. 이번 강연에서는 학문적으로 매우 거리가 먼 연구집단들이 하나의 주요 공 통 관심사를 통해 함께 모여 파급효과가 큰 융합연구를 진행하고 있는 구체적인 사례를 발표하고 이에 대한 여러 의견을 교환하는데 주요 목적을 두고자 한다.

We present new measurements of the coherent motion of galaxies based on observations of the large-scale redshift--space distortions seen in the two--dimensional two--point correlation function of Luminous Red Galaxies in Data Release Seven of the Sloan Digital Sky Survey. We have developed a new methodology for estimating these coherent motions, which is less dependent on the details of galaxy bias and of the cosmological model to explain the late--time acceleration of the expansion of the Universe. We measure a one--dimensional velocity dispersion of galaxies on large--scales of sigma_v=3.01^{+0.45}_{-0.46} Mpc/h and sigma_v=3.69^{+0.47}_{-0.47} Mpc/h at a mean redshift of z=0.25 and 0.38 respectively. These values are fully consistent with predictions for a WMAP7--normalised LCDM Universe and inconsistent (at >5 sigma) with a Dvali-Gabadadze-Porrati (DGP) model for the Universe. We can convert the units of these sigma_v measurements to 270^{+40}_{-41} km/s and 320^{+41}_{-41} km/s respectively (assuming a LCDM universe), which are much lower than that expected based on recent low redshift (z<0.2) measurements of the peculiar velocity field (or ``bulk flows"), i.e., we would have predicted motions of ~ 600 km/s over our redshift range (0.16 < z <0.47) to be consistent with these local measurements. One possible explanation for such a large discrepancy is that our Galaxy is located in unusually over, or under, dense region of the Universe.

Our recent study of Galactic globular clusters using Ca and Stromgren uvby photometry has shown that many globular clusters have multiple red giant branch populations with distinct calcium abundances, in sharp contrast to the widely accepted idea of AGB pollution scenarios. This suggests that these globular clusters, like \omega Cen, are most likely the relics of more massive primeval dwarf galaxies that merged and disrupted to form the proto-Galaxy. In my talk, I will review current understanding of the multiple populations in globular clusters and will present some highlights of my survey.

The Lyman-alpha forest refers to numerous, narrow neutral hydrogen absorption lines blueward of the Lyman-alpha emission line ofhigh-redshift QSOs. The current paradigm of the Lyman-alpha forest favors that it arises from moderate amplitude density fluctuations in the warm (~10^4 K) photoionized, diffuse intergalactic medium(IGM) which traces the dark matter distribution in a simple manner. This interpretation has turned the Lyman-alpha forest into powerful cosmological probe at high redshifts, such as the matter power spectrum at smallest scales. They also provide a constraint onthe feedback between high-redshift galaxies and the IGM. At lower redshifts, the absorptions seen in low-redshift QSOs provide a clue on the missing baryon. In addition to this general discussion on the importance of the IGM, I will briefly discuss the current and upcoming instruments to study the IGM, such as COS on HST and the CODEX on the E-ELT.

One ingredient in an empirical birthrate estimate for pulsar binaries is the fraction of sky subtended by the pulsar beam: the pulsar beaming fraction. This fraction depends on both the pulsar’s beam geometry defined by the pulsar’s opening angle and the misalignment angle between its spin and magnetic axes. The current estimates for pulsar binary birthrates are based on an average value of beaming fractions for only two pulsars, i.e., PSRs B1913+16 and B1534+12. In this work, we revisit the observed pulsar binaries to examine the sensitivity of birthrate predictions to different assumptions regarding the pulsar beam geometry. The results show that, for those pulsars without any direct beam geometry constraints, the estimated beaming correction factor is likely to be smaller than six, a canonically adopted value when calculating birthrates of Galactic pulsar binaries. The median birthrate estimates for pulsar-white dwarf and pulsar-neutron star binaries in the Galactic disk, based on the best observational constraints, are 34 per Myr and 89 per Myr, respectively.

As the nearest rich and dynamically young galaxy cluster, Virgo is an ideal place to study great details of how galaxies interact with their surroundings. Using the data from our recent VLA HI imaging study (namely VIVA: VLA Imaging of Virgo galaxies in Atomic gas), I will present late type Virgo galaxies undergoing various environmental effects. I will discuss 1) which processes are dominantly affect galaxies in different density regions, 2) how far out the impact of the cluster reaches, and 3) how the environment may modify galaxies in morphology and color.

Shock waves in interstellar medium are collisionless and the shock transition is by the collective motion of underlying plasma (e.g., MHD turbulence). Two important consequences of collisionlesss shocks are 1) they do not partition energy equally among di?erent particle species, and 2) they accelerate cosmic rays. Balmer-dominated filaments, which represent fast non-radiative shocks into partially neutral medium, provide unique diagnostics for collisionless shocks. I'll review recent observations of Balmer-dominated filaments and their implication on the physics of collisionless shocks. In particular, I'll discuss how observations of Balmer-dominated filaments can constrain the cosmic ray acceleration process.

Plasma instabilities excited in collisionless shocks are responsible for particle acceleration. We have investigated the particle acceleration and shock structure associated with an unmagnetized relativistic electron-positron jet propagating into an unmagnetized electron-positron plasma. Cold jet electrons are thermalized and slowed while the ambient electrons are swept up to create a partially developed hydrodynamic-like shock structure. In the leading shock, electron density increases by a factor of about 3.5 in the simulation frame. Strong electromagnetic fields are generated in the trailing shock and provide an emission site. These magnetic fields contribute to the electrons transverse deflection behind the shock. We calculate the radiation from deflected electrons in the turbulent magnetic fields. The properties of this radiation may be important for understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets in general, and supernova remnants.

Nuclear rings are in most cases thought to be by-products of gas shock-focusing at Inner Lindblad Resonances (ILRs). AINUR (Atlas of Images of NUclear Rings) is an Atlas which includes images and metric measurements of all 113 known nuclear rings. This Atlas has been produced by checking and processing Hubble Space Telescope archive data from a complete sample of 488 galaxies. We made structure maps, Halpha and Paschen alpha continuum-subtracted images, and color-index maps in order to detect as many nuclear rings as possible. A few more nuclear rings have been added from a literature search. The 113 nuclear rings are found in 107 galaxies, six of which are elliptical galaxies, five are highly inclined disc galaxies, 17 are unbarred disc galaxies and 79 are barred disc galaxies. We find that dust nuclear rings are found in 6+-2% of elliptical galaxies and that star-forming nuclear rings occur in 19+-4% of the disc galaxies with types ranging from T=-3 to T=7. The peak of the star-forming nuclear ring distribution is found between Sab and Sb. The maximum possible radius for a nuclear ring in a barred galaxy is a quarter of the bar length. We find that the maximum possible relative size of a star-forming nuclear ring is inversely proportional to the non-axisymmetric torque parameter (``stronger bars host smaller rings'') and that the origin of nuclear rings, even the ones in non-barred hosts, is closely linked to the existence of dynamical resonances. We discuss implications for the lifetimes of nuclear rings and for the evolution of both the rings and their host galaxies.

To search for planets around intermediate-mass stars, evolved giant stars are the most suitable targets for Doppler spectroscopy-based planet searches because these stars have low surface activity and their spectra exhibit many sharp absorption lines. In recent years the number of planets found orbiting such evolved stars has dramatically increased and some properties of planetary systems have begun to emerge, although the number is still quite small compared with planets detected around solar-type dwarf stars. Now, we are carrying out a Korean-Japanese planet search program since 2005 and have just started a survey program of massive intermediate-mass giant stars in 2010. The aim of the programs is to show the statistical properties of planetary systems around intermediate-mass stars by precise radial velocity surveys of evolved GK-type giant stars together with collaborative surveys of the East-Asian Planet Search Network. In my talk, I introduce our planet searches and present current understandings of planets around evolved intermediate-mass stars.

Molecular outflows are believed to be an essential mechanism in the star formation process where they facilitate the collapse of a pre-stellar core into star by acting as a channel to remove an excess of angular momentum from the system. The outflows develop into massive extended structures hundreds of light years in length, and which evolve over timescales of tens of thousands of years. They may even be a source of turbulence in molecular clouds which helps regulate the star formation rate. We performed an investigation, via numerical simulations, of the properties of bipolar outflows and how they are effected by both the underlying jet beam and the surrounding ambient environment. Mass-velocity distributions were plotted in order to link the simulations to observations. Firstly we focused on simulating jets of various velocities and compositions, obtaining shallow mass-spectra (~1-2) which were independent of jet velocity, but found that steeper mass-spectra could be achieved through an atomic-jet/molecular-medium combination. Next we turned to the ambient environment and created realistic protostellar environments consisting of density gradients and density discontinuities. We found that a non-uniform medium lead to steeper mass-spectra, in line with those obtained from observations, and that the mass-spectrum of an outflow can vary substantially during its dynamical evolution.

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Studies of the highest redshift quasars probe the relation between the formation of the earliest supermassive black holes and galaxies. The quasar absorption lines trace the evolution of the intergalactic medium, and reveal when and how the reionization process happened, ending the cosmic dark ages. Detections of quasars at z>6 is challenging the standard picture of black hole growth in early Universe. They also show strong signs of on-going star-formation from their dust and gas emissions, suggesting the co-evolution of first generation black holes and galaxies. The absorption spectra of the highest-redshift quasars show strong evolution of Ly alpha optical depth, indicating that the neutral fraction of the intergalactic medium begins to increase rapidly, and suggests that we might be reaching the tail end of the reionization process.

Mass accretion onto compact objects like GBHS, NS and WD provides a platform to study the dynamics of material, structure and various physical processes. Here I show that the cross-correlation method is a potential tool to investigate and constrain the inner region of the accretion disk. The anti-correlated lags between two energy bands along with spectral studies can constrain the truncation accretion disk scenario in galactic black hole sources as well as in neutron star binary systems. We favour a geometry of accretion disk in which the soft photons are arriving from the Keprlerian disk and hard photons are originating from Compton cloud which is observed to be close to the central source. Such geometrical picture can consistently explain the lags, spectral changes along with rapid dynamical changes like QPOs. In case of Magnetic CV, anti-correlated lags can rigid the idea of blob accretion model which is often used to explain the excess soft X-ray spectral component in polars.

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Galaxy clusters are very important giant astrophysical laboratories in which one can study many interesting physical phenomena on giant scales. X-ray spectroscopy and analysis of the Sunyaev-Zeldovich effect play a crucial role to study interesting phenomena such as non-equilibrium ionization, non-thermal particle populations in galaxy clusters. The influence of high energy electron populations on measurements of metal abundances and on the He-like to H-like iron line ratio is considered. Measurements of the spectral slope of the Sunyaev-Zeldovich effect are proposed to obtain unbiased information about the specific properties of various electron distributions. It will be shown that the non-equilibrium ionization of iron can occur in galaxy clusters if the baryonic over-density is smaller than 11.0/tau, where tau<<1 is the ratio of the hydrodynamic structure age to the Hubble time.

예부터 우리 인간은 우주에 있어서 유일무이한 존재일까 하는 의문을 항상 갖고 있었다. 그 오랜 의문에 대한 대답이 前世紀가 끝날 무렵부터 서서히 밝혀지고 있다. 1995년, 스위스의 연구그룹이 페가사스座 51番星 주위를 돌고 있는 행성을 발견했다. 이 획기적인 발견에 의해 인간 이외의 지적 생명체의 존재를 찾는 여행의 一 幕이 열리게 되었다. 이러한 관측된 행성과 태양계의 행성과의 서로 다른 특징도 많이 볼 수 있다. 관측 기술의 진전에 따라 행성에 있어서 무엇이 보편적인 성질이고, 각각의 행성에 있어서 무엇이 특징인지 명확하게 되어가고 있는 것 같다. 그러나, 어떻게 행성이 형성되었는지의 이론적인 설명을 하지 않으면, 도대체 어떤 것에 의해 그 특징이 결정되었는지는 명확하게 할 수가 없다. 이론적인 행성형성의 설명이 이루어진다면, 형성된 행성표층의 환경까지도 推論 가능하게 된다. 推論된 행성의 표층환경에 대해, 생명에 대해 불가결한 아미노산이 형성 가능한가? 하는 생명의 기원에 관한 문제도 이론 가능하게 될 것이다. 이처럼 관측을 우선으로 한 행성형성의 이론적 짜임새를 만드는 것은 대단한 의미가 있다. 태양계 이외의 행성형성을 이론적인 검토를 하기 전에 자세한 관측이 가능한 태양계내의 행성형성과 원시지구 환경에 대해 조사, 연구하는 것은 대단히 중요하다고 생각된다. 본 강연은, 현재까지 얻어진 태양계형성에 관한 이론적 견해에 대해 소개하는 것을 목적으로 한다.

Massive stars and supernovae/GRBs are useful future tools for the probe of the early universe. As the formation of the first and second generations of stars is supposed to occur in metal-free/poor environements, the standard picture of massive stars, which is based on the sample in nearby galaxies including our own, may not be applicable. In this talk, I will address a few issues on the evolution of massive stars and their consequent explosions in the early universe. They include the effect of various physical processes (e.g. rotation, dark matter, pulsation) on the stellar evolution, the possibility of observing very energetic events like long gamma-ray bursts and some exotic types of supernovae at high redshift, and massive star populations in the early universe.

조선 후기에는 실학자를 중심으로 많은 서양의 학문을 받아들이는데 많은 노력을 기울였다. 그 중 역산 관련 전문 서적들 뿐만 아니라 천문도를 비롯한 다양한 천문기기들도 도입하여 사용하였다. 천문기기 중에서 역산과 관련하여 중요하게 사용되었던 것이 간평의다. 본 발표에서는 서양의 영향에 의해서 제작된 간평의의 역사와 구조 특징에 대하여 알아보기로 한다. 이것은 특정한 지방의 위도에 따라 일출 시각, 일몰 시각, 낮과 밤의 길이 등을 간단히 계산하고 쉽게 사용할 수 있다. 조선시대 정교하게 만든 간평의의 모습은 간단한 구조를 가졌지만 그 작도 방법은 쉽지 않다. 이러한 간평의를 정교하게 작도한 것으로 미루어 보아 당시 조선시대의 서양 천문학 지식의 이해 정도가 높았음을 알 수 있다. 이미 당시에 서양의 투영법이나 태양 운행과 관련한 작도를 능숙하게 할 수 있을 정도로 서양 천문학에 대한 이해가 높았다. 이러한 간평의의 제작은 당시 시헌력을 사용하면서 정기법을 이용한 태양의 일출 및 일입 시각을 절기와 관측 지방에 따라 정확하게 계산하는데 기본적 자료를 사용했다. 당시의 책력에 들어갈 가장 중요한 요소는 일출과 일몰 시각을 비롯하여 낮의 길이 변화에 대한 것이다. 이러한 간단한 기기를 이용하여 절기에 따른 각 지방의 일출과 일몰 시각 결정과 밤과 낮의 길이 결정을 손쉽게 할 수 있는 방법을 체득하고 있었다. 또한 이를 이용하여 역산의 편리성을 도모하였다.

우리민족은 옛 부터 하늘을 관찰하는 천문대를 축조하고 하늘의 천변현상을 관측하여 왕조들의 역사서 속에 기록하였을 뿐만 아니라, 많은 천문관련 사료와 유물을 자랑하는 하늘의 과학문화를 일궈 낸 자랑스러운 전통을 이어온 민족이다. 실제로 우리나라의 천문관측에 사용한 천문의기(天文儀器)에 관한 기록은 조선 초기 부터 구체적으로 기술하고 있다. 세종시대는 세계 과학기술사를 빛낸 세계 최대 규모의 천문시설과 천문의기를 제작한 많은 창제물들의 기록이 남아 있지만 모두 사라져 당시의 유물을 볼 수 없어 아쉬움을 금할 길이 없다. 필자는 지금까지 사라져 버린 고천문의기와 현존하는 유물일지라도 훼손되어 원형과 작동상태를 볼수 없는 천문의기들을 문헌을 통하여 천문의기들의 작동모델을 설계하고 복원하는 과정과 복원결과를 제시하고자 한다. 복원과정 에서 천문의기(天文儀器)에 관한 고 문서 기록은 그림이나 설계도로 표현된 것은 거의 찾아볼 수는 없지만 일부 의기는 제작에 관해서 규격과 용도와 기능을 알 수 있도록 제작 명이 기술되어 있다. 왕조사나 『제가역상집(諸家曆象集)』같은 고문서 기록을 살펴보았고, 현존하는 유물의 부품이나 또는 중국의 유물들을 학술 조사하여, 그 구조와 기능을 분석해 복원힌다. 복원과정을 살펴보면 천문의기 복원(復元)은 모형(模型)을 만드는 것이 아니며 때문에 기초설계 과정에서 부터 외형적 형태와 구조 등을 학계고증 과정 등을 거쳐, 가급적 자재와 공법들은 전통적인 방식으로 제작하고 있다. 각종 부속부품이나 장식문양 등 제작과정의 고증이 필요하고 또 각 부품들이 작동할 수 있도록 작동모델을 복원하여야 하는데, 실제 정교하게 가공하지 않으면 작동이 불가능하다. 천문의기는 대체로 정교한 계측기 종류기 때문에 정밀하게 측정하는 눈금이 새겨지도록 청동으로 부어 만들 때는 시행차고 많이 있었다. 뿐만 아니라 천문의기들은 대체로 왕궁에서 사용함으로 그 외형적 구조와 모양이나 문양도 당시 왕권을 상징하고 있고, 용(龍)의 형상과 문양들은 예술적인 손길이 많이 필요로 한다. 설치과정에서는 정확한 극축의 방위와 설치장소의 위도에 맞도록 정밀하게 조정되어 설치해야만 한다. 복원한 천문유물들은 새로이 재 창재를 이룬 것이라고 볼수 있다. 지금까지 복원하여 설치한 천문의기는 간의(簡儀)와 소간의, 혼천의가, 혼상(渾象), 일성정시의(日星定時儀) 등이 있고, 각종 해시계 거운데 앙부일귀와 정남일귀 현주일귀 지평일귀가 있다. 길이 25m 규(圭)에 눈금을 새겨 간의대 서쪽에 나란히 설치하고 8m 높이의 규표(圭表, 銅表)는 설계를 완성하였다. 이와 같은 각종 천문기기들과 시계들은 매우 정교하게 제작하여 정밀하게 측정할 수 있는 계측기로서 당대 최첨단 과학기기들이다. 아울러 세종시대의 혼천의와 자격루 등의 전통을 이어온 천문기기로 세계 유일하게 현존하는 송이영의 혼천시계(국보 제230호, 만 원권 지폐의 혼천의 부분의 그림)의 작동 모델을 완성하였다. 이 혼천시계는 우리나라의 전통적인 시계기술의 축척과 천문학적 원리를 바탕으로 당시 서양의 기계시계 기술을 집약하여 이룩한 천문시계이다. 훼손된 유물을 살펴 작동 모델을 복원함으로서 혼천의의 설치한 태양과 달의 천상운행의 모습을 실시간으로 지켜볼 수있게 되었다.

It is a fascinating fact that a solitary star like the Sun emits intense X-rays from its outer atmosphere. Observations with the Japan- US Yohkoh satellite showed that all the sporadic heating from X-class flares to ubiquitous tiny bursts in the solar corona is due to magnetic reconnection; a process to efficiently annihilate magnetic fields with opposite direction and generating jets, heats and non- thermal particles. These activities on the surface of the star are driven by magnetic fields created by the interaction of flow and seed magnetic fields inside the Sun (dynamo mechanism). The magnetic field strength on the surface of the Sun exceeds 1kG, while that at the bottom of the convection zone may exceed 100kG. They are too strong, far stronger than the equi-partition magnetic field strength, the energy of which is the same as that of the local convection motion. Though a dynamo mechanism can amplify field strength upto the equi-partition field strength, it is perceived possible to have field strength beyond that threshold. Such too-strong magnetic fields can be found elsewhere in the universe, namely pulsers (1012G), magneters (1015G), galaxies and clusters of galaxies (a few micro G), which is again too strong in terms of that in early universe (<10-15G). The dynamo mechanism for the sun and these objects is poorly understood. The Hinode spacecraft was successfully launched in September 2006 using a JAXA’s M-V launch vehicle. It comprises an observatory style set of instruments that function together to answer the fundamental questions of how magnetic fields are formed and how they dissipate to create the solar corona. This subsequently addresses all the phenomena that have an impact on the Sun-Earth system, such as the formation of the solar winds, triggering of flares with intense non- thermal acceleration and coronal mass ejections, and formation and maintenance of filaments and prominences. The concept of Hinode is that two X-ray and EUV telescopes observe the dissipation part of the magnetic life-cycle, while the visible light telescope simultaneously observes the generation and transport of magnetic field. Hinode is the Japan’s third solar mission with participation of NASA and UK STFC (then PPARC) and subsequently ESA. Hinode has higher temporal, spatial and velocity resolution than any satellite previously and is probing wavelength regimes that have never had such continuous time coverage available. This has allowed us to discover waves in spicules, prominences and on the photosphere, ubiquitous jets in chromospheres, ubiquitous transient horizontal magnetic fields on the photosphere suggesting turbulent dynamo process, supersonic down-flow and convective collapse resulting in super equi-partition magnetic field strength, emergence of large- scale flux rope from below the photosphere, kG-magnetic patches in the polar regions, identification of the origin of slow solar wind, and enigmatic fine-scale flows in the prominence. This talk summarizes how these new results from Hinode are addressing these critical questions as well as probing fundamental physical processes that will have applications in many other scenarios across the universe.

본 연구는 수천 개의 은하를 포함하고 있는 처녀자리 은하단에서, 은하와 은하 사이를 방랑하는 구상성단으로 이루어진 거대구조를 발견한 내용을 소개한다. 처녀자리 은하단 에서 은하간 구상성단은 어떤 분포를 보이는 지를 보여주며, 이러한 발견이 갖는 의의와 함축하는 내용을 언급한다. Globular clusters are found usually in galaxies and they are an excellent tracer of dark matter. Long ago it was suggested that there may exist intracluster globular clusters (IGCs) bound to a galaxy cluster rather than to any single galaxy. Here we present a map showing the large scale distribution of globular clusters over the entire Virgo cluster. It shows that IGCs are found out to 1.5 Mpc from the Virgo center, and that they are concentrated in several substructures much larger than galaxies. These objects might have been mostly stripped off from low-mass dwarf galaxies.

Among the most fundamental questions in astronomy are those concerning the formation of stars and planets from interstellar material and the feedback mechanism from stars on the dynamics and chemical evolution of ISM itself. Recently, observations at radio, millimeter and sub-mm molecular-line wavelengths provide crucial insights into almost all phases of the ISM, from overall galactic evolution to the composition of planetary atmospheres and hence the possible development of life forms on Earth-like planets. Molecules are present in all these environments, proving extremely useful tracers of the structures of circumstellar shell, planetary nebulae, dense and diffuse clouds, cloud cores, and protostellar disks. Because of their unique connection to this wide range of astrochemical objects, obtaining a clear understanding of the chemistry of interstellar molecules is essential to evaluating the life cycles of the ISM and its relationship to planet solar system formation. Although astrochemical observations continue to lead to detection of unexpected molecules, however, they are relatively decoupled from laboratory spectroscopic and chemical dynamic studies which enable formulation of realistic predictive models of the evaluation of interstellar chemistry in astrochemical relevant objects. We here present new results for some astrochemically relevant reaction processes obtained using reflectron velocity map ion imaging and Megapixel ion imaging techniques developed in laboratory recently. Using reflectron multimass velocity map ion imaging, we studied the vibrationally mediated photodissociation dynamics in the ethylene cation, and the conformer selective photoionization and photodissociation dynamics in propanal cation from the well defined quantum states. The experimental results show strongly coupled angular and translational energy distributions revealing features of the reaction not seen in previous studies. These observations provide new fundamental insights into the dynamics of the astrochemical reactions.

Recent discovery of high redshift Gamma-ray Bursts (GRBs) including GRB090423 at z=8.2, the most distant object known so far, provides an interesting new possibility to explore the early Universe in the Epoch of Reionization (EOR). A next generation multi-wavelength observatory, the Energy X-ray Imaging Survey Telescope (EXIST) is proposed to probe the early Universe with high redshift GRBs, to survey black holes on all scales, and to monitor the transient X-ray Universe. To accomplish this, EXIST consists of three complementary telescopes; a High Energy Telescope (HET), a Soft X-ray Imager (SXI), and an Optical/Infrared Telescope (IRT). Here I will review the EXIST mission concept and the primary sciences. We have been advancing the detector technology required for the HET through a series of on-going balloon-borne experiments called ProtoEXIST. I will show the result of the first balloon flight ProtoEXIST1 from Ft. Sumner, New Mexico on 2010 Oct 9.

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Whether supernovae (SNe) are a significant source of dust has been a long-standing debate. Abundant dust observed in high-redshift galaxies raises the fundamental astrophysical question of the origin of dust in Universe. AGB stars are too old to have evolved in early Universe. In contrast, SNe can occur within millions of years of the first generation of stars. I present dust formation observed in young supernova remnants (YSNRs) with Spitzer. Cas A and G54.1+0.3 YSNRs show unique dust features peaking at 21-micron, and E0102 and N132D show 18-micron dust features. In Cas A, we identify three distinct ejecta dust populations based on their continuum shapes including line-free map of 21 micron-peak dust closely resembles the Ar, O and Ne ejecta-line maps implying that dust is freshly formed in the ejecta. Spectral fitting of dust continuum shows amorphous dust and unique SN-produced dust compositions. We report detection of CO first overtone and fundamental bands from Cas A, indicating continuation of astrochmical processes since the explosion. I discuss compositions and masses of dust and association with ejecta and finally, dust contribution from SNe to early Universe.

I will present results of a program to map the distribution of molecular gas toward several well-known regions of massive star formation, and also selected nearby Bok Globules which are forming solar-mass stars. The maps show clear evidence of energy injection processes from stellar radiation, winds, and H II region expansion, in shaping and controlling the star formation process. Connections with infrared observations from the Spitzer Infrared Space Telescope will be emphasized. The observations were made with the Steward Observatory Heinrich Hertz Submillimeter Telescope. I will give a brief technical summary of the telescope and instrumentation used in our study.

The Sun is the most energetic natural particle accelerator in the solar system, producing ions up to many GeV energies and electrons up to ~100s of MeV in both large solar flares and fast coronal mass ejections (CMEs). Large solar flares are the most powerful explosions in the solar system, releasing up to ~1032-33 ergs in 100-1000 s, with >~10-50% of this energy going to accelerating electrons to >~20 keV and a comparable amount to accelerating ions above several MeV energy. Imaging of the hard X-ray (HXR)/gamma-ray continuum and gamma-ray line emission produced by the accelerated electrons and ions, respectively, by the RHESSI (Ramaty High Resolution Solar Spectroscopic Imager) spacecraft, shows that the process of magnetic reconnection underlies both the flare energy release and the acceleration of electrons and ions. Fast (>~103 km/s) CMEs drive shock waves that appear to accelerate the Solar Energetic Particles (SEPs) at altitudes of ~2-40 Rsun, with up to ~10% of the total CME kinetic energy going to the accelerated ions. Observations from RHESSI confirm that the flares associated with SEP events all have hard X-ray bursts with a unique soft-hard-harder spectral evolution with time. The relationship between the CME and these flare hard X-ray sources in the chromosphere is presently not understood.