Subaru Seminars

The Cherenkov Telescope Array (CTA) will be the next generation ground-based gamma-ray observatory for Very High Energy Astrophysics (VHE), designed to improve the sensitivity by an order of magnitude compared to current instruments. Built by a worldwide consortium of 29 countries, CTA will consist of two arrays, in La Palma (Spain) and Paranal (Chile), for a full sky coverage. Both arrays will be made of tens of Cherenkov telescopes of three different apertures to cover the energy range between 20 GeV and 300 TeV. The Schwarzschild-Couder telescope (SCT) is an innovative candidate for the CTA medium size telescopes (9.6 m aperture), featuring a two-mirror aplanatic optical system with a larger field of view (8 deg) and reduced plate-scale compared to traditional Davis-Cotton or parabolic designs. These improvements require a large (5 m) aspheric and highly curved secondary mirror as well as a sophisticated alignment system based on several hundred actuators and edge sensors. In this talk I will present the work done at UCLA to design and build the optical and alignment systems for SCT and some of the main technical challenges that have been overcome. I will also give a status update on the first full-size SCT prototype currently under construction at the Fred Lawrence Whipple Observatory in Arizona.

Quasars at high redshift are an important and unique probe of the distant Universe, for understanding the origin and progress of cosmic reionization, the early growth of supermassive black holes, and the evolution of quasar host galaxies and their dark matter halos, among other topics. We will present the latest results from our SHELLQs (Subaru High-z Exploration of Low-Luminosity Quasars; arXiv:1603.02281) project, a new spectroscopic survey for low-luminosity quasars at z > 6. By exploiting the exquisite imaging data produced by the Subaru Hyper Suprime-Cam survey, we aim to probe quasar luminosities down to M1450 ~ -22 mag, i.e., below the classical threshold between quasars and Seyfert galaxies. Candidate selection is performed by combining several photometric approaches including a Bayesian probabilistic algorithm. A large spectroscopic observing program is underway, using Subaru and other 8-10m telescopes; in particular, SHELLQs has been approved as a Subaru intensive program to use 20 nights in the coming four semesters. As of August 2016, we have discovered 31 quasars and 8 bright galaxies at z ~ 6 and beyond. This result indicates that we are starting to see the steep rise of the luminosity function of high-z galaxies, compared with that of quasars, at magnitudes fainter than M1450 ~ -22 mag or z(AB) ~ 24 mag. Multi-wavelength follow-up studies of the discovered objects as well as further survey observations are ongoing.

From astrometric and spectroscopic observations in the galactic center, we can see stars, which are called the S stars, moving around Sgr A*. The motion of the S stars tell us the mass of Sgr A* and it is about 4 million times masses of the sun. While we know the mass of the SgrA*, we do not know well about its spin. In this talk, we assume that the metric around the Sgr A* is the Kerr metric and constrain the spin parameter including the over-spinning region by the motion of the S stars.

The Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) is an integral field spectrograph (IFS) that has been built for the Subaru telescope. CHARIS has two imaging modes; the 'high-resolution' mode is R82, R69, and R82 in J, H, and K bands respectively while the 'low-resolution' discovery mode uses a second 'low-resolution' prism with R19 spanning 1.15-2.37 microns (J+H+K bands). The discovery mode is meant to augment the low inner working angle of the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) adaptive optics system, which feeds CHARIS a coronagraphic image. CHARIS constrains spectral crosstalk through several key aspects of the optical design. We report on the measured repeatability and stability of these mechanisms, measurements of spectral crosstalk in the instrument, and the propagation of these errors through the data pipeline. Another key design feature of CHARIS is the prism, which pairs Barium Fluoride with Ohara L-BBH2 high index glass. The dispersion of the prism is significantly more uniform than other glass choices, and the CHARIS prisms represent the first NIR astronomical instrument that uses L-BBH2 as the high index material. We will also discuss the lessons learned during the testing process and their impact on future high-contrast imaging spectrographs for wavefront control.

Solaris is a Polish scientific undertaking aimed at the detection and characterization of circumbinary exoplanets. To accomplish this task, a network of four fully autonomous observatories has beed deployed in the Southern Hemisphere: Solaris-1 and Solaris-2 in the South African Astronomical Observatory in South Africa, Solaris-3 in Siding Spring Observatory in Australia and Solaris-4 in Complejo Astronomico El Leoncito in Argentina. The four stations are nearly identical and are equipped with 0.5-m Ritchey-Cretien (f/15) or Cassegrain (f/10, Solaris-3) optics and high-grade 2K x 2K CCD cameras with Johnson and Sloan filter sets. The design and implementation of low-level security, data logging and notification systems, weather monitoring components, all-sky vision system, surveillance system and distributed temperature and humidity sensors will be presented. The Solaris-1 telescope is additionally fitted with a medium resolution low cost wine-bottle-size Echelle spectrograph that is operated semi-automatically. Custom hardware components have been designed to allow both spectroscopic and photometric observations. The setup is controlled via dedicated software. Apart from the hardware description, first photometric and spectroscopic results will be presented.

I will talk about my study for surveying over-density regions through damped Ly-alpha absorption (DLA) systems. The over-density region is a key component to understanding the structure formation in the Universe. It should be noted that previous surveys for high-z over-density regions need emission from galaxies. However, in the high-z Universe, large fraction of baryons in galaxies could be in the gas phase and thus could be missed. We are focusing on the DLA which is a class of quasar absorption-line systems to study about gases at high-z. Since DLA can be recognized as by their H I column densities regardless of their luminosities, we can effectively investigate the nature of gases in the high-z Universe through the DLAs. We are now working to examine the nature of the DLAs and their environments. Based on the BOSS DLA catalog, we investigated the spatial and redshift distribution of DLAs and found some possible ``DLA clusters'' where there are some DLAs in very narrow regions. To examine whether or not those possible DLA clusters corresponds to over-density regions, narrow-band imaging observations are useful. In this talk, we report the results of our Subaru/Suprime-Cam narrow-band observation for line-emitting galaxies around some possible DLA clusters.

One of the goals of the HSC survey is to search for high redshift QSOs. By combining near-infrared (NIR) and mid-infrared surveys with the HSC survey, we aim to search for z>6.7 QSOs. Because the HSC survey at Y is usually much deeper than other wide-area NIR surveys. Taking advantage of this, we tried the followings: We first utilized the deep NIR survey, UKIDSS-UDS (JAB=24.9; 5-sigma) to search for z-dropout sources (detected in HSC-Y in wide layer and longer UKIDSS bands, and not detected in all shorter HSC bands). We then utilized wide-field VIKING survey to search for Y-dropout sources (detected in VIKING-J, H, and K bands, and not detected in HSC-Y in wide layer). In this talk, I will present my results, and compare my result with the bayesian probability used by HSC high-z quasar search team.

We compare the isophote shape parameter a4 of early-type galaxies (ETGs) between z~1 and 0 as a proxy for dynamics to investigate when the dynamical properties of ETGs are characterized. We create cluster ETG samples with spectroscopic redshifts from the Hubble Space Telescope Cluster Supernova Survey for z~1 and the Sloan Digital Sky Survey for z~0. We have developed an isophote shape analysis method which can be used for high-redshift galaxies and applied the same method for both the z~1 and 0 samples. We find similar dependence of the a4 parameter on the mass and size at z~1 and 0; the main population of ETGs changes from disky to boxy at a critical stellar mass of log(M*/M_sun)~11.5 with the massive end dominated by boxy. The similar critical mass between these redshifts is consistent with a scenario that the mass quenching is the origin of massive boxy ETGs. The disky ETG fraction decreases with increasing stellar mass both at z~1 and 0, and we do not find significant difference in the fraction between these redshifts in all stellar mass bins. Although uncertainties are large, the results suggest that the isophote shapes and probably dynamical properties of ETGs in massive clusters are characterized at z>1. The constant disky fraction between z~1 and 0 implies that the intermediate mass ETGs in clusters should keep their dynamical properties during the size and morphological evolution in z<1.

I will review and revisit the basic premise that H2 gas in galaxies is always heated by the FUV component of starlight via the photolectric effect on dust grains. Other H2 gas heating mechanisms will be presented, and their effects on the H2 thermal state will be discussed. Their impact on the initial conditions of star formation across the Universe is expected to be profound, and it can no longer hide behind large columns of gas and dust, no matter if it is in the Milky Way or in other galaxies I will end by outlining ways to lift the veil and and we may expect.

Images of dust continuum and CO line emission are powerful tools for deducing structural characteristics of galaxies such as disk sizes, H2 gas velocity fields, and enclosed H2 and dynamical masses. We report on a fundamental constraint set by the Cosmic Microwave Background (CMB) on the observed structural and dynamical characteristics of galaxies as deduced from dust continuum and CO line imaging at high redshifts. As the CMB temperature rises in the distant Universe, the ensuing thermal equilibrium between the CMB and the cold dust and H2 gas progressively erases all spatial and spectral contrasts between their brightness distributions and the CMB. This strongly biases the recoverable H2 gas and dust mass distributions, scale lengths, gas velocity fields, and the dynamical mass estimates, for high redshift galaxies. This limitation is unique to mm/submm wavelengths, and unlike its known effect on the global dust continuum and molecular line emission of galaxies, it cannot be simply addressed. We nevertheless identify a unique signature of CMB affected continuum and line brightness distributions, namely a rising rather than diminishing contrast between such brightness distributions and the CMB once frequencies beyond the Raleigh-Jeans limit are used for imaging the cold molecular gas and dust in distant galaxies. Such effects progressively change the apparent gas and dust distribution and velocity field, leading to biased size and mass estimates of high-redshift galaxies, which will be obtained with ALMA, JVLA, and SKA.

As datasets grow larger and more complex visualization will play an increasingly important in data exploration and discovery. This talk will give an overview of some of the critical software and hardware issues that need to be tackled in the big data era. I will discuss the state of the Worldwide Telescope which has recently been adopted by the American Astronomical Society. Finally I will describe the opportunity to transform the modern digital planetarium into a big data visualization facility, of use to researchers across disciplines.

In the local universe, the tight correlation between galaxy spheroidal stellar mass (Msph) and their central SMBH mass (MBH) was found by previous studies (MBH/Msph ~ 0.0015), suggesting co-evolution between galaxies and SMBHs. To reveal galaxy and SMBH formation mechanisms, one of the keys is exploring the redshift evolution of MBH/Msph ratio, and we have been carried out near-IR observations of z ~ 3 QSOs. MBH was derived by the most reliable Hβ method which uses Hβ (4861A) emission line width and AGN continuum luminosity at 5100A. For Msph, multi-band (J (1.2μm), K'-band (2.2μm)) near-IR imaging method is adopted to obtain accurate Msph. To subtract bright AGN glare accurately for obtaining host galaxy light, we established our original analysis method. We derived MBH for 28 z ~ 3 QSOs, and also derived Msph for 9 out of 28 QSOs, and we found that MBH/Msph at z ~ 3 is larger (MBH/Msph(median)~0.046) than the local relation (MBH/Msph ~ 0.0015).

We have recently suggested that a giant planet well beyond Neptune is required to explain unexpected clustering in the orbits of very distant and eccentric Kuiper belt objects. I will present the evidence for this clustering as well as the dynamical evidence that a giant planet is responsible. Finally, I will discuss prospects for directly detecting this planet in the near future and what it might tell us about the formation of the solar system.

Using ground- and space-based spectroscopy, we present the rest-frame optical spectral properties of 181 distant and luminous quasars to understand the growth of the most massive black holes. Including the latest Akari space observations of H-alpha emission at 3<z<6, we extend scaling relations between rest-frame optical continuum and line luminosities and find that a single log-linear relation holds over 42<log L(5100, ergs/s)<47 and 0<z<6. Similar scaling relations are found between the optical and the UV for continuum luminosities and line widths. Applying these scaling relations to the locally derived H-beta black hole mass (M(BH)) estimator, we derive M(BH) estimators based on H-alpha, MgII, and CIV lines. We find that masses based on UV lines are consistent with those based on Balmer lines, but with a large intrinsic scatter of 0.40 dex for the CIV estimates. Our Akari H-alpha spectra confirm the existence of black holes as massive as ~10 billion solar masses out to z~5, confirming with a more secure footing previous MgII studies that showed rapid black hole growth in the early universe. With the IRTF spectra of extremely massive quasars at 1<z<2 we investigate possible systematics that could bias the black hole mass measurements, and discuss implications for the coevolution of the most massive black hole-galaxy systems.

The study of protoplanetary disks was for a long time based on indirect measurements of gas and dust, limiting our understanding of planet formation. The arrival of ALMA has revolutionized our view of the structure of these disks. The Early Science ALMA observations in the last few years have revealed rings, asymmetries, dust/gas segregation, gas dynamics, evidence for dust trapping and vortices, and many more exciting phenomena that have been predicted for decades in physical models of disks. The structures provide evidence for the presence of embedded planets, which can be confirmed by direct imaging such as done with Subaru. In this talk I will discuss the findings of ALMA observations and their implications for finding the embedded planets.

Direct detection of the infrared radiation from exoplanets and their environment falls in an angular resolution niche: the scale of our solar system in the nearest star forming regions falls right at the diffraction-limit of the world's largest telescopes. I will show some highlights from the techniques of kernel-phase and aperture-mask interferometry that are currently the world-leaders in infrared imaging at the diffraction-limit for typical adaptive optics Strehl ratios. At the youngest ages, I will show how radiation from planetary systems in the process of formation can be directly imaged, focusing on multi-epoch monitoring of the resolved emission seen within the disk gap of LkCa 15, interpreted as a planet - LkCa15b. Recent results from the Magellan AO team have discovered H-alpha from an accretion shock on LkCa15b, and I will describe how a new module on Subaru's SCExAO, RHEA, could soon provide a similar capability here. RHEA will also be able to significantly extend the reach of 8m class telescopes in watching the final stages of evolution of giant stars, by combining very high (8 milli-arcsec) spatial resolution and spectral resolution (R~60,000). Finally, I will briefly mention the internationally collaborative Planet Formation Imager project as a long-term vision for imaging exoplanet birth.

The evolution with cosmic time of the star formation rate density (the Lilly-Madau plot) and of the "Main Sequence" star formation rate--stellar mass relation are two well established observational facts. In this seminar the implications of these two relations combined are analytically explored, showing that quenching of star formation must start already at very early cosmic times and the quenched fraction then dominates ever since over the star forming one. Thus, a simple picture of the cosmic evolution of the global star formation rate density is derived, in terms of the interplay between star formation and its quenching.

The AGN outflow is one of the most important key ingredients for the evolution of quasars as well as for the galaxy formation/evolution. A fraction of absorption lines in quasar spectra are believed to arise via the outflow rather than intervening objects like foreground galaxies and the IGM. Thus, absorption lines are powerful and unique tool to probe the outflows in quasars, which are difficult to be directly observed. However, the weakness of the past studies is that we can trace the outflow through only single sight-line toward the nucleus for each quasar. Using Subaru/HDS and VLT/UVES, we performed high-resolution (R~33,000) spectroscopic observations of images A and B of a gravitationally lensed quasar SDSS J1029+2623 at z~2.197 whose image separation angle (~22.5 arcsec) is the largest among those discovered so far. We discovered that each image has different intrinsic levels of absorptions on the blue side of broad emission lines, and then confirmed that the difference is not due to time variability of the absorption profiles over the time delay between the images (~744 days) but rather due to differences along the sightlines. We discuss a possible geometry and internal structure of the outflowing wind based on these results.

The Canadian Astronomy Data Centre (CADC) has a 30 year history of data management supporting the science of astronomy. The CADC was born along with the Hubble Space Telescope (HST) and has contributed strongly to the pioneering efforts that have led to the demonstration that more science comes from "archival" data than comes from the initial research of HST Principal Investigators.

The CADC became a multi-observatory data centres over 20 years ago and handles data from several major facilities and numerous projects. We have been world leaders in integration of all of our data collections into a single homogeneous data system and we are leaders in the International Virtual Observatory Alliance movement.

For the past five years the CADC has collaborated with the university-led Canadian Advanced Network for Astronomical Research in creating and operating a cloud- based distributed storage and processing system to support astronomy research. The CANFAR platform aims to deliver a national computing infrastructure for data- intensive science that satisfies the needs for scalability and flexibility that the era of Big Data demands. CANFAR and CADC are being extended to the international community in collaboration with the European Grid Infrastructure project and we plan to operate and integrated system of CANFAR nodes in Italy, France, Hawaii, and elsewhere.

The primary scientific output from an astronomical telescope is the collection of papers published in refereed journals. A telescope's productivity is measured by the number of papers published which are based upon data taken with the telescope. The scientific impact of a paper can be measured quantitatively by the number of citations that the paper receives. In this paper I will examine the productivity and impact of over 25 telescopes, mainly optical/IR, with apertures larger than 3.5-m for the years between 2009 and 2013. I will also examine how the telescopes are connected via their publications as well as the productivity and impact of individual instruments for several telescopes.

In this talk I will focus on two projects: (1) super star cluster feedback in 30 Doradus, and (2) super star cluster formation near galactic nuclei. I will present the first fully calibrated NEWFIRM H2 1-0 S(1) image of the entire 30 Doradus nebula. Together with a NEWFIRM Brγ image of 30 Doradus, our data reveal the morphologies of the warm molecular gas and ionized gas in 30 Doradus. Based on the morphologies of H2, Brγ, CO, and 8 μm emission, the H2 to Brγ line ratio, and Cloudy models, we find that the H2 emission is formed inside the photodissociated regions of 30 Doradus, 2-3 pc to the ionization front of the H II region, in a relatively low-density environment. Comparisons with Brγ, 8 μm, and CO emission indicate that H2 emission is due to fluorescence, and provide no evidence for shock excited emission of this line. I will also present a straightforward approach to study young and highly obscured super star clusters using ground-based MIR observations, to explore the universality of cluster formation efficiency and cluster mass function near galactic nuclei of face-on spiral galaxies. We mapped the nuclei of NGC 6946, IC 342, Maffei 2, and NGC 7714 in [NeII] using COMICS on Subaru Telescope. We identified 32 super star cluster candidates in [NeII] , as well as very extended emission which is presumably associated with non-compact, field star formation. The cluster formation efficiencies are estimated to be < 20%, while the cluster mass function shows a power-law index of -1.7. The results of cluster formation efficiency and mass function are consistent with that found in other galactic environments, suggesting universal, environment-independent formation processes of super star clusters. I will then end the talk with a brief introduction of the queue-mode operation at Subaru Telescope.

I present our work on applying the Deep Neural Network (DNN) to an astronomy research project. DNN is the hottest topic in machine learning researches, due to its record-breaking performance in several machine learning problems. After introducing DNN briefly, we present our application of DNN to help astronomy researchers to identify "supernova" and "bogus (non-star)" image patches taken by the SUBARU telescope. Our DNN model is trained to classify an image patch into a supernova class or a bogus class, observing a collection of measurements extracted from image patches shot by the SUBARU HSC. The classification performance of DNN is superior to existing machine learning techniques, even if the number of observation is not so much large. An automatic filtering of image by machine learning techniques will reduce efforts of astronomy researchers very much in choosing supernova candidates to be tested with spectrum analyzers.

Since 2014, a large survey project using Subaru/HSC(300 nights for 5 years) has started to study the cosmology and to search for optical transients. The problem in this survey is to find real transients from candidates including a large amount of bogus objects in difference images. We present the process of selection of supernovae using machine learning techniques. I present the boosting method, and Ishiguro-san shows the Deep Neural Network.

The global star formation (SF) laws - the relations between star-forming gas and SF rate (SFR) - are reexamined in a large sample of 181 local star-forming galaxies with infrared luminosities (SFR) spanning almost five orders of magnitude. The surface density of dense molecular gas (as traced by HCN) has the tightest and linear correlation with that of SFR (ΣSFR). The ΣSFR is a steeper function of the total (H2+HI) Σgas than that of molecular gas ΣH2. We further show that the SFR and a variety of dense gas tracers (e.g., HCN, CS, their high-J and high-J CO) are all linearly correlated for both the Galactic dense cores and star-forming galaxies near and far. This has immediate implications on the modes of SF in galaxies because the dense cores are the sites of active SF, and thus the basic units in contributing to SF. The SFR should depend linearly upon the mass of dense molecular gas (the SF law!). These ground-based observations of last decade and recent Herschel results highlight what the ALMA is delivering on the studies of "SF laws" across large redshift ranges over wide SF scales.

Mauna Kea is one of the premier sites in terms of atmospheric turbulence induced image quality for astronomical observation. As such it has been the site of many adaptive optics (AO) developments, starting in the early 90's. I first came to Mauna Kea in 1994 and have worked on Mauna Kea adaptive optics projects for 20 years, at Keck, CFHT and since 2013, I have been a jointly appointed adaptive optics scientist between Gemini Observatory and Subaru Telescope. In this talk, I will review the developments of adaptive optics on Mauna Kea, and my personal experiences of this history. Astronomical observatories, and astrophysics itself, have undergone a profound transformation in the last twenty years towards "Big Science", something I witnessed in adaptive optics. Instruments have become more expensive and productivity metrics have also transformed our approach to risk-taking and uncertainty, with consequences of the application to the scientific method. In fact, most instruments are now too large to be built by observatories themselves: they are the result of multi-institute collaborations and in fact some large research institutes, such as AAO or NRC-HIA, have become almost dedicated instrumentation centers. Furthermore, observatories are developing telescope time exchange programs to try to reduce duplication of effort. This shift from competition to collaboration led to my joint appointment between Gemini Observatory and Subaru Telescope and I will discuss some of the ideas and difficulties that the last three years generated.

We performed a comprehensive analysis of the Herschel spectra of BHR71, an embedded Class 0 protostar. We recover 66 lines in the central spaxel, and more than 700 lines are detected in all spaxels in PACS, and SPIRE. This line fitting result is part of our CDF (COPS-DIGIT-FOOSH) Archive, which is publicly available in Herschel Science Archive. The CO rotational diagram analysis shows four excitation temperature components, 51 K, 153 K, 408 K, and 1053 K. Low-J CO lines trace the outflow while the high-J CO lines are centered on the infrared source. The low-excitation emission lines of water trace the large-scale outflow, while the high-excitation emission lines trace small scale distribution around the equatorial plane. We model the structure of the envelope using dust radiative transfer by Hyperion to fit the spectral energy distribution (SED) observed by Spitzer and Herschel. The model incorporates rotational collapse and an outer static envelope as well as outflow cavity and disk. Our exploration of parameter space shows that the evolution of a collapsing envelope can be constrained by the Herschel SED and that the structure of outflow cavity plays a critical role in the shorter wavelength. We found the density profile of a cavity with a power law with a constant-density inner region can reproduce the observations. The high central luminosity in the best-fit model shows a hint of a higher accretion rate than the rate derived from the collapse model. Our model shows that BHR71 has an envelope with an age ranging from 1.0x10^4 to 1.75x10^4 years and a total dust mass of 0.22 solar mass.

The gas around and between galaxies, generally too faint to see in emission, can be observed via absorption signatures imprinted on the spectra of background quasars. Low redshift surveys of partially ionized absorbers that are optically thick at the Lyman limit (Lyman Limit Systems) have found that they trace both high (approximately solar) and low ([X/H]<-1) metallicity gas, suggesting these absorption features are produced by both accreting and enriched recycling/outflowing winds. I will discuss the results of metallicity studies of Lyman Limit Systems at z~3.5, when the cosmic star formation rate is largest and the distinctions between inflows and outflows should be more pronounced, and the implications for galaxy formation models and simulations.

We present the results of the age determination study of pre-main sequence (PMS) stars in the Taurus and the Ophiuchus star-forming regions. Ages of PMS stars with 0.5 - 1.5 solar mass were determined from their surface gravities estimated with high-resolution optical and near-infrared spectroscopy. We used equivalent width ratios of nearby absorption lines such as Fe (8204.9A) / Na (8183.3A, 8194.8A) in I-band and Sc (22057.8A) / Na (22062.4A, 22089.7A) in K-band as surface gravity indicators. Since the continuum veiling is nearly uniform over such a limited wavelength range, the equivalent width ratio directly reflects the parameters of the stellar atmosphere of PMS stars. Ages of the pre-main sequence stars were estimated by comparing the derived surface gravities to the evolutionary model. From a comparison of determined ages and near-infrared color excesses, the inner disk lifetime of young stars in the Taurus and the Ophiuchus are estimated to be 2.4 Myr and 1.2 Myr, respectively (Takagi et al. 2014, 2015) which indicate the disk dissipation timescale depends on the environment of the star-forming regions.

Direct imaging/spectroscopy is the means by which we will eventually identify, confirm, and characterize a true Earth twin around a nearby star. While conventional adaptive optics instrumentation has restricted us to primarily imaging only superjovian-mass planets at wide separations, the new suite of dedicated extreme AO systems coupled with advanced post-processing techniques will soon reveal images and spectra for solar system-mass planets. In just one year of science operation, the new extreme AO system GPI has identified a bona fide Kuiper belt analogue to a young Sun-like star, imaged the first methane-rich and ~Jupiter-mass exoplanet, and now potentially has imaged only the second known multi-planet system. I will present the first science results from Subaru/SCExAO, Subaru's cutting edge extreme AO system soon capable of delivering 90+% Strehl in the near IR for moderately bright stars, demonstrating its significant gain in capabilities over conventional systems. In the near-term, SCExAO will be coupled with the CHARIS integral field spectrograph, yielding spectra for young jovian planets down to ~0.1". In a few years, SCExAO will see an even greater gain in capabilities, working in concert with the MEC (MKIDS) detector, allowing it to image and potentially extract spectra for reflected-light planets 10-100 million times fainter than the host star at these and wider separations. I will describe the special long-term opportunity for SCExAO as a precursor survey vehicle/complementary instrument for WFIRST-AFTA and the case for it as a visitor instrument on the Thirty Meter Telescope.

In the last five years we have made remarkable progress in turning superconducting lumped element microwave resonators into the most powerful UV, optical, and near-IR detectors in the world. In this talk I will describe in detail the operating principles of these detectors, called Microwave Kinetic Inductance Detectors, and describe some of the exciting astronomy that we have done with them. I will finish by discussing future possibilities of the technology, including the real possibility that these detectors will be the first ones to detect life on nearby planets.

Debris disks are circumstellar dust disks around main-sequence stars. The dust grains in these systems are supplied continuously by collisions of planetesimals or growing proto-planets. Their evolution is conventionally explained by the steady state collisional cascade model. However, mysterious debris disks have been detected by the AKARI mid-IR all-sky survey. They have large amount of warm circumstellar dust even at late (>1 Gyr) stages, which cannot be accounted for by the conventional theory. Some of them show difference between AKARI 18 micron and WISE 22 micron measurements, which indicate the temporal variations of the disk luminosity between 2006 and 2010 or the existence of small grains showing spectral features in the mid-IR. The small grains indicate recent transient events such as the Moon-forming giant impact because they are blown away from the system in a short (~1 yr) timescale. We are now trying follow-up 8-13 micron spectroscopy of the objects using Subaru/COMICS to clarify them. I would like to mention also the AKARI based study of the zodiacal clouds, a faint debris disk of our solar system, and the future perspective on the debris-disk study using the next infrared astronomical satellite, SPICA.

The direct detection of young and warm extrasolar giant planets in the habitable zone of nearby cool stars is one of the major goals of current ground-based high contrast imaging instruments. To characterize such exoplanets by spectroscopy of their atmospheres requires isolating the planet light from the brighter stellar light, which is challenging due to high contrast at small angular separation. Using high performance small inner working angle (IWA) coronagraphs, it is possible to detect faint companions in the proximity of the stellar source. However, the uncontrolled pointing errors and other low-order wavefront aberrations degrade the rejection capability of these coronagraphs by leaking starlight around the coronagraphic focal plane mask. How well these aberrations upstream of various coronagraphs can be controlled is the focus of my research. To prevent coronagraphic leaks at small IWA, I worked on a concept where within a coronagraph, the low-order wavefront aberrations are sensed at the Lyot plane. The starlight diffracted by the focal plane mask is reflected by the Lyot stop towards a detector, which reliably estimates low-order aberrations present in the wavefront. I called this new sensor a Lyot-based low-order wavefront sensor (LLOWFS), which is now operational on Subaru coronagraphic extreme adaptive optics instrument (SCExAO) at the Subaru Telescope (8.2 meter). On SCExAO, I have validated the closed-loop performance of the LLOWFS for 15 Zernike modes with the Phase-Induced Amplitude Apodization (PIAA) coronagraph and for 35 Zernike modes with the Vector Vortex Coronagraph (VVC) and the four quadrant/eight octant phase masks. Closed-loop pointing residual between 10-3 l/D and 10-4 l/D is obtained in H-band at 170 Hz for slow-varying errors (frequencies < 0.5 Hz) for all the coronagraphs. On the on-sky post-adaptive optics wavefront residuals, correction of 10 Zernike modes are demonstrated with the VVC and the PIAA coronagraph. Under good seeing and for bright target (mH < 2), the low-order control provides a closed-loop pointing residuals of 10-4 l/D whereas under moderate seeing and for targets brighter than mH < 2.5, the low-order control routinely provide a closed-loop residual of 10-3 l/D. In this talk, after introducing the LLOWFS principle in the context of high contrast imaging, I will describe its implementation on the SCExAO instrument followed by the results obtained in the laboratory and on-sky under the extreme-AO (ExAO) and non ExAO regime. As a closing remark, I will explain briefly how the LLOWFS-like technology can benefit the planned ground/space-based ExAO instruments.

Recently, we have performed extensive near-infrared [Fe II] line observations of supernova remnants such as unbiased imaging survey of the first quadrant of the Galactic plane, several imaging observations of additional sources, deep imaging observations of nearby galaxies, and follow-up spectroscopic observations of detected sources. Near infrared [Fe II] line is a good tracer for shocked gas. Some of the observed remnants show interesting features in their spectroscopy. Their motions are investigated in detail using multiplexed spectroscopy such as integral-field unit (IFU) or multi-object spectroscopy (MOS). I will introduce our [Fe II] studies in general and some results of AAT MOS and KNPO IFU observations.

The International Liquid Mirror Telescope (ILMT) project is a joint collaboration between different universities and research institutes in Belgium, India, Canada and Poland, for the design, construction and operation of a 4 meter telescope at the Devasthal Observatory (located in India), that will use the liquid mirror technology. The first part of the talk will introduce the basics of liquid mirrors and the ILMT project itself. I will describe the telescope and its technology particularities, as well as an innovative instrument that has been designed for the measure of its primary mirror optical quality. The second part of the talk will focus on the scientific goals of the project. The ILMT has been designed to perform a photometric variability survey of a narrow strip of sky, making it very suitable for the detection and follow-up of photometrically variable sources such as supernovae and quasars. I will present an estimate of the number of QSOs to be detected within the ILMT survey, and of the expected number of multiply imaged sources among these caused by the presence of a deflector near the lines-of-sight. I will finally explain how this statistical sample of multiply imaged QSOs is intended to be used as a cosmological probe.

The high cadence, long-term PS1 Andromeda monitoring campaign (PAndromeda) yields well-sampled light curves that dramatically improve our understanding of microlensing and variables in M31. We apply stringent masking to the raw data, and employ our dedicated image subtraction pipeline to deliver high quality time-series measurements in the very crowded-field of M31. As a preliminary study, we discover 6 microlensing events in the inner bulge of M31. This demonstrates that deep data with exquisite time-resolution are essential to reveal microlensing events. We further turn the microlensing survey into a variable factory, producing catalogs of ~300 eclipsing binaries, ~ 2000 Cepheids, and ~ 4000 long period variables (LPVs). We select bright eclipsing binaries for spectroscopic follow-up, to obtain a direct distance estimate of M31. We astromatrically align the multi-band Panchromatic Hubble Andromeda Treasury (PHAT) data to our PS1 images, and derive precise period-luminosity relation (PLR) for the Cepheids. The accurate distance and precise PLR will render M31 a distance anchor and provides a firm base to determine the Hubble constant at percent level. To fully exploit the value of PAndromeda, we welcome external collaborators, and can provide PS1 lightcurves with linked HST and Spitzer photometry upon request.

It has been known that there exists excess background light in the near infrared from various data. We report spatial fluctuation analysis of the sky brightness in the near-infrared from observations toward the north ecliptic pole (NEP) by the AKARI at 2.4 and 3.2 μm. As a follow-up study of our previous work on the Monitor field of AKARI, we used NEP deep survey data, which covered a circular area of about 0.4 square degrees, in order to extend fluctuation analysis at angular scales up to 1000". We found residual fluctuation over the estimated shot noise at larger angles than the angular scale of the Monitor field. The excess fluctuation of the NEP deep field smoothly connects with that of the Monitor field at angular scales of a few hundred arcseconds and extends without any significant variation to larger angular scales up to 1000". By comparing excess fluctuations at two wavelengths, we confirm a blue spectral feature similar to the result of the Monitor field. We find that the result of this study is consistent with Spitzer Space Telescope observations at 3.6 μm. The origin of the excess fluctuation in the near-infrared background remains to be determined, but we could exclude zodiacal light, diffuse Galactic light, and unresolved faint galaxies at low redshift based on the comparison with mid- and far-infrared brightness, ground-based near-infrared images.

I will present the rapid scientific and technological expansion taking place at the National Astronomical Research Institute of Thailand, the leading institution for astronomy in South-East Asia. The NARIT science group includes scientists with a broad range of interests spanning from solar system objects, to exoplanets, to stellar physics and cosmology. Alongside with several 50 to 70-cm class telescopes, some of which are fully robotic, the flagship facility is the Thai National 2.4-m Telescope (TNT), equipped with spectrographs and imaging cameras. I will illustrate its characteristics and opportunities for telescope access and collaboration. I will then discuss in particular ULTRASPEC, a visitor instrument built by a Consortium of UK institutes, based on a low-noise, frame-transfer EMCCD with high-quality optics and high-time resolution capabilities: a niche for which no other observatory is similarly equipped in the longitude range of TNT. By using a highly flexible scheme of subarray reading, continuous sampling rates as fast as 4ms can be achieved. I provide examples of new exciting results in areas such as eclipsing binaries, cataclysmic variables, flickering, exoplanet transits, and occultations by the Moon and other solar system bodies. My work in high time resolution at TNT follows in the footsteps of a vast effort carried out over many years with millisecond-resolution in the NIR: I will provide an overview of >1,000 lunar occultations observed from the ESO VLT.

I will report magnetic-field maps inferred from our polarimetric observations of NGC 6334, a region forming massive stars, from 100 to 0.01 parsec scale. NGC 6334 hosts young star-forming sites, where fields are not severely affected by stellar feedback, and their directions do not change much over the entire scale range. The ordered fields lead to a self-similar gas fragmentation: at all scales, there exist elongated gas structures nearly perpendicular to the fields. These indicates the magnetic fields are dynamically important in the fragmentation of NGC 6334. Then, I would try to put forward our explanation towards the commonly observed depolarization of thermal dust emission towards high density regions. With data archives from JCMT and CARMA, we will show that the common proposal, which suggested that dust grains are no longer aligned when Av > 3mag, is insufficient to explain the observations from various scales. We propose line of sight magnetic field structures may significantly lower the observed polarization and may constitute the prime reason for this phenomenon.

Since the launch of the Herschel Space Observatory (Pilbratt et al. 2010), our under- standing about the photodissociation regions (PDR) has taken a step forward. In the band- width of the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imaging REceiver (SPIRE) on board Herschel, ten CO rotational transitions, including J = 4 - 3 to J = 13 - 12, and three fine structure lines, including [CI] 609, [CI] 370, and [NII] 250 μm, are covered. This presentation focuses on the physical conditions of molecular gas probed by the Herschel SPIRE/FTS. Based on the spatially resolved physical parameters derived from the CO spectral line energy distribution (SLED) map and the comparisons with the dust properties and starformation tracers, I will first present our findings at the circumnuclear region of M83 (Wu et al. 2015), and then zoom in toward the molecular cloud near a young open cluster, Trumpler 14, in Carina nebula. I will discuss (1) the potential of using [NII] 250 and [CI] 370 micron as starformation tracers; (2) the reliability of tracing molecular gas with CO (3) the excitation mechanisms of warm CO (4) the possibility of studying stellar feedback by tracing the thermal pressure of interstellar molecular gas.

Polycyclic aromatic hydrocarbons (PAHs) are expected to contain a significant percentage of the carbon budget of the galaxy, and their mid-infrared emission bands are among the strongest and most prominent features in the entire galactic SED. These bands appear sensitive to local environmental conditions, with many specific emission bands showing significant variation in peak wavelength, line profile, and intensity. Understanding the precise reasons behind these variations may allow the use of PAH emission bands as a powerful diagnostic tool for interstellar environments. However, the exact structures and morphologies of PAHs observed astronomically are unknown and poorly understood. The work presented here attempts to decompose two regions of the PAH infrared spectrum, the 3-4 μm range, and the 11-14 μm range, both of which are due to vibration of C-H bonds and are therefore diagnostic of PAH edge structures. Analysing data from AKARI IRC, the strong 3.3 μm emission band is confirmed to be composed of two underlying sub-features at 3.28 μm and 3.30 μm, arising from bay and non-bay sites on PAHs. The remaining emission from 3.4-3.6 μm is also decomposed and contributing factors are discussed. These data are compared with coincident ISO SWS observations from 11-14 μm, diagnostic of the number of hydrogen atoms attached per aromatic ring. Results are discussed in terms of PAH morphologies and molecular stability, together with implications for related unsolved problems in astronomical spectroscopy, the diffuse interstellar bands (DIBs) and anomalous microwave emission (AME).

I will describe a project which is managed by Astronomical Observatory Institute of Adam Mickiewicz University in Poznań, Poland - Global Astrophysical Telescope System. The GATS is primarily intended for stellar high resolution spectroscopy with a global network of robotic telescopes and consists of two telescopes (one in Poland and second in US). The talk will also present project focused on atmospheres of β Cephei and SPB stars in the young open clusters and Galactic field. The pulsation mechanism of proposed variables strongly depends on the abundances of iron-peak elements. From the analysis of high-resolution, high signal-to-noise spectra we will obtain stellar atmosphere parameters and chemical abundances. This will allow to determine the relationships between chemical abundances and pulsational parameters of β Cephei and SPB stars.

Coevolution of galaxies and their central black holes (BH) has been the central theme of much of recent extragalactic astronomical research. Observations of the dynamics of stars and gas in the nuclear regions of nearby galaxies suggest that the overwhelming majority of spheroidal glaxies in the local Universe contain massive BHs and that, wiht some important caveats, the masses of those central BH correlate with the velocity dispersions of the stars in the sheroid and the bulge luminosities. An impressive body of research has been dedicated to understanding the mechanisms responsible for such a fundamental perhaps causal relation. An important component pertinent to those investigations is an accurate census of the basic properties of the cold interstellar medium (ISM) in AGN hosts. The motivation for this is that the cold molecular gas is the basic fuel for star-formation and black hole growth. We present high sensitivity observations taken with the Herschel Space Observatory to measure the cold dust content in a sample of 85 nearby (z <= 0.5) QSOs chosen from the optically luminous broad-line PG QSOs sample and in a complementary sample of 85 narrow-line QSOs chosen to match the redshift and optical luminosity distribution of the broad-line targets. The FIR data are combined with near-infrared and mid-infrared measurements from the Two Micron All Sky Survey and the Wide-Field Infrared Survey Explorer to determine their IR spectral energy distributions which we use to assess aggregate dust properties. We estimate dust temperatures that range between ~20 and 70 K with a median temperature of 45 K respectively, and dust masses between 9 x 10^4 M_sun and 5 x 10^8 M_sun with a median mass of 3 x 10^7 M_sun. We investigate the relation between star-formation rates (SFRs) estimated from the IR luminosities and SFRs determined from measurements of the 11.3 micron PAH. We also compare indicators of AGN strength such as the [OIII] 5007 Angstroms and 5100 Angstroms luminosities with the emission from cold dust measured with Herschel and investigate the differences between the global dust properties of broad and narrow line QSOs. The differences between the cold dust properties of narrow and broad line AGN will be discussed in the context of models that envision that quasar activity is triggered by gas-rich galaxy mergers.

Type Ia supernovae are known as the precise distance indicators that allowed the remarkable discovery of the accelerated expansion of the universe. Despite this astounding feat, there still remain large uncertainties in many of the key issues surrounding these extremely energetic events. These uncertainties, while not being horribly detrimental to their use as distance indicators, hamper the understanding of the far reaching consequences these cosmic factories of heavy elements have on the chemical evolution of the Universe. Type Ia Supernovae can be divided into three distinct phases. The pre-supernova evolution, the explosion itself and the expansion phase. In this talk I will first presents our findings on the progenitor question (pre-supernova phase), then shortly touch on our understanding of the explosion itself, and finally present our work on modelling the spectra resulting from the expansion phase. I will close by giving an outlook of the future of spectroscopic modeling and its consequences for our understanding of pre-supernova evolution and explosion physics.

The nature of Li-rich red giant stars is a decades-old problem that has both challenged and driven advancements in the field of stellar evolution modeling. These relatively rare stars also have important implications for star-planet interactions during the stellar red giant phase. Many of the exoplanets that have been discovered orbit close enough to their host stars that they cannot escape engulfment during their stars' lifetimes, and massive, engulfed planets could replenish the abundance of Li in a red giant's atmosphere. In this talk, I will summarize what we have learned about the abundance of Li during stellar evolution and which Li-rich stars may be explained by known astrophysical processes. I will highlight stars that defy our current understanding, focusing on a well-characterized Li-rich star in the open cluster NGC 6819, and will discuss future work needed to understand these 'puzzlers'.

Understanding the influence of black hole growth on star formation and galaxy evolution over cosmic time scales requires a census of the AGN population, in particular in respect to their black hole masses and accretion rates. We present such a census of the active black hole population from z=0 to z=2, with an emphasis on 1 < z < 2, by studying the bivariate distribution function of black hole mass and Eddington ratio. This allows to clearly disentangle the AGN downsizing phenomenon, present in the AGN luminosity function (AGN LF), into its physical processes of black hole mass downsizing and accretion rate evolution. Compared to z = 0 we find a distinct change in the shape of the black hole mass and Eddington ratio distribution function, consistent with downsizing in black hole mass. The active fraction or duty cycle of type-1 AGN at z~1.5 is almost flat as a function of black hole mass, while it shows a strong decrease with increasing mass at z = 0. We are witnessing a phas e of intense black hole growth, which is largely driven by the onset of AGN activity in massive SMBHs towards z = 2. We discuss the implications of these observational constraints for theoretical models of galaxy evolution and black hole growth.

GRAMORs are strongly magnified lensed images with small distortion. One example is discovered in a cluster MACS J1149.5+2223 in 2009. We investigate the lens statistics of GRAMORs in detail. Assuming NFW profile for our sample of clusters, we calculate the expected number and redshift distribution of GRAMORs using parameters given by COSMOS data for the number density of the background galaxy. Our model of the cluster placed at z= 0.544 and the background galaxies with WMAP 5 cosmology predicts the redshift of GRAMOR at z ~= 1.49 which is close to the observed z=1.4906. It is found that the probability distribution function of GRAMORs depends strongly on the existence of the dark energy and maybe useful for constraining the nature of dark energy.

How can a Universe ruled by thermodynamics and its infamous Second Law generate structure, something which we witness on a daily basis? Francois Roddier recently published a book entitled "La Thermodynamique de l'evolution". It is a fascinating read in which he introduces recent advances in the field of thermodynamics of open systems and applies them to the apparition of structure, life, evolution and the history of our civilization. In fact in open systems, there turns out to be a Third Law which was only formalized as recently as 2003! I will introduce the general concepts that drive the emergence of structure in thermodynamics, and show through a wide variety of examples that the patterns and processes of these non-linear dynamical systems are recurrent and indeed very general. One such example is of course biological evolution, which provides an easy-to-grasp analogy for the evolution of Astronomy in the last century. Having been hired on a joint appointment between Gemini Observatory and Subaru Telescope with the idea of fostering collaborations, I quickly realized that each observatory's culture, projects and even motivations would make such a task difficult using traditional means. This situation led me, using our recently acquired understanding of open systems, to develop - from first principles, as it were - a new type of lightweight and highly adaptable collaborative structure, based on the concept of meta-consulting. I am proposing to implement this concept around adaptive optics on Mauna Kea in the CHAOPTIX experiment. I will describe the way CHAOPTIX might operate, but I will seek your input as to how both observatories and their staff will most benefit from any potential collaborations, not just limited to adaptive optics. The seminar will lead into an open discussion with the goal of gathering both momentum and feedback so as to structure and tailor the CHAOPTIX concept to the needs of its users within the paradigm of open and distributed systems.

We have been targeting ~10 proto-clusters and the general fields covering the peak epoch of galaxy formation (1.4 < z < 3.7) through our Mahalo-Subaru project. It employs unique sets of narrow-band filters on wide field instruments (Suprime-Cam and MOIRCS) to map out line-emitting star-forming galaxies (H-alpha, [OIII], and [OII] emitters) associated to the proto-clusters or in narrow redshift slices in the general field. We present that all of our targets show prominent large-scale structures in and around them, indicating that they are still in vigorous assembly phase. Moreover, we show that star formation activity in the cluster cores is very high at z~2 involving a significant fraction of dusty star-bursting galaxies. The integrated star formation rate in the cluster core normalised by the dynamical mass drops sharply as time progresses as (1+z)^6, and the peak of star formation activity is shifted outwards to surrounding lower density regions, indicating the ``inside-out'' growth of galaxy clusters. Spectroscopic follow-up observations reveal that the proto-cluster galaxies at z~2 tend to have much higher ionization states than present-day counterparts, characterized by the presence of strong [OIII] emission lines. Moreover, we find that their gaseous metallicities in dense environment are systematically higher than those in the general fields at z~2. This is probably due to some environmental effects on the gaseous inflow/outflow processes. I will then introduce our up-coming larger project SWIMS-18 which will start in early 2016 to expand and enhance the current successful Mahalo-Subaru project. I will finally touch on our future prospects on galaxy anatomy with TMT.

Revealing galaxy properties at z~1-2, where galaxies are in the most active phase, is important to understand the formation and evolution of galaxies. The chemical properties of galaxies such as gas metallicity are also important parameters to examine the galaxy growth, because metallicity traces the past star-formation activity including gas inflow and outflow. However, a large NIR spectroscopic observation is required to measure the gas metallicity of galaxies at z~1-2 by using the rest-frame optical emission lines. Recently, we conduct large NIR spectroscopic surveys with a wide-field NIR spectrograph on the Subaru Telescope, Fiber Multi Object Spectrograph (FMOS). In the FMOS/GTO survey, we obtained significant Ha detections from ~340 star-forming galaxies at z~1.4. In the FMOS cosmological redshift survey (FastSound), which is shallower survey than the FMOS/GTO, we detect Ha emission lines from ~4000 galaxies at z~1.4. We measure the gas metallicity from the [NII]6584/Ha emission line ratio of composite spectra in various stellar mass and star-formation rate bins. The resulting mass-metallicity relation at z~1.4 is between those obtained in previous studies at z~0.8 and 2.2. No clear dependence of the mass-metallicity relation on star-formation rate is found, which is not in agreement with the extrapolation of the local fundamental metallicity relation. We detect the significant [SII]6716,6731 emission lines from the composite spectra. We estimate nitrogen-to-oxygen abundance ratio (N/O) from the N2S2 index, and found that the N/O in galaxies at z~1.4 is significantly higher than the local value at a fixed metallicity. Our sample at z~1.4 with the metallicity recalculated taking into consideration the N/O enhancement is in good agreement with the extrapolation of the local fundamental metallicity relation. This result is an excellent test case for near-future surveys with a next-generation very wide-field multi object spectrograph on the Subaru Telescope, Prime Focus Spectrograph (PFS).

We have performed archaeological surveys of nearby galaxies using the Subaru telescope from the two perspectives in order to untangle how halos of galaxies form. The one is to understand fine structures such as stellar population, luminosity functions of stellar streams, metallicity gradients, the distribution of satellite galaxies through wide-field observations of the Milky Way and the Andromeda galaxy (M31). The other one is to understand universal formation scenario of halos through comparisons these structures which we have found in the Local Group galaxies with structures of halos in the Local Volume galaxies, that is, galaxies beyond the LG. Then, we have been conducting the wide-field and deep photometric surveys of M31's halo (S14B) and the NGC4631 group (S14A, S15A) with HSC from last year. Subaru/HSC makes us to draw a less-contaminated stellar density map based on Red Clump stellar populations of M31's halo, and we can detect some faint substructures in our HSC field which are not found in the previous CFHT/MegaCam survey as a preliminary result. On the other hand, the NGC4631 group is an on-going interacting system, and is important to understand the origin of the verity of galactic halos. Although the observation of S14A was under the very poor condition, we newly detect 8 dwarf galaxies around NGC4631 galaxies based on visual inspection. We find that a positive correlation between total absolute magnitude and half-light radius of these dwarf galaxies is similar to the one of the Local Group. In this seminar, I'd like to introduce the current status of our galactic archaeological study.

We present results from Subaru/FMOS NIR spectroscopy for 118 [OII] emission line galaxies at z=1.47 and 1.62 in the Subaru Deep Field. We use six nebular emission lines in the individual and composite spectra in the rest-frame optical to investigate physical conditions of the ISM in the star-forming galaxies at z~1.5. We have found that the [OII] emitters have strong [OIII] emission lines, showing the [OIII]/[OII] ratios larger than normal star-forming galaxies in the local Universe. There is a dependence of the line ratio on stellar mass in the sense that less massive galaxies have larger [OIII]/[OII] ratios. With evidence that the electron density estimated from the flux ratio of [SII] doublet is consistent with the local galaxies, the high ionization parameter of galaxies at high redshifts is likely to be attributed to harder radiation field by young stellar populations and/or the increasing number of ionizing photon from massive stars. Moreover, we have found that there is a tight correlation between Halpha and [OII], which suggests that [OII] can be a good indicator of star formation rate for galaxies at z~1.5. The line ratios of Halpha/[OII] are consistent with those of the local galaxies.

8m-class telescopes are important ingredients in follow-up observations of nearby supernovae (SNe), which can provide data with observing modes or at epochs which are difficult to obtain by smaller telescopes (near-infrared, high resolution, polarimetry, late phases). I will show some results we have obtained with the Subaru and other 8m-class telescopes about natures of supernovae. The topics will include discovery of dust formed in SNIIn 2010jl (in NIR by IRCS+AO188) and the detailed nature of these dust particles, discovery of oxygen-rich matter near the center of a peculiarly faint SN Ia 2010lp (in a late phase) which challenges to any existing theories, detailed follow-up observations of an enigmatic SN 2008ha-like SN Ia 2010ae (for which we find diversity within the class through the late-phase observations), and SN Ia 2008J having exploded within dense CSM (where the CSM properties are constrained through the high-resolution observations), and natures of SNe associated with Gamma-Ray Bursts. Aims and some preliminary results from ongoing Subaru observing programs will also be presented.

In decades, the connection between galaxy evolution and the growth of supermassive black holes (SMBHs) has been one of the main topics in extragalactic research. The tight correlation of black hole mass, M_BH, with galaxy properties, e.g., sigma, suggests the coevolution of galaxies and SMBHs. Various observational studies have been devoted to investigating the nature of the coevolution, e.g., the redshift evolution of the M_BH-sigma relation mainly using type-1 active galactic nuclei (AGNs). The connection between on-going star formation (SF) and AGN activities is also one of the observational signatures, revealing the connection of the growth of stellar mass and the BH growth at the observed epoch. Recently, we investigated the relation between SF and black hole accretion luminosities, using a sample of 689 type-2 AGNs at 0.01 < z < 0.22, which are detected in the far-infrared (FIR) surveys with AKARI and Herschel. By estimating AGN luminosities from narrow emission lines, we found a positive linear trend between FIR (SF) and AGN luminosities over a wide dynamical range. This result appears to be inconsistent with recent reports that low luminosity AGNs show essentially no correlation between FIR and X-ray luminosities, while the discrepancy is likely due to observational biases. In this seminar, I would like to talk about the AGN-SF relation based on above results, and discuss limitations of studying the connection between AGN and SF using current available facilities.