Submitted Abstracts
Stellar Physics and Galactic Archaeology with wide-field survey and high-resolution spectroscopy
By: Wako Aoki
Abstract: Wide-field spectroscopic surveys provide with statistics of a variety types of stars and useful sample to investigate specific issues on stellar physics and Galactic Archaeology. The spectroscopic survey telescope LAMOST completed the first five-year regular survey. We have been conducting follow-up high-resolution spectroscopy with the Subaru Telescope. We will show recent results from this project, including 1)Li-enhanced stars, which shed new light on low-mass stellar evolution of red giants, 2)r-process-element enhanced stars as a useful tracer of formation process of the Milky Way halo. In the TMT era, such studies will be extended not only to wider range of the Milky Way but to nearby galaxies by combining wide-field survey with 8-10m class telescopes (e.g. the Subaru Telescope with PFS) and high-resolution spectroscopy with TMT.
Co-Authors: W. Aoki, G. Zhao, H-n. Li, T. Matsuno, J. Shi, Q. Xing, J. Zhao, T. Suda, S. Honda
Infrared variability of the supermassive black hole at the Galactic Center
By: Zhuo Chen
Abstract: The Galactic center hosts the closest example of a supermassive black hole to the Earth, offering us a unique opportunity to study black hole accretion physics. While nearby, observations of Sgr A* still requires both high spatial resolution and high sensitivity. Adaptive optics enabled the discovery of the infrared counterpart to the supermassive black hole at the Galactic center in 2003, and observations of the black hole in the near-infrared have been made ever since. In this talk, I will present new results that extend the measurements of the near-infrared behavior of Sgr A* going back to 1998. This has allowed us to examine the activity of the black hole for over 20 years. I will also discuss how this year, the black hole's activity may have changed when compared to the historical data. Finally, I will also discuss the leap in understanding we will gain with TMT. The greatly improved sensitivity of TMT enables monitoring Sgr A* infrared emission with timescale well below 1 second, to investigate the variability physical scales much smaller than previous studies and understand the accretion flow physical mechanism.
Co-Authors: Zhuo Chen, E. Gallego-Cano, T. Do, G. Witzel, A. M. Ghez, R. Schodel, B. N. Sitarski, E. E. Becklin, J. Lu, M. R. Morris, A. Ciurlo, A. Dehghanfar, A. K. Gautam, A. Hees, M. W. Hosek, Jr., S. Jia, A. C. Mangian, G. Martinez, K. Matthews, S. Sakai
UV and NIR size of the low mass field galaxies: the UV compact galaxies
By: Cheng Cheng
Abstract: Most of the massive star forming galaxies are found to have “inside-out” stellar mass growth mode, which means the inner part of the galaxies are mainly consist with older stellar population while the star forming in the outskirt of the galaxy is still ongoing. The high resolution HST images from Hubble Deep UV Legacy Survey (HDUV) and Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) projects with the unprecedented depth in both UV and NIR bands are the perfect data sets to study the forming and formed star distribution directly. We select the low redshift (0.05 < zspec < 0.3) galaxy sample from the GOODS-North field where the HST UV and NIR images are available. Then we measure the half light radius in UV and NIR bands, which are the indicators of the star formation and stellar mass. By comparing the UV and NIR half light radius, we find the high mass galaxies have the “inside-out” growth mode, which is consistent with the previous results. Moreover, the HST UV and NIR images reveal some of the low mass galaxies have the “outside- in” growth mode: their images show a compact UV morphology, implying a ongoing star formation in the galaxy center, while the stars in the outskirt of the galaxies are already formed. The two modes transit at stellar mass about 109M⊙. We also try to identify the possible neighbours galaxies from SDSS data, which represents the massive galaxy sample. We find that all of the spec-z selected galaxies have no massive galaxy nearby. Thus the outside-in mode we find in the low mass galaxies is not likely originated from the environment.
Co-Authors: Kevin Cong Xu, Lizhi Xie, Zhizheng Pan, Wei Du, Xu Shao, Shumei Wu, Roger Leiton, Gustavo Orillana, Jiasheng Huang, Sophia Yu Dai, Paulina Assmann, Nicole Araneda
Space and Ground-based Searching for Earth 2.0s
By: Jian Ge
Abstract: The 2019 Nobel prize in Physics was awarded to Drs. Mayor and Queloz for detection of the first giant planet orbiting a sun-like star, 51 Peg. This has concluded the first phase of mankind’s search for extrasolar worlds. We can now answer that we are NOT the only planet in the universe. There are thousands of known extrasolar worlds out there. All of them show very different characteristics from our own system. The next natural phase of mankind’s search for extrasolar worlds is to look for Earth-like habitable worlds orbiting sun-like stars, called Earth 2.0s, and possible life signatures on them. I will first summarize the current status, including work carried out by my group, in this search, then present a four-year space mission concept, called Super Kepler, to monitor over 200,000 sun-like stars in the original Kepler and its surrounding 1800 square-degree field (17 times the Kepler field) with a seven 30cm telescope array from year 2025 to 2029. The goals are to detect over 10 Earth 2.0s and determine the occurrence rate of Earth 2.0s for the first time. The extremely weak signals produced by these Earth 2.0s creates major challenges not only in detecting them with space high precision photometry missions, but also in characterizing them with ground-based spectroscopy facilities. Our study shows that only future 30-meter class telescopes equipped with a high stable, high precision, and high-resolution optical spectrograph can effectively characterize these elusive planet signals to measure their masses and densities, which can eventually determine their habitability. Specifically, the combination of the Super Kepler space mission with the TMT High Resolution Optical Spectrograph led by China’s team will provide the unique and most powerful next generation facilities to detect Earth 2.0s and help address mankind’s fundamental questions: “Are we alone in the universe?” and “Where did we come from?”.
Ground-based and Earth Orbiting Observational Support of NASA Solar System Missions: Past, Present, and Future.
By: Thomas Greathouse
Abstract: The exploration of our Solar System relies on both well instrumented spacecraft sent to make up close observations of targets such as planets, moons, asteroids and comets and a rich and diverse array of ground-based and Earth orbiting observatories. Each type of mission or observatory has their own unique advantages and disadvantages for the study of these temporally varying targets of interest. Through the cooperation of all of these facilities the scientific community has expanded our understanding of the formation and evolution of our solar system in ways no one observatory or mission could ever do on their own. In this talk we will highlight past and present combinations of missions and ground and Earth orbiting support observations which leverage the advantages of all these systems, removing limitations of any individual observatory. We will then look forward to the future where new facilities such as JWST, TMT, GMT, and the ELT exist and ask how they will affect our current paradigm of mission support.
Co-Authors: Glenn Orton, Leigh Fletcher, Vishnu Reddy, Tracy Becker
IMF Studies in the TMT era
By: Priya Hasan
Abstract: The Initial Mass Function in young star clusters has been an age old problem in Astronomy. The problem of membership, binary resolution, variability, etc have led to a variety of conflicting conclusions. In the TMT Era and with the future releases of Gaia and new infrared data, it is expected that many of these issues can get better resolved. Precise astrometry and precise parallaxes will also resolve issues like multiplicity of stars and help identify binary sequences. With clean, precise color-magnitude diagrams it would be possible to get better estimates of the IMF at the sub-stellar level. As a special case, we shall compare the IMF and mass segregation of 9 young clusters with the Gaia DR2 release. I shall use these details to help define the science case, requirements and the expected precision in answering possible questions about the IMF of star clusters in terms of astrometry, photometry and high resolution spectroscopy.
Probe the early growth of massive black holes with the Subaru Hyper Suprime-Cam wide field imaging
By: Wanqiu He
Abstract: The black hole mass function (BHMF) and Eddington ratio distribution function (ERDF) at z > 3 are the main demographic constraints to statistically unveil the early growth of massive black holes. The HSC-SSP enables us to select a large sample of z=4 quasars around the knee of the luminosity function, i.e., the typical quasars at the epoch. Utilizing the 58 identified z~4 quasars at 20
Co-Authors: Masayuki Akiyama
Maximum Likelihood Density Reconstruction of the High Redshift Cosmic Web
By: Benjamin A Horowitz
Abstract: In this talk, I will present the Tomographic Absorption Reconstruction and Density Inference Scheme (TARDIS), a new chrono-cosmographic analysis tool for understanding the formation and evolution of observed cosmic structures at high redshift (z∼2.5). Using a maximum likelihood framework, we are able to jointly reconstruct the density as traced by overlapping galaxy fields and lyman alpha forest, by utilizing a fast non-linear gravitational model to reconstruct the initial density field of the observed regions. Applying this technique to mock Lyman-α forest data sets that simulate an overlapping galaxy and background source catalog from TMT, we are able to infer the underlying matter density field at observed redshift and classify the cosmic web structures with high accuracy. As an output of this method, we are able to further evolve the inferred structures to late time (z=0), and also track the trajectories of coeval z=2.5 galaxies to their z=0 cosmic web environments.
TMT Early-Career Initiative: Supporting the Next Generation of Leaders in Astronomical Research and Technology Development
By: Lisa Hunter
Abstract: The TMT Early-Career Initiative (TECI) is a program that directly supports the TMT partnership by engaging graduate students, postdoctoral researchers, and other professionals at early career stages with the project. TECI includes an annual workshop which stimulates involvement in TMT projects and new collaborations. TECI focuses on skills valued by the telescope community, such as instrument design, project management, and teamwork. After the workshop, TECI attendees may also work as a small team on a TMT related project, which allows them to put into practice what they learned at the workshop and to broaden their connections within the TMT community.This presentation will provide an overview of TECI and outcomes to date.
Co-Authors: Lisa Hunter, Nicholas McConnell, Austin Barnes, Renate Kupke, Warren Skidmore, Jessica Lu, and Scott Roberts
Seeing common or rare AGN with TMT
By: Kohei Ichikawa
Abstract:
TMT will give us two new eyes: One is the eye with the exquisite spatial resolution. TMT will spatially resolve the tiny structures/components surrounding the SMBHs in the local universe. The second is the eye of its exquisite sensitivity. The wide-field surveys have been finding very interesting, but very rare AGN populations. Their discoveries have been based on the imaging surveys using 8m class telescopes and obtaining the spectroscopic information is still challenging because of its faintness down to ~26, which limits our understanding of the important parameters such as redshift, and therefore the luminosities, stellar-mass, black hole masses of such interesting sources. TMT will easily resolve this issue by obtaining the spectroscopic information of those sources thanks to its sensitivity. In my talk I will review our recent projects in the local (z<0.1) and the relatively higher-z universe (z>1), and how TMT will easily give us imaging/spectroscopic views thanks to its great spatial resolution/sensitivity.
Wide-field near-infrared surveys of high redshift galaxies and TMT follow-up
By: Akio K Inoue
Abstract: I will present a forecast of very high-z (z>10) galaxy surveys with future wide-field near-infrared imaging facilities such as Euclid, WFIRST, ULTIMATE-Subaru and WISH-like satellites. The galaxies found in these surveys will be followed-up with TMT and I will also discuss its feasibility.
Young Stellar Populations in the Centeral 0.5 pc of Our Galaxy III: The IMF of Dynamical Sub-group
By: Siyao Jia
Abstract: We measure the 3D kinematic structures of the young stars at the central 0.5 parsec of our Galactic center using 10m Keck telescope with time baseline from 1995 to 2015.
Using these high-precision astrometric measurements of positions and proper motions, plus radial velocities from literature, we are able to constrain the orbital parameter for each young star.
Our results will clearly show the significant clockwise stellar disk as has been proposed before but with a better disk membership measurement.
Based on their disk membership, the young stars can be divided into disk stars and off-disk stars.
A Bayesian inference method is applied to disk and off-disk stars separately to derive the stellar properties, including mass, for these two dynamical sub-groups.
It will be the first time that stellar populations are analyzed and compared between disk and off-disk stars, which may allow us to distinguish between different models of star formation around the supermassive black hole at our Galactic center.
Co-Authors: Jessica R. Lu, S .Sakai, A. K. Gautam, T. Do, K. Kosmo, M. W. Hosek Jr., M. Service, A.M. Ghez, M.R. Morris, and K. Matthews
Galaxy quenching with PFS, ULTIMATE and TMT
By: Tadayuki Kodama
Abstract: We have been tracing the cosmic large scale structures hosting galaxy clusters/groups since z=1.7 to 0.4 with HSC (HSC^2 survey), and constructing a unique sample of recently quenched galaxies (RQGs) along the structures. With a systematic spectroscopic follow-up program with PFS (PFS^2 survey) on the unique samples of rare objects such as distant clusters and RQGs we wil investigate the growth of galaxy structures with cosmic times, and unveil the star formation histories of galaxies therein, such as biased galaxy formation and environmental quenching as well as the intrinsic evolution of galaxies related to their mass.
With ULTIMATE-Subaru and TMT we can go further back in time and and characterize the first formation of massive quiescent galaxies which will give strong constraints on the speed of galaxy formation in the early Universe.
Co-Authors: HSC^2, PFS^2, and ULTIMATE-Subaru teams
TMT synergies for the first billion years of the Universe
By: Girish Kulkarni
Abstract: The first billion years of the Universe are witness to the emergence of galaxies and the process of reionization. In spite of this importance, this crucial epoch of cosmic history has so far remained largely unexplored. Changing this situation is one of the most important science cases for facilities such as TMT, SKA, and JWST. Synergies between these upcoming observatories will revolutionise our understanding of the epoch of galaxy formation and reionization. In this talk, I will discuss the SKA roadmap and the SKA-TMT synergies relevant to the epoch of galaxy formation and reionization, such as absorption-line studies, first stars, and faint AGN.
Finding black holes and neutron stars with TMT
By: Casey Lam
Abstract: The Milky Way is predicted to harbor 100 million neutron stars (NSs) and stellar mass black holes (BHs); however, these estimates are uncertain by orders of magnitude. To date, only a few thousand NSs and a few dozen BHs have been found, in very particular systems (NSs as pulsars; NSs and BHs in binaries). Gravitational microlensing is one of the only ways to find isolated BHs or NSs as it passes in front of a background star and temporarily magnifies the star's flux and distorts its position. Thousands of microlensing events are detected each year by wide-field photometric surveys and only a few dozen will be due to BHs or NSs. We present a new simulation called PopSyCLE (Population Synthesis for Compact object Lensing Events), which models microlensing events in the Milky Way. With PopSyCLE we show TMT has the ability to measure the centroid shifts of BHs and NSs, which is not currently possible, and the combination of WFIRST and TMT will allow us to precisely measure the masses of O(1000) BHs and NSs. This will allow us to accurately measure the masses and kinematics of isolated BHs and NSs, giving insight into their formation channels.
Co-Authors: J. R. Lu, M. W. Hosek, Jr., W. A. Dawson, N. R. Golovich
Method for observational constraints on interacting dark energy from galaxy clusters virial equilibrium states for the TMT
By: Morgan Le Delliou
Abstract: The nature of the dark sector components of the universe still remains one of the largest unknown. Among many possibilities, it has been speculated that dark matter and dark energy may be more tightly coupled than usually thought, one component interacting with the other.
Here, we continue to explore the possible dark sector interaction through means of the Layzer-Irvine equation together with a model of an interacting dark sector applied to clusters of galaxies.
We have selected galaxy clusters which have their mass profiles determined by gravitational lensing effect (optical observations) and have their intracluster gas temperatures measured from X-ray observations and spectral fit found in the literature. Using a simple model based on semi-analytical simulations, we derived a putative dynamical evolution of the clusters and used it to estimate the coupling parameter of the dark sector interaction.
Through a Bayesian analysis, we obtain a $3 \sigma$ detection of the interaction strength for 11 clusters at $-0.027 \pm 0.009$ which translates in a compounded universal equilibrium virial ratio, $U/T$, of $-0.61^{+0.04}_{-0.03}$.
We note that the X-ray temperature determination is sometimes inconsistent, depending on the instrument and/or methodology used. The level of detection and these inconsistencies call for caution. We expect that future observations will give us a clearer indication of an eventual dark sector interaction.
Co-Authors: M. Le Delliou
Mapping High-Redshift Large-Scale Structure with Subaru PFS
By: Khee-Gan Lee
Abstract: The Subaru Prime Focus Spectrograph (PFS) is a massively multiplexed (2400 fibers) wide-field (1.2 sq deg) optical-NIR spectrograph currently under construction for the 8.2m Subaru Telescope. I will briefly outline its capabilities before describing the 300-night Subaru Strategic Program (SSP) survey being planned for near-field cosmology, galaxy evolution, and cosmology. Then, I will focus on the density reconstruction techniques being developed in order to fully exploit the rich large-scale structure information that will be mapped by the high-sampling rate galaxy evolution survey (0.7
Formation and evolution history of the Milky Way: the chemo-dynamical view
By: Haining Li
Abstract: Stars in the Milky Way halo and nearby galaxies are considered fossil records that have been produced during the early Galactic formation and evolution. Large-scale survey projects in the past decade have achieved great progresses in providing important clues to the underlying astrophysical processes involved, through investigating the position, velocity and abundance distributions of stars, including stars in the stellar streams and moving groups, extremely metal-poor stars, chemically peculiar stars, etc. However, there are still a number of key questions to be addressed, e.g., the formation of low-mass stars from metal-free clouds, nucleosynthesis in the early universe, origins of building blocks of the Galactic halo, etc. With ongoing and future survey projects and TMT (WFOS and HROS), we will be able to expand the scope of observation to stars at much fainter and outer region, whose kinematic information together with chemical tagging would help better understand the evolution of the Galaxy and its merging history.
TMT and Variable stars as well as the Structure and Evolution of the Core of the Milky Way
By: Zhiping Li
Abstract: Through observational studies of pulsating variable stars, we can obtain effective information on luminosity, distance, age, metal abundance and space motion. Therefore, pulsating variable stars are very useful tracing objects. Many valuable results on the structure and evolution of the core of the Milky Way and its central massive black hole have been obtained through analysis and observations of the classic Cepheid variable stars, Mira variable stars, Type II Cepheid variable stars and RR Lyrae variable stars in OGLE Surveys, VVV Surveys, HST Observations, and other infrared surveys. Because of its powerful light concentrating ability and superior high resolution ratio, TMT telescope will enhance the infrared photometry as well as infrared medium-high dispersion spectroscopy observation studies of pulsating variable stars in the core of the Milky Way to 24 magnitude（In J K H ）or higher, which is a milestone in the study of the structure and evolution of the core area of the Milky Way and the characteristics of its central massive black hole.
Transformative Science with an WFOS IFU
By: Christopher Martin
Abstract: A slicer-based WFOS Integral Field Unit will deliver extraordinary science capability at a modest incremental cost for a wide range of topics in galactic and extragalactic astrophysics. We highlight some of these using early KCWI results (as well as MUSE) as a guide. In particular, WFOS-IFU will revolutionize our understanding of the physical conditions in the Circum-Galactic Medium (CGM) and the Intergalactic Medium. It will probe the fundamental role of gas, metal, and energy flows into and out of young galaxies that may control their formation and evolution.
Small Solar System Bodies and Interstellar Objects: Synergies Between LSST, JCMT and TMT
By: Karen Jean Meech
Abstract: The discovery and characterization of the first interstellar object (ISO) in October 2017 [1] has opened a new area of study on a broader perspective of planetary system formation [2]. To date, there have been over 120 scholarly publications on this object. ‘Oumuamua was discovered during the course of routine NEO sky surveys, already past perihelion and moving rapidly away from Earth. Within the time it took the community mobilize telescope assets to conduct observations it had faded significantly, thus reducing the quality and amount of data. LSST will detect ~ 1 ISO per year. Observations of nearly inactive long period comets, called Manx comets [3], like ISOs will be difficult to characterize. Visible and infrared photometry, astrometry, adaptive optics imaging, and spectroscopy will allow for characterization of the size, shape, rotation state, surface composition and presence of volatiles. For ISOs this allows us to study the physical and chemical processes during planet formation in other star systems. Characterization of Manx mineralogy will distinguish between models of solar system formation. This paper will present the results from a workshop held in Aug. 2019 in Hawaii to determine the optimal strategy to develop legacy data sets for these unique objects.
[1] Meech et al (2017). Nature 552:378-381.
[2] Raymond, S. N. et al. (2018). MNRAS 476:3031-3038.
[3] Meech, K. J. et al (2016). Sci. Advances id. 1600038.
Co-Authors: K. Meech, M. Buie, E. Bufanda, J. Castillo-Rogez, L. Denneau, D. Farnocchia, O. Hainaut, H. Hsieh, R. Jedicke, J. Keane, J. Kleyna, M. Micheli, D. Tholen, R. Wainscoat, R. Weryk, B. Yang
TMT and Small Body Missions
By: Karen Jean Meech
Abstract: Discovery class missions have limited budgets for instrumentation. For small body missions this means that there is significant characterization that should be done from the ground for mission planning and for in-situ observation science context. Proteus is a proposed origins mission that uses isotopes to explore the origin of primordial volatiles in the inner solar system–addressing the question of habitable world formation. The mission targets two main belt comets which record the history of migration in the early solar system and are small enough to preserve primordial volatile signatures. Comet Interceptor is a new ESA F-class mission that targets (an as of yet, undiscovered) pristine long period comet. This mission will combine an agile set of spacecraft waiting in Earth’s L2 position for a suitable comet discovery. NASA’s Lucy mission also samples the diversity of small bodies through an exploration of 6 Trojan asteroids. These missions will (or are proposed to) launch in the late 2020’s and have encounters in the 2030’s. The synergy of TMT with these missions, and with other facilities that will be available in the 2030’s will be presented.
Co-Authors: K.J. Meech
TMT and Chinese Space Station telescope synergies for gravitational lensing
By: Nicola Rosario Napolitano
Abstract: Strong Gravitational lensing is a very powerful technique to study dark matter in galaxies and to investigate dark matter halo substructures up to high redshift. Taking advantage of the super-high resolution allowed by space missions, like the Chinese Space Station Telescope, we will collect an unprecedented number of strong lenses spanning a wide range in mass and redshift. The superb resolution of the TMT will then allow us to follow-up a golden sample to rebuild the substructure halo mass function in different redshift slices and provide a unique test for the Lambda Cold Dark Matter halo mass predictions.
MICHI: Status Update
By: Chris Packham
Abstract: We present the current status of MICHI, a possible early generation thermal-infrared (TIR) instrument for the TMT. We focus on the primary science drivers of exoplanets (formation, atmospheric characterization, and direct TIR imaging), and active galactic nuclei, as well as enabling technologies.
Co-Authors: Chris Packham, Mitsuhiko Honda, Mark Chun, Itsuki Sakon, Matthew Richter, Yoshiko Okamoto, Hirokazu Kataza, Christian Marois, Michael Meyer Manoj Puravankarak, Jayne Birkby, Ian Crossfield, Thayne Currie, Thomas Greathouse, Gregory Herczeg, Kohei Ichikawa, Hanae Inami, Masatoshi Imanishi, Enrique Lopez-Rodriguez, on behalf of the MICHI Science & Instrument Team
The Extremely Large Telescope
By: Paolo Padovini
Abstract: I will present an overview of the current status of the Extremely Large Telescope
(ELT) project, concentrating on recent developments. I will then briefly discuss the
many multi-wavelength synergies with other facilities.
Co-Authors: Michele Cirasuolo
Measuring Cosmological Parallaxes with TMT
By: Michael Jay Pierce
Abstract: The current tension between the expansion rate (H0) derived from cosmological models and measurements of Type Ia supernovae (SN) and Baryon acoustic oscillations plus Cosmic Microwave Background (BAO) verses local measurements of H0 has reached the point where a consideration of non-standard cosmographic techniques seems prudent. Over the next decade, high resolution imaging with AO on the ELTs will provide the capability to measure the optical positions of extragalactic systems to an unprecedented accuracy. This will permit a measure of the transverse co-moving distances for strongly lensed systems that result from our secular motion with respect to the CMB rest frame (this is the “Cosmological Parallax”). This measurement is interesting in that it is: magnified by gravitational lensing, independent of both SN and BAO, is geometrical, and the secular signal increases with time. Some recent simulations of this phenomena in the context of the TMT will be presented.
Mysteries of the Odd-Z Elements
By: Catherine Pilachowski
Abstract: Unlike the alpha-elements, the nucleosynthesis of the odd-Z elements (F, Na, Al, P, Cl, K, and Sc) is poorly understood. Nonetheless, odd-Z elements have much to tell about the chemical evolution of stellar populations. Odd-Z elements are produced by a variety of processes; for several, the predictions of chemical evolution models do not account for the observed abundances. Abundances of odd-Z elements can constrain the relative contributions of different nucleosynthesis sites, and may also reveal exotic nucleosynthesis processes occurring during explosive nucleosynthesis. Diagnostics include specific element ratios, but also matching the full pattern of abundances, including the amplitude of the odd-even effect and the slope of abundance vs. atomic number for even and odd elements. Such an analysis is the next step in precision needed to understand the chemical evolution of stellar populations in more detail.
Some of the light, odd-Z elements are easily observed from optical spectra (Na, Al, Sc), but abundances of all, plus Mg, Si, S, and Ca, can be determined from high resolution spectroscopy in the infrared. Our current knowledge of the abundances of light, odd-Z elements will be reviewed, along with opportunities for infrared spectroscopy with TMT to reach beyond the local Milky Way.
Co-Authors: Zachary Maas (Indiana University)
Chinese Participation to the SKA
By: Bo Qin
Abstract: I will give an overview of the Chinese participation to the Square Kilometre Array (SKA) project.
The Coeval of AGN and Star Formation in Radio Galaxies and the Effect of Environment at z ~ 1
By: Lu Shen
Abstract: Using imaging from the Very Large Array at 1.4GHz and Spitzer/MIPS 24um, I have compiled a large sample of radio and mid-infrared detected galaxies from the Observations of Redshift Evolution in Large Scale Environments (ORELSE) survey, a survey aimed at systematically searching for large-scale structures in the redshift range of 0.6 < z < 1.3. By virtue of multi-wavelength imaging and high quality spectroscopy, as well as a wide dynamic range of environments sampled by this survey, I classified radio-IR galaxies to three types: galaxies that host either high or low AGN fraction (high-/low-fAGN), and star forming galaxies with little to no AGN activity (SFGs). In this talk, I will focus on the two AGN sub-samples, and particularly, the co-evolution scenario of AGN and SF in these galaxies. Across the co-evolution scenario, their environmental preference remains, which suggests that galaxies might be in an orbital motion around the cluster/group during the scenario. Finally, I will describe a toy model that is designed to demonstrate this co-evolution scenario.
Co-Authors: Brian C. Lemaux, Lori M. Lubin, John McKean, Neal A. Miller, Debora Pelliccia, Christopher D. Fassnacht, Adam Tomczak, Po-Feng Wu, Dale Kocevski, Roy Gal, Denise Hung, Gordon Squires
Star formation in nearby galaxies
By: Yong Shi
Abstract: Formation of stars in cold gas has played a key role in driving galaxy formation and evolution. Understanding of star formation has gained important progresses from studies of nearby galaxies, thanks to the multi-wavelength observations with high spatial resolutions. It has been found that the processes of star formation should depend on galaxy local environments such as gas mass, stellar mass, metallicity etc. but also show some uniformity over different galactic environments. I will present some recent works in star formation of nearby galaxies and discuss some future progresses that may benefit from synergies between the TMT and other large facilities in the TMT era.
Atmospheric structures of brown dwarf revealed with TMT
By: Satoko Sorahana
Abstract: My scientific goal is to comprehensively understand the atmospheres of stars, brown dwarfs, and exoplanets. In order to accomplish this goal, I attempt to study atmospheres of brown dwarfs and exoplanets, which are missing-links between stars and planets in our solar system. My scientific goal using TMT is to gain a further understanding of their atmospheres, which is still unknown. Since isolated brown dwarfs are observed easier than exoplanets orbiting around their central star, the studies of brown dwarfs can precede those of exoplanets. However, many questions about brown dwarf atmosphere remain unanswered yet. I have been studying their atmospheres by comparing between near-infrared spectra taken by direct observations and theoretical predictions. We now know that there are deviations between observational and theoretical spectra. This indicates that the current atmospheric model, which applies the radiative equilibrium, has still not reproduced the atmospheres of brown dwarfs, and it is found that the non-equilibrium processes should be considered for the brown dwarf atmosphere. We should now investigate the three-dimensional structure of atmosphere taking non-equilibrium atmosphere into account, and TMT will give us the detailed vertical temperature structure in brown dwarf atmosphere.
ExoWorlds: Exploring future avenues for exoplanet characterization
By: Anandmayee Tej
Abstract: With over four thousand exoplanets now detected, the field of exoplanetary science is revolutionzing modern astronomy. Exoplanets are now known orbiting other stars with astounding diversity, ranging from hot Jupiter-sized planets to small rocky planets in the habitable zones. Presently, the major focus in the field is to study in detail the planetary atmospheres and shed light on the involved atmospheric processes and chemical compositions, which in turn can give significant insight in areas of planet formation and planetary interiors, apart from having crucial astrobiological implications. In this talk, I will give a brief overview of the proposed ExoWorlds mission and discuss the various critical aspects required for the design and development of future facilities for high-precision spectroscopic characterization of exoplanets. With TMT slated to be operational in the mid-2020s, complementarity between the science goals of ExoWorlds and the Exoplanet chapter of TMT will also be discussed to initiate collaborative efforts to maximize the science.
The Synergy between Giants - FAST and TMT
By: Chao-Wei Tsai
Abstract: The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project. Upon its completion in September of 2016, FAST is the largest single-dish radio facility in the world and can surpass the 300-meter Arecibo and the 100-meter GBT in terms of absolute sensitivity in the 70 MHz to 3 GHz bands. While under commissioning, FAST has discovered about a hundred of new pulsars including the first MSP, which has been confirmed by the Fermi team. Since late April of 2019, FAST has started science operation for the shared-risk program while continuing the commissioning effort. In this talk, I will give a brief introduction of the FAST, discuss its current status and the aspiration of the early sciences programs. I will also mention a few research directions that can utilize both FAST and TMT in the era of parallel operations of both giant telescopes.
Development Progress of Dichroic mirror for TMT WFOS
By: Jianguo Wang
Abstract: The Wide Field Optical Spectrograph (WFOS) is the seeing-limited, wide-field multi-object optical imaging spectrograph planned for first-light operation on the Thirty Meter Telescope (TMT). The current WFOS optical designs, including both slicer-WFOS and fiber WFOS, provide two or more color channels, spanning in the 310nm~1000nm wavelength range. Dichoric mirrors are key component to separate incident light into several channels. An efficient design algorithm for dichroic mirror will be presented in this paper, where a merit function composed of reflectivity, transmittance and cross band between neighbored channels has been constructed. The designed mirror showed good tolerance for angle, thickness and refractive index error, which can be fabricated by electron beam evaporation with ion-beam assisted deposition. The experimental spectral performance shows the average reflectance was larger than 98% between 310nm and 550nm and the transmittance (single side, mean-polarization) was larger than 97% between 570nm and 1000nm with the angle of incidence 28±5°. Environmental durability tests, such as low temperature, high-low temperature shock and constant temperature and humidity, are also evaluated according to the ISO 9022-2:2002.
Co-Authors: Shijie Liu, Hongbo He*, Chaoyang Wei, Jianda Shao Corresponding author: hbhe@siom.ac.cn
TMT Synergy with Spacecraft Exploration of Outer Planet Systems
By: Michael H Wong
Abstract: Ground-based observations complement spacecraft exploration missions in multiple ways. Imaging from the ground (and Hubble) supports missions like Juno and the Galileo Probe, while high-resolution spectroscopy compensates for limitations in missions like Cassini.
In the TMT era, we anticipate that the outer solar system will be explored by the ESA JUICE mission, as well as NASA's Dragonfly mission to Titan, Europa Clipper mission to the Jupiter system, and a flagship mission to Uranus and/or Neptune. Additional missions may also be launched by the growing community of spacefaring nations and consortia.
Several capabilities of TMT will be essential for successful synergy with spacecraft missions. Queue scheduling will enable brief observations to satisfy temporal constraints of solar system observations, especially since targets are bright and do not require long integrations. High-dispersion spectroscopy is difficult to accommodate in spacecraft payloads, so TMT's spectroscopic capabilities provide a natural synergy with these missions. For imaging, TMT’s diffraction limit will enable spatial resolutions comparable to spacecraft capabilities in some cases. Cadence observations (perhaps supplemented or triggered by smaller-telescope and amateur observations) can build up a timeline of activity to assist with spacecraft observation planning and provide both spatial and temporal context for in situ measurements.
Co-Authors: Michael H. Wong (UC Berkeley, mikewong@astro.berkeley.edu) Caitlin A. Griffith (Univ. Arizona)
High energy space missions at IHEP
By: Shaolin Xiong
Abstract: In this talk, I'll briefly introduce a fleet of high energy astrophysics space missions that are led by IHEP or in which IHEP played an important role. In the order of the scheduled or expected launch date (in parentheses), they are GECAM (2020), SVOM (2021), EP (2022), POLAR-2 (2024), HERD (2025), eXTP (2027) and CATCH (2030). Since eXTP and CATCH are quite likely to operate in the TMT era, thus I'll emphasize the potential synergetic science programs between these missions and TMT. On the other hand, synergy observations with TMT could also provide inputs to the design of eXTP and CATCH.
Co-Authors: Shuang-Nan Zhang, Lian Tao
An Overview of the Chinese Space Station Telescope
By: Hu Zhan
Abstract: The Chinese Space Station Telescope is a major science project of China Manned Space Program. It is a serviceable 2m off-axis telescope to be launched in the same orbit as the Chinese space station. The first-generation instruments include a survey camera, a terahertz receiver, a multichannel imager, an integral field spectrograph, and a cool-planet imaging coronagraph. About 70% of the orbital time of the first 10 years will be devoted to survey operations using the survey camera. Roughly 17,500 square degrees of the sky will be observed at a resolution of 0.15" in at least 6 broadband filters from 250nm to 1000nm, reaching an average depth of AB 25.5 mag (point source, 5-sigma). Low resolution slitless spectra will be taken at the same time over the same area reaching a broadband equivalent depth of AB 22-23 mag. Deeper exposures will be made in selected areas. The other four instruments will carry out both pre-defined key projects and guest observer program. In this talk, I will give a brief introduction to the project and discuss synergies with the TMT.
Co-Authors: Hu Zhan (National Astronomical Observatories of China) and the CSST Team
Cosmological implications of large galaxy surveys
By: Gongbo Zhao
Abstract: Large galaxy surveys is one of the robust probes of cosmology via Baryonic Acoustic Oscillations (BAO) and Redshift Space Distortions (RSD). In this talk, I will briefly review the recent progress in cosmology using galaxy surveys, and in particular, I will present a new method for the measurement of RSD by combining the pre- and post-reconstructed galaxy samples. I will also discuss the complementarity of cosmological tests between TMT and galaxy surveys including DESI and PFS.
The Multi Channel Imager of the Chinese Space Station Telescope
By: Zhenya Zheng
Abstract: The Multi Channel Imager (MCI) will be one of the 5 orignial instruments aboard the Chinese Space Station Telescope (CSST). MCI is a three-channel imager currently under development by Shanghai Astronomical Observatory and Shanghai Institute of Technical Physics. It covers the wavelength range of 0.255 to 1 micron at the HST-like spatial resolution in a 7'x7' field of view. In this talk, I will briefly introduce the design, the development, and the main scientific goals of MCI, and discuss the synergy between MCI and TMT.
Disentangling galaxy formation history through a population orbit-superposition model with VLT/MUSE data
By: Ling Zhu
Abstract: Stellar motions speak the formation history of a galaxy, in the sense that stars on highly rotating orbits form in-situ from gaseous disk, while stars on radially random-motion dominated orbits are related to violent dynamical processes, like mergers. Combination of stellar kinematics and chemistry allow us to physically identify galactic structures and probe their formation history. This kind of analysis is successful, but was only possible, to Milky Way in which the stellar orbits and chemistry of single stars are resolved with Gaia + spectroscopy. With a newly developed population orbit-superposition method, we are able to uncover the stellar orbit distribution, with orbits tagged with age and metallicity by fitting to IFU data of external galaxies. We demonstrate the power of the method by applying it to a S0 galaxy, FCC 167 observed by MUSE/VLT. Based on the model, we identify an old, metal-rich, concentrated bulge; an old, but metal-poor inner halo consistent to be accreted; and a young, metal-rich disk which itself still shows an inside-out growth. This method could be applied to data from TMT IFU facilities and we can push this analysis to even galaxies beyond local universe.
