Draft (Jan. 18, 2010) Executive Summary

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4TMT science

The powerful combination of the light gathering power and diffraction-limited adaptive optics of TMT will probe the universe in unknown regimes, from extrasolar planets to the largest-scale structure of the universe. The collecting area of TMT will be larger than the current generation of telescope by a factor of 10, and the resolution will be 12 times sharper than what is achieved by the Hubble Space Telescope. Depending on the observation, TMT will see further and see more clearly than previous telescopes by a factor of 10 to 100.

TMT will provide new observational opportunities in essentially every field of astronomy and astrophysics. Because of the decades-long lifetime of TMT and the often-rapid advancement of astronomy into new areas, in this science case we only broadly outline the key science drivers that can be envisioned today. China already has many active research groups in these areas, and joining the TMT will allow these groups to gather first-hand, state-of-the-art observational data and thus enhance their research activities substantially.

  • We emphasize that, as a general-purpose telescope, the legacy of TMT may be on the unknowns, in areas not yet anticipated. It is useful to recall that the major discoveries of HST and the Sloan Digital Sky Survey were not originally outlined in their science proposals.

  • TMT will explore formation processes and the physical properties of extra-solar planets. The discovery of more than 400 extrasolar planets using a variety of methods (radial velocity, transits, and microlensing) reveals that our solar system may be an exception rather than the norm. TMT will allow us to make fundamental discoveries in this area. Radial velocity methods can be pushed into the discovery of terrestrial-planets and planets around types of fainter stars other than the Sun; TMT can also be used to study the kinematics of proto-planetary disks, and enable spectroscopic detection and analysis of extra-solar planet atmospheres through absorption and the direct imaging of extra-solar planets in reflected and emitted light.

  • TMT will provide important constraints on the properties of dark matter and dark energy, and whether fundamental constants of nature changes as a function of cosmic time. The properties of dark matter will be probed with a variety of methods such as gravitational lensing, kinematics of dwarf galaxies, and small-scale structures of Lyman-alpha clouds, while the dark energy can be studied using Lyman-alpha clouds and deep surveys of high-redshift supernovae.

  • TMT will allow investigations of massive black holes throughout cosmic time. TMT can probe central massive black holes to greater distances and to smaller black holes. It will, for the first time, gather a large statistical sample of black holes to study how they correlate with galaxy masses, kinematics, morphologies, and how they evolve out to redshift ~0.4 and, when combined with other methods, beyond. TMT can also study the central black hole in the Milky Way in more fundamental ways using many more stars, with the possibility of measuring general relativistic effects for stars on highly eccentric orbits.

  • TMT will make important contributions to the detection of first light, an outstanding question in astrophysics. The Universe entered a period of “dark ages” when it re-combined at redshift z ~1000 at an age of about 300,000 years old. The “dark ages” were ended when the first light sources turned on. TMT, in synergy of the James Webb Space Telescope (JWST, to be launched in 2014 with a 5-10 year lifetime), will provide spectroscopic observations of the first lighthouses, providing detailed information about the physical properties of these objects, and also their chemical enrichments.

  • The tremendous light gathering power of TMT will allow galaxies, rather than just quasars, to act as background sources to probe the structure along the line of sight. The much higher source densities can be used to perform 3D tomography of the matter distribution from the large-scale structures to small scales. Such studies will also probe the nature of dark matter, dark energy, the constancy of physical constants and chemical enrichment and feedback processes via structure formation.

  • TMT will probe how structures form on different scales in the universe, ranging from planets (as discussed above), stars and galaxies. It will address how galaxies form and evolve as a function of environment and feedback processes from star formation and active galactic nuclei.

The potential science areas to which TMT can contribute are remarkably diverse. This document builds on the science case science cases from the three extremely large telescopes2; we further develop the cases with special emphases on the Chinese astronomical community. The document is divided into a number of related research themes. Each theme follows roughly the format

  • What are the key science questions in the next two decades?

  • Overview of current research activities.

  • Detailed discussion of key science areas. Why is TMT essential for the research?

  • Strengths and weakness of Chinese astronomy in the theme:

  1. Existing research teams within China.

  2. Identify areas that need to be strengthened in order to improve the competitiveness of China in terms of student training, and team building.

  • Possible TMT observational programs:

  1. Complementarities with other Chinese projects: SVOM, FAST, DOME-A, HXMT?

  2. What can be done in the immediate term using 8-10m class telescopes?

4.1Search for and Characterization of Extrasolar Planets

Jilin Zhou (Nanjing), Doug Lin (KIAA/Santa Cruz), Jian Ge (Florida), Liang Wang (NAOC), Yujuan Liu (NAOC), Gang Zhao (NAOC)
Key questions:

  1. What types of planets exist around other stars?

  2. How did Earths and other planets form and evolve?

  3. What fates await planetary systems?

  4. Is there any sign of life on planets other than the Earth?

  5. How did life emerge and proliferate?

Planetary detection and characterization are the most rapidly advancing branches of

astronomy and astrophysics. Space exploration has unveiled that worlds of our solar system come in a tremendous variety. Even they hardly prepared us for the sheer diversity of extra solar planets. Barely a decade ago those who study how planets form had to base their theory on a single example—our solar system. Now they have dozens of mature systems and dozens more in birth throes. No two are alike. The basic idea behind the leading theory of planetary formation—tiny grains stick together and swoop up gas—conceals many levels of intricacy. A chaotic interplay among competing astronomical, geologic, chemical, and biological processes leads to a huge diversity of outcomes.

Time has arrived for the emergence of a new discipline, astrobiology, which confronts the fundamental age-old conundrum ``are we alone in this universe?’’ A logical and systematic approach to estimate the population of extra terrestrial intelligence is to quantitatively determine each entry in the Drake equation. The advent of TMT will bring to reality the long-soughtafter census on 1) the fraction of nearby stars with planets, 2) the fraction of these planets which are potentially habitable, and 3) the fraction of these supporting platforms show any signs of past or ongoing biological activities. The outcome of these surveys will provide scientific confirmation or quantitative constraints on conceptual conjectures and philosophical speculations on the origin and proliferation of life.

Along the paths of these discoveries, we will be able to extract information on 1) the sequence of planetary assemblage, 2) the dominant mechanisms that led to their diversity, and 3) the selection processes that channelled their destiny. Some of these issues are also relevant, albeit on different special and time scales, in the context of star formation, galaxy evolution, and active galactic nuclei. We list below some important technological advancement anticipated in the search and characterization of extra solar planets that will be brought about by TMT.

4.1.1Radial velocity detections of near planets

Key questions:

  1. What are the mass, size, and semi major axis distributions of planets around nearby stars?

  2. Did planets acquire their structural and kinematic diversity at birth or during the main sequence life span of their host stars? How did these properties evolve as their host stars age?

  3. How do frequencies, masses, and orbits of planets depend on the mass, metallicity, age, binarity, and Galactic environment of their host stars?

  4. How does extra architecture of multiple planetary systems around nearby stars compare with that of the Solar System?

  5. What fraction of nearby stars bear earth-like planets in habitable zones

A vast majority of the known extrasolar planets were discovered indirectly by measuring the reflex motions of their parent stars through radial velocity (RV) measurements[i]. Most of these planets are Jovians orbiting G and K dwarf stars where the planet/star mass ratio was large enough to produce measurable reflex motions. TMT with HROS will expand the number of host stars accessible to Doppler spectroscopy by a factor of 30 by allowing a greater volume of space to be explored[ii]. In addition, the higher sensitivity will allow lower-mass stars, such as M stars – the most common stars in the galaxy, to be observed. These stars are more strongly affected by gravitational perturbations so lower-mass planets can be detected. In fact, TMT will be able to detect Earth-mass planets orbiting in the habitable zone of M stars (the habitable zone is the region surrounding the star where a planet would have a temperature conducive to the formation of life).
Main science areas:
1. Detection of More Planets around Different Type of Stars

Over the next 15 years, a major goal will be to extend these RV surveys to M and L dwarf stars for several reasons. First, many more M and L stars exist than G and K stars – it is likely that the majority of planets in the local solar neighborhood revolve around such stars. Second, since M and L stars have lower mass, rocky, Earth-like planets can produce measurable reflex motions. Third, planets revolving in M and L dwarf habitable zones will have periods of 30 – 100 days or less, making it straightforward to characterize such orbits in less than a year.

The intrinsically more efficient HROS design coupled with the 10-fold increase in TMT collecting area relative to Keck will enable the required RV precision at V=11, 12, and 13 in approximately 1.5, 3.5, and 8.5 minutes, respectively. These shorter exposure times allow for the characterization of an entire orbital period (30 – 100 days) for tens to hundreds of candidate planets around early M dwarf stars in one year. Only the vagaries of time allocation limit the potential sample size.
2. Characterization of multiple-planet systems

The probability of finding additional planets around solar type stars with known gas giants is much higher than that of finding the first gas giants. This tendency may either signify that the formation of gas giants is prolific above a threshold condition or it can promote the production of second-generation planets. Gravitational perturbation among multiple planets also induces secular evolution and dynamical instabilities lead to the excitation of planets’ eccentricity, inclination, and their orbital migration. The dynamical ``porosity’’ of multiple planetary systems provides important clues and constraints to theories of planet formation and celestial mechanics.

The most straightforward approach is to conduct follow-up radial velocity surveys of stars with known planets. Planets’ mass distribution within multiple systems will show whether rocky planets and gas giants are specially ordered and segregated around other stars as in the solar system. Such results will have profound implications on sustainability of habitable planets.

3. Origin of dynamical diversity

With a much larger sample, we can determine the fraction of multiple systems are in well separated circular orbits (similar to the solar system), mean motion resonances (similar to the Galilean moons), or highly eccentric orbits. It is possible that the preservation of systems with orderly orbits (like the solar system) requires planets with modest mass and long periods that can eventually be detected by second-generation instruments on the TMT.

Radial velocity measurement of transiting planets (see below) will provide informative statistics on the inclination between the axes of stellar spin and planets’ orbits. Highly inclined planetary orbits suggest that some planets may be strongly scattered whereas spin alignment is indicative of gentle and gradual dynamical evolution. Follow-up observation of stars with directly imaged long-period gas giant planets can also place constraints on whether these planets formed through gravitational instability or through core accretion.

4. Evolution of planetary systems around relatively young stars

Dynamical evolution of planets’ orbits proceeds rapidly around relatively young stars. Due to changes in the gravitational potential, the depletion of gaseous and debris can lead to both eccentricity excitation and orbital migration as well as frequent giant impacts. In addition, young stars reside in crowded neighborhoods where perturbations of their neighbors are likely to destabilize their orbits. For planets in the proximity of their host stars, intense tidal interaction may also lead to infant mortality.

With TMT’s NIRES, it is possible to carry out radial velocity surveys around young stars. Direct comparison with planetary census around mature stars will provide clues on the evolution of planetary systems.

5. Detections of Earth mass Planets in Habitable Zones

Detecting rocky, Earth-like planets in the habitable zones of cool dwarf stars requires radial velocity measurements with 1 m/s precision. The California-Carnegie Planet Finder team (PIs: Butler, Fisher, Marcy, Vogt) has demonstrated that such precision is possible on Keck/HIRES using an iodine cell near 0.5μm. However, to reach interesting apparent flux limits for M stars would require 1 – 3 hours per RV measurement with Keck, severely constraining the number of stars that can be surveyed. Given the diversity of planetary systems discovered so far, it is clearly necessary to survey tens or hundreds of stars, not just a handful, to truly characterize the potential population of nearby rocky planets.

6. Followup observations of extrasolar planets discovered by Kepler and CoRoT

RV survey results alone contain ambiguities about inclination angles and hence planetary masses. It may be possible to remove such ambiguity in systems with multiple stars using high spatial resolution, precision astrometric observations with TMT/IRIS (see, e.g. Neuhäuser et al. 2006). Transit surveys like Kepler and Corot have a different challenge. They may detect dozens to hundreds of nearby rocky planet candidates with known inclinations. But followup RV measurements will be necessary to constrain the masses of these candidates and separate “false positive” icy planets on long orbits from rocky planets on short orbits. At V = 14, TMT/HROS can reach 1 m/s in less than 30 minutes per point. Hence, HROS (and perhaps NIRES) will be ideal instruments for Kepler and Corot follow up investigations.

Possible TMT programs:

  1. A systematic and thorough surface of extrasolar planets around solar neighbourhood, so that it may give the host rate of planets with different types of stars, the distribution of masses, semi-major axes, eccentricities and possibly inclinations of these planets; the relationship between planet-host stars with their abundance of metallicities, etc.

  2. A search of habitable planets in solar neighbourhood. Once they are found, try to characterize their orbital and physical signature.

  3. Followup observations of transit extrasolar planets discovered by Kepler and CoRoT.


  1. http://extrasolar planet.eu

  2. http://www.tmt.org (and hereafter through the following 3 Sections)

4.1.2Direct imaging of extrasolar planets

Key questions:

  1. How can we receive the photons form a planet around a bright star?

  2. Are planets in distance orbits or in brawn dwarf system common in planetary systems?

  3. What can we infer from the planet image?


It is now possible, using adaptive optics, to directly image giant planets. The higher resolution provided by TMT/PFI will extend the reach of these observations to the nearest star-forming regions, making it possible to relate the properties of the planetary systems to the environment, and to observe directly large planets forming within circumstellar disks. TMT will also be able to detect planets that are close to their host star, probing for the first time scales that are comparable to the size of the inner Solar System. Since planets in this region intercept and reflect more light from the host star, it will be possible to image even cold Jovian planets directly by reflected starlight and study the atmospheric composition of these planets. Via direct imaging, TMT will be able to explore a regime not addressed by RV surveys.

Main science areas:

  1. Imaging Young Giant Planets in Distance Orbits

Where Giant plant in far distance (>50AU) formed through gravitational instability or core accretion model is still in controversial. For example, three planets of around 10 Jupiter-masses are imaged in HR 8799 system in 2008 [1]. More samples of planets in distance orbits are very useful to understand their formation scenario.

Using a combination of coronographic imaging and precision astrometry, TMT/IRIS can explore the moderate-contrast (103 – 105) wide-separation (> 50 AU) regime that may be occupied by young (< 1 Gyr), self-luminous Jovian planets. If such planets are detected, moderate-resolution spectroscopic follow up will also be possible with IRIS.

  1. Imaging evolved giant planets in mid-distance orbits

The detection of giant planets in closer orbits (~10AU) would be very helpful, compliment to the radial velocity, which favours the planets in close-in orbits, and also to micro lensing technique, in which the stars are mostly far away and the experiments are not repeatable. The increasing of planets samples in mid-distance orbits will, of course, helpful to understand questions, such as whether the Solar system is special among planetary systems.

To study more evolved planets closer to their parent stars, higher contrast imaging is necessary. TMT/PFI is designed to enable 3 λ/D spatial resolution, high-contrast (108) imaging with low spectral resolution (R ~ 70) followup at 1.65 μm. A moderate-resolution spectroscopic mode (R ~ 700) will also be available. This will allow systematic surveys in the mass range 0.5 < MJ < 12 over 0.5 – 50 AU out to 100 pc or more.

  1. Imaging giant planets around brown dwarfs

Planet around brown dwarf stars are relative easier to be imaged, since the brightness contrast between the star and the planets are much easier. The first planet being imaged is mass with four times of Jupiter orbiting a brown dwarf  2M1207 [2]. Planet Formation in brown dwarf system is not known much by us. To have more planet samples in brown dwarf stars are helpful to the study of planet formation in these systems.
Possible TMT programs:

  1. A systematic image of planets in distance orbits so that a statistics may be available. By fitting their internal structures, we may distinct whether they are formed through gravitational instability or core-accretion scenario.

  2. Search for more giant planets in moderate distance to the host star. Try to find planetary systems similar to the Solar system.

  3. Detect more planets around brown dwarf stars. Develop the theory of planet formation around brown dwarf stars.


  1. Marois, C. et al. 2008, Science 322:1348

  2. Chauvin G. et al. 2004, Astron. & Astrophys.  425 , L29

4.1.3Planetary atmospheres from absorption line studies

Key questions:

  1. What is the difference between the atmospheres of extrasolar planets and Earth?

  2. Is there any bio-maker in other rocket planets?


The light received from distant planetary systems is a combination of light from the planets and that from the host star. At optical wavelengths, the star is typically about a billion times brighter than the planets, so the light from the planets cannot be distinguished. However, at mid-infrared wavelengths, the brightness contrast between a planet and its host star is much smaller, making it possible to distinguish spectral features in the radiation emitted by the planet, superimposed up on the spectrum of the star. These features have a small wavelength shift due to the motion of the planet around the star, which makes it possible to separate them from features produced by the star itself by a process of spectral deconvolution.

For planets that pass in front of their host star, as seen from the Earth, another technique is possible. During the transit, a small portion of the light emitted by the star passes through the atmosphere of the planet. As a result, absorption features due to molecules in the planetary atmosphere are superimposed on the spectrum of the star. These features are extremely weak since only a very small portion of the light is affected by the atmosphere. However, they can be detected with a thirty-meter telescope and high-resolution spectrometer. Simulations indicate that it should be possible to detect oxygen in the atmosphere of an Earth-like planet orbiting in the habitable zone of an M star, in about three hours with TMT/HROS. Detection of oxygen would be highly significant since it is indicative of photosynthesis, and thus the presence of life.
Main science areas:

1. Water, Carbon Monoxide and Methane observation

Between 1 and 2.5 μm, strong water, carbon monoxide and methane features exist and should be observable by TMT/NIRES. Since these features contain 10s to 100s of individual lines, the effective SNR increases by an order of magnitude relative to the measurement of a single line like Na D in the optical. Fast rotating, late M dwarfs are particularly interesting targets in this regard since the amplitude of the Rositter-Mclaughin effect is directly proportional to the stellar rotational velocity.

In the mid-IR (5 – 20 μm), such observations become easier for Jovian planets because the contrast between the planetary and stellar spectral features is higher (103 – 104 ; see, e.g., [1,2]) and the molecular features found in the planetary atmospheres are more distinctive. Richardson et al. (2007) have published the first such mid-IR measurement based on Spitzer observations [3].

  1. Search for Oxygen

The most exciting but perhaps more speculative high-resolution spectroscopic project is the search for oxygen (a key bio-marker) in the atmospheres of rocky planets transiting M dwarf stars. Simulations by Webb & Wormleaton [4] suggest such measurements are possible if R ~ 40, 000 spectra with SNR ~30,000 can be achieved for V = 13 M dwarf stars – well within the grasp of TMT/HROS. More than 2500 candidate stars are visible from any given location on Earth. The obvious approach is to narrow down this list using an RV survey and then focus on the most suitable candidates. Of course, before investing this effort, the simulations of Webb and Wormleaton must be confirmed and extended.

Possible TMT programs:

  1. Detection of water, carbon monoxide and methane features in selected Jovian planets.

  2. Search for Oxygen and other bio-maker in the atmosphere of rocky planets during the transiting of M dwarf stars.


  1. Sudarsky, D., Burrows, A. & Hubeny, I. 2003, ApJ, 588, 1121

  2. Burrows, A., Surdarsky, D. & Hubeny, I. 2004, ApJ, 609, 407

  3. Richardson, L.J. et al. 2007, Nature, 445, 892

  4. Webb, J.K. & Wormleaton, I. 2001, PASA, 18, 252

4.1.4Protoplanetary disks

Key questions:

1. Why do some planetary systems contain hot Jovian planets close to their parent star while at least one (the Solar System) has rocky planets in the same region?

2. Are planets formed mostly by gravitational instability or by core-accretion scenario?

3. How and when protoplanet and planet orbits are circularized?

4. Are there any pre-biotic molecules in disks?

Protoplanetary disks are flattened rotating disks of gas and dust surrounding newly formed stars. The inner (r < 10 AU) regions of proto-planetary disks are particularly interesting since these are the regions where most planets may form. Such inner disks are typically too distant to be spatially resolved by TMT. However, the Keplerian rotation of disks can be used to separate disk regions in velocity (and hence radius) and derive the radial variation of line intensity by fitting resolved line profiles. Making such separations in velocity demands high-resolution spectroscopy. Given the expected temperatures of these disks, atomic and molecular lines of interest will lie between 1 and 25 μm.

Of particular interest to astrobiology are organic molecules, the building blocks for pre-biotic molecules such as amino acids, nucleobases, and sugar-related compounds, which have transitions in this wavelength regime. High-resolution spectroscopy also provides data on two key parameters: gas dissipation time scale (and how it relates to dust dissipation time scale measured by, e.g. Spitzer) and gas viscosity. Knowledge of both parameters is important to understanding how and when protoplanet and planet orbits are circularized – a key issue in planet formation theory. Yet, both parameters are currently poorly constrained by observation.
Main science areas:
1. Probing gas dissipation timescales

The timescale for dissipation of gas in circumstellar disks governs the viability of plausible giant planet formation mechanisms and consequently, the range of plausible giant and terrestrial planet architectures. Moreover, the persistence of gas in the terrestrial planet region of the disk also affects the masses, eccentricities and consequently the habitability of terrestrial planets. The observation of disk dissipation timescale is useful to tell the two basic regimes of planet formation: gravitational instabilities vs. core accretion mechanisms. If the timescale for gas survival is short (t << 10 Mir) at distances beyond several AU in most systems, gas giant formation via accretion onto a rocky core is unlikely. Moreover, if the residual gas in the terrestrial zone is << 10-3 that of a minimum mass solar nebula, it becomes difficult to understand how the Earth and its sister planets in the inner solar system ended up in low-eccentricity orbits. TMT/MIRES will have the flux sensitivity and spatial resolution needed to constrain this timescale across a wide variety of environments using both molecular (e.g. H2) and atomic tracers.

2. Probing protoplanetary disk gaps
Forming extrasolar giant planets should produce tidal ‘gaps’ in the accretion disk. Optically thin emitting gas in these gaps can be used to diagnose the presence of forming protoplanets and quantify their orbital distances and masses. Making such measurements can provide insight into the formation mechanism for giant planets, and via comparison with the architectures of mature planetary systems, their dynamical evolution. Determining the Keplerian velocity of emitting gas within the gap provides a measure of the planet semimajor axis, while their mass can in principle be assessed from the gap width as inferred from the shape of the emission line arising from the gas diagnostic. The targets are young stellar objects still surrounded by circumstellar accretion disks – diagnosed via their infrared spectral energy distributions (large excess emission from dust embedded within the disk) and from optical photometry (UV excess) and spectroscopy (line profiles indicative of accretion along magnetospheric columns). A variety of gas diagnostics sensitive to emission arising at different temperatures (300 K at 1 AU; 150 K at 5 AU) will be used; they include CO fundamental (4.6μm), H2 (12μm; 17μm).

  1. Pre-biotic molecules in disks

A large number of extra-terrestrial organic and pre-biotic molecules are known to exist both in the Solar system and the interstellar medium, and a better understanding of the inventory and formation of these molecules in star-forming molecular clouds and circumstellar disks is a key goal of astrobiology. The extent to which interstellar organic material is destroyed or modified as it is accreted into and processed within protoplanetary disks is an open question. While the similar compositions of cometary volatiles and interstellar molecules strongly suggest a direct connection, numerous differences indicate processing within the presolar nebula. In addition, complex organic compounds could be synthesized in regions of protoplanetary disks by the similar processes that operate in the interstellar medium.

Mid-infrared spectroscopy with MIRES will be an essential tool for investigating the inventory and content of organic molecules in protoplanetary disks. Most simple and complex hydrocarbon compounds have strong mid-infrared transitions and a majority of these are accessible to ground-based observations. High spectral resolution is essential, particularly in searching for more rare molecular species. A given spectral region may be crowded with molecular lines, and lines of more complex molecules will be weak due to lower abundances and the typically larger number of transitions. Thus, the very high signal-to-noise observations obtainable only with TMT are required. Broad wavelength coverage, providing access to large numbers of transitions, will also increase the detectability of rare molecules.

Possible TMT programs:

  1. Probing gas dissipation timescales by systematically observe the presence of disk at variation of young stellar objects, and estimate;

  2. Probing inner disk holes of disk, connecting the observation with RV detection of extrasolar planets.

  3. Detection of pre-bio molecules in disks. Compare them with the organic molecules in our solar system.

China’s strengths and weakness in extrasolar planet research:

Extrasolar planet research is one of the most exciting topics in astrophysical research, with major breakthroughs in the last decade. World-leading theoretical studies of planetary systems, their formation and dynamics are being actively pursued at KIAA (PKU) and NJU. Observationally, this area is still under-developed in China involving only two groups nationally. A group at NAOC is surveying young stars with the 2.16 m telescope at the Xinlong station, under a pan-Asia joint project with Japan and Korea. So far one extrasolar planet has been found by the NAOC group3. Yunnan Astronomical Observaory (YNAO) will also begin RV detection of planets with the 2.4m telescope in Lijiang through an international collaboration between University of Florida, and University of Science and Technology of China (USTC), and Nanjing University (NJU). These observational searches can be significantly enhanced by joint activities with institutes heavily involved in TMT (such as UC Santa Cruz, Berkeley and Caltech), through concrete research projects and joint student training.

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