3rd DTA Symposium
The Origins of Planetary Systems:
from the Current View to New Horizons

Abstract Booklet

June 1 - June 4, 2015, NAOJ, Tokyo3rd DTA Symposium

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Scientific Rationale:Ever since the first discovery of an extrasolar planet orbiting around a Sun-like star in 1995, morethan 1900 exoplanets (+ about 4000 candidates) have been observed so far. A number of ongoing andfuture surveys do and will keep increasing the population of observed exoplanets. In addition, the adventof ALMA with significantly upgraded capabilities has recently enabled the unprecedented high resolution
observations at (sub)mm wavelengths. For instance, the long-baseline science verification campaign
reveals multiple gaps in a circumstellar disk around HL Tau, a young (< Myrs) YSO, which may be asignature of planet formation. These revolutionary observations are currently triggering the rapid progresson the understanding of the formation and evolution of planets, which may occasionally require paradigm
shifts. It is fascinating that planet formation can serve as a fundamental platform to unite theseobservations and related sciences.

Aims and Scopes:
In a golden era of planetary sciences, it would be of essential importance to(1) examine both theoretically and observationally the current understanding of how planetary systems
are born out of their natal circumstellar disks and of how the systems evolve with time,(2) summarize unresolved issues and open questions, and(3) attempt to develop new ideas/visions to derive a better understanding of planet formation.
This workshop will be designed to cover the above points.
Specifically, this workshop will stimulate the following activities;- review the current status of both theory and observations- discuss the latest results of both theoretical and observational work
- summarize key questions that will/should be addressed in the near future- trigger new collaborative work among theorists and observers- enhance interactions between theorists and observers- encourage involvement of young people including postdocs and students- provide young students with plenty of chance to interact both with active researchers in the world andwith key scientists in Japan3rd DTA Symposium

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Schedule:
Sunday, May 31,

Day 0: Welcome party at 6pm-

Monday, June 1,

Day 1:

9:00 - 10:00

Registration

10:00-12:15 (135mins)
10:00 - 10:10

Current view of planet formation + HL Tau

Hasegawa, Yasuhiro (NAOJ)(SOC chair)

10:10 - 10:55

Adibekyan, Vardan (Institute of Astrophysics and Space Sciences – CAUP)(review)

10:55 - 11:40(theory of planet formation)

Akiyama, Eiji (NAOJ)(keynote)

12:15 - 13:30

Heavy meteal rules: star-planet connection

Kokubo, Eiichiro (NAOJ)(review)

11:40 - 12:15

Opening remark(ALMA + HL Tau)

Lunch

13:30 - 15:30 (120mins)
13:30 - 14:15

Disk formation in the context of star formation I

Sakai, Nami (RIKEN)(review)

14:15 - 15:00

Li, Zhi-Yun (University of Virginia)(review)

15:00 - 15:20(YSO (disk) observations)(disk formation, initial stage)

Tsukamoto, Yusuke (RIKEN)(contributed)

15:20 - 15:30

Two types of circumstellar disk evolution induced by the Hall term

Poster short talks
Matsumoto, Yuji (NAOJ)
Okada, Kazsushi (the University of Tokyo)
Ono, Tomohiro (Kyoto University)

15:20 - 16:00

Break

16:00 - 17:40 (100mins)
16:00 - 16:45

Disk formation in the context of star formation II

Machida, Masahiro (Kyushu University)(review)

16:45 - 17:05

Disk Formation and Jet Driving in Collapsing Cloud Cores

Kunitomo, Masanobu (Nagoya University)(contributed)

Pre-main sequence evolution of low-mass stars: Effects of planet
formation on stellar composition

17:05 - 17:40

Discussion (discussion leader: Nakamura, Fumitaka)3rd DTA Symposium
Tuesday, June 2,

Day 2:

10:00 - 11:50 (110mins)
10:00 - 10:45

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Protoplanetary disks I

Perez, Laura (NRAO)(review)

10:45 - 11:30

Nomura, Hideko (Tokyo Institute of Technology)(review)

11:30 - 11:50(disk observations)Chemical Processes in Protoplanetary Disks

Aikawa, Yuri (University of Tsukuba)(contributed)

Analytical Formulas of Molecular Ion Abundances and N2H+ Ringin Protoplanetary Disks

11:50 - 12:10

Fujii, Yuri (ELSI)(contributed)

12:10 - 13:30

Non-equilibrium Ionization Degree and MRI in Protoplanetary Disks

Lunch

13:30 - 15:15 (105mins)
13:30 - 14:15

Protoplanetary disks II

Lyra, Wladimir (Caltech/JPL)(review)

14:15 - 14:35(gas dynamics in disks)

Inutsuka, Shu-ichiro (Nagoya University)(contributed)

The Origin and Fate of Rings in HL-Tau: Diversity of Planet
Formation Mechanisms

14:35 - 14:55

Sirono, Sin-iti (Nagoya University)(contributed)

14:55 - 15:15

Collsion simulation of sintered icy aggregates

Mori, Shoji (Tokyo Institute of Technology)(contributed)

Electron Heating and Suppression of Magnetorotational Turbulencein Protoplanetary Disks

15:15

Conference photo

15:15 - 16:00

Break

16:00 - 17:40 (100mins)
16:00 - 16:45

Protoplanetary disks III

Dong, Ruobing (UC Berkeley)(review)

16:45 - 17:05

Observational Signatures of Planets in Protoplanetary Disks

Kanagawa, Kazuhiro (Hokkaido University)(contributed)

Disk-planet interaction and gap formation induced by a giant planet
in protoplanetary disks

17:05 - 17:40

Discussion (discussion leader: Fukagawa, Misato)3rd DTA Symposium

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Wednesday, June 3, Day 3:
10:00 - 11:50 (110mins)
10:00 - 10:35

Exoplanets: observations

Kusakabe, Nobuhiko (NAOJ)(keynote)

10:35 - 11:10

Hirano, Teruyuki (Tokyo Institute of Technology)(keynote)

11:10 - 11:30(SEEDS)(transit)

Omiya, Masashi (NAOJ)(contributed)

11:30 - 11:50

Occurrence rate of giant planets around massive stars

Kamiaka, Shoya (The university of Tokyo)(contributed)

Re-characterization a gravity-darkened and precessing planetarysystem PTFO 8-8695

11:50 - 13:30

Lunch

13:30 - 15:35 (125mins)
13:30 - 13:50

Exoplanets: formation & evolution

Kominami, Junko (Tokyo Institute of Technology)(contributed)

High-resolution, global N-body similaton of planetary formation:
Outward migration of a protoplanet

13:50 - 14:10

Wakita, Shigeru (NAOJ)(contributed)

14:10 - 14:55

Chatterjee, Sourav (Northwestern University)(review)

14:55 - 15:15(planetary dynamics)

Rieder, Steven (RIKEN)(contributed)

15:15 - 15:35

Impact of stellar encounters on planetary systems

Kobayashi, Hiroshi (Nagoya University)(contributed)

15:35 - 16:00

Constraints on planetesimals implying from Itokawa dust particles

Planet Formation and Debris Disks

Break

16:00 - 17:40 (100mins)
16:00-16:45

Basu, Shantanu (University of Western Ontario)(review)

16:45-17:05

GI
(GI)

Takahashi, Sanemichi (Tohoku University)(contributed)

The revised criterion for the self-gravitational fragmentation of
protoplanetary disks

17:05-17:45

Discussion (discussion leader: Ida, Shigeru)

3rd DTA Symposium
Thursday, June 4,

Day 4:

10:00 - 11:55 (115mins)
10:00-10:45

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Planetary atmospheres + Future missions

Lopez, Eric (University of Edinburgh)(review)

10:45-11:20

Fukui, Akihiko (NAOJ)(keynote)

11:20-11:55(atmosphere observations)

Narita, Norio (NAOJ)(keynote)

11:55 - 13:30(exoplanet atmospheres)(K2 + TESS)

Lunch

13:30 - 15:20 (110mins)
13:30-14:05

Future mission + Astrobiology + concluding remark

Sato, Bun'ei (Tokyo Institute of Technology); Omiya, Masashi (NAOJ)(keynote)

14:05-14:50

Tamura, Motohide (NAOJ)(review)

14:50-15:20(IRD)
Exoplanet Researches at the NINS Astrobiology Center (ABC)

Hasegawa, Yasuhiro (NAOJ)(SOC chair)

16:00 - 17:00

4D2U theater

18:00 -

Banquetconcluding remark

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Heavy meteal rules: star-planet connection
Vardan Adibekyan (IA-Porto)
Shortly after the discovery of the first extra-solar planet, many studies showed that stars hosting giant
planets have significant metallicity excess when compared with the stars without known giant planets.
Curiously, this strong metallicity-giant planet correlation is not found for the lowest mass planets. On theother hand studies aimed to clarify whether the planet-hosting stars are different from stars withoutplanets in their content of individual elements (other than iron) yielded contradictory results. I will review
the most recent results by discussing the importance of individual light and heavy elements for theformation and evolution of planets. I will also present the latest results about the role of metallicity on thearchitecture of planets.

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A Standard Scenario for Formation of Planetary Systems
Eiichiro Kokubo (NAOJ)
In the standard scenario for formation of planetary systems, a planetary system forms from a
protoplanetary disk around a star. A protoplanetary disk is a by-product of star formation and consists ofgas and dust. The formation scenario can be divided into three stages: (1) formation of planetesimals fromdust, (2) formation of protoplanets from planetesimals, and (3) formation of planets from protoplanets. In
stage (1), planetesimals form from dust in the protoplanetary disk through coagulation of dust grains or
gravitational instability of a dust layer. Planetesimals are small building blocks of solid planets.
Planetesimals grow by mutual collisions to protoplanets or planetary embryos in stage (2). The final stage(3) depends on a type of planets. The final stage of terrestrial planet formation is giant impacts amongprotoplanets while sweeping residual planetesimals. Large protoplanets (cores) capture a massive gas
envelope by self-gravity to become gas giant planets. In the present talk, I review the basic elementary
processes of planet formation and discuss the unsolved problems.

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ALMA Capabilities and Science Review of HL Tau
Eiji Akiyama (NAOJ)
ALMA has provided an unprecedented level of insight into the structure and evolution of gas anddust in circumstellar disks. Observation with a preliminary ALMA long baseline array, consisting of 23
antennas with baselines between 0.2 and 15 km, has now produced remarkable science outputs. In thistalk, I will review some highlights of ALMA updated capabilities and science result with particularemphasis on the structural features of dust component in protoplanetary disk around HL Tau, one of
selected as science verification source in ALMA long baseline campaign. Finally, I will show the recent
NIR observation of the protoplanetary disk around TW Hya to contrast with the disk structure of HL Tau.

3rd DTA Symposium

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Disk Formation Traced by Chemistry
Nami Sakai (RIKEN)
Understanding formation processes of a rotationally supported disk (Keplerian disk) around a newly
formed protostar is an primary target for star formation studies. Although observations of disk structures
have extensively been carried out for Class 0 and Class I protostars, it is still controversial when and how
the disk structures are formed. Nevertheless, important progresses have been made during these years.
With the ALMA Cycle 0 observation, the centrifugal barrier of the infalling-rotating envelope and theassociated drastic chemical change there have been found in the low-mass Class 0 protostellar source
L1527. CCH, c-C3H2, and CS preferentially exists outward of the centrifugal barrier of 100 AU, while
SO only exists in a ring structure around the centrifugal barrier. Since the centrifugal barrier is caused byfundamental physics, i.e. angular momentum conservation, it should also be seen in other protostars. In
fact, the SO ring is found in L1489IRS (Yen et al. 2014). The current understanding on formation of thecentrifugal barrier and its relation to formation of the Keplerian disk will be discussed in the presentation.

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Theory of Protostellar Disk Fromation
Zhi-Yun Li (University of Virginia)
Disk formation, once thought to be a simple consequence of the conservation of angular momentum
during the hydrodynamic core collapse, is far more subtle in magnetized gas. In this case, the rotation canbe strongly magnetically braked. Indeed, both analytic arguments and numerical simulations have shownthat disk formation is suppressed in strict ideal MHD for the observed level of core magnetization. I will
discuss the physical reason for this so-called "magnetic braking catastrophe," and review possible
resolutions to this problem that have been proposed so far, including non-ideal MHD effects,
misalignment between the magnetic field and rotation axis, and especially turbulence.

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Two types of circumstellar disk evolution induced by the Hall term
Yusuke Tsukamoto (RIKEN)
We show that the Hall term, which is the least studied non-ideal magnetohydrodynamical effect,
significantly affects the formation of circumstellar disks. In our simulations, when the rotation vector andthe magnetic field of the host cloud core were anti-parallel, a large (r  20 AU) and massive disk wasformed almost simultaneously with the protostar formation; however, in the parallel case, only a verysmall disk with a size of r  1 AU was formed. This suggests that the initial size of the circumstellar disk
quantitatively differs depending on the parallel or anti-parallel property of the rotation vector and themagnetic field of the host cloud core. The parallel and anti-parallel property does not changes in time andmay last in subsequent evolution. Recent observations of Class 0 young stellar objects (YSOs) seem tosupport our results. In the large and massive disk, the magnetic flux is largely removed due to themagnetic diffusion, and the magnetic braking becomes unimportant. Alternatively, gravitation instability
plays an important role for the angular momentum transfer in the disk. We also show that an envelopewith a size of r > 100 AU which is anti-rotating against the disk appears in the anti-parallel case, and thisanti-rotating envelope may be observable.

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The eccentricities and inclinations of planets formed through in situ accretion of protoplanets
Yuji Matsumoto (NAOJ)
Most of super-Earths detected by the radial velocity method have significantly smaller eccentricities
than the eccentricities corresponding to velocity dispersion equal to their surface escape velocity (escapeeccentricities). If they are formed through in situ accretion in gas free environment, it is considered thatthe eccentricities of planets are comparable to escape eccentricities by mutual scattering between
protoplanets. However, the eccentricity evolution in the in situ accretion model is not studied in detail.
We have examined the eccentricity of formed super-Earth in the in situ accretion model through N-bodysimulations. At first, we investigated processes of the eccentricity evolution in the in situ accretion modelof protoplanets. We found that the eccentricities of protoplanets increase by mutual scatterings and they
are damped through collisions between protoplanets. In the giant impact stage, protoplanets collide justafter the orbital crossing, and this is when the apocenter of the inner protoplanet is on the pericenter of theouter planet. When protoplanets collide in this configuration, since the random velocities are canceled,the eccentricity of the merged planets is significantly smaller than those of colliding bodies. Orbital
inclinations are also damped by the same mechanism. These damping processes depend on initialeccentricities and inclinations. We also investigated influence of initial random velocities of theeccentricities of formed planet through accretion of protoplanets. When we change initial eccentricities ofprotoplanets, the resultant planets are similar. On the other hand, the initial inclinations changed theformed planets. When we start calculations with more inclined protoplanets, the final numbers of planets
are smaller, and the final angular momentum deficits are larger.

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Subaru/COMICS multicolor mid-infrared imaging of the transitional disk source Oph IRS 48
Kazsushi Okada (the University of Tokyo)
In previous researches, spatially-resolved near-IR, mid-IR and submillimeter observations revealed
the asymmetry in the circumstellar disk of Herbig Ae Star Oph IRS 48. In particular, ALMA 0.44mm
continuum image shows highly localized emission. It is suggested that these structures are caused by one
or more planets in the disk.
In the previous MIR observation with VLT/VISIR, centrally peaked images are obtained in 11.9 µm,
while the 18.7 µm image shows an inclined ring-shaped thermal structure with a gap in the center(Geer+2007).
Here we show new images of Oph IRS 48 at 12.8 µm, 17.7 µm, and 24.5 µm using Subaru/COMICS.
With these multiwavelength data set, we can derive the emitting dust temperature and discuss the
structure of the disk in more detail.

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Hydrodynamic Instability in the Similarity Solution of Viscous Accretion Disks
Tomohiro Ono (Kyoto University)
Protoplanetary disks are the birthplaces of planets. Studying structures and evolutions ofprotoplanetary

disks

is

importantforplanetaryscience.

Itisgenerally

said

that

the

magneto-hydrodynamic instability is a dominant mechanism in disk evolution. However, when we
consider the region with steep pressure gradient such as a density bump or gap in disks, or an edge ofdisks, hydrodynamic instability can be important.
Protoplanetary disks evolve via turbulent viscosity, and their evolution is well represented by the modelof Lynden-Bell & Pringle (1974). In this model, the density profile of disks is analytically derived as thesimilarity solution. The similarity solution has an exponential cut off in surface density at the outermost
region, and pressure gradient gets steep in this region. For that reason, we investigate the stability of thesimilarity solution for hydrodynamic instability.
We first examine the stability of the similarity solution for rotational instability. Rotational instability is
local hydrodynamic axisymmetric instability. We find that the similarity solution is unstable against
rotational instability (Ono et al., 2014). We also investigate the stability of the similarity solution for
Rossby wave instability. Rossby wave instability is global hydrodynamic non-axisymmetric instability.
We perform linear perturbation analyses using the same methods as Li et al. (2000). In our poster, we willreport these results.

3rd DTA Symposium

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Disk Formation and Jet Driving in Collapsing Cloud Cores
Masahiro Machida (Kyushu University)
In the star formation process, the magnetic field and its dissipation process play an important role.
The magnetic field effectively dissipates and the rotation-supported disk forms inside the first core, while
the magnetic field coupled with the neutral gas again around the protostar and can drive high-velocity jet.
Non-axisymmetric structure develops in the disk due to gravitational instability and induces episodic
accretion onto the protostar. With the non-steady accretion, high-velocity jets show significant time
variability. I will talk about the disk formation and jet driving processes investigated by numericalsimulations.

3rd DTA Symposium

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Pre-main sequence evolution of low-mass stars: Effects of planet formation on stellar composition
Masanobu Kunitomo (Nagoya University)
Recent spectroscopic observations have revealed that the solar surface composition is peculiar
compared to most of solar-type stars. Refractory elements are scarce in the solar surface and this feature
would be related to planet formation process and pre-main sequence (PMS) evolution. One possible
scenario is that rocky planet formation removes them from accreting materials in the protosolar nebula
and the accretion pollutes the solar surface composition. However, if PMS stars are fully convective as inclassic studies, the effect of pollution is negligible.
In this study, we revisit the PMS evolution with the disk accretion, which is suggested by recent
multidimensional hydrodynamic simulations. Since the entropy of accreting materials in the disk
accretion can be much lower than that of the spherically symmetric accretion assumed in classical studies,
the internal structure of PMS stars in the disk accretion can be different.
We calculated the PMS evolution using a one-dimensional stellar evolution code MESA with modelingthe entropy of accreting materials. We found that the PMS evolution is greatly affected by the accreting
material’s entropy and the deuterium content. The surface convective zone (CZ) of PMS stars formed by
the low-entropy accretion can become shallow at 3 Myr, which is one order of magnitude faster than theclassical theory. Since this is faster than the typical disk lifetime (~6 Myr), we conclude that the stellar
surface composition can be affected by the formation of rocky objects (e.g., planetesimals, terrestrial
planets) in protoplanetary disks, if the accreting materials' entropy and the deuterium content are low.
Finally, we discuss that the shrink of CZ is also important for the orbital evolution of close-in planets via
tidal interaction and the updated PMS evolutionary tracks have a potential to change the estimated stellar
age and mass.

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Protoplanetary Disk Observations at Radio Wavelengths
Laura Perez (NRAO)
Protoplanetary disks surrounding young stars are the birthplaces of planets. With the advent ofsensitive observations and together with developments in theory, our field is making rapid progress inunderstanding the process of planet formation. In this review, I will describe how the evolution of
protoplanetary disks is traced by observations of their dust and gas components, and I will present recent
observational results that elucidate key aspects of the planet formation process, particularly focusing on
observations at the sub-mm, millimeter, and centimeter-wave regime. This wavelength range is alreadyproviding a plethora of new results, thanks to improvements in sensitivity brought forward by VLA andALMA.

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Chemical Processes in Protoplanetary Disks
Hideko Nomura (Tokyo Institute of Technology)
Thanks to recent development of infrared and radio observations, it has become possible to detectvarious kinds of molecular lines from protoplanetary disks. These lines give us information of thephysical and chemical structure of the disks. Statistical studies of molecular line observations from disks
will help us to understand the origin of the diversity in exoplanetary systems. In this talk I will review
recent observations of molecular lines and chemical modelling of protoplanetary disks, focusing on some
topics related with planet formation process and chemical evolution. For example, observations ofmolecular lines are useful to understand gas motion in the disks, which affects chemistry and line
spectrum of molecules. Also they can be a tracer of ionization degree as an indicator of magnetorotational
instability in the disks. Studies of environmental effects on chemistry in disks, such as inner holes andirradiation from nearby massive stars, will be useful for analysing varieties of disks which will lead tovarieties of planetary systems formed in the disks. Also, understanding distribution and formation
processes of water and organic molecules in the disks will be practical to understand the origin ofmaterials in our Solar System and other planetary systems.

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Analytical Formulas of Molecular Ion Abundances and N2H+ Ring in Protoplanetary Disks
Yuri Aikawa (University of Tsukuba)
We investigate the chemistry of ion molecules in protoplanetary disks, motivated by the detection of
N2H+ ring around TW Hya. While the ring inner radius coincides with the CO snow line, it is notapparent why N2H+ is abundant outside the CO snow line in spite of the similar sublimation temperaturesof CO and N2. Using the full gas-grain network model, we reproduced the N2H+ ring in a disk model withmillimeter grains. The chemical conversion of CO and N2 to less volatile species (sink effect hereinafter)
is found to affect the N2H+ distribution. Since the efficiency of the sink depends on various parameterswhich are not well constrained, we also constructed the no-sink model; the total (gas and ice) CO and N2
abundances are set constant, and their gaseous abundances are given by the balance between adsorption
and desorption. Abundances of molecular ions in the no-sink model are calculated by analytical formulas,which are derived by analyzing the full-network model. The N2H+ ring is reproduced by the no-sinkmodel, as well. The 2D (R-Z) distribution of N2H+, however, is different among the full-network modeland no-sink model. The column density of N2H+ in the no-sink model depends sensitively on thedesorption rate of CO and N2, and the flux of cosmic ray. We also found that N2H+ abundance can peak at
the temperature slightly below the CO sublimation, even if the desorption energies of CO and N2 are thesame.

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Non-equilibrium Ionization Degree and MRI in Protoplanetary Disks
Yuri Fujii (ELSI)The magnetorotational instability (MRI) is thought to be the main mechanism of angular momentum
transport in protoplanetary disks. Also, a disk wind caused by an MRI turbulence is expected to play
important roles in disk evolution. When a disk has plenty of dust grains, in general, the timescale ofchemical reactions governing MHD effects is much smaller than the dynamical timescale, so we can use
the equilibrium ionization degree for MHD simulations. However, when the abundance of tiny dust grains
is small or near the disk surface, the chemical timescale could be longer than the dynamical timescale.
Thus, it is important to consider the non-equilibrium ionization degree in those cases.
We implemented the calculation scheme for time-dependent ionization degree that is developed by Fujii
et al., (2011) into the Athena MHD code and performed three dimensional local shearing box simulations.
When the disk has mostly dissipated, we find that the ionization degree in the surface layer becomes
smaller than the equilibrium solution. This is because the disk wind lifts the poorly ionized gas in thelower layers to the surface layers. This effect may be important in the MHD and chemical evolution of
protoplanetary disks.

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Gas dynamics in disks: planet signatures and dynamical instabilities.
Wladimir Lyra (Caltech/JPL)
Recently, high angular resolution images obtained with the Combined Array for Research inMillimeter-wave Astronomy (CARMA) and with the Atacama Large Millimeter Array (ALMA) havebecome available, showing a plethora of puzzling asymmetries in the outer reaches of protoplanetarydisks that beg for explanation. The presence of planets is a particularly attractive interpretation for
explaining these asymmetries, since they generally match the range of structures predicted byhydrodynamical models of planet-disk interactions, namely, gaps, vortices and spirals. If that is indeed
the case, the observed asymmetries would provide a tantalizing laboratory to study planet-disk interaction
and planet formation. On the other hand, circumstellar disks are home to a myriad of hydrodynamical
processes, which bring about turbulence and structure formation, generally also matching those predictedby the presence of planets. In this talk I will review the state of the art and recent advances in gas
dynamics in disks with and without planets, and examine the observational evidence under the light ofour current theoretical understanding to help decide between the competing interpretations.

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The Origin and Fate of Rings in HL-Tau: Diversity of Planet Formation Mechanisms
Shu-ichiro Inutsuka (Nagoya University)
Protoplanetary disks are supposed to be the sites of planet formation, and thus, understanding of theevolution of the disk is crucial in understanding of the planet formation. Recent ALMA observation
revealed a remarkable multiple ring structure in a protoplanetary disk around HL Tau. Prior to thisobservation, Takahashi & Inutsuka (2014) proposed a possible formation of multiple ring structures by
secular gravitational instability in the case of weak turbulent diffusion. This talk describes the condition
for this to occur in detail and discuss the further evolution of the rings. A possible scenario for theformation of rocky objects at outer regions of the disks is outlined and contrasted with the other formation
scenarios.
[Reference]“Two-component Secular Gravitational Instability in a Protoplanetary Disk: A Possible Mechanism for
Creating Ring-like Structures”
Sanemichi Z. Takahashi & Shu-ichiro Inutsuka (2014)
The Astrophysical Journal Vol. 794, 55 (arXiv:1312.6870)

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Collsion simulation of sintered icy aggregates
Sin-iti Sirono (Nagoya University)
In the outer part of a protoplanetary nebula, the main component of solid is ice. Major species of ices
are H2O, CO, CO2, CH4 and NH3. Grain aggregates are formed from these ices and cores of Jovian
planets are eventually formed from the icy aggregates. Because the ices are volatile, slight temperature
increase is enough to lead to sublimation. Sublimed ice molecules preferentially recondense on the neckbetween adjacent grains. This process is called sintering. Mechanical properties of an icy grain aggregate
substantially changes due to condensed ice molecules. Without sintering, two icy grains are connected bysurface adhesion. In this case, a grain can freely roll on another grain without breakup of the connection
between grains. On the other hand, free rotation of a grain is hindered by the condensed molecules, andbreakup of a neck is required to rotate a grain.
We performed 2-D numerical simulations of collisions between sintered grain aggregates and found thatthe critical collision velocity, below which the growth of an aggregate is possible, decreases to 20 m/s
from 50 m/s without sintering. This decrease can be attributed to the change of the deformation mode ofan aggregate. Ductile deformation of an aggregate is possible because of the free rotation of grains. For
the sintered case, the deformation becomes brittle, leading to easy disruption of an aggregate.
Sublimation temperature depends on the ice species. Therefore, there are several distinct sintering regions
in a protoplanetary nebula. Necks grow in the sintering regions due to sublimation + condensation ofcorresponding icy spices. This simulation result indicates that there are several regions inside which thegrowth of grain aggregate is difficult and aggregate growth is only possible outside these regions.

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Electron Heating and Suppression of Magnetorotational Turbulence in Protoplanetary Disks
Shoji Mori (Tokyo Institute of Technology)
Turbulence plays an essential role in both the disk evolution and dust dynamics. One of promisingmechanism for generating vigorous turbulence is magnetorotational instability (MRI) whose activity
depends largely on the ionization fraction of the disk gas. It has recently been shown that the electric field
induced by the MRI turbulence can heat up electrons (electron heating) and thereby affect the ionization
balance. Especially, in a disk where dust grains are abundant, the electron heating decreases the electron
abundance and hence prevents further growth of MRI.
We investigate the actual distribution of the region in protoplanetary disks for the electron heating tooccur. We find that the “e-heating zone,” the region where the electron heating limits the saturation of the
MRI, extends out to 80 AU in the minimum-mass solar nebula with abundant submicron-sized grains.
This region is considerably larger than the conventional dead zone whose radius is ~ 20 AU in the samedisk model. We also estimate the MRI turbulent strength in the e-heating zone and find that the strength
at the midplane is suppressed down to ~ 10^-5 and 10^-3 at the inner and outer edge of the e-heating zone,
respectively. This implies that the MRI should be “virtually dead” in the e-heating zone. We will also
discuss the possibility of secular gravitational instability caused by the suppression of the MRI turbulence,
which may explain the multiple stripe structure observed in HL Tau.

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Observational Signatures of Planets in Protoplanetary Disks
Robin Dong (UC Berkeley)
It has been suggested that the spiral arms, gaps, and cavities recently discovered in protoplanetarydisks are produced by planets. To explore this scenario, we combine hydrodynamical calculations withthree-dimensional Monte Carlo Radiative Transfer simulations to study the observational signatures offeatures produced by planets, as well as disk activities, to check if they are consistent with observations.
We find that common gap opened by multiple planets can explain the observations of transitional disks.
Both the contrast ratio of the gaps and the wavelength dependence of the gap sizes are broadly consistent
with data. Planet-induced spiral density waves, however, do not appear to resemble the morphology of thedirectly imaged spiral arms at NIR wavelengths, and observations call for alternative explanations.
Finally, inspired by the recent ALMA release of the image of the HL Tau disk, we show that multiple
narrow gaps, well separated by bright rings, can be opened by 0.2MJ planets soon after their formation ina relatively massive disk.

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Disk-planet interaction and gap formation induced by a giant planet in protoplanetary disks
Kazuhiro Kanagawa (Hokkaido University)
A large planet is able to create a density gap along the planet's orbit in protoplanetary disks, due tothe disk-planet interaction. This gap formation significantly influences not only the orbital evolution ofplanet, e.g., transition from type I to slower type II migration, but also the mass growth of the planet. In
addition, the gap formation induced by a giant planet possibly explains the formation of the so-called
pre-transition disc with a ring gap. Hence, it is important to determine the relation between the planet
mass and the gap depth and width.
According to our analysis with the one-dimensional model, the propagation and damping of the density
wave excited by the planet is closely related to the gap depths and widths (Kanagawa et al 2015). We
performed a numerical simulation for a disk structure with a planet using FARGO, which is well-knownhydrodynamic code. Our results of the simulation indicate that a disk-planet interaction in the case of thelarge planet (such as Jupiter) is quantitatively different from the interaction in the case of the small planet.
In the large planet case, low-mode interactions ( in particular m=1 and 2) become larger than high-mode
interactions, whereas the high-mode interactions dominate the interaction in the small planet case. The
waves excited by a giant planet were thought to be instantly damped due to the non-linear dissipation.
However, as the same as the disk-planet interaction, we find that in the large planet case, the low-mode
waves becomes stronger than high-mode waves and are able to carry an amount of angular momentum toan outside of a gap region. This result might indicate a wide-gap formation induced by a planet.
In this talk, I will illustrate our results and discuss the disk-planet interaction and wave propagation withthe deep gap created by the giant planet. I will also talk about observational applications of our results.

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SEEDS : Review of direct imaging explorations of exoplanets/disks with Subaru
Nobuhiko Kusakabe (NAOJ)SEEDS, Strategic Explorations of Exoplanets and Disks with Subaru, is the first "Subaru Strategic
Program". We have 120 nights from 2009 and finished in January 2015. This project aims are (1) NIR
direct imaging and census of giant planets in the outer regions (10-100AU) around about 500 solar-type
and massive stars, (2) Exploring protoplanetary disks and debris disks for the origin of their diversity andevolution at the same radial regions, (3) Direct linking between planets and protoplanetary disks. In thistalk, I will review mainly direct imaging of the giant planets result.

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Probing the Dynamical History of Exoplanets: Spectroscopic Observations of Transiting Systems
Teruyuki Hirano (Tokyo Institute of Technology)
The origin of close-in giant planets is an enduring problem in the exoplanetary science. The key
process is the planet “migration” from their birth-places. Many migration scenarios have been proposed
and investigated both observationally and theoretically. One promising observational approach to probe
their dynamical history is to measure the obliquity of planet-hosting stars with respect to planetary orbits.
This is because different migration scenarios predict different outcomes for the stellar obliquity, and its
observations in the past have revealed that there are likely more than one migration channel that close-in
giant planets have experienced (e.g., Hebrard et al. 2010, Hirano et al. 2012). With the growing numberof systems characterized in term of stellar obliquity, our understanding on the dynamical history of
exoplanets has made significant progress. In this talk, I will present some of the key observational
techniques to measure the stellar obliquity, and review their observational status.

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Occurrence rate of giant planets around massive stars
Masashi Omiya (NAOJ)
The occurrence rate of giant planets would depend on the stellar mass. In particular, only a few giant
planets are found around stars with masses of more than 3 solar masses by the radial velocity method andthe rate around massive stars seems to be low. However, the lack of giant planets may be caused by anobservational bias because of small number of sample stars in radial velocity surveys. To clarify thestellar mass dependence of planetary systems and frequency around massive stars, we have been carry out
a radial velocity survey of giant stars with stellar masses of more than 3 solar masses. Based on our
survey over 3 years and results of other radial velocity surveys, we estimated occurrence rate of giant
planets around massive stars and discuss a relationship between the stellar mass and the occurrence rateof giant planets.

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Re-characterization a gravity-darkened and precessing planetary system PTFO 8-8695
Shoya Kamiaka (The university of Tokyo)
We reanalyse the time-variable lightcurves of the transiting exoplanetary system PTFO 8-8695, in
which a planet of 3 to 4 Jupiter mass orbits around a rapidly rotating pre-main-sequence star.
Both the planetary orbital period of 0.45 days and the stellar spin period less than 0.67 days are unusuallyshort, which makes PTFO 8-8695 an ideal system to check the model of gravity darkening and spin-orbit
nodal precession.
The previous analysis of PTFO 8-8695 assumed that the stellar spin and planetary orbital periods are thesame, but this condition is unlikely to hold in the actual system from the viewpoint of the long-term
stability of the system.
Therefore we extend the analysis by discarding the spin-orbit synchronous condition, and find threedifferent classes of solutions roughly corresponding to the spin-orbit nodal precession period of 200, 470,
and 830 days that reproduce the transit lightcurves observed in 2009 and 2010.
We compare the predicted lightcurves of the three solutions against the photometry data of a few percent
accuracy observed at Koyama Astronomical Observatory in 2014 and 2015, and find that the solution
with the 200 precession period is preferred even though preliminary.
Future prospect and advantages of this methodology to characterize the transiting exoplanetary systems
are also briefly discussed.

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High-resolution, global N-body similaton of planetary formation: Outward migration of a
protoplanet
Junko Kominami (Tokyo Institute of Technology)
We performed N-body simulations of planetesimal disk ranging from 0.7 AU - 4.0 AU which
includes the ice line. Runaway bodies form at the ice line first, where the solid surface density increases,
as well as at the inner edge. It is likely that the planetesimals around the runaway bodies accrete and a gap
in the planetesimal disk forms. We let the runaway bodies to grow to 0.1 M_Earth and restarted thesimulations. Full gravity calculation is included in the simulations. The runaway body moves outward
trasfering angular momentum of the planetesimals right outside the gap to its inside causing planetesimal
driven migration. The viscous stirring among the planetesimals increases the random velocity of theplanetesimals which the protoplanet encounters. The increase of the random velocity stops the migration.
However, if we consider more realistic model which includes gas drag, the random velocity would
decrease and the migration would continue. We present a model that forms the gas giant cores around theice line and make them migrate outward.

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Constraints on planetesimals implying from Itokawa dust particles
Shigeru Wakita (NAOJ)
Planetesimals are primordial bodies in the solar nebula, and the formation process of them has notbeen established. We performed the thermal modelling of the parent asteroid of Itokawa, which would beoriginally a planetesimal. The mineralogic studies of Itokawa dust particles revealed that those dust
particles resemble LL5 and/or LL6 type ordinary chondrites (Nakamura et al. 2011; Yurimoto et al. 2011).
There are constraints from these particles: they experienced thermal metamorphism at a peak temperatureof 800 degree Celsius but did not experienced > 1000 degree Celsius. The radiogenic and isotopic studies
indicate that the parent asteroid of Itokawa kept at 700 degree Celsius or higher at 7.6 Myr after Ca-Al
rich inclusions (CAI) formation. We assumed the parent body of Itokawa is the instantaneously-accreted
spherically symmetric one and the physical properties of the body are the same of those of LL6
chondrites. The one-dimensional heat conduction equations were solved numerically using a finite
difference method, with a main heat source of the decay energy of short-lived radionuclide(aluminum-26). We performed numerical simulations for the parent bodies which have variable sizes andaccretion times. Our results showed that the parent bodies of Itokawa would have been larger than 20 km
in radius at least to satisfy evidences from dust particles of Itokawa. The current Itokawa, which size isabout 0.5 km, originated in larger bodies, which was once disrupted and reaccumulated. We also foundthat the parent bodies of Itokawa accreted at a period between 1.9 and 2.2 Myr after CAI formation.
These values of Itokawa parent asteroids would constrain the size and accretion time of planetesimals.

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Dynamical Evolution of Planetary Systems:
Sourav Chatterjee (Northwestern University)
Following formation and gas disk dispersion, planetary systems can evolve through several
dynamical processes over billion year timescales, the age of typical planet host stars. These processes
alter the orbital properties of these planets. Under certain configurations, dynamical processing of orbits
may also result in changes in the planets' structural properties via tidal evolution and physical collisions.
In my talk I will review these processes with a focus on specific classes of observed planetary systems,
different from each other through their orbital properties, and how dynamical processes could havecreated them.

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Impact of stellar encounters on planetary systems
Steven Rieder (RIKEN)
Stars and planets generally form in large groups: star clusters and associations. In this birthenvironment, the density of stars is much larger than in the later stages of a star's life, when the cluster
has evaporated. This also results in a much higher chance of encounters between stars.
When in such an encounter the distance between stars is small enough, it can have a strong impact onplanets and circumstellar disks: possibly leading to migration of planets or even the disruption of thesystem. To quantify the importance of encounters on the final appearance of planetary systems, we needto study the effect of stellar encounters of various parameters (mass ratio, closest approach). Also, weneed to know how often such encounters occur, by investigating different birth conditions for the stars(e.g. number of stars in the star cluster, initial density and survival time of the cluster).
I study these aspects by means of simulations. The Astrophysical Multipurpose Software Environment
AMUSE (www.amusecode.org) can combine different physical aspects (e.g. gravity, gas dynamics andstellar evolution) over the different physical scales relevant to this problem. In my current model, I
include gravity on the scale of planetary systems, star clusters and the galaxy, as well as stellar mass loss.

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Planet Formation and Debris Disks
Hiroshi Kobayashi (Nagoya University)
The circumstellar disks observed around several hundred main sequence stars are mainly gas poor,
faint disks, which are called debris disks. They are mostly revealed by excess infrared emission aroundthe stars. In a planetesimal disc, collisional coagulation of kilometer or larger planetesimals produces asmall number of large bodies, oligarchies. Leftover planetesimals are strongly stirred by oligarchies,
resulting in the violent collisions between planetesimals. The collisional fragmentation of planetesimals
may form a debris disk. We aim to determine the properties of the underlying planetesimals in debris
disks by numerically modelling the coagulation and fragmentation of planetesimal populations. We findthat a radially narrow planetesimal disc is most likely to result in a debris disk that can explain the trendof observed infrared excesses of debris disks around G-type stars, for which planet formation occurs only
before 100 million years. Planetesimal disks with underlying planetesimals of radii ~100 km at ~ 30 AU
most readily explain the Spitzer Space Telescope 24 and 70 micron fluxes from debris disks aroundG-type stars.

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Gravitational Instability in Early Disk Evolution and the Formation of Clumps, Companions, andFree Floating Objects
Basu Shantanu (University of Western Ontario)
I review a series of works that solve the problem of protostellar disk formation and evolution
self-consistently from the collapse of a prestellar core. At early times the disk may be massive and driven
episodically into gravitational instability due to infall from the parent cloud core.
Instability leads to the formation of gaseous clumps, essentially first cores, that can continue to accrete
matter but generally also migrate inward. This leads to a migrating embryo scenario for early disk
evolution. Most clumps migrate to the center and are sheared apart, leading to luminosity bursts from thecentral young stellar object. However, some clumps can carve out a gap in the disk and survive in stableorbits. Others may be ejected from the system through interaction with other clumps. I also discussobservability of clumps in disks with ALMA.

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The revised criterion for the self-gravitational fragmentation of protoplanetary disks
Sanemichi Takahashi (Tohoku University)
Recent direct-imaging observations of planetary-mass objects far away from the central stars aresupposed to be emphasizing the importance of the self-gravitational fragmentation in the early
evolutionary phase of protoplanetary disks. This process may provide a formation mechanism of binarystars, brown dwarfs, and gaseous giant planets. Thus it is important to investigate the detailed condition
for the fragmentation of the protoplanetary disks. So far, the condition for the fragmentation has beenthought that the disk cooling timescale is comparable to its dynamical timescale. Gammie (2001) firstly
showed this condition, and many subsequent works (e.g., Rice et al. 2005, Stamatellos and Whitworth2009) seem to advocate this fragmentation condition. Since this condition is simple and useful, many
theoretical works (e.g. Rafikov 2005) on the evolution of the protoplanetary disks have used thiscondition.
However, there are the several works that seem to contradict the fragmentation criterion. For example,
Kratter et al. (2010) or Tsukamoto et al. (2015) shows the cases in which the fragmentation does notoccur even if the cooling time is small enough. On the other hand, Machida et al. (2010) shows that the
fragmentation can occur even when the cooling is inefficient. Therefore, the simple cooling criterion forthe disk fragmentation is not reliable for the realistic condition for the fragmentation of protoplanetarydisks.
In this work, using the two-dimensional numerical simulation and the linear stability analysis of the spiralarms, we propose a new, reliable condition for the fragmentation of the protoplanetary disks. We perform
two-dimensional numerical simulations that take into account the effect of the irradiation of the central
star and radiation cooling of the disk, and precisely investigate the structure of the spiral arms formed in
the protoplanetary disks. As a result, we find that the Toomre’s Q parameter "in the spiral arms", Q_spiralis the important parameter for the fragmentation. The new condition for the fragmentation is that ""thespiral arm fragments when Q_spiral < 0.6 is satisfied in the region two times as long as the width of the
spiral arms"".
We confirmed this fragmentation condition found in the numerical simulations can be obtained from thelinear stability analysis of the self-gravitating spiral arms. We will discuss the relation between our new
criterion and the previous cooling criterion and clarify the shortage of the previous cooling criterion

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Understanding Kepler's Super-Earth's & Sub-Neptunes
Eric Lopez (University of Edinburgh)
Recent surveys have uncovered a large new population of super-Earth and sub-Neptune sized planets.
Understanding these planets poses a fundamental test for models of planet formation and evolution. I will
review the possible origins and compositions of these planets and the constraints that can be provided bymodels of planetary structure and evolution. I will discuss the transition between rocky super-Earths andgaseous sub-Neptunes, the possible compositions of the sub-Neptunes, and the role that atmosphericphoto-evaporation plays in sculpting these populations.

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Atmospheric Study of Exoplanets by Transmission Spectroscopy
Akihiko Fukui (NAOJ)
Atmospheric composition of exoplanets can provide an important clue to the planetary formation
histories. Planetary atmospheres can be probed by means of transmission spectroscopy, which measures
the transit depth of a transiting planet as a function of wavelength. So far, several atoms (Na, K) andmolecules (H2O, CO) have been detected by this technique in a number of exoplanets. On the other hand,flat or smooth transmission spectra have also been observed in some planets, which indicates that theseplanets are probably covered by a cloud or haze layer. Studying the nature of cloudy and hazy atmosphere
has become an important topic aiming at detecting the molecular features buried under the clouds andhaze and understanding the condition of cloud/haze formation. In this keynote talk, I review theatmospheric study of transiting planets focusing on the latest results including our works.

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Future Missions of Transit Surveys and Characterizations
Norio Narita (NAOJ)
Thanks to previous planet surveys, we have learned that there are diverse planets. Especially NASA's
Kepler mission discovered thousands of planet candidates and revealed that small sized planets are quite
common in the Universe. One weakness of the Kepler mission was it mainly targeted stars too far away
for further characterization studies. Future transit survey missions thus aim to find transiting planets
orbiting solar neighbor stars. Such planets are suitable for further characterization studies, such asatmospheres, orbits, and so on. One already ongoing transit survey mission is K2, which is 2nd epoch
mission of the Kepler. And the next flagship mission will be Transiting Planet Survey Satellite (TESS),
led by MIT and NASA. Ground-based facilities are preparing various instruments for follow-up
observations for those planets which will be discovered by K2 and TESS. In this talk, I will summarize
the future transit survey missions and ongoing efforts for ground-based follow-up observations.

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Infrared Doppler planet search for Earth-mass planets
Bun'ei Sato (Tokyo Institute of Technology); Masashi Omiya (NAOJ)
To detect Earth-mass planets using the Doppler method is expected as a future step for understanding
the planetary systems and planet formation mechanisms in the universe. However, because of tiny signal(0.1m/s) caused by Earth-mass planets around solar-type stars compared with the stellar noise (~1m/s) inradial velocity variations, it is very difficult to confirm the existence of such planets using optical Doppler
instruments with current technologies. On the other hand, new infrared Doppler instruments optimized toprecise radial velocity measurements have been planed and constructed to search for Earth-mass planets
around low-mass stars. The infrared Doppler planet searches using the infrared instruments are able toperform more efficient radial velocity surveys of M-type main sequence stars and thus choose very
low-mass stars as targets of the their observations, and also can reduce the stellar noise in the radial
velocity variations. Moreover, low-mass stars are attractive targets to detect Earth-mass planets in the
habitable zone, because the habitable zone of low-mass stars is located at close-in orbits and Doppler
signals from the planets are relatively large (>1m/s). Thus, infrared Doppler planet searches have usefuland interesting advantages for detecting Earth-mass planets.
On these background, we are planning to conduct a new planet search of low-mass stars using a new
infraRed Doppler instrument for the Subaru telescope (IRD). The IRD is composed of a very stablenear-infrared high dispersion spectrograph and a precise wavelength (Doppler-shift) calibrator using alaser-frequency comb. IRD is installed on the telescope in 2015 and observations of our planet searchusing IRD will be started in 2016. The main goals of the planet search are to detect Earth-mass planets in
the habitable zone and to understand statistical properties, formation and habitability of extrasolar
planetary systems around low-mass stars.
Based on our suitable observing plan and results of theoretical population synthesis, we performed aobserving simulation of our planet search and estimated expected numbers of detectable planets in ourobservation. For a five year observation, we expect discoveries of more than 50 planets including morethan 30 planets with 1-5 Earth-masses and ten Earth-like planets in the habitable zone. In this talk, we
introduce IRD, our observing plan and simulation, and also expected scientific results to all participants.

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Exoplanet Researches at the NINS Astrobiology Center (ABC)
Motohide Tamura (UTokyo & NAOJ)
I will introduce the roles and researches at the Astrobiology Center of NINS, which has been justfounded in this April.

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Participants:
InvitedVardan Adibekyan (IA-Porto) vadibekyan@astro.up.pt

7

Eiji Akiyama (NAOJ) eiji.akiyama@nao.ac.jp

9

Shantanu Basu (University of Western Ontario) basu@uwo.ca

37

Sourav Chatterjee (Northwestern University) sourav.chatterjee@northwestern.edu

34

Robin Dong (UC Berkeley) rdong2013@berkeley.edu

26

Akihiko Fukui (National Astronomical Observatory of Japan) afukui@oao.nao.ac.jp

40

Teruyuki Hirano (Tokyo Institute of Technology)

29

Eiichiro Kokubo (NAOJ) kokubo@th.nao.ac.jp

8Nobuhiko Kusakabe (NAOJ) nb.kusakabe@nao.ac.jp

28

Zhi-Yun Li (University of Virginia) zl4h@virginia.edu

11

Eric Lopez (University of Edinburgh) elopez@roe.ac.uk

39

Wladimir Lyra (JPL/Caltech)

22

Masahiro Machida (Kyushu University) machida.masahiro.018@m.kyushu-u.ac.jp

16

Norio Narita (NAOJ/Astrobiology Center) norio.narita@nao.ac.jp

41

Hideko Nomura (Tokyo Institute of Technology) nomura@geo.titech.ac.jp

19

Laura Perez (NRAO) lperez@nrao.edu

18

Nami Sakai (RIKEN) nami.sakai@riken.jp

10Motohide Tamura (UTokyo & NAOJ) motohide.tamura@nao.ac.jp

43

Session chair
Yuri Aikawa (University of Tsukuba) aikawa@ccs.tsukuba.ac.jp

20

Shigeru Ida (Tokyo Institute of Technology)
Shu-ichiro Inutsuka (Nagoya University) inutsuka@nagoya-u.jp

23

Kohji Tomisaka (NAOJ) tomisaka@th.nao.ac.jp
OralYuri Fujii (ELSI) yuri.f@elsi.jp

21

Shoya Kamiaka (The university of Tokyo) kamiaka@utap.phys.s.u-tokyo.ac.jp

31Kazuhiro Kanagawa (Hokkaido University) kanagawa@lowtem.hokudai.ac.jp

27

Hiroshi Kobayashi (Nagoya Univ.) hkobayas@nagoya-u.jp

36

Junko Kominami (Tokyo Institute of Technology) kominami@mail.jmlab.jp

32

Masanobu Kunitomo (Nagoya University) kunitomo.masanobu@c.mbox.nagoya-u.ac.jp

17

Shoji Mori (Tokyo Institute of Technology) mori.s@geo.titech.ac.jp

25

Steven Rieder (RIKEN) steven@stevenrieder.nl

35

Sin-iti Sirono (Nagoya Univ.) sirono@eps.nagoya-u.ac.jp

24

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Oral
Sanemichi Takahashi (Tohoku University) sanemichi@astr.tohoku.ac.jp

38

Yusuke Tsukamoto (RIKEN) yusuke.tsukamoto@riken.jp

12

Shigeru Wakita (NAOJ) shigeru@cfca.jp

33

PosterKazsushi Okada (the University of Tokyo) kokada@ioa.s.u-tokyo.ac.jp

14

Tomohiro Ono (Kyoto University) ono.t@kusastro.kyoto-u.ac.jp

15

Yuji Matsumoto (NAOJ) yuji.matsumoto@nao.ac.jp

13

Attendees
Hitomi Furuya (Tsukuba) hfuruya@ccs.tsukuba.ac.jp
Ayaka Ito (Hosei University) ayaka.ito.3x@hosei.ac.jp
Masaki Iwasawa (RIKEN) cc67803@gmail.com
Kenji Kurosaki (The University of Tokyo) kkurosaki@eps.s.u-tokyo.ac.jp
Kento Masuda (The University of Tokyo) masuda@utap.phys.s.u-tokyo.ac.jp
Ryohei Nakatani (The University of Tokyo) r.nakatani@utap.phys.s.u-tokyo.ac.jp
Yoko Oya (University of Tokyo) oya@taurus.phys.s.u-tokyo.ac.jp
Soonyoung Roh (Ibaraki University) syroh@mx.ibaraki.ac.jp
KangLou Soon (Ibaraki University) 14nd402n@vc.ibaraki.ac.jp
Elizabeth Tasker (Hokkaido University) tasker@astro1.sci.hokudai.ac.jp
Yi Yang (SOKENDAI (The Graduate University for Advanced Studies)) yi.yang@nao.ac.jp
Yuxin Xue (The University of Tokyo) yuxin@utap.phys.s.u-tokyo.ac.jp
Seiji Zenitani (NAOJ) seiji.zenitani@nao.ac.jp
SOC
Misato Fukagawa (NAOJ) misato.fukagawa@nao.ac.jp
Yasuhiro Hasegawa (NAOJ; Chair) yasuhiro.hasegawa@nao.ac.jp
Fumitaka Nakamura (NAOJ) fumitaka.nakamura@nao.ac.jp
Masashi Omiya (NAOJ) omiya.masashi@nao.ac.jp
LOC
Yasuhiro Hasegawa (NAOJ; Chair) yasuhiro.hasegawa@nao.ac.jp
Masashi Omiya (NAOJ) omiya.masashi@nao.ac.jp
Masahiro Onitsuka (SOKENDAI/NAOJ) masahiro.onitsuka@nao.ac.jp
Takashi Shibata (The University of Tokyo) shibata.takashi@nao.ac.jp
Misako Tatsuuma (NAOJ) misako.tatsuuma@nao.ac.jp