Abstracts:


Here you should find the abstracts of all registered participants (version 23rd Oct, not the latest->Program):
 
 
 
Abstracts German-Japanese meeting 
 
Note: Schedule: Alexander "Sasha" Krivov (can only come Friday) 
 
      1. Jürgen Blum 
Per aspera ad planetas – there is hope that we will finally understand
planetesimal formation 
 
SESSION: PLANET FORMATION (Planetesimals) 


  After decades of modeling and experimental work on the growth from
  microscopically small dust particles to multi-kilometer-sized planetesimals, there
  are currently three competing scenarios on the market: (1) coagulation of dust to
  pebble-sized agglomerates, followed by sequences of instabilities which
  concentrate the dust particles until gravitation instability forms planetesimals, (2)
  direct collisional growth over the bouncing and fragmentation barriers to
  planetesimal sizes through the effect of mass transfer in collisions between very
  large and very small bodies, and (3) direct collisional growth without any barrier
  to planetesimal sizes, aided by the enhanced stickiness of sub-µm-sized water-
  ice particles. In my presentation, I will present these three planetesimal-formation
  models, including the empirical evidence from laboratory experiments they are
  based upon, and will also discuss the pros and cons of them as well as
  observational constraints, which can help to solve the mystery of planetesimal
  formation.  
   
      2. Jeroen Bouwman, MPIA 
  Characterization of planetery atmospheres from space. 
   
  SESSION: EXO-PLANETS (Atmospheres) 
   
  The Hubble and Spitzer Space Telescopes have revolutionized the observational
  characterization of exo-planets by detecting infrared emission and absorption
  from hot Jovian atmospheres. These detections have stimulated extensive
  theoretical work on the atmospheric structure and emission of these planets.
  Constraining the model predictions for infrared emission from hot Jovian
  atmospheres is an important motivation for current and future observing
  programs. Spectral characterization of hot Jovian exo-planets is a high priority
  and is essential for understanding atmospheric composition and properties. In
  this presentation I discuss the current observational capabilities with Spitzer and
  HST and give an outlook into future JWST observations. 
   
      3. Wolfgang Brandner 
Characterisation of cool brown dwarf and planetary atmospheres 
 
SESSION: EXO-PLANETS (Atmospheres) 
 
 
Today more than 1,500 exoplanets are known. The majority are giant planets
detected by radial velocity or transit observations, yielding information on
exoplanet masses, orbital periods, and bulk densities (and hence average
compositions). The determination of the atmospheric properties like overall
metallicity, chemical composition and mixing, vertical temperature profile, and
cloud coverage and constituents is considerably more challenging. Directly
imaged planets offer the advantage that they are at relatively large distances
from their host star, and hence are subject to considerably less radiative forcing
than closer-in planets. In addition, unlike the majority of the transiting planets,
directly imaged planets are also more readily accessible at all orbital phases. In
this talk I will present some of our recent observational results, which enable us
to test atmospheric models, and to constrain atmospheric properties of cool
brown dwarfs and exoplanets. 
 
    4. Cornelis Dullemond 
Observing dust traps with ALMA 
 
SESSION: DISKS (Observations) 
 
Abstract: Among the most striking observations of protoplanetary disks with the
new ALMA array is the lopsided ring structures in a number of transition disks.
The most famous examples at present are the IRS 48 disk in which there is a
very bright kidney shaped continuum blob on one side of the star, and the HD
142527 disk in which there is a banana shaped half-ring around the star. In both
cases the emission originates from dust grains. I will discuss a theoretical
interpretation of these lopsided structures in terms of a huge Rossby vortex in
which dust particles are trapped. Dust trapping in vortices was predicted almost 2
decades ago and now appears to be observed in real disks. However, further
observational tests, in particular with the new longer baselines of ALMA, will have
to be conducted to confirm this.  
 
    5. Hidenori Genda 
Collisions in Extrasolar Systems 
 
SESSION: PLANET FORMATION (Protoplanets) 
 
Collision is a fundamental process of planet formation in extrasolar planetary
systems as well as our solar system. Here we focus on many types of collisions
between planetesimals, protoplanets, super-Earths, and gas giant planets. We
will show our recent results of numerical simulations. For example, in collisions
between planetesimals, we re-evaluated the critical impact energy for
catastrophic disruption, which affects the growth of protoplanets, and revealed
that it was about a half order of magnitude smaller than the previous studies
expected. Some types of collisions between super-Earths or gas giant planets
would change their compositions, such as water-rock or envelope-core ratios. 
 
 
    6. Jun Hashimoto  
Near-Infrared Imaging Observations of Transitional Disks by the Subaru/
SEEDS project 
 
SESSION: DISKS (Observations) 
 
SEEDS is a strategic project in the Subaru telescope exploring exoplanets and
circumstellar disks around 500 stars in the near-infrared wavelengths. The
project has started in 2009 and will be completed in this year. Here, we review
the project and summarize the major results especially in the survey of
protoplanetary disks by near-infrared polarimetric imaging. In observing
protoplanetary disks, we mainly focus on transitional disks known as a
protoplanetary disk with a cavity in a central region of a disk. Disk-planet
interaction would be one of intriguing interpretations potentially responsible for
such a cavity-stracture. Thus, transitional disks would be unique samples for
understanding planet formation in a disk. 
As results of tens of observations in transitional disks, we have resolved fine
structures in disks such as spirals, gaps, and dips at a radius of tens AU possibly
due to gravitational interactions with unseen planet(s). These results may support
planet formation at a wide orbit, e.g., GJ 504 b at 43 AU. We also found
differences in structures of a cavity observed in the near-infrared and
(sub-)millimeter wavelengths, i.e., a clear cavity in (sub-)millimeter wavelengths
while no cavity in near-infrared wavelengths. The different behavior between
small (sub-micron size) and large (millimeter size) dust grains at the cavity-wall
sculpted by planet(s) could result in observing differences. Finally, we mention
our scientific activities in ALMA based on SEEDS data. 
 
    7. Artie P. Hatzes 
Detecting Short-period, Earth-mass planets in the Presence of Activity
Noise 
 
SESSION: EXO-PLANETS (Detection) 
 
The radial velocity (RV) jitter due to stellar activity can often be the limiting factor
in our ability to detect Earth-mass planets with the Doppler method. For highly
active stars this intrinsic variability can have amplitudes of a few to tens of m/s. I
introduce the Floating Chunk Offset method for detecting short-period low mass
exoplanets in the presence of activity noise. In this method RV data with good
temporal sampling are divided into chunks with time intervals shorter than the
expected periods from activity. An orbital fit is then made at a given period
allowing the velocity offsets in the chunks to vary. This method has been
employed on transiting planets with known periods. The FCO method can also
be used as a periodogram that acts as an effective "low-pass" filter of activity
noise thus allowing planets with unknown orbital periods to be detected. The
FCO method is applied to RV data for the transiting rocky planets CoRoT-7b and
Kepler-78b. The resulting K-amplitude due to Kepler-78b is slightly lower than
published values and implies a planet mass of 1.31 ± 0.24 M_Earth. The
nominal planet density of 4.5 ± gm cm^-3 is consistent with a low iron structure
(Moon-like) although the error is large enough to encompass an Earth-like
structure. More RV data are needed to distinguish between the models. 
 
    8. Th. Henning, J. Bouwman, D. Semenov. T. Albertsson 
Water: From Disks to Planets 
 
SESSION: DISKS (Observations) 
 
 
I will shortly summarize recently obtained  observational constraints on the
distribution of water vapour in protoplanetary disks. The talk will present the
spectroscopic discovery of water ice in disks around Herbig Ae stars at far-
infrared wavelength with Herschels. We will use this discovery to constrain the
formation pathway of water ice. In addition, I will discuss the origin of water on
Earth using chemical models for the solar nebula including turbulent mixing. 
 
 
    9. Shigeru Ida  
Orbital evolution of clumps formed by disk instability  
-implications for wide separation direct-imaged Jupiters  
 
SESSION: PLANET FORMATION (Fragmentation) 
 
We have studied orbital evolution of clumps formed by disk instability in outer
disk regions. The detection of wide separation jupiters by direct imaging
challenges conventional core accretion model and revived disk instability model
has been proposed for formation of these planets. However, hydrodynamical
simulations suggest that the clumps formed by disk instability rapidly migrate
inward. Because hydrodynamical simulations cannot follow the orbital evolution
on long timescales, we followed the evolution by orbital calculation, taking into
account dynamical friction and disk turbulence. We will show that final orbital
distributions of the clumps to discuss origin of wide separation direct-imaged
Jupiters.  
 
    10. Masahiro Ikoma 
Bulk and atmospheric composition of transiting low-mass exoplanets and
their origins.  
 
SESSION: EXO-PLANETS (Atmospheres) 
 
Recent transit measurements of exoplanets have revealed that there are a
significant number of low-density low-mass planets with short orbital periods. I
will talk about our recent theoretical studies of accumulation and secondary loss
of the atmosphere of short-period low-mass planets. Also, to gain deeper
understanding of the composition of short-period exoplanets, we have recently
done modeling of the atmosphere and, furthermore, performed multi-wavelength
transit measurements with several Japanese telescopes. So I want to talk about
our recent status of the characterization of the atmosphere of several transiting
exoplanets.  
 
 
    11.Shu-ichiro Inutsuka  
The Formation and Early Evolution of Protoplanetary Disks: A Hybrid
Scenario of Planet Formation 
 
SESSION: DISKS (Modelling) 
 
The formation and early evolution of protoplanetary disks are described in this
talk. Recent advance in the modeling with resistive magneto-hydrodynamical
codes with various numerical techniques has enabled our understanding on the
formation of protostars with outflows/jets and the formation of protoplanetary
disks in a self-consistent manner from molecular cloud cores. This provides
improved description for the realistic environments for planet formation in the
gaseous disks. We find that gaseous planetary-mass objects can be formed by
gravitational instability in the regions that are de-coupled from the magnetic field
and surrounded by the injection points of the magneto-hydrodynamical outflows
during the formation phase of protoplanetary disks.           Magnetic de-coupling
enables massive disks to form and these disks are subject to gravitational
instability, even at ~10 AU. The frequent formation of planetary mass objects in
those disks suggests the possibility of constructing a hybrid scenario of planet
formation, i.e., the rocky planets form later under the influence of the giant
planets in the protoplanetary disk. Our recent N-Body simulations of the new
scenario shows a new mechanism by which resultant rocky planets possibly
gravitationally push the giant planet towards the central stars. This "crowding-
out" mechanism may explain the observed lDiack of companion planets in HJ
systems. 
 
    12. Viki Joergens 
The formation of free-floating planets 
 
SESSION: EXO-PLANETS (w. Disks?) 
 
We show that the coolest known object that is formed in a star-like mode is a
free-floating planet. We discovered recently that the free-floating planetary mass
object OTS44 (M9.5, ~12 Jupiter masses, age ~2 Myr) has significant accretion
and a substantial disk. This demonstrates that the processes that characterize
the canonical star-like mode of formation apply to isolated objects down to a few
Jupiter masses. We detected in VLT/SINFONI spectra that OTS44 has strong,
broad, and variable Paschen beta emission. This is the first evidence for active
accretion of a free-floating planet. The object allows us to study accretion and
disk physics at the extreme and can be seen as free-floating analog of accreting
planets that orbit stars. Our analysis of OTS44 shows that the mass-accretion
rate decreases continuously from stars of several solar masses down to free-
floating planets. We determined, furthermore, the disk mass (30 Earth masses)
and further disk properties of OTS44 through SED modeling based on far-IR
Herschel data. We find that objects between 14 solar masses and 0.01 solar
masses have the same ratio of the disk-to-central-mass of about 0.01. Our
results indicate that OTS44 is formed like a star and suggest that the increasing
number of young free-floating planets and ultra-cool field T and Y dwarfs are the
low-mass extension of the stellar population. 
 
    13.Lisa Kaltenegger 
What can we really observe? Biosignatures on rocky planets and the
observable concept of the Habitable Zone 
 
SESSION: EXO-PLANETS (Atmospheres) 
 
In recent literature several claims have been made on extension of the Habitable
Zone as well as detectability or confusion on biosignatures on rocky planets.
Using a versatile 1D atmosphere model I will show a range of observable
biosignatures in transmission as well as emergent flux for a range of rocky
planets from Mini- to Super-Earths in the Habitable zone and discuss the HZ
concept. We will concentrate on recently discovered planets around cool stars as
well as the range of changes in a planet’s atmosphere due to the host star. 
 
    14. Hajime Kawahara 
Characterization of Exoplanets with High-contrast and High-Dispersion
Instruments on Extremely Large Telescopes 
 
SESSION: EXO-PLANETS (Detection)          
 
High-contrast instruments with future planned 30-40 m class telescopes such as
TMT, GMT, and E-ELTs will expand our knowledge of exoplanets. I will talk about
our recent study of characterization techniques of  exoplanets assuming these
instruments. One is the feasibility study of the oxygen 1.27 micron feature of
planets in the HZ around the lath-type stars. We investigate the noise from
terrestrial atmosphere for the 1.27 micron, especially night airglow of terrestrial
oxygen. We found that its emissivity significantly decreases an order of
magnitude by midnight. The future detectors for which the detection contrast is
limited by photon noise can detect this feature (Kawahara+2012 ApJ 758, 13).
We also consider an application of the high-contrast instruments  to the
spectroscopic detection of close-in planets (e.g. Brogi+2012 Nature 486, 502,
Rodler+2012 ApJL 753,25) with the high-dispersion instruments.  So far, CO and
water have been detected for nearby hot Jupiters. The high-contrast instruments
will extend the target to warm Juptiers and Neptune-size planets with the 1 mas
rms tip-tilt correction (Kawahara+ ApJS submitted arXiv:1404.5712). The tip-tilt
error is crucial for this type of observations. If we can correct the tip-tilt error
within 0.3 mas (rms), we have ~30 times larger gain in the S/N.  It will enable us
to perform precise measurements of the planetary radial velocity, which can be
used for detections of the planetary wind and rotation for the close-in planets(e.g.
Kawahara ApJL 760, 13).   
 
    15.Hubert Klahr 
The Formation of Planetesimals in Starving Mode: Zonal Flows and
Vortices in Circumstellar Disks 
 
SESSION: PLANET FORMATION (Planetesimals) / DISKS (Modelling) 
 
 
The formation of kilometer-sized planetary building bricks, called planetesimals,
is still a hotly debated problem. However a quantitative model on when and
where what sizes of planetesimals do form is the key to any self consistent
formation model for gas giants as well a terrestrial planets. 
 
A pure hit and stick model of dust grains faces several adversaries: from drift
barrier, to bouncing and fragmentation barrier to finally the 10km barrier. Thus,
models have been invoked that lead swiftly to 100km sized planetesimals from
centimeter sized objects via turbulent concentration and gravitational collapse. In
this talk I will highlight the role of zonal flows in magneto-hydrodynamical (MHD)
active regions of the disk and vortices in the MHD-dead zones. In the latter radial
and vertical stratification are the key of understanding the hydro-dynamical
stability of these disks. The fact that these features are able to scratch the tiniest
amount of small dust together in an amount sufficient, to trigger a streaming and
gravitational instability enables us to work on a size distribution for initial
planetesimals that resembles observational findings in the asteroid and Kuiper
belt. 
 
    16.Willy Kley 
Circumbinary Planets: Their properties and formation 
 
SESSION: PLANET FORMATION / DISKS (Modelling) 
 
 
 Circumbinary planets form a special subclass of exoplanets where the planets
orbit around a central binary star. Due to the presence of a secondary, the
circumbinary discs are dynamically excited and the planet formation process is
made more difficult than around single stars. Additionally, their subsequent
evolution is influenced by the disc dynamics. In the talk I will summarize the
observational properties of circumbinary planets and will present recent results in
modelling such systems. 
 
    17. Hiroshi Kobayashi 
Importance of collisional fragmentation in planet formation 
 
SESSION: PLANET FORMATION / DISKS (Modelling) 
 
Runaway and oligarchic growth produces a large planetary embryo in each
annulus of a protoplanetary disk. Planetesimals stirred by large embryos have
great random motions, resulting in collisional fragmentation between
planetesimals. Further collisions between fragments grind them down until
fragments of ~10m are removed by radial drift due to gas drag. As a result, the
embryo growth is significantly stalled by collisional fragmentation. On the other
hand, the collisional fragmentation might explain the size distribution of minor
bodies in the Solar System and debris disks. I will discuss the formation condition
for planets, asteroid belt, and debris disks, taking into account collisional
fragmentation. 
 
    18. Eiichiro Kokubo 
The Basic Scaling Laws of Terrestrial Planet Formation 
 
SESSION: PLANET FORMATION (Embryos) 
 
The recent exoplanet surveys show that small close-in planets are more common
than hot Jupiters in the Galaxy. Most of them are considered as terrestrial (rocky)
planets. Thus it becomes increasingly important to generally understand the
formation of terrestrial planets.    
In the standard scenario of terrestrial planet formation the final stage is the giant
impact stage after the dispersal of a gas disk where protoplanets or planetary
embryos formed by oligarchic growth collide with one another to complete
planets. We have been investigating this stage by using N-body simulations. In
the present paper, we review the basic scaling laws of terrestrial planet formation
and discuss the formation of close-in super-Earth systems.   
 
    19. Alexander V. Krivov (only Friday) 
Debris Disks - First Lessons from Herschel 
 
SESSION: DISKS (Observations) 
 
 
Debris disks, belts of invisible planetesimals and their observable dust, are
thought to be remnants of the planet formation process. These disks have been
observed at far-infrared wavelengths in several large-scale and smaller programs
of the Herschel Space Observatory. Herschel observations have revealed the
presence of debris disks around at least 20% of stars across and post the main
sequence, and increased the number of spatially resolved disks from about two
dozens to approximately one hundred. Resolved images along with densely
sampled SEDs allow one to more tightly constrain the properties of the disks.
First statistical analyses of Herschel-resolved disks suggest a two-component
structure (a Kuiper-like belt plus an asteroid-like belt) to be more common than a
single-component architecture. The disk radii do not appear to correlate with the
stellar luminosity, which might pose additional constraints on the planetesimal
formation mechanisms. In-depth collisional modeling of a few selected bright,
well-resolved disks uncovers some previously unexpected trends, too. The disks
of A-type stars (e.g., Vega, beta Pic, HR 8799) are compatible with an active
collisional cascade in a narrow, massive, Kuiper-like planetesimal belt with a
pronounced inner gap and a broad dust halo extending outward. In contrast, the
disks of solar-type stars (q1 Eri, HD 207129, HIP 17439) show sharper outer
edges and an additional emission closer to the star. This emission can be
equally well explained by inward drag of dust inward from a single narrow
planetesimal belt, dust production across an extended planetesimal disk, and an
additional inner disk. In all cases, the models suggest low dynamical excitation
of the main belt, i.e. disks that are collisionally quiescent rather than active. It
remains unclear, however, which mechanism is actually at work in these
systems. Nor is it clear what causes the difference between the disks of earlier-
and later-type stars, and to what extent possible planets in the disks are
responsible for the observed disk properties. 
 
     20.Luigi Mancini 
Photometric follow-ups of transiting exoplanets with ground-based
medium-class telescopes  
 
SESSION: EXO-PLANETS (Detections) 
 
It is now well ascertained that those extrasolar planets that transit in front to their
parent stars deserve extensive follow-up observations because they are the only
ones for which we can directly measure all their physical parameters. These
information currently provide the best route to constructing the mass-radius
diagram of exoplanets, which channels the theoretical formation/evolution
models in the right path. However, many of the discovered transiting planets do
not have high-quality light curves, so their physical properties are poorly known.
In this perspective, we are leading a large program to obtain ultra-high-precision
photometry of transit events, which are analyzed to accurately measure the
physical properties of know planetary systems. Besides measuring and refining
the physical properties of the planets and their parent stars, we also try to obtain
additional information from the light curves, by identifying particular features of
the systems (e.g. stellar activity) and investigating the composition of the
planetary atmospheres by transmission photometry. In my contribution, I will
present several observational strategies that we adopt to achieve these goals. 
 
    21.Yamila Miguel 
Hot rocky to gas planets: How host stars and realistic UV flux change the
detectable features for Mini-Neptunes and rocky atmospheres 
 
SESSION: EXO-PLANETS (Atmospheres) 
 
Recent ground and space surveys resulted in the detection of many hot
extrasolar planets. These planets are interesting targets for current and future
observations, therefore, addressing their atmospheric structure and composition
is a major issue and the aim of my work. For the hot potentially rocky exoplanets
with an outgassed atmosphere we developed a simple approach to find their
atmospheric composition according to their observable data (radius, semi-major
axis and stellar effective temperature). For hot mini-Neptune and giant planets's
atmospheres, we calculated an atmospheric grid that links astrophysical
observable parameters - orbital distance and stellar type - with the atmospheric
species expected in exoplanet atmospheres. We link a 1D code that calculates
the atmospheric thermal structure with a photochemical model that includes
disequilibrium chemistry and explore the effect of empirical model parameters on
the results, for planets around a wide range of stellar types from F to M, including
the effect of high FUV radiation on their atmospheres. Our results can be applied
to current and future observations to characterize exoplanet atmospheres and
serves as a reference to interpret atmospheric retrieval analysis results. 
 
    22. Mordasini Christoph 
Connecting microphysics during formation with exoplanet observations:
the impact of grain opacity in atmospheres of protoplanets 
 
SESSION: PLANET FORMATION (Embryos) 
   
The number of extrasolar planet with an accurately measured mass and radius
has recently increased very rapidly. This has allowed to constrain for the first time
observationally the hydrogen/helium fraction as a function of a planet's mass.
This relation is of high interest for planet formation theory: it allows to constrain
the mechanisms that govern gas accretion during formation. A key quantity
controlling gas accretion is the opacity due to tiny dust grains suspended in the
atmosphere of protoplanets. If it is high, only tiny primordial H/He envelopes can
be accreted. In the opposite case, already low-mass cores can accrete much H/
He. In this talk I will present a newly developed analytical model for the grain
opacity. It predicts very low grain opacities. I will then shown the population wide
consequences of different magnitudes of the grain opacity. Low grain opacities
lead to gas-rich low-mass low-density planets, not unlike the ones detected in
large numbers by the Kepler satellite. I will show that the observed mass-radius
relationship indeed also points to low grain opacities in protoplanetary
atmospheres. The consequences for giant plant formation are discussed as well
as for the transition from solid to gas-rich low-mass planets. 
 
    24.Makiko Nagasawa 
Outcomes of planet-planet scattering 
 
SESSION: PLANET-FORMATION (Embryos) 
 
Planet-planet scattering is one of the mechanisms to explain relatively large
eccentricities of observed exojupiters. Typical fates of orbital instability of the
three planet systems are ejections of a planet, planet-planet collisions, and
planet-star collisions. Our group performed numerical simulations of planet-
planet scatterings including tidal effects and showed a close encounter of a gas
giant and a star can cause a hot-jupiter and the close encounter of gas giants
can form binary planets. We will show the detailed results of numerical
simulations of planet-planet scattering and discuss about their implications for
future observations.  
 
    25.Taishi Nakamoto,  
Formation of solid materials in evolving solar nebula  
 
SESSION: PLANET-FORMATION (Planetesimals) 
 
We discuss the formation and evolution of solid materials seen in solar system
bodies such as CAIs, chondrules, chondritic matrix, etc. These materials are
thought to be formed in solar nebula, thus we discuss their formation in the solar
nebula taking into account the formation and evolution of the solar nebula itself.
In addition, we discuss a possible scenario of the agglomeration of dust particles,
the formation of planetesimals, and the growth of protoplanets, in the context of
the solid materials formation and evolution. 
 
    26. Hideko Nomura 
Complex Organic Molecules in Protoplanetary Disks  
 
SESSION: DISKS (Observations) 
 
We investigate the synthesis of complex organic molecules (COMs) in
protoplanetary disks using a large gas-grain chemical network including COMs
together with a 2D steady-state physical model of a disk irradiated by UV and X-
rays from the central star. We find COMs are efficiently formed on cold and warm
grains in the disk midplane via grain-surface reactions through efficient migration
of icy species on grain surface. Radiation processing on ice forms reactive
radicals and helps build further complexity. Part of the icy molecules are
photodesorbed into gas and their transition lines become observable. We also
perform ray-tracing calculations to predict line spectra of complex organic
molecules and suggest CH3OH should be readily observable in nearby
protoplanetary disks with ALMA. We also find the grain-surface abundances
predicted by our calculations are consistent with those derived from cometary
comae observations providing an evidence for the hypothesis that comets and
other planetesimals formed via the coagulation of icy grains in the Sun's natal
disk. 
 
    27.Satoshi Okuzumi 
Electric-field heating of plasmas and its effect on 
magnetorotational turbulence in protoplanetary disks 
 
SESSION: PLANET FORMATION / DISK (Modelling) 
 
The electric conductivity of the gas is a key parameter of magnetohydrodynamics
(MHD) in low-temperature astronomical objects like protoplanetary disks. It is
commonly assumed that the conductivity is independent of the strength of the
electric field (as measured in the neutral-gas rest frame), and this assumption
leads to the conventional linear Ohm's law. However, the linear Ohm's law breaks
down when the electric field is so strong that heating of plasma particles is non-
negligible. In fact, an order-of-magnitude estimate based on the results of recent
MHD simulations suggests that the plasma heating is indeed significant in MRI-
driven turbulence in some outer parts of protoplanetary disks. We construct a
charge reaction model that takes into account plasma heating by electric fields as
well as plasma capture by dust grains. We find that plasma heating leads to a
reduction of the ionization degree, and hence to an enhancement of the magnetic
resistivity, unless the electric-field strength is below the discharge threashold.
This occurs because the electron--grain collision frequency increasing with
increasing the random velocity of electrons. This effect may limit the saturatation 
amplitude of MRI-driven turbulence near the outer edge of the conventional dead
zone. 
 
    28. Andreas Quirrenbach, CARMENES Consortium  
CARMENES: Searching for Blue Planets Orbiting Red Dwarfs  
 
SESSION: EXO-PLANETS (Detection) 
 
CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-earths
with Near-infrared and opti-cal Echelle Spectrographs) is a next-generation
instrument currently under construction for the 3.5m tele-scope at the Calar Alto
Observatory by a consortium of eleven Spanish and German institutions (see
also Quirrenbach et al. 2010; 2012). CARMENES will conduct a 600-night
exoplanet survey targeting ~300 M dwarfs. An important and unique feature of
the CARMENES instrument is that it consists of two separate échelle
spectrographs, which together cover the wavelength range from 0.55 to 1.7 μm
at a spectral resolu-tion of R = 82,000. The spectrographs are fed by fibers from
the Cassegrain focus of the telescope. For late-M spectral types, the wavelength
range around 1.0 μm (Y band) is the most important wavelength region for radial
velocity work. Therefore, the efficiency of CARMENES will be optimized in this
range.  
The main scientific objective of the CARMENES project is to carry out a survey of
late-type main sequence stars with the goal of detecting low-mass planets in their
habitable zones (HZs). In the focus of the project are very cool stars later than
spectral type M4 and moderately active stars. In particular, we aim at being able
to detect a 2M⊕ planet in the HZ of an M5 star. A long-term radial velocity
precision of 1ms−1 per measure-ment will permit to attain such goals. For stars
later than M4 (M < 0.25M⊙), such precision will yield detec-tions of super-Earths
of 5M⊕ and smaller inside the entire width of the HZ. The CARMENES survey
will thus provide a comprehensive overview of planetary systems around nearby
Northern M dwarfs. By reaching into the realm of Earth-like planets, it will provide
a treasure trove for follow-up studies probing their habitability. 
 
    29.Sabine Reffert 
Giant Planet Occurrence Rate as a Function of Stellar Mass and Metallicity 
 
SESSION: EXO-PLANETS (Detection) 
 
Based on our precise Doppler survey of a sample of G and K giant stars, which
we have carried out at Lick Observatory over more than 12 years, we examine
the planet occurrence rate as a function of stellar mass and metallicity. In
particular, we probe the stellar mass range from about 1 to 3 solar masses, which
is neither being fully explored by main-sequence nor subgiant stellar samples.
We find the well-known planet-metallicity correlation, as well as a strong
dependence of planet occurrence on stellar mass. Interestingly, there is a peak in
the giant planet occurrence rate for masses between about 1.5 and 2.0 solar
masses. For masses in the range from 2.5 to 3.0 solar masses, the giant planet
occurrence rate drops rapidly to zero, at least for those giant planets to which
our survey is sensitive. We conclude that giant planet formation is suppressed
around higher mass stars, possibly due to faster disk depletion in combination
with a longer migration timescale.  
 
    30. Semenov Dimitry 
Importance of dynamical processes for chemical evolution of
protoplanetary disks 
 
SESSION: DISKS (modelling) 
 
Protoplanetary disks are birth sites of planetary systems. A better
characterization of their physical and chemical structure, which are needed to
understand initial phases of planet formation, is currently one the major goals of
modern astrophysics. Their studies are complicated by their compact sizes and
low masses, and their dynamical activity. In this presentation we investigate the
importance of dynamics on the chemical structure of disk's gas and dust. We find
that dynamics enhances abundances of many gas-phase species and ices,
particularly, complex hydrocarbons involved in slow X-ray-driven CO destruction.
Particularly affected by dynamics are the inner, planet-forming disk regions, with
strong gradients of temperature and high-energy radiation intensities. We show
how evolving chemistry affects the global C/O gas and solid composition and
why it may matter for planet formation processes. 
 
    31.Takanori Sasaki 
Re-entry of giant-impact fragments and early evolution of the Earth.  
 
SESSION: PLANET FORMATION (embryos) 
 
The late stages of Earth’s formation remain a mystery. No building blocks remain
in Earth’s orbit and no geological evidence is available for the first 700 million
years Earth’s history. Clues have been found, but some of them seem
paradoxical. Herein we propose that protoplanetary fragments produced by the
giant impacts may reconcile those apparently conflicting facts. Our new scenario
present an exhaustive framework of early evolution of terrestrial planets, and
impact our understanding of whether planets like Earth are common in extrasolar
systems as well. I’m looking forward to discussing with German researchers at
the meeting   
 
    32.Takayuki Muto 
Protoplanetary Disk Morphology and High-Resolution Imaging
Observations   
 
SESSION: DISKS (Observations) 
 
Understanding protoplanetary disks is important in understanding planet
formation processes.  Recent observations by Subaru and ALMA have revealed
that protoplanetary disks are rich in detailed structures, and the gas and dust are
distributed differently.  We present results of recent observations by ALMA and
Subaru and modeling efforts of protoplanetary disks.  We especially focus on
non-axisymmetric structures such as spirals or horse-shoe-like dust
condensations, and discuss what we can derive from such structures.  We also
mention about prospects of future high-resolution imaging observations by 30-
meter class telescopes or full ALMA capability. 
 
    33. Taku Takeuchi  
Transport of the Magnetic Flux in Protoplanetary Disks and Disk Evolution
via MHD Turbulence and/or Winds 
 
SESSION: PLANET FORMATION / DISKS (Modelling) 
 
I present our recent works on the transport of the magnetic flux which is originally
from the interstellar magnetic field and threads the disk. Then, I discuss disk
evolution that is controlled by the magnetic flux via MHD turbulence and/or
winds. Recent several MHD simulations have suggested that the mass accretion
rate driven by the MRI or disk winds is controlled by the magnetic flux threading
the disk. This means that quantifying the magnetic flux is essential for studies on
the disk accretion. We analyzed a simple model of the mean poloidal field in a
thin disk. We show that there is an upper limit on the magnetic flux threading the
disk, and consequently there is also an upper limit on the mass accretion rate. I
also discuss the evolution of protoplanetary disks whose accretion rates are
determined by the magnetic flux. An interest finding is that, contrary to previous
expectations, dead zones do not always suppress the mass accretion rate. Even
in an inner part where a dead zone exists, if the magnetic flux is high enough, the
mass accretion rate can be as high as or even higher than that at the outer active
region. Such stronger accretion at the inner part is expected especially at late
stages of disk evolution. This mechanism possibly explains an inner hole of some
transitional disks. 
 
    34. Hidekazu Tanaka  
Fluffy Dust Growth and Planetesimal Formation  
 
SESSION: PLANET FORMATION (Planetesimals) 
 
 
Planetesimal formation is one of the major problems in planet formation theory.
Rapid direct growth of fluffy icy dust is a hopeful model for planetesimal
formation. In this model, the key point is the mechanical property of dust
aggregates (i.e., their stickiness and compressibility). I will talk about recent
progress on dust aggregate simulations in our group and discuss planet
formation, too. 
 
    35. Motohide Tamura 
Subaru Direct Imaging Observations of Exoplanets and Brown Dwarfs 
 
SESSION: EXO-PLANETS (Detection) 
 
 
SEEDS (Strategic Explorations of Exoplanets and Disks with Subaru) is the first
Subaru Strategic Program, whose aim is to conduct a direct imaging survey for
giant planets as well as protoplanetary/debris disks at a few to a few tens of AU
region around 500 nearby solar-type or more massive young stars devoting 120
Subaru nights for 5 years. The targets are composed of five categories spanning
the ages of ~1 Myr to ~1 Gyr. Some radial velocity planet targets with older ages
are also observed. The survey employs the new high-contrast instrument
HiCIAO, a successor of the previous NIR coronagraph camera CIAO for the
Subaru Telescope. We describe the outline of this survey and present its results
on exoplanets and brown dwarfs. The survey has published ~30 refereed papers
by now. The main results on exoplanets are as follows: (1) Detection and
characterization of the most unequivocal and possible lowest-mass planet
around the Sun-like star, GJ 504b, via direct imaging. It is so  
far the only exoplanet whose atmospheric methane features make their color
“blue” among the other directly imaged “red”-color exoplanets. (2) Detection of a
super-Jupiter around the most massive star ever imaged, kappa And b. (3)
Detection of planet or brown dwarf around Sun-like star, GJ 758b, and several
brown dwarfs in Pleiades. (4) Detection of companions around retrograde
exoplanet, HAT-P-7B, which supports the Kozai mechanism for the origin of
retrograde orbit. Preliminary statistics in each category are also mentioned. 
 
    36. Mario Trieloff 
Compositional variety among planets: When and how were compositional
gradients established in the early solar system? 
 
SESSION: PLANET FORMATION (Planetesimals) 
 
Our solar system is clearly divided in rocky planetary bodies in the inner solar
system, and gas and ice giants planets in the outer solar system. 
While this roughly corresponds to expectations from condensation temperatures
prevailing in the solar nebula, governed by the protosun and protoplanetary disc
dynamics, many details concerning the compositional diversity of solar system
objects are unknown, even after decades of research in cosmochemistry. 
 
One important question is how homogeneous the initial disk material was,
particularly the dust component inherited from the interstellar medium (ISM).
While certain interstellar grains definitely represent isotopically anomalous
circumstellar dust, it is not clear, what their mass fraction in the ISM is, and what
fraction was homogenised in the ISM by evaporation and recondensation
processes. 
 
However, even if highly heterogeneous grain populations dominated the solar
nebula, large scale mixing of submicron sized interstellar grains should have
cancelled out large scale chemical heterogeneities. Indeed we know that certain
primitive extraterrestrial matter represented by CI chondrites represent a first
order average composition of solar or cosmic element abundances. 
On the other hand, there are chondrite classes that are characterised by 
1) moderately volatile element depletions 
2) intra-silicate (olivine/pyroxene) fractionation 
3) metal-silicate fractionation 
which is generally interpreted as being a result of (mainly thermal) processing in
the solar nebula, along with gas-solid phase separation before planet formation
started. 
 
While such fractionation processes within a protoplanetary disc are feasible,
there are mixing processes simultaneously at work, which should counteract
differentiation. 
For example, mixing   processes are evident from the presence of high
temperature material such as CAIs or refractory forsterites in cometary material,
implying radial transport form hot inner to the cold outer disk regions. 
 
The composition of volatile-rich exoplanets is frequently explained by planetary
migration processes, implying that their material could not have accreted in their
present day's orbital position. 
Such conclusions can only be properly established, if the chemical (and isotopic)
compositon of protoplanetary material in the respective feeding zones can be
modelled by means of (chemical) disc fractionation and counteracting radial
mixing processes at the preplanetary stage. 
 
    37.Roy van Boekel 
The link between planet formation and planet atmosphere spectra 
 
SESSION: EXO-PLANETS (Atmospheres) 
 
The composition of a planet and its atmosphere are governed by its formation
history in the circumstellar disk and its further evolution. During the early
formation phase a rocky core is formed, which may subsequently accrete a
gaseous envelope once the core mass succeeds a critical value, forming a giant
planet. While Hydrogen and Helium dominate the mass of the envelope and
atmosphere of giant planets, their spectral appearance is dominated by the
abundance of heavy elements needed to build spectroscopically active
molecules (e.g. water, methane). The molecular composition of mature exoplanet
atmospheres depends on the relative abundances of heavy elements in the
envelope, which follow from the accretion history during the formation phase. In
this talk we will present model calculations of the formation of giant planets,
following which kind of material is accreted depending on the formation location
in the disk. We will focus on the circumstances under which an oxygen-rich or a
carbon-rich chemistry results. We also show the resulting atmospheric spectra of
mature planets, and simulated observations of transiting systems with which the
discussed cases can be distinguished.”  
 
 
 
    38. Joachim Wambsganss 
Searching for Extrasolar Planets with Gravitational
Microlensing: Challenges and  Exciting Results  
 
SESSION: EXOPLANETS (Detection) 
 
Gravitational microlensing is a powerful method for the detection of extrasolar
planets. In particular its sensitivity to low mass planets and its potential for global
statistical analyses are highly relevant. The basics of this technique and its
current mode of operation  will be explained as well as its advantages and
disadvantages compared to other planet-search methods. About three dozen
microlensing planets have been discovered so far. A couple of microlensing
detections will be presented and reviewed in detail. A recent statistical analysis
on the Galactic abundance of extrasolar planets will be presented and discussed,
with particular emphasis on the result that “Planets are the rule, not the
exception ”. In a brief outlook, the immense potential of gravitational microlensing
for detections of Earth- and Mars-mass planets, of exomoons and of free-floating
planets will be highlighted. 
 
    39.Sebastian Wolf 
High-angular resolution observations and modeling of circumstellar disks 
 
SESSION: DISKS (Observation) 
 
Observations of circumstellar disks around young stars are the key to better
understand and to refine existing hypotheses for the various phases of the planet
formation process. I will present modeling approaches based on observations in
various wavelength ranges at low to high spatial resolution. Exemplary case
studies will be discussed which illustrate state-of-the-art observations and
subsequent radiative transfer modeling of protoplanetary and debris disks. 
 
    40. Wurm Gerhard 
Collisions of Small Bodies in Protoplanetary Disks: Cold, Hot, and Viscous 
 
SESSION: PLANET FORMATION (Planesimals) 
 
The physics of silicate collisions at moderate temperatures has been treated
extensively in the past decades showing the potential and limits in planetesimal
formation. The microphysics of more extreme environments with high and low
temperature has mostly been restricted to numerical modeling and only recently
emerges in experiments. We currently exploit some aspects here. We measure
ice contact forces for nm to µm grains, study the evolution of contact forces and
collisions with increasing temperatures toward 1000 K, and study collisions of
viscous particles as chondrule analogs. I will sketch our latest evolution on these
topics 
 
 
 










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