Invited Presentation

Molecular Line Observations of Protoplanetary Disks

Author(s):

Presenter: Hideko Nomura (Tokyo Institute of Technology)

Molecular line observations tell us information of not only
chemical but also physical properties of protoplanetary disks.
ALMA has made it possible to detect complex organic molecules
in the disks. In addition, our ALMA observations of CO isotopologue
lines show CO gas depletion even inside the CO snowline, which
suggests formation of larger and less volatile species on grain
surface. In addition, our model calculations predict that
destruction of carbon grains in hot surface layer very close
to the central star will lead to formation of more carbon-bearing
species and it can be testable by ALMA observations.
Water line emission is another interesting target, which will
be useful to locate the water snowline and constrain the initial
condition of planet formation in the disks. Our model calculations
show that water emission lines of water snowline tracer will be
detectable by ALMA observations. If I have time, I will briefly
talk about SO and H2S lines as a possible tracer of protoplanet
formation and icy planetesimal evaporation in the disks, too.