More than half thousand exoplanets have been observed, however, observations have so far been unable to confirm the
presence of planets caught in formation. Giant planets form in the inner, dense and gas-rich regions of the
circumstellar disks around young stars - at least this is what theory predicts. The inner R<5 AU region of disks
at 100pc are spatially unresolvable with recent instruments, but the near-infrared high-resolution spectroscopy of
CO is applicable to investigate these regions. In the first part of my presentation I will give a short summary on
the physics behind the formation of near infrared spectra of the disks. Next a novel method based on the distortions
of the CO molecular line profiles emerging from the protoplanetary disks will be presented. The method aims at
detecting a giant planet still embedded in a disk.
According to our numerical models the orbit of gas parcells become eccentric near the gap opened by the giant planet,
which causes both permanent and time-variable disturbances in the CO emission. Expanding our investigation to
systems where the companion mass is in the order of that of the central star, i.e. in case of young binaries, we
found that the orbit of gas parcels are eccentric everywhere in the disk. As a result, the CO line profiles are
permanently asymmetric because of a similar phenomenon that was found in planet embedded disks; this way the disk
eccentricity becomes measurable. It is known that core-accretion is severely affected by disk eccentricity, hence
the detection of an eccentric protoplanetary disk in a young binary system would constrain planet formation theories.
In the second part of my presentation I will show results of our numerical investigation on the development of the
circumprimary disk eccentricity and the CO line profile distortions.
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