<p class="MsoNormal"><span lang="EN-US">Super earths and sub-Neptunes account for a
large fraction of currently discovered exoplanets. Some of them may contain a
considerable amount of water, but many are thought to be dry. Pebbles
containing water ice accreted by the planetary core are thought to be the main
source of water content. However, during accretion, the planetary atmosphere
could become hot enough to sublimate the ice component and avoid direct accretion
of water. Meanwhile, vapors can also freeze out as ice grains, which will be
recycled back to the disk.</span></p><p class="MsoNormal"><span lang="EN-US"></span></p><p class="MsoNormal"><span lang="EN-US">We have implemented a new phase change
module in Athena++, which is able to follow the sublimation and condensation
processes. Combined with the recently developed multi-dust fluid approach
(Huang, Bai et al.), we conduct self-consistent hydrodynamic simulations to
study the effect of pebble sublimation in the atmosphere.<o:p></o:p></span></p><p class="MsoNormal"><span lang="EN-US">We find that the extent and the amount of
vapor that a planet is able to hold on to strongly depends on its location in
the disk (ambient temperature). When the sublimation front is far inside the
atmosphere, vapors tend to be locked deep in the atmosphere and keep accumulating.
On the other hand, when the sublimation front exceeds the (bound) atmosphere,
incoming pebbles can be fully recycled and the vapor content reaches a steady
value. Therefore, planets formed at the disk H2O snowline, may have limited
water contents.</span></p><p class="MsoNormal">
</p><p class="MsoNormal"><span lang="EN-US">The phase change module developed by us is
general and can be applied to different context. Regarding the planet-disk
interactions, accreting giant planets will heat up their surroundings, allowing
icy volatile released before the pebbles are accreted, which changes the
chemical inventory of the local disk. We have applied this model to understand
the spatial distribution of molecular line emission observed with ALMA.<o:p></o:p></span></p><p></p>