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SUMMARY:Chemical networks for Protoplanetary Disk Gas Dynamics
DTSTART;VALUE=DATE-TIME:20200514T091000Z
DTEND;VALUE=DATE-TIME:20200514T093000Z
DTSTAMP;VALUE=DATE-TIME:20240704T115619Z
UID:indico-contribution-48@meetings.aip.de
DESCRIPTION:Speakers: Xuening Bai (Tsinghua University)\nI will discuss a 
 few applications requiring coupling chemistry with gas dynamics in protopl
 anetary disks. The most common application is to obtain the level of ioniz
 ation\, which determines the coupling between gas and magnetic fields. In 
 the bulk disk\, as far as ionization is concerned\, equilibrium chemistry 
 holds unless sub-micron sized grains are depleted. This allows magnetic di
 ffusivities to be obtained from a pre-computed look-up table based on a co
 mplex chemical network\, although magnetic diffusivities could have non-tr
 ivial dependence on magnetic field strengths due to small dust grains. Mor
 e interesting applications involve the transport of chemical species over 
 dynamical timescales\, such as those important for heating/cooling in the 
 disk atmosphere\, which requires explicitly evolving a (reduced) chemical 
 network with gas dynamics. We further show that a complex network can be r
 educed to a network with ~20-30 species with ~50-60 gas-phase reactions th
 at still reasonably reproduces the abundances of most major species of int
 erest in the disk atmosphere of the bulk midplane region. However\, the in
 termediate layer is more complex\, which may pose a challenge to chemo-dyn
 amical studies.\n\nhttps://meetings.aip.de/event/1/contributions/48/
LOCATION:Leibniz Institute for Astrophysics Potsdam (AIP) Lecture Hall
URL:https://meetings.aip.de/event/1/contributions/48/
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