BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Modelling microphysics in MHD: ambipolar diffusion\, chemistry\, a nd cosmic rays DTSTART;VALUE=DATE-TIME:20200513T142000Z DTEND;VALUE=DATE-TIME:20200513T144000Z DTSTAMP;VALUE=DATE-TIME:20241101T160711Z UID:indico-contribution-3-57@meetings.aip.de DESCRIPTION:Speakers: Tommaso Grassi (USM/LMU)\nFrom molecular clouds to p rotoplanetary disks\, non-ideal magnetic effects are important in many ast rophysical environments. Indeed\, in star and disk formation processes\, i t has become clear that these effects are critical to the evolution of the system. The efficacy of non-ideal effects are\, however\, determined by t he complex interplay between magnetic fields\, ionising radiation\, cosmic rays\, microphysics\, and chemistry. In order to understand these key mic rophysical parameters\, we present a one-dimensional non-ideal magnetohydr odynamics code and apply it to a model of a time-dependent\, oblique\, mag netic shock wave. By varying the microphysical ingredients of the model\, we find that cosmic rays and dust play a major role\, and that\, despite t he uncertainties\, the inclusion of microphysics is essential to obtain a realistic outcome in magnetic astrophysical simulations.\n\nhttps://iaus37 9.aip.de/event/1/contributions/57/ LOCATION:Leibniz Institute for Astrophysics Potsdam (AIP) Lecture Hall URL:https://iaus379.aip.de/event/1/contributions/57/ END:VEVENT BEGIN:VEVENT SUMMARY:Consistent Microphysics in Protoplanetary Disk Simulations DTSTART;VALUE=DATE-TIME:20200513T135500Z DTEND;VALUE=DATE-TIME:20200513T141500Z DTSTAMP;VALUE=DATE-TIME:20241101T160711Z UID:indico-contribution-3-16@meetings.aip.de DESCRIPTION:Speakers: Lile Wang (Center for Computational Astrophysics\, F latiron Institute)\nConsistent time-dependent modeling of microphysics\, e specially thermochemistry and radiation-matter interactions\, is desired b y the studies on protoplanetary disks. In this talk\, I will introduce our GPU-accelerated numerical infrastructures for consistent microphysics co- evolved with (magneto-)hydrodynamic simulations. Their applications in the studies of protoplanetary disk dispersal processes will be elaborated\, i ncluding photoevaporation and magnetized wind-driven accretion mechanisms. Formation of disk substructures is also explored using our system\, empha sizing the necessity of non-ideal MHD consistently coupled with microphysi cs.\n\nhttps://iaus379.aip.de/event/1/contributions/16/ LOCATION:Leibniz Institute for Astrophysics Potsdam (AIP) Lecture Hall URL:https://iaus379.aip.de/event/1/contributions/16/ END:VEVENT BEGIN:VEVENT SUMMARY:A Post-Processing Pipeline for Proto-Planetary Disk Simulations (P PPPPDS) DTSTART;VALUE=DATE-TIME:20200513T133000Z DTEND;VALUE=DATE-TIME:20200513T135000Z DTSTAMP;VALUE=DATE-TIME:20241101T160711Z UID:indico-contribution-3-13@meetings.aip.de DESCRIPTION:Speakers: Jon Ramsey (Virginia Initiative on Cosmic Origins\, Department of Astronomy\, University of Virginia)\nI will present a new po st-processing pipeline for (magneto-)hydrodynamic simulations of protoplan etary accretion disks and results from its first application. By combining publicly available radiative transfer and astrochemistry tools\, we proce ss snapshots from radiative\, non-ideal MHD simulations of thermally-assis ted centrifugal outflows from disks (Gressel et al. 2020) to search for ob servational signposts of outflows which are accessible from current observ atories. In particular\, we compare synthetic observations from models wit h and without outflows to determine which transitions and chemical species can be used to distinguish between the two classes of models. We find tha t the shape of the line profiles\, and velocity asymmetries in moment 1 ma ps\, can discriminate between disks with and without outflows. By combinin g the synthetic observations with the full simulation data\, we can also p inpoint where emission from a particular line or species is coming from in the outflow and/or disk\, which can help us better understand existing an d future observations of disks and outflows.\n\nhttps://iaus379.aip.de/eve nt/1/contributions/13/ LOCATION:Leibniz Institute for Astrophysics Potsdam (AIP) Lecture Hall URL:https://iaus379.aip.de/event/1/contributions/13/ END:VEVENT BEGIN:VEVENT SUMMARY:The role of cosmic rays in protoplanetary disks and young exoplane tary systems DTSTART;VALUE=DATE-TIME:20200514T093500Z DTEND;VALUE=DATE-TIME:20200514T095500Z DTSTAMP;VALUE=DATE-TIME:20241101T160711Z UID:indico-contribution-3-50@meetings.aip.de DESCRIPTION:Speakers: Donna Rodgers-Lee (Trinity College Dublin)\nThe infl uence of magnetic fields in protoplanetary disk evolution depends sensitiv ely on the level of ionisation present. Protoplanetary disks are thought t o be only very weakly ionised which provides imperfect coupling to magneti c fields and influences disk dynamics. Understanding the sources of ionisa tion\, such as cosmic rays\, present in the disks underpins our overall un derstanding of how these systems evolve and form planets. \n\nHowever\, yo ung solar-type stars are very magnetically active and drive stronger stell ar winds that may shield protoplanetary disks from galactic cosmic rays\, thus losing an important source of ionisation. At the same time\, the incr eased magnetic activity of young stars suggests that protoplanetary disks\ , and young exoplanetary systems\, are bombarded by stellar cosmic rays\, or stellar energetic particles. I will present recent results from our mod el of cosmic ray transport in these systems and the chemical signatures th at we might expect from cosmic rays.\n\nhttps://iaus379.aip.de/event/1/con tributions/50/ LOCATION:Leibniz Institute for Astrophysics Potsdam (AIP) Lecture Hall URL:https://iaus379.aip.de/event/1/contributions/50/ END:VEVENT BEGIN:VEVENT SUMMARY:Chemical networks for Protoplanetary Disk Gas Dynamics DTSTART;VALUE=DATE-TIME:20200514T091000Z DTEND;VALUE=DATE-TIME:20200514T093000Z DTSTAMP;VALUE=DATE-TIME:20241101T160711Z UID:indico-contribution-3-48@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://iaus379.aip.de/event/1/contributions/48/ LOCATION:Leibniz Institute for Astrophysics Potsdam (AIP) Lecture Hall URL:https://iaus379.aip.de/event/1/contributions/48/ END:VEVENT BEGIN:VEVENT SUMMARY:Interpreting emission line diagnostics of disc winds DTSTART;VALUE=DATE-TIME:20200514T084500Z DTEND;VALUE=DATE-TIME:20200514T090500Z DTSTAMP;VALUE=DATE-TIME:20241101T160711Z UID:indico-contribution-3-9@meetings.aip.de DESCRIPTION:Speakers: Barbara Ercolano (USM/LMU\, Munich)\nWinds from plan et forming discs can be photoevaporative or magnetically driven. Both typ es of wind can remove mass from the disc and affect the surface density ev olution of the planet making material. A basic difference between these tw o types of wind is that magnetic winds\, unlike photoevaporative winds can also remove angular momentum and thus drive accretion in the system. Inde ed a departure from the classic alpha disc model is gaining momentum in th e field and is one of the main topics of this workshop. Unfortunately\, bo th photoevaporation and MHD numerical modes have yet to be observationally constrained and their relative contribution to the evolution of discs at various ages is still uncertain. In this contribution I will discuss curre ntly observed disc wind diagnostics and present past and current efforts i n modelling these lines using state-of-the-art theoretical models as well as analytical prescriptions.\n\nhttps://iaus379.aip.de/event/1/contributio ns/9/ LOCATION:Leibniz Institute for Astrophysics Potsdam (AIP) Lecture Hall URL:https://iaus379.aip.de/event/1/contributions/9/ END:VEVENT END:VCALENDAR