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Book of Abstracts THE PHYSICS AND CHEMISTRY OF THE INTERSTELLAR MEDIUM Celebrating the first 40 years of Alexander Tielens' contribution to Science Book of Abstracts Palais des Papes - Avignon - France 2-6 September 2019 CONFERENCE PROGRAM Monday 2 September 2019 Time Speaker 10:00 Registration 13:00 Registration & Welcome Coffee 13:30 Welcome Speech C. Ceccarelli Opening Talks 13:40 PhD years H. Habing 13:55 Xander Tielens and his contributions to understanding the D. Hollenbach ISM The Dust Life Cycle 14:20 Review: The dust cycle in galaxies: from stardust to planets R. Waters and back 14:55 The properties of silicates in the interstellar medium S. Zeegers 15:10 3D map of the dust distribution towards the Orion-Eridanus S. Kh. Rezaei superbubble with Gaia DR2 15:25 Invited Talk: Understanding interstellar dust from polariza- F. Boulanger tion observations 15:50 Coffee break 16:20 Review: The life cycle of dust in galaxies M. Meixner 16:55 Dust grain size distribution across the disc of spiral galaxies M. Relano 17:10 Investigating interstellar dust in local group galaxies with G. Clayton new UV extinction curves 17:25 Invited Talk: The PROduction of Dust In GalaxIES C. Kemper (PRODIGIES) 17:50 Unravelling dust nucleation in astrophysical media using a L. Decin self-consistent, non steady-state, non-equilibrium polymer nucleation model for AGB stellar winds 19:00 Dining Cocktail Tuesday 3 September 2019 08:15 Registration PDRs 09:00 Review: The atomic to molecular hydrogen transition: a E. Roueff major step in the understanding of PDRs 09:35 Invited Talk: The Orion Bar: from ALMA images to new J. Goicoechea dynamic PDR models 10:00 [CII] optical depth and self-absorption in M17SW C. Guevara 10:15 Coffee break & Posters 11:15 Review: PDRs near and far: the extraordinary utility of M. Kaufman photodissociation region models 1 Time Speaker 11:50 The importance of the atomic history in time-dependent M. de Avillez simulations of the interstellar gas- from non-thermal to ther- mal distributions 12:05 The physical state of CO-dark gas in the Perseus arm M. Busch 12:20 Lunch break & Posters 14:30 The low-metallicity ISM of dwarf galaxies: the multiphase S. Madden structure and the CO-dark gas 14:45 The atomic envelope of molecular clouds as revealed by ma- J.D. Soler chine vision PAH 15:00 Spectroscopy of interstellar polyaromatic hydrocarbons and J. Bouwman their photoproducts 15:15 Unravelling spectral signatures and photochemical processes A. Petrignani of polycyclic aromatic hydrocarbons 15:30 Coffee break & Posters 16:25 Tracing PAH size in prominent nearby mid-infrared environ- C. Knight ments 16:40 Radioastronomical observations of PAHs and other aromatic B. McGuire species at the earliest stages of star formation 16:55 Formation process of small hydrocarbons in PDRs: gas M. Tiwari phase chemistry or fragmentation of polycyclic aromatic hy- drocarbons (PAHs)? 17:10 Review: Today's PAH model: four not so easy pieces L. Allamandola Wednesday 4 September 2019 08:15 Registration PAH 09:00 Review: Astro-PAHs: a journey from space to the labora- C. Joblin tory 09:35 PAHs on/in water ice: structures, energetics, and spec- J. Mascetti tra from FTIR experiments and a multi-method theoretical study 09:50 Photoionization of polycyclic aromatic hydrocarbons: con- P. Br´echignac tribution to the heating of the Interstellar Medium 10:05 Invited talk: ISM spectra from near- to mid-infrared T. Onaka 10:30 Coffee break & Posters 11:35 Experimental studies of the catalytic role of oxygen func- R. Jaganathan tionalized PAHs Ices 11:50 Review: From simple to complex molecules in interstellar A. Boogert ices 12:25 Ices in small dense molecular cores L. Chu 12:40 Formation of molecules on cold interstellar grains F. Dulieu 12:55 Lunch break & Free afternoon 2 Thursday 5 September 2019 Time Speaker 08:15 Registration Ices 09:00 Review: From astrochemistry to astrobiology? A few se- L. d'Hendecourt lected papers on cosmic ices evolution 09:35 SPHEREx: surveying the milky way in biogenic ices G. Melnick 09:50 Adsorption of volatile molecules on interstellar car- B. Mate bonaceaous analogs 10:05 Invited talk: Laboratory investigations on the chemical and M.E. Palumbo optical properties of interstellar ice analogs 10:30 Coffee break & Posters 11:30 Quantum chemistry computations as an interpretative and A. Rimola predictive tool for grain-induced astrochemical processes. The formamide formation case 11:45 The physics and chemistry on the surface of cosmic dust A. Potapov grains + 12:00 H2 and HCO formation at the interface with crystalline S. Pantaleone models of icy mantles: insights from periodic DFT-MD sim- ulations 12:15 Damaged water ice: an opportunity for reactivity? A. Markovits 12:30 Lunch break & Posters Astrochemistry 14:30 Review: Carbon chemistry in evolved stars J. Cernicharo 15:05 Invited talk: Molecular complexity in solar-type star form- B. Lefloch ing regions 15:30 IRAM hunt for hot corino and WCCC objects in the OMC- M. Bouvier 2/3 filament 15:45 First astrophysical detection of the helium hydride ion HeH+ R. Guesten 16:00 Coffee break & Posters 17:00 Astrochemistry of protoplanetary disks from an observa- C. Favre tional point of view 17:15 Modelling of the chemistry of protoplanetary disks M. Ruaud 17:30 Chemistry and isotopic ratios in intermediate redhisft molec- S. Wallstrom ular absorbers 17:45 The effect of circumstellar dust grains on the gas phase M. Van De Sande chemistry in AGB outflows 20:00 Social dinner 21:30 After dinner speaker M. Wolfire 3 Friday 6 September 2019 Time Speaker 08:15 Registration Astrochemistry 09:00 Review: Gas-phase chemistry in the interstellar medium: N. Balucani there is still much to learn 09:35 Prevalent complex organic molecules towards prestellar S. Scibelli cores in the Taurus star forming region 09:50 Invited talk: Grain surface chemistry and its impact on the S. Cazaux gas phase 10:15 A computational study of the reaction N(2D)+C6H6: impli- D. Skouteris cations for the upper atmosphere of Titan 10:30 Coffee break & Posters Future & Perspectives 11:00 Review: Future developments of IRAM instruments K. Schuster 11:25 Review: Observing facilities for astrochemistry: evolution T. de Graauw and future perspectives 11:50 Review: Astrochemistry: the next 40 years E. van Dishoeck 12:15 Closing talk T. Millar 4 ORAL CONTRIBUTIONS 5 Today's PAH model: four not so easy pieces Louis Allamandola1∗y 1 BAERI, NASA Ames Research Center { United States Over the past thirty-five years the interstellar PAH hypothesis has been tested, has had predictions borne out, and has been successfully applied to a surprising number of disparate astrophysical and astrochemical processes. Along the way, the PAH hypothesis became the PAH model. This progress has only been possible thanks to the close collaboration between laboratory experimentalists, astronomers, modelers and theoreticians. Due to the deep interdisciplinarity of the "PAH Problem" however, this progress has been made in ’fits and starts', and often in choppy, unconnected steps with the result that today's model is not yet as fully integrated into a whole as it can be. Adding to the complexity, since astronomical PAHs are nano-sized molecules, not particles, they play astrophysical and astrochemical roles that differ from those of grains. Given the information PAH spectra contain about the astronomical objects in which they are found, and the key roles they are now called upon to play in the astrophysics of many (if not most) objects across the Universe, sharpening the model as much as it can be sharpened is key to its full exploitation as a novel and far-reaching astronomical tool. This is particularly critical now with the anticipated launch of the James Webb Space Telescope (JWST ) in about two years. JWST 's combination of unprecedented sensitivity, spectral resolution, and wavelength coverage will make it possible, for the first time, to measure and fully characterize PAH spectra across the complete 1 - 28 µm range, the range in which the strongest PAH fundamental bands and associated features fall. Interstellar PAH mid-IR emission spectra form the foundation on which the entire PAH model rests. While great progress has been made in understanding the general spectroscopy of such large molecules, very significant challenges regarding important spectroscopic details remain. Similarly with PAH growth and destruction. Until recently the stepwise processes invoked to grow simple molecules containing a few carbon atoms to polycyclic aromatic structures and fullerenes were very general. Now there are a number of experimental and theoretical studies that show generalizations do not capture PAH growth, destruction and evolution well. Likewise with more complex chemistry involving PAHs. The recent, exciting discovery of benzonitrile in the cold core TMC-1 is the tip of an iceberg. Pun intended. Over the past decade or two, sophisticated experimental work has revealed some of the steps involved in the growth and destruction of PAHs in the gas. This depth of understanding does not yet hold for interstellar ice chemistry involving PAHs. It is critically important to gain this knowledge because a number of laboratory studies of interstellar ice analogs and models show that the inclusion of PAHs can profoundly influence ice chemistry and physics. Taken together, these gaps in our detailed knowledge severely limit what astronomical PAHs tell us today versus what they can tell us. This talk will touch on some of the recent laboratory advances and challenges in four areas: PAH spectroscopy, growth, destruction, and chemistry. ∗Speaker yCorresponding author: [email protected] 6 Gas-phase chemistry in the interstellar medium: there is still much to learn Nadia Balucani1∗y 1 DCBB, Universit`adegli Studi di Perugia { Perugia, Italy After the \scoundrels rule" according to which the formation of hydrides is due to processes occurring on the surface of the icy mantles of interstellar grains [1], it has been proposed that the entire set of interstellar complex organic molecules is actually formed by radical-radical recom- bination processes assisted by interstellar ice [2]).
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