Workshops > PCMI in the JWST era : from fundamental data to observations

PCMI in the JWST era: from fundamental data to observations

Organisers: Benoît Tabone (benoit.tabone@universite-paris-saclay.fr), Emilie Habart (emilie.habart@universite-paris-saclay.fr), Emmanuel Dartois (emmanuel.dartois@universite-paris-saclay.fr), Alexandre Faure (alexandre.faure@univ-grenoble-alpes.fr), Sylvie Cabrit (sylvie.cabrit@obspm.fr)

Thursday, 27 October 8:30-12:00

Summary:

The upcoming JWST observations (starting in summer 2022) will enable decisive advance in our understanding of the interstellar and circumstellar medium by providing us with a unique combination of sensitivity and spectro-imaging capabilities in the near and mid-infrared (0.6-27micron). However, our previous experience with former missions (ISO, Spitzer, Herschel) demonstrates that a substantial modelling effort in tight collaboration with experimentalists and theoreticians has to be initiated prior to the first data analysis. This need is even more urgent for JWST data. The near and mid-infrared domain is indeed particularity rich in (i) ro-vibrational molecular lines that are sensitive to complex non-LTE processes (chemical and UV pumping, prompt emission, collisional excitation of highly excited levels), (ii) absorption features of ices and silicates, which depend critically on their structure and composition, (iii) aromatic and aliphatic infrared bands, which depend on complex radiative transfer effects and on the detailed structure of their carriers (PAH or hydrogenated carbonaceous nano-grains).

    In this emerging context, the PCMI community benefits from a unique position worldwide by gathering observers, modellers, and experts in laboratory experiments and molecular physics. The goal of this workshop is, therefore, to gather the PCMI community around the JWST programs in which French teams are involved, in order to maximize the scientific outcome of JWST in a very competitive context. In particular, we will:
1. Review the JWST programs in which French teams are involved (Early Release Science, Guaranteed Time, and Open Time). This will foster synergies between observers, and engage the physicists and chemists by informing them about the challenges that we will face for interpreting the data.
2. Survey the modelling tools that are already available, from the simplest models (e.g. slab models) to the most sophisticated ones.
3. Identify the existing physico-chemical data, and define the new needs raised by JWST in terms of laboratory experiments and theoretical calculations.
4. Foster the emergence of JWST Cycle 2 proposal (call early 2023), by gathering observers, modellers, theoreticians, and experimentalists.

Our program will cover a variety of astrophysical environments for which major breakthroughs are expected with JWST.

Organization

8h30-8h35: Introduction Benoît Tabone
8h35-9h15 Observations (Chair: Emilie Habart)
• PDRs : Alain Abergel (IAS)
• Disques : (TBA)
• Flots : Catherine Dougados (IPAG)
• Glaces et grains (milieux froids) : Jennifer Noble (PIIM)
9h15-10h00 Outils de modélisation (Chair: Sylvie Cabrit)
• PDRs (gaz) : Franck Le Petit (LERMA)
• Chocs et turbulence (gaz) : Benjamin Godard (LPENS)
• Transfert radiatif (grains) : Meriem El-Yajouri (IAS)

10h30-12h00 Données de laboratoire et calculs de physique moléculaire
(chair: Alex Faure & Emmanuel Dartois)
• Calculs de physique moléculaire (gaz) : Jérôme Loreau (KU Leuven) ; chimie état-à-état et collisions à haute énergie
• Glaces, grains : Jennifer Noble ; spectroscopie (phase & composition)
• AIBs : Christine Joblin (IRAP) ; expériences de laboratoire, propriétés optiques.