The observational data gathered by state-of-the-art astrophysical facilities provide our primary source of information towards a better understanding of the impact of the interstellar medium physics and chemistry on high redshift galaxies, on star and planet formation in the Milky Way, or on life emergence. Opening up new regions of discovery space through increased sensitivities, angular and spectral resolutions, polarimetry, survey speeds, multi-wavelength multi-carriers studies is essential to understand these fundamental question of astrophysics.

This 4-day workshop aims first at mobilizing the community on the observatories under construction or evolution and on long-term research and development activities, both for ground and space observatories.  It also aims at defining the scientific challenges of PCMI community within the next 5-15 years to define the space of parameters to be explored and the associated observatory characteristics.

The workshop will take place in Paris, at the CNES center (2 place Maurice Quentin, Paris) on October 18^th, 19^th and 20^th and at the Pierre and Marie Curie campus (Jussieu) on October 21^st.

Invited speakers for session 1 - Athena/XIFU

• Didier Barret (IRAP)                       Satellite and XIFU instrument
• Delphine Porquet (LAM)                 AGN (radio-quiet) and outflows
• Emmanuel Dartois (ISMO)                 X-ray / matter interaction
• Antoine Gusdorf (LPENS)               ISM Energetic phenomena

Invited speakers for session 2 - Approved or proposed facility

• Guy Perrin (INSU/CNRS)                 Introduction
• Pierre-Olivier Lagage (CEA)           Status and scientific goals of JWST
• Ludovic Montier (IRAP)                    Status and scientific goals of LiteBIRD
• Martina Wiedner (LERMA)               Status and scientific goals of OST and HSTDM
• Vianney Lebouteiller (CEA)            Status and scientific goals of LUVOIR
• Annie Hughes (IRAP)                      Status and scientific goals of PILOT/CO-PILOT
• Cécile Engrand (IJCLAB)                Status and scientific goals of sample return missions
• Maud Galametz (CEA)                    Status and scientific goals of APEX (CONCERTO/ARTEMIS)
• Emilie Habart (IAS)                           Status and scientific goals of ELT and VLTI
• Marc-Antoine Miville-Deschenes (CEA)  Status and scientific goals of SKA

Invited speakers for session 3 - Science cases and R&D

• Maryvonne Gerin (CNRS/INSU)          Introduction
• Francois Boulanger (LPENS)              Prospective on H2 imaging and spectroscopy
• Pierre Cox (IAP)                                  Prospective on studies of the ISM in galaxies
• Douglas Marshall (IRAP)                     Prospective on three-dimensional ISM studies
• Anaelle Maury (CEA)                           Prospective on studies of protostars proto-planetary disks and exoplanets
• Cecilia Ceccarelli (IPAG)                     Prospective on molecular studies
• Olivier Berne (IRAP)                            Prospective on PAH studies
• Marc Sauvage (CEA)                          Prospective on ISM Polarimetry science
• Karl Schuster (IRAM)                          Prospective on (sub)-mm radio-astronomy
• Christophe Risacher (IRAM)               Prospective on multi-beam detectors
• Alessandro Monfardini (Institut Neel)  The role of KID in future millimetre and sub-millimetre instruments
• Benjamin Quertier (LAB)                     Prospective on electronics R&D for ALMA and ELT
• Jean-Philippe Berger (IPAG)               Prospective on infra-red R&D
• Claudia Cicone (ITA Norway)              AtLAST - The Atacama Large Aperture Submm Telescope