Title: Exploring the signatures of cosmic ray feedback effects in galaxy ecosystems
Speaker: Ellis Owen (Osaka University)
Language: English
Link(s): https://www.ellisowen.org
Cosmic rays go hand-in-hand with violent and energetic astrophysical conditions. They are an active agent within galactic and circumgalactic ecosystems, where they can deposit energy and momentum, modify the circulation of baryons, and even have the potential to regulate star-formation on local and galactic scales. Their influence in galaxies can be probed using observable signatures across the electromagnetic spectrum, with high energy radiation being particularly important to determine their energy budget, feedback power and hydrodynamic effects. In this talk, I will discuss some of the astrophysical impacts hadronic and leptonic cosmic rays can have in and around galaxies, how their influence can be probed using signatures in X-rays and gamma-rays, and the opportunities soon to open-up that will allow us to map-out the multi-scale effects of cosmic rays in galaxies near and far.
Title: Protostars and protoplanetary disks with JWST: first results from the JOYS and MINDS programs
Speaker: Ewine van Dishoeck (Leiden Observatory, the Netherlands)
Language: English
This talk will present first results of the MIRI-MRS spectra of a number of protostars, T Tauri and brown dwarf disks resulting from the JOYS and MINDS GTO programs as well as a number of open time programs. Rich ice spectra are seen in dark clouds and the cold outer envelopes of protostars hinting at the presence of complex molecules in ices formed very early in the evolution. In young and mature disks, many lines from gaseous CO, H2O, CO2, C2H2 and HCN are found, but also surprising new molecules are detected. Together they point to a rich chemistry that is linked to the physical structure of the inner regions of these disks and thereby provides a unique diagnostic of it.
Background information: the 55 hr JWST Observations of Young protoStars (JOYS) GTO program (PI: van Dishoeck) uses MIRI to investigate the physical and chemical properties of two dozen protostars and their immediate environment. JOYS studies the physical characteristics of embedded disks, accretion signatures onto the protostars, feedback from the young protostars on their environment through primordial jets and outflows, as well as the chemical gas and ice constituents of the protostellar envelopes to feed the disks.
The goal of the 120 hr MIRI Mid INfrared Disk Survey (MINDS) GTO program (Th. Henning, I. Kamp co-PIs) is to use JWST to (1) investigate the chemical inventory of the terrestrial planet forming zone, (2) to follow the gas evolution into the disk dispersal stage, and to (3) study the structure of protoplanetary and debris disks in the thermal mid-IR. The program builds a bridge between the chemical inventory of planet-forming disks and the properties of exoplanets. In total, about 50 targets (Herbig Ae stars, T Tauri stars, brown dwarfs and young debris disks) are being observed.
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