Laboratoire d’Études du Rayonnement et de la Matière en Astrophysique et Atmosphères

Accueil > en > Intranet > HCERES evaluation

Autoevaluation document

par Darek Lis - publié le

Vague D
Campagne d’évaluation 2017 – 2018
Unité de recherche
Dossier d’autoévaluation

HCERES Document

Séminaires à venir

Mercredi 16 mai 2018, 11h00
Salle de l'atelier, Paris
Jour exceptionnel et heure exceptionnelle
Unveiling the Cosmic Dawn with the 21 cm signal
Vendredi 25 mai 2018, 14h00
Bâtiment B (Salle RdC proche cantine), Paris
Closing the gap between simulations and observations
résumé :
In this talk I will give an overview over my latest results to compare
current observations with latest 3D radiation MHD simulations of turbulent
protoplanetary disks. I will focus on the dust thermal emission in
protoplanetary disks, covering the outer regions which emit in the sub/mm.

In the talk I will present comparisons between the expected dust scale
height from simulations and observations
and how we could use this results to learn about the gas disk dynamics.
I will also show the possibility to explain mm polarization by dust grains
which are aligned by the magnetic field.

Finally I will draw conclusion on the results and discuss about the
possibility to observe MRI activity with current telescope facilities.
Vendredi 1 juin 2018, 14h00
Salle de l'atelier, Paris
Structures in protoplanetary disks: what do they tell us about planet formation ?
résumé :

Lundi 4 juin 2018, 14h00
Salle de l'atelier, Paris
Jour de la semaine exceptionnel
Inefficient jet-induced star formation in Centaurus A: High resolution ALMA observations of the northern filaments
Quentin SALOME
UNAM, Mexico
résumé :
Star formation is one of the key mechanisms driving the evolution of galaxies across cosmic times. The physical properties and the multi-scale dynamics of the molecular gas influence the star formation efficiency. The environment certainly also plays a role in star formation. In particular, recent studies suggest that AGN can regulate the gas accretion and thus slow down star formation. However, evidence of AGN positive feedback is also invoked in a few radio galaxies.

I will present different studies of the northern filaments of Centaurus A at different resolutions. These filaments extend on scales up to 15 kpc, aligned with the radio-jet, and show evidence of recent star formation (Rejkuba et al. 2001). They are the perfect testbed region for positive feedback, here through jet-induced star formation.

At the intersection of the radio jet and one of the HI shells that surround the galaxy (Schiminovich et al. 1994), CO emission in the shell has been detected with SEST (Charmandaris et al. 2000). With APEX, we mapped the CO emission along the FUV filaments that lie at the jet-HI interaction. In particular, we discovered a large amount of molecular gas outside the HI gas (Salomé et al. 2016). However, while the molecular gas reservoir is important, it is very inefficient to form stars compared to star-forming disc galaxies. To understand why star formation is inefficient, we obtained ALMA observations to map the CO emission along the filaments, at a resolution of ~20 pc (Salomé et al. 2017). Such resolution enabled us to separate giant molecular clouds and study their physical properties (mass, size, velocity dispersion).
Vendredi 8 juin 2018, 14h00
Salle de l'atelier, Paris
University of Michgan
Tous les séminaires...