Sep 5 – 7, 2023
Institute of Cosmos Sciences (ICCUB-IEEC)
Europe/Madrid timezone

Gaia DR3 determination of the Galactic bar pattern speed

Sep 6, 2023, 5:10 PM
15m

Speaker

Merce Romero-Gomez

Description

New 3D kinematic maps are derived based on Gaia DR3 proper motions and line-of-sight velocities for red giant branch stars, but now, unlike those published in Gaia Collaboration, Drimmel, Romero-Gómez+2022, taking into account the correlations between the proper motions, which contribute to the correlations between the derived kinematic variables. The large-scale correlations between the planar and vertical motions are studied, highlighting the impact of the bar and spiral perturbations on the stellar dynamics. Additionally, and taking advantage of the homogeneity of Gaia DR3 data, these maps are used to apply the recent version of the Tremaine-Weinberg method to compute the pattern speed of the Galactic bar (Bovy+2019, Leung+2021). The robustness and possible systematics of the method are tested using a set of test particle simulations of different bar pattern speeds and taking into account the expected observational errors. The value recovered using the Tremaine-Weinberg method is compatible with the one found in the Gaia Collaboration paper and previous works.

Primary authors

Merce Romero-Gomez Laurent Chemin (Instituto de Astrofísica, Universidad Andres Bello, Chile) Jason Hunt (Center for Computational Astrophysics, Flatiron Institute, New York, United States) Ron Drimmel (INAF - Osservatorio Astrofisico di Torino, Torino, Italy) Shourya Khanna (INAF - Osservatorio Astrofisico di Torino, Torino, Italy) Eloisa Poggio (Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Nice, France) Pau Ramos (National Astronomical Observatory of Japan, Tokyo, Japan)

Presentation materials