[IPARCOS astro-seminar] Dec 15th 2023 @10:00 (CET) "Anisotropies in the Local Velocity Field of the Galactic disk and the Local Dark Matter Density"

[ENRICA BELLOCCHI]

Dr. Borja Anguiano

Anisotropies in the Local Velocity Field of the Galactic disk and the Local Dark Matter Density

In this talk I will revisit the determination of the vertical force and implied total mass density distribution of the Milky Way disk  for a wide range of Galactocentric radius and vertical height using chemically selected thin and thick disc samples based on Apache Point
Observatory Galactic Evolution Experiment spectroscopy combined with the Gaia astrometry. We derived the velocity dispersion profiles in Galactic cylindrical coordinates, and solved the Jeans equation for the two samples separately. The result is surprising that the total surface mass density as a function of vertical height as derived for these two chemically distinguished populations is different. The discrepancies are larger in the inner compared to the outer Galaxy, with the density calculated from thick disc being larger, independent of the Galactic radius. Furthermore, while there is an overall good agreement between the total mass density derived for the thick disc population and the standard halo model for vertical heights larger than 1 kpc, close to the mid-plane the mass density observed using the thick disc population is larger than that predicted from the standard halo model. I will also discuss future plans.

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The talk will take place both in person at Seminar Room 2 (Ground floor) of Facultad de CC. Físicas (UCM) and online (Zoom & Youtube live).

The Zoom link will be provided on Friday morning.

The IPARCOS astro-seminars in youtube: click here

Full list of the IPARCOS astro seminars and colloquia: here

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Enrica Bellocchi

Investigadora postdoctoral María Zambrano

Departamento de Física de la Tierra y Astrofísica & Instituto de Física de Partículas y del Cosmos
Facultad Ciencias Físicas

Universidad Complutense de Madrid

Plaza Ciencias, 1, E-28040 Madrid, Spain 

Phone: (+34) 91 394 4587

enri...@ucm.es

[ENRICA BELLOCCHI]

* Please note that the seminar will be broadcast today only via Zoom *

Dr. Borja Anguiano

Anisotropies in the Local Velocity Field of the Galactic disk and the Local Dark Matter Density

In this talk I will revisit the determination of the vertical force and implied total mass density distribution of the Milky Way disk  for a wide range of Galactocentric radius and vertical height using chemically selected thin and thick disc samples based on Apache Point Observatory Galactic Evolution Experiment spectroscopy combined with the Gaia astrometry. We derived the velocity dispersion profiles in Galactic cylindrical coordinates, and solved the Jeans equation for the two samples separately. The result is surprising that the total surface mass density as a function of vertical height as derived for these two chemically distinguished populations is different. The discrepancies are larger in the inner compared to the outer Galaxy, with the density calculated from thick disc being larger, independent of the Galactic radius. Furthermore, while there is an overall good agreement between the total mass density derived for the thick disc population and the standard halo model for vertical heights larger than 1 kpc, close to the mid-plane the mass density observed using the thick disc population is larger than that predicted from the standard halo model. I will also discuss future plans.

---

The talk will take place both in person at Seminar Room 2 (Ground floor) of Facultad de CC. Físicas (UCM) and online (ONLY Zoom).

The link to join the zoom is the following: https://rediris.zoom.us/j/84897143090

The IPARCOS astro-seminars in youtube: click here

Full list of the IPARCOS astro seminars and colloquia: here