Descripción del proyecto
Una forma innovadora de observar galaxias
Los agujeros negros supermasivos situados en el centro de las galaxias y la materia oscura que se encuentra en los halos galácticos son partes esenciales de los procesos que impulsan la formación de las galaxias, incluida la nuestra. Sin embargo, la observación directa de nuestro centro galáctico (CG) y del halo presenta ciertos retos. El proyecto VEGA_P, financiado con fondos europeos, desarrollará un marco que permitirá observar tanto el CG como el halo mediante un enfoque revolucionario. Utilizará datos avanzados para observar las estrellas que interactúan con los agujeros negros y la materia oscura, lo que permitirá recoger información clave sobre ambos. Esto podría contribuir significativamente a la observación de las fuerzas motrices de las galaxias, lo que ofrecería nuevos conocimientos sobre su formación y los fenómenos galácticos que se producen en su interior.
Objetivo
Supermassive black holes — located in galactic nuclei— and dark matter —dominant in galactic halos— are vital ingredients in the cosmological process of galaxy formation, including that of our own Galaxy. However, probing our Galactic Centre (GC) and halo has proven observationally challenging. Hypervelocity stars (HVSs) are unique in that they deliver key information on both. Following interactions with black holes in the vicinity of Sagittarius A*, HVSs are ejected on fast trajectories through the halo. They thus bear testimony not only to the black hole and stellar populations within the hard-to-access innermost parsec, but also to the Galactic mass distribution, imprinted on their orbits.
Exploiting HVSs, however, has been limited by the paucity and quality of data. The ESA Gaia mission and new spectroscopic surveys are about to dramatically change this. Their upcoming data releases contain a few hundred HVSs with unprecedented astrometric measurements, but identifying them requires careful analysis of the basic data. This proposal capitalises on my comprehensive theoretical, observational and data mining work on SDSS and previous Gaia data.
The proposal unprecedentedly combines three key facets: i) identifying and characterising HVSs; ii) modelling HVS data in a full statistical framework and theoretically interpreting our results for the GC; and iii) performing a joint analysis with complementary Galactic halo probes, never observed so abundantly before Gaia.
The project will yield i) ~hundred of GC stars in a complementary mass range and with more robust parameter estimation than from direct GC observations; ii) the population of black holes in the GC and their dynamics; iii) robust ~10% precision measurements of the Galaxy mass distribution. These will allow not only to discriminate between assembly scenarios for both the Milky Way and its GC, but also to uniquely calibrate rate estimates for galactic nuclear phenomena, including gravitational wave sources.
Programa(s)
Régimen de financiación
ERC-COG - Consolidator GrantInstitución de acogida
2311 EZ Leiden
Países Bajos