|
|
|
|
AMIGA (Analysis of the interstellar Medium of Isolated GAlaxies) is an interdisciplinary team at the Instituto de Astrofísica de Andalucía playing a major role in the SKA international project, a next generation radio telescope which will be the largest scientific infrastructure on Earth, and output data at a rate comparable to the entire present day bandwidth of the internet. The PI of this position coordinates the Spanish participation in the SKA, while her AMIGA team is strongly involved in preparatory science and in developing a Precursor SKA Regional Centre (SRC), an environment to provide access and resources to exploit data from SKA and its precursors. She has mentored a total of 6 PhD theses, 17 postdocs and 7 other staff. Thus, AMIGA provides an exceptional opportunity, unique in Spain, for a PhD candidate to become deeply involved in SKA, a facility that will be transformational for radio astronomy over the coming decades.
The proposed project falls into the core of AMIGA science, which focuses on comparing the properties of galaxies in extreme environments, with a special emphasis on atomic gas (HI) as a tracer of interactions, in which AMIGA has a unique expertise in Spain. The main AMIGA sample consists of about 700 highly isolated galaxies in the nearby Universe, acting as a reference for how galaxies evolve in the absence of external influences. A fundamental, but little studied, property in regulating the gas content and star formation in galaxies is their angular momentum (e.g. Obreschkow+2016, Lutz+ 2018). It may act as a hidden variable in scaling relations between optical properties (e.g. diameter or luminosity) and HI mass, and could potentially explain why such relations have considerable scatter. In the existing studies there are almost no isolated galaxies by the strict AMIGA criteria, hence an in-depth study of the angular momenta of isolated galaxies is crucially missing, and this constitutes the research context of the proposed PhD work.
The proposed PhD project aims to define the role of angular momentum in regulating the HI content of isolated galaxies, and so in galaxy evolution (fully aligned with SKA Prioritized Goals). In order to answer this question, the applicant will use existing radiointerferometric observations with SKA pathfinders, the VLA (Very Large Array) and GMRT (Giant Metrewave Radio Telescope), from the AMIGA database.
In collaboration with experts within the AMIGA team the candidate will:
• Reduce the VLA and GMRT data using the latest software and algorithms, within the framework of IAA SRC precursor activities.
• Model the kinematics of the galaxies using both 2D and 3D modelling software (e.g. GUIpsy, TiRiFiC and 3D Barolo). The resulting models will be compared using 3D visualisation tools such as SlicerAstro and X3D.
• Calculate the total angular momentum together with the stellar masses using optical and infrared data from both AMIGA’s own observations and ancillary data from other surveys.
• Once the total angular momentum has been calculated the global stability of the galaxies will be contrasted with the expected theoretical relation. Any deviations from this relation must then be investigated to understand both their cause and influence on the subsequent evolution of the galaxies.
There will also be highly beneficial opportunities for the candidate to expand the sample by leading proposals as PI. Even if this sample covers an adequate parameter space for the proposed study, it would benefit of obtaining additional HI observations with the recently upgraded GMRT to better cover lower mass galaxies. S/he would collaborate with teams in other SKA member countries, such as South Africa, Australia or the Netherlands, with which AMIGA has established collaborations. In addition, s/he will work following Open Science principles, an area in which AMIGA team plays a key role at an international level and an area that is increasingly recognized as essential in scientific careers.
IAA is an equal opportunity institution. Applications to this program by female scientists are particularly encouraged.
Should you need any further information or assistance concerning the application, please contact the IAA at severoochoa[at]iaa.es