List of example PhD projects
The following is a list of potential PhD projects that may start during 2019 within the Astronomy and Plasma Physics and Onsala Space Observatory Divisions within the Dept. of Space, Earth and Environment. Note, this is not necessarily a complete list of projects that may become available this year. At the same time, we do not necessarily expect to fill all of the positions, depending on research funding and other circumstances. Applicants should provide a rank ordered list of their preferences among the following projects, stopping at the point when you would no longer consider accepting a given topic. For example, if you would only consider projects 4 and 7 that relate to exoplanets, and prefer project 4, then your submitted list should be “4, 7”.
The project aims to study the dust-enshrouded rapid growth phases of galaxy nuclei - near and far. Specifically we investigate how supermassive black holes grow together with their host galaxies and the link to massive bursts of star formation (the Starburst-AGN connection"). We also study how the evolution of galaxies is regulated by feedback processes in the form of outflows, winds and jets powered by accreting supermassive black holes and/or star formation. This project involves observing and modelling high-resolution mm/subm observations acquired with e.g. ALMA (the Atacama Large Millimeter/submillimeter Array). The project also involves working with longer wavelength interferometric observations such as with LOFAR and VLA. The selected candidate will perform radiative transfer calculations and she/he will also utilize advanced data fitting techniques. To study the co-evolution between growing supermassive black holes and star formation, the candidate will also use models of stellar nucleosynthesis.
The project aims to use astrochemistry to probe the evolution of of starformation and the growth of supermassive black holes. Astrochemical techniques are emerging as an essential , and in some cases the only, diagnostic tool for identifying activity, tracing its evolutionary status and therefore establishing a proper understanding of how galaxies evolve and grow. In this project we have a specific focus in developing astrochemical techniques to identify hitherto undiscovered growing supermassive black holes. This project involves observing and modelling high-resolution mm/subm observations acquired with e.g. ALMA (the Atacama Large Millimeter/submillimeter Array) – for example through getting involved in our ALMA Large programme ALCHEMI. The project also involves working with longer wavelength interferometric observations such as with VLA. The selected candidate will perform astrochemical modeling and radiative transfer calculations and work closely with theorists.
The PhD project is on the topic of galaxy evolution and specifically about massive galaxies. By studying the galaxies and powerful active galactic nuclei (AGN) at high redshifts, it is possible to investigate the earlier phases that lead up to today's massive systems. Among the important questions are, what is the potential connection between star-formation and AGN activity as well as what is the role of the environment. The PhD research project will use radio and mm data from the facilities such as ALMA to focus on the gas and dust properties. The work will be performed in local and international collaboration.
The objective of this project is to address the enormous diversity among exoplanets and begin true comparative planetology in order to improve the understanding of the formation and evolution of planetary systems, and to assess the possibility of habitable planets outside the Solar system. The project will include testing and developing transit detection algorithms, search for planets in light curve analysis of transiting exoplanets using data from current (NASAs Kepler/K2 and TESS) and future (ESAs CHEOPS) spacecrafts, and the acquisition and interpretation of supporting, mainly spectroscopic, ground based data in order to characterise the detected exoplanets and their systems. The work is performed in collaboration with international teams with long records of publications.
Massive stars, i.e., those with more than 8 solar masses that explode as supernovae at the end of their lives, are important throughout astrophysics, yet many open questions remain about how they form (see, e.g., Tan et al. 2014, Protostars & Planets VI, p149, arXiv:1402.0919 or Tan 2018, IAUS 332, 139, arXiv:1710.11607). This formation may also be intimately connected to star cluster formation, which are environments where most stars, perhaps including the Sun, are born. This thesis project, part of the ERC Advanced Grant MSTAR - Massive Star Formation Through the Universe, has a broad scope of testing theories of massive star formation by using state-of-the-art observational data, especially from ALMA and SOFIA, but potentially also extending to many other facilities. Some theoretical modelling to help interpret the observational data is also within the scope of the project.
Massive stars, i.e., those with more than 8 solar masses that explode as supernovae at the end of their lives, are important throughout astrophysics, yet many open questions remain about how they form (see, e.g., Tan et al. 2014, Protostars & Planets VI, p149, arXiv:1402.0919 or Tan 2018, IAUS 332, 139, arXiv:1710.11607). This formation may also be intimately connected to star cluster formation, which are environments where most stars, perhaps including the Sun, are born. This thesis project, part of the ERC Advanced Grant MSTAR - Massive Star Formation Through the Universe, has a broad scope of developing theoretical models of massive star formation, for example using techniques of numerical simulations of magneto-hydrodynamics, astrochemistry and radiative transfer. The aim will be to make predictions that can be tested against latest observational data, including projects within the local research group.
Thousands of exoplanets have been discovered in the last decade, representing entirely new classes of planetary systems. In particular Systems with Tightly-packed Inner Planets (STIPs), consisting of multiple ~1 to 10 Earth-mass planets in close, inner orbits around their host stars, are now known to be extremely common: about 30-50% of all low-mass stars appear to harbour STIPs. A significant fraction of STIPs may contain habitable planetary environments. Thus understanding the formation of STIPs is one of the most important problems in astrophysics. This PhD project will focus on theoretical modelling of processes relevant to STIP formation. One class of models involves formation of these planets “in situ”, i.e., at locations similar to where we see the planets today. Another class of models involves “migration” of the planets to inner disk regions, having formed in the outer disk. One particular in situ model is Inside-Out Planet Formation (IOPF) (Chatterjee & Tan 2014, ApJ, 780, 53, Paper I; see also Mohanty et al. 2018, ApJ, 861, 144, Paper V, and references therein). It is anticipated that the PhD project will involve development of new aspects of IOPF theory, potentially including numerical simulation (dynamics of gas, dust and pebbles, radiative transfer, astrochemistry) of protoplanetary disks and the planet formation processes within them. Predictions that can be tested by current and future observations of protoplanetary disks, e.g., with ALMA, and exoplanet populations, e.g., with TESS, ARIEL, will also be important.
Evolved stars are responsible for interstellar enrichment, the return into the interstellar medium of elements and dust that are fundamental for the formation of stars, planets and life. ALMA now allows sensitive spectra line observations to determine how dust is formed and what the elemental abundances returned to the ISM are. This project will use existing and new line surveys of different types of evolved stars to determine the circumstellar chemistry on all scales. This will be compared with new chemical models that in particularly aim to treat the, now evident, very non-symmetric structures in the near stellar environment.