The role of prestellar cores in star formation

Prestellar cores, the dense gravitationally bound objects out of which young stellar systems are born, mark the boundary between the ISM and the onset of the star formation process. Since these cores represent the ‘initial conditions’ for star formation, the study of their properties has become the focus of extensive observational surveys e.g. with Herschel, ALMA and IRAM.

However, interpreting the observational data can be extremely difficult — typically the observations yield information that is significantly beyond the predictive power of the previous/current generation of star formation simulations and models. As such, many questions as to the role that prestellar cores play in the overall star formation process remain either unanswered or hotly debated. In this project, the student will make the first comprehensive numerical study of the formation and evolution of prestellar cores that can start to address some of these issues.

The student will perform state-of-the-art numerical simulations (such as the one shown in the figure) that combine self-gravity, (magneto)hydrodynamics, time-dependent chemistry and ISM thermodynamics. These simulations will capture the formation of prestellar cores in molecular clouds. The simulations provide information about the dust in the cores and their surrounding, that will enable us to create ‘synthetic observations’ that we can use to compare simulation data to the current observational surveys. This will allow us build a picture of early stages of the star formation process, as would be seen by Herschel.

The project will address key open questions, such as 1) establishing how quickly these cores form and what physical processes govern their properties, 2) what role these cores play in setting the final mass of the stars that form within (i.e. are they responsible for the shape of the ‘initial mass function’), 3) whether we can unambiguously tell whether a core is ‘prestellar’ (i.e. one that will capable of forming a star), or simply a transient over-density, and 4) investigate if the core population in a molecular cloud can be used to determine the age of the star-forming region and the rate of star formation within.

Summary: The student will use computer simulations to model 1) the star formation process in molecular clouds, and 2) the light from these regions that can be seen by current ground and space based observatories. Over the course of the PhD, the student will have the opportunity to study a wide range of astrophysical processes, including fluid dynamics, physical chemistry, and radiative transfer. Code development will not be required for the project, although there is room for developing new physics in the model, should the student have an interest.

This project will be funded by the STFC.
Applicants should apply to the Doctor of Philosophy in Physics and Astronomy with a start date of 1st October 2020.
https://www.cardiff.ac.uk/study/postgraduate/research/programmes/programme/physics-and-astronomy

In the research proposal section of your application, please specify the project title and supervisors of this project. If you are applying for more than one project, please list the individual titles of the projects in the text box provided. In the funding section, please select ’I will be applying for a scholarship/grant’ and specify that you are applying for advertised funding from the STFC.

Applicants will need to submit the following documents with their application:
- post high school certificates and transcripts to date
- academic CV
- personal statement
- two academic references. Your references can either be uploaded with your application, or emailed by the referee to [Email Address Removed] or [Email Address Removed]