Probing the star-forming ISM with fine structure lines

About the Project

Supersonic turbulent motions are thought to play a major role in the star formation process in galaxies. Theories have suggested that turbulence is responsible for shaping the interstellar medium (ISM), regulating star formation, and even setting the masses of stars as they form in young clusters. However, the properties of the turbulent motions in the ISM are difficult to determine: we can only use the doppler shifting of molecular emission lines to probe their velocities — giving us 1D, not 3D information — and these lines are often optically thick, such that their shapes are difficult to interpret. In addition, it is very difficult to observe many of these lines from ground, instead requiring satellite observatories with very cold, sensitive instruments – observatories which currently do not exist!

However, upcoming space observatories, such as NASA's proposed far infrared mission, will probe the spectral lines from species such as carbon and oxygen, to give astronomers a window on the temperatures, densities and dynamics of the star-forming gas in galaxies beyond the Milky Way. This project will pave the way for these future missions by constructing detailed computer models of the star forming ISM, which will be used to create synthetic observations of the spectral lines that form the focus of these space missions, and to fully examine what these lines can tell us about the star-forming gas in the ISM.

The student will use our state-of-the-art astrophysical fluid code to model the turbulent ISM under the wide variety of conditions that we expect in real galaxies. These computer models will involve (magneto)hydrodynamics, gravity, radiation/supernovae feedback from stars, cosmic rays, and time-dependant chemistry. The output from these simulations will then be used as input to radiative transfer codes, to produce synthetic observations of the interstellar medium, as it will be seen in the various lines probed by the up-coming space missions.

The work in this PhD will introduce the student to a wide range of ISM physics — such as ISM chemistry, molecular line radiative transfer, and fluid dynamics — and also advanced statistics and machine learning techniques.

For more information, or if there are any questions, please contact Professor Haley Gomez GomezH@cardiff.ac.uk

The typical academic requirement is a minimum of a 2:1 physics and astronomy or a relevant discipline.

Applicants whose first language is not English are normally expected to meet the minimum University requirements (e.g. IELTS 6.5 Overall with 5.5 minimum in sub-scores)

How to apply

Applicants should apply to the Doctor of Philosophy in Physics and Astronomy.

Applicants should submit an application for postgraduate study via the Cardiff University webpages including:

• your academic CV
• Your degree certificates and transcripts to date including certified translations if these are not in English
• a personal statement/covering letter
• two references, at least one of which should be academic. Your references can be emailed by the referee to physics-admissions@cardiff.ac.uk

Please note: We are do not contact referees directly for references for each applicant due to the volume of applications we receive.

In the "Research Proposal" section of your application, please specify the project title and supervisors of this project.

In the funding section, please select that you will be self-funded or include your own sponsorship or scholarship details.

Once your application is submitted, we will review it and advise you within a few weeks if you have been shortlisted for an interview.

Funding Notes

This project is offered for self-funded students only, or those with their own sponsorship or scholarship award.