Probing the star-forming ISM with fine structure lines

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) (https://www.cardiff.ac.uk/study/international/english-language-requirements) 

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 (https://www.cardiff.ac.uk/study/postgraduate/research/programmes/programme/physics-and-astronomy) 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. 

Cardiff University and the School of Physics and Astronomy are committed to supporting and promoting equality and diversity. Our inclusive environment welcomes applications from talented people from diverse backgrounds. We strongly welcome female applicants and those from any ethnic minority group, as they are underrepresented in our School. The School of Physics & Astronomy has a Juno Practitioner accreditation that recognises good employment practice and a commitment to develop the careers of women working in science. The University is committed to ensuring that we sustain a positive working environment for all staff to flourish and achieve. As part of this commitment, the University has developed a flexible and responsive framework of procedures to support staff in managing their work and personal commitments wherever possible. Applications are welcome from individuals who wish to work part-time or full time. 

Cardiff University is a signatory to the San Francisco Declaration on Research Assessment (DORA), which means that in hiring and promotion decisions we will evaluate applicants on the quality of their research, not publication metrics or the identity of the journal in which the research is published. More information is available at: Responsible research assessment - research – Cardiff University. 

Applications may be submitted in Welsh, and an application submitted in Welsh will not be treated less favourably than an application submitted in English.  We very much welcome applications in Welsh.