A star is born: Aberdeen student is new supernova in international astrophysics

Twenty-two year old student James McLeman is seeing his future quite literally in the stars.

Weeks after graduating from the University of Aberdeen with a first-class degree in physics, the gifted student from Aberdeen finds himself already in orbit, as his theory on the birth of stars is published in the International Astrophysical Journal.

The theory put forward by James came about as a result of his being awarded in summer 2011 the Robert Cormack Summer Vacation Research Scholarships in astronomy from the Royal Society of Edinburgh. While fellow students spent that summer flipping burgers and serving pints, James was working on a mathematically-complex theoretical investigation of an event that underpins the sustainability of the universe itself – how stars can form from clouds of cold dense filaments drifting across space.

James’s supervisor and co-author Dr Charles Wang describes his student’s work as a fantastic achievement, saying: “James completed this work months before he finished the final year of his degree. To publish as an undergraduate is unthinkable, especially in what is regarded as the leading journal in this field.

“James was inspired by the excitement of how stars form in deepest space,” continues Dr Wang. “His outstanding academic record had prepared him well for the challenge which the Cormack Scholarship presented him with, and the result is an exciting piece of original theoretical astrophysics of the quality and significance which well deserves the achievement of publication in this leading journal.”

Charles Wang hit the headlines himself this summer with his work on one of the greatest mysteries of the universe – the end of a star’s life, and why and how single stars can explode and collapse. Dr Wang proposes the existence of a new type of particle – similar to the Higgs boson – and his work will be tested at CERN, the European Organization for Nuclear Research, in December.

James’s theory addresses the mysterious process by which cold dark clouds of intergalactic filaments can come together to form new stars. He was able to pinpoint and test the key conditions necessary for this to happen, using data recently collected from the space telescope Herschel which detects infra-red signals emitted by these clouds and travelling vast distances through space.

An insatiable thirst for knowledge from a young age led James down his chosen academic path. He said: "I have always been the kind of person who wants to understand the details of how things work and why. Studying physics at secondary school level convinced me that I wanted to continue academic studies in the subject.

“Understanding the formation of stars and their evolution has captivated human imagination since we first gazed up into the night sky. Despite vast progress in our quest to explain this phenomenon, gaps in our knowledge remain – we need additional theories to fully realise the complexity of stellar evolution.

“My project focused on tackling the questions arising during the early years of star formation, from their beginnings as a cloud of diffuse, cold plasma. At this temperature, the radiation emitted is not visible to standard optical telescopes, and so infrared telescopes such as Herschel Space Observatory are required to see into the darkness and observe these beautiful structures.

“The precise mechanism by which these infra-red dark clouds collapse - triggering the formation of protostars - is the subject of fierce debate. However, our paper provides a simple analytical approach to understanding the conditions required to trigger the collapse of cylindrical dark filamentary clouds.

“In collaboration with my supervisor  Dr Charles Wang and Professor Robert Bingham at the Rutherford Appleton Laboratory, I considered the effects of axial and azimuthal magnetic fields on the clouds. These two magnetic fields compete by performing two vitally different roles. The axial magnetic field tries to stabilise the dark filamentary cloud, preventing self gravitational collapse. On the other hand the azimuthal magnetic field seeks to destabilise the system, driving it towards instability and self-gravitational collapse.

“We showed that for sufficiently large and yet astronomically realistic currents, the azimuthal magnetic field can cause filamentary clouds to undergo instability resulting in their collapse. As it collapses the gravitational potential energy is converted into heat – and the result is the early stages of the formation of a protostar.

 “Working with Dr  Wang on this project and into my PhD has given me a great intuition about the world of academia, I couldn't have asked for a more insightful and knowledgeable supervisor.”

James has now embarked on a PhD at the University which is being funded through a prestigious Scottish Universities Physics Alliance Prize Studentship.  He continues: "My PhD will be looking at developing tools to measure the nature of gravity more precisely, which would allow us to better understand why certain astrophysical processes - such as star formations - occur. I'm hoping to build links with the European Space Agency as part of my research. In ten years time it would be amazing to say that I'd played a part in helping us better understand some of the great mysteries of the universe.

“The beauty of astrophysics continues to inspire me to tackle the big problems in physics - knowing that whatever we learn about the universe will mean we are one step closer to understanding our own world and are developing technologies to take us deeper into the unknowns of the cosmos.”