Ms Kathleen Sellick received her MSc summa cum laude for her research on the strong gravity effects on the electromagnetic field of a radio pulsar magnetosphere.
After matriculating with top honours from St Mary’s Diocesan School for Girls in Kloof, Sellick and her mother’s enquiries revealed that UKZN is a leading research facility in the field of astronomy. She was awarded a prestigious Square Kilometre Array (SKA) bursary and enrolled for a BSc. Her honours degree was co-funded by the SKA and the National Astrophysics and Space Science Programme (NASSP) and her master’s degree by the latter.
Sellick master’s study, which was supervised by Professor Subharthi Ray of the School of Mathematics, Statistics and Computer Science, sought to solve Maxwell’s equations in a strong magnetic and gravitational field.
‘Neutron stars host a very strong magnetic field and spin with periods of a few seconds to as high as milliseconds,’ said Sellick. ‘The general relativistic effects of a neutron star also play a substantial role in the physics at the stellar surface. In order to account for the motion of charged particles in the magnetosphere immediately outside the stellar surface, it is essential to include the general relativistic effects in the Maxwell’s equations.
‘We used a 3+1 decomposition of the spacetime to account for the frame dragging effects due to the stellar spin. This was used alongside vector spherical harmonics in a curved spacetime, to find solutions to Maxwell’s equations of an isolated neutron star in a vacuum for an aligned and orthogonal dipole magnetic field.’
Sellick explained that in a realistic scenario for a radio pulsar, the radio beams which originate from the pole caps of the magnetic field, have a finite angle with the spin axis and it is hence necessary to find a model for an oblique rotator.
‘It has been a lot of hard work, as to be expected, but well worth the time and effort. I had a great support team and people guiding me the whole way. I look forward to the work and discoveries to come.’
Ray said: ‘Kathleen is a very intelligent student who is very motivated to pursue her research career in Theoretical Astrophysics. She is also very enthusiastic about her research and keen to understand the fundamental physics behind the Astrophysical compact objects – the neutron stars, which have been a mystery for more than five decades. This research field is extremely challenging as it requires not only in-depth knowledge of Physics in order to formulate a mathematical model of the neutron star magnetosphere and the motion of particles there-in, but also a keen mathematical ability to solve them. I see her as a budding young scientist who will pursue a career in Theoretical Astrophysics.’
Sellick is currently enrolled for a PhD, focusing her research on pulsars and the emission mechanism of radio pulsars. She sees herself pursing postdoctoral studies and continuing her research in Theoretical Astrophysics to become a professional scientist in the field.
In her spare time, she rides horses, competes in show jumping and breeds competition horses. She also cares for rescue animals at her family-owned NPC animal sanctuary: The African Sanctuary.
Mrs Janice Sellick thanked UKZN, particularly Ray for supporting her daughter’s studies. ‘Kathleen is a disciplined student who manages to cope with the workload despite her active, animal-oriented lifestyle,’ she said.
Words: Leena Rajpal
Photograph: Abhi Indrarajan