Understanding the extreme physics of pulsars with vast radio data sets
PhD projects beginning October 2026
Overview
A PhD position is an opportunity to direct your enthusiasm and creativity into ground-breaking research, with support to develop the skills you need to become a leader in your field. In this project, you will push the boundaries of our understanding of extreme neutron star physics, developing your own research ideas and building expertise in large-scale data science.
Project summary
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Pulsars, spinning neutron stars emitting a beam of radio waves, are some of the most extreme objects in the Universe, yet the physics of how they are powered remains a mystery. In this project, you will have access to over a million radio pulses from a thousand pulsars observed with MeerKAT, the most sensitive radio telescope in the Southern hemisphere. You will work with an international team of experts to investigate the physics driving pulsar radio emission. You will then apply pulsar physics to investigate the otherwise invisible structures of the Milky Way, and to make connections across the whole population of radio transients, from incredibly fast-spinning millisecond pulsars, to extragalactic Fast Radio Bursts.
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The MeerKAT telescope. Photo taken December 2017
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Scientific context
What are pulsars?
Pulsars are neutron stars: incredibly dense objects with mass just bigger than the Sun and radii of only 10 km. Radio pulsars emit a bright beam of radio waves that acts like the beam of a lighthouse, with the beam sweeping through space as neutron star spins. This means the radio emission appears to us on Earth as a series of pulses: one from each rotation of the star. We study these pulses across time, looking at the spin period and its variability; radio frequency; brightness; pulse shape; and polarization properties. These give us clues about the intense magnetic fields and plasma interactions taking place in the magnetosphere, revealing the origins of these stars and how they evolve over their lifetimes.
What do we learn from them?
Understanding the physics of pulsar radio emission is crucial for pushing the boundaries of modern physics. In addition to being some of the most extreme environments in the Universe, pulsars can be used as tools to probe fundamental physics and galactic structure. Pulsars spin so regularly that they can be used as clocks out in space. This means it is possible to test the theory of General Relativity and search for gravitational waves by timing the arrivals of pulses. The radio beam from a pulsar can be used as a torch that shines through and illuminates the invisible structures of the galaxy, that is, the gas, dust and plasma that make up the interstellar medium (ISM). By measuring the impact of the ISM on the radio emission we observe, we can even map out the magnetic field of the Milky Way. However, being able to use pulsars as precision tools in this way relies on our understanding how they work, and there are still many unanswered questions to address.
What problems do we need to solve?
Current models of pulsar physics are being pushed to breaking point by new discoveries. Examples include strange polarization behaviour, unexpected sudden changes, and unfathomably slow-spinning sources. On top of that, we know that pulsar timing (for finding gravitational waves) is limited by unexplained intrinsic variability in pulse arrivals. The bright flashes from other galaxies, known as Fast Radio Bursts (FRBs), may originate from a particularly extreme type of pulsar called a magnetar, but we do not yet understand the mechanisms relating ordinary pulsars to magnetars, and magnetars to FRBs.
How will this project address these problems?
We have collected a very large data set of pulsar observations with the Thousand-Pulsar-Array, a survey on the South African MeerKAT radio telescope. We know that the data set is full of variability, such as drifting, timing variability and profile changes, and it also contains unpredictable behaviour, such as mode-changing, and may even hold completely unexpected phenomena that we have not yet discovered. So far, we have barely scratched the surface of what such large-scale data can reveal about the connections and correlations in the physics of pulsar magnetospheres. By taking large scale statistical and data-centric approaches to pulsar science, we can advance our understanding of extreme and fundamental physics.
Pulsars are neutron stars: incredibly dense objects with mass just bigger than the Sun and radii of only 10 km. Radio pulsars emit a bright beam of radio waves that acts like the beam of a lighthouse, with the beam sweeping through space as neutron star spins. This means the radio emission appears to us on Earth as a series of pulses: one from each rotation of the star. We study these pulses across time, looking at the spin period and its variability; radio frequency; brightness; pulse shape; and polarization properties. These give us clues about the intense magnetic fields and plasma interactions taking place in the magnetosphere, revealing the origins of these stars and how they evolve over their lifetimes.
What do we learn from them?
Understanding the physics of pulsar radio emission is crucial for pushing the boundaries of modern physics. In addition to being some of the most extreme environments in the Universe, pulsars can be used as tools to probe fundamental physics and galactic structure. Pulsars spin so regularly that they can be used as clocks out in space. This means it is possible to test the theory of General Relativity and search for gravitational waves by timing the arrivals of pulses. The radio beam from a pulsar can be used as a torch that shines through and illuminates the invisible structures of the galaxy, that is, the gas, dust and plasma that make up the interstellar medium (ISM). By measuring the impact of the ISM on the radio emission we observe, we can even map out the magnetic field of the Milky Way. However, being able to use pulsars as precision tools in this way relies on our understanding how they work, and there are still many unanswered questions to address.
What problems do we need to solve?
Current models of pulsar physics are being pushed to breaking point by new discoveries. Examples include strange polarization behaviour, unexpected sudden changes, and unfathomably slow-spinning sources. On top of that, we know that pulsar timing (for finding gravitational waves) is limited by unexplained intrinsic variability in pulse arrivals. The bright flashes from other galaxies, known as Fast Radio Bursts (FRBs), may originate from a particularly extreme type of pulsar called a magnetar, but we do not yet understand the mechanisms relating ordinary pulsars to magnetars, and magnetars to FRBs.
How will this project address these problems?
We have collected a very large data set of pulsar observations with the Thousand-Pulsar-Array, a survey on the South African MeerKAT radio telescope. We know that the data set is full of variability, such as drifting, timing variability and profile changes, and it also contains unpredictable behaviour, such as mode-changing, and may even hold completely unexpected phenomena that we have not yet discovered. So far, we have barely scratched the surface of what such large-scale data can reveal about the connections and correlations in the physics of pulsar magnetospheres. By taking large scale statistical and data-centric approaches to pulsar science, we can advance our understanding of extreme and fundamental physics.
What skills will you develop?
Completing a PhD is a chance to fully immerse yourself in academic research and spend focused time answering the questions that you find the most exciting and important. It is also a fantastic opportunity to develop your skills in communicating ideas, managing projects, and interacting with a global research community. You will develop a wide array of key technical skills, including developing software; programming in Python; statistical techniques; and a strong grounding in data science and machine-learning.
What opportunities and support can you expect?
- The opportunity to take ownership of your own research and become a leader of projects and publications.
- A schedule of weekly supervisor meetings to help guide your development.
- Membership of international collaborations with two of the world’s best radio telescopes: Murriyang and MeerKAT.
- The chance to work with experts from across the world, particularly the UK, Germany, South Africa and Australia.
- A network of mentors both within pulsar science and at the University of Cambridge.
- Training: in data science and machine-learning; in Python programming and software development; in managing very large data sets; and in key communication skills.
- Opportunities to present your research at national and international conferences.
- A collaborative research trip to Australia.
How to apply
Full details of eligibility requirements, funding and how to apply are available on the Cambridge Astrophysics webpage: www.astro.phy.cam.ac.uk/gradresearch
Get in touch by email if you have any questions!
Get in touch by email if you have any questions!
