Neutron stars are amongst the most fascinating and exotic objects in the Universe and I am interested in all manner of their phenomena.
My research however, focuses on neutron stars as radio pulsars. I am involved in a number of projects ranging from high-precision pulsar timing to prototype software development for next-generation radio telescopes.
I work with the European Space Agency on the Galileo GNSS mission. We are generating an Earth-independent timescale using data from 18 millisecond radio pulsars observed with the European Pulsar Timing Array (EPTA) as part of a wider effort to detect low frequency gravitational waves from supermassive black-hole binaries. My role is to prepare monthly datasets from the EPTA in order to generate Ensemble Pulsar Time (EPT) . This timescale is then used to steer a physical hydrogen maser clock located at ESA’s ESTEC facility . As part of my role I have developed a software pipeline to collect data from EPTA telescopes, compute the EPT clock signal and continuously monitor data quality.
I am also a member of the Square Kilometre Array (SKA) Science Data Processing team where I am developing prototype algorithms for the real-time monitoring of pulsar timing data. I’m particularly interested in the early detection of pulsar glitches for which I am implementing machine learning techniques that can alert astronomers to such events and automatically trigger follow-up observations. These techniques are currently being tested in the Jodrell Bank pulsar timing pipeline.
In neutron star science I am primarily interested in the variability of pulsars. In particular, timing and emission variations mediated by changes to the dynamic interiors and magnetic fields of pulsars. To date I have discovered and/or measured ~50 pulsar glitches including the largest ever glitch in the Crab pulsar.
I completed my Masters degree in Astrophysics at the University of York. My research there focused on the nuclear physics of accreting neutron stars. These are binary systems in which a neutron star strips material from the envelope of a close evolved companion star. Under the high temperature and pressure conditions of a neutron star surface the material undergoes nuclear burning, getting hotter and hotter, until it explodes as a Type I X-ray burst.
During these bursts, unstable proton rich nuclear species are formed in the rapid proton capture (rp- ) process. These decay on a range of timescales towards more stable species. Some species take a relatively long time to decay (e.g., Germanium-64, Selenium-68, Krypton-72) and so the abundances of these nuclei temporarily spike after a burst. These are known as waiting points and their decay rates are not well constrained. We investigated how sensitive the burst output is to the uncertainties in these decay rates and to the composition of the ashes from the previous burst.
- Delayed spin-ups of the Crab pulsar glitches as a core superfluidity phenomenon, Zheng. X, et al., (submitted)
- PulChron – A pulsar timescale demonstration for positioning, navigation and timing systems, Piriz. R, t al., Proceedings of the 50th Annual Precise Time and Time Interval Systems and Applications Meeting, 2019,
- Evolution of the low-frequency pulse profile of PSR B2217+47, Michilli. D, et al., 2018, Proceedings of the IAU 2018, Volume 13, pp291-294
- A glitch in the Crab pulsar (B0531+21). Shaw. B, et al., 2018 The Astronomer’s Telegram, #11625
- The largest glitch observed in the Crab pulsar. Shaw. B, et al., MNRAS, 2018, In press
- Correlated emission and spin-down variability in radio pulsars. Shaw. B, et al., Proceedings of the IAU, 2018, Volume 13, pp58-61
- Low-frequency pulse profile variation in PSR B2217+47: evidence for echoes from the interstellar medium. Michilli. D, et al., 2018, MNRAS, 476, 2704
- Resolving discrete pulsar spin-down states with current and future instrumentation. Shaw. B, et al., 2018 MNRAS, 475, 5443
- A large glitch in the Crab pulsar (B0531+21). Shaw. B, et al., 2017 The Astronomer’s Telegram, #10939
- The glitch activity of neutron stars. Fuentes, J.R et al., 2017, Astronomy And Astrophysics, 608, A131
- Probing the Milky Way. Asanok, K, et al., 2016, Astronomy and Geophysics, Volume 57, Issue 3, p.3.31-3.35
Science Possibilities Investigating Neutron Stars in the UK (SPINS-UK) – UCL, London, UK (2019)
Talk title: Time-resolved spin-ups in Crab pulsar glitches
European Pulsar Timing Array – Bielefeld, Germany (2018)
Talk title: PulChron – A pulsar timescale demonstration for Galileo
Science Possibilities Investigating Neutron Stars (SPINS) – University of East Anglia, UK (2018)
Talk title: The largest glitch in the Crab pulsar
PHAROS WG2 – Superfluids and superconductors in neutron stars – N. Copernicus Astronomical Center, Warsaw, Poland (2018)
Talk title: The largest glitch in the Crab pulsar
LGBT STEMinar – University of York (2018) – Contributing Speaker
Talk title: Pulsar timing and fundamental physics
Pulsar Astrophysics: The Next 50 years. Jodrell Bank (2017) – Contributing Speaker
Talk title: Correlated emission and spin-variability in pulsars
NewCompStar. Southampton, UK (2016) – Invited Speaker
Talk title: Resolving glitches in the Square Kilometre Array era
- European Pulsar Timing Array. Cagliari, Sardinia (2016)
- European Pulsar Timing Array. Orlean, France (2016)
- International Pulsar Timing Array. New South Wales, Australia (2015)
- European Pulsar Timing Array. Bonn, Germany (2015)
- IoP Radioactivity in Astrophysics Meeting. University of York (2014)
- Nucleosynthesis – Origins and Impacts. Royal Astronomical Society, London (2014)