Highlights


Selected highlights from my publications

Press releases / notes


2013/11: Direct formation of millisecond pulsars from rotationally delayed accretion-induced collapse of massive white dwarfs
(MNRAS Letters paper)
2013/12: Max Planck Institute for Radio Astronomy press release

See Sky and Telescope story on this.

2013/10: On the disruption of pulsar and X-ray binaries in globular clusters
(A&A paper)
Note: This paper presents a new characteristic dynamical parameter of globular clusters, the encounter rate per binary. This parameter goes a long way towards explaining the differences in the characteristics of the pulsar populations of different globular clusters. It also suggests that young pulsars in globular clusters are the results of the disruption of accreting X-ray binaries.

2013/09: Swings between rotation and accretion power in a binary millisecond pulsar
(Nature Paper)
2013/09: ESA press release
NASA press release

2013/08: A radio magnetar orbiting the supermassive black hole at the centre of the Galaxy
(Nature Paper)
2013/08: Max Planck Institute for Radio Astronomy press release
Max Planck Society press release

2013/04: A super-massive neutron star in a relativistic orbit!
Testing general relativity in a whole new territory!
(Science Paper)
2013/04: Max Planck Institute for Radio Astronomy press release
Max Planck Society press release
Bonn University press release
European Southern Observatory press release
Arecibo Observatory press release
National Radio Astronomy Observatory press release
European Research Council press release

2012/08: A new, ever-improving test of general relativity
(Classical and Quantum Gravity paper)
Note: Invited review in Classical and Quantum Gravity's Focus Issue on the Weak Equivalence Principle. It describes a new, superior method for testing the strong equivalence principle with binary pulsars.

2012/05: The measurement of the mass of PSR J1738+0333 and its companion allows the most stringent test of scalar-tensor theories of gravity
(MNRAS papers A and B).
Note: Sequence of two papers published back to back. These introduce very stringent constraints on scalar-tensor theories of gravity and show how we might soon exclude a wide family of tensor-vector-scalar theories of gravity that have been proposed as relativistic formulations of modified Newtonian dynamics.

See Sky and Telescope story on this and other GR tests.

2012/02: The most precise mass ever measured for a millisecond pulsar
(Astrophysical Journal paper)

2011/11: First γ-ray pulsar in a globular cluster
(Science Paper)
2011/11: Max Planck Institute for Radio Astronomy press release
Max Planck Society press release
NASA press release

2011/11: Discovery of Nine Gamma-Ray Pulsars in Fermi-LAT Data Using a New Blind Search Method
(Astrophysical Journal Paper)
2011/11: Max Planck Institute for Radio Astronomy press release
Max Planck Institute for Gravitational Physics press release
Max Planck Society press release
NASA press release

2011/06: Project BEACON funded

2010/11: On the nature and evolution of the binary pulsar J1903+0327
(MNRAS paper)
Note: In this paper we find that this eccentric MSP has a 1.03 M main sequence companion. The mass of the MSP is 1.667 ± 0.021 M (99.7% confidence limit). Finally, is shows the system started its evolution as a triple system.

2010/11: The orthometric parameterisation of the Shapiro delay and an improved test of general relativity with binary pulsars
(MNRAS paper)
Note: This paper describes a Fourier decomposition of the propagational delays observed in the timing of binary pulsars. It allows a proper understanding of the constraints on companion mass and orbital inclination derived from the detection of the Shapiro delay. This results in improved mass estimation and possibly tests of general relativity if other post-Keplerian parameters are measured for the same pulsar binary.

2011/04: Binary Pulsar Discovery by Global Volunteer Computing
(Astrophysical Journal paper)
2011/04: Max Planck Institute for Gravitational Physics press release

2010/09: Pulsar Discovery by Global Volunteer Computing
(Science Paper)
2010/08: Max Planck Institute for Gravitational Physics press release

2010/04: The First Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
(Astrophysical Journal Supplement Paper)
Note: This paper lists the 46 gamma-ray pulsars known at the time of publication. This is really major progress compared to the six known before the launch of the Fermi satellite!

2010/02: Faintest radio pulsar ever!
(Astrophysical Journal Paper)
Note: This paper is a great example of why the Fermi satellite is so awesome. At the highest energies (TeV), one of the brightest sources in the sky is MGRO J1908+06. The nature of this source was mysterious until Fermi discovered a bright, powerful gamma-ray pulsar near it, PSR J1907+0602 - indicating that MGRO J1908+06 is a pulsar wind nebula. Then a 1-hour observation with Arecibo detects this pulsar at radio wavelengths: it is one of the faintest radio pulsars ever detected. It would have never been found in regular radio pulsar surveys.

2009/07: A Population of Gamma-Ray Millisecond Pulsars Seen with the Fermi Large Area Telescope
(Science Paper)
2009/07: NASA's press release.

2009/02: A new technique for timing the double pulsar system
(MNRAS paper, in print 2009 July)
Note: This paper describes a technique that has the potential to improve the measurement of the mass ratio in the double pulsar, and possibly improve the precision of tests of general relativity with that system.

2008/05: An eccentric binary millisecond pulsar in the Galactic plane
(Science paper)
2008/05: Cornell University Press Release
NRAO Press Release

2007/12: A massive neutron star in the globular cluster M5
(Astrophysical Journal Paper, in print 2008 June 1)
2008/01: Cornell University Press Release

2007/11: A 2.7-solar mass neutron star???
(Astrophysical Journal Paper, in print 2008 March 1)
2008/01: Sky & Telescope article on last two massive neutron star discoveries.

2007/07: Arecibo finds a dozen new millisecond pulsars
(Astrophysical Journal paper)
2006/12: Arecibo Astronomy Highlight

2006/09: Most precise strong-field tests of general relativity ever
(Science paper)
2006/09: CSIRO press release.
Jodrell Bank Observatory press release.

2006/01: Fastest spinning pulsar ever
(Science paper)
2006/01: NRAO press release.

2005/11: The youngest binary pulsar ever found: the highly relativistic binary PSR J1906+0746
(Astrophysical Journal paper)
2006/01: Jodrell Bank Observatory press release
Arecibo Astronomy Highlight

2005/01: 21 new millisecond pulsars in Terzan 5
(Science paper)
2005/01: NRAO press release.

2004/03: Discovered most eccentric binary pulsar ever
(Astrophysical Journal paper)
2005/01: New Scientist publishes a story on some of the recent results of the GMRT, including the discovery of NGC 1851A.

2004/01: First double pulsar
(Science paper)
2004/01: Jodrell Bank Observatory press release.
CSIRO press release.

2001/10: Science publishes a story on the discovery of gas in 47 Tucanae.
2001/08: Detection of ionized gas in 47 Tucanae
(Astrophysical Journal paper)
2001/08: Jodrell Bank Observatory press release.

2001/09: Twelve new timing solutions in 47 Tucanae
(MNRAS paper)
Note: See why this is a cool result here.

2001/04: New method for estimating binary orbits
(MNRAS paper)
Note: This paper describes a new method that allows the determination of very sparsely sampled pulsar orbits. See idea (and ERRATUM) here.

2000/06: Nine new millisecond pulsars in 47 Tucanae
(Astrophysical Journal paper)
Note: See why this is a cool result here.