Magnetic Field Effects on Pulsars

Grant Data
Project Title
Magnetic Field Effects on Pulsars
Principal Investigator
Dr Ng, Stephen Chi Yung   (Principal investigator)
Dr Takata Jumpei   (Co-Investigator)
Professor Cumming Andrew   (Co-Investigator)
Professor Kaspi Victoria M.   (Co-Investigator)
Dr Wang Zhongxiang   (Co-Investigator)
Start Date
Completion Date
Conference Title
Presentation Title
magnetic field, pulsars, magnetars, millisecond pulsars, radiation process
Others - Physical Sciences
Physical Sciences (P)
RGC General Research Fund (GRF)
HKU Project Code
Grant Type
General Research Fund (GRF)
Funding Year
2 Determining the physical conditions of magnetars and high-B RPPs from timing: the physical distinction between different pulsar classes could lie on the toroidal B-field component, which is not directly observable from spin down, but can give rise to complex pulse profiles. In order to test this theory, we will analyse the magnetars and high-B RPPs pulse profiles and quantify their complexity using a Fourier or wavelet technique. We will identify any correlations between the complexity and the surface temperature, field strength, and other physical parameters. Moreover, we will compile a database of magnetar glitches and carry out a statistical comparison with those of radio pulsars. The results will reveal effects of strong magnetic fields on pulsar interior structure. 3 Detecting magnetar emission at long wavelengths: four magnetars have radio pulsations detected, but the emission mechanism remains unclear. We propose new observations to measure the magnetar spectra at high radio frequency. This will fill in the gap between radio and infrared data and indicate any spectral turnover. The results will provide essential inputs for building a physical model. Also, detecting any correlated flux variabilities with emission at other wavelengths will localize the emission site to unveil the emission mechanism. 4 Measuring the hard X-ray spectra of MSPs: the strong magnetic fields at the light cylinders of MSPs result in short plasma instability timescales, which could lead to coherent radio emission in phase with gamma-ray pulsations. The radio waves would inverse-Compton scatter with energetic particles in the magnetosphere to produce X-rays. To test this idea, we propose new observations to measure the hard X-ray spectra of several MSPs. We will search for signatures of inverse-Compton emission. The results will make predictions to the low-frequency radio spectra, which can be tested with the on-going radio studies.