Research Interests

My main research interests lie in observational methods to study turbulence in the diffuse interstellar medium and in supernova remnants and HII regions, and characterizing the strength and structure of the Galactic magnetic field.

Here I give some examples of current projects.

Southern Galactic Plane Survey

The Southern Galactic Plane Survey (SGPS) is a 1.4 GHz radiopolarimetric survey of a narrow strip around the Galactic plane in Galactic longitude range [253^o, 358^o]. Measurements of Faraday rotation and depolarization allow estimation of the electron-density-weighted magnetic field and scale of structure in the ionized interstellar medium. Furthermore, the unequalled resolution of the SGPS opens a new window for study of supernova remnants, HII regions and interstellar shock waves. Main collaborators on the SGPS are Bryan Gaensler (USyd), Naomi McClure-Griffiths (ATNF), John Dickey (UTas), and Anne Green (USyd).

Vela supernova remnant

SGPS radio synchrotron and polarization observations of a part of the vela supernova remnant, combined with optical and X-ray data will give a new handle to explore the composition of the remnants, its interaction with the surrounding medium, particle acceleration and interstellar shock waves. In collaboration with Paul Plucinksy (CfA), Bryan Gaensler (USyd), Douglas Bock (CARMA).

Parkes Galactic Meridian Survey

The Parkes Galactc Meridian Survey (PGMS) is a radiopolarimetric survey at 2.3 GHz that consists of a 5^o strip around a meridian at Galactic longitude 254^o, from Galactic latitude 0^o to -90^o. Science goals of the survey are two-fold: determining the position dependence of Galactic synchrotron radiation for future Cosmic Microwave Background Polarization experiments, and studying the Galactic magnetic field in the halo and disk-halo connection. Main collaborators are Ettore Carretti (IRA Bologna, PI), Dave McConnell (ATNF), Naomi McClure-Griffiths (ATNF), and Gianni Bernardi (ASTRON).

S-band Parkes All-Sky Survey

Successor survey for the PGMS: all southern-sky at 2.3 GHz, full polarization, and with absolute zero-level flux calibration.

Numerical simulation of the magnetized ISM

Magnetohydrodynamical modeling is a necessary complement to observations and analytical theory for gaining insight in the physical processes which play a role in the interstellar medium. With Fabian Heitsch (University of Michigan), we study the propagation of polarized radiation and its depolarization characteristics by comparing numerical models with radiopolarimetric observations.

Enigmatic Faraday rotation structure

Peter Katgert (Leiden) and Ger de Bruyn (ASTRON) discovered an intriguing high-latitude structure which is solely visible in low-frequency polarization. We have reobserved this structure in multiple frequencies to be able to study its magnetic field structure. Its regular depolarization features suggest differential Faraday rotation by a fairly homogeneous medium, and we are exploring its interaction with the surrounding medium.