Finding Pulsars in Radio Images
Mentor 1
David Kaplan
Mentor 2
Megan Jones
Start Date
16-4-2021 12:00 AM
Description
Pulsars are a type of compact star that emit a beam of radio waves. As they spin regular pulses of radio waves can be seen here on Earth. They are both rare and difficult to detect, but are very useful both as a testing ground for physics and in the search for gravitational waves. Typically pulsars are found by large radio dishes that scan the sky looking for repeated pulses. This means they might miss unusual pulsars whose pulses are smeared out, turn on and off, or are otherwise hard to find. In contrast, networks of radio telescopes called “interferometers” can make images of the radio sky and identify hundreds of thousands of objects, but are unable to figure out which are pulsing. In images of the radio sky, the vast majority of sources are not pulsars (only about 1 in 10,000). Identifying new pulsars is particularly tricky, as they are hard to distinguish from the other objects. However, pulsars have some unique characteristics that may allow us to pick them out: the polarization of the radiation. Radiation is emitted in waves, and polarization has to do with the angles of the waves as they travel through space. Pulsars tend to release circularly polarized radiation, which is very rare. This project involves looking through data from the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope in Australia to identify and measure the properties of known radio pulsars. This includes the brightness at different frequencies and how polarized they are. Looking at these properties for the population as a whole helps find new pulsars based on trends in the properties of known ones.
Finding Pulsars in Radio Images
Pulsars are a type of compact star that emit a beam of radio waves. As they spin regular pulses of radio waves can be seen here on Earth. They are both rare and difficult to detect, but are very useful both as a testing ground for physics and in the search for gravitational waves. Typically pulsars are found by large radio dishes that scan the sky looking for repeated pulses. This means they might miss unusual pulsars whose pulses are smeared out, turn on and off, or are otherwise hard to find. In contrast, networks of radio telescopes called “interferometers” can make images of the radio sky and identify hundreds of thousands of objects, but are unable to figure out which are pulsing. In images of the radio sky, the vast majority of sources are not pulsars (only about 1 in 10,000). Identifying new pulsars is particularly tricky, as they are hard to distinguish from the other objects. However, pulsars have some unique characteristics that may allow us to pick them out: the polarization of the radiation. Radiation is emitted in waves, and polarization has to do with the angles of the waves as they travel through space. Pulsars tend to release circularly polarized radiation, which is very rare. This project involves looking through data from the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope in Australia to identify and measure the properties of known radio pulsars. This includes the brightness at different frequencies and how polarized they are. Looking at these properties for the population as a whole helps find new pulsars based on trends in the properties of known ones.
