Magnetars are very exotic objects that are related to neutron stars and pulsars. A neutron star is formed when a massive star undergoes a supernova explosion. The super-dense core that is left after such an explosion is a neutron star. It is approximately 10 miles in diameter, yet weighs more than our Sun. We can observe some of those neutron stars as pulsars. Pulsars are highly magnetic, fast spinning neutron stars that emit beams of radio waves from their magnetic poles. Their high magnetic field and spin period are due to the conservation of magnetic flux and momentum during formation. Pulsar spin periods range from 1ms-8s and tend to slow down rapidly. That is another indication of a strong magnetic field, as magnetic braking causes the pulsar to spin-down rapidly. Magnetars are a type of a neutron star with extremely high magnetic fields of 1015-1014 G, which makes these stars the most magnetic objects known. These fields are thought to be generated by a dynamo action during the magnetar’s formation (Duncan and Thompson 1992). This is known as a magnetar model. The decay of the magnetic field creates powerful X-ray or gamma-ray emission. However, this magnetic field decays rather fast which makes the magnetar’s detectable lifespan short. Some of the known magnetars have poorly understood radio emission. Our group was motivated to better study the correlation between X-ray and radio activity of magnetars via a radio monitoring project. We are regularly observing eight magnetar sources that are visible with the 100-m Green Bank Telescope (GBT) located in Green Bank, WV. Our program is the first major effort to monitor these sources on a regular basis and complements other existing observing programs of southern objects at the Parkes radio telescope (Burgay et al. 2009; Camilo et al. 2009) as well as the high-energy monitoring projects with the Swift gamma-ray observatory and XMM X-ray observatory.
Edel, Stanislav; Ludovici, Dominic; Kondratiev, Vlad; Ridley, Joshua; and Boyles, Jason
"GBT Radio Monitoring of Magnetars,"
Mountaineer Undergraduate Research Review: Vol. 1
, Article 6.
Available at: https://researchrepository.wvu.edu/murr/vol1/iss1/6