Joint Astrophysics Colloquium

Joint Astrophysics Seminar

Magnetars: New Puzzles

Chris Thompson

CITA

There is substantial evidence for a type of neutron star containing ultrastrong 10¹⁵ - 10¹⁶ G magnetic fields. These objects have been observed doing a number of dramatic things that are unheard of for ordinary radio pulsars. They are best known for their giant gamma-ray flares, whose energies can exceed 10⁴⁶ ergs, but also are observed as persistent sources of X-rays and gamma-rays, emitting up to 10,000 times more energy in 100 keV photons than is lost due to spindown. Compared with radio pulsars, the spindown of magnetars is rapid but also highly variable even in the absence of mass accretion. They are also prodigous sources of optical and IR radiation, and one magnetar has been detected as a pulsing radio source. This talk will summarize our current understanding of the physical properties of magnetars: how the magnetic field decays, their electrodynamic properties, the source of their non-thermal radiation, their superfluid properties, and their similarities and differences with strongly magnetic radio pulsars and other astrophysical beasts such as gamma-ray bursters.