Soft Gamma-ray Repeaters and Anomolous X-ray Pulsars within the Quark-Nova Scenario

by Dr Brian Niebergal (Univ. Calgary)

Monday 25 Sept 2006, 10:15 → 11:00 Europe/Stockholm

In this talk I will present a new model for Soft Gamma-ray Repeaters (SGRs) and Anomalous X-ray Pulsars (AXPs) within the quark-nova scenario. If an isolated neutron star experiences a Quark Nova explosion/transition to a quark stars, an Iron-rich shell of degenerate matter forms out of the fall-back (crust) material. Our model can account for many of the observed features of SGRs and AXPs such as: (i) the two types of bursts (giant and regular); (ii) the spin-up and spin-down episodes during and following the bursts; (iii) the energetics of the boxing day burst, SGR1806+20; (iv) the presence of an Iron line as observed in SGR1900+14; (v) the correlation between the far-Infrared and the X-ray fluxes during the bursting episode and the quiescent phase; and (vi) the hard X-ray component observed in SGRs during the giant bursts. I will also discuss simulations of the alignment (with the rotation axis) of the quark's star magnetic field induced by the Meissner effect following the quark-nova. This can naturally explain why SGRs and AXPs do not show any pulsed radio-emission.