Magnetars: structure and evolution from p-star models

¹ Dipartimento Interateneo di Fisica, Università di Bari, via G. Amendola 173, 70126 Bari, Italy e-mail: Paolo.Cea@ba.infn.it
² INFN - Sezione di Bari, Via G. Amendola 173, 70126 Bari, Italy

Received: 20 June 2005
Accepted: 22 November 2005

Abstract

P-stars are compact stars made of up-and-down quarks in β-equilibrium with electrons in a chromomagnetic condensate. We discuss p-stars endowed with super strong dipolar magnetic field that, following consolidated tradition in literature, are referred to as magnetars. We show that soft gamma-ray repeaters and anomalous X-ray pulsars can be understood within our theory. We find a well-defined criterion to distinguish rotation-powered pulsars from magnetic-powered pulsars. We show that glitches, which in our magnetars are triggered by magnetic dissipative effects in the inner core, explain both the quiescent emission and bursts in soft gamma-ray repeaters and anomalous X-ray pulsars. We account for the braking glitch from SGR 1900+14 and the normal glitch from AXP 1E 2259+586 following a giant burst. We discuss and explain the observed anti correlation between hardness ratio and intensity. Within our magnetar theory we are able to quantitatively account for light curves for both gamma-ray repeaters and anomalous X-ray pulsars. In particular we explain the puzzling light curve after the June 18, 2002 giant burst from AXP 1E 2259+586.