Implications of an anti-glitch in AXP/SGR

摘要

The recently observed anti-glitch of AXP 1E 2259+586 may be explained as the consequence of sudden accretion of retrograde matter. AXP/SGR are explained as single neutron stars accompanied by fallback matter from their natal supernov?, including rocky or metallic planetesimals. The upper bounds on a glitch or anti-glitch in the giant outburst of SGR 1806-20 pose a problem for any model.