SGRs and AXPs: Evidence for Delayed Amplification of Magnetic Field after Neutron Star Formation?
Figure 2
(a) shows the cumulative age distribution for SNRs associated with AXPs and SGRs (diamonds and dot-dashed line). The solid line is the expected distribution for constant birth rate of 1/(1700 years). The triangles indicate the upper and lower SNR age limits corresponding roughly to limits. (b) shows the cumulative age distribution for AXPs/SGRs (circles and dashed line). The solid line is the expected distribution for constant birth rate of 1/(500 years). The diamonds and dotted line are the cumulative distribution for associated SNRs (from (a) scaled up by a factor of 3. To better illustrate this scaling, the 1/(1700 years) line is replotted (dot-dashed line). Systematic errors in spin-down age would shift the -axis and are in Section 2.1.
