Schematic figure showing the three phases of high-energy emission following magnetar giant flares, as observed in the 2004 event from SGR 1806–20. After the prompt ≲1 s gamma-ray spike, and the minutes-long pulsating X-ray tail modulated on the neutron star rotation period, a third emission phase was observed in the form a smoothly evolving MeV component (S. Mereghetti et al. 2005; S. E. Boggs et al. 2007; D. D. Frederiks et al. 2007). This delayed MeV emission rose to a peak luminosity over t ≈ 600–800 s, thereafter decaying smoothly until fading below the instrumental background a few hours later (see Appendix A and the bottom panel of Figure 2). The mechanism of baryon ejection shown in panel (a) is uncertain, but shock heating of the neutron star crust by energy released during magnetic reconnection is one possibility (C24) which would naturally lead to both a spin modulated X-ray tail and, as we argue here, delayed gamma rays from the freshly synthesized radioactive r-process material. We have illustrated the ejection as equatorial, but the direction of the mass ejection relative to the magnetic and spin axes is uncertain.