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We report on the detailed study of the 2008 October outburst from the anomalous X-ray pulsar 1E 5408 discovered through the Swift/Burst Alert Telescope (BAT) detection of soft gamma-ray repeater like short X-ray bursts on 2008 October 3. The Swift/X-ray Telescope (XRT) started observing the source after less than 100 s since the BAT trigger, when the flux ( in the 2-10 keV range) was >50 times higher than its quiescent level. Swift monitored the outbursting activity of 1E 5408 on a daily basis for approximately three weeks. This strategy allowed us to find a phase-coherent solution for the source pulsations after the burst, which, besides P and , requires a positive term (spin-down increase). The time evolution of the pulse shape is complex and variable, with the pulsed fraction increasing from 20 to 50 per cent within the Swift observational window. The XRT spectra can be fitted well by means of a single component, either a power law (PL) or a blackbody. During the very initial phases of the outburst the spectrum is hard, with a PL photon index (or ), which steepens to (or ) within one day from the BAT trigger, though the two components are likely present simultaneously during the first-day spectra. An INTEGRAL observation carried out five days after the trigger provided an upper limit of to the emission of 1E 5408 in the 18-60 keV band. [ABSTRACT FROM AUTHOR]

In 2008 May, the soft gamma-ray repeater (SGR) SGR 1627−41 resumed its bursting activity after nearly a decade of quiescence. After detection of a bright burst, Swift pointed its X-ray telescope in the direction of the source in less than five hours and followed it for over five weeks. In this Letter, we present an analysis of the data from these Swift observations and an XMM–Newton one performed when SGR 1627−41 was still in a quiescent state. The analysis of the bursts detected with Swift/Burst Alert Telescope shows that their temporal and spectral properties are similar to those found in previous observations of SGR 1627−41 and other SGRs. The maximum peak luminosity of the bursts was . Our data show that the outburst was accompanied by a fast flux enhancement and by a hardening of the spectrum with respect to the persistent emission. [ABSTRACT FROM AUTHOR]