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We report on new X‐ray outbursts observed with  Swift  from three Supergiant Fast X‐ray Transients (SFXTs): XTE J1739−302, IGR J17544−2619 and IGR J08408−4503. XTE J1739−302 underwent a new outburst on 2008 August 13, IGR J17544−2619 on 2008 September 4 and IGR J08408−4503 on 2008 September 21. While the XTE J1739−302 and IGR J08408−4503 bright emission triggered the  Swift /Burst Alert Telescope, IGR J17544−2619 did not, thus we could perform a spectral investigation only of the spectrum below 10 keV. The broad‐band spectra from XTE J1739−302 and IGR J08408−4503 were compatible with the X‐ray spectral shape displayed during the previous flares. A variable absorbing column density during the flare was observed in XTE J1739−302 for the first time. The broad‐band spectrum of IGR J08408−4503 requires the presence of two distinct photon populations, a cold one (∼0.3 keV) most likely from a thermal halo around the neutron star and a hotter one (1.4–1.8 keV) from the accreting column. The outburst from XTE J1739−302 could be monitored with a very good sampling, thus revealing a shape which can be explained with a second wind component in this SFXT, in analogy to what we have suggested in the periodic SFXT IGR J11215−5952. The outburst recurrence time‐scale in IGR J17544−2619 during our monitoring campaign with  Swift  suggests a long orbital period of ∼150 d (in a highly eccentric orbit), compatible with what previously observed with  INTEGRAL .

Supergiant Fast X‐ray Transients in outburst: new Swift observations of XTE J1739−302, IGR J17544−2619 and IGR J08408−4503