Suzaku Observation of a Supergiant Fast X-ray Transient, AX J1841.0-0536

We observed the supergiant fast X-ray transient (SFXT) AX J1841.0-0536 with Suzaku. Many short flares with durations of similar to 100 s were detected in the XIS and HXD bands. We found that the overall spectrum in the 1.0-40 keV band was fitted with an partially absorbed cut-off power-law plus an Fe I K alpha line and an absorption feature at the center energy of similar to 15 keV, that we interpret as possible evidence of a resonant cyclotron absorption feature. We then made time-resolved spectra and fit them with the same models as the overall spectrum. The photon indices of the power-law were distributed in 0-2 with the trend of "harder when brighter". On the other hand, no significant difference was found, either in the absorption column densities nor in the covering fractions between any of the phases.