  We present a detailed analysis of a 3.5 s long burst from SGR1900+14 which
occurred on 2001 July 2. The 2-150 keV time-integrated energy spectrum is well
described by the sum of two blackbodies whose temperatures are approximately
4.3 and 9.8 keV. The time-resolved energy spectra are similarly well fit by the
sum of two blackbodies. The higher temperature blackbody evolves with time in a
manner consistent with a shrinking emitting surface. The interpretation of
these results in the context of the magnetar model suggests that the two
blackbody fit is an approximation of an absorbed, multi-temperature spectrum
expected on theoretical grounds rather than a physical description of the
emission. If this is indeed the case, our data provide further evidence for a
strong magnetic field, and indicate that the entire neutron was radiating
during most of the burst duration.
