The Supergiant Fast X-ray Transient with the shortest orbital period:
  Suzaku observes one orbit in IGRJ16479-4514
  The eclipsing hard X-ray source IGR J16479-4514 is the Supergiant Fast X-ray
Transient (SFXT) with the shortest orbital period (3.32 days). This allowed us
to perform a 250 ks long X-ray observation with Suzaku in 2012 February,
covering most of its orbit, including the eclipse egress. Outside the eclipse,
the source luminosity is around a few 1E34erg/s. The X-ray spectrum can be fit
with an absorbed power law together with a neutral iron emission line at 6.4
keV. The column density is constant at 1E23 cm-2 outside the X-ray eclipse.
During the eclipse it is lower, consistent with a scattering origin for the low
X-ray emission during the eclipse by the supergiant companion wind. The
scattered X-ray emission during the X-ray eclipse is used to directly probe the
density of the companion wind at the orbital separation, resulting in 7E-14
g/cm3, which translates into a ratio Mdot_w/v_terminal = 7E-17 solar masses/km
of the wind mass loss rate to the wind terminal velocity. This ratio, assuming
reasonable terminal velocities in the range 500-3000 km/s, translates into an
accretion luminosity two orders of magnitude higher than that observed. We
conclude that a mechanism reducing the accretion rate onto the compact object
is at work, likely due to the neutron star magnetosphere.
