English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

The eclipsing hard X-ray source IGR J16479-4514 is the Supergiant Fast X-rayTransient (SFXT) with the shortest orbital period (3.32 days). This allowed usto 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 fitwith an absorbed power law together with a neutral iron emission line at 6.4keV. 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 lowX-ray emission during the eclipse by the supergiant companion wind. Thescattered X-ray emission during the X-ray eclipse is used to directly probe thedensity of the companion wind at the orbital separation, resulting in 7E-14g/cm3, which translates into a ratio Mdot_w/v_terminal = 7E-17 solar masses/kmof the wind mass loss rate to the wind terminal velocity. This ratio, assumingreasonable terminal velocities in the range 500-3000 km/s, translates into anaccretion luminosity two orders of magnitude higher than that observed. Weconclude that a mechanism reducing the accretion rate onto the compact objectis at work, likely due to the neutron star magnetosphere.

The Supergiant Fast X-ray Transient with the shortest orbital period: Suzaku observes one orbit in IGRJ16479-4514