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Published online by Cambridge University Press: 12 May 2006
An analysis of the high-energy emission from IGR J16393–4643 is presented using data from INTEGRAL and XMM-Newton. The source is persistent in the 20–40 keV band at an average flux of $5.1\times10^{-11}$ergs cm$^{-2}$ s$^{-1}$, with variations in intensity by at least an order of magnitude. A pulse period of 912$\,{\pm}\,$3 s was discovered in the ISGRI and EPIC light curves. The source spectrum is a strongly-absorbed ($N_{\mathrm{H}}=(2.5\,{\pm}\,0.2)\times10^{23}$ cm$^{-2}$) power law that features a high-energy cutoff above 15 keV. Two iron emission lines at 6.4 and 7.1 keV, an iron absorption edge $\gtrsim$7.1 keV, and a soft excess emission of $7\times10^{-15}$ergs cm$^{-2}$ s$^{-1}$ between 0.5–2 keV, are detected in the EPIC spectrum. The shape of the spectrum does not change with the pulse. Its persistence, pulsation, and spectrum place IGR J16393–4643 among the class of heavily-absorbed HMXBs. The improved position from EPIC is R.A. (J2000)$=16^{\mathrm{h}}39^{\mathrm{m}}05.4^{\mathrm{s}}$ and Dec.$=-46^{\circ}42'12''$ ($4''$ uncertainty) which is compatible with that of 2MASS J16390535–4642137.