Recent X-ray observations by Fermi/GBM discovered a new torque reversal of 4U1626-67 after 18 years of steady spinning down. Using Swift/BAT observations wewere able to center this new torque reversal on Feb 4 2008, lastingapproximately 150 days. From 2004 up to the end of 2007, the spin-down rateaveraged at a mean rate of ~dnu/dt=-4.8e-13 Hz s-1 until the torque reversalreported here. Since then it has been following a steady spin-up at a mean rateof ~dnu/dt= 4e-13 Hz s-1. The properties of this torque reversal, as well asthe lack of correlation between the X-ray flux and the torque applied to theneutron star before this transition, challenges our understanding of thephysical mechanisms operating in this system.
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