086148

We propose a 60 ks observation to probe the nature of the youngest HMXB discovered with its associated SNR openParMCSNR J0513-6724closePar. The existing XMM-Newton observation shows tentative pulsations from the HMXB which needs confirmation. The estimated age is <6 kyr. A very young system can switch on as an accreting pulsar only when the spin period has reached a critical value. This implies an upper limit of B<5 10e11 G. A young NS observed with a low B strength would strongly imply magnetic field burial by an episode of post-supernova hyper-critical accretion comma which if confirmed will be the first ever to be observed in a HMXB. A dedicated observation of MCSNR J0513-6724 will provide the unique opportunity to probe the physics of accretion onto NS at early evolutionary stages.