Author/Authors :
G. Cusumano، نويسنده , , T. Di Salvo، نويسنده , , L. Burderi، نويسنده , , M. Orlandini، نويسنده , , Pamela S. Piraino، نويسنده , , N. Robba، نويسنده , , A. Santangelo، نويسنده ,
Abstract :
We report the detection of a cyclotron absorption line and its second harmonic in the average spectrum of the high mass X-ray binary 4U1907+09 observed by the BeppoSAX satellite. The broad band spectral capability of BeppoSAX allowed a good determination of the continuum against which the two absorption features are evident at ∼ 19 and ∼ 39 keV. Correcting for the gravitational redshift of a ∼ 1.4 M⊙ neutron star, the inferred surface magnetic field strength is Bsurf = 2.1 × 1012 G.
