IV. CONCLUSIONS

A broad and skewed spectral feature was detected in GRS 1915+105 on April 19, 1998. Here, the iron line EW was significantly larger than in all other BeppoSAX observations of this source. The data were analyzed and the location of the inner edge of emission was determined by fitting the line profile with a relativistic model. The best-fit inner emitting radius is above the innermost stable orbit, whatever value of a/m is assumed. Neither a high value the of BH spin nor anisotropic illumination by a central source (as discussed in Martocchia & Matt 1996) are necessary to obtain a better fit.

We conclude that the line is emitted from neutral or low ionized iron, from a region of the accretion disc close to, but not including the innermost stable orbit, either for a spinning or a static BH (even if the disc parameters are somewhat dependent on the adopted model for the continuum, and must be taken with caution). We refer to Martocchia et al. (2001) for a more detailed discussion of the adopted data fitting procedure and for interpretation.

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