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arXiv · 0905.1491

Doppler and modulation tomography of XTE J1118+480 in quiescence

D. E. Calvelo·S. D. Vrtilek·D. Steeghs·M. A. P. Torres·J. Neilsen·A. V. Filippenko·J. I. Gonzalez Hernandez
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Abstract

We present Doppler and modulation tomography of the X-ray nova XTE J1118+480 with data obtained during quiescence using the 10-m Keck II telescope. The hot spot where the gas stream hits the accretion disc is seen in H-Alpha, H-Beta, He I Lambda-5876, and Ca II Lambda-8662, thus verifying the presence of continued mass transfer within the system. The disc is clearly seen in H-Alpha and Ca II Lambda-8662. We image the mass-donor star in narrow absorption lines of Na I Lambda-Lambda-5890, 5896, 8183, 8195 and Ca II Lambda-8662, implying an origin from the secondary itself rather than the interstellar medium. We also detect deviations in the centroid of the double peak of H-Alpha akin to those found by Zurita et al. 2002 suggesting disc eccentricity.

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D. E. Calvelo, S. D. Vrtilek, D. Steeghs, M. A. P. Torres, J. Neilsen, A. V. Filippenko, J. I. Gonzalez Hernandez. 2009-05-11. Doppler and modulation tomography of XTE J1118+480 in quiescence. https://doi.org/10.1111/j.1365-2966.2009.15304.x

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