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The INTEGRAL LMXRB Monitoring Programme

A. Paizis·T. J. -L. Courvoisier·O. Vilhu·M. Chernyakova·T. Tikkanen·A. Bazzano·V. Beckmann·J. Chenevez·M. Cocchi·K. Ebisawa·R. Farinelli·F. Frontera·A. Gimenez·P. Goldoni·D. Hannikainen·E. Kuulkers·N. Lund·T. Oosterbroek·S. Piraino·J. Rodriguez·A. Santangelo·R. Walter·A. A. Zdziarski·J. A. Zurita Heras
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Abstract

Our collaboration is responsible for the study of a sample of 72 low mass X-ray binaries (LMXRB) using the INTEGRAL Core Programme data. In this paper we describe the monitoring programme we have started and the current variability and spectral results on a sample of 8 persistently bright LMXRBs hosting a neutron star (Z and Atoll sources). Current results show that among our sample of sources there seems to be no important difference in the variability of Z sources with respect to Atolls and the first colour-colour and hardness intensity diagrams built in the "traditional" energy bands display the expected patterns. Z sources seem to be harder than the bright Atolls of our sample (above 20 keV) and present no evident cut-off until about 50 keV. A hint of a non-thermal hard tail is seen in Sco X-1 with ISGRI and SPI, similarly to what was previously detected by D'Amico et al. (2001) with RXTE. These results, even if preliminary, show the importance of such a programme and the potential underlying it to understand these sources as a class.

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A. Paizis, T. J. -L. Courvoisier, O. Vilhu, M. Chernyakova, T. Tikkanen, A. Bazzano, V. Beckmann, J. Chenevez, M. Cocchi, K. Ebisawa, R. Farinelli, F. Frontera, A. Gimenez, P. Goldoni, D. Hannikainen, E. Kuulkers, N. Lund, T. Oosterbroek, S. Piraino, J. Rodriguez, A. Santangelo, R. Walter, A. A. Zdziarski, J. A. Zurita Heras. 2004-05-19. The INTEGRAL LMXRB Monitoring Programme. https://arxiv.org/abs/astro-ph/0405376

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