English

A varying kHz peak separation in 4U 1608-52

Astrophysics 2009-10-30 v1

Abstract

Using a new technique to improve the sensitivity to weak Quasi-Periodic Oscillations (QPO) we discovered a new QPO peak at about 1100 Hz in the March 1996 outburst observations of 4U 1608-52, simultaneous with the ~ 600-900 Hz peak previously reported from these data. The frequency separation between the upper and the lower QPO peak varied significantly from 232.7±11.5232.7 \pm 11.5 Hz on March 3, to 293.1±6.6293.1 \pm 6.6 Hz on March 6. This is the first case of a variable kHz peak separation in an atoll source.

Keywords

Cite

@article{arxiv.astro-ph/9712140,
  title  = {A varying kHz peak separation in 4U 1608-52},
  author = {M. Mendez and M. van der Klis and J. van Paradijs and W. H. G. Lewin and B. A. Vaughan and E. Kuulkers and W. Zhang and F. K. Lamb and D. Psaltis},
  journal= {arXiv preprint arXiv:astro-ph/9712140},
  year   = {2009}
}

Comments

Aipproc LaTeX (4 pages, 2 ps-figures), to appear in "Accretion Processes in Astrophysical Systems", Proc. of the 8th Annual Astrophysics Conference in Maryland, S. S. Holt & T. Kallman (eds.)