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Evidence for a 2:3 resonance in Sco X-1 kHz QPOs

M. A. Abramowicz·T. Bulik·M. Bursa·W. Kluzniak
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Abstract

We find evidence that the two high frequency QPOs in Sco X-1 are, more often than not, approximately in the 2:3 frequency ratio familiar from studies of black hole candidates (e.g., XTE J1550-564, Remillard et al. 2002). This implies that the double kHz QPO phenomenon in neutron stars has its origin in properties of strong-field gravity and has little to do with the rotation of a stellar surface or any magnetic field structure anchored in the star.

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M. A. Abramowicz, T. Bulik, M. Bursa, W. Kluzniak. 2002-06-28. Evidence for a 2:3 resonance in Sco X-1 kHz QPOs. https://doi.org/10.1051/0004-6361%3A20030737

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