2009/08/27 by D. Altamirano, M. Linares, A. Patruno +6
Physics and Astronomy · #Astrophysical Phenomena and Observations #Gamma-ray bursts and supernovae #Neutron star #Pulsar #Pulsars and Gravitational Waves Research #Spectral analysis #Spectral density #Spectral line #Thermonuclear fusion #Transient (computer programming) #Type (biology) #astro-ph.HE
paper · pdf · doi:10.1111/j.1365-2966.2009.15627.x
9 pages, 7 figures - accepted for publication in MNRAS
arxiv created 2009/08/27 · openalex publication_date 2009/11/18 · arxiv updated 2015/05/14 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present a detailed study of the X-ray energy and power spectral properties of the neutron star transient IGR J17191−2821. We discovered four instances of pairs of simultaneous kilohertz quasi-periodic oscillations (kHz QPOs). The frequency difference between these kHz QPOs is between 315 and 362 Hz. We also report on the detection of five thermonuclear type I X-ray bursts and the discovery of burst oscillations at ∼294 Hz during three of them. Finally, we report on a faint and short outburst precursor, which occurred about two months before the main outburst. Our results on the broad-band spectral and variability properties allow us to firmly establish the atoll source nature of IGR J17191−2821.