Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-06-23
Astronomy and Astrophysics
Astrophysics
7 pages (including figs). Revised, accepted for publication in ApJ
Scientific paper
10.1086/323877
We have detected large-amplitude 0.3-1.2 mHz quasi-periodic oscillations (QPOs) from the low-mass X-ray binary pulsar 4U 1626-67/KZ TrA, using UV photometry from HST and ground-based optical photometry. These 1 mHz QPOs, which have coherence (Nu/DeltaNu)=8, are entirely distinct from the 130 mHz pulsar spin frequency, a previously known 48 mHz QPO, and the 42 min binary period (independently confirmed here). Unlike the 48 mHz and 130 mHz oscillations which are present in both the optical/UV and the X-ray emission, the 1 mHz QPOs are not detected in simultaneous observations with RXTE. The rms amplitude of the mHz QPO decreases from 15% in the far UV to 3% in the optical, while the upper limit on a corresponding X-ray QPO is as low as 0.8%. We suggest that the mHz oscillations are due to warping of the inner accretion disk. We also report the detection of coherent upper and lower sidebands of the 130 mHz optical pulsations, with unequal amplitude and a spacing of 1.93 mHz around the main pulsation. The origin of these sidebands remains unclear.
Chakrabarty Deepto
Charles Philip A.
Homer Lee
O'Donoghue Darragh
No associations
LandOfFree
Millihertz Optical/UV Oscillations in 4U 1626-67: Evidence for a Warped Accretion Disk does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Millihertz Optical/UV Oscillations in 4U 1626-67: Evidence for a Warped Accretion Disk, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Millihertz Optical/UV Oscillations in 4U 1626-67: Evidence for a Warped Accretion Disk will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-625894