On the Persistence of QPOs During the SGR 1806-20 Giant Flare
arXiv:1808.09483 · doi:10.3847/1538-4357/aaf5ce
Abstract
The discovery of quasi-periodic brightness oscillations (QPOs) in the X-ray emission accompanying the giant flares of the soft gamma-ray repeaters SGR 1806-20 and SGR 1900+14 has led to intense speculation about their nature and what they might reveal about the interiors of neutron stars. Here we take a fresh look at the giant flare data for SGR 1806-20, and in particular we analyze short segments of the post-peak emission using a Bayesian procedure that has not previously been applied to these data. We find at best weak evidence that any QPO persists for more than second; instead, almost all the data are consistent with a picture in which there are numerous independently-excited modes that decay within a few tenths of a second. This has interesting implications for the rapidity of decay of the QPO modes, which could occur by the previously-suggested mechanism of coupling to the MHD continuum. The strongest QPOs favor certain rotational phases, which might suggest special regions of the crust or of the magnetosphere. We also find several previously unreported QPOs in these data, which may help in tracking down their origin.
20 pages, 5 figures, published in The Astrophysical Journal
References in corpus (12)
- Neutron Star Asteroseismology. Axial Crust Oscillations in the Cowling Approximation
- Torsional Oscillations of Relativistic Stars with Dipole Magnetic Fields
- QPOs during magnetar flares are not driven by mechanical normal modes of the crust
- On the theory of magnetar QPOs
- Magnetars oscillations in the presence of a crust
- Spectrum of shear modes in the neutron-star crust: Estimating the nuclear-physics uncertainties
- Magnetar oscillations pose challenges for strange stars
- Probing nuclear bubble structure via neutron star asteroseismology
- Intermittency and Lifetime of the 625 Hz QPO in the 2004 Hyperflare from the Magnetar SGR 1806-20 as evidence for magnetic coupling between the crust and the core
- Quasi-periodic oscillations in superfluid, relativistic magnetars with nuclear pasta phases
- Search for quasi-periodic signals in magnetar giant flares
- Magneto-elastic oscillations modulating the emission of magnetars
Cited by in corpus (22)
- Repeating Fast Radio Bursts from Magnetars with Low Magnetospheric Twist
- The Fast Radio Burst Luminosity Function and Death Line in the Low-Twist Magnetar Model
- Kilohertz quasiperiodic oscillations in short gamma-ray bursts
- Quasi-periodic oscillations of the X-ray burst from the magnetar SGR J1935+2154 and associated with the fast radio burst FRB 200428
- Fast Radio Burst Trains from Magnetar Oscillations
- Quantum nucleation of up-down quark matter and astrophysical implications
- GW190814: Circumstantial Evidence for Up-Down Quark Star
- Time-dependent extension of the self-consistent band theory for neutron star matter: Anti-entrainment effects in the slab phase
- Searching for quasi-periodic oscillations in astrophysical transients using Gaussian processes
- Pitfalls of periodograms: The non-stationarity bias in the analysis of quasi-periodic oscillations
- Magnetar QPOs and neutron star crust elasticity
- Search for Long-duration Gravitational-wave Signals Associated with Magnetar Giant Flares
- Hybrid Pulsar-Magnetar Model for FRB 20191221A
- Evidence for a strong 19.5 Hz flux oscillation in Swift BAT and Fermi GBM gamma-ray data from GRB 211211A
- Evidence for a brief appearance of gamma-ray periodicity after a compact star merger
- Torsional oscillations of magnetized neutron stars with mixed poloidal-toroidal fields
- Tangled magnetic field model of QPOs
- Quasi-Periodic Peak Energy Oscillations in X-ray Bursts from SGR J1935+2154
- Detection of Quasi-periodic Oscillations in SGR 150228213
- Detection of a Millisecond Periodicity in BATSE Short Gamma-Ray Bursts
- Estimation of neutron star mass and radius of FRB 20240114A by identification of crustal oscillations
- Nonlinear coupling between magnetar QPOs