The Dripping Handrail Model: Transient Chaos in Accretion Systems

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

11

Accretion, Accretion Disks, Stars: Binaries: Close, Galaxies: Active, Stars: Pulsars: General, X-Rays: Stars

Scientific paper

We define and study a simple dynamical model for accretion systems, the "dripping handrail" (DHR). The time evolution of this spatially extended system is a mixture of periodic and apparently random (but actually deterministic) behavior. The nature of this mixture depends on the values of its physical parameters the accretion rate, diffusion coefficient, and density threshold. The aperiodic component is a special kind of deterministic chaos called transient chaos. The model can simultaneously exhibit both the quasi-periodic oscillations and very low frequency noise that characterize the power spectra of fluctuations of several classes of accretion systems in astronomy. For this reason, our model may be relevant to many such astrophysical systems, including binary stars with accretion onto a compact object white dwarf, neutron star, or black hole as well as active galactic nuclei. We describe the systematics of the DHR's temporal behavior by exploring its physical parameter space using several diagnostics: power spectra, wavelet "scalegrams," and Lyapunov exponents (which characterize the degree of chaos inherent in the time evolution of a system). In addition, we note that for large accretion rates, the DHR has periodic modes; the effective pulse shapes for these by folding the time series at the known period bear a resemblance to the similarly determined shapes for some X-ray pulsars. The pulsing observed in some of these systems may be such periodic-mode accretion and not be due to pure rotation as in the standard pulsar model.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The Dripping Handrail Model: Transient Chaos in Accretion Systems 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 The Dripping Handrail Model: Transient Chaos in Accretion Systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Dripping Handrail Model: Transient Chaos in Accretion Systems will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1459081

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.