Context. The supermassive black hole at the Galactic center, Sgr A*, shows frequent radiation outbursts, often called ’flares’. In the near-infrared some of these flares were reported as showing intrinsic quasi-periodicities. The flux peaks associated with the quasi-periodic behavior were found to be highly polarized. Aims. The aim of this work is to present new evidence to support previous fin...

Aims. We model the X-ray reprocessing from a strong co-rotating flare above an accretion disk in active galactic nuclei. By performing detailed radiative transfer computations we explore the horizontal structure and evolution of the underlying hot spot. The main goal is to study how the resulting spectral features manifest themselves in short exposure time spectra. Methods. We analyze both the ...

This paper is concerned with the problem of identifying names which occur frequently in an ordered list of names. Such names are called hot spots. Hot spots can be identiied easily by counting the occurrences of each name and then selecting those with large counts. However, this simple solution requires space proportional to the number of names that occur in the list. In this paper, we present ...

A new analysis method is introduced for investigating whether major flares are clustered in certain fixed regions of the Sun in rigidly-rotating coordinate systems. This method is applied to analysis of major flares of solar cycles 19–23. Northern and southern hemispheres are separately analyzed, and it is found that longitude distributions of flares in the two hemispheres are different. Theref...

[1] Net rotation (NR) of the lithosphere is found in hot spot reference frames, important for tectonics and plume models, but difficult to constrain. Using mantle flow and crystallographic texture modeling, I show that NRs lead to mantle shearing which is recorded in azimuthal seismic anisotropy. The NR amplitude in some hot spot models is so large that it degrades the model fit to anisotropy s...

[1] Although an average westward rotation of the Earth’s lithosphere is indicated by global analyses of surface features tied to the deep mantle (e.g., hot spot tracks), the rate of lithospheric drift is uncertain despite its importance to global geodynamics. We use a global viscous flow model to predict asthenospheric anisotropy computed from linear combinations of mantle flow fields driven by...

Hot spot content ion on a network-based sharedmemory architecture occurs when a large number of processors try to access a globally shared variable across the network. While Multistage Interconnection Network (MIN) and Hierarchical Ring (HR) structures are two important bases on which to build large scale shared-memory multiprocessors, the different interconnection networks and cache/memory sys...

To reproduce the observed spectra and light curves originated in neighborhood of compact objects requires accurate relativistic ray-tracing codes. In this work, we present Skylight, a new numerical code for general-relativistic ray tracing radiative transfer arbitrary space-time geometries coordinate systems. The is capable producing images, spectra, from astrophysical models as seen by distant...