In a recent paper we have calculated the power density spectrum of Gamma-Ray Bursts arising from multiple shocks in a relativistic wind. The wind optical thickness is one of the factors to which the power spectrum is most sensitive, therefore we have further developed our model by taking in account the photon down-scattering on the cold electrons in the wind. For an almost optically thick wind ...

Matter accreting onto black holes may develop shocks due to the centrifugal barrier. A part of inflowing matter in the post-shock flow is deflected along the axis in the form of jets. Post-shock flow which behaves like a Compton cloud has ‘hot’ electrons emiting high energy photons. We study the effect of these ‘hot’ photons on the outflowing matter. Radiation from this region could accelerate ...

We present Smoothed Particle Hydrodynamics (SPH) simulations of the response of gas discs to a spiral potential. These simulations show that the commonly observed spurs and feathering in spiral galaxies can be understood as being due to structures present in the spiral arms that are sheared by the divergent orbits in a spiral potential. Thus, dense molecular cloud-like structures generate the p...

In the current paradigm of cold dark matter cosmology, large-scale structures are assembling through hierarchical clustering of matter. In this process, an important role is played by megaparsec (Mpc)-scale cosmic shock waves, arising in gravity-driven supersonic flows of intergalactic matter onto dark matter-dominated collapsing structures such as pancakes, filaments, and clusters of galaxies....

95 Pacific Economic Bulletin volume 24 number 2 july 2009 © the australian national University This article examines the volatility in Fiji’s foreign reserves—in particular, whether shocks have an asymmetrical effect on volatility and whether shocks have a persistent impact on volatility. In the pre-coup period (1975–86), shocks had a temporary effect on volatility; in the coup period (1987–200...

In this paper, the authors examine the impacts of large price changes (or shocks) on the abnormal returns (ARs) of a set of 39 national stock indices. Their initial results support returns continuations for both positive and negative shocks in line with prior results. After controlling for market size, their findings provide support for over-reaction, return continuations and market efficiency,...

[1] Interplanetary (IP) shocks are mainly responsible for the sudden compression of the magnetosphere, causing storm sudden commencement (SC) and sudden impulses (SIs) which are detected by ground-based magnetometers. On the basis of the list of 222 IP shocks compiled by Gopalswamy et al. (2010), we have investigated the dependence of SC/SIs amplitudes on the speed of the coronal mass ejections...

A central problem ill empirical macroeconomics is to determine when and how much the exchange rate is misaligned. This paper clarifies and calculates the concept of’ the equilibrium real exchange rate, using a structural vector auto regression (VAR) model. By imposing long—run restrictions on a VAR model for Iran, lour structural shocks are identified: nominal demand, real demand, supply and oi...