We numerically model the coronal mass ejection (CME) event of October 28, 2003 that erupted from active region 10486 and propagated to Earth in less than 20 hours causing severe geomagnetic storms. The magnetohydrodynamic (MHD) model is formulated by first arriving at a steady state corona and solar wind employing synoptic magnetograms. We initiate two CMEs from the same active region, one appr...

The interaction of high-velocity neutron stars with the interstellar medium produces bow shock nebulae, where the relativistic neutron star wind is confined by ram pressure. We present multi-wavelength observations of the Guitar Nebula, including narrow-band Hα imaging with HST/WFPC2, which resolves the head of the bow shock. The HST observations are used to fit for the inclination of the pulsa...

Thanks to a new focused array of piezoelectric transducers, experimental results are reported here to evidence helical acoustical shock waves resulting from the nonlinear propagation of acoustical vortices (AVs). These shock waves have a three-dimensional spiral shape, from which both the longitudinal and azimuthal components are studied. The inverse filter technique used to synthesize AVs allo...

Near-equiatomic Ni-Ti, known for its shape memory behavior, can decompose to martensitic phases and/or second phase compounds. This phase competition is investigated in NixTi100-x (49<x<55) in as-quenched (AQ) and shock-loaded states. Dynamic loading was done with direct drive laser pulses of nanosecond duration; shocked samples were recovered for analysis. Unexpectedly, the lowest-Ni alloy (x ...

Monte-Carlo computations for highly relativistic parallel shock particle acceleration are presented for upstream flow gamma factors, Γ = (1 − V 2 1 /c2)−0.5 with values between 5 and 10. The results show that the spectral shape at the shock depends on whether or not the particle scattering is small angle with δθ < Γ−1 or large angle, which is possible if λ > 2rgΓ 2 where λ is the scattering mea...

conclusions this study suggests that obese patients in hs may have a higher risk of hemodynamic instability compared to their nonobese counterparts primarily due to obesity-induced increases in intra-abdominal pressure resulting in reduced venous return. results in hemorrhage simulation, moderate increases in bmi were found to produce greater decreases in map and co compared to the normal subje...

Typically, to study the effects of consecutive earthquakes, it is necessary to consider definite intensity levels of the first shock. Methods commonly used to define intensity involve scaling the first shock to a specified maximum interstorey drift. In this study the structure’s predefined elastic spectral acceleration caused by the first shock is also considered for scaling. This study aims to...

An experimental investigation of shock wave induced heating and compression in planar targets relevant to direct-drive inertial confinement fusion (ICF) was conducted on the OMEGA laser system. A physical understanding of shock wave heating, radiative heating, and heating by energetic electrons in direct-drive ICF is necessary because the achievement of energy gain requires accurate control of ...

In this chapter I give an overview of shock acceleration , including a discussion of the maximum energies possible and the shape of the spectrum near cut-oo, interactions of high energy cosmic rays with, and propagation through, the background radiation, and the resulting electron-photon cascade. Possible sources of the highest energy cosmic rays are discussed including active galaxies , gamma ...

We construct supersymmetric brane solutions in string and M-theory with moduli parameters that depend arbitrarily on the light-cone time. Our investigation aims in understanding time dependent phenomena in gauge theories at strong coupling within the gauge/gravity correspondence. For that reason we use, as a basic ingredient, multicenter supergravity solutions which model the Coulomb branch of ...