17 research outputs found
Multiwavelength Study on Solar and Interplanetary Origins of the Strongest Geomagnetic Storm of Solar Cycle 23
We study the solar sources of an intense geomagnetic storm of solar cycle 23
that occurred on 20 November 2003, based on ground- and space-based
multiwavelength observations. The coronal mass ejections (CMEs) responsible for
the above geomagnetic storm originated from the super-active region NOAA 10501.
We investigate the H-alpha observations of the flare events made with a 15 cm
solar tower telescope at ARIES, Nainital, India. The propagation
characteristics of the CMEs have been derived from the three-dimensional images
of the solar wind (i.e., density and speed) obtained from the interplanetary
scintillation data, supplemented with other ground- and space-based
measurements. The TRACE, SXI and H-alpha observations revealed two successive
ejections (of speeds ~350 and ~100 km/s), originating from the same filament
channel, which were associated with two high speed CMEs (~1223 and ~1660 km/s,
respectively). These two ejections generated propagating fast shock waves
(i.e., fast drifting type II radio bursts) in the corona. The interaction of
these CMEs along the Sun-Earth line has led to the severity of the storm.
According to our investigation, the interplanetary medium consisted of two
merging magnetic clouds (MCs) that preserved their identity during their
propagation. These magnetic clouds made the interplanetary magnetic field (IMF)
southward for a long time, which reconnected with the geomagnetic field,
resulting the super-storm (Dst_peak=-472 nT) on the Earth.Comment: 24 pages, 16 figures, Accepted for publication in Solar Physic
Electromagnetic Response of Layered Superconductors with Broken Lattice Inversion Symmetry
We investigate the macroscopic effects of charge density waves (CDW) and
superconductivity in layered superconducting systems with broken lattice
inversion symmetry (allowing for piezoelectricity) such as two dimensional (2D)
transition metal dichalcogenides (TMD). We work with the low temperature time
dependent Ginzburg-Landau theory and study the coupling of lattice distortions
and low energy CDW collective modes to the superconducting order parameter in
the presence of electromagnetic fields. We show that superconductivity and
piezoelectricity can coexist in these singular metals. Furthermore, our study
indicates the nature of the quantum phase transition between a commensurate CDW
phase and the stripe phase that has been observed as a function of applied
pressure.Comment: 9 pages, 1 figure. Final version. Accepted in Phys.Rev.
Relativistic Laser-Matter Interaction and Relativistic Laboratory Astrophysics
The paper is devoted to the prospects of using the laser radiation
interaction with plasmas in the laboratory relativistic astrophysics context.
We discuss the dimensionless parameters characterizing the processes in the
laser and astrophysical plasmas and emphasize a similarity between the laser
and astrophysical plasmas in the ultrarelativistic energy limit. In particular,
we address basic mechanisms of the charged particle acceleration, the
collisionless shock wave and magnetic reconnection and vortex dynamics
properties relevant to the problem of ultrarelativistic particle acceleration.Comment: 58 pages, 19 figure
Recommended from our members
Knock-on electrons in the target chamber
It is virtually certain that heavy ion beams will produce massive quantities of knock-on electrons for target chamber pressures above 1 torr. It was shown that the magnitude of the resulting current is more than sufficient to pinch the knock-on beam in most cases, assuming that a substantial fraction of this beam actually gets out ahead of the ion beam pulse. Although at least some of the ion beam experiences this defocusing, the overall effect on beam propagation is minimal if field reversal induced by the ion beam occurs near the beam head