248 research outputs found
Ramp wave loading experiments driven by heavy ion beams: a feasibility study
A new design for heavy-ion beam driven ramp wave loading experiments is suggested and analyzed. The proposed setup utilizes the long stopping ranges and the variable focal spot geometry of the high-energy uranium beams available at the GSI Helmholtzzentrum für Schwerionenforschung and Facility for Antiproton and Ion Research accelerator centers in Darmstadt, Germany. The release wave created by ion beams can be utilized to create a planar ramp loading of various samples. In such experiments, the predicted high pressure amplitudes (up to 10 Mbar) and short timescales of compression (<10 ns) will allow to test the time-dependent material deformation at unprecedented extreme conditions
Molecular CP-violating magnetic moment
A concept of CP-violating (T,P-odd) permanent molecular magnetic moments
is introduced. We relate the moments to the electric dipole moment
of electron (eEDM) and estimate for several diamagnetic polar
molecules. The moments exhibit a steep, Z^5, scaling with the nuclear charge Z
of the heavier molecular constituent. A measurement of the CP-violating
magnetization of a polarized sample of heavy molecules may improve the present
limit on eEDM by several orders of magnitude.Comment: 4 pages, no figures, submitted to PR
Coulomb plasmas in outer envelopes of neutron stars
Outer envelopes of neutron stars consist mostly of fully ionized, strongly
coupled Coulomb plasmas characterized by typical densities about 10^4-10^{11}
g/cc and temperatures about 10^4-10^9 K. Many neutron stars possess magnetic
fields about 10^{11}-10^{14} G. Here we briefly review recent theoretical
advances which allow one to calculate thermodynamic functions and electron
transport coefficients for such plasmas with an accuracy required for
theoretical interpretation of observations.Comment: 4 pages, 2 figures, latex2e using cpp2e.cls (included). Proc. PNP-10
Workshop, Greifswald, Germany, 4-9 Sept. 2000. Accepted for publication in
Contrib. Plasma Phys. 41 (2001) no. 2-
Recommended from our members
Fast six-channel pyrometer for warm-dense-matter experiments with intense heavy-ion beams
This paper describes a fast multi-channel radiation pyrometer that was developed for warmdense-matter experiments with intense heavy ion beams at Gesellschaft fur Schwerionenforschung mbH (GSI). The pyrometer is capable of measuring of brightness temperatures from 2000 K to 50000 K, at 6 wavelengths in visible and near-infrared parts of spectrum, with 5 nanosecond temporal resolution and several micrometers spatial resolution. The pyrometer's spectral discrimination technique is based on interference filters, which act as filters and mirrors to allow for simultaneous spectral discrimination of the same ray at multiple wavelengths
Modeling geoelectric fields in Ireland and the UK for space weather applications
Geoelectric fields at the Earth’s surface caused by geomagnetic storms have the potential to
disrupt and damage ground-based infrastructure such as electrical power distribution networks, pipelines,
and railways. Here we model geoelectric fields in Ireland and the UK during both quiet and active time
intervals of geomagnetic conditions using measurements from magnetic observatories and electromagnetic
tensor relationships. The analysis focused on (1) defining periods of the magnetic field variations that are
largely affected by the geomagnetic storms, between 30 and 30,000 s; (2) constraining the electromagnetic
tensor relationships that defines the Earth’s response to magnetic field variations; (3) implementing and
validating two approaches for modeling geoelectric fields based on measurements from magnetic
observatories and local and interstation electromagnetic transfer functions; and (4) estimating uncertainties
when modeling geoelectric fields. The use of interstation tensor relationships allowed us to differentiate
between regional and local geomagnetic sources. We found coherence values of 0.5–0.95, signal-to-noise
ratio of 1–15 dB, normalized root-mean-square values of 0.8–3.4, and root-mean-square values of
0.7–84 mV/km. Within these ranges of values, sites in close proximity (<100 km) to a magnetic observatory
and not affected by local storms will provide the most accurate results, while sites located at further
distances and affected by spatially localized features of the storm will be less accurate. These methods
enable us to more accurately model geomagnetically induced currents, and their associated uncertainties, in
the British and Irish power networks
- …