1,468 research outputs found
Anthropological Investigations of late heathen graves in Upernavik District.
The Eskimos came to Greenland in several waves, each group carrying with it its own culture. Skeletal materials are however only available from the lnugsuk Culture, the latest culture period. As already mentioned, the investigations of the skeletal materials described above primarily concern the lnugsuk people as they were like shortly after immigrating to Greenland. Their contact with white men essentially takes place during the last two centuries, and coincides with the introduction of Christianity. Thus, by analyzing the skeletal remains of the last heathen Greenlanders, one arrives at a picture of the development of the Inugsuk people throughout half a millenium in Greenland, and at the same time has a basis of comparison between the last pure Eskimos and the present-day Greenlanders. Several investigations of the physical anthropology of these immigrated peoples have already been published ( JØRGENSEN, 1954; LAUGHLIN & JØRGENSEN, 1956; SKELLER, 1954; GESSAIN, 1960).The Eskimos came to Greenland in several waves, each group carrying with it its own culture. Skeletal materials are however only available from the lnugsuk Culture, the latest culture period. As already mentioned, the investigations of the skeletal materials described above primarily concern the lnugsuk people as they were like shortly after immigrating to Greenland. Their contact with white men essentially takes place during the last two centuries, and coincides with the introduction of Christianity. Thus, by analyzing the skeletal remains of the last heathen Greenlanders, one arrives at a picture of the development of the Inugsuk people throughout half a millenium in Greenland, and at the same time has a basis of comparison between the last pure Eskimos and the present-day Greenlanders. Several investigations of the physical anthropology of these immigrated peoples have already been published ( JØRGENSEN, 1954; LAUGHLIN & JØRGENSEN, 1956; SKELLER, 1954; GESSAIN, 1960).The Eskimos came to Greenland in several waves, each group carrying with it its own culture. Skeletal materials are however only available from the lnugsuk Culture, the latest culture period. As already mentioned, the investigations of the skeletal materials described above primarily concern the lnugsuk people as they were like shortly after immigrating to Greenland. Their contact with white men essentially takes place during the last two centuries, and coincides with the introduction of Christianity. Thus, by analyzing the skeletal remains of the last heathen Greenlanders, one arrives at a picture of the development of the Inugsuk people throughout half a millenium in Greenland, and at the same time has a basis of comparison between the last pure Eskimos and the present-day Greenlanders. Several investigations of the physical anthropology of these immigrated peoples have already been published ( JØRGENSEN, 1954; LAUGHLIN & JØRGENSEN, 1956; SKELLER, 1954; GESSAIN, 1960)
Virtues and Flaws of the Pauli Potential
Quantum simulations of complex fermionic systems suffer from a variety of
challenging problems. In an effort to circumvent these challenges, simpler
``semi-classical'' approaches have been used to mimic fermionic correlations
through a fictitious ``Pauli potential''. In this contribution we examine two
issues. First, we address some of the inherent difficulties in a widely used
version of the Pauli potential. Second, we refine such a potential in a manner
consistent with the most basic properties of a cold Fermi gas, such as its
momentum distribution and its two-body correlation function.Comment: 16 pages, 6 figure
Using Dissolved Organic Carbon Concentration and Character Data to Assess Land Use Change Effects on Coastal Waters
2016 South Carolina Water Resources Conference
South Carolina Water Resources at a Crossroads: Response, Readiness and Recover
Creating Open Digital Library Using XML: Implementation of OAi-PMH Protocol at CERN
This article describes the implementation of the OAi-PMH protocol within the CERN Document Server (CDS). In terms of the protocol, CERN acts both as a data provider and service provider and the two core applications are described. The application of XML Schema and XSLT technology is emphasized
Cooperative Dynamics in Unentangled Polymer Fluids
We present a Generalized Langevin Equation for the dynamics of interacting
semiflexible polymer chains, undergoing slow cooperative dynamics. The
calculated Gaussian intermolecular center-of-mass and monomer potentials, wich
enter the GLE, are in quantitative agreement with computer simulation data. The
experimentally observed, short-time subdiffusive regime of the polymer
mean-square displacements, emerges here from the competition between the
intramolecular and the intermolecular mean-force potentials.Comment: 9 pages, latex, 3 figure
Proton fraction in the inner neutron-star crust
Monte Carlo simulations of neutron-rich matter of relevance to the inner
neutron-star crust are performed for a system of A=5,000 nucleons. To determine
the proton fraction in the inner crust, numerical simulations are carried out
for a variety of densities and proton fractions. We conclude---as others have
before us using different techniques---that the proton fraction in the inner
stellar crust is very small. Given that the purported "nuclear pasta" phase in
stellar crusts develops as a consequence of the long-range Coulomb interaction
among protons, we question whether pasta formation is possible in such
proton-poor environments. To answer this question, we search for physical
observables sensitive to the transition between spherical nuclei and exotic
pasta structures. Of particular relevance is the static structure factor
S(k)---an observable sensitive to density fluctuations. However, no dramatic
behavior was observed in S(k). We regard the identification of physical
observables sensitive to the existence---or lack-thereof---of a pasta phase in
proton-poor environments as an open problem of critical importance.Comment: 24 pages and 7 figure
Nonuniform Neutron-Rich Matter and Coherent Neutrino Scattering
Nonuniform neutron-rich matter present in both core-collapse supernovae and
neutron-star crusts is described in terms of a semiclassical model that
reproduces nuclear-matter properties and includes long-range Coulomb
interactions. The neutron-neutron correlation function and the corresponding
static structure factor are calculated from molecular dynamics simulations
involving 40,000 to 100,000 nucleons. The static structure factor describes
coherent neutrino scattering which is expected to dominate the neutrino
opacity. At low momentum transfers the static structure factor is found to be
small because of ion screening. In contrast, at intermediate momentum transfers
the static structure factor displays a large peak due to coherent scattering
from all the neutrons in a cluster. This peak moves to higher momentum
transfers and decreases in amplitude as the density increases. A large static
structure factor at zero momentum transfer, indicative of large density
fluctuations during a first-order phase transition, may increase the neutrino
opacity. However, no evidence of such an increase has been found. Therefore, it
is unlikely that the system undergoes a simple first-order phase transition. It
is found that corrections to the commonly used single heavy nucleus
approximation first appear at a density of the order of g/cm and
increase rapidly with increasing density. Thus, neutrino opacities are
overestimated in the single heavy nucleus approximation relative to the
complete molecular dynamics simulations.Comment: 17 pages, 23 included ps figure
All-electron GW calculation based on the LAPW method: application to wurtzite ZnO
We present a new, all-electron implementation of the GW approximation and
apply it to wurtzite ZnO. Eigenfunctions computed in the local-density
approximation (LDA) by the full-potential linearized augmented-plane-wave
(LAPW) or the linearized muffin-tin-orbital (LMTO) method supply the input for
generating the Green function G and the screened Coulomb interaction W. A mixed
basis is used for the expansion of W, consisting of plane waves in the
interstitial region and augmented-wavefunction products in the
augmentation-sphere regions. The frequency-dependence of the dielectric
function is computed within the random-phase approximation (RPA), without a
plasmon-pole approximation. The Zn 3d orbitals are treated as valence states
within the LDA; both core and valence states are included in the self-energy
calculation. The calculated bandgap is smaller than experiment by about 1eV, in
contrast to previously reported GW results. Self-energy corrections are
orbital-dependent, and push down the deep O 2s and Zn 3d levels by about 1eV
relative to the LDA. The d level shifts closer to experiment but the size of
shift is underestimated, suggesting that the RPA overscreens localized states.Comment: 10 pages, 3 figures, submitted to Phys. Rev.
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