31,482 research outputs found
RESURRECTED RECORDS: “NEW” REPTILE OCCURRENCE RECORDS FOR MONTGOMERY COUNTY, INDIANA
Current and historic records of species occurrences in particular localities enable researchers to monitor changes in species distribution and abundance. While current fauna can be documented with sufficient effort, missing historical records represent data that can never again be obtained. It is with this importance in mind that we report for the first time records of eight reptile species in Montgomery County, Indiana, USA, that were documented in 1964, though no vouchered specimens persist. These species include: Sternotherus odoratus, Terrapene carolina carolina, Chrysemys picta marginata, Apalone spinifera spinifera, Thamnophis sauritus sauritus, Storeria dekayi wrightorum, Lampropeltis calligaster, Lampropeltis triangulum. We also provide a list of the 23 currently documented reptile species that occur (or have occurred recently) in Montgomery County
Superfluid Pairing in Neutrons and Cold Atoms
Ultracold atomic gases and low-density neutron matter are unique in that they
exhibit pairing gaps comparable to the Fermi energy which in this sense are the
largest in the laboratory and in nature, respectively. This strong pairing
regime, or the crossover between BCS and BEC regimes, requires non-perturbative
treatments. We describe Quantum Monte Carlo results useful to understand the
properties of these systems, including infinite homogeneous matter and trapped
inhomogeneous gases.Comment: 14 pages, 4 figures; chapter in "50 Years of Nuclear BCS", edited by
R. A. Broglia and V. Zelevinsk
Cold neutrons trapped in external fields
The properties of inhomogeneous neutron matter are crucial to the physics of
neutron-rich nuclei and the crust of neutron stars. Advances in computational
techniques now allow us to accurately determine the binding energies and
densities of many neutrons interacting via realistic microscopic interactions
and confined in external fields. We perform calculations for different external
fields and across several shells to place important constraints on
inhomogeneous neutron matter, and hence the large isospin limit of the nuclear
energy density functionals that are used to predict properties of heavy nuclei
and neutron star crusts. We find important differences between microscopic
calculations and current density functionals; in particular the isovector
gradient terms are significantly more repulsive than in traditional models, and
the spin-orbit and pairing forces are comparatively weaker.Comment: 5 pages, 4 figures, final version. Additional material reference
added in the published versio
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