6,648 research outputs found
Calculation of NMR Properties of Solitons in Superfluid 3He-A
Superfluid 3He-A has domain-wall-like structures, which are called solitons.
We calculate numerically the structure of a splay soliton. We study the effect
of solitons on the nuclear-magnetic-resonance spectrum by calculating the
frequency shifts and the amplitudes of the soliton peaks for both longitudinal
and transverse oscillations of magnetization. The effect of dissipation caused
by normal-superfluid conversion and spin diffusion is calculated. The
calculations are in good agreement with experiments, except a problem in the
transverse resonance frequency of the splay soliton or in magnetic-field
dependence of reduced resonance frequencies.Comment: 15 pages, 10 figures, updated to the published versio
Surface-enhanced pair transfer in quadrupole states of neutron-rich Sn isotopes
We investigate the neutron pair transfer modes associated with the low-lying
quadrupole states in neutron-rich Sn isotopes by means of the quasiparticle
random phase approximation based on the Skyrme-Hartree-Fock-Bogoliubov mean
field model. The transition strength of the quadrupole pair-addition mode
feeding the state is enhanced in the Sn isotopes with . The
transition density of the pair-addition mode has a large spatial extension in
the exterior of nucleus, reaching far to fm. The quadrupole
pair-addition mode reflects sensitively a possible increase of the effective
pairing interaction strength in the surface and exterior regions of
neutron-rich nuclei.Comment: 14 page
Bibliography of Sources on Dena’ina and Cook Inlet Anthropology Through 2016
This version 4.3 will be the final version for this bibliography, a project that was begun in 1993 by Greg Dixon. We have intentionally excluded all potential references for the year 2017. This version is about 29 pages longer and has about 211 entries added since the previous version 3.1 of 2012. Aaron Leggett has added over fifty sources many being rare items from newpapers and magazines. Also many corrections and additions were made to entries in earlier versions.I wish to thank Kenaitze Indian Tribe and the “Dena’ina Language Revitalization Project” for their support for several projects during 2017-2018, including this Vers. 4.3. Previous versions have had partial support from "Dena'ina Archiving, Training and Access" project (NSF-OPP 0326805, 2004) and from Lake Clark National Park. I thank Katherine Arndt of Alaska & Polar Regions at UAF for her careful proofreading
Atom interferometric detection of the pairing order parameter in a Fermi gas
We propose two interferometric schemes to experimentally detect the onset of
pair condensation in a two spin-component Fermi gas. Two atomic wave-packets
are coherently extracted from the gas at different positions and are mixed by a
matter-wave beam splitter: we show that the spatial long range order of the
atomic pairs in the gas then reflects in the atom counting statistics in the
output channels of the beam splitter. Alternatively, the same long range order
is also shown to create a matter-wave grating in the overlapping region of the
two extracted wave-packets, grating that can be revealed by a light scattering
experiment
Spin 1/2 Fermions in the Unitary Regime: A Superfluid of a New Type
We have studied, in a fully non-perturbative calculation, a dilute system of
spin 1/2 interacting fermions, characterized by an infinite scattering length
at finite temperatures. Various thermodynamic properties and the condensate
fraction were calculated and we have also determined the critical temperature
for the superfluid-normal phase transition in this regime. The thermodynamic
behavior appears as a rather surprising and unexpected melange of fermionic and
bosonic features. The thermal response of a spin 1/2 fermion at the BCS-BEC
crossover should be classified as that of a new type of superfluid.Comment: 4 pages, 1 figure, published versio
"Valuing Beach Closures on the Padre Island National Seashore"
In this paper we estimate the economic loss of hypothetical beach closures on the Padre Island National Seashore on the Gulf Coast of Texas. We use a travel cost random utility maximization (RUM) model with data from a random phone survey of Texas residents completed in 2001. We simulate realistic closures that may occur in event of an oil spill or other disruption. For comparison we valued the loss of beach closures in the heavily populated Galveston area. The aggregate losses on Padre Island were highest on weekend days in July estimated at ). They were lowest on weekdays in September at 28. A similar closure of beaches near Galveston resulted in losses of 852,000 (weekend day) with a per trip loss of $30.random utility model, beach use, non-market valuation
Quantitative Probe of Pairing Correlations in a Cold Fermionic Atom Gas
A quantitative measure of the pairing correlations present in a cold gas of
fermionic atoms can be obtained by studying the dependence of RF spectra on
hyperfine state populations. This proposal follows from a sum rule that relates
the total interaction energy of the gas to RF spectrum line positions. We argue
that this indicator of pairing correlations provides information comparable to
that available from the spin-susceptibility and NMR measurements common in
condensed-matter systems.Comment: 5 pages, 1 figur
The Vortex State in a Strongly Coupled Dilute Atomic Fermionic Superfluid
We show that in a dilute Fermionic superfluid, when the Fermions interact
with an infinite scattering length, a vortex state is characterized by a strong
density depletion along the vortex core. This feature can make a direct
visualization of vortices in Fermionic superfluids possible.Comment: 4 pages, 3 figures, published version, some small changes and new and
updated reference
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