25,534 research outputs found
2H and 13C NMR studies on the temperature-dependent water and protein dynamics in hydrated elastin, myoglobin and collagen
2H NMR spin-lattice relaxation and line-shape analyses are performed to study
the temperature-dependent dynamics of water in the hydration shells of
myoglobin, elastin, and collagen
Production of radioactive isotopes through cosmic muon spallation in KamLAND
Radioactive isotopes produced through cosmic muon spallation are a background for rare-event detection in ν detectors, double-β-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of ^(11)C. Data from the Kamioka liquid-scintillator antineutrino detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillators, and for checking estimates from current simulations based upon MUSIC, FLUKA, and GEANT4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be Y_n=(2.8±0.3)×10^(-4) μ^(-1) g^(-1) cm^2. For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment
Entanglement signature in the mode structure of a single photon
It is shown that entanglement, which is a quantum correlation property of at
least two subsystems, is imprinted in the mode structure of a single photon.
The photon, which is emitted by two coupled cavities, carries the information
on the concurrence of the two intracavity fields. This can be useful for
recording the entanglement dynamics of two cavity fields and for entanglement
transfer.Comment: 4 pages, 3 figure
How Sensitive are Di-Leptons from Rho Mesons to the High Baryon Density Region?
We show that the measurement of di-leptons might provide only a restricted
view into the most dense stages of heavy ion reactions. Thus, possible studies
of meson and baryon properties at high baryon densities, as e.g. done at
GSI-HADES and envisioned for FAIR-CBM, might observe weaker effects than
currently expected in certain approaches. We argue that the strong absorption
of resonances in the high baryon density region of the heavy ion collision
masks information from the early hot and dense phase due to a strong increase
of the total decay width because of collisional broadening. To obtain
additional information, we also compare the currently used approaches to
extract di-leptons from transport simulations - i.e. shining, only vector
mesons from final baryon resonance decays and instant emission of di-leptons
and find a strong sensitivity on the method employed in particular at FAIR and
SPS energies. It is shown explicitly that a restriction to rho meson (and
therefore di-lepton) production only in final state baryon resonance decays
provide a strong bias towards rather low baryon densities. The results
presented are obtained from UrQMD v2.3 calculations using the standard set-up.Comment: 8 pages, 6 figures, expanded versio
Third type of domain wall in soft magnetic nanostrips
Magnetic domain walls (DWs) in nanostructures are low-dimensional objects
that separate regions with uniform magnetisation. Since they can have different
shapes and widths, DWs are an exciting playground for fundamental research, and
became in the past years the subject of intense works, mainly focused on
controlling, manipulating, and moving their internal magnetic configuration. In
nanostrips with in-plane magnetisation, two DWs have been identified: in thin
and narrow strips, transverse walls are energetically favored, while in thicker
and wider strips vortex walls have lower energy. The associated phase diagram
is now well established and often used to predict the low-energy magnetic
configuration in a given magnetic nanostructure. However, besides the
transverse and vortex walls, we find numerically that another type of wall
exists in permalloy nanostrips. This third type of DW is characterised by a
three-dimensional, flux closure micromagnetic structure with an unusual length
and three internal degrees of freedom. Magnetic imaging on
lithographically-patterned permalloy nanostrips confirms these predictions and
shows that these DWs can be moved with an external magnetic field of about 1mT.
An extended phase diagram describing the regions of stability of all known
types of DWs in permalloy nanostrips is provided.Comment: 19 pages, 7 figure
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