667 research outputs found
Present and Future Gamma-Ray Probes of the Cygnus OB2 Environment
The MAGIC Collaboration has provided new observational data pertaining to the
TeV J2032+4130 gamma-ray source (within the Cygnus OB2 region), for energies
E_gamma >400 GeV. It is then appropriate to update the impact of these data on
gamma-ray production mechanisms in stellar associations. We consider two
mechanisms of gamma-ray emission, pion production and decay (PION) and
photo-excitation of high-energy nuclei followed by prompt photo-emission from
the daughter nuclei (A*). We find that while the data can be accommodated with
either scenario, the A* features a spectral bump, corresponding to the
threshold for exciting the Giant Dipole Resonance, which can serve to
discriminate between them. We comment on neutrino emission and detection from
the region if the PION and/or A* processes are operative. We also touch on the
implications for this analysis of future Fermi and Cerenkov Telescope Array
data.Comment: 6 pp, 2 figs. Matching version publihed in Phys. Rev.
The Capacitive Magnetic Field Sensor
The results of a study of sensitive element magnetic field sensor are represented in this paper. The sensor is based on the change of the capacitance with an active dielectric (ferrofluid) due to the magnitude of magnetic field. To prepare the ferrofluid magnetic particles are used, which have a followingdispersion equal to 50 < [the empty set] <= 56, 45 < [the empty set] <= 50, 40 < [the empty set] <=45 and [the empty set] <= 40 micron of nanocrystalline alloy of brand 5BDSR. The dependence of the sensitivity of the capacitive element from the ferrofluid with different dispersion of magnetic particles is considered. The threshold of sensitivity and sensitivity of a measuring cell with ferrofluid by a magnetic field was determined. The experimental graphs of capacitance change of the magnitude of magnetic field are presented
Swift Highly Charged Ion Channelling
We review recent experimental and theoretical progress made in the scope of
swift highly charged ion channelling in crystals. The usefulness of such
studies is their ability to yield impact parameter information on charge
transfer processes, and also on some time related problems. We discuss the
cooling and heating phenomena at MeV/u energies, results obtained with
decelerated H-like ion beams at GSI and with ions having an excess of electrons
at GANIL, the superdensity effect along atomic strings and Resonant Coherent
Excitation.Comment: to be published in Journal of Physics
Photon angular distribution and nuclear-state alignment in nuclear excitation by electron capture
The alignment of nuclear states resonantly formed in nuclear excitation by
electron capture (NEEC) is studied by means of a density matrix technique. The
vibrational excitations of the nucleus are described by a collective model and
the electrons are treated in a relativistic framework. Formulas for the angular
distribution of photons emitted in the nuclear relaxation are derived. We
present numerical results for alignment parameters and photon angular
distributions for a number of heavy elements in the case of E2 nuclear
transitions. Our results are intended to help future experimental attempts to
discern NEEC from radiative recombination, which is the dominant competing
process
Working Group Report on the "TeV Particle Astrophysics and Physics Beyond the Standard Model"
This working group focused mainly on the complementarity among particle
physics and astrophysics. The analysis of data from both fields will better
constrain theoretical models. Much of the discussion focused on detecting dark
matter and susy particles, and on the potential of neutrino and gamma-ray
astrophysics for seeking or constraining new physics.Comment: Report on Working Group in the TeV Particle Astrophysics Workshop II
- Madison - Aug 200
Application of the magnetic fluid as a detector for changing the magnetic field
In article the possibility of use of magnetic fluid as a sensitive element for fixing of change of induction of magnetic field in space is considered. Importance of solvable tasks is connected with search of the perspective magnetic substances susceptible to weak magnetic field. The results of a study of the capacitive method for fixing the change in the magnetic field on the basis of a ferromagnetic liquid are presented. The formation of chain structures in the ferrofluid from magnetic particles under the influence of the applied magnetic field leads to a change in the capacitance of the plate condenser. This task has important practical value for development of a magnetosensitive sensor of change of magnetic field
Application of the magnetic fluid as a detector for changing the magnetic field
In article the possibility of use of magnetic fluid as a sensitive element for fixing of change of induction of magnetic field in space is considered. Importance of solvable tasks is connected with search of the perspective magnetic substances susceptible to weak magnetic field. The results of a study of the capacitive method for fixing the change in the magnetic field on the basis of a ferromagnetic liquid are presented. The formation of chain structures in the ferrofluid from magnetic particles under the influence of the applied magnetic field leads to a change in the capacitance of the plate condenser. This task has important practical value for development of a magnetosensitive sensor of change of magnetic field
Single flux quantum circuits with damping based on dissipative transmission lines
We propose and demonstrate the functioning of a special Rapid Single Flux
Quantum (RSFQ) circuit with frequency-dependent damping. This damping is
achieved by shunting individual Josephson junctions by pieces of open-ended RC
transmission lines. Our circuit includes a toggle flip-flop cell, Josephson
transmission lines transferring single flux quantum pulses to and from this
cell, as well as DC/SFQ and SFQ/DC converters. Due to the desired
frequency-dispersion in the RC line shunts which ensures sufficiently low noise
at low frequencies, such circuits are well-suited for integrating with the
flux/phase Josephson qubit and enable its efficient control.Comment: 6 pages incl. 6 figure
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