11,612 research outputs found
Science highlights from the Fermi Large Area Telescope
During its first three years of operation, the Fermi Gamma-ray Space
Telescope has provided an unprecedented view of the high energy gamma-ray sky,
and also performed direct measurements of the cosmic-ray leptons and searches
for signals from dark matter. In this paper we present a short overview of some
highlight results, shedding new light on the high-energy side of the Universe.Comment: Contribution to Les Rencontres de Physique de la Vall\'ee D'Aoste (La
Thuile, February 27-March 5 2011); 12 pages, 5 figure
Mass formula for T=0 and T=1 ground states of N=Z nuclei
An algebraic model is developed to calculate the T=0 and T=1 ground state
binding energies for N=Z nuclei. The method is tested in the sd shell and is
then extended to 28-50 shell which is currently the object of many experimental
studies.Comment: 5 figure
Increasing Performances of TCP Data Transfers Through Multiple Parallel Connections
Although Transmission Control Protocol (TCP) is a widely deployed and successful protocol, it shows some limitations in present-day environments. In particular, it is unable to exploit multiple (physical or logical) paths between two hosts. This paper presents PATTHEL, a session-layer solution designed for parallelizing stream data transfers. Parallelization is achieved by striping the data flow among multiple TCP channels. This solution does not require invasive changes to the networking stack and can be implemented entirely in user space. Moreover, it is flexible enough to suit several scenarios - e.g. it can be used to split a data transfer among multiple relays within a peer-to-peer overlay networ
Plasduino: An inexpensive, general-purpose data acquisition framework for educational experiments
Based on the Arduino development platform, plasduino is an opensource data acquisition framework specifically designed for educational physics experiments. The source code, schematics and documentation are in the public domain under a GPL license and the system, streamlined for low cost and ease of use, can be replicated on the scale of a typical didactic lab with minimal effort. We describe the basic architecture of the system and illustrate its potential with some real-life examples
Odd Parity Light Baryon Resonances
We use a consistent SU(6) extension of the meson-baryon chiral Lagrangian
within a coupled channel unitary approach in order to calculate the T-matrix
for meson-baryon scattering in s-wave. The building blocks of the scheme are
the pion and nucleon octets, the rho nonet and the Delta decuplet. We identify
poles in this unitary T-matrix and interpret them as resonances. We study here
the non exotic sectors with strangeness S=0,-1,-2,-3 and spin J=1/2, 3/2 and
5/2. Many of the poles generated can be associated with known N, Delta, Sigma,
Lambda and Xi resonances with negative parity. We show that most of the
low-lying three and four star odd parity baryon resonances with spin 1/2 and
3/2 can be related to multiplets of the spin-flavor symmetry group SU(6). This
study allows us to predict the spin-parity of the Xi(1620), Xi(1690), Xi(1950),
Xi(2250), Omega(2250) and Omega(2380) resonances, which have not been
determined experimentally yet.Comment: New appendix and references adde
Pressure induced magnetic phase separation in LaCaMnO manganite
The pressure dependence of the Curie temperature T in
LaCaMnO was determined by neutron diffraction up to 8
GPa, and compared with the metallization temperature T \cite{irprl}.
The behavior of the two temperatures appears similar over the whole pressure
range suggesting a key role of magnetic double exchange also in the pressure
regime where the superexchange interaction is dominant. Coexistence of
antiferromagnetic and ferromagnetic peaks at high pressure and low temperature
indicates a phase separated regime which is well reproduced with a dynamical
mean-field calculation for a simplified model. A new P-T phase diagram has been
proposed on the basis of the whole set of experimental data.Comment: 5 pages, 4 figure
Two Detector Reactor Neutrino Oscillation Experiment Kr2Det at Krasnoyarsk. Status Report
We consider status of the Kr2Det project aimed at sensitive searches for
neutrino oscillations in the atmospheric neutrino mass parameter region around
Dm2 ~ 3x10-3 eV2and at obtaining new information on the electron neutrino mass
structure (Ue3).Comment: 4 pages in pdf file. Talk presented at NANP-2001 International
Conference in Dubna, Russia, June 200
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