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31.
Using a streak camera we have measured the three Stokes polarization parameters during a polarization switch of a vertical-cavity semiconductor laser. The switch occurs along a corkscrew path on the Poincare sphere and takes on average a few nanoseconds; this value agrees with a theoretical treatment based upon the Fokker-Planck equation. 相似文献
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Fabrizio Forghieri Alberto Bononi Jian-Guo Zhang Paul R. Prucnal Giorgio Picchi Giancarlo Prati 《Fiber and Integrated Optics》2013,32(2):165-183
Abstract Some recent results on all-optical packet-switching and broadcasting networks are presented. The performance evaluation problem of packet-switching transparent optical networks with deflection routing is addressed. Transmission error arguments show how, for a given optical bit rate, the size of an all-optical nonregenerative multishop network is limited by the accumulation of noise and distortion in the optical fiber channel. Time-domain multiple access techniques are exploited in novel architectures based on recently proposed all-optical sampling gates to realize the matching of the ultrahigh optical speed allowed by the large bandwidth of the fiber with the lower speed of the electronic components needed at the user ends. These architectures allow great simplification of the node structure in the considered all-optical multihop and broadcast networks. 相似文献
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Gilberto Batista de Souza Ana Rita A. Nogueira Vitor R. Del-Santo Cristina Maria C. Picchi Edílson S. Guimarães Waldomiro Barioni Jr 《Accreditation and quality assurance》2009,14(8-9):455-460
The Embrapa Cattle-Southeast research unit conducts a program to compare the results provided by laboratories that perform animal feed analyses. Fifty-two laboratories, representing all the Brazilian regions, have participated in the program. The assays included are those normally carried out by animal nutrition laboratories on animal feed and mineral supplements, a total of 22 different analyses. Four rounds of the program are performed annually. Each package provided to the laboratories for testing contains three kinds of animal feed (three each of forage and commercial feed), along with three mineral supplements. For the evaluation of assigned values and standard deviation, the median and robust standard deviation of the participants’ results are used. This paper reports the experience in coordinating the Brazilian interlaboratory comparison exercise. 相似文献
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M. Aglietta P. Antonioli G. Badino M. Bertaina R. Bertoni A. Castellina A. Chiavassa W. Fulgione P. Galeotti P. Ghia A. Giuliano R. Granella C. Melagrana C. Morello G. Navarra L. Panaro L. Periale P. Picchi O. Saavedra G. C. Trinchero P. Vallania S. Vernetto C. Vigorito 《Il Nuovo Cimento C》1995,18(6):629-645
Summary The Large-Volume Detector (LVD) in the Gran Sasso underground Laboratory is a multipurpose detector consisting of a large
volume of liquid scintillator (at present 562 tons are in data taking) interleaved with limited-streamer tubes. Several physical
problems are investigated with LVD, the major being the search for neutrino bursts from gravitational stellar collapses in
our Galaxy. In this paper we discuss some results on cosmic neutrinos and cosmic-ray muons obtained with the first of the
five towers of LVD (operational since June 1992) and part of the second tower (operational since June 1994). The results of
the search for supernovae neutrinos show that LVD is a neutrino observatory able to detect neutrinos of different flavours
from gravitational stellar collapses in all our Galaxy, over a wide range of burst durations. Indeed, the carbon-based liquid-scintillator
target gives a unique possibility to directly detect neutral- and charged-currents neutrino interactions with a very good
signature. This characteristic of LVD allows us to make an indirect estimate of the neutrino rest mass and of neutrino oscillations
from supernovae in our Galaxy. No evidence for burst candidates has been found in the data recorded from June 1992 to March
1995, for a total live time of 682 days and a total exposure of 613 tons per year. We present the results of a time coincidence
analysis between low-energy signals, eventually due to neutrinos of different flavours, and γ-ray bursts (GRBs) detected by
the BATSE experiment. This search covers the period from June 1993 to March 1995, during which 41 GRBs have been selected
from the BATSE data. Since no excess of events in LVD has been found, upper limits on the neutrino fluxes are reported for
(νe, p), and for neutral- and charged-currents neutrino interactions of different flavours with the C-nuclei of the scintillator.
The muon intensity as a function of slant depth is presented. These measurements, obtained during a live time period of 11.556
hours, cover a slant depths range from about 3000 to about 20 000 hg/cm2 of standard rock and extend over five decades of intensity. An interesting result is that the muon flux is independent of
slant depth beyond a depth of about 14 000 hg/cm2 of standard rock, and corresponds to near horizontal muons. This is direct evidence that this flux is due to atmospheric
neutrinos interacting in the rock surrounding LVD. 相似文献
36.
We have considered the influence of short-range dynamical and statistical correlations on the elastic and summed inelastic scattering of high-energy hadrons from light nuclei. Our calculations are based on the complete multiple scattering series of Glauber. The correlation effects are discussed on the example of the inelastic sum rule for p-16O scattering. 相似文献
37.
Fabrizio Forghieri Alberto Bononi Jian-Guo Zhang Paul R. Prucnal Giorgio Picchi Giancarlo Prati 《Fiber and Integrated Optics》1994,13(2):165-183
Some recent results on all-optical packet-switching and broadcasting networks are presented. The performance evaluation problem of packet-switching transparent optical networks with deflection routing is addressed. Transmission error arguments show how, for a given optical bit rate, the size of an all-optical nonregenerative multishop network is limited by the accumulation of noise and distortion in the optical fiber channel. Time-domain multiple access techniques are exploited in novel architectures based on recently proposed all-optical sampling gates to realize the matching of the ultrahigh optical speed allowed by the large bandwidth of the fiber with the lower speed of the electronic components needed at the user ends. These architectures allow great simplification of the node structure in the considered all-optical multihop and broadcast networks. 相似文献
38.
Bellotti R Cafagna F Circella M De Cataldo G De Marzo CN Giglietto N Spinelli P Golden RL Stephens SA Stochaj SJ Webber WR De Pascale MP Morselli A Picozza P Ormes JF Streitmatter RE Massimo Brancaccio F Papini P Piccardi P Spillantini P Basini G Bongiorno F Ricci M Brunetti MT Codino A Grimani C Menichelli M Salvatori I 《Physical review D: Particles and fields》1996,53(1):35-43
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