260 research outputs found
A fast front-end electronics for the RPC detector in the HARP experiment
A fast 8-channel summing preamplifier and a 16-channel splitter for the readout of the resistive plate chambers in the HARP detector at the CERN Proton Synchrotron are presented. The on-chamber summing preamplifier has an equivalent input noise of less than 10 fC r.m.s., an amplification of 100 mV/pC and less than 1 ns peaking time. The splitter splits the signals from the summing preamplifier into a timing path and a charge path. In the timing path, the signal amplitude is further amplified by a factor of 10 and then discriminated at a 50 mV threshold. The time-over-threshold signal has an intrinsic time skew of less than 15 ps. The discriminator output is sent via twisted-pair cables to a commercial time-to-amplitude converter. In the charge path, the signal is also amplified and sent via twisted-pair cables to a commercial charge-to-amplitude converter
Polaris B, an optical companion of Polaris (alpha UMi) system: atmospheric parameters, chemical composition, distance and mass
We present an analysis of high-resolution spectroscopic observations of
Polaris B, the optical companion of the Polaris Ab system. The star has a
radial velocity V_r of -16.6km/s to -18.9km/s, and a projected rotational
velocity vsini=110 km/s. The derived atmospheric parameters are: Teff=6900K;
logg=4.3; V_t=2.5km/s. Polaris B has elemental abundances generally similar to
those of the Cepheid Polaris A (Usenko et al. 2005a), although carbon, sodium
and magnesium are close to the solar values. At a spectral type of F3V Polaris
B has a luminosity of 3.868L_sun, an absolute magnitude of +3.30mag, and a
distance of 109.5pc. The mass of the star is estimated to be 1.39M_sun, close
to a mass of 1.38+/-0.61M_sun for the recently-resolved orbital periods
companion Polaris Ab observed by Evans et al. (2007).Comment: 6 pages, 3 figures, 1 tabl
Контейнерные перевозки в глобальном рынке морской торговли
Усенко Е. А. Контейнерные перевозки в глобальном рынке морской торговли / Е. А. Усенко // Економіко-правовий розвиток сучасної України : матер. ІIІ Всеукр. наук. конф. студ., аспір. та молодих вчених (22-23 листопада 2013 р., м. Одеса) / за ред. д.е.н., проф. О. М. Кібік, д.ю.н., проф. О. П. Подцерковного ; Національн. ун-т «Одеська юридична академія» – Одеса : Фенікс, 2013. – С. 256-259
Revisiting the 'LSND anomaly' II: critique of the data analysis
This paper, together with a preceding paper, questions the so-called 'LSND
anomaly': a 3.8 sigma excess of antielectronneutrino interactions over standard
backgrounds, observed by the LSND Collaboration in a beam dump experiment with
800 MeV protons. That excess has been interpreted as evidence for the
antimuonneutrino to antielectronneutrino oscillation in the \Deltam2 range from
0.2 eV2 to 2 eV2. Such a \Deltam2 range is incompatible with the widely
accepted model of oscillations between three light neutrino species and would
require the existence of at least one light 'sterile' neutrino. In a preceding
paper, it was concluded that the estimates of standard backgrounds must be
significantly increased. In this paper, the LSND Collaboration's estimate of
the number of antielectronneutrino interactions followed by neutron capture,
and of its error, is questioned. The overall conclusion is that the
significance of the 'LSND anomaly' is not larger than 2.3 sigma.Comment: 30 pages, 16 figures, 6 table
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