The C49-C54 transformation has been studied in TiSi(2) thin films having different concentration of defects. The defect concentration in the C49 phase has been varied using different thermal ...processes in the 460-540 deg C temperature range; in fact, the defect concentration decreases with increasing the temperature and/or the duration of the thermal process as attested by the large variation of the silicide residual resistivity at 4 K. The kinetics of the transformation at 650 deg C has been followed by in situ resistivity measurements and, for each sample, the transition time decreases as the defect concentration in the metastable phase decreases.
The double polarization (beam-recoil) observables
and
have been measured for the reaction
p
→
K
+
from threshold production to
MeV. The data were obtained with the linearly polarized beam of the ...GRAAL facility. Values for the target asymmetry
T
could also be extracted despite the use of an unpolarized target. Analyses of our results by two isobar models tend to confirm the necessity to include new or poorly known resonances in the 1900MeV mass region.
The
beam asymmetry in the photoproduction of neutral pions from quasi-free nucleons in a deuteron target was measured for the first time between 0.60 and 1.50GeV, with the GRAAL polarized and tagged ...photon beam. The asymmetry values from the quasi-free proton were found equal to the ones extracted from a pure proton target. The asymmetries from quasi-free proton and quasi-free neutron were found equal up to 0.82GeV and substantially different at higher energies. The results are compared with recent partial-wave analyses.
When a Ta layer is deposited at the Si-Ti interface a new phase has been detected, i.e., the TiSi sub(2) C40. The C40-C54 transformation kinetics and the film morphology are consistent with an ...increase of the nucleation density with respect to the C49-C54 transition. The activation energies for the nucleation rate (4.2 plus or minus 0.3 eV) and the growth velocity (4.0 plus or minus 0.4 eV) have been obtained from the in situ sheet resistance and the transmission electron microscopy results. These results show that the process with a Ta layer at the Ti-Si interface has a greater scalability with respect to the standard TiSi sub(2) process. copyright 2002 Elsevier Science B.V. All rights reserved.
Compact solid-state detectors based on CVD single-crystal diamonds (SCD), configured in a p-type/intrinsic/Schottky-metal layered structure, are proposed for the detection of high-energy ions at the ...15-MV tandem accelerator of the Southern National Laboratory of INFN in Catania. The spectroscopic response of two thin-film SCD detectors has been studied by valying the angle of incidence of a 27-77 MeV ...-scattered ion beam and a simple theoretical model is reported for the fit of the experimental curves of the collected energy vs. the angle of incidence. A rough estimation of the detector sensitive thickness and of the charge collection efficiency has thus been obtained. (ProQuest: ... denotes formulae/symbols omitted.)
JETP Letters, 106, 693 (2017) Observation of a narrow structure at $W\sim 1.68$ GeV in the excitation
functions of some photon- and pion-induced reactions may signal a new narrow
isospin-1/2 ...$N(1685)$ resonance. New data on the $\gamma N \to \pi \eta N$
reactions from GRAAL seems to reveal the signals of both $N^+(1685)$ and
$N^0(1685)$ resonances.
JETP Letters, 105, 625 (2017) Different interpretations of narrow structures at $W\sim 1.68$ and $W\sim
1.72$ GeV observed in several reactions are discussed. It is questionable
whether interference ...phenomena could explain the whole complex of experimental
findings. More probable hypotheses would be the existence of one or two narrow
resonances $N(1685)$ and $N(1726)$ and/or the sub-threshold virtual $K\Sigma$
and $\omega p$ production (cusps).
The effect of a thin Ta layer at the Ti/Si interface on the kinetics of the C49-C54 transition is reported. The transformation kinetics were monitored in detail by in situ sheet resistance ...measurements, which, coupled to structural characterization, allowed us to evidence the presence of an intermediate phase before C54 formation. The temperature at which the C54 phase is formed decreases at a Ta concentration of 4.5 mult 10 exp 15 cm exp -2 . mu -Raman images of partially transformed samples indicates that the density of C54 grains in the presence of Ta is about one order of magnitude higher with respect to pure Ti/Si samples.
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