Search results for "Proton"
showing 10 items of 5886 documents
Hydrogen-related radiation defects in SiO2-based glasses
2008
Abstract Spectroscopic properties of hydrogen atom trapped in an oxygen vacancy in SiO2 glass were studied. Samples were loaded with D2 and H2 gases to convert O vacancies to pairs of Si–D and Si–H groups, and subsequently irradiated by F2 laser in order to destroy some of these groups. Electron paramagnetic resonance, infrared absorption and visible/UV absorption spectra were measured. Proton hyperfine doublet with splitting of 1.05 mT was found in all H2-treated/irradiated samples. UV-bleaching treatment showed that this signal is independent of the other, well-known hydrogen-related signals in silica. The size of the hyperfine splitting corresponds to twice the 1H nuclear Zeeman splittin…
Measurements of forward proton production with incident protons and charged pions on nuclear targets at the CERN Proton Synchroton
2010
Measurements of the double-differential proton production cross-section d(2 sigma)/dpd Omega in the range of momentum 0.5 GeV/c <= p < 8.0 GeV/c and angle 0.05 rad <= theta < 0.25 rad in collisions of charged pions and protons on beryllium, carbon, aluminium, copper, tin, tantalum, and lead are presented. The data were taken with the large acceptance HARP detector in the T9 beam line of the CERN Proton Synchrotron. Incident particles were identified by an elaborate system of beam detectors and impinged on a target of 5% of a nuclear interaction length. The tracking and identification of the produced particles was performed using the forward spectrometer of the HARP experiment. Results are o…
Properties of nuclei in the nobelium region studied within the covariant, Skyrme, and Gogny energy density functionals
2015
We calculate properties of the ground and excited states of nuclei in the nobelium region for proton and neutron numbers of 92 <= Z <= 104 and 144 <= N <= 156, respectively. We use three different energy-density-functional (EDF) approaches, based on covariant, Skyrme, and Gogny functionals, each within two different parameter sets. A comparative analysis of the results obtained for odd-even mass staggerings, quasiparticle spectra, and moments of inertia allows us to identify single-particle and shell effects that are characteristic to these different models and to illustrate possible systematic uncertainties related to using the EDF modelling
Proton decay of 108I and its significance for the termination of the astrophysical rp-process
2019
Abstract Employing the Argonne Fragment Mass Analyzer and the implantation-decay-decay correlation technique, a weak 0.50(21)% proton decay branch was identified in 108I for the first time. The 108I proton-decay width is consistent with a hindered l = 2 emission, suggesting a d 5 2 origin. Using the extracted 108I proton-decay Q value of 597(13) keV, and the Q α values of the 108I and 107Te isotopes, a proton-decay Q value of 510(20) keV for 104Sb was deduced. Similarly to the 112,113Cs proton-emitter pair, the Q p ( I 108 ) value is lower than that for the less-exotic neighbor 109I, possibly due to enhanced proton-neutron interactions in N ≈ Z nuclei. In contrast, the present Q p ( Sb 104 …
The electronion scattering experiment ELISe at the International Facility for Antiproton and Ion Research (FAIR) - A conceptual design study
2011
The electronion scattering experiment ELISe is part of the installations envisaged at the new experimental storage ring at the International Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. It offers an unique opportunity to use electrons as probe in investigations of the structure of exotic nuclei. The conceptual design and the scientific challenges of ELISe are presented. © 2011 Elsevier B.V. All rights reserved.
Direct photon production at low transverse momentum in proton-proton collisions at √s = 2.76 and 8 TeV
2019
Measurements of inclusive and direct photon production at midrapidity in pp collisions at √s=2.76 and 8 TeV are presented by the ALICE experiment at the LHC. The results are reported in transverse momentum ranges of 0.47 GeV/c is at least one σ above unity and consistent with expectations from next-to-leading order pQCD calculations. peerReviewed
Multiplicity dependence of light-flavor hadron production in pp collisions at √s = 7 TeV
2019
Comprehensive results on the production of unidentified charged particles, π±, K±, K0S, K∗(892)0, p, ¯p, ϕ(1020), Λ, ¯¯¯Λ, Ξ−, ¯¯¯Ξ+, Ω−, and ¯¯¯Ω+ hadrons in proton-proton (pp) collisions at √s=7 TeV at midrapidity (|y|<0.5) as a function of charged-particle multiplicity density are presented. In order to avoid autocorrelation biases, the actual transverse momentum (pT) spectra of the particles under study and the event activity are measured in different rapidity windows. In the highest multiplicity class, the charged-particle density reaches about 3.5 times the value measured in inelastic collisions. While the yield of protons normalized to pions remains approximately constant as a functi…
Jet-like correlations with neutral pion triggers in pp and central Pb–Pb collisions at 2.76 TeV
2016
We present measurements of two-particle correlations with neutral pion trigger particles of transverse momenta 8>pT trig>16 GeV/c and associated charged particles of 0.5>pT assoc>10 GeV/c versus the azimuthal angle difference Δφ at midrapidity in pp and central Pb–Pb collisions at √sNN=2.76 TeV with ALICE. The new measurements exploit associated charged hadrons down to 0.5 GeV/c, which significantly extends our previous measurement that only used charged hadrons above 3 GeV/c. After subtracting the contributions of the flow background, v2 to v5, the per-trigger yields are extracted for |Δφ|>0.7 on the near and for |Δφ−π|>1.1 on the away side. The ratio of per-trigger yields in Pb–Pb to thos…
0.1-10 MeV Neutron Soft Error Rate in Accelerator and Atmospheric Environments
2021
Neutrons with energies between 0.1-10 MeV can significantly impact the Soft Error Rate (SER) in SRAMs manufactured in scaled technologies, with respect to high-energy neutrons. Their contribution is evaluated in accelerator, ground level and avionic (12 km of altitude) environments. Experimental cross sections were measured with monoenergetic neutrons from 144 keV to 17 MeV, and results benchmarked with Monte Carlo simulations. It was found that even 144 keV neutrons can induce upsets due to elastic scattering. Moreover, neutrons in the 0.1-10 MeV energy range can induce more than 60% of the overall upset rate in accelerator applications, while their contribution can exceed 18% in avionics.…
Assessment of Proton Direct Ionization for the Radiation Hardness Assurance of Deep Submicron SRAMs Used in Space Applications
2021
Proton direct ionization from low-energy protons has been shown to have a potentially significant impact on the accuracy of prediction methods used to calculate the upset rates of memory devices in space applications for state-of-the-art deep sub-micron technologies. The general approach nowadays is to consider a safety margin to apply over the upset rate computed from high-energy proton and heavy ion experimental data. The data reported here present a challenge to this approach. Different upset rate prediction methods are used and compared in order to establish the impact of proton direct ionization on the total upset rate. No matter the method employed the findings suggest that proton dir…