Search results for "Elastic"
showing 10 items of 2162 documents
Transition form factors of the N(*()1535) as a dynamically generated resonance
2007
We discuss how electromagnetic properties provide useful tests of the nature of resonances, and we study these properties for the N*(1535) which appears dynamically generated from the strong interaction of mesons and baryons. Within this coupled channel chiral unitary approach, we evaluate the A_1/2 and S_1/2 helicity amplitudes as a function of Q^2 for the electromagnetic N*(1535) to gamma* N transition. Within the same formalism we evaluate the cross section for the reactions gamma N to eta N. We find a fair agreement for the absolute values of the transition amplitudes, as well as for the Q^2 dependence of the amplitudes, within theoretical and experimental uncertainties discussed in the…
The importance of kinematic twists and genuine saturation effects in dijet production at the Electron-Ion Collider
2021
We compute the differential yield for quark anti-quark dijet production in high-energy electron-proton and electron-nucleus collisions at small $x$ as a function of the relative momentum $\boldsymbol{P}_\perp$ and momentum imbalance $\boldsymbol{k}_\perp$ of the dijet system for different photon virtualities $Q^2$, and study the elliptic and quadrangular anisotropies in the relative angle between $\boldsymbol{P}_\perp$ and $\boldsymbol{k}_\perp$. We review and extend the analysis in [1], which compared the results of the Color Glass Condensate (CGC) with those obtained using the transverse momentum dependent (TMD) framework. In particular, we include in our comparison the improved TMD (ITMD…
Mössbauer investigations on glass-forming organic liquids
1992
Glycerol forms a molecular glass near 180K. Fe2+ dissolved in glycerol allows the study of the dynamics of the system by Mossbauer spectroscopy. Recently it has been shown that the Mossbauer spectra can be understood in a way consistent with the results of dielectric and ultrasonic viscoelastic relaxation measurements. A jump diffusion model of Sinqwi and Sjolander with a jump rate distribution according to Davidson and Cole allowed us to fit the Mossbauer spectra of Fe in glycerol. First attempts to compare mode coupling theory with Mossbauer spectra are reported.
Study of the electromagnetic background in the XENON100 experiment
2011
The XENON100 experiment, located at the Laboratori Nazionali del Gran Sasso (LNGS), aims to directly detect dark matter in the form of Weakly Interacting Massive Particles (WIMPs) via their elastic scattering off xenon nuclei. We present a comprehensive study of the predicted electronic recoil background coming from radioactive decays inside the detector and shield materials, and intrinsic contamination. Based on GEANT4 Monte Carlo simulations using a detailed geometry together with the measured radioactivity of all detector components, we predict an electronic recoil background in the WIMP-search energy range (0-100 keV) in the 30 kg fiducial mass of less than 10e-2 events/(kg-day-keV), co…
Measurement of high energy resolution inelastic proton scattering at and close to zero degrees
2009
13 pages, 15 figures.-- Printed version published Jul 1, 2009.
Ion-sputtering deposition of Ca–P–O films for microscopic imaging of osteoblast cells
2007
Abstract An ion-beam sputtering technique was used to produce Ca–P–O films on borosilicate glass at room temperature from hydroxyapatite targets using nitrogen, argon and krypton beams at different acceleration voltages. The sputtering target was pressed from high purity hydroxyapatite powder or mixture of high purity hydroxyapatite powder and red phosphorus in order to optimise the film composition. The film composition, determined using time-of-flight elastic recoil detection analysis (TOF–ERDA), was found to be strongly dependent on the ion energy used for deposition. By extra doping of the target with P the correct Ca/P atomic ratio in the deposited films was reached. The films deposite…
A study of solar thermal absorber stack based on CrAlSiNx/CrAlSiNxOy structure by ion beams
2019
Renewable energies are foreseen as a major energy resource for next generations. Among several energy sources and technologies available, Concentrated Solar Power (CSP) technology has a great potential, but it needs to be optimised, in particular to reduce the costs, with an increase of the operating temperature and long term stability. This goal can be achieved by tailoring the composition and multilayer structure of films. In this work we present and discuss the results obtained from solar absorber coatings based on nitride/oxynitride structures. A four-layer film structure, W/CrAlSiNx(HA)/CrAlSiNxOy(LA)/SiAlOx, was deposited on stainless steel substrates using magnetron sputtering deposi…
Characterization of ALD grown Ti x Al y N and Ti x Al y C thin films
2017
Abstract Atomic layer deposition (ALD) was used to grow Ti x Al y N and Ti x Al y C thin films using trimethylaluminum (TMA), titanium tetrachloride and ammonia as precursors. Deposition temperature was varied between 325 °C and 500 °C. Films were also annealed in vacuum and N 2 -atmosphere at 600–1000 °C. Wide range of characterization methods was used including time-of-flight elastic recoil detection analysis (ToF-ERDA), X-ray diffractometry (XRD), X-ray reflectometry (XRR), Raman spectroscopy, ellipsometry, helium ion microscopy (HIM), atomic force microscopy (AFM) and 4-point probe measurement for resistivity. Deposited films were roughly 100 nm thick and contained mainly desired elemen…
Ordering effects in extreme high-resolution depth profiling with MeV ion beams
2012
Abstract The continuing development of depth profiling with MeV ion beam methods with depth resolutions in the nanometre, and even sub-nanometre, regime implies the resolved depth become comparable with the interatomic spacing. To investigate how short-range ordering influences depth profiles at these resolutions, we have employed a mathematical modelling approach. The radial, g ( r ) and depth distribution, g ( z ) functions were calculated for (1 0 0) surface, random and amorphous Si structures at 300 K produced using molecular dynamics simulations with the EDIP quasi-empirical potential. The results showed that short-range ordering lead to reduction of the scattering yield below the deep…
Low-energy heavy-ion TOF-ERDA setup for quantitative depth profiling of thin films
2008
Abstract Low-energy heavy-ion time-of-flight elastic recoil detection analysis (TOF-ERDA) is becoming a mature technique for accurate characterization of thin films. In combination with a small tandem accelerator (∼2 MV terminal voltage) and beam energies below 20 MeV, it is suitable for routine analysis of key materials in semiconductor technology. In this paper we discuss advantages and drawbacks of low-energy ERDA, compared to high-energy ERDA, in terms of depth and mass resolution, detection efficiency for light elements, sample irradiation damage and quantification accuracy. The results presented are obtained with the time-of-flight telescope recently developed at IMEC. The time-of-fli…