Search results for "spin"
showing 10 items of 5044 documents
Comparing proton momentum distributions in A = 2 and 3 nuclei via 2H 3H and 3He (e,e′p) measurements
2019
We report the first measurement of the $(e,e'p)$ reaction cross-section ratios for Helium-3 ($^3$He), Tritium ($^3$H), and Deuterium ($d$). The measurement covered a missing momentum range of $40 \le p_{miss} \le 550$ MeV$/c$, at large momentum transfer ($\langle Q^2 \rangle \approx 1.9$ (GeV$/c$)$^2$) and $x_B>1$, which minimized contributions from non quasi-elastic (QE) reaction mechanisms. The data is compared with plane-wave impulse approximation (PWIA) calculations using realistic spectral functions and momentum distributions. The measured and PWIA-calculated cross-section ratios for $^3$He$/d$ and $^3$H$/d$ extend to just above the typical nucleon Fermi-momentum ($k_F \approx 250$ …
High-spin states beyond the proton drip-line: Quasiparticle alignments in Cs-113
2015
Excited states have been studied in the deformed proton emitter 113Cs. Gamma-ray transitions have been unambiguously assigned to 113Cs by correlation with its characteristic proton decay, using the method of recoil-decay tagging. Two previously identified rotational bands have been observed and extended to tentative spins of 45/2 and 51/2 h¯, with excitation energies over 8 MeV above the lowest state. These are the highest angular momenta and excitation energies observed to date in any nucleus beyond the proton drip-line. Transitions in the bands have been rearranged compared to previous work. A study of aligned angular momenta, in comparison to the predictions of Woods–Saxon cranking calcu…
Vēlīnie rezultāti un pacienta apmierinatība pēc ceļa locītavas endoprotezēšanas, atkarībā no pielietotās anestēzijas veida
2016
Starp pacientiem pasaulē, kam veikta totāla ceļa locītavas endoprotezēšana, pēc operācijas līdz pat 30% neizjūt nekādus sāpju vai funkcionalitātes uzlabojumus. Daļa pacientu izjūt smagas sāpes pēcoperācijas periodā un daudziem tās saglabājas vēl gadu pēc operācijas. Pētījuma mērķis ir noskaidrot kurš anestēzijas veids: kombinētā spināli epidurālā (KSEA) vai spinālā anestēzija kombinēta ar nervus femoralis katetru (SA+NF), ir saistīts ar viszemākām sāpēm pēcoperācijas periodā, apmēram gadu pēc operācijas un ar vislabāko ceļa locītavas funkcionalitāti, pēc paša pacienta vērtējuma. Otrs mērķis ir identificēt iespējamos riska faktorus, kuru dēļ pacientam var būt neapmierinoši operācijas iznākum…
Selective writing and read-out of a register of static qubits
2013
We propose a setup comprising an arbitrarily large array of static qubits (SQs), which interact with a flying qubit (FQ). The SQs work as a quantum register, which can be written or read-out by means of the FQ through quantum state transfer (QST). The entire system, including the FQ's motional degrees of freedom, behaves quantum mechanically. We demonstrate a strategy allowing for selective QST between the FQ and a single SQ chosen from the register. This is achieved through a perfect mirror located beyond the SQs and suitable modulation of the inter-SQ distances.
Superconducting tunnel junction fabrication on three-dimensional topography based on direct laser writing
2020
Superconducting junctions are widely used in a multitude of applications ranging from quantum information science and sensing to solidstate cooling. Traditionally, such devices must be fabricated on flat substrates using standard lithographic techniques. In this study, we demonstrate a highly versatile method that allows for superconducting junctions to be fabricated on a more complex topography. It is based on maskless direct laser writing and two-photon lithography, which allows writing in 3D space. We show that high-quality normal metal–insulator–superconductor tunnel junctions can be fabricated on top of a 20-lm-tall three-dimensional topography. Combined with conformal resist coating m…
Superradiant Quantum Phase Transition for an Exactly Solvable Two-Qubit Spin-Boson Model
2023
A spin-boson-like model with two interacting qubits is analysed. The model turns out to be exactly solvable since it is characterized by the exchange symmetry between the two spins. The explicit expressions of eigenstates and eigenenergies make it possible to analytically unveil the occurrence of first-order quantum phase transitions. The latter are physically relevant since they are characterized by abrupt changes in the two-spin subsystem concurrence, in the net spin magnetization and in the mean photon number.
Transport and extraction of radioactive ions stopped in superfluid helium
2003
A new approach to convert a high energy beam to a low energy one, which is essential for the next generation radioactive ion beam facilities, has been proposed and tested at Jyvaskyla, Finland. An open Ra-223 alpha-decay-recoil source has been used to produce radioactive ions in superfluid helium. The alpha spectra demonstrate that the recoiling Rn-219 ions have been extracted out of liquid helium. This first observation of the extraction of heavy positive ions across the superfluid helium surface was possible thanks to the high sensitivity of radioactivity detection. An efficiency of 36% was obtained for the ion extraction out of liquid helium. (C) 2003 Elsevier Science B.V. All rights res…
Diritti respinti. Particolari conseguenze del razzismo istituzionale in Italia
2011
Estudio de la vía visual mediante tomografía de coherencia óptica y resonancia magnética cerebral y medular para la formulación y validación de model…
2020
Estudiar la correlación entre valores de tomografía de coherencia óptica (OCT, Optical Coherence Tomography) peripapilar y macular con volumetrías cerebrales y espinales determinadas a partir de imágenes de resonancia magnética (RM), teniendo en cuenta el tipo de esclerosis múltiple (EM) y el antecedente de neuritis óptica (NO). Formular y validar modelos matemáticos para la predicción de la discromatopsia y de la discapacidad a partir de marcadores clínicos y paraclínicos. MATERIAL Y MÉTODO: Estudio observacional, analítico y transversal de 92 pacientes de la Unidad Mixta de EM y Neurorregeneración del Hospital Universitario y Politécnico La Fe de Valencia. De cada paciente se recogieron l…
Rakennusten koristemaalausten restaurointi
2017
Maisterin tutkielmassani tarkastelen koristemaalattujen rakennuspintojen restauroinnin ilmiötä ja sen kehittymistä nykyiseen muotoonsa. Rakennuspintojen restaurointi sisältää erilaisia toimia konservoinnista uusien osien toteuttamiseen sisältäen myös rekonstruoinnin. Tutkimuksen tavoitteena on selvittää, miten rakennussuojelun arvotaustan muodostuminen liittyy näihin restaurointitoimenpiteisiin ja miten rakennuspitojen restaurointi on muuttunut 1960-luvulta alkaen. Arvotaustan muodostumisen selvittämiseksi tutkin kulttuuriperinnön suojelua koskevia kansainvälisiä peruskirjoja, rakennussuojelun normeja ja niihin liittyvää kirjallisuutta. Empiirisen osan aineistona on pääkaupunkiseudulla toim…