171 research outputs found
Generalized contour deformation method in momentum space: two-body spectral structures and scattering amplitudes
A generalized contour deformation method (GCDM) which combines complex
rotation and translation in momentum space, is discussed. GCDM gives accurate
results for bound, virtual (antibound), resonant and scattering states starting
with a realistic nucleon-nucleon interaction. It provides a basis for full
off-shell -matrix calculations both for real and complex input energies.
Results for both spectral structures and scattering amplitudes compare
perfectly well with exact values for the separable Yamaguchi potential.
Accurate calculation of virtual states in the Malfliet-Tjon and the realistic
CD-Bonn nucleon-nucleon interactions are presented.
GCDM is also a promising method for the computation of in-medium properties
such as the resummation of particle-particle and particle-hole diagrams in
infinite nuclear matter. Implications for in-medium scattering are discussed.Comment: 15 pages, revte
Exploring manifestation and nature of a dineutron in two-neutron emission using a dynamical dineutron model
Emission of two neutrons or two protons in reactions and decays is often
discussed in terms of "dineutron" or "diproton" emission. The discussion often
leans intuitively on something described by Migdal-Watson approximation. In
this work we propose a way to formalize situations of dineutron emission. It is
demonstrated that properly formally defined dineutron emission may reveal
properties which are drastically different from those traditionally expected,
and properties which are actually observed in three-body decays.Comment: 11 pages, 11 Figure
Exploring the relationship between working memory deficits and reading difficulties
This study explored the relationship between working memory (WM) deficits and reading difficulties using secondary data analysis on data collected from 63 English speaking students in two urban school divisions in Saskatchewan participating in a larger SSHRC funded study (Marche, McIntyre, Claypool, 2013). First, this study addressed whether the WM profiles of individuals with reading difficulties were different from those of individuals without reading difficulties. The results showed that individuals with reading difficulties scored lower than individuals with average reading ability on measures of verbal short-term memory (STM), verbal WM, and visuospatial WM. Second, this study looked at the differential effects of computer-based WM training on the WM profiles of children with and without reading difficulties. The results showed that after WM training, there was a difference between the visuospatial STM scores of individuals with and without difficulties, when reading ability was determined by the combination of a decoding and comprehension task. Furthermore, a difference was also noted between the visuospatial WM scores of individuals with and without word decoding difficulties, and the visuospatial STM, verbal WM, and visuospatial WM scores of individuals with and without reading comprehension difficulties. Additionally, the verbal STM scores of individuals with reading comprehension difficulties were marginally different than the scores of individuals without. No differences were found between individuals who did not participate in WM training. The limitations of the study, as well as the implications for practice and future research, are discussed
Closed-shell properties of O with {\em ab initio} coupled-cluster theory
We present an \emph{ab initio} calculation of spectroscopic factors for
neutron and proton removal from O using the coupled-cluster method and a
state-of-the-art chiral nucleon-nucleon interaction at
next-to-next-to-next-to-leading order. In order to account for the coupling to
the scattering continuum we use a Berggren single-particle basis that treats
bound, resonant, and continuum states on an equal footing. We report neutron
removal spectroscopic factors for the O states ,
, and , and proton removal spectroscopic factors for the
N states and . Our calculations support the accumulated
experimental evidence that O is a closed-shell nucleus.Comment: 5 pages, 2 figures, 1 tabl
How Open is Open Internet?
US Vice President Joe Biden and UK Foreign Secretary William Hague both made statements in support of the “open internet” at the London Conference on Cyberspace, but what does “open” really mean? Already under discussion are limitations to “openness” in the name of copyright protection and national security, and the debate has focused largely on consumer’s rights to access. There is another angle to be considered, which concerns access for those providing online content. Should content providers pay to be online, or should they be allowed to pay for preferential service? Recently, UK content providers weighed in on the debate
Computation of spectroscopic factors with the coupled-cluster method
We present a calculation of spectroscopic factors within coupled-cluster
theory. Our derivation of algebraic equations for the one-body overlap
functions are based on coupled-cluster equation-of-motion solutions for the
ground and excited states of the doubly magic nucleus with mass number and
the odd-mass neighbor with mass . As a proof-of-principle calculation, we
consider O and the odd neighbors O and N, and compute the
spectroscopic factor for nucleon removal from O. We employ a
renormalized low-momentum interaction of the type derived
from a chiral interaction at next-to-next-to-next-to-leading order. We study
the sensitivity of our results by variation of the momentum cutoff, and then
discuss the treatment of the center of mass.Comment: 8 pages, 6 figures, 3 table
Analyzing the didactic potential of videos appealing to emotions in the Social studies’ English classroom in upper secondary school
Læring oppstår i møte med ulike tekstformer frå ulike typar medium, og i det 21. århundret er det særskilt dei multimodale tekstane som blir brukt i engelskundervisninga. Denne masteroppgåva fokuserte på programfaget samfunnsfagleg engelsk. Føremålet med dette studiet i engelsk fagdidaktikk var å sjå nærare på det didaktiske potensiale av videoar som multimodale tekstar som omhandlar kontroversielle tema og appellerer til sjåarane sine kjensler. Den nye overordna delen til læreplanen (som trer i kraft i 2020) legg blant anna vekt på kritisk tenking og etisk medvit. Sjølv om videoar er eit mykje brukt medium i engelskundervisninga i Noreg, har framandspråksdidaktikken fokusert lite på det didaktiske potensiale av videoar som multimodale tekstar. I forhold til læring og kommunikasjon, og om kritisk tenking og etisk medvit er også desse sidene i engelsk fagdidaktikk i liten grad blitt undersøkt i samband med analyse av videoar. Målet med studiet var å utforska korleis videoar som multimodale tekstar skaper meining og appellerer til kjensler, og for å presentere kontroversielle tema i det norske klasserommet. Studiet har vidare hatt som mål å analysera det større potensiale av videoar i undervisninga, samt korleis bruken av ein multimodal tilnærming til materialet kan fremja danning. Studiet har brukt ein kvalitativ metode der den multimodal analysen illustrerer og diskuterer korleis ei multimodal tilnærming kan vera nyttig når ein underviser om kontroversielle tema som appellerer til kjensler. Det empiriske materialet er sett saman av ulike analyseutdrag av to videoar som omhandlar to forskjellige kontroversielle tema i USA og Storbritannia. Den multimodale analysen som vart brukt for å analysera det didaktiske potensiale av videoane fokuserte på sosialsemiotikk og meiningsdanning, kombinert med retorisk analyse som fokuserte på Aristoteles sine retoriske bevismidlar (etos, logos og patos). Funna frå analysen indikerer at videoar som multimodale tekstar vil opna for refleksjon og diskusjon av kontroversielle tema. Den gjer og elevane meir medvitne om korleis og kvifor videoar som appellerer til kjensler påverkar oss som sjåarar. Det blir i denne masteroppgåva argumentert for at ei multimodal tilnærming til videoar i det engelske klasserommet er viktig for å utnytta det didaktiske potensiale av videoar. Vidare blir det også argumentert for at læring er tilgjengeleg i alle ulike former, og det blir til slutt presentert didaktiske tilrådingar og framlegg til vidare forsking.Engelsk mastergradsoppgaveMPENGLMAHF-ENGMAHF-LÆFRZMPHFFAKENG35
Decay mechanism and lifetime of Kr
The lifetime of the recently discovered emitter Kr was recently
found considerably below the lower limit predicted theoretically. This
communication addresses this issue.Different separation energy systematics are
analyzed and different mechanisms for emission are evaluated. It is found
that the most plausible reason for this disagreement is a decay mechanism of
Kr, which is not "true " emission, but "transition dynamics" on the
borderline between true and sequential decay mechanisms. If this is
true, this imposes stringent limits MeV on the ground state
energy of Br relative to the Se- threshold.Comment: 7 pages, 8 figure
Valkude uuringute algoritm monoklonaalsete gammopaatiate korral
Eesti Arst 2023; 102(6–7):359–36
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