93 research outputs found
‘My favourite things to do’ and ‘my favourite people’: Exploring salient aspects of children’s self-concept
This study explores the potential of the ‘draw-and-write’ method for inviting children to communicate salient aspects of their self-concept. Irish primary school children aged 10–13 years drew and wrote about their favourite people and things to do (social and active self). Children drew and described many salient activities (39 in total) and people – including pets. Results suggest that widely used, adult-constructed self-esteem scales for children, while multidimensional, are limited, and that ‘draw-and-write’ is an effective multimodal method with which children can express their social and active self-concepts
Theory of output coupling for trapped fermionic atoms
We develop a dynamic theory of output coupling, for fermionic atoms initially
confined in a magnetic trap. We consider an exactly soluble one-dimensional
model, with a spatially localized delta-type coupling between the atoms in the
trap and a continuum of free-particle external modes. Two important special
cases are considered for the confinement potential: the infinite box and the
harmonic oscillator. We establish that in both cases a bound state of the
coupled system appears for any value of the coupling constant, implying that
the trap population does not vanish in the infinite-time limit. For weak
coupling, the energy spectrum of the outgoing beam exhibits peaks corresponding
to the initially occupied energy levels in the trap; the height of these peaks
increases with the energy. As the coupling gets stronger, the energy spectrum
is displaced towards dressed energies of the fermions in the trap. The
corresponding dressed states result from the coupling between the unperturbed
fermionic states in the trap, mediated by the coupling between these states and
the continuum. In the strong-coupling limit, there is a reinforcement of the
lowest-energy dressed mode, which contributes to the energy spectrum of the
outgoing beam more strongly than the other modes. This effect is especially
pronounced for the one-dimensional box, which indicates that the efficiency of
the mode-reinforcement mechanism depends on the steepness of the confinement
potential. In this case, a quasi-monochromatic anti-bunched atomic beam is
obtained. Results for a bosonic sample are also shown for comparison.Comment: 16 pages, 7 figures, added discussion on time-dependent spectral
distribution and corresponding figur
Follow-up of the Neutron Star Bearing Gravitational-wave Candidate Events S190425z and S190426c with MMT and SOAR
On 2019 April 25.346 and 26.640 UT the LIGO and Virgo gravitational wave (GW)
observatories announced the detection of the first candidate events in
Observing Run 3 that contain at least one neutron star. S190425z is a likely
binary neutron star (BNS) merger at Mpc, while S190426c is
possibly the first NS-BH merger ever detected, at Mpc,
although with marginal statistical significance. Here we report our optical
follow-up observations for both events using the MMT 6.5-m telescope, as well
as our spectroscopic follow-up of candidate counterparts (which turned out to
be unrelated) with the 4.1-m SOAR telescope. We compare to publicly reported
searches, explore the overall areal coverage and depth, and evaluate those in
relation to the optical/NIR kilonova emission from the BNS merger GW170817, to
theoretical kilonova models, and to short GRB afterglows. We find that for a
GW170817-like kilonova, the partial volume covered spans up to about 40% for
S190425z and 60% for S190426c. For an on-axis jet typical of short GRBs, the
search effective volume is larger, but such a configuration is expected in at
most a few percent of mergers. We further find that wide-field -ray and
X-ray limits rule out luminous on-axis SGRBs, for a large fraction of the
localization regions, although these searches are not sufficiently deep in the
context of the -ray emission from GW170817 or off-axis SGRB afterglows.
The results indicate that some optical follow-up searches are sufficiently deep
for counterpart identification to about 300 Mpc, but that localizations better
than 1000 deg are likely essential.Comment: The first six authors contributed equally to this wor
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Technology and Discourse: A Comparison of Face-to-face and Telephone Employment Interviews
Very little research has investigated the comparability of telephone and face-to-face employment interviews. This exploratory study investigated interviewers' questioning strategies and applicants' causal attributions produced during semi structured telephone and face-to-face graduate recruitment interviews (N=62). A total of 2044 causal attributions were extracted from verbatim transcripts of these 62 interviews. It was predicted that an absence of visual cues would lead applicants to produce, and interviewers to focus on, information that might reduce the comparative anonymity of telephone interviews. Results indicate that applicants produce more personal causal attributions in telephone interviews. Personal attributions are also associated with higher ratings in telephone, but not face-to-face interviews. In face-to-face interviews, applicants who attributed outcomes to more global causes received lower ratings. There was also a non-significant tendency for interviewers to ask more closed questions in telephone interviews. The implications of these findings for research and practice are discussed
Search for Lorentz and CPT violation using sidereal time dependence of neutrino flavor transitions over a short baseline
A class of extensions of the Standard Model allows Lorentz and CPT violations, which can be identified
by the observation of sidereal modulations in the neutrino interaction rate. A search for such modulations
was performed using the T2K on-axis near detector. Two complementary methods were used in this study,
both of which resulted in no evidence of a signal. Limits on associated Lorentz and CPT-violating terms
from the Standard Model extension have been derived by taking into account their correlations in this
model for the first time. These results imply such symmetry violations are suppressed by a factor of more
than 10 20 at the GeV scale
Operation and performance of the ATLAS semiconductor tracker
The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74±0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, δ-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations
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