4,441 research outputs found
Fusion excitation function revisited
We report on a comprehensive systematics of fusion-evaporation and/or
fusion-fission cross sections for a very large variety of systems over an
energy range 4-155 A.MeV. Scaled by the reaction cross sections, fusion cross
sections do not show a universal behavior valid for all systems although a high
degree of correlation is present when data are ordered by the system mass
asymmetry.For the rather light and close to mass-symmetric systems the main
characteristics of the complete and incomplete fusion excitation functions can
be precisely determined. Despite an evident lack of data above 15A.MeV for all
heavy systems the available data suggests that geometrical effects could
explain the persistence of incomplete fusion at incident energies as high as
155A.MeV.Comment: 8 pages, 5 figures, contribution to the NN2012 Proceeding
Recommended from our members
The Diderot meteorite: The second chassignite
The Diderot meteorite is a dunite discovered in Sahara. The martian origin is unambiguous and Diderot shares strong petrographical similarities with Chassigny
On the inequivalence of statistical ensembles
We investigate the relation between various statistical ensembles of finite
systems. If ensembles differ at the level of fluctuations of the order
parameter, we show that the equations of states can present major differences.
A sufficient condition for this inequivalence to survive at the thermodynamical
limit is worked out. If energy consists in a kinetic and a potential part, the
microcanonical ensemble does not converge towards the canonical ensemble when
the partial heat capacities per particle fulfill the relation
.Comment: 4 pages, 4 figure
Assessing cognitive insight in nonpsychiatric individuals and outpatients with schizophrenia in Taiwan: an investigation using the Beck Cognitive Insight Scale
<p>Abstract</p> <p>Background</p> <p>The Beck Cognitive Insight Scale (BCIS) was designed for the assessment of the cognitive processes involved in self-reflection and the ability to modify erroneous beliefs and misinterpretations. Studies investigating the factor structure of the BCIS have indicated a two-factor model in the psychotic population. The factor structure of the BCIS, however, has not received much consideration in the nonpsychiatric population. The present study examined the factor structure and validity of the BCIS and compared its scores between nonpsychiatric individuals and outpatients with psychosis.</p> <p>Method</p> <p>The Taiwanese version of the BCIS was administered to 507 nonpsychiatric individuals and 118 outpatients with schizophrenia. The psychometric properties of the BCIS were examined through the following analyses: exploratory and confirmatory factor analyses, reliability, correlation analyses, and discriminative validity.</p> <p>Results</p> <p>The BCIS showed adequate internal consistency and stability over time. Exploratory and confirmatory factor analyses on the 15-item measure indicated a two-factor solution that supported the two dimensions of the Taiwanese BCIS, which was also observed with the original BCIS. Following the construct validation, we obtained a composite index (self-reflectiveness minus self-certainty) of the Taiwanese BCIS that reflected cognitive insight. Consistent with previous studies, our results indicated that psychosis is associated with low self-reflectiveness and high self-certainty, which possibly reflect lower cognitive insight. Our results also showed that better cognitive insight is related to worse depression in patients with schizophrenia spectrum disorders, but not in nonpsychiatric individuals. The receiver operating characteristic (ROC) analyses revealed that the area under the curve (AUC) was 0.731. A composite index of 3 was a good limit, with a sensitivity of 87% and a specificity of 51%.</p> <p>Conclusion</p> <p>The BCIS proved to be useful for measuring cognitive insight in Taiwanese nonpsychiatric and psychotic populations.</p
Antimatter and Matter Production in Heavy Ion Collisions at CERN (The NEWMASS Experiment NA52)
Besides the dedicated search for strangelets NA52 measures light
(anti)particle and (anti)nuclei production over a wide range of rapidity.
Compared to previous runs the statistics has been increased in the 1998 run by
more than one order of magnitude for negatively charged objects at different
spectrometer rigidities. Together with previous data taking at a rigidity of
-20 GeV/c we obtained 10^6 antiprotons 10^3 antideuterons and two antihelium3
without centrality requirements. We measured nuclei and antinuclei
(p,d,antiprotons, antideuterons) near midrapidity covering an impact parameter
range of b=2-12 fm. Our results strongly indicate that nuclei and antinuclei
are mainly produced via the coalescence mechanism. However the centrality
dependence of the antibaryon to baryon ratios show that antibaryons are
diminished due to annihilation and breakup reactions in the hadron dense
environment. The volume of the particle source extracted from coalescence
models agrees with results from pion interferometry for an expanding source.
The chemical and thermal freeze-out of nuclei and antinuclei appear to coincide
with each other and with the thermal freeze-out of hadrons.Comment: 12 pages, 8 figures, to appear in the proceedings of the conference
on 'Fundamental Issues in Elementary Matter' Bad Honnef, Germany, Sept.
25-29, 200
Diffusion Process in a Flow
We establish circumstances under which the dispersion of passive contaminants
in a forced, deterministic or random, flow can be consistently interpreted as a
Markovian diffusion process. In case of conservative forcing the repulsive case
only, with bounded from below, is
unquestionably admitted by the compatibility conditions. A class of diffusion
processes is exemplified, such that the attractive forcing is allowed as well,
due to an appropriate compensation coming from the "pressure" term. The
compressible Euler flows form their subclass, when regarded as stochastic
processes. We establish circumstances under which the dispersion of passive
contaminants in a forced, deterministic or random, flow can be consistently
interpreted as a Markovian diffusion process. In case of conservative forcing
the repulsive case only, with bounded
from below, is unquestionably admitted by the compatibility conditions. A class
of diffusion processes is exemplified, such that the attractive forcing is
allowed as well, due to an appropriate compensation coming from the "pressure"
term. The compressible Euler flows form their subclass, when regarded as
stochastic processes.Comment: 10 pages, Late
The physical meaning of the "boost-rotation symmetric" solutions within the general interpretation of Einstein's theory of gravitation
The answer to the question, what physical meaning should be attributed to the
so-called boost-rotation symmetric exact solutions to the field equations of
general relativity, is provided within the general interpretation scheme for
the ``theories of relativity'', based on group theoretical arguments, and set
forth by Erich Kretschmann already in the year 1917.Comment: 9 pages, 1 figure; text to appear in General Relativity and
Gravitatio
New mobilities across the lifecourse: A framework for analysing demographically-linked drivers of migration
Date of acceptance: 17/02/2015Taking the life course as the central concern, the authors set out a conceptual framework and define some key research questions for a programme of research that explores how the linked lives of mobile people are situated in timeâspace within the economic, social, and cultural structures of contemporary society. Drawing on methodologically innovative techniques, these perspectives can offer new insights into the changing nature and meanings of migration across the life course.Publisher PDFPeer reviewe
Are social phobia and paranoia related, and which comes first?
.001), also with a dose response, i.e. more PS symptoms yield more SPh symptoms. PS emerging after SPh was not significant. This study confirmed the association of SPh and PS in a general population. Possibly this is caused by shared underlying psychological and behavioural processes. There was some indication that paranoid ideation precedes the development of SPh, but this must be considered with caution. Clinical implications are discussed. Keywords: paranoid symptoms; social phobia; comorbidity; general population surve
Influence of Neutron Enrichment on Disintegration Modes of Compound Nuclei
Cross sections, kinetic energy and angular distributions of fragments with
charge 6Z28 emitted in 78,82Kr+40C at 5.5 MeV/A reactions were
measured at the GANIL facility using the INDRA apparatus. This experiment aims
to investigate the influence of the neutron enrichment on the decay mechanism
of excited nuclei. Data are discussed in comparison with predictions of
transition state and Hauser-Feshbach models.Comment: 8 pages, 1 figure, paper presented at the First Workshop on "State of
the Art in Nuclear Cluster Physics" 13-16 May, 2008, at Strasbourg, France
(SOTANCP2008) and accepted for publication at International Journal of Modern
Physics E (Special Issue), Proceedings of SOTANCP2008 (to be published
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