70,764 research outputs found
Computation of the Binding Energies in the Inverse Problem Framework
We formalized the nuclear mass problem in the inverse problem framework. This
approach allows us to infer the underlying model parameters from experimental
observation, rather than to predict the observations from the model parameters.
The inverse problem was formulated for the numericaly generalized the
semi-empirical mass formula of Bethe and von Weizs\"{a}cker. It was solved in
step by step way based on the AME2012 nuclear database.
The solution of the overdetermined system of nonlinear equations has been
obtained with the help of the Aleksandrov's auto-regularization method of
Gauss-Newton type for ill-posed problems. In the obtained generalized model the
corrections to the binding energy depend on nine proton (2, 8, 14, 20, 28, 50,
82, 108, 124) and ten neutron (2, 8, 14, 20, 28, 50, 82, 124, 152, 202) magic
numbers as well on the asymptotic boundaries of their influence. These results
help us to evaluate the borders of the nuclear landscape and show their limit.
The efficiency of the applied approach was checked by comparing relevant
results with the results obtained independently.Comment: 9 pages, 1 figure, Proceedings of the International Symposium on
Exotic Nuclei EXON-2016, Kazan, Russia, 4-10 September 2016. based on
arXiv:1602.0677
Simultaneously non-linear energy calibration of CMS calorimeters for single pions and electrons
CMS calorimeter energy calibration was done in the full CMS simulated
geometry for the pseudorapidity region eta = 0. The samples of single pion
events were generated with a set of incident energies from 5 GeV to 3 TeV and
for single electrons from 5 to 500 GeV. The analysis of the simulated data
shows that standard calibration using just sampling coefficients for
calorimeter parts with different sampling ratio gives nonlinear calorimeter
response. Non-linear calibration technique was applied simultaneously for pion
and electron beams which is preparation for jets energy reconstruction. It
improve calorimeter energy resolution for pions and restore the calorimeter
linearity.Comment: 7 pages, 2 figures, latex fil
Screening for congenital hypothyroidism in Maltese newborns using cord blood
Routine screening for congenital hypothyroidism (CHT) has been introduced because clinical features of CHT may not be evident before the baby is a few weeks old and treatment at this stage may already be too late. Since a newborn testing programme employing liquid cord blood for other conditions had already been developed in the University of Malta and the Department of Health, we explored the possibility of implementing newborn thyroid testing using liquid cord blood. A similar programme had been implemented successfully in Finland and Philadelphia. Between September 1989 and August 1995 around 32,000 newborns were tested. This is nearly complete ascertainment. Preliminary testing was by radioimmunoassay for TSH. The sera of those with TSH levels more than 13mU/l were further tested for free T4. If the free T4 level was below 12 pmol/l, the babies were recalled for clinical evaluation and repeat testing. Other babies were recalled for technical reasons, giving a total recall rate of 3.88%. CHT was identified in seven newborns and treatment started within 3 weeks of delivery. One baby was reported normal on screening but was suspected to have CHT on clinical grounds at 3 weeks of age, confirmed biochemically. The incidence of CHT in Malta is therefore 1 in 4500.peer-reviewe
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