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1

Chaos in the model atomic nuclei and other applications of quantum mechanics

Sveda Ρ., Kratochvil C.

Modelling and Optimization of Physical Systems

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2011

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z. 10

85--88

EN

Quantum chaos was discovered in atomic nuclei, which influences the course of nuclear reactions. But it turned out that the quantum chaos occurs universally for a broad class of problems, for example, when analyzing the distribution of spectral lines in the optical, acoustic, microwave technology. And also quantum chaos is discussed in connection with the construction of quantum computers.

CS

Kvantovy chaos byl objeven u atomovych jader, kde ovlivnuje prubeh jadernych reakci. Ovsem ukazalo se, ze kvantovy chaos se vyskytuje univerzalne u sirokych tfid problemu, napfiklad pfi analyze rozdeleni spektralnych car v optice, v akustice, v mikrovlnne technice. A o kvantovem chaosu se mluvi i v souvislosti s uvahami o konstrukci kvantovych pocitacu.

2

A theoretical model of the human eye based on ultrasound and corneal data

Falhar M., Rehak J.

Optica Applicata

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2009

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Vol. 39, nr 1

195--210

EN

The purpose of this study was to create a theoretical model of the eye based on a comparison of the real spherical equivalent of the eye and the calculated value of the axial refraction. The main contribution of this model is that it enables calculation of the equatorial plane of the lens for accurate assessment of the IOL position for a spherical eye model. The Gullstrand model of the eye was used as the source eye model and this was modified for the purposes of this study. The axial refraction of the final model of the eye was compared with the spherical equivalent. The accuracy of the developed model was statistically confirmed using statistic tests. Individual calculation of the axial refraction using it shows that IOL calculation is possible without any general statistical presumptions. It permits the calculation of variables with an accuracy accepted by inferential statistics. The accuracy of this theoretical eye model however, is limited by extreme values of variables - an extreme value provides a less accurate result.

3

Pre- and post-scission neutron multiplicities in the frame of the Bass model

Rudolf G.

Nukleonika

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1998

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Vol. 43, nr 3

265-274

EN

Pre-scission neutron multiplicities have been shown to allow the measure of the livetime of a fissioning nucleus. This is achieved by comparing the experimental multiplicity to that predicted by statistical models after having introduced a delay time for the re-separation. Fission has been found to be a slow process. Therefore, pre-scission neutron multiplicities should also allow to measure the extra-extra-push, i.e. the energy above the Bass barrier needed, according to dynamical models, to achieve fusion and not fast-fission. In the case, the precise value of the livetime is not the goal of the experiment. Therefore, simpler models than the statistical model can be used. This paper presents a very simple method, based on the Bass model, to predict phenomenologically pre- and post-scission neutron multiplicities.

PL

W pracy pokazano, że krotności neutronów typu pre-scission pozwalają na wyznaczenie czasu życia rozszczepiającego się jądra. Osiągnąć to można drogą porównania krotności doświadczalnych z krotnościami przewidywanymi przez model statystyczny po wprowadzeniu czasu separacji. Stwierdzono, że rozszczepienie jest procesem powolnym. Tak więc krotności neutronów typu pre-scission powinny również pozwolić na pomiar energii powyżej bariery Bassa niezbędnej, zgodnie z modelami dynamicznymi, do osiągnięcia fuzji bez szybkiego rozszczepienia. W tym przypadku dokładna wartość czasu życia nie jest celem doświadczenia. Stąd można wykorzystać modele prostsze niż model statystyczny. W pracy zaprezentowano bardzo prosty model, oparty na modelu Bassa, aby przewidzieć fenomenologicznie krotności neutronów.

4

Neutron emission from (sup 101)Rh produced via (sup 12)C + (sup 89)Y reaction. Progress report

Szefliński Z., Popkiewicz M., Zagańczyk R.

Nukleonika

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1998

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Vol. 43, nr 3

309-320

EN

An array of eight large BC-501A liquid scintillators for use in neutron Time-Of-Flight (TOF) experiments was build. The array of neutron detectors MONA has been tested in the measurement of neutron spectra from spontaneous fission of (sup 252)Cf. The detector was also used to measure neutron spectra originated in the experiment at Warsaw Cyclotron. The neutron spectra from the heavy ion collision of (sup 12)C + (sup 89)Y system were measured at six selected angles by TOF method at average laboratory energy of 49.5 MeV. In order to extract primary neutron spectrum the unfolding procedure was applied. The temperature of the source was determined through off-line analysis and was found to be 1.62 MeV. The level density parameter a, was determined within the framework of a Fermi-gas model, to be equal to a = A/9.4.

PL

Zbudowano układ ośmiu dużych scyntylatorów ciekłych BC-501A do eksperymentu neutronowego z pomiarem czasu przelotu (TOF). Układ detektorów neutronowych MONA przetestowano mierząc widma neutronów pochodzących ze spontanicznego rozszczepienia (sup 252)Cf. Detektor wykorzystano również do pomiarów widm neutronów w eksperymencie przy Cyklotronie Warszawskim. Zmierzono widma neutronów w zderzeniach ciężkich jonów (sup 12)C + (sup 88)Y pod sześcioma wybranymi kątami metodą TOF przy średniej energii w układzie laboratoryjnym 49,5 MeV. Temperatura źródła wyznaczona w analizie "off line" równa jest 1,62 MeV. Parametr gęstości wyznaczono w ramach modelu gazu Fermiego: a = A/9.4

5

Letter of intent: investigation of the fission before K-equilibration

Jokić S., Vorkapić D., Ivanisević B., Kelić A., Todorović Z., Savović S., Botchev B., Zamani M., Fernandez F.

Nukleonika

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1998

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Vol. 43, nr 3

275-279

EN

We propose to study mass resolved fission fragment anysotropies and mass resolved neutron multiplicities for the (sup 12)C + (sup 232)Th and (sup 16)O + (sup 232)Th reactions at 74 MeV and 85 MeV laboratory energy, respectively. For (sup 12)C + (sup 232)Th and (sup 16)O + (sup 232)Th reaction we expect at lower energies the larger difference between angular anisotropy at symmetric and angular anisotropy at asymmetric division. The measurement of neutrons in coincidence with mass resolved fission fragments will enable to calculate mass resolved angular anisotropy with neutron correction taken into account. We could also expect possible angular anisotropy of pre-scission neutrons. We expect less neutrons in the fission fragment direction.

PL

W pracy zaproponowano badanie anizotropii fragmentów rozszczepienia i krotności neutronów w zależności od masy w reakcji (sup 12)C + (sup 232)Th i (sup 16)O + (sup 232)Th przy energii w układzie laboratoryjnym odpowiednio 74 i 85 MeV. Oczekujemy w przypadku tych reakcji przy niskich energiach, że różnica między anizotropią kątową w przypadku symetrycznym i niesymetrycznym będzie większa (...). Możemy również oczekiwać anizotropii kątowej neutronów przedrównowagowych oraz mniejszej liczby neutronów w kierunku rozlotu fragmentów rozszczepienia.

6

Dynamical Landau-Vlasov model as a source generator for Hanbury-Brown-Twiss correlations

Basrak Z.

Nukleonika

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1998

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Vol. 43, nr 3

337-344

EN

The Landau-Vlasov semi-classical dynamical model with its recent extension has been applied as a source generator for the evaluation of neutron-neutron correlations of the Hanbury-Brown-Twiss type. The correlation function calculated for the Ar + Au collision at 60 MeV/nucleon displays sensitivity to the reaction dynamics.

PL

W pracy zastosowano półklasyczny model dynamiczny Landaua-Vlasova z najnowszymi rozszerzeniami jako generator źródła do analizy korelacji neutron-neutron typu Hanbury-Brown, Twiss. Funkcja korelacyjna wyznaczona dla zderzenia Ar+Au przy energii 60 MeV/nukleon wykazuje zależność od dynamiki reakcji.

7

Influence of a quadrupole nucleus of the signal of an adjacent to it 1/2 spin nucleus in high resolution NMR spectra of liquid samples

Gryff-Keller A.

Bulletin of the Polish Academy of Sciences. Chemistry

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1998

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Vol. 46, No. 1

105-115

EN

In high resolution NMR spectra of liquid samples a signal of a nucleus A (I =1/2) scalar coupled with a higher spin nucleus X reflects the relaxation properties of the latter nucleus. This signal may have the form of a singlet or a more or less resolved multiplet with characteristic relative broadenings of individual lines. Recently some spectroscopic effects, earlier predicted by theory, which manifest themselves in unsymmetrical lineshapes of the signal of A, have been reported. Measurements of the scalar relaxation of the second kind or the lineshape analysis of the A signal may provide valuable information on molecular structure and dynamics. In this paper the above phenomena have been reviewed and illustrated with experimental examples.