From finite nuclei to the nuclear liquid drop: leptodermous expansion based on the self-consistent mean-field theory

The parameters of the nuclear liquid drop model, such as the volume, surface, symmetry, and curvature constants, as well as bulk radii, are extracted from the non-relativistic and relativistic energy density functionals used in microscopic calculations for finite nuclei. The microscopic liquid drop energy, obtained self-consistently for a large sample of finite, spherical nuclei, has been expanded in terms of powers of A^{-1/3} (or inverse nuclear radius) and the isospin excess (or neutron-to-proton asymmetry). In order to perform a reliable extrapolation in the inverse radius, the calculations have been carried out for nuclei with huge numbers of nucleons, of the order of 10^6. The Coulomb interaction has been ignored to be able to approach nuclei of arbitrary sizes and to avoid radial instabilities characteristic of systems with very large atomic numbers. The main contribution to the fluctuating part of the binding energy has been removed using the Green's function method to calculate the shell correction. The limitations of applying the leptodermous expansion to actual nuclei are discussed. While the leading terms in the macroscopic energy expansion can be extracted very precisely, the higher-order, isospin-dependent terms are prone to large uncertainties due to finite-size effects.Comment: 13 pages revtex4, 7 eps figures, submitted to Phys. Rev.

Arithmetic Spacetime Geometry from String Theory

An arithmetic framework to string compactification is described. The approach is exemplified by formulating a strategy that allows to construct geometric compactifications from exactly solvable theories at $c=3$. It is shown that the conformal field theoretic characters can be derived from the geometry of spacetime, and that the geometry is uniquely determined by the two-dimensional field theory on the world sheet. The modular forms that appear in these constructions admit complex multiplication, and allow an interpretation as generalized McKay-Thompson series associated to the Mathieu and Conway groups. This leads to a string motivated notion of arithmetic moonshine.Comment: 36 page

Amplitude analysis of four-body decays using a massively-parallel fitting framework

The GooFit Framework is designed to perform maximum-likelihood fits for arbitrary functions on various parallel back ends, for example a GPU. We present an extension to GooFit which adds the functionality to perform time-dependent amplitude analyses of pseudoscalar mesons decaying into four pseudoscalar final states. Benchmarks of this functionality show a significant performance increase when utilizing a GPU compared to a CPU. Furthermore, this extension is employed to study the sensitivity on the $D^0 - \bar{D}^0$ mixing parameters $x$ and $y$ in a time-dependent amplitude analysis of the decay $D^0 \rightarrow K^+\pi^-\pi^+\pi^-$. Studying a sample of 50 000 events and setting the central values to the world average of $x = (0.49 \pm0.15) \%$ and $y = (0.61 \pm0.08) \%$, the statistical sensitivities of $x$ and $y$ are determined to be $\sigma(x) = 0.019 \%$ and $\sigma(y) = 0.019 \%$.Comment: Proceedings of the 22nd International Conference on Computing in High Energy and Nuclear Physics, CHEP 201

Einstellung zum Alkoholkonsum und Motivation zur Veränderung des Trinkverhaltens bei Schwangeren- Eine Validierung des Transtheoretischen Modells der Verhaltensänderung

Ziel dieser Studie war es, die Motivation von schwangeren Frauen zum Alkoholverzicht zu untersuchen. Ebenso sollte die Anwendbarkeit des Transtheoretischen Modells der Verhaltensänderung auf das Problemverhalten des Alkoholkonsums in der Schwangerschaft überprüft werden. Weitere Fragestellungen befassten sich mit dem Vergleich des Alkoholkonsums von Frauen, die sich in Familienstand, Ausbildungsstand und Rauchverhalten unterschieden. Es handelt sich um eine Querschnittstudie, in der Frauen aus 5 gynäkologischen Arztpraxen während eines Besuches bei ihrem Gynäkologen ein Fragebogen vorgelegt wurde. Insgesamt 256 Schwangere zwischen der 3. und 40. Schwangerschaftswoche nahmen an der Befragung teil. Ihr Alter betrug im Durchschnitt 29,9 Jahre (SD 5,6). Erstgebärende waren 145 Frauen, weitere 79 Frauen waren in ihrer zweiten Schwangerschaft und nur wenige Teilnehmerinnen waren in ihrer dritten, vierten oder fünften Schwangerschaft. 1. Die Dimensionalität der Konstrukte des TTM, wie sie in vorhergehenden Untersuchungen gefunden wurde, kann im Wesentlichen bestätigt werden. 2. Die Gütekriterien der zur Operationalisierung der Konstrukte verwendeten Skalen sind befriedigend. 3. Einen Alkoholkonsum während der Schwangerschaft geben 44 % aller Teilnehmerinnen an. Der durchschnittliche Alkoholkonsum beträgt 0,5 (SD = 0,95) alkoholischen Getränke bei einem Anlass während der letzten 30 Tage, wobei ein Maximalwert von 5 Getränken bei einem Anlass berichtet wird. Auf die Frage nach der Anzahl der Tage, an denen während der letzten 10 Tage ein alkoholisches Getränk getrunken wurde, geben die Teilnehmerinnen einen Mittelwert von 1,3 (SD = 0,63) Tagen an, das Maximum beträgt 5 Tage. Zur Frage nach der Anzahl der Anlässe, an denen seit Beginn der Schwangerschaft ein alkoholisches Getränk getrunken wurde, zeigt sich ein Mittelwert von 2,1 (SD = 1,7) Anlässen mit einem Maximalwert von mehr als 20 Anlässen. Sechs Frauen geben einen maximalen Alkoholkonsum von 4 oder mehr Getränken bei einem Anlass an. 4. Es zeigt sich ein signifikant höherer Alkoholkonsum bei unverheirateten Schwangeren im Vergleich zu Verheirateten. 5. Einen signifikant höheren Alkoholkonsum geben Frauen mit Universitätsabschluss und Frauen in Führungspositionen an. 6. Raucherinnen trinken während der Schwangerschaft nicht mehr Alkohol als Nichtraucherinnen

Eutactic quantum codes

We consider sets of quantum observables corresponding to eutactic stars. Eutactic stars are systems of vectors which are the lower dimensional ``shadow'' image, the orthogonal view, of higher dimensional orthonormal bases. Although these vector systems are not comeasurable, they represent redundant coordinate bases with remarkable properties. One application is quantum secret sharing.Comment: 6 page

Serre's "formule de masse" in prime degree

For a local field F with finite residue field of characteristic p, we describe completely the structure of the filtered F_p[G]-module K^*/K^*p in characteristic 0 and $K^+/\wp(K^+) in characteristic p, where K=F(\root{p-1}\of F^*) and G=\Gal(K|F). As an application, we give an elementary proof of Serre's mass formula in degree p. We also determine the compositum C of all degree p separable extensions with solvable galoisian closure over an arbitrary base field, and show that C is K(\root p\of K^*) or K(\wp^{-1}(K)) respectively, in the case of the local field F. Our method allows us to compute the contribution of each character G\to\F_p^* to the degree p mass formula, and, for any given group \Gamma, the contribution of those degree p separable extensions of F whose galoisian closure has group \Gamma.Comment: 36 pages; most of the new material has been moved to the new Section

Non-Markovian large amplitude motion and nuclear fission

The general problem of dissipation in macroscopic large-amplitude collective motion and its relation to energy diffusion of intrinsic degrees of freedom of a nucleus is studied. By applying the cranking approach to the nuclear many body system, a set of coupled dynamical equations for the collective classical variables and the quantum mechanical occupancies of the intrinsic nuclear states is derived. Different dynamical regimes of the intrinsic nuclear motion and its consequences on time properties of collective dissipation are discussed. The approach is applied to the descant of the nucleus from the fission barrier.Comment: 9 pages and 3 figure

Continuum corrections to the level density and its dependence on excitation energy, n-p asymmetry, and deformation

In the independent-particle model, the nuclear level density is determined from the neutron and proton single-particle level densities. The single-particle level density for the positive-energy continuum levels is important at high excitation energies for stable nuclei and at all excitation energies for nuclei near the drip lines. This single-particle level density is subdivided into compound-nucleus and gas components. Two methods were considered for this subdivision. First in the subtraction method, the single-particle level density is determined from the scattering phase shifts. In the Gamov method, only the narrow Gamov states or resonances are included. The level densities calculated with these two methods are similar, both can be approximated by the backshifted Fermi-gas expression with level-density parameters that are dependent on A, but with very little dependence on the neutron or proton richness of the nucleus. However, a small decrease in the level-density parameter was predicted for some nuclei very close to the drip lines. The largest difference between the calculations using the two methods was the deformation dependence on the level density. The Gamov method predicts a very strong peaking of the level density at sphericity for high excitation energies. This leads to a suppression of deformed configurations and, consequently, the fission rate predicted by the statistical model is reduced in the Gamov method.Comment: 18 pages 24 figure

Diagnostic criterion for crystallized beams

Small ion crystals in a Paul trap are stable even in the absence of laser cooling. Based on this theoretically and experimentally well-established fact we propose the following diagnostic criterion for establishing the presence of a crystallized beam: Absence of heating following the shut-down of all cooling devices. The validity of the criterion is checked with the help of detailed numerical simulations.Comment: REVTeX, 11 pages, 4 figures; submitted to PR

Effective moment of inertia for several fission reaction systems induced by nucleons, light particles and heavy ions

Compound nucleus effective moment of inertia has been calculated for several fission reaction systems induced by nucleons, light particles, and heavy ions. Determination of this quantity for these systems is based upon the comparison between the experimental data of the fission fragment angular distributions as well as the prediction of the standard saddle-point statistical model (SSPSM). For the systems, the two cases, namely with and without neutron emission corrections were considered. In these calculations, it is assumed that all the neutrons are emitted before reaching the saddle point.It should be noted that the above method for determining of the effective moment of inertia had not been reported until now and this method is used for the first time to determine compound nucleus effective moment of inertia. Hence, our calculations are of particular importance in obtaining this quantity, and have a significant rule in the field of fission physics. Afterwards, our theoretical results have been compared with the data obtained from the rotational liquid drop model as well as the Sierk model, and satisfactory agreements were found. Finally, we have considered the effective moment of inertia of compound nuclei for the systems that formed similar compound nuclei at similar excitation energies.Comment: 9 pages, 2 Figures, 2 Table