2,460 research outputs found
Stately Ceremony and Carnival.: Voting and Social Pressure in Germany and Britain between the World Wars
Die dichte Beschreibung konkreter Wahlpraktiken in Deutschland und Großbritannien zwischen den Weltkriegen zeigt viele Kontinuitäten aus dem 9. Jahrhundert. Während die britische Selbstinszenierung des Gemeinwesens am Wahltag viel von ihrem Volksfestcharakter behielt, waren deutsche Wahlen von mehr Ernsthaftigkeit und Sorge um soziale Hierarchien, von stärkerer Empfindsamkeit gegenüber Regelverletzungen und einem größeren Regulierungsbedarf der Konfliktformen geprägt. Die Mentalitätsunterschiede gehen darauf zurück, dass anders als in Großbritannien vor 1914 freie Wahlen in Deutschland mühsam der Obrigkeit abgetrotzt werden mussten. Einen Epilog fand diese Geschichte im Wahlgeheimnis, das auch nach 1918 nicht überall vollständig gesichert war. Damit lastete bis in die 1930er auf deutschen sehr viel höherer sozialer Druck als auf britischen Wählern
Variational Rovibrational Calculation For Linear Tetraatomic Molecules: I. The C8v4 Approach
Variational rovibrational calculations for small molecules with up to 3 atoms are nowadays a routine task.\footnote{\ Tennyson, \textit{J. Chem. Phys.} \textbf{145}, 120901 (2016).} By employing accurate potential energy surfaces it is possible to achieve so called “spectroscopic accuracy” of 1 cm for small linear molecules.\footnote{\ Schröder and Sebald, \textit{J. Chem. Phys.} \textbf{144}, 044307 (2016); Makhnev~\textit{et al.}, \textit{J. Phys. Chem. A} \textbf{122}, 1326 (2018).} However, rovibrational calculations for linear molecules with more than 3 atoms are still rather scarce.\footnote{\ Mladenovi\'{c}, \textit{J. Chem. Phys.} \textbf{141}, 224304 (2014); Chubb~\textit{et al.}, \textit{J. Chem. Phys.} \textbf{149}, 14101 (2018).} A new variational method (C8v4) will be presented that is able to obtain rovibrational term energies and wave functions of tetraatomic linear molecules based on Watsons isomorphic Hamiltonian for linear molecules.\footnote{\ Watson, \textit{Mol. Phys.} \textbf{14}, 465 (1970).} The rovibrational wavefunction is expanded in (symmetrized) products of harmonic oscillator (1D and 2D) and rigid-rotor functions. The intricacies related to the vibrational angular momentum in linear molecules require a careful study of symmetry properties. Kinetic energy matrix elements in the chosen basis set can be evaluated in a fast mixed numerical/analytical fashion. The main computational bottlenecks are the integration of the potential energy matrix and the diagonalisation of the rovibrational Hamiltonian. An efficient hybrid MPI/OMP parallelization has been implemented, exploiting the block structure of the Hamiltonian, that yields a significant reduction of the computational time. The diagonalization employs a -contraction scheme that reduces the number of basis functions in the final rovibrational Hamilonian by at least an order of magnitude. Example benchmark calculations for acetylene (HCCH) are presented. The converged () results for HCCH up to accurately reproduce earlier variational calculations\footnote{\ Bramley and Handy, \textit{J. Chem. Phys.} \textbf{98}, 1378 (1993).} in both and symmetry
Theoretical high-resolution spectroscopy for reactive molecules in astrochemistry and combustion processes
Variational Rovibrational Calculation For Linear Tetraatomic Molecules: Ii. The B11244 Story Retold
The linear propynylidynium -CH () is part of the select group of interstellar cations. Its discovery was accompanied by a controversy in the astrophysical community.\footnote{\ Pety~\textit{et al.}, \textit{Astron. Astrophys.} \textbf{548}, 68 (2012); \ Huang~\textit{et al.}, \textit{Astrophys. J. Lett.} \textbf{768}, 25 (2013).} Following its initial detection, theoretical calculations questioned the assignment based on 2\textsuperscript{nd} order vibrational perturbation theory (VPT2) calculations. The matter was ultimately resolved by laboratory rotational spectra.\footnote{\ Br\"{u}nken~\textit{et al.}, \textit{Astrophys. J. Lett.} \textbf{783}, 36 (2014).} The failure of VPT2 was subsequently attributed to a shallow CCC bending potential.\footnote{\ Botschwina \textit{et al.}, \textit{Astrophys. J.} \textbf{787}, 72 (2014).} Discrete Variable Representation (DVR) calculations\footnote{\ Mladenovi\'{c} \textit{J. Chem. Phys.} \textbf{141}, 224304 (2014).} later confirmed the ratio but resulted in a large sextic centrifugal distortion constant exceeding the astronomical value by an order of magnitude.
Using a new variational method for tetraatomic linear molecules (C8v4; see also P5277), based on Watsons isomorphic Hamiltonian for linear molecules, theory and experiment are reconciled. The C8v4 calculations confirm the small size of obtained in previous experimental studies. A high-level composite \textit{ab initio} potential energy function (PEF) has been developed, combining explicitly correlated coupled-cluster results with corrections for core-valence correlation, scalar relativistic effects and higher-order correlation as well as the diagonal Born-Oppenheimer correction. Large scale C8v4 calculations using this PEF show excellent agreement with the available experimental rotational\textsuperscript{\emph{a,c}} and vibrational parameters.\footnote{\ Br\"{u}nken~\textit{et al.}, \textit{J. Phys. Chem. A} \textbf{123}, 8053 (2019).} The presented rotational spectroscopic parameters of excited vibrational states should facilitate forthcoming experimental spectroscopic studies on -CH
An all-optical buffer based on temporal cavity solitons operating at 10 Gb/s
We demonstrate the operation of an all-optical buffer based on temporal
cavity solitons stored in a nonlinear passive fiber ring resonator. Unwanted
acoustic interactions between neighboring solitons are suppressed by modulating
the phase of the external laser driving the cavity. A new locking scheme is
presented that allows the buffer to operate with an arbitrarily large number of
cavity solitons in the loop. Experimentally, we are able to demonstrate the
storage of 4536 bits of data, written all-optically into the fiber ring at 10
Gb/s, for 1 minute.Comment: 5 pages, 4 figure
The evolution of tangibles, financial and social security wealth over the lifecycle: estimates for Germany
"Using survey and administrative micro data, the authors describe the wealth distribution in Germany between 1978 and 2003, focusing on the birth cohort 1939 to 1953 resident in West Germany. Estimates are provided for three types of wealth, financial wealth, real wealth and social security wealth, i.e. the number of accumulated earning points in Germany's public pension insurance. While financial and real wealth are rather unequally distributed, inequality in accumulated earning points is substantially lower, indicating that Germany's pay-as-you-go pension system plays a prominent role in mitigating the inequality in overall wealth after retirement." (author's abstract
Studying the mass sensitivity of air-shower observables using simulated cosmic rays
Using CORSIKA simulations, we investigate the mass sensitivity of cosmic-ray
air-shower observables for sites at the South Pole and Malarg\"ue, Argentina,
the respective locations of the IceCube Neutrino Observatory and the Pierre
Auger Observatory. Exact knowledge of observables from air-shower simulations
was used to study the event-by-event mass separation between proton, helium,
oxygen, and iron primary cosmic rays with a Fisher linear discriminant
analysis. Dependencies on the observation site as well as the energy and zenith
angle of the primary particle were studied in the ranges from
eV and to : they are mostly weak and
do not change the qualitative results. Promising proton-iron mass separation is
achieved using combined knowledge of all studied observables, also when typical
reconstruction uncertainties are accounted for. However, even with exact
measurements, event-by-event separation of intermediate-mass nuclei is
challenging and better methods than the Fisher discriminant and/or the
inclusion of additional observables will be needed. As an individual
observable, high-energy muons (GeV) provide the best event-by-event
mass discrimination, but the combination of muons of any energy and
provides already a high event-by-event separation between
proton-iron primaries at both sites. We also confirm that the asymmetry and
width parameters of the air-shower longitudinal profile, and , are mass
sensitive. Only seems to be suitable for event-by-event mass separation,
but can potentially be used to statistically determine the proton-helium
ratio. Overall, our results motivate the coincident measurement of several
air-shower observables, including at least and the sizes of
the muonic and electromagnetic shower components, for the next generation of
air-shower experiments
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