Resonances in electron-impact electron detachment of C-2(-)

Molecular R-matrix with pseudostate calculations are reported for the electron-impact ionization cross section of the carbon dimer anion. A (1)Sigma(+)(g) g resonance is found near the detachment threshold and two further resonances, of (3)Pi(g) and (1)Pi(g) symmetry, are found near 10 eV close to the structures observed experimentally. These unusual shape resonances are a result of the competition between the repulsive Coulomb interaction and the large, attractive polarizability of C-2(-). Use of the Born approximation to allow for higher partial waves gives a total cross section close to that observed experimentally

R-matrix calculations of electron-molecule collisions with C2 and C-2.

The C2 molecule is very important astrophysically as well as terrestrially. Its spectrum is known from the comets, the interstellar mediums and the atmospheres of cool carbon stars. C2 is present in flames and electric discharges through carbon-containing materials, and could be important at the edge of fusion plasmas. Nevertheless, there seem to be no preceding published studies of electron collisions with neutral C2. On the other hand, there are a number of studies available for C2 ion. The challenge of studying electron collisions with C2 is the unusually large number of low-lying electronic states, which are themselves difficult to represent using standard ab initio methods. Furthermore, the system supports several bound states even though the exact number is not firmly established. This thesis describe the electron collision processes with the dicarbon molecule and its anion at the energies up to 10 eV. Specific attention is given to determine the formation of the bound states of C2 and a low-lying resonance of C as a function of internuclear separation. While the calculations on the system used the standard implementation of the UK i-matrix method, those on C required both the molecular .ft-matrix method with pseudo-states and the partitioned /2-matrix method to be employed. The effectiveness of these procedures for this problem is discussed

Re-matrix calculations of electron-molkecule collisions with C2 and C2

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Forest influence on flash floods in small streams

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Precipitation Regime and Temporal Changes in the Central Danubian Lowland Region

The aim of this paper is to investigate the statistical aspects of multiannual variability of precipitation at the Hurbanovo station, Slovakia, over 140 years (1872–2011). We compare the long-term variability of annual precipitation for Hurbanovo (Slovakia), Brno (Czech Republic), Vienna (Austria), and Mosonmagyarovar (Hungary) stations using autocorrelation and spectral analysis methods. From the long-term point of view, there is no consistent trend in the annual precipitation; only a multiannual variability has been detected. Consequently we identify changes in the distribution of annual maximum daily precipitation for Hurbanovo during different periods for winter-spring and summer-autumn seasons using histograms, empirical exceedance curves, and frequency curves of daily precipitation. Next, we calculate the periods of days without precipitation exceeding 29 days between 1872 and 2011. The longest period of days without precipitation was 83 days in 1947. The statistical analysis does not confirm our initial hypothesis that neither high daily precipitation (over 51.2 mm per day) nor long dry periods (more than 50 days without precipitation) would occur more frequently nowadays. We assume that the decrease in annual precipitation over the period 1942–2011 (compared to 1872–1941) is caused by the less frequent occurrence of daily precipitation between 0.4 and 25.6 mm