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[en] The results of an experimental approach to the identification and characterization of the astrophysical weed vinyl cyanide in the 210-270 GHz region are reported. This approach is based on spectrally complete, intensity-calibrated spectra taken at more than 400 different temperatures in the 210-270 GHz region and is used to produce catalogs in the usual astrophysical format: line frequency, line strength, and lower state energy. As in our earlier study of ethyl cyanide, we also include the results of a frequency point-by-point analysis, which is especially well suited for characterizing weak lines and blended lines in crowded spectra. This study shows substantial incompleteness in the quantum-mechanical (QM) models used to calculate astrophysical catalogs, primarily due to their omission of many low-lying vibrational states of vinyl cyanide, but also due to the exclusion of perturbed rotational transitions. Unlike ethyl cyanide, the QM catalogs for vinyl cyanide include analyses of perturbed excited vibrational states, whose modeling is more challenging. Accordingly, we include an empirical study of the frequency accuracy of these QM models. We observe modest frequency differences for some vibrationally excited lines.
[en] The different simple methods for evaluation of vibrational enhancement factor of nuclear level density with allowance for collective state damping are considered and compared. A practical method for calculation of nuclear level density is recommended taking into account quadrupole and octupole vibrational states. (author)
[en] The extent of particle-phonon mixing in 248Cf and 249Cf has been determined using the 249Cf(d,t) and 249Cf(d,d') reactions. K/sup pi/=2- bands were identified at 593 and 1477 keV in 248Cf. Since the only K/sup pi/=2- neutron two quasiparticle configuration expected below 2 MeV in 248Cf is ]9/2-734;5/2+ 622closing-brace2-, the second K/sup pi/=2- band is considered to be predominantly of phonon character. In 249Cf a K/sup pi/=5/2+ band at 145 keV, known from decay scheme studies, receives a measurable population in the (d,d') reaction. The phonon admixture in the 5/2+ state which results from the ]9/2-734direct-product2- phononclosing-brace configuration was determined to be (29plus-or-minus5) %. The collective admixture in the 5/2+ state was also calculated from an octupole particle-hole interaction and was found to be 35%, in good agreement with the experimental value. The anomalously low energy of the 5/2+ state could not be entirely reproduced by this calculation