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961.
I. Espe B. Skaali P. O. Tjøm S. M. Lee M. Rozkoš B. Elbek 《Czechoslovak Journal of Physics》1979,29(11):1208-1214
Highly excited compound nuclei of74Kr have been formed by bombardment of58Ni with 70 MeV16O ions. The spectra of protons and -particles resulting from the decay of the compound nucleus (and several daughter nuclei) have been recorded at laboratory angles from 30° to 155°. The CM differential cross sections corresponding to definite energies for the particles emitted were calculated from the data. The charged particle spectra and the angular distributions show that evaporation processes are dominant. A study of spectral shapes and angular distributions has to some extent made it possible to distinguish primary particles from those evaporated after the emission of one or several particles.On leave fromFaculty of Mathematics and Physics, Charles University, Prague, Czechoslovakia. 相似文献
962.
H. Essel K. Hartel W. Henning P. Kienle H. J. Körner K. E. Rehm P. Sperr W. Wagner H. Spieler 《Zeitschrift für Physik A Hadrons and Nuclei》1979,289(3):265-271
Mass and charge transfer was investigated for the system136Xe+208Pb at 5.9 MeV/nucleon incident energy with aΔE —E-time of flight telescope. The angle and energy integrated cross section for the strongly damped events was found to be 510 mb, very close to the total reaction cross section. The width of the mass distribution as function of the total kinetic energy loss was measured and is compared to the width of the corresponding charge distribution. An upper limit of 1 μb has been found for processes with very large mass transfer. 相似文献
963.
Brillouin scattering is observed in the InxGa1?xP solid solution with 0.38 ? × ? 0. The composition dependences of the longitudinal and transverse acoustic phonons propagating along the [111] direction are investigated and compared with the expressions derived by Lakshmi et al. from the random element isodisplacement theory. Pronounced broadening of the Brillouin peaks is observed with the increasing amount of In in GaP. 相似文献
964.
A. Beckmann K. D. Böklen G. Bremer D. Elke 《Zeitschrift für Physik A Hadrons and Nuclei》1975,272(2):143-145
Using the atomic beam magnetic resonance method the Zeeman interactions of12C in the3 P 1 and3 P 2 states at magnetic fields of about 3.4 kOe have been measured. The measured quantities areg J (3 P 1)?gJ(3 P 2)=15.4(1.0)·10?6 g J (3 P 2)=1.5010616 (50), from which the following value for gJ(3P1) can be calculated:g J (3 P 1)=1.5010770 (50). The experimental results are in moderate agreement with theoretical calculations. 相似文献
965.
K. D. Böklen T. Bossert W. Foerster H. H. Fuchs G. Nachtsheim 《Zeitschrift für Physik A Hadrons and Nuclei》1975,274(3):195-201
Using the atomic beam magnetic resonance method, the five hyperfine structure separations in the 4f 3 6s 2 4I9/2 ground state of 59 141 Pr have been measured. The results are:F F′ E FF′ * /h (MHz) 7 6 6477.913423(17) 6 5 5556.359848 (6) 5 4 4633.023306 (2) 4 3 3708.201146 (5) 3 2 2782.190601(15) From these quantities, the multipole interaction constantsA k,k=1, 2, 3, 4 between the nucleus and the electron shell have been calculated.A 4 especially then served to give the following limit for the intrinsic hexadecapole moment: ¦Q 40¦<0.4eb 2. Furthermore, theg J -factors of the4 I multiplet have been measured at magnetic fields of 300 Oe. The results are:g J(4 I 9/2)=0.7310371(15)g J(4 I 11/2)=0.9651476(20)g J(4 I 13/2)=1.1063197(40)g J(4 I 15/2)=1.197963 (30) Small corrections due to perturbations by neighbouring fine structure levels are included. 相似文献
966.
Using a perturbation theoretical argument an effective variational ansatz for the ground state is given. The formula works for arbitrary coupling strengths. The anharmonic oscillator is presented as an example and a comparison with other methods is made. 相似文献
967.
P. E. Sulewski E. Bucher N. Stücheli C. S. Oglesby K. Friemelt M. Vögt J. R. Baumann Ch. Kloc 《Applied Physics A: Materials Science & Processing》1992,54(1):79-83
Recently, an anomalously large redshift of the absorption edge with electric field was claimed for -GaSe1–x
S
x
layered crystals. We have studied Bridgman grown -GaSe crystals as well as vapor transport grown -GaS, and 2H-WSe2. While we have observed a shift in the absorption edge for -GaSe similar to that reported in previous work, our results demonstrate that the redshift arises from Joule heating, and is thus temperature induced, rather than intrinsic. For -GaS, much larger resistivities virtually eliminate Joule heating, and our measurements of the electric field induced absorption edge shift yield an estimated upper limit of approximately 0.04 meV · cm/kV for a field of 2.4×103 kV/cm, in good agreement with the theoretical value expected for the Franz-Keldysh effect.Also at University of Konstanz 相似文献
968.
J. Döring L. Funke W. Wagner G. Winter 《Zeitschrift für Physik A Hadrons and Nuclei》1991,339(3):425-426
Excited states in the doubly-odd nucleus82Rb have been investigated via the reactions79Br(,n) and78Se(7Li,3n) using in-beam-ray spectroscopy. The level energy of the longlived 5– isomer has been determined to 68.3 keV which is below the energy of the 2– state found at 88.9 keV with a lifetime of=2.4(2) ns. A sequence of positive-parity states beginning with a 6+ level at 191.3 keV (=20(3) ns) and extending to a (10+) level has been interpreted to contain the two-particle configuration (g
9/2
9/2) and collective excitations. 相似文献
969.
970.
F. Heine T. Faestermann A. Gillitzer J. Homolka M. Köpf W. Wagner 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(2):225-226
In fusion reactions of58Ni beams with54Pe and58Ni target nuclei neutron deficient evaporation residues have been produced and separated from the beam in an electrostatic deflector with large acceptance. The recoil nuclei were implanted and detected in an array of 100 PIN photodiodes, where also their particle decays were recorded. The assignment of the 0.81 MeV proton line to the decay of109I could be experimentally proven by the observation, that it is followed by the 3.31 MeV alpha emission from108Te. A proton decay from112Cs was not observed. The decay energies of a number of known emitters have been measured with better precision.Dedicated to Prof. Dr. P. Kienle on the occasion of his 60th birthday 相似文献