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21.
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M. Gorska H. Grawe D. Foltescu D. B. Fossan R. Grzywacz J. Heese K. H. Maier M. Rejmund H. Roth R. Schubart Ö. Skeppstedt K. Spohr 《Zeitschrift für Physik A Hadrons and Nuclei》1995,353(3):233-234
The neutron deficient nucleus94Pd was identified and studied for the first time by in-beam spectroscopy. An I=(14+) isomer with t1/2=0.8 (2) s was observed in a recoil catcher setup inside the multi-detector -array OSIRIS. Filter detectors for neutrons and charged particles were used to identify the (2p2n) exit channel of the reaction58Ni+40Ca, populated with only 0.06% of the total evaporation residue cross section. The structure of the isomer is discussed within the frame work of shell model calculations in the (p1/2,g9/2) model space with emphasis on the g
9
2/2
T=0, I=1,9 pairing two-body matrix elements.Communicated by: D. Schwalm 相似文献
23.
24.
Christoph Meingast Frank Gugenberger Georg Roth Miro Haluška Hans Kuzmany 《Zeitschrift für Physik B Condensed Matter》1994,95(1):67-71
The thermal expansion of vapor-grownC
70 single crystals ahs been investigated using high-resolution capacitance dilatometry from 5–380 K. Measurements were made both parallel and perpendicular to the hexagonalc-axis. Three first-order phase transitions which we associate with the consecutive disordering of theC
70 molecules are observed upon heating at 280 K (long-axis spinning), 300 K (long-axis precession) and 355 K (quasi-free rotation), respectively. The highest-temperature transition exhibits a very large (50 K) thermal hysteresis. Powder and single-crystal X-ray diffraction show that the crystals are predominantly hexagonal-close-packed (HCP) with an idealc/a1.63 above 360 K andc/a1.84 at 295 K. 相似文献
25.
Continuing the recent work of the second author, we prove that the diophantine equation
for has exactly 12 solutions except when , when it has 16 solutions. If denotes one of the zeros of , then for we also find all with .
26.
27.
Ron M. Roth 《Designs, Codes and Cryptography》1996,9(2):177-191
Codes
of length 2
m
over {1, -1} are defined as null spaces of certain submatrices of Hadamard matrices. It is shown that the codewords of
all have an rth order spectral null at zero frequency. Establishing the connection between
and the parity-check matrix of Reed-Muller codes, the minimum distance of
is obtained along with upper bounds on the redundancy of
. An efficient algorithm is presented for encoding unconstrained binary sequences into
. 相似文献
28.
29.
30.
S. E. Arnell D. Foltescu H. A. Roth Ö. Skeppstedt A. Nilsson S. Mitarai J. Nyberg 《Zeitschrift für Physik A Hadrons and Nuclei》1993,346(2):111-117
The level structure of92Ru has been studied by means of γ-ray spectroscopy. The nucleus was produced by the58Ni(40Ca, α2p)92Ru reaction at beam energies of 147 and 187 MeV. The NORDBALL detector system including particle selection was used. A large number of new levels with excitation energies up to 11.3 MeV and spin values up to 22 or 23 units of angular momentum have been established. The level scheme is compared with recent shell model calculations using100Sn as a core. Some systematics of the g 9 2/?2 configuration is discussed and a strong correlation between the levels in90Mo and92Ru is found. 相似文献