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41.
J. Domscheit S. Trmnen B. Aengenvoort H. Hübel R. A. Bark M. Bergstrm A. Bracco R. Chapman D. M. Cullen C. Fahlander S. Frattini A. Grgen G. B. Hagemann A. Harsmann B. Herskind H. J. Jensen S. L. King S. Lenzi D. Napoli S. W.
degrd C. M. Petrache H. Ryde U. J. van Severen G. Sletten P. O. Tjm C. Ur 《Nuclear Physics A》1999,660(4):1211-392
High-spin states in 163Lu have been investigated using the Euroball spectrometer array. The previously known superdeformed band has been extended at low and high energies, and its connection to the normal-deformed states has been established. From its decay the mixing amplitude and interaction strength between superdeformed and normal states are derived. In addition, a new band with a similar dynamic moment of inertia has been found. The experimental results are compared to cranking calculations which suggest that the superdeformed bands in this mass region correspond to shapes with a pronounced triaxiality (γ≈±20°). 相似文献
42.
H. W. Schffer P. H. Mokler R. W. Dunford C. Kozhuharov A. Krmer A. E. Livingston T. Ludziejewski H. -T. Prinz P. Rymuza L. Sarkadi Z. Stachura Th. Sthlker P. Swiat A. Warczak 《Physics letters. A》1999,260(6):331-494
The photon energy differential shape of the second order matrix element for the two-photon (2E1) decay of the 1s2s1S0 level in He-like gold has been measured. The results are in agreement with a recent fully relativistic calculation. The corresponding 2E1 matrix element deviates from those in lighter He-like systems due to the strong central field in a heavy two-electron ion. 相似文献
43.
44.
Kerdock codes (Kerdock, Inform Control 20:182–187, 1972) are a well-known family of non-linear binary codes with good parameters
admitting a linear presentation in terms of codes over the ring (see Nechaev, Diskret Mat 1:123–139, 1989; Hammons et al., IEEE Trans Inform Theory 40:301–319, 1994). These codes have been
generalized in different directions: in Calderbank et al. (Proc Lond Math Soc 75:436–480, 1997) a symplectic construction
of non-linear binary codes with the same parameters of the Kerdock codes has been given. Such codes are not necessarily equivalent.
On the other hand, in Kuzmin and Nechaev (Russ Math Surv 49(5), 1994) the authors give a family of non-linear codes over the
finite field F of q = 2
l
elements, all of them admitting a linear presentation over the Galois Ring R of cardinality q
2 and characteristic 22. The aim of this article is to merge both approaches, obtaining in this way new families of non-linear codes over F that can be presented as linear codes over the Galois Ring R. The construction uses symplectic spreads.
相似文献
45.
The Friedberg–Lee (FL) symmetry is generated by a transformation of a fermionic field q to q+ξz. This symmetry puts very restrictive constraints on allowed terms in a Lagrangian. Applying this symmetry to N fermionic fields, we find that the number of independent fields is reduced to N−1 if the fields have gauge interaction or the transformation is a local one. Using this property, we find that a seesaw model originally with three generations of left- and right-handed neutrinos, with the left-handed neutrinos unaffected but the right-handed neutrinos transformed under the local FL translation, is reduced to an effective theory of minimal seesaw which has only two right-handed neutrinos. The symmetry predicts that one of the light neutrino masses must be zero. 相似文献
46.
We study algebraic geometric codes obtained from rational normal scrolls. We determine the complete weight hierarchy and spectrum
of these codes.
相似文献
47.
HUANG Hai-Ping 《理论物理通讯》2015,63(1):115-124
The statistical physics properties of low-density parity-check codes for the binary symmetric channel are investigated as a spin glass problem with multi-spin interactions and quenched random fields by the cavity method. By evaluating the entropy function at the Nishimori temperature, we find that irregular constructions with heterogeneous degree distribution of check(bit) nodes have higher decoding thresholds compared to regular counterparts with homogeneous degree distribution. We also show that the instability of the mean-field calculation takes place only after the entropy crisis, suggesting the presence of a frozen glassy phase at low temperatures. When no prior knowledge of channel noise is assumed(searching for the ground state), we find that a reinforced strategy on normal belief propagation will boost the decoding threshold to a higher value than the normal belief propagation. This value is close to the dynamical transition where all local search heuristics fail to identify the true message(codeword or the ferromagnetic state). After the dynamical transition, the number of metastable states with larger energy density(than the ferromagnetic state)becomes exponentially numerous. When the noise level of the transmission channel approaches the static transition point, there starts to exist exponentially numerous codewords sharing the identical ferromagnetic energy. 相似文献
48.
1 Introduction Moderndigitalcommunicationsystemsoftenrequireerror freetransmission .Errorcontrolcodingtechnologyhasbeenusedwidelyincommunicationsystem .Andithasbeenimprovingtheperformanceofcommunicationsystem greatly ,especiallyinwirelesscommunicationss… 相似文献
49.
当信息在第二类窃密信道中传输时,线性码的广义汉明重量谱完全描述的它在该信道中的密码学特征.计算一个线性码的广义汉明重量谱是一个基本问题,首先提出了线性码的“最简基”的概念.在此基础上给出了一般线性码子码的几种计数公式,并给出了它们之间等价性的证明. 相似文献
50.
The rank of a q-ary code C is the dimension of the subspace spanned by C. The kernel of a q-ary code C of length n can be defined as the set of all translations leaving C invariant. Some relations between the rank and the dimension of the kernel of q-ary 1-perfect codes, over
as well as over the prime field
, are established. Q-ary 1-perfect codes of length n=(qm − 1)/(q − 1) with different kernel dimensions using switching constructions are constructed and some upper and lower bounds for the dimension of the kernel, once the rank is given, are established.Communicated by: I.F. Blake 相似文献