共查询到20条相似文献,搜索用时 46 毫秒
1.
J. Turnau 《Zeitschrift fur Physik C Particles and Fields》1984,25(3):299-302
A glueball component of theJ PC =2++ q \(\bar q\) isoscalar states is discussed within a simple mass mixing model. As the third isoscalar necessarily present in theq \(\bar q\) ?gg mixing scheme we assumeG(1410) recently claimed by ACCMOR Collaboration in the π? p→K s 0 K s 0 n data. The hypothesis is found to be compatible with the available experimental data, including two-photon decay widths and radiativeJ/ψ decays. 相似文献
2.
The fundamental mappings over carrier subspace and substructures associated with \(\{ |kq\upsilon > > \} \) augmented spin algebras of Liouville space, and their mapping onto a subduced symmetry, are derived for [A]6(L 6) spin clusters within the combinatorial context of Rota-Cayley algebra over a field. Use of suitable lexical sets of combinatorialp-tuples (number partitions) over {|IM(M 1?M n )>}M, followed by the subsequent use ofL n inner tensor product (ITP) algebra, allows the substructure of Liouville space to be derived. For SU2×L 6 mapping over the simply-reducible \(\left\{ {I\tilde H_\upsilon } \right\}\) carrier subspaces, the \(D^k \left( {\tilde U} \right) \times \tilde \Gamma ^{\left[ {\tilde \lambda } \right]} \left( \upsilon \right)\) (L 6) dual irreps, also arise as a consequence of the Liouville space recoupling termsv≡{k 1?k n } being distinct labels for \(\left\{ {I\tilde H_\upsilon } \right\}\) which are themselves amenible to combinatorial analysis within the concept of Rota-Cayley algebra. Hence, theL n -induced symmetry aspects of multiquantum NMR density matrix formalisms and their dual \(\{ |kq\upsilon :[\tilde \lambda ] > > \} \) tensorial bases of spin cluster problems are derived and the nature of the cooperative, aspect between the individual symmetries comprising the duality is demonstrated, i.e. in the context of the operator bases of Liouville space. These practical arguments correlate, well with those based on an augmented boson pattern algebra derived from a Heisenburg algebra for superoperators, ?±,?0. An earlier, treatment of conventional Hilbert space SU2×L 6 dualitycould only be realised in terms of standard SU2 boson algebra. Since the recoupling Rota-‘field’v for Liouville space is an explicit aspect of the dual mapping, a direct demonstration of cooperativity exists. 相似文献
3.
V. V. Anisovich L. G. Dakhno D. I. Melikhov V. A. Nikonov M. G. Ryskin 《Physics of Atomic Nuclei》2000,63(1):82-93
The reaction γ ⊥ * (Q 2)p→ρ ⊥ 0 p has been studied at large Q 2 and W 2/Q 2 and low momentum transfers to the nucleon, k ⊥ 2 —that is, in the region where the Pomeron exchange mechanism is operative. At sufficiently large Q 2, the Pomeron interacts with quarks occurring at small distances, whereby the hard component of the Pomeron is separated, so that the process is governed by the Pomeron of perturbative QCD (BFKL Pomeron). Our calculations indicate that, in vector-meson electroproduction at low k ⊥ 2 , the perturbative regime cannot set in fast because, for Q 2≤100 GeV2 and, accordingly, for W 2/Q 2≤107, comparatively large distances of $\rho _{q\bar q} > 0.2$ fm are important. 相似文献
4.
F. Ochiai Y. Yoshimura M. Chikawa N. Fujiwara M. Fukawa H. Kichimi E. Kohriki O. Kusumoto J. MacNaughton K. Miyano S. Noguchi Y. Noguchi T. Okusawa A. Ono T. Sato R. Sugahara A. Suzuki K. Takahashi S. Yamashita 《Zeitschrift fur Physik C Particles and Fields》1984,23(4):369-375
InclusiveK s 0 andK s 0 K s 0 production in \(\bar pp\) interactions at 3.0, 3.5, 4.0 and 4.5 GeV/c are studied. Cross sections ofK s 0 , K s 0 K s 0 andK *±(892) are presented for each incident momentum. The production ofK s 0 andK *±(892) through annihilation process is investigated. It is found that the annihilation process is dominant but decreases with incident momentum. The annihilation process is compared withe + e ? interactions. Remarkable similarity between them is found in the \({{x_0 = 2E(K_s^0 )} \mathord{\left/ {\vphantom {{x_0 = 2E(K_s^0 )} {\sqrt s }}} \right. \kern-0em} {\sqrt s }}\) distribution. Events with two detectedK s 0 's are analyzed. The result shows theK s 0 K s 0 pairs are produced in the central region of c.m. system and there is a clearS * signal in theK s 0 K s 0 effective mass distribution. 相似文献
5.
F. M. Renard 《Zeitschrift fur Physik C Particles and Fields》1979,1(2):225-227
We discuss the effects of a close degeneracy between theZ 0 and vectorQ \(\bar Q\) bound states; large mixing effects can appear modifying mainly theQ \(\bar Q\) states (widths and couplings) and leading to curious structures inside theZ peak. 相似文献
6.
Aparajita Chakraborty S. N. Banerjee 《Zeitschrift fur Physik C Particles and Fields》1985,29(3):447-452
Using the statistical model to arrive at |ψ(r)|2 the square modulus of theS state wavefunction of the neutron, the electric dipole moment |d n e | of the neutron as well as its baryon number violating lifetime have been estimated. The baryon asymmetry of the universe depending on |d n e | has also been studied in this context. 相似文献
7.
T. A. Armstrong M. Benayoun I. J. Bloodworth J. N. Carney C. J. Dodenhoff C. Evangelista B. R. French B. Ghidini M. Girone A. Jacholkowski J. Kahane J. B. Kinson A. Kirk K. Knudson V. Lenti Ph. Leruste A. Malamant J. L. Narjoux F. Navach A. Palano N. Redaelli L. Rossi M. Sené R. Sené M. Stassinaki G. Vassiliadis O. Villalobos Baillie M. F. Votruba G. Zito 《Zeitschrift fur Physik C Particles and Fields》1992,56(1):29-36
We have studied the reactions \(({{\pi ^ + } \mathord{\left/ {\vphantom {{\pi ^ + } p}} \right. \kern-0em} p})p \to ({{\pi ^ + } \mathord{\left/ {\vphantom {{\pi ^ + } p}} \right. \kern-0em} p})(K\bar K\pi )p\) where the \(K\bar K\pi \) system is centrally produced, at 85 GeV/c and 300 GeV/c using the CERN Omega spectrometer. A spin-parity analysis of theK S 0 K ± π ? system shows the presence of a strongJ PC=1++ signal which we identify as theE/f 1 (1420) meson. We also find evidence for the decayE/f 1(1420)→K S 0 K S 0 π 0 which determines theC-parity of this state to be positive. Alternative explanations of the data have been tested and ruled out. Hence we obtain the quantum numbers of theE/f 1 (1420) to beI G(JPC)=0+(1+). 相似文献
8.
Ph. Gavillet R. Armenteros M. Aguilar-Benítez M. Mazzucato C. Dionisi 《Zeitschrift fur Physik C Particles and Fields》1982,16(2):119-128
Evidence is presented for a newK * \(\bar K\) +c.c. resonance with a mass of (1,526±6) MeV, a width of (107±15) MeV and quantum numbersIJ PC=01++. We call itD′ meson. Initially it is observed as aK * \(\bar K\) +c.c. enhancement in the reactionsK ? p→(K s 0 K ±π?)Λ at 4.2 GeV/c. The isospin assignmentI=0 comes from its further observation in the reactionsK ? p→(K s 0 K ±π?)Σ 0 andK ? p→(K s 0 K ±π?)Σ(1,385)0 but not inK ? p→(K + K ?π?)Σ+ orK ? p→(K s 0 K ±π?)Σ(1,385)+. A maximum likelihood analysis of the (K \(\bar K\) π) decay Dalitz plots in the reactionsK ? p→(K s 0 K ±π?) determines theJ PC of theD′ meson to be 1++. A satisfactorySU(3) fit is obtained to a 1++ nonet composed of theI-1A 1, theI=1/2Q A with theD(1,285) and theD′(1,526) as theI=0 members having a mixing angle close to the magic one. 相似文献
9.
K. Freitag K. Krien J. C. Soares P. Herzog W. D. Schneider E. Bodenstedt 《Zeitschrift für Physik A Hadrons and Nuclei》1977,282(1):39-48
Byγ- e K ? ande K ? -γ TDPAC measurements with the 133 keV–482 keV cascade of181Ta in a polycrystalline beryllium matrix theA 2(e K ? )-coefficient of the 482 keV transition was determined as: A2(482e K ? )=?0.095±0.015. The theoretical value is 6.0 times larger. A remeasurement of the E2/M1 mixing ratio of the same transition by integralγ- γ angular correlation measurements with a system of three 20 ccm Ge(Li)-detectors gave the result:δ(482)=4.96±0.25. Theα K -coefficient was redetermined as:α K (482)=0.0246±0.0018. From these data the penetration parameter:λ=157±11 is derived and compared with previously published values and theoretical estimates. 相似文献
10.
11.
I. V. Ajinenko Y. A. Belokopitov A. A. Borovikov P. V. Chliapnikov Z. C. Garutchava L. N. Gerdyukov S. A. Gumenuk V. V. Kniazev A. I. Kurnosenko L. V. Orekhova L. P. Petrovikh V. N. Riadovikov A. G. Tomaradse V. A. Uvarov A. P. Vorobjev N. S. Amaglobely Ch. S. Chochiachvili M. Barth E. A. De Wolf M. Van Immerseel F. Verbeure CERN - USSR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1984,25(2):103-114
We present final results on inclusive production ofK *+(890),K *+(1430) andK *?(890) in \(\bar K^ + p\) interactions at 32 GeV/c, based on a statistics of ~27 events/μb. Total cross sections,p T -andx-dependence of inclusive distributions are compared with experiments at other energies and with the Lund fragmentation model. Spin density matrix elements of theK *+(890) are also discussed. The results suggest that “recombination” of both initial state valence quarks \(\bar s\) andu of theK + intoK *+(890), responsible in the Lund model for ~45% of theK *+(890) cross section, is strongly suppressed. 相似文献
12.
A simpleππ, $\bar K$ K, andρρ(ωω) fully coupled channel model is proposed to predict the isoscalarS-wave phase shifts and inelasticities forππ scattering in the 1.0 to 2.0 GeV region. TheS- matrix is required to exhibit poles corresponding to the established isoscalarJ π=0+ resonancesf 0(975),f 0(1400), andf 0(1710). A dominant feature of the experimentalππ inelasticity is the clear opening of the $\bar K$ K channel near 1 GeV, and the opening of another channel in the 1.4–1.5 GeV region. The success of our model in predicting this observed dramatic energy dependence indicates that the effect of multipion channels is adequately described by theππ coupling to the $\bar K$ K channel, theρρ(4π) andωω(6π) channels. 相似文献
13.
Based on the conserved-vector-current (CVC) hypothesis and a four-ρ-resonance unitary and analytic VMD model of the pion electromagnetic form factor, theσ tot(E v lab ) and dσdE π lab of the weak \(\bar v_e e^ - \to \pi ^ - \pi ^0\) process are predicted theoretically for the first time. Their experimental approval could verify the CVC hypothesis for all energies above the two-pion threshold. Since, unlike the electromagnetic e+e?→π+π? process, there is no isoscalar vector-meson contribution to the weak \(\bar v_e e^ - \to \pi ^ - \pi ^0\) reaction, accurate measurements of theσ tot(E v lab ) that moreover is strengthened with energyE v lab linearly could solve now a widely discussed problem of the mass specification of the first excited state of theρ(770) meson. As a by-product, an equality \(\sigma _{tot} (\bar v_e e^ - \to \pi ^ - \pi ^0 ) = \sigma _{tot} (e^ + e^ - \to \pi ^ - \pi ^0 )\) is predicted for \(\sqrt s \approx 70 GeV\) . 相似文献
14.
Hadron temperatures ofe + e ?→h \(\bar h\) from PEP experiments at 29 GeV are estimated using theP ⊥ distribution; rather small fluctuations are found for temperatures of π,K,..., Ξ with respect to the average \(\bar T = 196 \pm 7\) MeV. A semi-empirical formula including quark content ofh is proposed to account for multiplicities of π,K, ..., Δ in terms of a unique temperature \(\bar T\) . The formula is further extended to charmed particlesD, F, J/Ψ andΛ c without free parameters. The property \(\bar T\) ~E cm 1/4 holds for other experiments of DESY andCESR. 相似文献
15.
L. Ricken D. Bohle G. Domogala K. Glasner E. Kuhlmann 《Zeitschrift für Physik A Hadrons and Nuclei》1982,306(1):67-71
Electric quadrupole transition strengths for the 2 1 + ,T=1→0 1 + ,T=1γ-decay branches are summarized for 10≦A≦42 nuclei. In10B the corresponding branch has been remeasured by use of the9Be(p, γ)10B resonance reaction atE p =320 keV; an upper limit of 0.6% is found. The variation of theE2 strengths within each individualT=1 isobaric multiplet reveals the particleor hole-character of the levels involved. The isoscalar 2 1 + →0 1 + transition strengths in 10≦A≦48 nuclei vary between 2 and 20 Weißkopf units showing drastic shell effects. Results for the ratio of neutron and proton matrix elements deduced from analogγ-decay studies and from inelastic pion scattering are compared. 相似文献
16.
John C. Wolfe 《Communications in Mathematical Physics》1975,44(1):53-72
The groupG of unitary elements of a maximal abelian von Neumann algebra on a separable, complex Hilbert spaceH acts as a group of automorphisms on the CAR algebraA(H) overH. It is shown that the set ofG-invariant states is a simplex, isomorphic to the set of regular probability measures on aw*-compact setS ofG-invariant generalized free states. The GNS Hilbert space induced by an arbitraryG-invariant state onA(H) supports a *-representation ofC(S); the canonical map ofA(H) intoC(S) can then be locally implemented by a normal,G-invariant conditional expectation. 相似文献
17.
18.
The purpose of this paper is to study the so-calledspectral class Q of anharmonic oscillatorsQ=?D 2+q having the same spectrum λ n =2n (n≧0) as the harmonic oscillatorQ 0=?D 2+x 2?1. Thenorming constants \(t_n = \mathop {\lim }\limits_{x \uparrow \infty } \ell g[( - 1)^n {{e_n (x)} \mathord{\left/ {\vphantom {{e_n (x)} {e_n }}} \right. \kern-0em} {e_n }}( - x)]\) of the eigenfunctions ofQ form a complete set of coordinates inQ in terms of which the potential may be expressed asq=x 2?1?2D 2 ?g? with $$\theta = \det \left[ {\delta _{ij} + (e^{ti} - 1)\int\limits_x^\infty {e_i^0 e_j^0 :0 \leqq i,j,< \infty } } \right],$$ e n 0 being then th eigenfunctionQ 0. The spectrum and norming constants are canonically conjugate relative to the bracket [F, G]=∫ΔFDΔGdx,to wit: [λ i , λj=0, [t i, 2λ j ]=1 or 0 according to whetheri=j or not, and [t i,t j]=0. This prompts an investigation of the symplectic geometry ofQ. The function ? is related to the theta function of a singular algebraic curve. Numerical results are also presented. 相似文献
19.
P. Collet J. -P. Eckmann V. Glaser A. Martin 《Communications in Mathematical Physics》1984,94(3):353-370
We study the iterations of the mapping $$\mathcal{N}[F(s)] = \frac{{(F(s))^2 - (F(0))^2 }}{s} + (F(0))^2 ,$$ with the constraintsF(1)=1,F(s)=∑a nsn,a n≧0, and find that, except ifF(s)≡s,N[F(s)] approaches either 0 or 1 for |s|<1 ask→∞. 相似文献
20.
Matteo Cacciari Gavin P. Salam Gregory Soyez 《The European Physical Journal C - Particles and Fields》2012,72(3):1-54
FastJet is a C++ package that provides a broad range of jet finding and analysis tools. It includes efficient native implementations of all widely used 2??1 sequential recombination jet algorithms for pp and e + e ? collisions, as well as access to 3rd party jet algorithms through a plugin mechanism, including all currently used cone algorithms. FastJet also provides means to facilitate the manipulation of jet substructure, including some common boosted heavy-object taggers, as well as tools for estimation of pileup and underlying-event noise levels, determination of jet areas and subtraction or suppression of noise in jets. 相似文献