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Inspired by the newly observed state X~*(3860), we analyze the strong decay behaviors of some charmoniumlike states, X~*(3860), X(3872), X(3915), X(3930) and X(3940), with the ~3P_0 model. We carry out our work based on the hypothesis that all of these states are charmonium systems. Our analysis indicates that, as a 0~(++) charmonium state, X~*(3860) can reproduce the experimental data. As for X(3872), it can tentatively be interpreted as the mixture0 of a cc system and a D~*D~0 molecular state. If we consider X(3940) as a 3~1 S_0 state, its total width in the present work is much lower than the experimental result. Thus, the 3~1 S_0 charmonium state seems not to be a good candidate for X(3940). Furthermore, our analysis implies that it is reasonable to assign X(3915) and X(3930) to be the same state, 2~(++). However, combining our analysis with that in Refs.[14, 71], we speculate that X(3915)/X(3930) might also be the mixture of a cc system and a molecular state. 相似文献
3.
B. P. Gorshunov A. A. Boris E. S. Zhukova V. V. Zemlyanov L. S. Kadyrov S. Kaiser M. Dressel 《Journal of Experimental and Theoretical Physics》2013,116(3):460-466
The terahertz-subterahertz spectra of the complex permittivity and dynamic conductivity of polycrystalline (TMTSF)2ClO4 and (TMTSF)2PF6 samples are measured quantitatively. The spectra of (TMTSF)2ClO4 have absorption lines at frequencies of 7 and 30 cm?1. The obtained temperature dependences of the line parameters in the range 5–300 K cast some doubt on the earlier concept of their phonon origin. An excitation is detected at temperatures below 20 K in the frequency range near 30 cm?1, and its nature is related to the activation of a transverse acoustic phonon caused by the folding of the Brillouin zone due to the ordering of noncentrosymmetrical anions below 20 K. An increase in the carrier relaxation rate is found in this temperature range, which indicates a close relation between the electron and phonon subsystems in (TMTSF)2ClO4. Sings of additional low-energy excitations that should manifest themselves at frequencies below 1–2 cm?1 are detected. (TMTSF)2PF6 containing centrosymmetrical anions has no absorption lines in the frequency range 3–20 cm?1 and the temperature range 5–300 K. 相似文献
4.
Kamal K. Seth 《Progress in Particle and Nuclear Physics》2012,67(2):390-394
The experimental evidence for the exotic meson, X(3872), is summarized and the various proposed theoretical models for it are reviewed. It is pointed out that several important experimental measurements have marginal statistical significance and disagreements between different sources. Until these problems are resolved, the understanding of the structure of X(3872) is likely to remain controversial. 相似文献
5.
ZHU Shi-Lin 《理论物理通讯》2006,46(8)
We point out that the large p(p) coupling of X(1835) and the suppression of the three-body strange final states strongly indicate that X(1835) may be a p(p) baryonium. We also point out that the branching ratio of X(1835) →ηππ should be bigger than that of X(1835) →η′ππ. We suggest BES search X(1835) in the ηππ channel Finally, X(1835)may be used a tetraquark generator if X(1835) is really established as a baryonium state. 相似文献
6.
R. Lednický 《Czechoslovak Journal of Physics》1976,26(11):1242-1247
The likelihood analysis of all the production and decay information about the reaction K–pX0 is suggested, instead of the one-dimensional Adair analysis. It is shown that even the analysis of the present data could yield the likelihood ratio of the 0– and 2– hypotheses less than 10–5.The author is much grateful to V. I.Ogievetsky, V. I.Rud, W.Tybor and A. N.Zaslavsky for valuable discussions. 相似文献
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RE Baumbach X Lu F Ronning JD Thompson ED Bauer 《J Phys Condens Matter》2012,24(32):325601, 1-325601, 7
The temperature (T)-pressure (P) phase diagrams are reported for the tetragonal layered compounds CeRu(2)Al(2)B, CeRu(2)Ga(2)B, and CeRu(2)Ga(2)C, studied by magnetization, specific heat and electrical resistivity. These systems exhibit localized 4f magnetic ordering with ferromagnetic ground states at T(C)?=?12.8?K, 16.3?K, and 17.2?K, respectively. Chemical and applied pressure both increase T(C) in a similar manner. The evolution of properties with chemical and applied pressure suggests that these phase diagrams may be connected in a Doniach-like picture where CeRu(2)Al(2)B is furthest from the possible quantum phase transition and CeRu(2)Ga(2)C is the nearest. 相似文献
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《中国物理C(英文版)》2021,(9)
Recently,the LHCb Collaboration reported their observation of the first two fully open-flavor tetraquark states named Xo(2900) and X_1(2900) with unknown parity.Inspired by the report,we consider all the possible fourquark candidates for X(2900),which include the molecular structure,diquark structure,and their coupling in a chiral quark model via the Gaussian expansion method.To identify the genuine resonances,the real-scaling method(stabilization method) was employed.Our results show that five possible resonances,R_0(2914) with Γ=42 MeV,R1(2906) with Γ=29 MeV,R_1(2912) with Γ=10 McV,Rj(2920) with Γ=9 MeV,and R_J(2842) with Γ=24 MeV,originate in the cs■ system.Compared with experimental data,R_0(2914) with Γ=42 MeV may be an optimal X_0(2900) candidate.However,none of the resonances have a similar width for X_1(2900).Hence,further study is required. 相似文献
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The QCD sum rule approach is used to analyze the nature of the recently observed new resonance X (4350), which is assumed to be a diquark-antidiquark state [cs][cs] with jPC = 1-+. The interpolating current representing this state is proposed. In the calculation, contributions of operators up to dimension six are included in the operator product expansion (OPE), as well as terms which are linear in the strange quark mass ms. We find ml-+ = (4.82 ~ 0.19) GeV, which is not compatible with the X(4350) structure as a 1-+ tetraquark state. Finally, we also discuss the difference of a four-quark state's mass whether the state's interpolating current has a definite charge conjugation. 相似文献
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Using a constituent-quark model we study possible bound or resonance Nˉ states. The model fits the pˉ and pˉ cross-sections and explains the large 3
P
0 antiprotonium energy shift. Only a resonance is found in the 3
P
0
I = 0 partial wave. The threshold enhancement in the J/Ψ→γpˉ decay can be explained with FSI effects in S-waves and no Nˉ bound state is needed. 相似文献
14.
Emission spectra of the b1Sigma+(b0(+)) --> X3Sigma-(X10(+), X21) and a1Delta(a2) --> X21 transitions of AsI have been measured in the near-infrared spectral region with a Fourier-transform spectrometer. The arsenic iodide radicals were generated and excited in a fast-flow system by reaction of arsenic vapor (Asx) with iodine and microwave-discharged oxygen. The most prominent features in the spectrum are six band sequences of the strong b1Sigma+(b0(+)) --> X3Sigma-(X10(+)) transition in the range 800-900 nm. With much lower intensities the hitherto unknown b1Sigma+(b0(+)) --> X3Sigma-(X21) subsystem and the a1Delta(a2) --> X21 transition near 1660 nm are observed. Vibrational analyses have yielded improved molecular constants for the X10(+) and b0(+) states and first values of the electronic energies and vibrational constants of the X21 and a2 states (in cm-1), X21: Te = 289.8(2), omegae = 255.2(2), omegaexe = 0.68(7), a2: Te = 6305.4(3), omegae = 267.8(1), omegaexe = 0.56(2), where the numbers in parentheses are the standard deviations of the parameters. Copyright 1999 Academic Press. 相似文献
15.
A. La Magna R. Pucci 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,4(4):421-429
In this paper we have introduced a variational approach to investigate the ground state of a model which includes both the
Holstein electron-phonon interaction and the extended Hubbard electron-electron interaction. We have considered a variational
state for the phonon subsystem which generalizes the previous used forms. This state allows to take into account the possibility
of extended phonon mediated correlations. The effective electron Hamiltonian, which we have obtained, includes first and second
neighbor electron-electron interaction terms. We have treated exactly, through a Lanczos method, this effective model in the
one-dimensional case. We have applied our method to two Bechgaard salts and in these cases we have estimated the correlation
parameters. We have shown that the introduction of electron-phonon interaction allows an estimate of the on site U and nearest-neighbor V Coulomb repulsion, which are in agreement with the experimental optical spectra of the above mentioned two compounds.
Received: 30 October 1997 / Revised: 28 January 1998 / Accepted: 10 April 1998 相似文献
16.
Recent results by Belle and BABAR point to the existence of a second X particle decaying in D(0)D(0)pi(0), a few MeV above the X(3872). We identify the two X states with the neutral particles predicted by the four-quark model and show that production and decays are consistent with this assignment. We consider the yet-to-be-observed charged partners and give new hints on how to look for them. 相似文献
17.
Kakuno H Abe K Abe K Adachi I Aihara H Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banerjee S Bizjak I Bondar A Bozek A Bracko M Browder TE Chao Y Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Danilov M Dash M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Gabyshev N Garmash A Gershon T Gokhroo G Golob B Haba J Hagner C Hara T Hazumi M Higuchi I Hinz L Hokuue T Hoshi Y Hou WS Huang HC Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki Y Kang JH Kang JS Kapusta P 《Physical review letters》2004,92(10):101801
We report the measurement of an inclusive partial branching fraction for charmless semileptonic B decay and the extraction of /V(ub)/. Candidates for B-->X(u)lnu are identified with a novel X(u) reconstruction method based on neutrino reconstruction via missing 4-momentum and a technique called "simulated annealing." Based on 86.9 fb(-1) of data taken with the Belle detector, we obtain DeltaB(B-->X(u)lnu;M(X)<1.7 GeV/c2,q2>8.0 GeV2/c2)=[7.37+/-0.89(stat)+/-1.12(syst)+/-0.55(b-->c)+/-0.24(b-->u)]x10(-4) and determine |V(ub)|=[4.66+/-0.28(stat)+/-0.35(syst)+/-0.17(b-->c)+/-0.08(b-->u)+/-0.58(theory)]x10(-3). 相似文献
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《Solid State Communications》1987,61(2):101-103
The penetration depths, λ(T), of the heavy-fermion uranium-based superconductors U6X (X = Fe, Co, Mn) have been measured as a function of temperature at ∼ 35 MHz. It was found that the temperature dependence of λ(T) for these compounds agrees well with the BCS theory. However, the values of λ(0) are large. By comparing the Slater-Pauling curve of the X elements with λ(0)-1 for the U6X superconductors, we have found that λ(0)-1 is proportional to the saturation spin moments of elemental X, suggesting that there is a correlation between the superconductivity of these U6X superconductors and the magnetic nature of the X elements. 相似文献
19.
Keinosuke Hamada 《光谱学快报》2013,46(6-7):537-543
There are two possible configurations for H2O, linear(D∞h) or bent(C2v). For a C2v′, the three bands ν1′ ν2 and ν3 should appear in both Raman and infrared. For a D∞h. however, the ν1, band should appear in only Raman and the ν2 and ν3 bands, in only infrared, that is, a principle of mutual exclusion of Raman and infrared should hold. The present author concludes that H2X and D2X(X=O, S, Se, Te) have a linear D∞h. structure, since the obtained spectra show mutual exclusion of Raman and infrared. 相似文献
20.
GaAs (100)-(1X1) surface grown by molecular-beam epitaxy was studied by low energy electron diffraction (LEED). Intensities of diffraction spots were measured in the energy range of (40-300) eV and analysed using dynamical tensor LEED package. Relaxation of surface layers decreased the Pendry's R-factor to 0.48. Analysis of the LEED intensity-voltage curves for the normal electron incidence shows that the investigated surface structure is more complicated than a simply relaxed ideal surface. 相似文献