共查询到20条相似文献,搜索用时 76 毫秒
1.
We study the properties of D and [`(D)] \bar{{D}} mesons in hot isospin asymmetric strange hadronic matter, arising due to their interactions with the hadrons in the hyperonic
medium. The interactions of D and [`(D)] \bar{{D}} mesons with these light hadrons are derived by generalizing the chiral SU(3) model used for the study of hyperonic matter to SU(4). The nucleons, hyperons, the scalar isoscalar meson, σ and the scalar-isovector meson, d \delta as modified in the strange hadronic matter, modify the masses of D and [`(D)] \bar{{D}} mesons. It is found that, as compared to the [`(D)] \bar{{D}} mesons ([`(D0)] \bar{{D^0}}, D
−), the properties of the D mesons (D
0, D
+) are more sensitive to the isospin asymmetry at high densities. On the other hand, the effects of strangeness fraction are
found to be more dominant for the [`(D)] \bar{{D}} mesons as compared to the D mesons and these modifications are observed to be particularly appreciable at high densities. We also study the mass modifications
of the charmonium states J/ψ, ψ(3686) and ψ(3770) in the isospin asymmetric strange hadronic matter at finite temperatures and investigate the possibility of the decay
of the charmonium states into D
[`(D)] \bar{{D}} pairs in the hot hadronic medium. The mass modifications of these charmonium states arise due to their interaction with the
gluon condensates of QCD, simulated by a scalar dilaton field introduced to incorporate the broken scale invariance of QCD
within the effective chiral model. The effects of finite quark masses are taken into account in the trace of the energy momentum
tensor in QCD, while investigating the medium modification of the charmonium masses through the modification of the gluon
condensate in the medium. We also compute the partial decay widths of the charmonium states to the D
[`(D)] \bar{{D}} pairs in the hadronic medium. The strong dependence on density of the in-medium properties of the D, [`(D)] \bar{{D}} and the charmonium states, as well as the partial decay widths of charmonium states to D
[`(D)] \bar{{D}} pairs, found in the present investigation, will be of direct relevance in observables like open charm enhancement as well
as J/ψ suppression in the compressed baryonic matter (CBM) experiments at the future Facility for Antiproton and Ion Research, GSI,
where the baryonic matter at high densities is planned to be produced. 相似文献
2.
The polarizations of Λ and
[`\varLambda]{\bar{\varLambda}} are thought to retain memories of the spins of their parent s quarks and [`(s)]{\bar{s}} antiquarks, and are readily measurable via the angular distributions of their daughter protons and antiprotons. Correlations between the spins of Λ and
[`\varLambda]{\bar{\varLambda}} produced at low relative momenta may therefore be used to probe the spin states of s [`(s)]s {\bar{s}} pairs produced during hadronization. We consider the possibilities that they are produced in a 3P0 state, as might result from fluctuations in the magnitude of á[`(s)] s ?\langle {\bar{s}} s \rangle, a 1S0 state, as might result from chiral fluctuations, or a 3S1 or other spin state, as might result from production by a quark–antiquark or gluon pair. We provide templates for the p [`(p)]p {\bar{p}} angular correlations that would be expected in each of these cases, and discuss how they might be used to distinguish s [`(s)]s {\bar{s}} production mechanisms in pp and heavy-ion collisions. 相似文献
3.
Zhi-Gang Wang Zhi-Cheng Liu Xiao-Hong Zhang 《The European Physical Journal C - Particles and Fields》2009,64(3):373-386
In this article, we assume that there exist scalar D*[`(D)]*{D}^{\ast}{\bar {D}}^{\ast}, Ds*[`(D)]s*{D}_{s}^{\ast}{\bar{D}}_{s}^{\ast}, B*[`(B)]*{B}^{\ast}{\bar {B}}^{\ast} and Bs*[`(B)]s*{B}_{s}^{\ast}{\bar{B}}_{s}^{\ast} molecular states, and study their masses using the QCD sum rules. The numerical results indicate that the masses are about
(250–500) MeV above the corresponding D
*–[`(D)]*{\bar{D}}^{\ast}, D
s
*–[`(D)]s*{\bar {D}}_{s}^{\ast}, B
*–[`(B)]*{\bar{B}}^{\ast} and B
s
*–[`(B)]s*{\bar {B}}_{s}^{\ast} thresholds, the Y(4140) is unlikely a scalar Ds*[`(D)]s*{D}_{s}^{\ast}{\bar{D}}_{s}^{\ast} molecular state. The scalar D*[`(D)]*D^{\ast}{\bar{D}}^{\ast}, Ds*[`(D)]s*D_{s}^{\ast}{\bar{D}}_{s}^{\ast}, B*[`(B)]*B^{\ast}{\bar{B}}^{\ast} and Bs*[`(B)]s*B_{s}^{\ast}{\bar{B}}_{s}^{\ast} molecular states maybe not exist, while the scalar D¢*[`(D)]¢*{D'}^{\ast}{\bar{D}}^{\prime\ast}, Ds¢*[`(D)]s¢*{D}_{s}^{\prime\ast}{\bar{D}}_{s}^{\prime\ast}, B¢*[`(B)]¢*{B}^{\prime\ast}{\bar{B}}^{\prime\ast} and Bs¢*[`(B)]s¢*{B}_{s}^{\prime\ast}{\bar{B}}_{s}^{\prime\ast} molecular states maybe exist. 相似文献
4.
5.
J. Haidenbauer G. Krein U. -G. Meißner L. Tolos 《The European Physical Journal A - Hadrons and Nuclei》2011,47(2):18
A model of the DN interaction is presented which is developed in close analogy to the meson-exchange [`(K)] \bar{{K}}
N potential of the Jülich group utilizing SU(4) symmetry constraints. The main ingredients of the interaction are provided by vector meson (r \rho , w \omega exchange and higher-order box diagrams involving D
*
N , D
D \Delta , and D
*
D \Delta intermediate states. The coupling of DN to the p \pi
Lc \Lambda_{c}^{} and p \pi
Sc \Sigma_{c}^{} channels is taken into account. The interaction model generates the Lc \Lambda_{c}^{}(2595) -resonance dynamically as a DN quasi-bound state. Results for DN total and differential cross sections are presented and compared with predictions of two interaction models that are based
on the leading-order Weinberg-Tomozawa term. Some features of the Lc \Lambda_{c}^{}(2595) -resonance are discussed and the role of the near-by p \pi
Sc \Sigma_{c}^{} threshold is emphasized. Selected predictions of the orginal [`(K)] \bar{{K}}
N model are reported too. Specifically, it is pointed out that the model generates two poles in the partial wave corresponding
to the L \Lambda(1405) -resonance. 相似文献
6.
A recent experimental analysis suggested to represent the X(3872) -resonance as a c
[`(c)] \bar{{c}} 11
D
2 state but this attribution is being hotly debated. We calculate the mass values for that state by means of a previously studied
constituent-quark model. The different contributions of the model Hamiltonian to the total mass are also explicitly shown. 相似文献
7.
Estimates for electroproduction of pseudoscalar mesons at small values of skewness are presented. Cross-sections and asymmetries
for these processes are calculated within the handbag approach which is based on factorization in hard parton subprocesses
and soft generalized parton distributions (GPDs). The latter are constructed from double distributions. Transversity GPDs
are taken into account; they are accompanied by twist-3 meson wave functions. For most pseudoscalar-meson channels a combination
of ˜T and [`(E)]T \bar{{E}}_{T}^{} plays a particularly prominent role. This combination of GPDs, which we constrain by moments obtained from lattice QCD, leads,
with the exception of the p+ \pi^{+}_{} and h¢ \eta^{\prime}_{} channels, to large transverse cross-sections. 相似文献
8.
S. G. Yuan K. W. Wei J. He H. S. Xu B. S. Zou 《The European Physical Journal A - Hadrons and Nuclei》2012,48(5):61
The low-lying energy spectra of five quark systems uudc[`(c)]uudc\bar c (I = 1/2, S = 0) and udsc[`(c)]udsc\bar c (I = 0, S = 1) are investigated with three kinds of schematic interaction: the chromomagnetic interaction, the flavor-spin-dependent
interaction and the instanton-induced interaction. In all the three models, the lowest five-quark state (uudc[`(c)]uudc\bar c or udsc[`(c)]udsc\bar c) has an orbital angular momentum L = 0 and the spin-parity J
P
= 1/2−; the mass of the lowest udsc[`(c)]udsc\bar c state is heavier than the lowest uudc[`(c)]uudc\bar c state. 相似文献
9.
A model-independent analysis of anomalous gauge coupling constants of W
± bosons is presented and the corresponding restrictions on them and on the electromagnetic characteristics of W
± bosons following from the experiments on measuring the e+ e- ? W+ W- ? ( e