119430774
A study of correlation between the oscillation amplitude and stellar parameters of delta Scuti stars in open clusters - Toward selection rules for delta Scuti star oscillations
In the present work, we study correlations between stellar fundamental parameters and the oscillation amplitude for Scuti stars. We present this study for a sample of 17 selected Scuti stars belonging to 5 young open clusters. Taking advantage of properties of Scuti stars in clusters, we correct the photometric parameters of our objects for the eects of fast rotation. We confirm the benefit of applying such corrections in this kind of studies. In addition, the technique used for this correction allows us to obtain an estimate of stellar parameters such as the angle of inclination and the rotation rate, usually not accessible. A significant correlation between the parameter i 0 (estimation of the angle of inclination of the star) and the oscillation amplitude is found. A discussion and interpretation of these a priori surprising results is proposed, in terms of a possible selection rule for oscillation modes of Scuti stars.
120492049
Octupole degree of freedom for nuclei near 152Sm in a reflection-asymmetric relativistic mean-field approach
The potential energy surfaces of even-even isotopes near 152Sm are investigated within the constrained reflection-asymmetric relativistic mean-field approach using parameter sets PK1 and NL3. It is shown that the critical-point candidate nucleus 152Sm marks the shape/phase transition not only from U(5) to SU(3) symmetry, but also from the octupole deformed ground state in 150Sm to the quadrupole deformed ground state in 154Sm. The important role of the octupole deformation driving pair (?2f7/2, ?1i13/2) is demonstrated based on the components of the single-particle levels near the Fermi surface. In addition, the patterns of both the proton and the neutron octupole deformation driving pairs (?2f7/2, ?1i13/2) and (?2d5/2, ?1h11/2) are investigated.
33315431
Spin structure of nucleons in a quark model with constituent gluons.
101147336
Impedance Computation of Main Components in CSNS/RCS
16718501
The Kaon-Photoproduction Of Nucleons In The Chiral Quark Model
In this paper, we develop a general framework to study the mesonphotoproductions of nucleons in the chiral quark model. The S and U channel resonance contributions are expressed in terms of the ChewGoldberger-Low-Nambu (CGLN) amplitudes. The kaon-photoproduction processes, γp → K+Λ, γp → K+Σ0, and γp → K0Σ+, are calculated. The initial results show that the quark model provides a much improved description of the reaction mechanism for the kaon-photoproductions of the nucleon with less parameters than the traditional phenomenological approaches. PACS numbers: 13.75.Gx, 13.40.Hq, 13.60.Le,12.40.Aa
119334067
Longitudinal transitions of baryon resonances in the constituent quark model
A longitudinal transition operator that satisfies the gauge invariance requirement is introduced in the constituent quark model. The corresponding longitudinal transitions from the ground state of the nucleon to resonances of the baryon are calculated. The study shows that the longitudinal coupling plays an important role in the understanding of the structure of the baryon.
118596197
Discriminating Higgs production mechanisms using jet energy profiles
We present a new tool for precision measurements of the Higgs boson production mechanisms at the LHC. We study events with a Higgs boson produced with two forward jets. Even with fairly stringent cuts, one expects a significant contamination of gluon fusion (GF) in addition to vector-boson fusion (VBF) in the event sample. By measuring the jet energy profile of the most central jet, we find that SM production can be distinguished from either pure VBF or pure GF at the 5 sigma level with 100 fb(-1) of luminosity at the 14 TeV LHC. Moreover, this discrimination technique can be used to validate or rule out new physics models that predict similar observable branching fractions as the 125 GeV Standard Model Higgs boson but have different production mechanisms.
15695185
Systematic study on QCD interactions of heavy mesons with ρ meson
Abstract The strong interactions of the negative-parity heavy mesons with ρ meson may be described consistently in the context of an effective Lagrangian, which is invariant under isospin SU ( 2 ) transformation. Four coupling constants g H H ρ , f H ∗ H ρ , g H ∗ H ∗ ρ and f H ∗ H ∗ ρ enter the effective Lagrangian, where H ( H ∗ ) denotes a pseudoscalar bottom or charm meson (the corresponding vector meson). Using QCD light cone sum rule (LCSR) method and, as inputs, the hadronic parameters updated recently, we give an estimate of g H ∗ H ∗ ρ and f H ∗ H ∗ ρ , about which little was known before, and present an improved result for g H H ρ and f H ∗ H ρ . Also, we examine the heavy quark asymptotic behavior of these nonperturbative quantities and assess the two low energy parameters β and λ of the corresponding effective chiral Lagrangian.
14686196
Importance of Higher Twist Effects to Understand Charmed Color-Suppressed $B$ Decays
Working within the framework of the QCD light cone sum rules (LCSR), we compute and discuss the nonfactorizable higher twist effect in $\bar{B}^0\to D^{*0}\pi^0$ to make an all-around examination of its role in the charmed color-suppressed B decays. Analogously to the case of $\bar{B}^0\to D^{0}\pi^0$, such effect turns out to be of the same strong phase as the factorizable amplitude, and modifies constructively the magnitude by order $(40-90)%$ so that the effective coefficient $a_2^{f}=C_1+C_2/3$ receives a positive correction comparable numerically with it. Nonleading as the soft effect in question is, our findings for it, along with the previous LCSR analyses of $\bar{B}^0\to D^{0}\pi^0$, are suggestive of the dominance of soft exchanges in these charmed color suppressed B decays. Also, the emphases are put on importance of understanding intensively various related higher twist and transverse momentum effects to interpret the data on $B \to D^{0(*0)}(\pi^0,\eta,\eta'),J/\psi K^{(*)}$.
119441908
Dynamical isospin effects in nucleon-induced reactions
The isospin effects in proton-induced reactions on isotopes of $^{112\ensuremath{-}132}\mathrm{Sn}$ and the corresponding $\ensuremath{\beta}$-stable isobars are studied by means of the improved quantum molecular dynamics model and some sensitive probes for the density dependence of the symmetry energy at subnormal densities are proposed. The beam energy range is chosen to be 100\char21{}300 MeV. Our study shows that the system size dependence of the reaction cross sections for $p+{}^{112\ensuremath{-}132}\mathrm{Sn}$ deviates from the Carlson's empirical expression obtained by fitting the reaction cross sections for proton on nuclei along the $\ensuremath{\beta}$-stability line and sensitively depends on the stiffness of the symmetry energy. We also find that the angular distribution of elastic scattering for $p+{}^{132}\mathrm{Sn}$ at large impact parameters is very sensitive to the density dependence of the symmetry energy, which is uniquely due to the effect of the symmetry potential with no mixture of the effect from the isospin dependence of the nucleon-nucleon cross sections. The isospin effects in neutron-induced reactions are also studied and it is found that the effects are just opposite to that in proton-induced reactions. We find that the difference between the peaks of the angular distributions of elastic scattering for $p+{}^{132}\mathrm{Sn}$ and $n+{}^{132}\mathrm{Sn}$ at ${E}_{p,n}=100$ MeV and $b=7.5$ fm is positive for soft symmetry energy ${U}_{\mathrm{sym}}^{\mathrm{sf}}$ and negative for super-stiff symmetry energy ${U}_{\mathrm{sym}}^{\mathrm{nlin}}$ and close to zero for linear density dependent symmetry energy ${U}_{\mathrm{sym}}^{\mathrm{lin}}$, which seems very useful for constraining the density dependence of the symmetry energy at subnormal densities.
122278849
Neutron star structure with modern nucleonic three-body forces
We provide convenient parametrizations of the high-density nuclear equation of state obtained within the Brueckner-Hartree-Fock approach using different modern nucleon-nucleon potentials together with compatible microscopic nuclear three-body forces. The corresponding neutron star mass-radius relations are also presented.