15593532
Decay constants of heavy vector mesons in relativistic Bethe-Salpeter method
Abstract In a previous Letter, we computed the decay constants of heavy pseudoscalar mesons in the framework of relativistic (instantaneous) Bethe–Salpeter method (full 0 − Salpeter equation), in this Letter, we solve the full 1 − Salpeter equation and compute the leptonic decay constants of heavy–heavy and heavy–light vector mesons. The theoretical estimate of mass spectra of these heavy–heavy and heavy–light vector mesons are also presented. Our results for the decay constants and mass spectra include the complete relativistic contributions. We find F D s ∗ ≈ 375 ± 24 , F D ∗ ≈ 340 ± 23 ( D ∗ 0 , D ∗ ± ) , F B s ∗ ≈ 272 ± 20 , F B ∗ ≈ 238 ± 18 ( B ∗ 0 , B ∗ ± ) , F B c ∗ ≈ 418 ± 24 , F J / Ψ ≈ 459 ± 28 , F Ψ ( 2 S ) ≈ 364 ± 24 , F ϒ ≈ 498 ± 20 and F ϒ ( 2 S ) ≈ 366 ± 27 MeV .
119251875
Annihilation rate of 2++ charmonium and bottomonium
Abstract Two-photon annihilation rates of 2 + tensor charmonium and bottomonium up to third radial excited states are estimated in the relativistic Salpeter method. Full Salpeter equation for 2 + tensor state is solved with a well defined relativistic wave function and we calculated the annihilation amplitude using the Mandelstam formalism. Our estimates of the decay widths are: Γ ( χ c 2 → 2 γ ) = 501 eV , Γ ( χ c 2 ′ → 2 γ ) = 534 eV , Γ ( χ b 2 → 2 γ ) = 7.4 eV and Γ ( χ b 2 ′ → 2 γ ) = 7.7 eV . We also give total decay widths of the lowest states estimated by the two-gluon decay rates, and the results are: Γ tot ( χ c 2 ) = 2.64 MeV , Γ tot ( χ b 2 ) = 0.220 MeV and Γ tot ( χ b 2 ′ ) = 0.248 MeV .
14177196
The Layer Phase in the Non-isotropic SU(3) Gauge Model at Finite Temperature
The phase structure of a non-isotropic non-Abelian SU(3) lattice gauge model at finite temperature is investigated to the third order in the variational-cumulant expansion (VCE) approach. The layer phase exists in this model in the cases of dimensions D=4, D=5 (d=D-1).
118568245
Lepton-number violating decays of heavy mesons
The experimental observation of lepton-number violating processes would unambiguously indicate the Majorana nature of neutrinos. Various ΔL=2 processes for pseudoscalar meson M1 decays to another pseudoscalar meson M2 and two charged leptons ℓ1, ℓ2 ($M_{1}^{+}\rightarrow \ell_{1}^{+}\ell_{2}^{+}M_{2}^{-}$) have been studied extensively. Extending the existing literature on the studies of these kinds of process, we consider the rare decays of heavy mesons to a vector meson or a pseudoscalar meson. These processes have not been searched for experimentally, while they may have sizable decay rates. We calculate their branching fractions and propose to search for these decay modes in the current and forthcoming experiments, in particular at the LHCb.
119236706
Semi-Leptonic and Non-Leptonic B Meson Decays to Charmed Mesons
We study the semi-leptonic and non-leptonic B weak decays that are governed by the B → D(*) transitions. The branching ratios, CP asymmetries (CPAs) and polarization fractions of non-leptonic decays are investigated in the factorization approximation (FA). The B → D(*) form factors are estimated in the Salpeter method. Our estimation on branching ratios is in general agreement with existing experimental data. For CPAs and polarizations, comparisons among the FA results, the perturbative QCD predictions and experimental data are presented.
123969406
Semileptonic Production of Scalar and Tensor p-Wave Charmed Mesons
With the same constituents of quark and antiquark, the p-wave state has a higher mass than the corresponding s-wave state, but the relativistic corrections are much larger in the processes of which p-wave mesons are involved. Considering this, the relativistic Bethe?Salpeter method is applied to estimate the branching fractions of semileptonic decays B(s) ? D*(sJ)l? (J = 0,2). Our predictions are Br[???(2317)l?]?=?0.50%, Br[???(2573)l?]?=?0.40%, Br[B????(2400)l?]?=?0.79%, Br[B????(2460)l?]?=?0.28%, Br[???(2400)l?]?=?0.58% and Br[???(2460)l?]?=?0.27%. .
55642524
MODULATION OF LOW ENERGY BEAM TO GENERATE PREDEFINED BUNCH TRAINS FOR THE NSLS-II TOP-OFF INJECTION*
The NSLS II linac will produce a bunch train, 80-150 bunches long with 2 ns bunch spacing. Having the ability to tailor the bunch train can lead to the smaller bunch to bunch charge variation in the storage ring. A stripline is planned to integrate into the linac baseline to achieve this tailoring. The stripline must have a fast field rise and fall time to tailor each bunch. The beam dynamics is minimally affected by including the extra space for the stripline. This paper discusses the linac beam dynamics with stripline, and the optimal design of the stripline. A stripline is to be integrated in the linac to match the storage ring uniform bunch charge requirement, which simplifies the gun pulser electronics and looses the edge uniform requirement. It is located at low energy to lower the stripline power supply requirement and limit the dumped electron radiation. By turning off the stripline, the beam dynamics through linac is comparable with the baseline design. More advanced ideas can be explored. If a DC corrector along with the stripline is used, the core bunch trains gets kick from the stripline while the head and the tail of bunch train just gets amore » DC kick. The stripline power supply waveform is a single flat top waveform with fast rise and drop and the pulse length is {approx}200 ns long or 100 bunches, which may be easier from the power supply view point. We are also considering the bunch by bunch charge manipulation to match the storage ring uniform bunch charge distribution requirement. By modulating the flat top waveform at 250 MHz with adjustable amplitude, each the bunch center is either at 45 degree or 135 degree. Only the head or tail of the bunch is trimmed out. Although each bunch center deviation from idea center is very different at low energy, it is gradually minimized with beam energy increase.« less
96428988
On the transverse momentum distribution of strange hadrons produced in relativistic heavy ion collisions
Particles with strange quark content produced in the system 1.93A·GeV58Ni on58Ni have been investigated at GSI Darmstadt with the FOPI detector system. The correlation of these produced particles was analyzed with respect to the reaction plane.Λ baryons exhibit a very pronounced sideward flow pattern which is qualitatively similar to the proton flow. However, the kaon (K+,Ks0) flow patterns are significantly different from that of the protons, and their form may be useful to restrict theoretical models on the form of the kaon potential in the nuclear medium.
14727533
Transverse Kähler geometry of Sasaki manifolds and toric Sasaki-Einstein manifolds
In this paper we study compact Sasaki manifolds in view of transverse K\"ahler geometry and extend some results in K\"ahler geometry to Sasaki manifolds. In particular we define integral invariants which obstruct the existence of transverse K\"ahler metric with harmonic Chern forms. The integral invariant $f_1$ for the first Chern class case becomes an obstruction to the existence of transverse K\"ahler metric of constant scalar curvature. We prove the existence of transverse K\"ahler-Ricci solitons (or {\it Sasaki-Ricci soliton}) on compact toric Sasaki manifolds whose basic first Chern form of the normal bundle of the Reeb foliation is positive, and in particular the existence of Sasaki-Einstein metrics for compact toric Sasaki manifolds with vanishing $f_1$. We will further show that if $S$ is a compact toric Sasaki manifold such that the basic first Chern class is positive then by deforming the Reeb field we get a Sasaki-Einstein structure on $S$. As an application we obtain irregular toric Sasaki-Einstein metrics on the unit circle bundles of the powers of the anti-canonical bundle of the two-point blow-up of the complex projective plane.
119253082
Non-photonic electron-hadron correlations and non-photonic electron v2 at STAR/RHIC
Abstract Non-photonic electrons ( p T > 3 GeV / c ) represent the directions of the parent heavy quarks, and their angular correlations with charged hadrons provide a good tool to study the relative contributions from D and B meson decays in p+p collisions, as well as the flavor-dependence of the energy loss mechanism in A+A collisions. We review the disentanglement of charm and bottom contributions to non-photonic electrons in p+p collisions at s = 200 GeV at RHIC. B decay contribution is approximately 50% at the electron transverse momentum of p T > 5 GeV / c from STAR results. Incorporating the energy loss ( R AA ) information of non-photonic electrons, the result indicates a B meson suppression at high p T in heavy ion collisions. We also present non-photonic electron-hadron correlations in d+Au collisions as a baseline reference for the investigation of the heavy quark energy loss in A+A collisions. The interactions between heavy quarks and the QCD medium can lead to a non-zero “elliptic flow” parameter ( v 2 ) of D and B mesons which can be studied through v 2 of non-photonic electrons. Preliminary v 2 measurements for non-photonic electrons are shown to be lower than v 2 of charged hadrons (or K S 0 , Λ ) for 200 GeV Au+Au collisions.
118611881
A study on the relations between the topological parameter and entanglement
Abstract In this Letter, some relations between the topological parameter d and concurrences of the projective entangled states have been presented. It is shown that for the case with d = n , all the projective entangled states of two n -dimensional quantum systems are the maximally entangled states (i.e. C = 1 ). And for another case with d ≠ n , C both approach 0 when d → + ∞ for n = 2 and 3. Then we study the thermal entanglement and the entanglement sudden death (ESD) for a kind of Yang–Baxter Hamiltonian. It is found that the parameter d influences not only the critical temperature T c but also the maximum entanglement value that the system can arrive at. And we also find that the parameter d has a great influence on the ESD.