The $Ξ_b(6227)$ baryon with the quantum number $J^P=1/2^{-}$ is considered as a molecular state composed of a $Σ_b$ baryon and $\bar{K}$ meson. The partial decay widths of the $Σ_b\bar{K}$ molecular state into $Ξ_bγ$ and $Ξ_b^{'}γ$ final states through hadronic loops are evaluated with the help of the effective Lagrangians. The partial widths for the $Ξ_b(6227)\toγΞ_b$ and $Ξ_b(6227)\toγΞ^{'}_b$ are evaluated to be about 1.50-1.02 KeV and 17.56-24.91 KeV, respectively, which may be accessible for the LHCb. Based on our results we argue that an experimental determination of the radiative decay width of $Ξ_b(6227)$ is important for the understanding of its intrinsic properties.
The impact of final-state radiation (FSR) on the radiative return method for the extraction of the e+e- hadronic cross section is discussed in detail and experimental tests of the model dependence of FSR are proposed for the pi+pi- hadronic final state.
We investigate the observed pentaquark candidates $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$ from the latest LHCb measurement, as well as four possible spin partners in the $\bar{D}^{(*)}Σ_c^*$ system predicted from the heavy quark spin symmetry with the hadronic molecule scenarios. Similar to the previous calculation on $P_c(4380)$ and $P_c(4450)$, the partial widths of all the allowed decay channels for these $P_c$ states are estimated with the effective Lagrangian method. The cutoff dependence of our numerical results are also presented. Comparing with the experimental widths, our results sho…
This manual describes version 1.0 of the Monte Carlo event generator KROWIG for deep inelastic lepton hadron scattering at HERA. KROWIG combines the implementation of QED radiative corrections in KRONOS with the QCD parton showers and cluster fragmentation of HERWIG.
We apply a phenomenological Lagrangian approach to the radiative decay Y(4260) -> X(3872) + gamma. The Y(4260) and X(3872) resonances are considered as composite states containing both molecular hadronic and charmonium components. Having a leading molecular component in the X(3872) and a sole molecular configuration for the Y(4260) results in a prediction compatible with present data.
A short review of both theoretical and experimental aspects of the radiative return method is presented. It is emphasised that the method gives not only possibility of the independent from the scan method measurement of the hadronic cross section, but also can provide information concerning details of the hadronic interactions. New developments in the PHOKHARA event generator are also reviewed. The 3 pion and kaon pair production is implemented within the version 5.0 of the program, together with contributions of the radiative phi decays to the 2 pion final states. Missing NLO radiative correc…
Compact analytical formulae for QED radiative corrections in the processes of elastic $e-p$ scattering are obtained in the case when kinematic variables are reconstructed from the recoil proton momentum measured. Numerical analysis is presented under kinematic conditions of current experiments at JLab.
The newly observed hidden-charm meson Zc(3900) with quantum numbers J(P) = 1(+) is considered as a hadronic molecule composed of DD*. We give detailed predictions for the decay modes Zc(+) -> J/psi + pi(+) + gamma and Zc(+) -> J/psi + pi(+) + l(+) + l(-) (l = e, mu) in a phenomenological Lagrangian approach.
I discuss three B physics results with potential for exhibiting new flavour-changing interactions: (1) the time-dependent CP asymmetry in B\to J/ψK_S decay; (2) branching fractions and CP asymmetries in B\to ππ, πK decays; (3) inclusive and exclusive semi-hadronic b\to s transitions.
A numerical analysis of QED radiative corrections for elastic e(mu)p cattering in hadronic variables at energies of the current experiment at JLab is performed. The explicit formulas from the review of Akhundov et al. resulting from the integration over the phase space of leptonic variables plus photon are used to obtain the values of the cross sections and the radiative correction factor for unpolarized lepton-proton scattering. Our numerical results agree with the corresponding results arising from the formulas of Afanasev et al.
In this work, we introduce the hadronic loop contribution to explain the anomalous radiative transitions between $h_b(nP)$ and $η_b(mS)$, which was recently observed by the Belle Collaboration. Our calculation shows that the hadronic loop mechanism associated with these known decay mechanisms can explain why there exist anomalous radiative transitions between $h_b(nP)$ and $η_b(mS)$. This study deepens our understanding of the decay mechanism of higher bottomonium radiative decays.
The Lambdac(2940)+ baryon with quantum numbers J(P) = 1/2(+) is considered as a molecular state composed of a nucleon and D* meson. We give predictions for the width of the radiative decay process Lambdac(2940)+ to Lambdac(2286)+ gamma in this interpretation. Based on our results we argue that an experimental determination of the radiative decay width of Lambdac(2940)+ is important for the understanding of its intrinsic properties.
The hadronic invariant mass distribution for the process of electron-positron annihilation into a pair of charged pions accompanied by a photon radiated from the initial state has been studied for the region of DA$Φ$NE energies. The Born cross-section and the electromagnetic radiative corrections to it are calculated for realistic conditions of the KLOE detector. The dependence on the physical parameters which define the event selection is obtained.
Recently the concept of compositeness has been developed so as to distinguish whether interested hadrons are hadronic molecules or not. Here, in terms of compositeness, we investigate $\bar{K} N$ molecular structure of the $Λ(1405)$ resonance with the $Λ(1405)$ radiative decay and $K \bar{K}$ molecular structure of the $a_{0} (980)$ and $f_{0} (980)$ resonances with the $a_{0} (980)$-$f_{0} (980)$ mixing.
In the present work, we study the radiative decay of newly observed $Ξ_c(2923)^0$ based on the successful explanation that $Ξ_c(2923)^0$ is an $S$-wave $DΛ-DΣ$ molecular state in our previous study~\cite{Zhu:2020jke}. The radiative decay width of $DΛ-DΣ$ molecular state into $Ξ_c^0γ$ final state through hadronic loops are evaluated using effective Lagrangians. We find that decay width $Ξ_c(2923)^0\toΞ_c^0γ$ and $Ξ_c(2923)^0\toΞ_c^{'0}γ$ is evaluated to be approximately 1.23-11.66 KeV and 0.30-3.71 KeV, respectively. These are different from the results~\cite{Wang:2020gkn,Bijker:2020tns} that o…
We study the radiative (E1 and M1) decays of P-wave quarkonia in a strong magnetic field based on the Lagrangian of potential nonrelativistic QCD. To investigate their properties, we implement a polarized wave function basis justified in the Paschen-Back limit. In a magnetic field stronger than the spin-orbit coupling, the wave functions of the P-wave quarkonia are drastically deformed by the Hadronic Paschen-Back effect. Such deformation leads to the anisotropy of the direction of decays from the P-wave quarkonia. The analytic formulas for the radiative decay widths in the nonrelativistic lim…
We investigate the contributions of the hadronic structure of the neutron to radiative $O(αE_e/m_N)$ corrections (or the inner $O(αE_e/m_N)$ RC) to the neutron beta decay, where $α$, $E_e$ and $m_N$ are the fine-structure constant, the electron energy and the nucleon mass, respectively. We perform the calculation within the effective quantum field theory of strong low-energy pion-nucleon interactions described by the linear $σ$-model with chiral $SU(2) \times SU(2)$ symmetry and electroweak hadron-hadron, hadron-lepton and lepton-lepton interactions for the electron-lepton family with $SU(2)_L…
Radiative decays of hadronic molecules: From confusion to inspiration
Institute of Theoretical Physics, Chinese Academy of Sciences（中国科学院理论物理研究所）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）
The measurement of the hadronic cross-section in $e^+ e^-$ annihilation at high luminosity factories using the radiative return method is motivated and discussed. A Monte Carlo generator which simulates the radiative process $e^+ e^- \to γ+hadrons$ at the next-to-leading order accuracy is presented. The analysis is then extended to the description of events with hard photons radiated at very small angle.
Thermal photon emission rates from hot hadronic matter are studied to order $e^{2}g^{4}$, where $g$ indicates a strong-interaction coupling constant. Radiative decay of mesons, Compton and annihilation processes for hadrons, and bremsstrahlung reactions are all considered. Compared to the standard rates from the literature, one finds two orders of magnitude increase for low photon energies stemming mainly from bremsstrahlung and then a modest increase (factor of 2) for intermediate and high energy photons owing to radiative decays for a variety of mesons and from other reactions involving stra…
A manifestation of Kaluza-Klein picture in hadron spectra is discussed. It is argued that the experimentally observed structures in hadron spectra confirm the Kaluza-Klein picture of the world.
It is argued that radiative decays of scalars a0/f0(980) can serve as a decisive tool in establishing the nature of the latter. In particular, predictions for the widths of the radiative decays S->gamma V (S=a0/f0(980), V=omega/rho/gamma) are given in the framework of the molecule model of the scalars. Finite-range corrections are discussed in detail for the two-gamma decays of hadronic molecules, with a special attention payed to the interplay of various scales involved in the problem and to the gauge invariance of the amplitude. The results are applied to the two-photon decay of the f0(980),…
We study the role of the scalar resonances f0(1370), f0(1500) and f0(1710) in the strong and radiative three-body decays of J/psi with J/psi to V + P P (gamma gamma) and J/psi to gamma + P P (V V), where P (V) denotes a pseudoscalar (vector) meson. We assume that the scalars result from a glueball-quarkonium mixing scheme while the dynamics of the transition process is described in an effective chiral Lagrangian approach. Present data on J/psi to V + P P are well reproduced, predictions for the radiative processes serve as further tests of this scenario.
The Lambdac(2940)+ baryon with possible quantum numbers J(P) = 1/2+ and 1/2- is studied as a molecular state composed of a nucleon and D* meson. We give predictions for the strong two-body decay channels Lambdac(2940)+ to p D0, Sigmac(++) pi(-) and Sigmac(0) pi(+) where the sum of partial widths is consistent with current data for the case of J(P) = 1/2(+). The case of J(P) = 1/2(-) is shown to be ruled out.
We analyze the electromagnetic and strong decay properties of the light scalars a0(980) and f0(980) within a hadronic molecule interpretation. Both scalars are discussed within a covariant and gauge invariant model which also allows for finite size effects due to their spatially extended structure in the K Kbar-bound state picture. Allowing for f0-a0 mixing we also study its influence on the radiative decays f0/a0 to gamma gamma, f0/a0 to gamma omega, and f0/a0 to gamma rho as well as the phi production of the f0 and a0. Furthermore, we apply our formalism to describe the strong f0 to pi pi an…
Using the general form of the generalized Bethe-Salpeter wave functions for four-quark states describing the meson-meson molecular structure given in our previous work, we obtain the general formulas for the decay widths of molecular states composed of two vector mesons with arbitrary spin and parity into two photons. Then this general formalism is applied to investigate the radiative two-photon decay of the obeserved \emph{X}(3915) state, where this exotic state \emph{X}(3915) is considered as a molecular state consisting of two heavy vector mesons $D^{*0}\bar{D}^{*0}$. The numerical result o…
The O(α) electroweak radiative corrections to the process pp, ppbar\to W \to\ell^\pmν(\ell=e,μ) are calculated. The O(α) corrections can be decomposed into separately gauge invariant contributions to the W boson production and decay processes. Factorizing the collinear singularity associated with initial state photon radiation into the parton distribution functions, we find that initial state corrections have a significantly smaller effect than final state radiative corrections. We study in detail the effect of electroweak radiative corrections on a number of interesting observables: the W tra…
Intermediate hadronic meson loop contributions to $J/ψ$, $ψ^\prime \to γη_c$ ($γη_c^\prime$) are studied apart from the dominant M1 transitions in an effective Lagrangian approach. Due to the property of the unique antisymmetric tensor coupling in $V\to VP$, the hadronic loop transitions provide explicit corrections to the M1 transition amplitudes derived from the naive "quenched" $c\bar{c}$ transitions via the coupling form factors. This mechanism interfering with the M1 transition amplitudes naturally accounts for the deviations from the Godfrey-Isgur model predictions in $J/ψ$ and $ψ^\prime…
It is shown that, in the bound state picture, the $Λ_c(2593) \toΛ_cγ$ and $Λ_c(2625)\toΛ_cγ$ decays are severely suppressed. On the other hand, for their bottom counterparts, which are predicted to have masses 5900 and 5926 MeV respectively, may have significant radiative branching ratio. In particular, the $Λ_b(5926)\toΛ_bγ$ mode may even dominate over the strong decay mode. The isospin allowed $Λ^{**}_Q\toΣ_Qγ$ mode is expected to be small.
This PhD thesis studies some hadronic and radiative decays of the tau lepton using a Chiral Lagrangian including resonance fields. After a theoretical introduction, the decays to the $(πππ)^-$, $(KKπ)^-$ and $η^{(\prime)} π^- π^0$ hadronic states and $τ\to (π/K)^- γν_tau$ are analysed. Some material, which was not included in the corresponding references, is also discussed: The structure functions analysis for the 3 pion modes, the differential decay width as a function of the two-particle invariant masses in the considered three-meson modes and a simplified study of the $τ\to$η^{(\prime)} π^-…
From a theoretical point of view, there is a strong motivation to consider an MeV-scale reheating temperature induced by long-lived massive particles with masses around the weak scale, decaying only through gravitational interaction. In this study, we investigate lower limits on the reheating temperature imposed by big-bang nucleosynthesis assuming both radiative and hadronic decays of such massive particles. For the first time, effects of neutrino self-interactions and oscillations are taken into account in the neutrino thermalization calculations. By requiring consistency between theoretical…
Electron--positron annihilation into hadrons plus an energetic photon from initial-state radiation allows the hadronic cross-section to be measured over a wide range of energies at high luminosity meson factories. Weighted integrals over this cross-section are a decisive input for electroweak precision tests. A Monte Carlo event generator called PHOKHARA has been developed, which simulates $e^+ e^- \to$ hadrons + photon(s) at the NLO accuracy. The latest tests and upgrades are presented in this paper.
Based on the one state assumption of $η(1405)$ and $η(1475)$, thus, $η(1295)$ and $η(1405/1475)$ are organized as the first radial excitations of $η$ and $η'$, respectively, we investigate the productions and radiative decays of these two states in $J/ψ\to γη_X\to γγV$, where $η_X$ stands for $η(1295)$ and $η(1405/1475)$ and $V$ for vector mesons $ρ^0, \ ω, \ ϕ$. As we have learned from previous studies that the hadronic decays of these two states receive important contributions from the intermediate $\bar{K}K^*+c.c.$ meson loops due to the triangle singularity mechanism, we show that some mea…
Hadronic annihilation rate of $1^{+-}$ heavy quarkonium is given to next-to-leading order in $α_s$ and leading order in $v^2$ using a recently developed factorization formalism which is based on NRQCD. The result includes both the annihilation of P-wave color-singlet $Q\bar{Q}$ component, and the annihilation of S-wave color-octet $Q\bar{Q}$ component of the quarkonium. The notorious infrared divergences due to soft gluons, i.e., the Logarithms associated with the binding energy, encountered in previous perturbative calculations of $1^{+-}$ quarkonium decays are found to be explicitly cancelle…
The discrepancy between the PQCD calculation and the CLEO data for $χ_{c1}\to γV$ ($V=ρ^0,\,ω,\,ϕ$) stimulates our interest in exploring extra mechanism of $χ_{c1}$ decay. In this work, we apply an important non-perturbative QCD effect, i.e., hadronic loop mechanism, to study $χ_{c1}\to γV$ radiative decay. Our numerical result shows that the theoretical results including the hadronic loop contribution and the PQCD calculation of $χ_{c1}\to γV$ are consistent with the corresponding CLEO data of $χ_{c1}\to γV$. We expect further experimental measurement of $χ_{c1}\to γV$ at BES-III, which will …
A recent measurement of the total $D^{*+}$ width, $Γ_{\rm tot}(D^{*+}) = (83.3 \pm 1.3 \pm 1.4)$ keV, is shown to be close to earlier predictions based on the single-quark-transition hypothesis. Those predictions are updated using more recent masses and branching fractions to a value of 80.4 keV, with a small uncertainty associated with the radiative branching fractions of $D^{*0}$ and $D^{*+}$. A prediction for the total width of $D_2(2460)$ and its partial width into $D^* π$ and $D π$ is also updated, and found to be in agreement with experiment.
Properties of X(3872) are studied by regarding it as a $DD^{\ast}$ hadronic molecule with $J^{PC} = 2^{-+}$ in the phenomenological Lagrangian approach. We find that our model with about 97.6% isospin zero component explains the existing data nicely, for example, the ratio $\mathcal{B}(X(3872) \to J/ψπ^+π^-π^0)/\mathcal{B}(X(3872) \to J/ψπ^+π^-)$. We predict the partial widths of the radiative decays of $X(3872) \to γJ/ψ$, $γψ(2S) $ and the strong decays of $X(3872) \to J/ψπ^+ π^-$, $J/ψπ^+π^-π^0$ as well as $X(3872) \to χ_{cJ}π^0$. Our analysis shows that the measurement of the ratio $\mathca…
We study the $Z^\pm(4430)$ meson within a heavy hadron molecule interpretation where the $Z$ is considered as a bound state of a vector $D^\ast(2010)$ and an axial-vector $D_1(2420)$. We give predictions for the strong hidden-charm $Z^\pm(4430) \to π^\pm ψ$ and $π^\pmψ^\prime$ decay widths and also study the radiative $Z^\pm\;(J^P=1^-) \to π^\pmγ$ decay properties in a phenomenological Lagrangian approach. Our findings are qualitatively in line with the experimental observation that the $π^\pmψ^\prime$ transition dominates over the $π^\pmψ$ decay mode despite a smaller phase space. The width f…
We show that a simple account of hadronic high energy total cross-sections and of the observed masses and flavor-gauge-like couplings of the familiar vector mesons is obtained in a hadronic string model suggested by QCD in the limit of a large number of colors. Our picture involves a Minkowski space which in addition to the well established continuous one time and three space dimensions is endowed with an extra discrete space dimension involving a minimal 2-point lattice with spacing of order 10^{-14} cm in one of the two T-dual pictures. New mesonic states with characteristic decay modes are …
The radiative return has proven to be a competitive method for the precise measurement of the hadronic cross section, detailed studies of hadronic interactions, and even discoveries of new resonances. The most recent and future devolopments of the Monte Carlo event generator PHOKHARA are highlighted, and the impact of the radiative return measurements on the $(g-2)_μ$ puzzle is discussed.
Electron-positron annihilation into hadrons plus an energetic photon from initial state radiation allows the hadronic cross-section to be measured over a wide range of energies. The full next-to-leading order QED corrections for the cross-section for e^+ e^- annihilation into a real tagged photon and a virtual photon converting into hadrons are calculated where the tagged photon is radiated off the initial electron or positron. This includes virtual and soft photon corrections to the process e^+ e^- \to γ+γ^* and the emission of two real hard photons: e^+ e^- \to γ+ γ+ γ^*. A Monte Carlo gener…
QED radiative corrections have been calculated for leptonic and hadronic variables in parity-violating elastic ep scattering. For the first time, the calculation of the asymmetry in the elastic radiative tail is performed without the peaking-approximation assumption in hadronic variables configuration. A comparison with the PV-A4 data validates our approach. This method has been also used to evaluate the radiative corrections to the parity-violating asymmetry measured in the G0 experiment. The results obtained are here presented.
The radiative corrections of the strong and electroweak interactions are calculated for the Higgs-boson decays H -> WW/ZZ -> 4f with semileptonic or hadronic four-fermion final states in next-to-leading order. This calculation is improved by higher-order corrections originating from heavy-Higgs-boson effects and photonic final-state radiation off charged leptons. The W- and Z-boson resonances are treated within the complex-mass scheme, i.e. without any resonance expansion or on-shell approximation. The calculation essentially follows our previous study of purely leptonic final states. The elec…
We briefly discuss the recently developed probabilistic picture for in-medium jet evolution that is driven by independent multiple scatterings and branchings. These are controlled by the jet quenching parameter $\hat q$. In this framework, large radiative corrections to $p_\perp$-broadening of partons in the jet, enhanced by a double logarithm (DL) of the medium size $L$, are recovered. We argue that these non-local corrections are universal and can be reabsorbed in a renormalization of the jet quenching parameter without spoiling the probabilistic picture. As a consequence, we find that for l…
The properties of the $B_c$-meson family ($c\bar b$) are still not well determined experimentally because the specific mechanisms of formation and decay remain poorly understood. Unlike heavy quarkonia, i.e. the hidden heavy quark-antiquark sectors of charmonium ($c\bar c$) and bottomonium ($b\bar b$), the $B_c$-mesons cannot annihilate into gluons and they are, consequently, more stable. The excited $B_c$ states, lying below the lowest strong-decay $BD$-threshold, can only undergo through radiative decays and hadronic transitions to the $B_c$ ground state, which then decays weakly. As a resul…
Within the standard model, we calculate the radiative $B\rightarrow K^{\star}γ$ decay rate based on a Bethe-Salpeter description for the meson wave functions and the hadronic matrix elements. With a reasonable choice of parameters the branching ratio BR($B \rightarrow K^{\star}γ$) is found to be $(3.8-4.6)\times 10^{-5}$, which is in agreement with the CLEO experimental data. We also find with $m_{b}=5.12 GeV$ the ratio $R\equiv {Γ(B\rightarrow K^{\star}γ)}/{Γ(b\rightarrow sγ)}=(10-12)\%$, which can be slightly larger if a smaller $m_{b}$ is chosen. In this approach, the light degrees of freed…
Can one expect gamma rays rates from the QGP to be higher than from the hot hadronic gas phase? Xiong, Shuryak, Brown (XSB) calculate photon production from a hot hadronic gas via the reaction $π^- + ρ^0 \rightarrow π^- + γ$. They assume that this reaction proceeds through the a$_1$(1260). They also use their estimated a$_1$ radiative width to calculate the pion polarizability; following a connection noted previously by Holstein. However, for a$_1$(1260) $\rightarrow πγ$, the experimental radiative width is more than two times less than the value 1.4 MeV estimated and used by XSB. We describe …
Within the standard V - A theory of weak interactions, Quantum Electrodynamics (QED) and the linear sigma-model (LsM) of strong low-energy hadronic interactions we analyse gauge properties of hadronic structure of the neutron and proton in the neutron radiative beta-decay. We show that the Feynman diagrams, describing contributions of hadronic structure to the amplitude of the neutron radiative beta-decay in the tree-approximation for strong low-energy interactions in the LsM, are gauge invariant. In turn, the complete set of Feynman diagrams, describing the contributions of hadron-photon inte…
We discuss the possible interpretation of X(3872) as a $DD^{\ast}$ hadronic molecule with $J^{PC} = 2^{-+}$. Using the phenomenological Lagrangian approach, we studied its radiative and strong decay properties. We find that our model with about 97.6% isospin zero component explains the existing data nicely. We predict the partial widths of the radiative and strong decays of X(3872) and show that the measurement of the ratio $\mathcal{B}(X(3872) \to χ_{c0}π^0)/\mathcal{B}(X(3872) \to χ_{c1}π^0)$ may signal the nature of X(3872).
We critically examine the question of scaling of the Deep Inelastic Scattering process in the medium Bjorken x region on a scalar boson in the framework of the AdS/QCD correspondence. To get the right polarization structure of the forward electroproduction amplitude, we show that one needs to add (at least) the scalar to scalar and scalar to vector hadronic amplitudes. This illustrates how the partonic picture may emerge from a simple scenario based on the AdS/QCD correspondence, provided one allows the conformal dimension of the hadronic field to equal 1 and use the concept of "hadron - parto…
Thermal models have proven to be an useful and simple tool used to make theoretical predictions and data analysis in relativistic and ultra-relativistic heavy ion collisions. A new version of these models is presented here, incorporating a non equilibrium feature to the description of the intermediate fireball state formed at the chemical freeze-out. Two different effective temperatures are attributed to the expanding fireball, regarding its baryonic and mesonic sectors. The proposal is not merely to include an additional degree of freedom to reach a better adjustment to the data, but to open …
Last year, the $Ξ(1620)$ state that is cataloged in the Particle Data Group (PDG) with only one star is reported again in the $Ξ^{-}π^{+}$ final state by the Belle Collaboration. Its properties not only the spectroscopy but also the decay width cannot be simply explained in the context of conventional constituent quark models. This intrigues an active discussion on the structure of this resonance. In this work, we study the radiative decays of the newly observed $Ξ(1620)$ assuming that it is a meson-baryon molecular state of $Λ\bar{K}$ and $Σ\bar{K}$ with spin-parity $J^P=1/2^{-}$ in our previ…
The hidden-charmed pentaquark $P_c(4450)$ and the charmonium-like state $Y(4274)$ are investigated as a $\bar{D}^*Σ_c$ and a $D_s\bar{D}_{s0}(2317)$ molecular state, respectively. The spin parities of these two states cannot be well understood if only S-wave $\bar{D}^*Σ_c$ and $D_s\bar{D}_{s0}(2317)$ interactions are considered. In this work, the interactions are studied in a quasipotential Bethe-Salpeter equation approach with a partial wave decomposition on spin parity $J^P$, and the contributions of different partial waves are studied in a two-channel scattering model including a generating…
We consider a possible interpretation of the new charm-strange meson Ds0*(2317) as a hadronic molecule - a bound state of D and K mesons. Using an effective Lagrangian approach we calculate the strong Ds0* to Ds pi0 and radiative Ds0* to Ds* gamma decays. A new impact related to the DK molecular structure of the Ds0*(2317) meson is that the presence of u(d) quarks in the D and K mesons gives rise to a direct strong isospin-violating transition Ds0* to Ds pi0 in addition to the decay mechanism induced by eta-pi0 mixing considered previously. We show that the direct transition dominates over the…
A short review of both theoretical and experimental aspects of the radiative return method is presented with the emphasize on the results obtained within the EURIDICE network. It is shown that the method gives not only possibility of an independent from the scan method measurement of the hadronic cross section, but also can provide information concerning details of the hadronic interactions.
In the framework of the impact picture we compute the analyzing power $A_N$ for $pp$ elastic scattering at high energy and in the very forward direction. We consider the full set of Coulomb amplitudes and show that the interference between the hadronic non-flip amplitude and the single-flip Coulomb amplitude is sufficient to obtain a good agreement with the present experimental data. This leads us to conclude that the single-flip hadronic amplitude is small in this low momentum transfer region and it strongly suggests that this process can be used as an absolute polarimeter at the BNL-RHIC $pp…
