相关论文: Final state rescattering effects in axio-hadronic …
We report on a theoretical study of the $\pi^- p \to a^-_1(1260) p$ and $\pi^- p \to \pi^- \rho^0 p$ reactions near threshold within an effective Lagrangian approach. The production process is described by $t$-channel $\rho^0$ meson…
A search for the hadronic decays of the $h_{c}$ meson to the final states $p\bar{p}\pi^{+}\pi^{-}\pi^{0}$, $p\bar{p}\eta$, and $p\bar{p}\pi^0$ via the process $\psi(3686) \to \pi^{0}{h_c}$ is performed using $(4.48\pm0.03)\times10^{8}$…
An experimental study of the $\eta'\to \pi^0\pi^0\eta \to 6\gamma$ decay has been conducted with the best up-to-date statistical accuracy, by measuring $\eta'$ mesons produced in the $\gamma p \to \eta' p$ reaction with the A2 tagged-photon…
Modelling multiple partonic interactions in hadronic events is vital for understanding minimum-bias physics, as well as the underlying event of hard processes. A brief overview of the current Pythia 8 multiple interactions (MI) model is…
We calculate the amplitude of the rare flavour-changing neutral-current decay $B\to \pi\ell^+\ell^-$ at large recoil of the pion. The nonlocal contributions in which the weak effective operators are combined with the electromagnetic…
Light pseudoscalar resonances that couple to the Standard Model via non-renormalizable operators, such as axions and axion-like particles (ALPs), generate contributions to the renormalization group evolution equations of couplings of…
We study the effects of hadronic rescattering on hadron distributions in high-energy nuclear collisions by using an integrated dynamical approach. This approach is based on a hybrid model combining (3+1)-dimensional ideal hydrodynamics for…
It is well known that in perturbation theory existence of quasi-degenerate states can rearrange the order counting. For a heavy quarkonium system, naively, enhanced effects ($l$-changing mixing effects) could contribute already to the…
Using a sample of $4.3\times 10^5$ $\eta'\to\eta\pi^0\pi^0$ events selected from the ten billion $J/\psi$ event dataset collected with the BESIII detector, we study the decay $\eta'\to\eta\pi^0\pi^0$ within the framework of nonrelativistic…
We have investimated the effect of the isospin 1/2, J^P = 0^+ resonant state K^*_0(1950) on the decays D^0 ->\bar{K}^{0}\eta and D^0 ->\bar{K}^0 \eta' as a function of the branching ratio sum r =Br(K^*_0(1950)->\bar{K}^0\eta)+…
We study the dipion transitions $\Upsilon(4S) \rightarrow \Upsilon(nS) \pi^+\pi^-$ $(n=1,2)$. In particular, we consider the effects of the two intermediate bottomoniumlike exotic states $Z_b(10610)$ and $Z_b(10650)$ as well as bottom meson…
We show that for the S-state $\pi^0$-production in processes $\gamma+d\to d+\pi^0$ and $e^-+d\to e^-+d+\pi^0$ the rescattering effects due to the transition: $ \gamma+d\to p+p+\pi^-$ (or $n+n+\pi^+)\to d+\pi^0$ are cancelled out due to the…
We study the differential decay rate for the rare $\Lambda_b \to \Lambda (\to N \pi)\ell^+\ell^-$ transition, including a determination of the complete angular distribution, assuming unpolarized $\Lambda_b$ baryons. On the basis of a…
We revisit the production of axion-like particles (ALPs) coupled to electrons at tree-level in a relativistic plasma. We explicitly demonstrate the equivalence between pseudoscalar and derivative couplings, incorporate previously neglected…
The sign of $A_{\rm CP}(K^-\pi^+) < 0$, the evidence for $\bar B^0 \to \pi^0\pi^0$, and the possibly sizable $A_{\pi\pi}$ and $S_{\pi\pi}$ in $\bar B^0 \to \pi^+\pi^-$ all suggest that final state rescattering may be needed in $\bar B\to…
We include new additional absorption corrections into the Lebiedowicz-Szczurek (non-resonant) model for $p p \to p p \pi^+ \pi^-$ or $p \bar p \to p \bar p \pi^+ \pi^-$ processes. They are related to the $\pi N$ nonperturbative interaction…
In this work, we use the dispersion theory to provide a physical description of recent BESIII data on the reaction $ e^+ e^- \to \psi (2S) \, \pi^+ \, \pi^-$. Taking into account explicitly the effects of charged exotic intermediate states…
An amplitude analysis of an exclusive sample of 5765 events from the reaction $\pi^{-} p \to \eta^{\prime} \pi^- p$ at 18 GeV/c is described. The $\eta^{\prime} \pi^-$ production is dominated by natural parity exchange and by three partial…
The effects of plasma elemental composition and ionization state on the effective decay rate of 44Ti are investigated. We essentially follow the methods of the first authors to treat this topic, Mochizuki et al., but use more realistic…
Final state radiation in the process $e^+e^-\to\pi^+\pi^-$ is considered for the cuts used in the analysis of KLOE data at large angles. By means of a Monte Carlo event generator FEVA, effects of non-pointlike behaviour of pions are…