Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userPhotoproduction of hidden-bottom pentaquark and related topics
67
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
Due to the discovery of the hidden-charm pentaquark $P_c$ states by the LHCb collaboration, the interests on the candidates of hidden-bottom pentaquark $P_b$ states are increasing. They are anticipated to exist as the analogues of the $P_c$ states in the bottom sector and predicted by many models. We give an exploration of searching for a typical $P_b$ in the $gamma p to Upsilon p$ reaction, which shows a promising potential to observe it at an electron-ion collider. The possibility of searching for $P_b$ in open-bottom channels are also briefly discussed. Meanwhile, the $t$-channel non-resonant contribution, which in fact covers several interesting topics at low energies, is systematically investigated.
rate research
Read More
Recently BESIII collaboration discovered a charged strange hidden-charm state $Z_{cs}$(3985) in the $D_s^-D^{*0} + D_s^{*-}D^{0}$ spectrum. A higher $Z_{cs}$ state coupling to $bar{D}_s^{*-}D^{*0}$ is expected by SU(3)-flavor symmetry, and their bottom partners are anticipated by heavy quark flavor symmetry. Here we study the photoproduction of these exotic states and investigate carefully the background from Pomeron exchange. Our results indicate that the maximal photoproduction cross section of strange partner is around 1 $sim$ 2 orders of magnitude smaller than that of the corresponding non-strange states. The possibility of searching for them in future electron-ion colliders (EIC) is briefly discussed.
The mass spectrum of hidden charm pentaquark states composed of two diquarks and an antiquark are calculated by use of an effective Hamiltonian which includes explicitly the spin, color, and flavor dependent interactions. The results show that the $P_c(4312)^+$ and $P_c(4440)^+$ states could be explained as hidden charm pentaquark states with isospin and spin-parity $IJ^P=1/2left(3/2^-right)$, the $P_c(4457)^+$ state could be explained as a hidden charm pentaquark state with $IJ^P=1/2left(5/2^-right)$, and the $P_{cs}(4459)^+$ state could be explained as a hidden charm pentaquark state with $IJ^P=0left(1/2^-right)$ or $0left(3/2^-right)$. Predications for the masses of other possible pentaquark states are also given, and the possible decay channels of these hidden charm pentaquark states are discussed.
A large variety of periodic tables of the chemical elements have been proposed. It was Mendeleev who proposed a periodic table based on the extensive periodic law and predicted a number of unknown elements at that time. The periodic table currently used worldwide is of a long form pioneered by Werner in 1905. As the first topic, we describe the work of Pfeiffer (1920), who refined Werners work and rearranged the rare-earth elements in a separate table below the main table for convenience. Todays widely used periodic table essentially inherits Pfeiffers arrangements. Although long-form tables more precisely represent electron orbitals around a nucleus, they lose some of the features of Mendeleevs short-form table to express similarities of chemical properties of elements when forming compounds. As the second topic, we compare various three-dimensional helical periodic tables that resolve some of the shortcomings of the long-form periodic tables in this respect. In particular, we explain how the 3D periodic table Elementouch (Maeno 2001), which combines the s- and p-blocks into one tube, can recover features of Mendeleevs periodic law. Finally we introduce a topic on the recently proposed nuclear periodic table based on the proton magic numbers (Hagino and Maeno 2020). Here, the nuclear shell structure leads to a new arrangement of the elements with the proton magic-number nuclei treated like noble-gas atoms. We show that the resulting alignments of the elements in both the atomic and nuclear periodic tables are common over about two thirds of the tables because of a fortuitous coincidence in their magic numbers.
The production of hidden-bottom pentaquark $P_{b}$ states via $gamma p$ and $pi ^{-}p$ scatterings is studied within an effective Lagrangian approach and the vector-meson-dominance mechnism. For the $P_{b}$ production in the process $gamma prightarrow Upsilon p$, the dipole Pomeron model is employed to calculate the background contribution, and the experimental data can be well described. For the process $pi ^{-}prightarrow Upsilon n$, the Reggeized $t$-channel with $pi $ exchange is considered as the main background for the $P_{b}$ production. Near the threshold, two-peak structure from the states $P_{b (11080)$ and $P_{b}(11125)$ can be observed if energy bin width is chosen as 0.01 GeV, and the same result is obtained in the $pi ^{-}p$ scattering. Moreover, by taking the branching ratio of Br$[{P_{b}rightarrow pi N}]simeq 0.05%$, the numerical result shows that the average value of cross section from the $P_{b}(11080)$ state produced in the $gamma p$ or $pi ^{-}p$ scattering reaches at least 0.1 nb with a bin of 0.1 GeV. Even if we reduce the branching ratio of the $P_{b}$ state into $pi N$ channel by one order, the theoretical average of the cross section from $P_{b}(11080)$ production in $pi ^{-}p$ scattering can reach the order of 0.01 nb with a bin of 0.1 GeV, which means that the signal can still be clearly distinguished from the background. The experimental measurements and studies on the hidden-bottom pentaquark $P_{b}$ state production in the $gamma p $ or $pi ^{-}p$ scattering near-threshold energy region around $Wsimeq 11$ GeV are strongly suggested, which are accessible at COMPASS and JPARC. Particularly, the result of the photoproduction suggests that it is very promising to observe the hidden-bottom pentaquark at proposed EicC facility in China.
We study the three-body systems of $bar{K}^{(*)}B^{(*)}bar{B}^{(*)}$ by solving the Faddeev equations in the fixed-center approximation, where the light particle $bar{K}^{(*)}$ interacts with the heavy bound states of $Bbar{B}$ ($B^*bar{B}^*$) forming the clusters. In terms of the very attractive $bar{K}^*B$ and $bar{K}^*B^*$ subsystems, which are constrained by the observed $B_{s1}(5830)$ and $B_{s2}^*(5840)$ states in experiment, we find two deep bound states, containing the hidden-bottom components, with masses $11002pm 63$ MeV and $11078pm 57$ MeV in the $bar{K}^*Bbar{B}$ and $bar{K}^*B^*bar{B}^*$ systems, respectively. The two corresponding states with higher masses of the above systems are also predicted. In addition, using the constrained two-body amplitudes of $bar{K}B^{(*)}$ and $bar{K}bar{B}^{(*)}$ via the hidden gauge symmetry in the heavy-quark sector, we also find two three-body $bar{K}Bbar{B}$ and $bar{K}B^{*}bar{B}^*$ bound states.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
