PoS - Proceedings of Science
Volume 385 - 10th International Workshop on Charm Physics (CHARM2020) - Parallel programme
Novel description of $P_c(4312)^+$, $P_c(4380)^+$, and $P_c(4457)^+$ with double triangle cusps
S. Nakamura
Full text: pdf
Pre-published on: September 15, 2021
Published on: November 10, 2021
Abstract
We propose a novel scenario for the peak structures, usually interpreted as hidden charm pentaquark ($P_c$) contributions, in the LHCb's $\Lambda_b^0\to J/\psi p K^-$ data. The key idea is to utilize leading or lower-order singularities from double triangle mechanisms. The singularities cause anomalous threshold cusps, which are significantly more singular than the ordinary ones, at the $\Sigma_c^{(*)}\bar{D}^{(*)}$ threshold. We demonstrate that the double triangle amplitudes interfere with other common mechanisms to create peak structure that fit well the $P_c(4312)^+$, $P_c(4380)^+$, and $P_c(4457)^+$ peaks in the data. This picture is completely different from commonly used ones such as hadron molecules and compact pentaquarks. Meanwhile, $P_c(4440)^+$ is included in the proposed model as a resonance with width and strength significantly smaller than previously estimated. The proposed model can (partly) explain the current data for other processes where $P_c^+$ signals are expected such as: no $P_c^+$ signals in the GlueX $J/\psi$ photoproduction data; a possible signal only from $P_c(4440)^+$ in the LHCb's $\Lambda_b^0\to J/\psi p \pi^-$ data.
DOI: https://doi.org/10.22323/1.385.0029
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.