Unraveling Proton Strangeness: Robust Determination of the Strangeness Sigma Term with High Statistical Significance

This study delves into the contribution of the strange quark within the proton, which influences several fundamental proton properties. By establishing a robust relationship between the proton's quantum anomalous energy and the sigma term, we successfully extract the strangeness sigma term ($\sigma_{sN}$) with a precise value of $420.1\pm59.3$ MeV. Additionally, we present novel results for the proton trace anomalous energy, observing a value of $0.12\pm0.02$. Our analysis integrates the most recent data from the Hall C and GlueX collaborations, warranting a strong endorsement for the existence of a non-zero strangeness component inside the proton, with a remarkable statistical significance of $7.1\sigma$. Furthermore, we investigate the possibility of scheme-independence in the extraction results and examine the uniformity of sigma terms obtained from the datasets provided by the two collaborations. Our analysis reveals compatibility between the extraction results of the respective experiments.Comment: 5 pages, 3 figures, 2 table

Mechanical structures inside proton with configurational entropy language

The structure of the proton remains a significant challenge within the field of Quantum Chromodynamics, with the origin of its spin and mass still lacking a satisfactory explanation. In this study, we utilize the gravitational form factor of the proton as the foundation for constructing the configurational entropy of the proton energy system. Employing this approach, we are able to determine key mechanical quantities such as the proton's mass radius and pressure distribution. Our analysis yields the root-mean-square mass radius of $\sqrt{\langle r_M^2\rangle}=0.720$ fm and scalar radius of $\sqrt{\langle r_S^2\rangle}=1.024$ fm for proton, which are found to be in excellent agreement with recent measurements from the Hall-C collaboration group at Jefferson Lab. Additionally, we examine the radial distribution of pressure and shear force within the proton.Comment: 6 pages, 3 figures and 1 tabl

Estimating the production of dark photons with η\eta decay in Ultra-peripheral Collisions

We propose that the signal of dark photons can be found in the decay channel of $\eta$, and that a certain number of events of dark photon leptonic decay can be observed in the double-photon collision process of heavy-ion ultra-peripheral collisions (UPC). We estimate the total cross-section for producing dark photons in ultra-peripheral $PbPb$ collisions at existing and planned future hadron colliders, as well as the number of signal events. Our results support the search for dark photon signals in ultra-peripheral $PbPb$ collisions. We consider the recent signals of $\eta$ decays produced in LHC $pp$ collisions and estimate the number of dark photon events from the same number of $\eta$ decays from CMS. Based on CMS results, we estimate that there will be at least 1000 signal events of dark photons observed for the mass $m_{A^\prime}$ less than 500 MeV. In this study, we propose a method using $\eta$ meson decay to search for signs of dark photons at heavy-ion colliders, such as LHC and RHIC.Comment: 8 pages, 5 figure

Exploring Short-Range Correlations in Symmetric Nuclei: Insights into Contacts and Entanglement Entropy

The Short-Range Correlations between nucleons in nuclei is regarded as a complex system. We investigate the relationship between the orbital entanglement entropy of SRCs $S_{ij}$ in nuclear structures and Tan contact $c_{ij}$, and find that the orbital entanglement entropies and Tan contacts corresponding to proton-proton SRC pairs and neutron-proton SRC pairs in nuclei demonstrate a scaling relation. More specifically, the proportionality of entanglement entropy between proton-proton pairs and neutron-proton pairs is directly related to the ratio of nuclear contacts within the atomic nucleus, demonstrating an approximate ratio of 2.0. Our research suggests that this scaling relationship should hold true for all symmetric nuclei, furthermore, we offer a possible explanation for this phenomenon.Comment: 8 pages, 5 figures, 1 table, accepted by PL

Trace Anomaly of Proton Mass with Vector Meson Near-Thresholds Photoproduction Data

Trace anomalous contribution to proton mass is particularly important in understanding the QCD mass structure. The value and the scale-dependent of the trace anomalous energy of the strong interaction are still not clear in combination of theories and experiments. In this paper, we explore the near-threshold photoproduction data of $\phi$ and J/$\psi$ to study the quantum anomalous energy in QCD and its scale-dependence. The vector-meson-dominance model and the van der Waals interaction between the vector meson and the proton are used. We find that the quantum anomalous energy to the proton mass is scale-dependent and it can be described as $M_a=0.25\exp(-A/\mu^2)M_N$ with $A=0.101\pm0.029$ GeV$^2$. The empirical result is consistent with the LQCD calculation at $\mu^2=4$ GeV$^2$. Finally, the corresponding evolution equation for trace anomaly part is given by our calculation.Comment: 6 pages, 4 figures, Corrected spelling mistake

A review of migrant labour rights protection in distant water fishing in Taiwan: From laissez-faire to regulation and challenges behind

Taiwan is one of the largest distant water fishing (DWF) nations worldwide. As the domestic population structure of Taiwan has changed, the domestic distant water fishery industrial labour force has gradually been replaced by migrant fishing workers. Due to the occurrence of several events in recent years and increased attention from international and domestic societies, the entire labour management system has improved. This study describes the process of change in the labour market in Taiwan’s DWF industry and several major events affecting the revision of the legal system since 2017. In addition, this study examines whether Taiwan’s institutional changes can effectively solve various types of forced labour problems by referring to the forced labour indicators established by the International Labour Organization (ILO). This study shows that Taiwan’s DWF labour market has gradually improved migrant fishing worker protection following several major events and reforms. These improvements include regulated minimum wage and working conditions on board and decreased law and regulation violations. The survey results provide insightful views regarding the government’s response to eradicate forced labour and rights protection for migrant fishing workers in DWF. These experiences provide an important lesson for DWF nations in managing the DWF labour market. When problems related to subsequent migration occur, this paper can be used as a reform direction and management direction suggestion to protect the labour rights of fishery migrant workers

4,8-Dimeth­oxy­furo[2,3-b]quinoline (γ-fagarine)

The title mol­ecule, C13H11NO3, a natural compound extracted from Phellodendron chinense, exhibits a near planar framework: the mean deviations from the furo[2,3-b]quinoline ring system and from the whole mol­ecule (not including the H atoms) are 0.006 and 0.062 Å, respectively