Analytical theory of coherent synchrotron radiation wakefield of short bunches shielded by conducting parallel plates

We develop a general model of coherent synchrotron radiation (CSR) impedance with shielding provided by two parallel conducting plates. This model allows us to easily reproduce all previously known analytical CSR wakes and to expand the analysis to the situations not explored before. It reduces calculations of the impedance to taking integrals along the trajectory of the beam. New analytical results are derived for the radiation impedance with shielding for the following orbits: a kink, a bending magnet, a wiggler of finite length, and an infinitely long wiggler. All our formulas are benchmarked agains numerical simulations with the CSRZ computer code

Formulae of luminosity and beam-beam tune shifts for flat-beam asymmetric colliders

This note outline the formulae of luminosity and beam-beam tune shifts applicable to flat-beam asymmetric colliders. The formulae are tested with the machine parameters of SuperKEKB.Comment: 18 pages, 3 figure

Generalized Panofsky-Wenzel theorem in curvilinear coordinate systems applicable to non-ultrarelativistic beams

This note gives an introduction to the theories of impedances and wakes in particle accelerators. The standard formulation assumes that the beam is traveling along a straight orbit with constant velocity $\vec{v}=v\vec{e}_z$. On this note, we show the possibility of extending the formulation for beams traveling along a curved orbit but assuming $|\vec{v}|=v$ to be constant.Comment: 22 pages, 1 figure. arXiv admin note: text overlap with arXiv:2101.0436

General formulation of impedance in Frenet-Serret coordinate system

In accelerator physics, the concept of impedance is popularly used to describe the interactions of charged particles inside a bunch or between bunches in a train. Standard formulations of impedance assume that the driving charge has a constant velocity $\vec{v}=v\vec{i}_z$ in the $z$ direction of the Cartesian coordinate system. For the case of driving charge moving along a curved orbit, impedance can be formulated in the Frenet-Serret coordinate system, but there seems to be a lack of systematic formulations. This note presents an effort in this direction.Comment: 11 page

Theories for correlating impedance computations with beam-based measurements in electron storage rings

As a stationary solution of the Vlasov-Fokker-Planck equation, the Haissinski equation predicts the equilibrium line density of a bunch circulating in a storage ring for a given wake function. Here, we show that, from the Haissinski equation, a few principles can be derived in a sef-consistent way and provide assistance in connecting impedance computations to beam-based measurements at electron storage rings.Comment: 5 pages, 6 figure

Potential-well bunch lengthening in electron storage rings

The cubic equation derived by B. Zotter has been popularly used for electron storage rings to describe the scaling law of potential-well bunch lengthening. This equation has also often been used to calculate the effective impedance when the bunch lengthening is measured or simulated. This paper discusses the validity of Zotter's equation and presents an alternative but self-consistent equation for potential-well bunch lengthening. Its applications to predicting bunch lengthening and extracting effective impedance from bunch length measurements are also addressed.Comment: 6 pages, 4 figures, submitted to 20th Annual Meeting of Particle Accelerator Society of Japan (PASJ2023). arXiv admin note: text overlap with arXiv:2307.0128

Singlino-dominated dark matter in general NMSSM

The general Next-to-Minimal Supersymmetric Standard Model (NMSSM) describes the singlino-dominated dark-matter (DM) property by four independent parameters: singlet-doublet Higgs coupling coefficient $\lambda$, Higgsino mass $\mu_{tot}$, DM mass $m_{\tilde{\chi}_1^0}$, and singlet Higgs self-coupling coefficient $\kappa$. The first three parameters strongly influence the DM-nucleon scattering rate, while $\kappa$ usually affects the scattering only slightly. This characteristic implies that singlet-dominated particles may form a secluded DM sector. Under such a theoretical structure, the DM achieves the correct abundance by annihilating into a pair of singlet-dominated Higgs bosons by adjusting $\kappa$'s value. Its scattering with nucleons is suppressed when $\lambda v/\mu_{tot}$ is small. This speculation is verified by sophisticated scanning of the theory's parameter space with various experiment constraints considered. In addition, the Bayesian evidence of the general NMSSM and that of $Z_3$-NMSSM is computed. It is found that, at the cost of introducing one additional parameter, the former is approximately $3.3 \times 10^3$ times the latter. This result corresponds to Jeffrey's scale of 8.05 and implies that the considered experiments strongly prefer the general NMSSM to the $Z_3$-NMSSM.Comment: 29 pages, 9 figure

Impacts of Intensified Agriculture Developments on Marsh Wetlands

A spatiotemporal analysis on the changes in the marsh landscape in the Honghe National Nature Reserve, a Ramsar reserve, and the surrounding farms in the core area of the Sanjiang Plain during the past 30 years was conducted by integrating field survey work with remote sensing techniques. The results indicated that intensified agricultural development had transformed a unique natural marsh landscape into an agricultural landscape during the past 30 years. Ninety percent of the natural marsh wetlands have been lost, and the areas of the other natural landscapes have decreased very rapidly. Most dry farmland had been replaced by paddy fields during the progressive change of the natural landscape to a farm landscape. Attempts of current Chinese institutions in preserving natural wetlands have achieved limited success. Few marsh wetlands have remained healthy, even after the establishment of the nature reserve. Their ecological qualities have been declining in response to the increasing threats to the remaining wetland habitats. Irrigation projects play a key role in such threats. Therefore, the sustainability of the natural wetland ecosystems is being threatened by increased regional agricultural development which reduced the number of wetland ecotypes and damaged the ecological quality

Gossip Consensus Algorithm Based on Time-Varying Influence Factors and Weakly Connected Graph for Opinion Evolution in Social Networks

We provide a new gossip algorithm to investigate the problem of opinion consensus with the time-varying influence factors and weakly connected graph among multiple agents. What is more, we discuss not only the effect of the time-varying factors and the randomized topological structure but also the spread of misinformation and communication constrains described by probabilistic quantized communication in the social network. Under the underlying weakly connected graph, we first denote that all opinion states converge to a stochastic consensus almost surely; that is, our algorithm indeed achieves the consensus with probability one. Furthermore, our results show that the mean of all the opinion states converges to the average of the initial states when time-varying influence factors satisfy some conditions. Finally, we give a result about the square mean error between the dynamic opinion states and the benchmark without quantized communication