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Sun, Xu

Publications and source records attributed to Sun, Xu.

Properties of the QCD matter: review of selected results from the relativistic heavy ion collider beam energy scan (RHIC BES) program

In the paper, we discuss the development of the multigap resistive plate chamber time-of-flight (TOF) technology and the production of the solenoidal tracker at RHIC (STAR) TOF detector in China at the beginning of the twenty-first century. Subsequently, recent experimental results from the first beam energy scan program (BES-I) at the Relativistic Heavy Ion Collider (RHIC) pertaining to measurements of collectivity, chirality, criticality, global polarization, strangeness, heavy flavor, dilepton and light nuclei productions are reviewed.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Efficient Reformulation and Optimization for SC-ACOPF with Line Switching

This project aims to develop efficient and robust computational methods for solving the security-constrained alternating current optimal power flow problem (SC-ACOPF). The SC-ACOPF problem is a central problem in operating the electric power grids in the United States. It determines the most economically efficient way to operate the generation and transmission system to meet daily electricity demand. The solution found by solving an SC-ACOPF problem must satisfy the physics of the alternating current (AC) power flows, various generator and network operational constraints, and must maintain secure operation under various contingency scenarios, where a generator, a transmission branch, or a transformer may unexpectedly trip offline.

97 MATHEMATICS AND COMPUTING↗

Distributed control of electric power grids

A method for determining power output levels of a plurality of nodes in an electric power system includes receiving, at a first node of the plurality of nodes, voltage information and multipliers of all neighboring nodes of the first node within the electric power system, determining, by the first node, a local power generation and a local voltage using the voltage information and the multipliers of the neighboring nodes and distributing the local power generation and the local voltage to the neighboring nodes, determining, by the first node, an estimated voltage of each of the neighboring nodes and distributing the estimated voltage to each of the neighboring nodes, and updating, by the first node, a local multiplier using the voltage information received from the neighboring nodes and the estimated voltage of each of the neighboring nodes determined by the node.

Ghosh, Soumyadip↗

Investigation of the Elliptic Flow Fluctuations of the Identified Particles Using the a Multi-Phase Transport Model

A Multi-Phase Transport (AMPT) model is used to study the elliptic flow fluctuations of identified particles using participant and spectator event planes. The elliptic flow measured using the first order spectator event plane is expected to give the elliptic flow relative to the true reaction plane which suppresses the flow fluctuations. However, the elliptic flow measured using the second-order participant plane is expected to capture the elliptic flow fluctuations. Our study shows that the first order spectator event plane could be used to study the elliptic flow fluctuations of the identified particles in the AMPT model. The elliptic flow fluctuations magnitude shows weak particle species dependence and transverse momentum dependence. Such observation will have important implications for understanding the source of the elliptic flow fluctuations.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗