无中微子双贝塔衰变实验高密度电荷收集节点自组织读出网络研究

The Topmetal series charge sensor developed by Central China Normal University has excellent low noise performance. And a single electrode sensor Topmetal-S is being developed and optimized specifically for the neutrinoless double beta decay experiment. High pressure gas time projection chamber (TPC) made of Topmetal-S charge plane can achieve high energy resolution and high spatial resolution on the premise of stability, uniformity and scalability. This requires tile about one hundred thousand sensors on a meter-sized plane, the biggest challenge is the readout of the high density data channel. The purpose of this project is to use the self-organizing network to realize the high density charge collection node readout: as the node of the network, the sensor is connected with the local neighbor nodes. Nodes not only generate and transmit their own data, but also responsible for forwarding data transmitted by other nodes. The data is transmitted to the plane edge in the form of packets, and then output to the outside of the TPC, hence the signals that need to draw out from the plane are greatly reduced, also easy to achieve high pressure air tightness of the TPC; A distributed routing algorithm based on local information is used in the readout circuit, which can be integrated into the sensor, thus it will not introduce additional radioactive material to TPC; In addition, with the increase of the scale the local performance of each node does not decay, and the total bandwidth increases, which has the characteristics of high efficiency, low cost and scalability.

华中师范大学研制的Topmetal系列电荷传感器芯片具有优异的低噪声性能，并且针对无中微子双贝塔衰变实验设计了单电极传感器Topmetal-S，利用其组成的电荷收集平面制成的高压气体时间投影室（TPC）在保证稳定性、均匀性和可扩展性的前提下能达到高能量分辨率和高空间分辨率。这需要在米大小的平面上平铺约十万个传感器，最大的挑战是高密度数据通道读出。本项目旨在利用自组织网络实现高密度电荷收集节点的读出：传感器作为读出网络的节点，主要与本地相邻节点互连，节点不仅产生和传输本身数据，还负责转发其他节点传输来的数据，数据以包的形式向平面边缘传输，再输出到TPC外部，极大减少了引出信号的数量，也易于实现TPC高压气密性；读出电路采用分布式路由算法，仅依赖本地信息，可集成到芯片中，不会给TPC引入额外的放射性材料；当规模扩大后节点的本地性能不会衰减，且总带宽增大，具有效率高、开销低、可扩展性好等特点。