本論文中我們研究透過正向碰撞的電漿噴流產生的電漿盤，電漿盤可以用來模擬銀河系、恆星形成區和赫比格-哈羅等大尺度且難以研究的天文物理天體。實驗的進行是使用具有量測裝置的 1-kJ 脈衝功率系統。1-kJ 脈衝電源系統由 20 個電容組成，總電容值為 5 µF，電容充電電壓為 20 kV。當系統放電時，產生的脈衝電流峰值約 135 kA ，上升時間約 1592 ns。我們使用此脈衝電流來驅動由一對正面相接的錐形導線陣列所組成的雙錐形導線陣列。雙錐形導線陣列使用 20 µm 的鎢絲架設，與中心軸有 30° 的傾角。 當電流通過鎢絲時，電漿從鎢絲上燒蝕出來，並且透過不均勻的軸向壓縮形成電漿噴流。最後，從正面相接的兩個錐形導線陣列所產生的兩個對向移動的電漿噴流互相碰撞產生電漿盤。為了拍攝影像並獲得電漿噴流與電漿盤的特徵，我們建立了拍攝時間解析的雷射相機系統，以及拍攝時間積分的可見光相機系統，並運用射流速度量測系統獲得電漿噴流的速度。然而，在時間積分與時間解析的影像中，我們觀察到原始的雙錐形導線陣列存在不對稱的問題。因此，我們設計了不同版本的雙錐形導線陣列來解決不對稱的問題。經過多次的測試，運用黃銅圓盤作為頂板、原版的底部線盤和塑料的中層支架作為雙錐形導線陣列，有效的形成了兩個對向的電漿噴流。最後，我們觀察到兩個電漿噴流對撞之後，在雙錐形導線陣列的中間平面上方約0.15 mm 處，產生了長度為 0.68 mm、寬度為 7.15 mm 的電漿盤。

In the thesis, we were studying the plasma disk generated from two head-on plasma jets colliding with each other. The plasma disk can be used to simulate astrophysical objects such as Milky Way, Star-forming regions, and Herbig-Haro(HH) objects which are large-scale and difficult to study. We used the 1-kJ pulsed-power system with a suite of diagnostics for experiments. The 1-kJ pulsed-power system consists of 20 capacitors with a total capacitance of 5 µF and is charged to 20 kV. When the system discharges, it generates a pulsed current of ∼135 kA with a rise time of ∼1592 ns. The pulsed current is used to drive the bi-conical-wire array consisting of a pair of head-on conical-wire arrays. The tungsten wires with a diameter of 20 µm used in the bi-conical-wire array have a 30° inclination angle with respect to the axis. When the current passes through the tungsten wires, the coronal plasma ablated from the wires and compressed by the nonuniform z-pinch effect to form the plasma jet. Then, two plasma jets generated by the bi-conical-wire array collide with each other and form the plasma disk. In order to capture the image and obtain the characterization of the plasma jet/disk, we built the laser-camera system for taking time-resolved images from the side, the visible-light camera system for taking time-integrated images from the side and the top, and the jet-velocity measurement system for obtaining the speed of plasma jet. However, the original bi-conicalwire array had the asymmetric issue observed in both time-integrated and time-resolved images. Therefore, we designed different versions of bi-conical-wire arrays to solve the problem. After several tests, the brass disk as the top plate, the original bottom wire support as the bottom plate, and plastic middle holders for the bi-conical-wire array are effectively accumulated plasma for forming two head-on plasma jets. Finally, the plasma disk with a height of ∼0.68 mm and a width ∼7.51 mm was generated ∼0.15 mm above the middle plane of the bi-conical-wire array when two plasma jets collided with each other.

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