Ultrafast X-Ray Detector and its Gain Uniformity

Houzhi Cai,Jinyuan Liu,Wenyong Fu,Pokun Deng,Dong Wang

doi:10.1109/access.2019.2950556

Houzhi Cai, Jinyuan Liu + Show 3 more

Open Access

https://doi.org/10.1109/access.2019.2950556

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Abstract

An ultrafast x-ray detector consisted of an electron pulse time-dilation device, a combined electromagnetic lens system, a microchannel plate (MCP) gated imager, and an electrical pulse generator is reported. The time-dilation device is used to magnify the temporal width of the electron beam created from the photo-cathode (PC), and then the combined electromagnetic lens system images the dilated electron beam onto the MCP. Finally, the MCP imager samples the dilated electron signal and outputs corresponding visible light. A measured temporal resolution of 80 ps for the detector is achieved while the electron pulse is not dilated. The resolution is improved to 12 ps while an excitation pulse with 3.1 V/ps rising edge gradient is used to drive the PC to dilate the electron pulse. Moreover, the gain uniformity of the detector is also tested, which shows the gain is decreased gradually with the excitation pulse propagating on the PC and the drop in gain is about $1.7\times $ .

Highlights

X-ray imagers based on the gated microchannel plate (MCP) are two dimensional ultrafast detectors, and have been used in the inertial confinement fusion (ICF) or fast Z-pinch experiments successfully [1]–[8]
An ultrafast x-ray imager with name of DIXI has been developed [13]–[15]. It uses an electron pulse-dilation to improve the temporal resolution to be better than 10 ps
An ultrafast x-ray detector using electron pulse-dilation is presented, and the temporal resolution as well as the gain uniformity are provided in this paper

Summary

INTRODUCTION

X-ray imagers based on the gated microchannel plate (MCP) are two dimensional ultrafast detectors, and have been used in the inertial confinement fusion (ICF) or fast Z-pinch experiments successfully [1]–[8]. An ultrafast x-ray imager with name of DIXI has been developed [13]–[15] It uses an electron pulse-dilation to improve the temporal resolution to be better than 10 ps. An ultrafast x-ray detector using electron pulse-dilation is presented, and the temporal resolution as well as the gain uniformity are provided in this paper. The PC was driven by a negative pulse with 350 ps rising edge in the previous camera to obtain the electron time-dilation. In the ICF experiment with about 1-2 ns duration, the rising edge with 1.4 ns is better than that of 350 ps

DETECTOR ARCHITECTURE

GAIN UNIFORMITY MEASUREMENT