The Research On Readout Method For The Signals Of PandaX-Ⅲ TPC Detector

As the direction of partical physics research hot spot, neutrinoless double beta decay has vital significance to research for the properties of neutrino. At present there are many experiments about neutrinoless double beta decay in the world. For example, CUORE and GERDA located in the Underground laboratory of Gran Sasso national underground laboratory in Italy; EXO-200 is in WIPP; The NEXT located in the Canfranc; KamLAND-Zen located in the Kamiola. Last year, PandaX(Particle and Astrophysical Xenon Detector)-III started to look for neutrinoless double beta decay, which located in the underground laboratory in Jinpin mountain of Sichuan province of China.PandaX-III’s detector is high-pressure xenon gas (HPXe) time projection chamber(TPC). The event moves to the end cover readout detector Micromegas because of the action of drift electric field, which is readout by the Micromegas with message of time, location, charge. By computing the massage we can not only know the event energy accurately, but also rebuild the track of event in 3D.Because of the high pressure and long track of event in TPC, when there is include angle between track and end cover, the width of output signal will be huge. The width varies between 100ns to 300us. It is a big challenge for electronics design.This paper dig deeply in the signal readout method based on the electronics readout program made by PandaX-Ⅲ. This paper did the study of how noise, the width of signal, and sampling rate influence the signal readout method by simulating and testing in circuit separately.In this paper, there is a method to measure signal energy by measuring waveform area and peak simultaneously which is based on the signal characteristics of PandaX-III experiment. It assess the effect of noise and low sample rate to signal readout method.In this paper, based on the the characteristics of the waveform is low, a new way which provides trigger by area integral is proposed. This way solved tow problems by providing trigger with compering voltage. One is providing trigger by compering voltage may lost some event. The other is noise may make wrong trigger when waveform is low.