極高能宇宙微中子誘發之近場契忍可夫輻射的新計算法

Abstract

利用無線電波段偵測宇宙極高能微中子已經漸漸成為一個成熟的領域。無線電訊號來自於高能粒子簇射產生的契忍可夫輻射。我們利用時域有限差分方法，發展了一套計算無線電訊號的程式，提供了直接且快速的方法來計算近場輻射。這對極高能粒子簇射產生的訊號是重要的，特別是對於微中子經由C.C.過程產生的輕子所引發之電磁簇射。

The radio approach for detecting the ultra-high energy cosmic neutrinos has become a mature field. The signals in radio detection are originated from the Cherenkov radiation of particle showers. We present a calculation method of Cherenkov pulses based on finite-difference time-domain (FDTD) method. Our method provides a straightforward way of calculating the near field radiation, which would be important for ultra high energy particle showers, especailly the electromagnetic showers induced by the high energy leptons produced in the neutrino charge current interactions.