Proton radiography of magnetic fields generated with an open-ended coil driven by high power laser pulses

• Published in: Matter and radiation at extremes Vol. 1; no. 4; pp. 187 - 191
• Main Authors: Liao, Guoqian, Li, Yutong, Zhu, Baojun, Li, Yanfei, Li, Fang, Li, Mengchao, Wang, Xuan, Zhang, Zhe, He, Shukai, Wang, Weiwu, Lu, Feng, Zhang, Faqiang, Yang, Lei, Zhou, Kainan, Xie, Na, Hong, Wei, Gu, Yuqiu, Zhao, Zongqing, Zhang, Baohan, Zhang, Jie
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.2016; AIP Publishing LLC
• Subjects: Laser-driven coil targets; Proton radiography; Strong magnetic field; 52.70.Ds; 52.38.Fz; Strong magnetic field; 52.50.Jm; Proton radiography; Laser-driven coil targets
• ISSN: 2468-080X; 2468-2047; 2468-080X
• DOI: 10.1016/j.mre.2016.06.003

Recently generation of strong magnetic (B) fields has been demonstrated in capacitor coils heated by high power laser pulses [S. Fujioka et al., Sci. Rep. 3, 1170 (2013)]. This paper will present a direct measurement of B field generated with an open-ended coil target driven by a nanosecond laser pulse using ultrafast proton radiography. The radiographs are analyzed with particle-tracing simulations. The B field at the coil center is inferred to be ∼50 T at an irradiance of ∼5 × 1014 W·cm−2. The B field generation is attributed to the background cold electron flow pointing to the laser focal spot, where a target potential is induced due to the escape of energetic electrons.