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arXiv · 2001.02590

Signature of Collective Plasma Effects in Beam-Driven QED Cascades

Kenan Qu·Sebastian Meuren·Nathaniel J. Fisch
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Abstract

QED cascades play an important role in extreme astrophysical environments like magnetars. They can also be produced by passing a relativistic electron beam through an intense laser field. Signatures of collective pair plasma effects in these QED cascades are shown to appear, in exquisite detail, through plasma-induced frequency upshifts in the laser spectrum. Remarkably, these signatures can be detected even in small plasma volumes moving at relativistic speeds. Strong-field quantum and collective pair plasma effects can thus be explored with existing technology, provided that ultra-dense electron beams are colocated with multi-PW lasers.

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Kenan Qu, Sebastian Meuren, Nathaniel J. Fisch. 2021-09-20. Signature of Collective Plasma Effects in Beam-Driven QED Cascades. https://doi.org/10.1103/physrevlett.127.095001

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