Caustic structures in x-ray Compton scattering off electrons driven by a short intense laser pulse. (17th February 2016)

• Record Type: Journal Article
• Authors: Seipt, D; Surzhykov, A; Fritzsche, S; Kämpfer, B
• Is Part Of: New journal of physics. Volume 18:Number 2(2016:Feb.)
• Publication Date: 2016-02-17
• Subjects: XFEL -- caustics -- intense laser pulses -- laser-assisted Compton scattering -- strong-field QED; 12.20.Ds -- 32.80.Wr -- 41.60.Cr; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/18/2/023044
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: We study the Compton scattering of x-rays off electrons that are driven by a relativistically intense short optical laser pulse. The frequency spectrum of the laser-assisted Compton radiation shows a broad plateau in the vicinity of the laser-free Compton line due to a nonlinear mixing between x-ray and laser photons. Special emphasis is placed on how the shape of the short assisting laser pulse affects the spectrum of the scattered x-rays. In particular, we observe sharp peak structures in the plateau region, whose number and locations are highly sensitive to the laser pulse shape. These structures are interpreted as spectral caustics by using a semiclassical analysis of the laser-assisted QED matrix element, relating the caustic peak locations to the laser-driven electron motion.