Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

作     者：J.Cikhardt M.Gyrdymov S.Zähter P.Tavana M.M.Günther N.Bukharskii N.Borisenko J.Jacoby X.F.Shen A.Pukhov N.E.Andreev O.N.Rosmej J.Cikhardt;M.Gyrdymov;S.Zähter;P.Tavana;M.M.Günther;N.Bukharskii;N.Borisenko;J.Jacoby;X.F.Shen;A.Pukhov;N.E.Andreev;O.N.Rosmej

作者机构：Faculty of Electrical EngineeringCzech Technical University in Prague16627 Prague 6Czech Republic Goethe UniversityFrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbHPlanckstraße 164291 DarmstadtGermany Focused Energy GmbHIm Tiefen See 4564293 DarmstadtGermany National Research Nuclear University MEPhIKashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RASLeninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University DüsseldorfUniversitätsstrasse 1DüsseldorfGermany Joint Institute for High TemperaturesRASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation Moscow Institute of Physics and TechnologyInstitutskiy Pereulok 9141700 DolgoprudnyRussia 

出 版 物：《Matter and Radiation at Extremes》 (极端条件下的物质与辐射（英文）)

年 卷 期：2024年第9卷第2期

页      面：26-35页

核心收录：

学科分类：080901[工学-物理电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 08[工学] 080401[工学-精密仪器及机械] 0804[工学-仪器科学与技术] 070204[理学-等离子体物理] 0803[工学-光学工程] 0702[理学-物理学] 

基　　金：supported by the Czech Ministry of Education,Youth and Sports(Project No.CZ.02.2.69/0.0/0.0/18_053/0016980) the Grant Agency of the Czech Republic(Grant No.GM23-05027M) 

主　　题：laser acceleration critical 

摘      要：Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 MeV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies 5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHM of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.