IOP PUBLISHING JOURNAL OF PHYSICS D: APPLIED PHYSICS J. Phys. D: Appl. Phys. 46 (2013) 245501 (8pp) doi:10.1088/0022-3727/46/24/245501 Electron radiography using a table-top laser-cluster plasma accelerator G C Bussolino 1 , A Faenov 2,3 , A Giulietti 1 , D Giulietti 1,4 , P Koester 1 , L Labate 1,4 , T Levato 1,5,6 , T Pikuz 2,3 and L A Gizzi 1,4 1 ILIL, Istituto Nazionale di Ottica, CNR, Via G. Moruzzi 1, Pisa, Italy 2 Joint Institute for High Temperatures, Russian Academy of Science (RAS), 13-2, Izhorskaya st., Moscow 125412, Russia 3 Quantum Beam Technology Directorate, Japan Atomic Energy Agency, 8-1-7 Umemidai, Kizugawa, Kyoto 619-0215, Japan 4 INFN Sezione di Pisa, Largo Pontecorvo 3, 56127 Pisa, Italy 5 Universit` a di Roma ‘Tor Vergata’, Dipartimento Ingegneria Industriale, Via del Politecnico 1, 00133 Roma, Italy 6 Fyzik´ aln´ ı´ ustav AV ˇ CR v.v.i., Na Slovance 2, 182 21 Praha 8, Czech Republic E-mail: giancarlo.bussolino@ino.it Received 21 December 2012, in final form 22 April 2013 Published 31 May 2013 Online at stacks.iop.org/JPhysD/46/245501 Abstract We explore the use of a laser-based electron gun for applications in transmission electron radiography and microscopy at electron energies up to 2MeV. This new approach holds the promise to overcome some limitations of existing conventional electron guns at high beam energies especially for ultrafast applications. Our laser-electron gun is based on titanium-sapphire, ultrashort pulse lasers to drive electron acceleration in a plasma. The focused laser pulse travels in a tailored Ar gas target and accelerates electrons to MeV energy in less than a millimetre. As a first application, we use this electron beam to perform contact transmission electron radiography of cm-scale thin and thick samples. We obtain transmission electron radiography of organic and inorganic dense objects over a field of view more than 50 mm wide. The images are well exposed and show details of both thick and thin samples. The spatial resolution for the current geometrical configuration was found to be approximately 60 µm and was limited by geometrical effects combined with the intrinsic detector resolution and diffusion in the sample. (Some figures may appear in colour only in the online journal) 1. Introduction Progress of medical and biological imaging using radiation and particle beams relies on the continuous innovation of both detection techniques and beam generators. Nowadays, in addition to ‘conventional’ transmission radiography and microscopy (which basically employ electrons up to a few hundreds of keV energy accelerated by electrostatic fields), advanced applications, such as ultrafast electron diffraction and microscopy, based on radio frequency (RF) driven linear accelerators, are actively studied. An alternative electron acceleration technique based on the original concept of laser-plasma acceleration [1] exploits the latest generation of high-power lasers in place of standard RF techniques and is found to be a thousand times more effective than conventional electron accelerators [2] leading to very compact and efficient electron beam generators. Laser pulses are focused on small gas targets to produce a plasma and accelerate electrons to MeV energy in a few millimetres. Laser-plasma acceleration has seen a dramatic development in recent years [3–5] with many laboratories involved worldwide [6] and is now sufficiently mature to be considered for applications. In the configuration investigated in detail in previous experiments at the Intense Laser Irradiation Laboratory (ILIL) at the National Institute of Optics (CNR-INO) in Pisa and described elsewhere [7, 8], the electron beam has physical and geometrical properties, which appear to be suitable for imaging 0022-3727/13/245501+08$33.00 1 © 2013 IOP Publishing Ltd Printed in the UK & the USA