Betatron Radiation Production from Laser Plasma Accelerator Silvia

Betatron Radiation Production from Laser Plasma Accelerator Silvia Cipiccia University of Strathclyde

Outline • • • LWFA Betatron radiation emission during LWFA ASTRA Gemini 2010: Experimental Results Betatron Experiment @ Strathclyde Conclusions Glasgow, 13 September 2010

LWFA When a relativistic laser pulse propagates through an underdense plasma, a plasma wave is generated. Electrons, surfing the wave, can be accelerated up to 100 Ge. V/m.

Betatron radiation emission during LWFA BUBBLE REGIME • Laser ponderomotive force creates stable evacuated spherical structures trailing the laser pulse • Trapped electrons undergo transverse oscillations while accelerating • Synchrotron like radiation is emitted in a narrow cone

Betatron radiation emission during LWFA SCALING LAWS Acceleration: • Bubble radius: • Dephasing Length: • Max Energy Gained: Betatron Radiation: • Betatron Frequency: • Transverse momentum: • Divergence: • Critical photon Energy: • Efficiency:

Betatron radiation emission during LWFA BETATRON RESONANCE • The bubble is partially filled by laser pulse • Electrons can enter into resonance with the laser field • Laser drives larger amplitude betatron oscillations: – rb, ab, Ec increase

ASTRA Gemini 2010: Experimental Results • Laser Energy: 4 - 10 J • Laser wavelength: 800 nm • Pulse length: 50 - 60 fs • capillary length: 4 cm • spot size: 35 mm • capillary diameter: 300 mm • Initial a 0: 2 • plasma density: 1 - 4 x 1018 cm-3

Betatron Experiment @ Strathclyde

Conclusions • Betatron radiation from plasma wiggler: – – Tuneable energy from tens of ke. V to Me. V Bright source: 1023 photons/s mrad 2 mm 2 0. 1% B. W Ultrashort pulse: ~10 fs pulse duration Spatially coherent: phase contrast imaging • Next step: – – Higher energies: a 0 = 10 -> Ec = 5 Me. V Use betatron radiation as tool to monitor e-beam dynamics Medical applications: radioisotope generation Imaging

Acknowledgment • Our group in Strathclyde – R. Islam, E. Brunetti, B. Ersfeld, A. Noble, R. Issac, G. Raj, T. Mc. Canny, D. Clark, G. Vieux, M. Wiggins, G. Welsh, M. P. Anania, S. Chen, J. Farmer, X. Yang, S. Abuazoum, R. Shanks, G. Manahan, C. Aniculaesei, D. Grant, A. Subiel, Y. Kravets, R. Burgess, D. Jaroszynski • Dr. Albert Reitsma • Glasgow University – D. Maneuski, V. O’Shea, R. Montgomery, G. Smith, D. Hamilton, M. Hoek, B. Seitz, • IST Lisbon – N. Lemos, J. M. Dias, L. Silva • CLF – R. Pattathil, D. Symes, P. Foster

THANK YOU