title: Observation of synchrotron radiation from electrons accelerated in a petawatt-laser-generated plasma cavity.
abstract: The dynamics of plasma electrons in the focus of a petawatt laser beam are studied via measurements of their x-ray synchrotron radiation. With increasing laser intensity, a forward directed beam of x rays extending to 50 keV is observed. The measured x rays are well described in the synchrotron asymptotic limit of electrons oscillating in a plasma channel. The critical energy of the measured synchrotron spectrum is found to scale as the Maxwellian temperature of the simultaneously measured electron spectra. At low laser intensity transverse oscillations are negligible as the electrons are predominantly accelerated axially by the laser generated wakefield. At high laser intensity, electrons are directly accelerated by the laser and enter a highly radiative regime with up to 5% of their energy converted into x rays.
authors: The Blackett Laboratory, Imperial College London SW7 2AZ, United Kingdom.
authors: S
authors: S
authors: Kneip
authors: S R
authors: SR
authors: Nagel
authors: C
authors: C
authors: Bellei
authors: N
authors: N
authors: Bourgeois
authors: A E
authors: AE
authors: Dangor
authors: A
authors: A
authors: Gopal
authors: R
authors: R
authors: Heathcote
authors: S P D
authors: SP
authors: Mangles
authors: J R
authors: JR
authors: Marquès
authors: A
authors: A
authors: Maksimchuk
authors: P M
authors: PM
authors: Nilson
authors: K Ta
authors: KT
authors: Phuoc
authors: S
authors: S
authors: Reed
authors: M
authors: M
authors: Tzoufras
authors: F S
authors: FS
authors: Tsung
authors: L
authors: L
authors: Willingale
authors: W B
authors: WB
authors: Mori
authors: A
authors: A
authors: Rousse
authors: K
authors: K
authors: Krushelnick
authors: Z
authors: Z
authors: Najmudin