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We report on new findings in a laser driven enhanced electron beam generationin the multi MeV energy range at moderate relativistic laser intensities andtheir applications. In our experiment, an intense sub-picosecond laser pulsepropagates through a plasma of a near critical electron density (NCD) anddirect laser acceleration (DLA) of electrons takes place. The breakthroughtoward high current relativistic electron beams became possible due toapplication of low density polymer foams of sub-mm thickness. In foams, theNCD-plasma was produced by a mechanism of super-sonic ionization. Compared toNCD-plasmas generated by laser irradiation of conventional foils, the DLAacceleration path in foams was strongly enhanced. Measurements resulted into11{\div}13 MeV of the effective electron temperature and up to 100 MeV maximumof the electron energy measured in the laser pulse propagation direction. Thegrowth of the electron energy was accompanied by a strong increase of thenumber of super-ponderomotive electrons and a well-defined directionality ofthe electron beam that propagates in a divergence cone with a half angle of12{\deg}. For the energy range above 7.5 MeV that is relevant for gamma-drivennuclear reactions, we estimate a charge carried by these well-directed electronbeams as high as 50 nC and a corresponding efficiency of the laser energyconversion into electrons of 6%. The electron spectra generated by theDLA-mechanism in NCD-plasma at 1019 Wcm-2 laser intensity were compared withthose measured in shots onto conventional metallic foils at ultra-relativisticlaser intensities of 1021 Wcm-2 . In the last case, the twice lower effectiveelectron temperature and the twice lower maximum of the electron energy wereregistered. The substantial difference in the electron spectra for these twocases presented itself in the isotope production yield.

High current well-directed beams of super-ponderomotive electrons for laser driven nuclear physics applications