Analysis of laser wakefield acceleration using ATF CO2 laser

In projections of laser wakefield acceleration (LWFA), long laser wavelength presents major advantages. A new opportunity for exploiting this promise is offered by a forthcoming upgrade at the Brookhaven National Laboratory (BNL) Accelerator Test Facility (ATF). The CO2 laser is being upgraded to deliver >1 TW peak power with similar to2-ps laser pulse length. With this upgrade, promising LWFA experiments at 10.6 mum will be possible. These experiments will also exploit the availability of equipment for generating plasmas by capillary-discharges at the ATF. This will enable acceleration over extended lengths without invoking self-focusing. Analytical modeling and numerical simulations are presented to evaluate the potential for such experiments with a long-wavelength laser. A major issue in LWFA is wake controllability and regularity, and the achievement of small energy spread. Here, the insights gained from controlled staging experiments during the STELLA program at the ATF will prove valuable. A possible embodiment for achieving this is the stimulated LWFA concept introduced here.