  Bremsstrahlung x-rays generated in laser-solid interactions can be used as
light sources for high-energy-density science. We present electron and x-ray
spectra from particle-in-cell and Monte Carlo simulations, varying laser pulse
intensity and duration at fixed energy of 200$\,$J. Superponderomotive electron
temperatures are observed at low intensity; a new temperature scaling is given
that depends on pulse duration and density scale length. Short, high-intensity
pulses create low-divergence electron beams before self-generated magnetic
fields evolve, resulting in more forward-going MeV x-rays.
