Fast electron heating of a solid target in ultrahigh-intensity laser pulse interaction.

We report one of the first measurements of induced heating due to the transport of a fast electron beamgenerated by an ultrashort pulse laser interaction with solid targets. Rear-side optical reflectivity and emissivityhave been used as diagnostics for the size and temperature of the heated zone. A narrow spot has been observedof the order of the laser focus size. Values up to ,10 eV at the target back surface were inferred from theexperimental data and compared with the predictions of a hybrid collisional-electromagnetic transportsimulation.DOI: 10.1103/PhysRevE.70.055402 PACS number(s): 52.50.Jm, 52.38.Kd, 52.57.Kk