The cross section of nuclear reaction and the isomeric yield ratio in the reaction products are of great significance in the fields of nuclear structure, nuclear reaction mechanism and nuclear astrophysics. At the 200 TW laser facility of CLAPA Laboratory, bremsstrahlung radiation with peak intensity of 10^19-20/s, cut-off energy of tens to hundreds of MeV and pulse width of tens of ps can be stably obtained using the laser wakefield electrons, which is suitable for the measurement of the average cross section and isomer ratio of photonuclear reactions. The photonuclear activation of various targets, such as Au, In, Zn, Cr, Al are experimentally performed using the laser-driven gamma source. The flux averaged photonuclear cross sections and the isomeric ratios were obtained. The sensitivity of isomeric ratios to optical potential, nuclear level density function and gamma strength function are investigated. The results show that the related measurement results can constrain the typical nuclear structure parameters.

Photonuclear reactions,laser wakefield acceleration,nuclear isomer