Multiparticle photonuclear reactions in 203Tl nuclei

The thallium isotopes ²⁰³Tl and ²⁰⁵Tl were irradiated using a beam of bremsstrahlung gamma quanta with the maximum energy E _γ ^m = 50 MeV from an RTM-70 electron racetrack microtron installed at the Scobeltsyn Nuclear Physics Research Institute (Lomonosov Moscow State University, Russia). The gamma spectra of the residual activity were measured for an irradiated sample. Photonuclear reactions in the ²⁰³Tl nuclei with emission from one to four neutrons were observed experimentally. The relative yields of the reactions ²⁰³Tl(γ,n)²⁰²Tl, ²⁰³Tl(γ,2n)²⁰¹Tl, ²⁰³Tl(γ,3n)²⁰⁰Tl, and ²⁰³Tl(γ,4n)¹⁹⁹Tl were determined for the first time.