[en] A few high density UV-EPROM's (32Kb x 8) were irradiated with 5.41 MeV energy α-particles with fluences from 10⁴ to 10⁸ alphas/cm² and 100 MeV nickel, iodine and silver ions for low fluences between 5 x 10⁷ and 10⁸ ions/cm². The energy and ion species was selected on the basis of predicted threshold values of linear energy transfer (LET) in silicon. The program which was stored in the memory found to be changed from 0 to 1 and 1 to 0 state, respectively. On the basis of changed states, the cross-sections (σ) were calculated to investigate the single event effects/upsets. No upset was observed in case of α-particle since it has very low LET, but the SEU cross-section found to be more in case of Iodine i.e. 2.29 x 10^-3 cm² than that of nickel, 2.12 x 10^-3 cm² and silver, 2.26 x 10^-3. This mainly attributes that LET for iodine is more as compared to silver and nickel ions, which deposits large amount of energy near the sensitive node of memory cell in the form of electron-hole pairs required to change the state. These measured SEU cross-section were also compared with theoretically predicted values along with the Weibull distribution fit to the ion induced experimental SEU data. The theoretical predicted SEU cross-section 3.27 x 10^-3 cm² found to be in good agreement with the measured SEU cross-section