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Gamma-ray large area space telescope (GLAST) is a next generation high-energy gamma-ray space observatory designed for observations of celestial gamma-ray sources in the energy band extending from 10 MeV to more than 100 GeV. The main instrument, the large area telescope (LAT), consists of a microstrip silicon tracker, a calorimeter, an anticoincidence detector, and the data acquisition (DAQ) system. This paper summarizes the results obtained during the radiation testing of the ASIC chips used in the LAT tracker. Both single event effects (SEE) and total ionizing dose effect (TID) tests have been performed, as part of the radiation hardness assurance (RHA) for the planned 5-yr mission. Heavy-ion SEE tests have been performed at the SIRAD irradiation facility at the INFN National Laboratories of Legnaro, Italy (LNL) and at the Texas A&M University (TAMU) Cyclotron Institute, with LET values ranging up to ∼80 MeV × cm²/mg. The tolerance of the chips to ionizing radiation has been evaluated with heavy ions and by irradiating chips with the spherical 60Co gamma source of the LNL CNR-ISOF laboratory. [ABSTRACT FROM AUTHOR]

Abstract: An axial ion electron emission microscope (IEEM) has been built at the SIRAD irradiation facility at the 15MV Tandem accelerator of INFN Legnaro National Laboratory (Padova, Italy) to obtain a micrometric sensitivity map to single event effects (SEE) of electronic devices. In this contribution we report on two experiments performed with the IEEM. Si3N4 ultra-thin membranes with a gold deposition were placed on the device under test (DUT) to ensure a uniform and abundant secondary electron emission In the first experiment we measured an IEEM ion detection efficiency of 83% with a 58Ni (220MeV) beam, in good agreement with the expected value. The second experiment allowed us to estimate the lateral resolution of the IEEM. The positions of ion induced single event upsets (SEU) in a synchronous dynamic random access memory (SDRAM), used as a reference target, were compared with the corresponding ion impact points reconstructed by the IEEM. The result (FWHM ∼4.4μm with a 79Br beam of 214MeV) is encouraging because of the residual presence of distortions of the image and mechanical vibrations. [Copyright &y& Elsevier]

Abstract: The Ion Electron Emission Microscope (IEEM) of the SIRAD irradiation facility at LNL (Legnaro, Italy) has been used to perform an Ion Beam Induced Charge Collection (IBICC) type experiment irradiating a power MOSFET device with 223MeV 79Br ions. The ion-induced drain current pulse signals at different bias conditions were correlated with the ion impacts reconstructed by the IEEM to disentangle, with micrometric resolution, regions of the device with different sensitivity to the impinging ions. [Copyright &y& Elsevier]