APPLICATIONS OF ACCELERATOR MASS SPECTROMETRY TO GEOLOGY, NUCLEAR SAFEGUARDS AND ASTROPHYSICS

ANDRES ARAZI; DANIEL ABRIOLA; OSCAR CAPURRO; MARIA ANGÉLICA CARDONA; EZEQUIEL DE BARBARÁ; JORGE FERNANDEZ NIELLO; JORGE GALLARDO; FERNANDO GOLLAN; DANIEL HOJMAN; GUILLERMO MARTI; AGUSTIN NEGRI; ALBERTO PACHECO; DARIO PABLO RODRIGUES FERREIRA MALTEZ; NICOLAS SAMSOLO; G. KORSCHINEK; SILKE MERCHEL; GEORG RUGEL; PETER STEIER

Mangarativa

Congreso; Reuniâo de Trabalho sobre Física Nuclear no Brasil; 2015

The Accelerator Mass Spectrometry (AMS) technique profits from the breakup of molecules and the high energy of tandem accelerators to achieve the best sensitivity for the detection of long-lived radioisotopes. Being capable of detecting one radioactive atom among 1015 of its stable isotope in samples smaller than 1 mg, the AMS technique has been successfully applied in a wide range of areas such as archeology (14 C), geology (10Be, 26Al), hydrology (36Cl), nuclear safety and radioactive pollution control (129 I), astrophysics (53Mn,60Fe), andnuclear safeguard (236 U).In this presentation we will report three ongoing applications of this technique to different research areas:a) Geological studies of the thrust fault in marine sediments through measurements of the depth profile of cosmogenic 10 Be (T1/2 = 1,39 Ma) in the region where the Nazca tectonic plate subducts bellow the SouthAmerican one; b) Measurements with a time-of-flight system at the TANDAR Accelerator of the enrichment level (235 U/U ratio) of uranium samples of few nanograms for safeguard applications; c) Measurements of theElab = 197 keV resonance strength of the 25Mg(p,γ)26 Alg reaction, which is responsible for the formation of interstellar 26 Al in novae explosions. In this last case, 25Mg targets are proton bombarded, chemically treated and then the formed 26 Al (T1/2 = 0,72 Ma) is off-line counted.