Applications of accelerator mass spectrometry to geology, nuclear safeguards and astrophysics,

A. ARAZI; D. ABRIOLA; O. CAPURRO; M.A. CARDONA; E. DE BARBARÁ; J. FERNÁNDEZ NIELLO; J. GARCÍA GALLARDO; F. GOLLAN; D. HOJMAN; G. MARTÍ; A. NEGRI; A. PACHECO; D. RODRIGUES; N. SAMSOLO; G. KORSCHINEK; S. MERCHEL; G. RUGEL; P. STEIER

Mangaratiba

Workshop; XXXVIII Reunião de Trabalho sobre Física Nuclear no Brasil; 2015

Sociedade Brasileira de Fisica

The Accelerator Mass Spectrometry (AMS) technique profits from the breakup of molecules and the highenergy of tandem accelerators to achieve the best sensitivity for the detection of long-lived radioisotopes. Beingcapable of detecting one radioactive atom among 1015 of its stable isotope in samples smaller than 1 mg, theAMS technique has been successfully applied in a wide range of areas such as archeology (14C), geology (10Be,26Al), hydrology (36Cl), nuclear safety and radioactive pollution control (129I), astrophysics (53Mn,60Fe), andnuclear safeguard (236U).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 ofcosmogenic 10Be (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 enrichmentlevel (235U/U ratio) of uranium samples of few nanograms for safeguard applications; c) Measurements of theElab = 197 keV resonance strength of the 25Mg(p,γ)26Algreaction, which is responsible for the formation ofinterstellar 26Al in novae explosions. In this last case, 25Mg targets are proton bombarded, chemically treatedand then the formed 26Al (T1/2= 0,72 Ma) is off-line counted.