New batch system for 14C accelerator mass spectrometry (AMS). graphite targets preparation at the INGEIS laboratories, Argentina.

CORDERO OTERO, R R; PANARELLO, H.0.; TOMASINI, E.

Pucón

Congreso; III South American Sympusium on Isotope Geology; 2001

Universidad de Santiago

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0mm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US; mso-fareast-language:EN-US;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 30.0mm 70.85pt 30.0mm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> At present a new batch system for the production of graphite from CO2 is functioning at the INGEIS-14C laboratory. The main goal of the system is to do specific targets by catalytic reduction for a new AMS system which is being installed in the building of the Autoridad Regulatoria Nuclear. There are two methods for determining very low concentrations of radio nuclides: measuring the radiation emitted by their radioactive decay or measuring the particular atoms themselves. In one mg of carbon there are 5 x 1019 stable 12C atoms. Since the global atmospheric ratio 14C/12C = is ca 1,2 x 10-12, it contains 6 x 107 atoms of 14C and only one of these atoms decays in one hour. Conversely, this one mg used up in the ion source of an AMS can collect 6 x 105 14C atoms. This examples clearly shows the enormous gain in detection efficiency of atom collection of AMS over decay measurig techniques.  The main field of application of this line will be the radiocarbon dating and environmental studies, usingmaterials like hair, microfossils, atmopheric CO2, foraminifera, pictures and all that materials containing small quantities of carbon that make impossible their dating by traditional β-counting.