Status of the geochemical determination of the solar pp-neutrino flux by LOREX

Pavicevic, Milorad and Amthauer, Georg and Anicin, Ivan and Boev, Blazo and Bosch, Fritz and Bruchle, Willy and Djurcic, Z. and Faestermann, Thomas and Henning, Walter and Jelenkovic, Rade and Niedermann, Samuel and Pejovic, Vladan and Vermeesch, P. and Weiss, Achim (2012) Status of the geochemical determination of the solar pp-neutrino flux by LOREX. In: XXIV International Conference on Neutrino Physics and Astrophysics, 3 – 9 June 2012, Kyoto, Japan.

[img]
Preview
Text
Abstract_LOREX_Neutrino2012 - 15 04 2012.pdf

Download (97Kb) | Preview

Abstract

LOREX, the acronym for LORandite EXperiment, is the only geochemical solar neutrino experiment still actively pursued. It addresses the determination of the long-time average of the solar neutrino flux with the thallium-bearing mineral lorandite, TlAsS2, from the mine of Allchar, FYR Macedonia, via the neutrino-capture reaction 205Tl + ν(e) → 205Pb + e-. The final step of LOREX would be the extraction of lorandite and the quantitative determination of the ratio of 205Pb / 205Tl atoms, thus providing the product of solar neutrino flux and neutrino-capture cross section, integrated over the age of lorandite of 4.31 ∙ 10^6 yr. Moreover, the detector offers the lowest threshold among all the detectors of only 52 keV for solar ppneutrinos. This paper presents new data on accurate geological age of the minerals at Allchar, as well as the recent results for erosion rates at two lorandite rich locations. These are based on Accelerator Mass Spectrometry (AMS) determination of 10Be, 26Al and 53Mn in characteristic samples and on the independent geomorphological investigations. Reliable erosion rates are of paramount importance for the proper determination of background of 205Pb induced by cosmic-ray muons. Provided that these satisfactorily high values of erosion rates are corroborated by more measurements of additional probes, the experiment is expected to reach an acceptable signal-to-background ratio. Finally, it is discussed how to obtain the still unknown capture probability of solar pp-neutrinos from 205Tl into 205Pb via the measurement of the lifetime for the bound beta decay of the completely ionised 205Tl, as well as how to count by Schottky mass spectrometry the extremely small number of 205Pb atoms found within the few kilograms of the mineral, needed to attain the accuracy of the final result of the order of some 30%. Both crucial measurements are planned to be carried out at the GSI.

Item Type: Conference or Workshop Item (Paper)
Subjects: Natural sciences > Other natural sciences
Divisions: Faculty of Natural and Technical Sciences
Depositing User: Blazo Boev
Date Deposited: 28 May 2013 10:48
Last Modified: 17 Mar 2015 14:37
URI: http://eprints.ugd.edu.mk/id/eprint/6428

Actions (login required)

View Item View Item