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DOE OSTI · 21410790

Nuclear Physics Underground

Bemmerer, Daniel
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Abstract

Precisely known nuclear cross sections are an essential ingredient for the modeling of nuclear processes in our Sun, in stars, and in the Big Bang. Uncertainties due to theoretical extrapolations can be avoided if experimental data are available directly at astrophysically relevant energies. Since such energies are typically far below the Coulomb barrier, this entails cross section measurements in the picobarn range.The Laboratory for Underground Nuclear Astrophysics (LUNA) inside the Gran Sasso mountain in Italy takes up this challenge by combining accelerator-based experiments with low-background measurement techniques. Using this approach, in recent years several reactions relevant to hydrogen burning have been studied, e.g. {sup 3}He({alpha},{gamma}){sup 7}Be and {sup 14}N(p,{gamma}){sup 15}O. The implications of the data range from an independent lower limit on the age of the universe to a precise solar thermometer.Based on this progress, currently there are efforts in several countries to construct new underground accelerators. The exciting science that can be probed with these new facilities will be highlighted.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSACCELERATORSALKALINE EARTH ISOTOPESALPHA REACTIONSASTROPHYSICSBARYON REACTIONSBERYLLIUM 7BERYLLIUM ISOTOPESBETA DECAY RADIOISOTOPESBETA-PLUS DECAY RADIOISOTOPESCHARGED-PARTICLE REACTIONSCOULOMB FIELDCROSS SECTIONSDAYS LIVING RADIOISOTOPESDECAYELECTRIC FIELDSELECTRON CAPTURE RADIOISOTOPESEVEN-ODD NUCLEIEXTRAPOLATIONGAMMA DECAYHADRON REACTIONSHELIUM 3 TARGETHYDROGEN BURNINGISOTOPESLIGHT NUCLEIMAIN SEQUENCE STARSMATHEMATICAL SOLUTIONSMINUTES LIVING RADIOISOTOPESNITROGEN 14 TARGETNUCLEAR DECAYNUCLEAR PHYSICSNUCLEAR REACTIONSNUCLEINUCLEON REACTIONSNUCLEOSYNTHESISNUMERICAL SOLUTIONOXYGEN 15OXYGEN ISOTOPESPHYSICSPROTON REACTIONSRADIOISOTOPESSIMULATIONSTAR BURNINGSTARSSUNSYNTHESISTARGETSUNDERGROUND FACILITIES

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BibTeXRIS

Bemmerer, Daniel. 2010-08-04. Nuclear Physics Underground. https://doi.org/10.1063/1.3480147

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