New <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi mathvariant="normal">C</mml:mi></mml:mrow><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>13</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow><mml:mo stretchy="false">(</mml:mo><mml:mi>α</mml:mi><mml:mo>,</mml:mo><mml:mi>n</mml:mi><mml:mo stretchy="false">)</mml:mo><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>16</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:mrow></mml:math> Cross Section with Implications for Neutrino Mixing and Geoneutrino Measurements
M. Febbraro, R. J. deBoer, S. D. Pain, Rebecca Toomey, F. D. Becchetti, A. Boeltzig, Y. Chen, K. A. Chipps, M. Couder, K. L. Jones, Edward Lamere, Q. Liu, S. Lyons, K. T. Macon, L. A. Morales, William A. Peters, D. Robertson, B. C. Rasco, K. Smith, C. Seymour, G. Seymour, M. S. Smith, E. Stech, B. Vande Kolk, M. Wiescher
Abstract
Precise antineutrino measurements are very sensitive to proper background characterization. We present an improved measurement of the $^{13}\mathrm{C}(\ensuremath{\alpha},n)^{16}\mathrm{O}$ reaction cross section which constitutes significant background for large $\overline{\ensuremath{\nu}}$ detectors. We greatly improve the precision and accuracy by utilizing a setup that is sensitive to the neutron energies while making measurements of the excited state transitions via secondary $\ensuremath{\gamma}$-ray detection. Our results shows a 54% reduction in the background contributions from the $^{16}\mathrm{O}({3}^{\ensuremath{-}},6.13\text{ }\mathrm{MeV})$ state used in the KamLAND analysis.