Search for neutron dark decay: n $\rightarrow \chi + e^+e^-$
| Autor: | Sun, X., Adamek, E., Allgeier, B., Blatnik, M., Bowles, T.J., Broussard, L.J., Brown, M.A.P., Carr, R., Clayton, S., Cude-Woods, C., Currie, S., Dees, E.B., Ding, X., Filippone, B.W., GarcÍa, A., Geltenbort, P., Hasan, S., Hickerson, K.P., Hoagland, J., Hong, R., Hogan, G.E., Holley, A.T., Ito, T.M., Kneckt, A., Liu, C.Y., Liu, J., Makela, M., Mammei, R., Martin, J.W., Melconian, D., Mendenhall, M.P., Moore, S.D., Morris, C.L., Nepal, S., Nouri, N., Pattie, R.W., Galván, A.P., II, D.G.Phillips, Picker, R., Pitt, M.L., Plaster, B., Ramsey, J.C., Rios, R., Salvat, D.J., Saunders, A., Sondheim, W., Sjue, S., Slutsky, S., Swank, C., Swift, G., Tatar, E., Vogelaar, R.B., Vorndick, B., Wanchun, W., Wang, Z., Wexler, J., Womack, T., Wrede, C., Young, A.R., Zeck, B.A. |
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| Přispěvatelé: | Institut Laue-Langevin (ILL), ILL |
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
energy: kinetic
branching ratio: upper limit n: decay n: branching ratio talk: Grenoble 2018/05/24 calibration dark matter mass dependence electron: pair production [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex] High Energy Physics::Experiment n: lifetime acceptance experimental results |
| Zdroj: | EPJ Web Conf. International Workshop on Particle Physics at Neutron Sources 2018 International Workshop on Particle Physics at Neutron Sources 2018, May 2018, Grenoble, France. pp.05008, ⟨10.1051/epjconf/201921905008⟩ |
| DOI: | 10.1051/epjconf/201921905008⟩ |
| Popis: | International audience; In January, 2018, Fornal and Grinstein proposed that a previously unobserved neutron decay branch to a dark matter particle (χ) could account for the discrepancy in the neutron lifetime observed in two different types of experiments. One of the possible final states discussed includes a single χ along with an e+e− pair. We use data from the UCNA (Ultracold Neutron Asymmetry) experiment to set limits on this decay channel. Coincident electron-like events are detected with ∼ 4π acceptance using a pair of detectors that observe a volume of stored Ultracold Neutrons (UCNs). We use the timing information of coincidence events to select candidate dark sector particle decays by applying a timing calibration and selecting events within a physically-forbidden timing region for conventional n → p + e- + ν̅e decays. The summed kinetic energy (Ee+e−) from such events is reconstructed and used to set limits, as a function of the χ mass, on the branching fraction for this decay channel. |
| Databáze: | OpenAIRE |
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