Searching a dark photon with HADES

Publication Type
Journal Article
Year of Publication
Agakishiev, G.
Balanda, A.
Belver, D.
Belyaev, A.
Berger-Chen, J. C.
Blanco, A.
Bohmer, M.
Boyard, J. L.
Cabanelas, P.
Chernenko, S.
Dybczak, A.
Epple, E.
Fabbietti, L.
Fateev, O.
Finocchiaro, P.
Fonte, P.
Friese, J.
Frohlich, I.
Galatyuk, T.
Garzon, J. A.
Gernhauser, R.
Gobel, K.
Golubeva, M.
Gonzalez-Diaz, D.
Guber, F.
Gumberidze, M.
Heinz, T.
Hennino, T.
Holzmann, R.
Ierusalimov, A.
Iori, I.
Jurkovic, M.
Kampfer, B.
Karavicheva, T.
Koenig, I.
Koenig, W.
Kolb, B. W.
Kornakov, G.
Kotte, R.
Krasa, A.
Krizek, F.
Krucken, R.
Kuc, H.
Kuhn, W.
Kugler, A.
Kurepin, A.
Ladygin, V.
Lalik, R.
Lang, S.
Lapidus, K.
Lebedev, A.
Liu, T.
Lopes, L.
Lorenz, M.
Maier, L.
Mangiarotti, A.
Markert, J.
Metag, V.
Michalska, B.
Michel, J.
Muntz, C.
Naumann, L.
Pachmayer, Y. C.
Palka, M.
Parpottas, Y.
Pechenov, V.
Pechenova, O.
Petousis, V.
Pietraszko, J.
Przygoda, W.
Ramstein, B.
Reshetin, A.
Rustamov, A.
Sadovsky, A.
Salabura, P.
Scheib, T.
Schuldes, H.
Schmah, A.
Schwab, E.
Siebenson, J.
Sobolev, Y. G.
Spataro, S.
Spruck, B.
Strobele, H.
Stroth, J.
Sturm, C.
Tarantola, A.
Teilab, K.
Tlusty, P.
Traxler, M.
Trebacz, R.
Tsertos, H.
Vasiliev, T.
Wagner, V.
Weber, M.
Wendisch, C.
Wustenfeld, J.
Yurevich, S.
Zanevsky, Y.
Collaboration, Hades
Name of Publication
Physics Letters B
Date Published
Short Title
Searching a dark photon with HADES
Accession Number
ISBN Number

We present a search for the e(+)e(-) decay of a hypothetical dark photon, also named U vector boson, in inclusive dielectron spectra measured by HADES in the p(3.5 GeV) + p, Nb reactions, as well as the Ar (1.756 GeV/u) KCl reaction. An upper limit on the kinetic mixing parameter squared epsilon(2) at 90% CL has been obtained for the mass range M-U = 0.02-0.55 GeV/c(2) and is compared with the present world data set. For masses 0.03-0.1 GeV/c(2), the limit has been lowered with respect to previous results, allowing now to exclude a large part of the parameter region favored by the muon g - 2 anomaly. Furthermore, an improved upper limit on the branching ratio of 2.3 x 10(-6) has been set on the helicity-suppressed direct decay of the eta meson, eta --> e(+)e(-), at 90% CL. (C) 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license