An experimental limit on the charge of antihydrogen

C. Amole, M.D. Ashkezari, M. Baquero-Ruiz, W. Bertsche, E. Butler, A. Capra, C.L. Cesar, M. Charlton,S. Eriksson, J. Fajans, T. Friesen, M.C. Fujiwara, D.R. Gill, A. Gutierrez, J.S. Hangst, W.N. Hardy, M.E. Hayden, C.A. Isaac, S. Jonsell, L. Kurchaninov, A. Little, N. Madsen, J.T.K. McKenna, S. Menary, S.C. Napoli, P. Nolan, K. Olchanski, A. Olin, A. Povilus, P. Pusa, C.Ø. Rasmussen, F. Robicheaux, E. Sarid, D.M. Silveira, C. So, T.D Tharp, R.I. Thompson, D.P. van der Werf, Z. Vendeiro, J.S. Wurtele, A.I. Zhmoginov, A.E. Charman