Complete results for five years of GNO solar neutrino observations

Abstract We report the complete GNO solar neutrino results for the measuring periods GNO III, GNO II, and GNO I. The result for GNO III (last 15 solar runs) is [ 54.3 −9.3 +9.9 ( stat ) ± 2.3 ( syst ) ] SNU ( 1 σ ) or [ 54.3 −9.6 +10.2 ( incl. syst ) ] SNU (1 σ ) with errors combined. The GNO experiment is now terminated after altogether 58 solar exposure runs that were performed between 20 May 1998 and 9 April 2003. The combined result for GNO (I + II + III) is [ 62.9 −5.3 +5.5 ( stat ) ± 2.5 ( syst ) ] SNU (1 σ ) or [ 62.9 −5.9 +6.0 ] SNU (1 σ ) with errors combined in quadrature. Overall, gallium based solar observations at LNGS (first in GALLEX, later in GNO) lasted from 14 May 1991 through 9 April 2003. The joint result from 123 runs in GNO and GALLEX is [ 69.3 ± 5.5 ( incl. syst ) ] SNU (1 σ ). The distribution of the individual run results is consistent with the hypothesis of a neutrino flux that is constant in time. Implications from the data in particle- and astrophysics are reiterated.