OSSE observations of the 4 June 1991 solar flare

We present time profiles of the 2.223 MeV neutron‐capture line and the 4.44 MeV 12C nuclear‐deexcitation line derived from observations of the 4 June 1991 X12+ solar flare obtained by the Oriented Scintillation Spectrometer Experiment (OSSE) on board the Compton Gamma‐Ray Observatory (CGRO). We discuss the OSSE instrument, the solar observation mode used during the June period, the data analysis technique employed, and derive an estimate of the accelerated‐particle spectrum and a lower limit to the number of interacting particles.