Fig. 3: Summed double-γ energy spectrum and data reduction.
From: Electromagnetic character of the competitive γγ/γ-decay from 137mBa
Black data points show the summed energy of two coincident photons detected in the CeBr3 detectors for events with a multiplicity of two. Grey data points show the sum energy spectrum when the multiplicity is larger than two, which mainly correspond to the background induced by cosmic ray showers. We also show the fit to the data of a quadratic background as a dashed red line and the fit of the background plus a Gaussian peak as a solid red line. a Raw data before any conditions. b Reduced data with the condition that the energy difference between two γ rays is \(|{E}_{\gamma ,1}-{E}_{\gamma ,2}|<300\) keV. c Final data with the additional condition that \(|{E}_{\gamma ,1}-{E}_{\gamma ,2}|<960-({E}_{\gamma ,1}+{E}_{\gamma ,2})\) keV to remove the cosmic-ray induced background. The error bars represent the one standard-deviation statistical uncertainty.
