The GRIFFIN facility for Decay-Spectroscopy studies at TRIUMF-ISAC

Detailed spectroscopy of Ca46 : A study of the β− decay of KPore1, Andreoiu2, Smith3 et al. 2019Phys. Rev. CSelf Cite60131View full textAdd to dashboardCite

“…A pure beam of 4×10 5 pps 46 K was delivered and implanted into Mylar tape at the center of the GRIF-FIN array. The array was operated with 15 high-purity germanium (HPGe) clover γ-ray detectors [19] (with a HPGe-to-source distance of 11 cm), and was coupled to PACES [17,20], an array of 5 lithium-drifted silicon detectors, operated at liquid-nitrogen temperature, for the detection of conversion electrons placed in the upstream position, and SCEPTAR [17,21], an array of 10 plastic scintillators for β-particle tagging, mounted in the downstream position. A sphere of 20 mm thick Delrin plastic absorber was placed around the vacuum chamber to stop energetic β particles from reaching the HPGe detectors.…”

“…The intensities of the observed γ rays were corrected for summing effects as is discussed in Ref. [17]. Several γ rays from the decay of 46 K were observed at energies greater than 3.2 MeV, so it was necessary to include simulated highenergy efficiency data points based on GEANT4 simulations that were scaled and fitted to the source data [23].…”

“…For γ-ray intensities obtained from the singles events, the fitted peak areas were corrected for summing effects using the empirical method described in Ref. [17].…”

“…Note that it was important to correct N 12 for possible summing effects. This has been done here for coincidence data using a similar method to that discussed for singles data in Ref [17]. In the coincidence case, the summing correction factors are specific to the transition of interest as well as the choice of the gating transition.…”

“…In this article, we present the results of high-statistics data from the β − decay of the J π = 2 − 46 K ground state into 46 Ca collected with the GRIFFIN spectrometer (Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei) [16,17], located at TRIUMF-ISAC [18]. This measurement expands the current knowledge of the 46 Ca level scheme and includes the placement of γ rays from γ-γ coincidence measurements, and spin and parity assignments from the analysis of γ-γ angular correlations in conjunction with calculated logf t values from the observed β feeding and decay systematics within the level scheme.…”