Crystal Growth and Characterization of Europium-Doped Rubidium Calcium Bromide Scintillators

National security strategies like gamma spectroscopy and high-energy X-ray radiography are limited, in part, by the scintillator used, prompting research into novel materials with improved properties. In this work, Eu
$^{2+}$
activated rubidium calcium bromide scintillators were grown via the vertical Bridgman method with a range of dopant concentrations. Light yield, energy resolution, and the afterglow of Rb
₄
CaBr
₆
:Eu and RbCaBr
₃
:Eu improved with increasing Eu
$^{2+}$
concentration, and scintillation decay time increased. The highest light yields of Rb
₄
CaBr
₆
:Eu and RbCaBr
₃
:Eu were 71000 and 45000 ph/MeV, respectively.