Scintillation crystal including a co-doped rare earth silicate, a radiation detection apparatus including the scintillation crystal, and a process of forming the same

A scintillation crystal comprising a rare earth silicate, a first dopant, and a second dopant, wherein:

• the first dopant is an activator and has a first concentration;
• the second dopant includes a Group 2 element and has a second concentration that does not exceed 200 ppm atomic based on a total rare earth content of the scintillation crystal;
• and
• the scintillation crystal has a decay time no greater than 40 ns.

A process of forming a scintillation crystal comprising:

• charging a crucible with an initial mass of a material for the scintillation crystal that includes a rare earth silicate, a first dopant, and a second dopant, wherein:
• the first dopant is an activator and has a first concentration;
• and
• the second dopant is a Group 2 element;
• melting the charge to form a melt that includes a rare earth silicate, a first dopant, and a second dopant, wherein:
• the first dopant has a first concentration in the melt;
• the second dopant has a second concentration in the melt that does not exceed 0.25 at % based on a total rare earth content of the melt;
• and
• the second atomic concentration divided by the first atomic concentration is in a range of 0.4 to 2.5;
• growing a boule from the melt;
• and
• cutting the boule to obtain a scintillation crystal.