Table 1:

Physical properties and estimated associated desired values for a diarylethene-based scintillator-switchillator detector medium containing both a fast scintillator and the photoswitchable Switchillator molecules [35–38]. Switchillator properties of particular concern and that are targeted for development include the Dye Ratio (selectivity), On-state lifetime (resetting), and Absorption Length (optical depth) [62].

	Parameter	Symbol	Value	Comment
Scintillator Properties
1	Scintillation Yield	Yscint	> 2 × 103	# of scintillation photons per MeV
2	Scintillation Rise Time	τr	TBD	1/e rise time of scintillation light
3	Scintillation Decay Time	τd	TBD	1/e decay time of scintillation light
Switchillator Properties
1	Activation Yield	Yact	> 5 × 103	# of ON fluorophores per MeV deposited
2	Activation Wavelength	λact	< 400 nm	Peak inactive to active wavelength
3	Excitation Wavelength	λex	350–650 nm	At max separation
4	Dye Ratio	Zdye	< 10−12	Ratio of rates of background activation to fluorescence at λex
5	On-State Lifetime	λON	3×10−7–10−1 s	1/e Lifetime of ON fluorophores
6	Fluorescence brightness	ε · Φfl	> 103/(M cm)	Rate of emission from active dye
7	Mean Absorption Length	χ(λex)	> 6 m	1/e absorption length at λex
8	Emission Wavelength	λfl	400–700 nm	Wavelength of fluorescence light
9	# of photons per activated fluorophore	Nfl	> 500	Mean # of fluorescent photons extracted per fluorophore before deactivation