This is a Ludlum Model 44-17 low energy gamma detector.  Typically used for I-129 surveys, but could be used for any low E gamma application.

PART NUMBER: 47-1547

APPLICATION: ¹²⁵I and low energy gamma radiation survey

RADIATION DETECTOR: 2 in. (5.1 cm) diameter X 2mm thick sodium iodide (NaI)Tl scintillator

EFFICIENCY (4π) : 41% – ¹²⁵I (based on ¹²⁹I  efficiency of 18% – learn more)
WINDOW: 43 mg/cm²

ENERGY RANGE: 10-200 keV
ENERGY RESPONSE: energy dependent

BACKGROUND (10 µR/hr): < 1500 cpm

SENSITIVITY: 2500 cpm/µR/hr (¹²⁵I)

RECOMMENDED ENERGY RANGE: 10-200 keV
COMPATIBLE INSTRUMENTS: general purpose radiation survey meters, ratemeters and scalers
PHOTOMULTIPLIER TUBE: 2.0 in. (5.1 cm) diameter
OPERATING VOLTAGE: typically 500-1200 volts
SIZE: 2.6 x 9 in. (6.7 x 22.9 cm) (Dia x L)
WEIGHT: 1.5 lb (0.7 kg)

CE CERTIFIED: yes