67 Cu Production in Gallium Cu Production in Gallium 67 George - - PowerPoint PPT Presentation

67 67Cu Production in Gallium

Cu Production in Gallium


George Kharashvili Radiation Physics, RadCon 4/14/17

Previous Test of 67Cu Production in Ga

• 4D beamline
• Beam test plan described

in ATLis 16434

• RWP #2016-J004
• Ga and Zn targets
• 56 MeV, 89 nA, 5 min
• Samples replaced

– No notable radiological concerns

• 18.5 MeV, 2.5 µA, 1 h
• 1 R/h on contact dose rate minutes after irradiation
• Samples removed 20 hours after the irradiation
• Tungsten radiator was the most radioactive item
• Did not create notable radiological concernes, stored for decay

Results of the Previous Test

• Possible reasons causing the

Possible reasons causing the discrepancies: discrepancies: – Imperfect target alignment Imperfect target alignment – How well the beam energy and the beam How well the beam energy and the beam energy spread were known energy spread were known – Issues with the model Issues with the model

Target Measured 67Cu Yield [Bq/W-h] FLUKA 67Cu Yield [Bq/W-h] Ratio FLUKA/Meas. Ga 111 ± 18 228 ± 7 2.05 ± 0.33 Zn 103 ± 17 75.7 ± 3.3 0.73 ± 0.12

New Experiment New Experiment

• Produce enough

Produce enough 67

67Cu for

Cu for radiochemical separation radiochemical separation – 100s 100s

• f µ
• f µCi

Ci

• Measure radiochemical separation

Measure radiochemical separation efficiency at VCU efficiency at VCU

• Provide additional/more reliable

Provide additional/more reliable data point for validating the data point for validating the FLUKA and TALYS models FLUKA and TALYS models

Irradiation Parameters Irradiation Parameters

• Ee- = 18.5 to 18.65 MeV

= 18.5 to 18.65 MeV – Avoid incident photons above 18.59 MeV Avoid incident photons above 18.59 MeV in in Ga Ga ( (67

67Ga production threshold,

Ga production threshold, interfears interfears with measurement) with measurement)

• Energy spread:

Energy spread: σE = 50 = 50 keV keV

• Beam power: P = 1 kW

Beam power: P = 1 kW

• Beam size:

Beam size: σ = 2.5 mm = 2.5 mm

• Irradiation time

Irradiation time – Minimum: 48 hours Minimum: 48 hours – 42% of 42% of Asaturation

saturation

– Optimal: > 72 hours Optimal: > 72 hours – 55% of 55% of Asaturation

saturation

• Radiator

Radiator 1 mm W 1 mm W

• Target

Target 85 g natural gallium in 85 g natural gallium in hBN hBN capsule capsule

Setup model

Be Window W radiator hBN Capsule Ga Target

Prompt Radiation Field Prompt Radiation Field

• 3/10/14 4D spectrometer dump shielding

3/10/14 4D spectrometer dump shielding commissioning test commissioning test

– ATLis ATLis 13446 13446 – Surveys during 123 MeV, 100 µA Surveys during 123 MeV, 100 µA – 5 µrem/h of neutron dose rate and 80 µrem/h 5 µrem/h of neutron dose rate and 80 µrem/h photon dose rate were measured in north photon dose rate were measured in north access building access building – Radiological conditions were found acceptable Radiological conditions were found acceptable – Neutron source term Neutron source term 85 ± 3 rem/h at 1m from the dump 85 ± 3 rem/h at 1m from the dump

• 18.5 MeV test will produce the same neutron

18.5 MeV test will produce the same neutron sourceterm sourceterm if beam power equals if beam power equals 1.1 kW 1.1 kW

• Additional shielding not required

Additional shielding not required

Experimental Procedure

• 1. Remove W radiator
• 2. Position poly block (“dummy target”) with radiochromic

film on both ends

• 3. Close side cooling plates
• 4. Beam permit
• 5. Tune beam for 5 minutes

– Observe with camera

• 6. Controlled access
• 7. Check position / align / repeat if necessary
• 8. Install W radiator
• 9. Beam Permit
• 10. Run CW for 48 to 72 hours

Power Deposition per kW of Beam

Part Power [W] Be Window 6 W Radiator 280 hBN Capsule 355 Ga Target 233 Cu Cooling 27 Total 901

Induced Radioactivity Induced Radioactivity

Beam Energy 18.5 MeV 18.65 MeV Irradiation Time 48 h 380 µCi Ci 465 µCi Ci 72 h 510 µCi Ci 620 µCi Ci Expected 67Cu activities in Ga, 1 day after the irradiation

Post-Irradiation Dose Rates Post-Irradiation Dose Rates

Dose Rates [mrem/h] at 30 cm for E=18.6 MeV Decay time [h] 1 12 24 Full setup 3050 190 100 Target only (hBN capsule + Ga) 1770 6.2 2.4