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CERN ITN. Radiation protection and radiation safety issues for HIE-ISOLDE. FLUKA calculations . Y. Romanets. ISOLDE Workshop and Users meeting 2010 CERN, 8 December 2010. Summary. Geometry Installation Targets’ areas HRS (High Resolution Separator) GPS (General Purpose Separator)
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CERN ITN Radiation protection and radiation safety issues for HIE-ISOLDE. FLUKA calculations Y. Romanets ISOLDE Workshop and Users meeting 2010 CERN, 8 December2010
Summary • Geometry • Installation • Targets’ areas • HRS (High Resolution Separator) • GPS (General Purpose Separator) • Targets configuration • Dose rate simulations (FLUKA) • Parking area • Gas storage • On-going work • Conclusions
ISOLDE facility, geometry Ta (Tantalum) target Density 16.654 g/cm3 Target geometry 50 m 40 cm 40 cm GPS HRS UCx (Uranium Carbide) Density 3.25 g/cm3 Target Target Target Plane z=0 Beam direction Proton beam 50 m
Simulation • Bias • ON/OFF • Selected bias direction • Proton beam characteristics • Energy: 1.4 GeV and 2 GeV • Normalization to 1 µA (6.24e12 protons/second)
Simulations, HRS Tungsten convertor + Tantalum target Neutron flux, plane z ( -10cm : +10cm ) Bias OFF Bias ON
Simulations, HRS Tungsten convertor + Tantalum target Bias region Neutron flux, plane z ( -400cm : +400cm ) Neutron flux, plane z ( -400cm : +400cm )
Dose rate, HRSParking area Plane Z=0 No target case. Direct impact of the beam on the beam dump The worst scenario from the radioprotection point of view HRS target HRS beam dump -20 -10 0 10 20 Parking area Y Concrete wall Earth, beam dump shielding X -20 -10 0 10 20
Dose rate, HRSParking area 14 m 18 m 18 m 16 m Y Z Plane Z Plane X X Y 14 m Parking area 14 m Z 2 GeV proton beam Dose-EQ (µSv/h/µA) Plane Y X
Dose rate, GPSGas storage Plane Z=0 GPS target GPS beam dump -20 -10 0 10 20 Gas storage UC and Ta target cases. The scenario for the most used targets Y X -20 -10 0 10 20
Dose rate, GPSGas storage 1.4 GeV proton beam Dose-EQ (µSv/h/µA), Plane Z Tantalum target Gas storage UC target
Neutron production rate, GPS 100 10 1 0.1 0.01 1.4 GeV proton beam Ta target UC target Neutron flux 1e-12 1e-10 1e-8 1e-6 1e-4 1e-2 1 1e2 GeV
On-going work • Comparison of simulation results with measurements • Simulation of the critical parts of the installation. Evaluation of possible impact of upgrade on existing shielding • Activation calculation of the shielding-soil and air inside installation.
Conclusions • The GPS area needs more attention from the radiation protection point of view taking into account upcoming upgrade of the installation. The dose rate of the adjunctive and supply areas depends on the type(material) of the target in use. • HRS area represent sufficient beam dump shielding which is adequate to support increasing power of the beam due upgrade. • Some part of the installation (shielding between active zone and experimental area) need to be revised with more precision due possible radiation leaks
Proton flux, GPS 1000 100 10 1 0.1 1.4 GeV proton beam Ta target Proton flux UC target 1e-2 1e-1 1 GeV