GIF++ The new Gamma Irradiation Facility at CERN Physics Department Detector Technology Group...

GIF++ The new Gamma Irradiation Facility at CERN

Physics DepartmentDetector Technology Group

29/06/12 R. Fortin PH-DT-DI 1

Procurement of the 10TBq 137Cs Source, Irradiator and Filters

GIF 137Cs measured in 1997: 740 GBq Other characteristics of 137Cs are:Half-life: 30.17 yBeta decay (gamma emission 662 keV) Inquiries carried out in 2009 suggest that the cost of the whole system will be around 300-400 K CHF Given that cost > 200K, a market survey (1+ 2 weeks) followed by a Call for Tender (2 + 4 + 1 weeks) is necessary before contract is awarded. Procurement person: R.Fortin (PH-DT) with vital contributions of CERN Safety and Procurement services




Criteriae defined in 2009

The source was described as:Single 7.4 10 TBq ∼ 137Cs source with it’s “Type B” travel container<< for transportation, fixation, use and service, in case the source will not supplied by the same firm than the radiator and/or on different timescales >> The irradiator was described as:One fully functional irradiator with it’s remote control console<< “Main” panoramic collimator, “Secondary” rear collimator, axis @ 150 cm above the ground, Dose Rate monitors to control the functionality, control room distance 30m… >> The radiation filters were described as:One filter system<< Remote controlled programmable, four vertical slides, attenuation ≥ 1:1 - 10,000:1 >> Retrieval of the old irradiator…This is an option part of the specifications document




2012 replies from identified suppliers

- Three well-established firms (FR+CH+DE) showed interest to provide CERN with the future irradiator of GIF++ after the market survey of 2009.

- The three firms individually presented their project as a package where the Irradiator, Source and Controls were combined according to our specifications document SPSC-P-339.

These 3 candidates were recently asked to reiterate their proposals.

- The French firm will simplify the solution presented late 2010- The German firm may abandon the project- The Swiss firm fulfills our requirements

Updated specifications will be sent to current and new candidates.




The 137Cs Source:(compressed pellets of Caesium chloride)

origin: Eckert & Ziegler Nuclitec GmbH

- Shape of capsule: RSL6030 ( 21.3 x L26.4mm outer ∅dimensions)- The source has a double encapsulation of stainless steel- The source comes in a stainless steel holder according to ISO 4037-1- CERN RP will ensure that the manufacturer of the source applies ISO 2919

- Origin of isotope: Russia ( according to our candidates )- Major distributor: Eckert Ziegler Nuclitec GmbH- Standard intensities: 7.4 TBq & 16.65 TBq (200 Ci & 450 Ci)- Standard delivery: 1 month- Requested intensity : ∼7.4 - 10 TBq (∼200 - 280 Ci)

Such 137Cs sources have a delivery time of 8 to 12 months !<<Raw materials market not transparent… E.Z AG Company analysis 05/31 2000>>




The irradiator for GIF++

The new irradiator should provide:- A pneumatic manipulator for the 137Cs source- Provision to retract and keep the source in “Tresor” position- A steel protected lead shielding providing a residual dose rate <2.5 µSv/h- A “Downstream” rectangular collimator of +/- 37° in the horizontal plane and

+28°/ -14° in Azimuth- A secondary “Upstream” collimator of +/- 10° in the horizontal plane and

azimuth- A set of 3 Dose Rate monitors to control the functionality of the irradiator- A hard wired Operation Console located 30mt away in the Control Room- A mechanical locking device of the source for transportation- A type “ B” container allowing transportation of the source- All necessary tooling to load the source in the irradiator on site if applicable

Cegelec©

Radioactive source Irradiator




The irradiation field with the particle beam inside the bunker

m-beam




Lateral view of the irradiatorand H4 Beam line

Top view of the irradiatorand H4 Beam line




Irrad

iato

r Co

nsol

e

Hard wired Irradiator

connections

Bunker Emergency Stop

Bunker Check Point buttons

Dose Rate Monitors

Compressed air pressure

Source position sensors

Hard wired

CERN

Safety & Infrastructure

Access Control

Gas alarm

Fire alarm

Electrical Power with UPS backup

IR personnel detection

Acceptable Weather contitions

Console controls

Console Emergency Stop

Console ON-OFF key switch

Manual VETO key

Full Operator Interface

Irradiation ONStart of irradiation alarm

Red Yellow Green lights




Characteristics of the Attenuator

3(4) layers of spherically compensated lead filters provide:- Attenuation steps between 1:1 and 1:10,000- Collimation of +/- 37° in the horizontal plane and +28°/ -14° in Azimuth - Homogeneous Dose Rate across the panoramic area- Thick support frame to guarantee sharp boundary cutoff - Maximum attenuation when layers are in ‘bottom’ position

The Attenuator mechanism should:- Be programmable from the Control Room- Move in the vertical axis (floor space constraints ≤ 4mt)- Position the filters by servo motors and counterweights- Stand against the irradiator body to reduce the ‘frames’ of the filters- Carry a safety release to let all layers reach ‘bottom’ position by gravity

The conceptual design and controls of this equipment have been left open for discussion with our bidders.

Two firms showed interest in producing our specific lead filter attenuator.




Retrieval of our irradiator BA102 sold in 1996 by Amersham (CH)

137Cs Source provided by STS (DE)

The original seller agreed to retrieve the irradiator “BA102” after the normal activity period, i.e. between 2005 and 2007 at a fixed cost of 14K CHF.

In the mean time the seller ceased it’s activity in 2002 and another Swiss firm continues the business but has not yet provided an offer for retrieval.

In 2007 retrieval of the irradiator was offered for a price of 56K EUR.

In the light of such variations of cost, we will require from all candidates the assurance to receive prompt service, the evaluation of cost for regular maintenance and how they plan to recuperate the irradiator at the end of its service life.




Conclusion

Procurement plan key dates:

- Early September, 2012 for order sent out,

- 3rd quarter 2013 for delivery.( the full system in GIF++ area )

This schedule allows to commission the facility confortably.

GIF++ The new Gamma Irradiation Facility at CERN Physics Department Detector Technology Group...

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