Accident scenarios for

MTA beam line

Igor Rakhno

June 8, 2007

The scenarios

• Several spatial locations were examined:

– beam pipe 5 m US the 12-ft sh.block;

– beam pipe 2.5m US the 12-ft sh.block;

– beam stop itself;

– beam pipe inside the 12-ft sh.block, ≈ under the penetrations;

– quad 5 m DS the 12-ft sh.block

• The beam stop in all the cases is in upper position (beam pipe is clear).

• Two penetrations are in the model: coax and rectangular (modeled as circular).

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Plan view @ beam line elevation

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Penetrations: elevation view

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Penetrations: plan view @ elevation of X=370 cm

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Calculated dose in the penetrations @ X=370 cm

Location Dose (mrem/pulse)

Beam pipe 5 m US the 12-ft sh.block 1

Beam pipe 2.5m US the 12-ft sh.block 1

Beam stop itself 1

Beam pipe inside the 12-ft sh.block 25

Quad 5 m DS the 12-ft sh.block 240

There is no cross-talk between the penetrations, so that we have

two spots 240 mrem/pulse each, not one spot 480 mrem/pulse.

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Accident on quad; plan view @ X=370 cm

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Accident inside the 12-ft block

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