Radiation Protection aspects LSS1/5 TANs

RADIATION PROTECTION ASPECTSLSS1/5 TANSCristina Adorisio, Kurt Weiss (CERN - DGS/RP)

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2OUTLINE

Residual dose rate measurements February 2012 (Xmas Shutdown): TAN+ZDC detector

Evolution of activationPrediction for 2012 and LS1

Conclusions

TAN- LSS1L

1.5µSv/h 6.3µSv/h

2.1µSv/h

5µSv/h 1.2µSv/h

6.7µSv/h

6.4µSv/h

5.4µSv/h155µSv/h @ vacuum chamber

RP measurements done on February 1st 2012All values at contact

585µSv/h @ vacuum chamber 879µSv/h @ vacuum chamber

Thanks to: K. Weiss (CERN DGS/RP)

1

1

2 3 54To ARC To IP1

CR-0

0161

7

CR-0

0161

6

CR-0

0161

5

CR-0

0161

8

450 µSv/h 550 µSv/h 603 µSv/h 500 µSv/h 125 µSv/hValues measured after removal of the ZDC, at the bottom of the TAN crack

310 µSv/h 300 µSv/h

180 µSv/h

150 µSv/h

2.6 µSv/h(left)

1.3 µSv/h (right)

2 µSv/h (back)

1.3 µSv/h(front) 2

440 µSv/h70 µSv/h@10cm13 µSv/h@40cm

320 µSv/h

200 µSv/h

215 µSv/h

2.6 µSv/h 1.6 µSv/h

1.6 µSv/h

1.7 µSv/h

3


370 µSv/h

245 µSv/h

5


180 µSv/h

170 µSv/h

TREC identifiers


TAN- LSS1R

4µSv/h

2.7µSv/h6µSv/h

6µSv/h

1.6µSv/h

5µSv/h

1.6µSv/h

1.7µSv/h (*)

10µSv/h

(*)

RP measurements done on Febuar 17 th 2012All values at contact

438µSv/h @ vacuum chamber

84µSv/h @vacuum chamber


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1

2 3 54To IP1 To ARC

CR-0

0167

0

CR-0

0166

8

CR-0

0166

9

CR-0

0166

7

77µSv/h 312 µSv/h 423 µSv/h 450 µSv/h 360 µSv/hValues measured after removal of the ZDC, at the bottom of the TAN crack


180 µSv/h

180 µSv/h

1.6 µSv/h(left)

1.6 µSv/h (right)

2.2 µSv/h (back)

1.6 µSv/h(front) 3

320 µSv/h34 µSv/h@10cm5 µSv/h@40cm

310 µSv/h

260 µSv/h

300 µSv/h


2.0 µSv/h

1.7 µSv/h

4


220 µSv/h

180 µSv/h

5


144 µSv/h

150 µSv/h

TREC identifiers


1.7 µSv/h

1.4 µSv/h


1.3 µSv/h

1 µSv/h


TAN- LSS5L

1.4µSv/h 8µSv/h

2.1µSv/h

9µSv/h

1.3µSv/h

8µSv/h

540µSv/h @ buttom of crack

3.3µSv/h

8µSv/h

RP measurements done on February 6 th 2012All values at contact


1

1

32To ARC To IP5

340 µSv/h 590 µSv/h 340 µSv/h 340 µSv/h 140 µSv/hValues measured after removal of the ZDC, at the bottom of the TAN crack

3 µSv/h (back)

2 µSv/h(front)

3

100 µSv/h @ sides

150 µSv/h

90 µSv/h

3 µSv/h (back) 2 µSv/h (back)

3 µSv/h(front)

2 µSv/h(front)

200 µSv/h (back) 520 µSv/h (back) 180 µSv/h (back)

270 µSv/h(front)

130 µSv/h(front)

130 µSv/h(front)

100 µSv/h @ side

Thanks to: K. Weiss (CERN DGS/RP) RP measurements done on February 6 th 2012All values at contact

ZDC detector (5L)

TAN- LSS5R

8µSv/h

4µSv/h11.5µSv/h

8µSv/h

1.5µSv/h

9.5µSv/h 0.5µSv/h

1.7µSv/h (*)

8.3µSv/h

(*)

RP measurements done on February 6 th 2012All values at contact

573µSv/h @ buttom of crack


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2EVOLUTION OF ACTIVATION

Year of operation 2010 2011 2012

Number of days physics 39 129 210

Energy (TeV) 3.5 3.5 4.0

Fraction of nominal beam intensity 13% 50% 50%

Number of bunches 368 1320 1320

Peak luminosity (cm-2s-1) 1.0×1032 3.5×1033 6×1033

Integrated luminosity (fb-1) 0.05 5.7 15

Source: M. Lamont

The measurements could be used to estimate the residual dose rate during the TS in 2012 and the LS1

Referring to Feb. 2012 detailed measurements done on TANs and on the detectors, the scaling factors are:

8 for 2012 TS4 (Oct. 2012) → essentially driven by the peak luminosity (factor of 2 with respect to the last TS in 2011) and derived from the different cooling time (factor 4 from 3 months cooling time to 1 week cooling time)

3 for LS1 → essentially driven by the integrated luminosity

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2FUTURE SITUATION – 2012 TS4 AND LS1

Residual dose rate (maximum values) on contact (mSv/h)

LSS5February 6th

2012

TS4October 22nd

2012 (Feb.2012 x fact

8)

LS1February 2013

(Feb.2012 x fact 3)

TAN (top) 11.5 92 35

TAN (side) 2.1 17 6

ZDC 520 4160 1560

LSS1February 6th

2012

TS4October 22nd

2012 (Feb.2012 x fact

8)

LS1February 2013

(Feb.2012 x fact 3)

TAN (top) 10 80 30

TAN (side) 2.1 17 6

ZDC 460 3680 1380

→ Higher values are expected for the Cu/SS bars

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A B C D E

Pos.Distance

to IP5 (cm)

Ambient dose equivalent rate in µSv/h for the cooling time

1 hour 8 hours 1 day 1 week 1 month 4 months

A 3045 1819 ±2% 872 ±2% 603 ±3% 315 ±3% 167 ±3% 78 ±4%

B 4515 702 ±3% 423 ±5% 323 ±5% 198 ±5% 117 ±5% 56 ±5%

C 6015 660 ±3% 264 ±5% 155 ±6% 59 ±9% 30 ±8% 16 ±10%

D 9825 21 ±12% 8 ±21% 6 ±26% 3 ±36% 2 ±43% 0.7 ±41%

E 14145 972 ±2% 526 ±3% 392 ±3% 239 ±3% 155 ±3% 64 ±4%

FUTURE SITUATION – LHC NOMINAL M. Fuerstner et al., EDMS 1006918 Calculation done considering 109 7 TeV pp/s for 180 days

(~1 year @ nominal beam energy and intensity)

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2FUTURE SITUATION – LHC NOMINAL

~ 0.6 mSv/h ~ 0.2 mSv/h

Calculation done considering 109 7 TeV pp/s for 180 days are very conservative, scaling the results to a more realistic scenario:

TANLSS5

February 6th 2012

TS4October 22nd

2012 (Feb.2012 x fact

8)

LS1February 2013

(Feb.2012 x fact 3)

Last TS 2015

Residual dose rate

(mSv/h)

2.1 17 6 90

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2CONCLUSIONS

The residual dose rate measurements show No differences from L to R Comparable values in IR5 and in IR1 ZDC detectors values confirm the need of a remote

handling tool also in IR5 to manage the exchange ZDC/bars

The evolution of the activation can be estimated Based on the simulation results Based on the evolution of the operational parameters

The residual dose rate expected in the last TS in 2012 is 8 times higher than in Feb. 2012

The residual dose rate in LS1 (3 months of cooling) is 3 times higher than in the last Xmas stop

THANK YOUFOR YOUR ATTENTION!

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2ALARA

Optimization is a legal requirement if accumulated individual dose exceeds 100 μSv/year (ALARA)

Optimization includes

• work coordination• work procedures• handling tools• design • material

requiredoptional

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2WORK PLANNINGAt present, sharepoint-based RP tool for work approval In future directly linked to the overall LHC work planning approval and access permission tools

Documents

Radiation Protection aspects LSS1/5 TANs