2. Residual dose rates in the FCChh detector
Roxana Rata, Markus Widorski, Stefan Roesler – HSE/RP
5th July, 2017, FCChh Detector meeting

3. Outline Simulations Conceptual design: updated detector geometry
Evaluation of the residual dose rate
Conclusions
5th July, 2017, FCChh Detector meeting

4. Simulations FLUKA simulation to estimate the residual dose rates
Many thanks to I. Besana, EN/STI who provided the geometry and the input file. Geometry and collision parameters remained identical.
Adapted the material compositions
Trial of two materials for the forward shielding: SS317LN and Brass in order to compare if differences in residual dose rates
Dose rates in LS2 (after baseline operation) and LS5 (after ultimate operation) with 6 cooling periods: 8 hours, 1 day, 1 week, 1 month, 4 months and 1 year.
5th July, 2017, FCChh Detector meeting

5. Detector geometry M.I. Besana, FCC week 2017
Cavern: R = 15 m, L = 70 m
5th July, 2017, FCChh Detector meeting

6. Detector geometry Material adapted: Lead SS317 AA6082 C17410 C35300
CSS304L
CSS316L
CSS316LN
YUS130S
P506
KHMN30L
Added radiologically important trace elements
(from ActiWiz database)
TAS
5th July, 2017, FCChh Detector meeting

7. Evaluation of the residual dose rates
LS2 – 1 day of cooling down
LS5 – 1 day of cooling down
5th July, 2017, FCChh Detector meeting

8. LS2 – 1 week of cooling down LS5 – 1 week of cooling down
5th July, 2017, FCChh Detector meeting

9. LS2 – 1 month of cooling down LS5 – 1 month of cooling down
5th July, 2017, FCChh Detector meeting

10. LS2 – 1 year of cooling down LS5 – 1 year of cooling down
5th July, 2017, FCChh Detector meeting

11. Residual dose rates along Z for R=0 .. 20 cm
LS5
LS2
5th July, 2017, FCChh Detector meeting

12. Comparison between SS317LN and Brass shielding: LS2
5th July, 2017, FCChh Detector meeting

13. Comparison between SS317LN and Brass shielding: LS5
5th July, 2017, FCChh Detector meeting

14. Conclusions The residual dose rate was evaluated for the new geometry
For these calculations we considered 5 different cooling periods in LS2 and LS5
No significant differences in residual dose rates where found for SS317 or brass as shielding material for short decay times. Possible beneficial for long decay times.
High radiation levels in forward region; of concern for work on open detector
5th July, 2017, FCChh Detector meeting

16. Comparison Dipole to Solenoid design
Forward dipole (2016)
Solenoid design (2017)
LS2, 1 week
LS5, 1 week
5th July, 2017, FCChh Detector meeting

17. Detector geometry – Shielded areas
Shielding around the forward calorimeter:
1 m of steel
5 cm of lithiated polyethylene
- 1 cm of lead
Shielding in front of the forward calorimeter: 5 cm of polyethylene and 2 mm thick Al covers
Forward muon chambers with cast iron shielding
Cylindrical shielding:
1 m cast iron
-5 cm of polyethylene
1 cm of lead
Conical shielding:
-1 m cast iron
-5 cm of polyethylene
-1 cm of lead
Cast iron shielding layer for the muon chambers
M.I. Besana, FCC week 2017
5th July, 2017, FCChh Detector meeting