1. Development of a standard library of background simulation codes
JRA1
WP2
Development of a standard library of background simulation codes
The second WP inside the joint research activity 1 of ILIAS about Low background Techniques for Deep underground Science is devoted to the Development of a standard library of background simulation codes in close connection to the other WP whose main objective is to measure environmental background, radioactivity of materials and to collect data.
We could summarize the objectives in a few words: the creation of a coherent and well tested library of MC codes available for all the users of the underground labs.

2. Special Cross-links JRA1-WP2 JRA2(IDEA) WP3-B1 N3-BSNS
Development of a standard
library of background
simulation codes
JRA2(IDEA)
WP3-B1
N3-BSNS
Background
Simulation,
Neutron-Shield
and Muon-Vetos
Study on
Cosmogenic
Induced Activity
Of course, this working group will be working together with the other WP of JRA1, but we should also share simulation works and activities with the WP (Background simulation and neutron shielding) of the network N3 on Dark Matter and with the WP-B1 (materials activation simulation) of JRA2( Integrated double beta decay)
05/04/2019
Modane_Jan Gloria Luzón (LSC)

3. Planning for the first year
Existing codes compared and discussed.
Platform, language and structure of the library fixed.
First set of MC codes for relevant background components and instrumentation ready.
Tasks
Milestones and deliverables
First “test” version of MC libraries implemented.
Technical report prepared.
The first year we are collecting the most used codes. We must compare the codes ( with experimental data and also with other codes) and discuss these results.
We have also to agree a platform, language and structure for the library of codes where to locate the first set of MC codes.
The deliverables of this year will be a first version of MC libraries and a technical report.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

4. Progress of the work Task A: Existing codes compared and discussed.
Task B: Platform, language and structure of the library fixed.
Task C: First set of MC codes for relevant background components and instrumentation ready.
Now, I will talk about the progress of the work.

5. Modane_Jan05 Gloria Luzón (LSC)
Task C: First set of MC codes for relevant background components and instrumentation
Alpha, beta and gamma.
Muons and neutrons.
Other codes.
For this task we should agree on a first set of MC codes.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

6. Alpha, beta and gamma background
Widely used GEANT4
Advanced example for underground physics
Most of the standard codes are quite fair to handle the alfa, beta and gamma interactions.
Maybe the most widely used is GEANT4 developed in CERN. In the web page and in the documentation you can even find an Advanced example for underground physics
05/04/2019
Modane_Jan Gloria Luzón (LSC)

7. Neutron background Measurement n at lab
Rate and spectrum for 238U fission and (a,n)
n flux and spectrum at lab
counting rates at detector
rock activity
For neutrons the situation is more complicated.
Let us consider the case of neutrons coming forma radioactivity of the rock:
Now we are using SOURCES (form LANL) to compute the rate and spectrum of the fission and (a,n) processes
MCNP (TUM, Lyon, Saclay and others) or FLUKA (Sheffield, TUM, Milan, Zaragoza) to simulate the neutron propagation and GEANT4 (Sheffield, RAL, ICL, Zaragoza, Milan) to study the neutron interactions. So we will obtain the n flux and spectrum at lab which could be tested in experimental measurements. It is necessary again to use MCNP and GEANT (propagation and interaction) to calculate the counting rates at detector (new test).
Theory
Calculation
SOURCES
FLUKA
MCNP
GEANT4
FLUKA
MCNP
GEANT4
05/04/2019
Modane_Jan Gloria Luzón (LSC)

8. Muon induced neutron background
Measurement muons at lab
Flux and spectrum for muons under-ground
Flux and spectrum of induced neutrons
counting rates at detector
muons
Calculation
MUSIC, MUSUN, SIAM,
FLUKA
For neutrons induced by muons we are using even more codes.
Given a sea-leel flux of muons, the codes MUSIC, MUSUN, SIAM and FLUKA calculate the underground flux of muons. Here we should carried out experimental measurements at lab. FLUKA (and probably GEANT4) can be used to get the flux and spectra of induced neutrons known the muon flux (or vice versa). Finally, again MCNP, FLUKA and GEANT4 for the transport in materials and interactions in the detector.
FLUKA
modified -GEANT3
GEANT4
MCNP
GEANT4
GEANT3
FLUKA
05/04/2019
Modane_Jan Gloria Luzón (LSC)

9. Modane_Jan05 Gloria Luzón (LSC)
Other codes
Cosmogenic induced activity
IDEA web- page
Another source of internal contamination is the induced activity by sea-level cosmic rays (cosmic neutrons mainly) which could take years to disappear .
The study of these codes has been undertaken inside the JRA2 (IDEA) by the WP3-B1.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

10. Task A: comparison of codes
Comparison experimental results.
Comparison of codes.
Modifications to codes.
For the comparison of codes I will just mention some results since in the next talk Vitaly will show you a complete review on the status of the art.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

11. Comparison experimental results
Published neutron flux measurements at Gran Sasso, Modane, Canfranc, CPL (Korea) and others.
Measurements of muon-induced neutrons at various depths underground: neutron yields, energy spectra, lateral distributions etc.: LVD, KARMEN, LSD etc.
Measurements of muon-induced neutrons using active vetoes for dark matter detectors (existing and planned): Canfranc, Modane, Boulby, Gran Sasso.
Planned background flux measurements at Gran Sasso, Modane, Canfranc, Boulby as proposed in JRA1 (ILIAS).
On the transparency you can see experimental results which have been compared to simulations.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

12. Modane_Jan05 Gloria Luzón (LSC)
Comparison of codes
MCNP and GEANT4
Neutrons from rock, propagation and detection.
Need of a comparison using the same geometry and incident spectrum.
Modified GEANT3 and FLUKA
Muon-induced neutrons  good agreement.
GEANT4 and FLUKA
Muon-induced neutrons: yield, spectrum, lateral distribution, and dependence with material.
Comparison of different models of the codes.
Higher production with FLUKA in most materials.
Sea-level neutrons.
GEANT4 shows an underproduction.
MUSIC, MUSUN, SIAM and FLUKA ?
Simulation results with different codes have been also compared.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

13. Modifications to codes
SOURCES
Removal of the 6.5 MeV upper limit for alphas.
New cross-section added and some cross sections updated according to data.
GEANT3
Correction for photonuclear cross-section.
Good agreement with FLUKA results.
Note also than some people have been working on modifications of codes.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

14. Task B: Platform, language and structure of the library
Web page and ftp-site.
Further discussion.
For the task B, we should fix the platform, language and structure of the library.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

15. Structure of the library
General information about codes and links to code web-site.
Modifications to codes.
Library of examples utilized by Underground groups.
Under password
We think that this library should contain information, links, modifications and examples. Of course it will be available only for ILIAS users.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

16. Modane_Jan05 Gloria Luzón (LSC)
Web page and ftp site
The web page for the working group is located at the main JRA1 site
It contains
information about the code comparison and “evaluated” results.
A code ftp repository containing modified programs and examples.
Links to WP1, WP3-4 for data.
List of publications.
A Web page has been created. This web page and the ftp site will be available in the following weeks.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

17. Modane_Jan05 Gloria Luzón (LSC)
Further discussion
Today is a good opportunity to talk about this subject.
Any comment/suggestion will be welcome.
We should dynamize the distribution list devoted to simulations.
Any comment/ suggestion on the structure of the library will be welcome. We could use the distribution list for this purpose.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

18. Milestones and deliverables of the first year
First “test” of MC libraries.
ftp repository.
Technical Report.
Publications
Let’ s come back to the milestones and deliverables we agreed for this first year.
As I have shown you we have achieved the objectives of the WP for the year.

19. First “test” of MC library
We have identified the tasks for which each code is suitable.
We have compared simulations results of different codes .
We have reported on problems, bugs and open questions.
Important meeting held in Edinburgh last September.
A Mid-term report was sent to JRA1 coordinator.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

20. Modane_Jan05 Gloria Luzón (LSC)
FTP repository
We accept any suggestion about this site.
Please send a message asking for the password to
05/04/2019
Modane_Jan Gloria Luzón (LSC)

21. Modane_Jan05 Gloria Luzón (LSC)
Technical report
A technical report is under preparation.
We have examined
Physic models (specially for neutrons and muons): processes, data libraries, energy ranges, …
Geometry capabilities.
Biasing options (to save CPU time)
Energy detection capabilities: nuclear recoil?
Support, availability of code source
Comparison to experiments …
05/04/2019
Modane_Jan Gloria Luzón (LSC)

22. Modane_Jan05 Gloria Luzón (LSC)
Publications
H. Wulandari et al. Proceedings of IDM2002.
G. Chardin and G. Gerbier. Proceedings of IDM2002.
V. Kudryavtsev et al. Proceedings of IDM2002 (York, UK, 2-6 September 2002), p. 476.
V. A. Kudryavtsev et al. NIM in Phys. Res. A, 505 (2003) 688.
G. Gerbier et al, Nucl. Phys. B (Proc. Suppl.) 138 (2005)
S. Cebrian et al, Nucl. Phys. B (Proc. Suppl.) 138 (2005)
H. Wulandari. PhD thesis – TUM (2003).
H. Wulandari et al, hep-ex/
J. M. Carmona et al. Astr Phys. 21 (2004)
M. J. Carson et al. Astr. Phys. 21 (2004) 667.
H. Wulandari et al, Astrop. Phys 22 (2004) 313.
P. F. Smith et al, Astrop.Phys. 22 (2004) 409.
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Modane_Jan Gloria Luzón (LSC)

23. Modane_Jan05 Gloria Luzón (LSC)
H. M. Araujo et al, submitted to Nucl. Instrum. Meth. A, hep-ex/
G.Luzón. Talk at IDM-2004; see IDM-2004 web-site.
H. Mengetti. Talk at IDM-2004; see IDM-2004 web-site.
C. Cozzini. Talk at IDM-2004; see IDM-2004 web-site.
J. McMillan. Talk at IDM-2004; see IDM-2004 web-site.
H. Wulandari . Talk at IDM-2004; see IDM-2004 web-site.
S. Scholl. Talk at IDM-2004; see IDM-2004 web-site.
M. Bauer. Talk at IDM-2004; see IDM-2004 web-site.
M. Carson. Talk at IDM-2004; see IDM-2004 web-site.
J. Davies. Talk at IDM-2004; see IDM-2004 web-site.
H. Araújo and V. Kudriavtsev. Talk at IDM-2004; see IDM web-site.
V. Kudriavtsev. Talk at LBT (SNO).
As you can see after the publications list up to now, there is a great activity on the field.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

24. Plan of work for the next months
Comparison to experimental data.
Benchmarks.
Next simulation meeting JRA1(WP2)-N3(BSNS).

25. Comparison experimental data
To compare, if possible, simulation results of each code with available experimental data.
To use the JRA1-WP1, WP3-4 data on background contributions to compare with codes simulations.
05/04/2019
Modane_Jan Gloria Luzón (LSC)

26. Inputs for the simulations: from JRA1/N2
Measurement n at lab
Measurement n at lab
Rate and spectrum for 238U fission and (a,n)
n flux and spectrum at lab
counting rates at detector
rock activity
rock activity
Theory
Calculation
SOURCES
MCNP
GEANT4
MCNP
GEANT4
05/04/2019
Modane_Jan Gloria Luzón (LSC)

27. Outputs from the simulations: to check
n flux and spectrum before detector
Measurement n at lab
Rate and spectrum for 238U fission and (a,n)
Rate and spectrum for 238U fission and (a,n)
n flux and spectrum at lab
n flux and spectrum at lab
counting rates at detector
counting rates at detector
rock activity
Theory
Calculation
SOURCES
MCNP
GEANT4
MCNP
GEANT4
05/04/2019
Modane_Jan Gloria Luzón (LSC)

28. Outputs from the simulations: to check
n yields
Measurement muons at lab
n flux and spectrum before detector
Flux and spectrum for muons under-ground
Flux and spectrum for muons under-ground
Flux and spectrum of induced neutrons
Flux and spectrum of induced neutrons
counting rates at detector
counting rates at detector
muons
Calculation
MUSIC, MUSUN, SIAM,
FLUKA
FLUKA
modified -GEANT3
GEANT4
MCNP
GEANT4
GEANT3
FLUKA
05/04/2019
Modane_Jan Gloria Luzón (LSC)

29. Modane_Jan05 Gloria Luzón (LSC)
Benchmark
Could we fix a few benchmarks?
The distribution list can be used with this goal.
Group
Process
codes
Exp.
LSC
(n, 2n) in shielding materials
FLUKA, GEANT
CAST (TPC chamber) …
05/04/2019
Modane_Jan Gloria Luzón (LSC)

30. Next meeting on simulation activities.
To be held in Valencia (SPAIN) in March.
Fixed date?
05/04/2019
Modane_Jan Gloria Luzón (LSC)