1. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 1 Reminder of goals Reminder of goals Present status Present status Work in progress Work in progress JRA1. LBT-DUSL Low background techniques for deep underground sciences

2. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 2 Key objectives - To identify and measure experimental background components - To design methods and techniques to suppress them Working packages WP1 – Measurement of backgrounds in the EU underground labs WP2 – Development of a library of background simulation codes WP3 – R&D for UL background techniques and facilities in the labs WP4 – R&D on radio-purity of materials and purification techniques Links to: N3 (DMD), N4 (DBD), JRA2 (IDEA)

3. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 3 Management structure of JRA1 Activity coordinatorsJulio Morales/José M. Carmona (LSC) Deputy coordinatorNicola Ferrari (LNGS) WP1. Background measurements in the deep underground sites: CoordinatorNicola Ferrari (LNGS) Deputy coordinatorsMarisa Sarsa/Gloria Luzón (LSC) WP2. Background simulations: CoordinatorGloria Luzón/Susana Cebrián (LSC) Deputy coordinatorVitaly Kudriavtsev (IUS) WP3. Low background facilities: CoordinatorMatthias Laubenstein (LNGS) Deputy coordinatorJean Louis Reyss (LSM) WP4. Radiopurity of the materials: Coordinator:Pia Loaiza (LSM) Deputy coordinator:Lino Miramonti (LNGS)

4. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 4Participants WPLNGSLSMLSCBoulby WP1- Background measurements and monitoring in the deep underground sites N. Ferrari A. Ianni C. Broggini C. Cattadori W. Plastino C. Vignoli G.L. Raselli A. Cesana J. Kisiel L. Miramonti G. Gerbier D. Lalanne G. Luzón J. Morales M.L. Sarsa S. Cebrián V. Kudryavtsev J. McMillan J. Lewin B. Camanzi E. Tziaferi WP2- Background simulations L. Pandola R. Santorelli L. Grandi N. Ferrari P. Loaiza G. Gerbier M. De Jesus F. Piquemal S. Cebrián G. Luzon J.M. Carmona V. Kudryavtsev J. Davies B. Camanzi C. Bungau WP3- Low background facilities M. Laubenstein N. Ferrari C. Tomei M. Balata S. Shoenert H. Simgen W. Plastino J.L. Reyss Ph. Hubert D. Lalanne J. Morales J.A. Villar J. Amare M.L. Sarsa J.M. Carmona S. Paling R. Luscher N. Smith C. Bungau J. McMillan WP4- Radiopurity of the materials A. Ianni B. Caccianiga M. Laubenstein C. Tomei J. Kisiel P. Loaiza C. Goldbach P. Hubert R Gurriaran C. Marquet J. Puimedón M.L. Sarsa J.M. Carmona S. Paling J. McMillan J. Lewin B. Camanzi

5. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 5 Meetings 1st General Meeting: September 10, 2004 (Edinburgh) Set-up of Working Groups Set-up of Working Groups Presentation of JRA1 main web page Presentation of JRA1 main web page Special session on WP2: Monte Carlo simulation codes Special session on WP2: Monte Carlo simulation codes 2nd General Meeting: January 12, 2005 (Modane) Presentation of the mid-term report Presentation of the mid-term report Coordinators: status of activities and future projects Coordinators: status of activities and future projects

6. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 6 JRA1 main web page It contains: A description of the JRA1 activity and general documents A description of the JRA1 activity and general documents News and deadlines News and deadlines JRA1 list of participants JRA1 list of participants Information on next and previous meetings Information on next and previous meetings Links to other ILIAS activities closely related to JRA1 Links to other ILIAS activities closely related to JRA1 Working group pages: participants, documents, databases, reference papers, activities… (under construction) Working group pages: participants, documents, databases, reference papers, activities… (under construction) http://www.unizar.es/ilias

7. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 7

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11. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 11 WP1 key objective: To measure the environmental background components in the four underground sites in a coherent and coordinated way. The background components in the deep underground sites 1.Environmental gamma rays 2.Radioactivity of rock, concrete, etc. 3.Neutrons 4.Rn monitoring in the air and in the water 5.Muons

12. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 12 WP1 – Environmental gamma ray background LNGS: measured with NaI, Ge, and BGO detectors LSM:measured with a portable Ge detector Boulby: planning of Ge gamma survey with a TARI project LSC: measured in old lab; plans (HPGe, NaI) for new lab Gamma from nat. radioactivity n captures (?) Data especially interesting at E>4 MeV (high energy gammas) Energy (keV) Rate (cps/keV)

13. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 13 WP1 – Environmental gamma ray background Next steps: - Coordination for new background measurements in the labs will be discussed in the next JRA1 General Meeting (June 2005) - Data interpretation: perform MC simulations use data from different detectors This will allow us to: Extract absolute emitted gamma ray fluxes Extract absolute emitted gamma ray fluxes Check the validity of the MC codes Check the validity of the MC codes Check the compatibility of the radioactivity of rock and concrete with the observed background Check the compatibility of the radioactivity of rock and concrete with the observed background Data especially interesting at E>4 MeV (high energy gammas)

14. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 14 WP1 – Radiopurity of rock & concrete in the labs Existing information collected: - Data of U, Th and K contaminations in rock and concrete collected from the labs - This information will be offered at WP1 web page, linked from JRA1 main web page Data especially interesting at E>4 MeV (high energy gammas) New project at LNGS (starting next spring): Study of the radioactivity in the rock of the Gran Sasso massive Collab. with geophysicists, partially supported by ILIAS

15. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 15 WP1 – Neutron monitoring Existing information collected: LNGS: 0.8 10 -6 n cm -2 s -1 LSM: 1.6 10 -6 n cm -2 s -1 LSC: 3.8 10 -6 n cm -2 s -1 (inferred from IGEX experiment) Boulby: 1.3 10 -6 n cm -2 s -1 (indirect measurement; new measurement under way) Data especially interesting at E>4 MeV (high energy gammas) However: -Different measurements differ in the shape of the fast neutron spectrum (LNGS) - Original number in LSM had to be revised (corrections to MC) NEW MEASUREMENTS ARE IMPORTANT

16. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 16 WP1 – Neutron monitoring Data especially interesting at E>4 MeV (high energy gammas) - Two liquid scintillator cells at LNGS will be installed nextly - 3He liquid scintillator detector used in the past at Baksan and Finland (offer from INR) - New measurements at LSM and at LSC (when new lab is finished) are also being planned Plans for new measurements: - Gd loaded scintillator detector started in Nov 04 at Boulby

17. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 17 WP1 – Radon measurements Data especially interesting at E>4 MeV (high energy gammas) LNGS:continuously monitored; 50-150 Bq/m3 in ventilated areas Boulby: ~ 5 Bq/m3; new measurements planned in 2005 LSM: new system of radon purification by adsorption in charcoal Vol. clean air : 150 m 3 /h Activity 222 Rn = 15 mBq/m 3

18. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 18 WP1 – Radon measurements LSC:30-150 Bq/m3 in old laboratory; under active control & monitorization in the new lab Data especially interesting at E>4 MeV (high energy gammas) Preliminary measurements at the excavation, without ventilation: ~ 70 Bq/m3

19. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 19 WP1 – Muon measurements Data especially interesting at E>4 MeV (high energy gammas) Existing information collected: LNGS: 1.1  m -2 h -1 (measured by MACRO, incl. angular distrib.) LSM: 0.17  m -2 h -1 LSC: 7.2  m -2 h -1 (will be also measured in the new lab) Boulby: 1.5  m -2 h -1 (recently measured by ZEPLIN) Muon

20. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 20 WP2 key objective: To produce a reliable Monte Carlo library of simulation codes for the interpretation of data and for planning future experiments. N3-BSNS JRA2(IDEA) WP3-B1 JRA1-WP2 BackgroundSimulation,Neutron-Shield and Muon-Vetos and Muon-Vetos Study on Cosmogenic Induced Activity Induced Activity

21. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 21 WP2 – Activities Main initial activity: existing codes compared and discussed Gamma background: GEANT4 Neutrons: SOURCES (production) FLUKA, MCNP, GEANT4 (propagation) Muon-induced neutrons:MUSIC, MUSUN, SIAM, FLUKA (prod.) FLUKA, GEANT4 (propagation) Tasks: - Compare simulation vs experimental data - Compare one code vs another code Data especially interesting at E>4 MeV (high energy gammas)

22. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 22 WP2 – Neutron production SOURCES: - Neutron flux and energy spectrum from U/Th contaminations - Problem: no alphas above 6.5 MeV → modifications of the code - Major problem: neutron energy spectrum in the laboratory (after propagation) is softer than the one measured Data especially interesting at E>4 MeV (high energy gammas) Production spectrum from mod. SOURCES Spectrum propagated with GEANT4 Evaluated spectrum from measurements (Modane) Carson et al. Astropart. Phys. 21 (2004) 667

23. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 23 WP2 – Neutron production SOURCES: - Energy spectra of alphas incident on Al and Mg slabs are however in good agreement with experimental data Data especially interesting at E>4 MeV (high energy gammas) 5.0 MeV alphas - Al 2 O 3 5.5 MeV alphas - Mg (natural) Are cross-sections, transition probabilities and other features correct? The code was tested against measured spectra from various sources, but need more accurate measurements in underground labs (including neutron spectra). Jacobs and Liskien, Annals of Nuclear Energy, 10 (1983) 541

24. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 24 WP2 – Neutron propagation and detection MCNP and GEANT4: Substantial differences, probably (partly) due to the difference in initial neutron spectra and geometry. Data especially interesting at E>4 MeV (high energy gammas) Wulandari et al. Talk at IDM2004Carson et al. Astropart. Phys. 21 (2004) 667 MCNP 10 4 suppression with 50 cm PE GEANT4 > 10 5 suppression after 50 g/cm 2 PE

25. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 25 WP2 – Neutron propagation and detection MCNP and GEANT4: Substantial differences, probably (partly) due to the difference in initial neutron spectra and geometry. Data especially interesting at E>4 MeV (high energy gammas) Neutron propagation through the shielding with the two codes is needed using the same geometry and the same input neutron spectrum – work in progress

26. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 26 WP2 – Muon-induced neutrons FLUKA and GEANT4: - Comparison: yield, spectrum, lateral distribution, and dependence with material. - Both codes agree within a factor of 2 (or even better). Data especially interesting at E>4 MeV (high energy gammas) GEANT4: Araujo et al., hep-ex/0411026 FLUKA: Kudryavtsev et al. NIMA, 505 (2003) 688 However, there is systematic higher production with FLUKA in most materials

27. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 27 WP2 – Activities Comparison of codes with experiments: - 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). Data especially interesting at E>4 MeV (high energy gammas)

28. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 28 WP2 – Activities First ‘test’ version of the MC libraries: - It will be ready in February 2005 - It will include: General information about codes and links to the code web-site General information about codes and links to the code web-site Modifications to codes Modifications to codes Library of examples used by underground groups Library of examples used by underground groups - A mailing distribution list has been created to optimize exchange of ideas (info: http://webmail.unizar.es/mailman/listinfo/montecarlo) - An FTP repository for codes with access through main JRA1 web page has been created (info: luzon@unizar.es) Data especially interesting at E>4 MeV (high energy gammas)

29. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 29 WP3 key objectives: Construction and upgrading of ultra low background facilities (ULBF) in the four underground labs forming an EU-coordinated service for applications in rare event physics and other fields of world-wide value. Implementation of new techniques to deal with the background: active and passive shielding, veto systems, particle discrimination techniques, fragmentation of calorimeter detectors, control and suppression of radon levels... Study of the feasibility of fabrication of detectors and materials underground.

30. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 30 WP3 – Low background facilities: LNGS Data especially interesting at E>4 MeV (high energy gammas) Strengthening of the ultra low-level background facilities at LNGS: Extension of the Low Level Laboratory at LNGS  Extension of the Low Level Laboratory at LNGS  New generation of HP-Ge detectors for ultra low-level applications  Set-up of ultra low-level scintillation counter systems  Ultra low-level gas counting (GNO counting lab) GNO Ultra low-level gas counting Ultra low-level HPGe detector @ LNGS

31. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 31 WP3 – Low background facilities: Boulby Data especially interesting at E>4 MeV (high energy gammas) New ULBF laboratory at Boulby: 7.68m 0.8m 4.28m 11.96m 6.0m Small Proj Bay GE 1 GE 2 GE 3 GE 4 Desk Storage Desk Storage Entrance Clean-Off 6.0m Plan for JIF Low Background Lab (Stub A) 0.5T swing crane (in place) AC unit Plans to develop the existing Ge facility in the new ULB laboratory

32. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 32 WP3 – Low background facilities: LSM Data especially interesting at E>4 MeV (high energy gammas) On going-projects: Improvement of a low-background Ge detector, IRIS (400 cc) Improvement of a low-background Ge detector, IRIS (400 cc) A new planar Ge detector will be acquired A new planar Ge detector will be acquired The Rn trapping facility was recently installed The Rn trapping facility was recently installed Construction of a Radon precision measuring facility, with a sensitivity of ~ mBq/m3 (Vol. 70 l) Construction of a Radon precision measuring facility, with a sensitivity of ~ mBq/m3 (Vol. 70 l)

33. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 33 WP3 – Low background facilities: LSC Data especially interesting at E>4 MeV (high energy gammas) New laboratory: two new ULB 2 kg Ge detectors (one of them already acquired) for material testing will be installed in the new LSC Old laboratory: 1 kg Ge prototypedetector, equipped with an overpressure system of gaseous N 2 to minimize Rn intrusion Old laboratory: 1 kg Ge prototype detector, equipped with an overpressure system of gaseous N 2 to minimize Rn intrusion

34. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 34 WP4 key objectives: Collect new (and old) data on radioactive contamination and cosmogenic activation of materials used in rare-event physics experiments and ultra-low background instrumentation - Collect new (and old) data on radioactive contamination and cosmogenic activation of materials used in rare-event physics experiments and ultra-low background instrumentation - Development and test of purification techniques to improve the radio-purity of materials.

35. ILIAS 2nd Annual meeting. Prague. February 2005 JRA1 web page http://www.unizar.es/ilias 35 WP4 – Activities Data especially interesting at E>4 MeV (high energy gammas) Ellaboration of a database on radiopurity of materials: The database is stored in a dedicated server of the Centre de Calcul de Lyon. It is built using MySQL system combined with php scripts which allow to communicate from the web page to the database. The database is stored in a dedicated server of the Centre de Calcul de Lyon. It is built using MySQL system combined with php scripts which allow to communicate from the web page to the database. Data has been collected from LSC (ANAIS, CAST & ROSEBUD), LSM (EDELWEISS), from the UKDM site and from publications. At LRT2004, SNO people proposed to make their measurements available to be included in the database.At LRT2004, SNO people proposed to make their measurements available to be included in the database. Systematic comparison of measurements in the different labs: Cross-check with one or more reference samples to compare instrumentation and possible systematic in the analysis method is under discussion