1. 1 JASMIN Activation Experiments (T-972/993/994) Yoshimi Kasugai on behalf of JASMIN Activation team JASMIN Activation team Y. Kasugai, K. Oishi, H. Matsumura, H. Yashima, N. Matsuda, H. Iwase, A. Toyoda,

2. 2 Introduction – What’s JASMIN Shielding experiments under a collaborative project of JASMIN started on 2007 using high-energy proton accelerator at Fermilab. –JASMIN: Japanese and American Study on Muon Interaction and Neutron Detection The experiments are carrying out at –Pbar, NuMI and FTBF. JASIM has two experimental groups: –Counter Team  Dec., 6’ s Talk by Sanami –Activation Team Results of the Activation team will be presented now.

3. 3 Motivation and Experiment Analysis of secondary particles (neutrons and muons) on in-shield behavior for high-energy proton accelerators (E p > 100 GeV) => Validation of high-energy particle transportation codes => Discovery of a macroscopic principle of particle behavior => Radiation safety Chemical behavior of radioactive products Pbar –Neutron flux distribution and the attenuation in steel and concreted shield –Analysis of air gas and cooling water in the radiation environment. NuMI –Muon-induced nuclide production –Muon attenuation in rock Fermilab Test Beam Facility (FTBF): –Elemental study on the radioactivity production and the chemical behavior

4. 4 Pbar

5. 5 Shielding Experiment at Pbar Multi-foil Activation Method  Position: In-steel & Shield surface  Foils: In, Al, Nb, Bi => Coverage of Neutrons between1 MeV and 100 MeV

6. 6 Comparison of neutron spectra between Expr. and Calc. The neutron attenuation length for iron shield was obtained: 150±5 g/cm 2. The shapes of neutron spectra by PHITS calculation was not so bad in comparison with the experiments. The experimental data of neutron attenuation in concrete shield are required for further analysis.  The experiments will be carried out in this series. In Steel On Steel On Concrete Target Outer The neutron spectra along the line from the inner to outer.

7. 7 Measurement of Radioactive Aerosol in High-energy Proton Target Station at Fermilab. Target room 120 GeV proton target Existing gas- sampling system Impactor flow meter Pump Concrete shielding Iron shielding Sampling from target room using Impactor (2/15, 10:20- 3h sampling)

8. 8 After sampling using Impactor ・・・  -ray spectrometry of radioactive aerosols collected on aluminum foil which are equipped in each stage (10 stages in total) of the impactor Be-7, Na-24, Sc-46, Sc-47, V-48, Cr-51, Mn-52, Mn-54, Co-56, Co-57, Co-58, Ni-57, Au-196, Au-198 from target room Be-7 53.3 d The experimental data indicate that: → Particle size distribution of radionuclides show “aerosol growth” in the accelerator target room →We can estimate the velocity of particle growth using half-life of each nuclide.

9. 9 NuMI

10. 10 Nuclear reactions in NuMI beam line Variation of activity High! Theoretical Experimental Muon Attenuation Nuclide Production Large gaps are seen in Alcove-1.

11. 11 Measurement of the Original Beam 190 sets of samples were place on the front surface of the Hadron absorber.

12. 12 We found two large peaks at the absorber 40 cm What are these large peaks??? 120 cm Distribution of Au-196 activity

13. 13 FTBF

14. 14 120GeV p monitor foil(Al) irradiation samples SEM Nuclide Production induced by 120 GeV-protons Cross Section data of nuclide production for 120- GeV proton bombardment

15. 15 Radiocolloid formation study by proton irradiation Irradiation to Cu Cu Fe Be-7 Ion-to-Colloid ratios for each radioactive products were measured. Important data for handling the cooling water in the radiation environment from the radiation-safety point of view

16. 16 Summary Experimental data on neutron behavior have been obtained in the view points of attenuation of steel shield. –Experiments on concrete-attenuation will be done in this series. Experimental data of muon attenuation and muon-induced nuclide production data has been obtained. –Still remains the spitted beam issue at the Hadron-absorber surface. => Now we are investigating. Chemical behaviors of radionuclide produced in air gas and cooling water has been investigated. Thanks to Fermilab T972/T993/T994 members, N.Mokhov, A.Leveling, D. Boehnlein, K.Vaziri Pbar / NuMI / Rad. safety stuffs FTBF members, A.Soha, E.Ramberg, R.Coleman, D.Jensen