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The production cross sections of 10Be and 26Al were measured by accelerator mass spectrometry using 89Y, 159Tb, and natCu targets bombarded by protons with energies Ep of 120 GeV and 392 MeV. The production cross sections obtained for 10Be and 26Al were compared with those previously reported using Ep = 50 MeV–24 GeV and various targets. It was found that the production cross sections of 10Be monotonically increased with increasing target mass number when the proton energy was greater than a few GeV. On the other hand, it was also found that the production cross sections of 10Be decreased as the target mass number increased from that of carbon to those near the mass numbers of nickel and zinc when the proton energy was below approximately 1 GeV. They also increased as the target mass number increased from near those of nickel and zinc to that of bismuth, in the same proton energy range. Similar results were observed in the production cross sections of 26Al, though the absolute values were quite different between 10Be and 26Al. The difference between these production cross sections may depend on the impact parameter (nuclear radius) and/or the target nucleus stiffness.

The energy spectra of neutrons were measured by a time-of-flight method for 120 GeV protons on thick graphite, aluminum, copper, and tungsten targets with an NE213 scintillator at the Fermilab Test Beam Facility. Neutron energy spectra were obtained between 25 and 3000 MeV at emission angles of 30°, 45°, 120°, and 150°. The spectra were parameterized as neutron emissions from three moving sources and then compared with theoretical spectra calculated by PHITS and FLUKA codes. The yields of the theoretical spectra were substantially underestimated compared with the yields of measured spectra. The integrated neutron yields from 25 to 3000 MeV calculated with PHITS code were 16–36% of the experimental yields and those calculated with FLUKA code were 26–57% of the experimental yields for all targets and emission angles.

Akihiro Toyoda, Hiroshi Matsumura, Kazuyoshi Masumoto, Shun Sekimoto, Hiroshi Yashima, Norihiro Matsuda, Yoshimi Kasugai, Yukio Sakamoto, Hiroshi Nakashima, Gary Lauten, Anthony Leveling, Nikolai Mokhov, Kamran Vaziri, Koji Oishi, Makoto Kuroyanagi, Fumiyoshi Nobuhara and Katsuhiko Takahashi High Energy Accelerator Research Organization, 1-1 Oho Tsukuba, Ibaraki 305-0801, Japan; Kyoto University Research Reactor Institute, 2 Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan; Japan Atomic Energy Agency, 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki, 319-1195, Japan; Fermi National Accelerator Laboratory, Batavia, IL 60510-5011, USA; Shimizu Corporation, 3-4-17 Etchujima, Koto-ku, Tokyo 135-8530, Japan; Tokyo Nuclear Services, 1-3-5 Taito, Taito-ku, Tokyo 110-0016, Japan; Dokkyo Medical University, 880 Kitakobayashi, Mibu-machi, Shimotsuga-gun, Tochigi 321-0293, Japan

Norihiro Matsuda, Yoshimi Kasugai, Hiroshi Matsumura, Hiroshi Iwase, Akihiro Toyoda, Hiroshi Yashima, Shun Sekimoto, Koji Oishi, Yukio Sakamoto, Hiroshi Nakashima, Takashi Nakamura, David Boehnlein, Gary Lauten, Anthony Leveling, Nikolai Mokhov and Kamran Vaziri Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai-mura, Naka-gun, Ibaraki, 319-1195, Japan; High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan; Kyoto University Research Reactor Institute, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan; Shimizu Corporation, 4-17, Etchujima 3-chome, Koto-ku, Tokyo, 135-8530, Japan; ATOX Co. Ltd, Technical Development Center, 1201 Takada, Kashiwa, Chiba, 277-0861, Japan; Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8578, Japan; Fermi National Accelerator Laboratory, Batavia, IL, 60510, USA

In order to investigate the accuracy of high-energy radiation transport codes based on experimental data, the collaboration; Japanese and American Study of Muon Interaction and Neutron detection (JASMIN), has been formed among many institutions and universities of Japan and U.S.A. A series of experiments have been conducted at the Fermilab Pbar target station, the NuMI beam line and the Fermilab Test Beam Facility (FTBF). In this paper the research activities are reviewed.

Systematics of neutron energy spectra for 120 GeV protons on C, Al, Cu and W targets are presented for data measured using the time-of-flight technique, room-scattering subtraction, and experimentally determined neutron detection efficiency. The measured neutron energy spectra exhibited low-energy angular-independent and high-energy angular-dependent components, below and above about 50 MeV, respectively. The neutron yields of both components increased linearly with target thickness. We obtained neutron yields for one interaction length target and determine the normalization factors from the ratio of the target thickness to the interaction length. We observed a non-linear relationship between neutron yield and target mass number.

The FermiCORD code system, a set of codes based on MARS15 that calculates the accelerator-induced residual doses at experimental facilities of arbitrary configurations, has been developed. FermiCORD is written in C++ as an add-on to Fortran-based MARS15. The FermiCORD algorithm consists of two stages: 1) simulation of residual doses on contact with the surfaces surrounding the studied location and of radionuclide inventories in the structures surrounding those locations using MARS15, and 2) simulation of the emission of the nuclear decay $\gamma$-quanta by the residuals in the activated structures and scoring the prompt doses of these $\gamma$-quanta at arbitrary distances from those structures. The FermiCORD code system has been benchmarked against similar algorithms based on other code systems and against experimental data from the CERF facility at CERN, and FermiCORD showed reasonable agreement with these. The code system has been applied for calculation of the residual dose of the target station for the Mu2e experiment and the results have been compared to approximate dosimetric approaches., Comment: Replaced with published version. Available under Creative Commons License CC-BY-NC-ND 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

A methodology for the time-of-flight measurement of the neutron energy spectrum for a high-energy proton-beam-induced reaction was established at the Fermilab Test Beam Facility of the Fermi National Accelerator Laboratory. The 120-GeV proton beam with 3 × 10 5 protons/spill was prepared for event-by-event counting of incident protons and emitted neutrons for time-of-flight energy determination. An NE213 organic liquid scintillator (12.7 cm in diameter by 12.7 cm in length) was employed with a veto plastic scintillator and a pulse-shape discrimination technique to identify neutrons. Raw waveforms of NE213, veto and beam detectors were recorded to discriminate the effects of multi-proton beam events by considering different time windows. The neutron energy spectrum ranging from 10 to 800 MeV was obtained for a 60-cm-long copper target at 90° with respect to the beam axis. The obtained spectrum was consistent with that deduced employing the conventional unfolding technique as well as that obtained in a 40-GeV/c thin-target experiment.

The JASMIN Collaboration has performed an experiment to conduct measurements of nuclear reaction rates around the anti-proton production (Pbar) target at the Fermi National Accelerator Laboratory (FNAL). At the Pbar target station, the target, consisting an Inconel 600 cylinder, was irradiated by a 120 GeV/c proton beam from the FNAL Main Injector. The beam intensity was 3.6 x 10**12 protons per second. Samples of Al, Nb, Cu, and Au were placed near the target to investigate the spatial and energy distribution of secondary particles emitted from it. After irradiation, the induced activities of the samples were measured by studying their gamma ray spectra using HPGe detectors. The production rates of 30 nuclides induced in Al, Nb, Cu, Au samples were obtained. These rates increase for samples placed in a forward (small angle) position relative to the target. The angular dependence of these reaction rates becomes larger for increasing threshold energy. These experimental results are compared with Monte Carlo calculations. The calculated results generally agree with the experimental results to within a factor of 2 to 3., 6 pp. ND 2010: International Conference on Nuclear Data for Science and Technology, 26-30 Apr 2010: Jeju Island, Korea

In an antiproton production (Pbar) target station of the Fermi National Accelerator Laboratory (FNAL), the secondary particles produced by bombarding a target with 120-GeV protons are shielded by a thick iron shield. In order to obtain experimental data on high-energy neutron transport at more than 100-GeV-proton accelerator facilities, we indirectly measured more than 100-MeV neutrons at the outside of the iron shield at an angle of 50° in the Pbar target station. The measurement was performed by using the Au activation method coupled with a low-background γ-ray counting system. As an indicator for the neutron flux, we determined the production rates of 8 spallation nuclides ( 196 Au, 188 Pt, 189 Ir, 185 Os, 175 Hf, 173 Lu, 171 Lu, and 169 Yb) in the Au activation detector. The measured production rates were compared with the theoretical production rates calculated using PHITS. We proved that the Au activation method can serve as a powerful tool for indirect measurements of more than100-MeV neutrons that play a vital role in neutron transport. These results will be important for clarifying the problems in theoretical calculations of high-energy neutron transport. Work supported by a Grant-in-Aid from the Ministry of Education (KAKENHI 19360432 and 20354764), Japan and by Fermi Research Alliance, LLC under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy. Published in Journal of the Korean Physical Society. Corresponding author. E-mail : hiroshi.matsumura@kek.jp

JASMIN - Japanese and American Study of Muon Interaction and Neutron detection - a program for studies of shielding and irradiation effect around high energy accelerators has been started until 2007 using high energy proton accelerators located in Fermi National Accelerator Laboratory (FNAL) as a collaboration of JAPAN and FNAL. The series of the presentations entitled "Shielding experiments at high energy accelerators of Fermilab" describes the part of the results of this collaboration regarding transport of secondary particles, neutron and muon, from 120 GeV proton induced reactions through experimental data and simulation. In this study, the spatial distribution of reaction rate of activation samples which were placed on pbar anti proton target station were obtained. The measured data shows that the reaction rates on the outer surfaces of the iron and concrete shields increases toward the downstream of the target. The attenuation length for iron were obtained from depth distribution of reaction rates in iron shield. The obtained reaction rates were also fitted to Moyer's formula. The shape of angular distribution of fitted reaction rates agree with that of measured reaction rates for �� = 60 - 120 degrees.

JASMIN - Japanese and American Study of Muon Interaction and Neutron detection - a program for studies of shielding and irradiation effect around high energy accelerators has been started since 2007 using high energy proton accelerators located in Fermi National Accelerator Laboratory (FNAL) as a collaboration of JAPAN and FNAL. The series of the presentations entitled "Shielding experiments at high energy accelerators of Fermilab" describes the part of the results of this collaboration regarding transport of secondary particles, neutron and muon, from 120 GeV proton induced reactions through experimental data and simulation. In this paper, behavior and associated radiation dose of high energy muons in tens of meter thick rock are measured using OSLs, CR39s, TLDs and an ionization chamber. The doses for the same geometrical condition of the experiment are calculated using multi-particle Monte Carlo simulation code, MARS, to check its predictive power for muon transport and the dose. From this comparison, consistency between the experiment and calculation is confirmed in 60 m thick rock. The calculation enables to separate contributions of each particle to the dose. The result shows considerable amount of the contribution to the dose from electrons, photons and neutrons from electro-magnetic cascade due to interaction of high energy muon.

JASMIN - Japanese and American Study of Muon Interaction and Neutron detection - a program for studies of shielding and irradiation effect around high energy accelerators has been started until 2007 using high energy proton accelerators located in Fermi National Accelerator Laboratory (FNAL) as a collaboration of JAPAN and FNAL. The series of the presentations entitled "Shielding experiments at high energy accelerators of Fermilab" describes the part of the results of this collaboration regarding transport of secondary particles, neutron and muon, from 120 GeV proton induced reactions through experimental data and simulation. In this paper, calculation analyses using high energy particle transport Monte Carlo calculation codes, PHITS, MARS and MCNPX, for the experiments carried out at the anti-proton production target station were performed with a simplified two-dimensional geometry to validate the accuracy of spatial distribution of reaction rate in iron shield and the attenuation length. The calculation results were good agreement with the obtained experimental data for the spatial distribution. Neutron attenuation lengths of iron were also given by the data. Tendencies of the attenuation length of iron were found the PHITS and MARS values were larger and the MCNPX values were smaller than the data.

High Energy Accelerator Research Organization, 1-1, Oho, Tsukuba, Ibaraki 305-0801, Japan Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195, Japan Kyushu University, 744, Motooka, Nishi-ku, Fukuoka 819-0395, Japan Fermilab, Batavia, IL 60510-5011, USA Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan Shimizu Corporation, 4-17, Etchujima, 3-chome, Koto-ku, Tokyo 135-8530, Japan

In our previous study, double and mirror symmetric activation peaks found for Al and Au arranged spatially on the back of the Hadron absorber of the NuMI beamline in Fermilab were considerably higher than those expected purely from muon-induced reactions. From material activation bench-mark experiments, we conclude that this activation is due to hadrons with energy greater than 3 GeV that had passed downstream through small gaps in the hadron absorber.

Experimental studies of shielding and radiation effects are carried out at Fermi National Accelerator Laboratory (FNAL) under collaboration between FNAL and Japan, aiming at benchmarking simulation codes and studying irradiation effects for the upgrade and design of new high-energy accelerator facilities. The purposes of this collaboration are (a) acquisition of shielding data in a proton beam energy region above 100 GeV, (b)further evaluation of predictive accuracy of the PHITS and MARS codes, (c) modification of physics models and data in these codes if needed, (d) characterization of radiation fields for studies of radiation effects, and (e) development of a code module for an improved description of radiation effects. The first campaign of the experiment was carried out at the Pbar target station and NuMI experimental station at FNAL, which use irradiation of targets with 120-GeV protons for antiproton and neutrino production, respectively. The generated secondary particles passing through steel, concrete, and rock were measured by activation methods as well as by other detectors such as a scintillator with a veto counter, phoswich detector, and a Bonner ball counter on trial. Preliminary experimental and calculated results are presented.

An extraction beamline and an experimental area have been designed for the Fermilab Linac. The design exploits attributes of the Linac in order to adapt it to a wide range of applications and purposes. Charge stripping of H/sup -/ ions enables beam manipulations which contribute enormously to the capabilities and flexibility of the facility. The proposed Linac Experimental Area would provide facilities for research and development in accelerator physics, medical physics, health physics, and atomic physics.

The Japanese and American Study of Muon Interaction and Neutron detection (JASMIN) collaboration, has been conducting shielding experiments using the Fermilab anti-proton target station (Pbar) shielding assembly. A multi-foil technique was used to measure the high energy neutron spectra, in the range of 1 to 100 MeV, for the target station shielding configuration. The neutron spectra were de-convoluted using a new fitting method. This method is based on the assumption that a neutron spectrum can be expressed as a simple sum of two exponentials. The validity of the fitting method was confirmed by comparison with the results obtained using SAND-II computer code and theoretical calculations. Finally, it was found that there are simple correlations between reaction rates and the adjustable parameters in the fitting function.