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Nakashima, Hiroshi; Mokhov, N.*; 28 of others*
Progress in Nuclear Science and Technology (Internet), 4, p.191 - 196, 2014/04
In JASMIN, a series of experiments has been performed with the intense 120-GeV proton beams at Fermilab. The secondary particles created in such interactions were measured around the targets as well as in their penetration through steel, concrete and rock. Nuclear data such as activation and mass distributions of residual nuclei have been measured by activation methods. Double differential neutron production yield has also been measured by a time of flight techniques. Comparison of results calculated by PHITS and MARS reveals in general a good agreement. Further analyses are in progress.
Sanami, Toshiya*; Iwamoto, Yosuke; Shigyo, Nobuhiro*; Hagiwara, Masayuki*; Lee, H.-S.*; Leveling, A.*; Vaziri, K.*; Boehnlein, D.*; Mokhov, N.*; Sakamoto, Yukio; et al.
Progress in Nuclear Science and Technology (Internet), 1, p.44 - 47, 2011/02
Muons become important particle for radiation safety design of high energy and intense accelerator since muons penetrate a thick shielding wall. In this study, the dose rate distributions around high intensity muon beam were measured at the muon alcoves and the bypass tunnel of Neutrinos at the Main Injector (NuMI) facility in Fermi National Accelerator Laboratory (Fermilab). The dosimeters of Luxel budges (OSL, CR39) and TLD budges (UD813PQ) were placed in the second, third and forth alcoves to measure muons, photons, and, thermal and fast neutrons. Neutrons and photons were measured in the bypass tunnel using a Bonner sphere and an ionization chamber. The spatial distribution of muons is calculated using MARS code. The results of dosimeters show same spatial distribution including attenuation along the beam line in comparison with the calculation results.
Yashima, Hiroshi*; Kasugai, Yoshimi; Matsuda, Norihiro; Matsumura, Hiroshi*; Iwase, Hiroshi*; Kinoshita, Norikazu*; Mokhov, N.*; Leveling, A.*; Boehnlein, D.*; Vaziri, K.*; et al.
Progress in Nuclear Science and Technology (Internet), 1, p.48 - 51, 2011/02
The shielding experiment was performed at the anti-proton production target station in Fermi National Accelerator Laboratory. Aluminum, Bismath, Niobium, Copper and Indium samples were placed behind the shields. After irradiation, induced activities of samples were measured by using HPGe detector. The spatial distribution of reaction rate of samples which were placed behind the iron and concrete shields 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 obtained reaction rates were also fitted to Moyer's formula, and the attenuation lengths for iron and concrete shields were obtained.
Hagiwara, Masayuki*; Sanami, Toshiya*; Iwamoto, Yosuke; Arakawa, Hiroyuki*; Shigyo, Nobuhiro*; Mokhov, N.*; Leveling, A.*; Boehnlein, D.*; Vaziri, K.*; Nakamura, Takashi*; et al.
Progress in Nuclear Science and Technology (Internet), 1, p.52 - 56, 2011/02
In pbar target station, the pulsed proton beam with the power of around 75 kW and the time structure of 1.6 
s pulse width and 2.2 s cycle time bombards the pbar production target and produces high instantaneous intensity neutron (burst neutron) fields. The duration of the burst neutrons, which is less than s, is very severe condition to measure neutron spectra with a conventional Bonner sphere technique with pulse readout electronics because of signal pile-up problem. In this study, we have developed a current readout Bonner sphere technique to measure neutron spectra in a burst neutron field. We have measured the neutron spectra on the pbar target and graphite dump. The neutron spectra obtained with the present technique show generally good agreements with the calculation results using MARS code except difference of the thermal neutron flux due to the geometrical problem.
Matsuda, Norihiro; Kasugai, Yoshimi; Matsumura, Hiroshi*; Yashima, Hiroshi*; Iwase, Hiroshi*; Kinoshita, Norikazu*; Sanami, Toshiya*; Mokhov, N.*; Leveling, A.*; Boehnlein, D.*; et al.
Progress in Nuclear Science and Technology (Internet), 1, p.57 - 60, 2011/02
The anti-proton (pbar) production target in Fermi National Accelerator Laboratory can be produced a wide variety of secondary particles including of anti-protons, by bombarding with protons accelerated to 120 GeV. The shielding experimental data, which was obtained around the pbar target, make possible to validate the accuracies of the general-purpose Monte Carlo simulation codes. In this paper, spatial distribution of reaction rates were calculated with two-dimensional (r-z) geometry simplified the real pbar target station using the PHITS, MARS and MCNPX code. These experimental data in iron shield were compared with the calculated data. The comparison for attenuation length of iron were good agreement between the experiments and calculations.
Nakashima, Hiroshi
no journal, ,
Experimental studies of shielding and radiation effects at Fermi National Accelerator Laboratory (FNAL) have been carried out under collaboration between FNAL and Japan, aiming at benchmarking simulation codes and study of irradiation effects for upgrade and design of new high-energy accelerator facilities. The first campaign of the experiment was carried out at the Pbar target station and Numi experimental station at FNAL, using antiproton and neutrino production targets irradiated by 120-GeV protons. The generated secondary particles passing through steel, concrete and rock were measured by activation methods as well as by other detectors such as scintillator with a veto counter, phoswich detector and a Bonner ball counter on trial. Preliminary experimental results are presented.
Matsumura, Hiroshi*; Kasugai, Yoshimi; Yashima, Hiroshi*; Iwase, Hiroshi*; Matsuda, Norihiro; Kinoshita, Norikazu*; Sanami, Toshiya*; Hagiwara, Masayuki*; Shigyo, Nobuhiro*; Arakawa, Hiroyuki*; et al.
no journal, ,
A gold activation detector was studied as a high energy neutron detector at high radiation field in a series of shielding experiment at Fermi National Accelerator Laboratory. We could measure spallation residual nuclei with wide threshold energy by using a combination method with radiological chemical separation and X-X-
coincidence detection methods. It was shown the detector was effective for high energy neutron detector.
Kasugai, Yoshimi; Yashima, Hiroshi*; Matsuda, Norihiro; Kinoshita, Norikazu*; Matsumura, Hiroshi*; Iwase, Hiroshi*; Nakashima, Hiroshi; Sakamoto, Yukio; Hirayama, Hideo*; Ishibashi, Kenji*; et al.
no journal, ,
On the shielding experiment, started on 2007, as collaborative research with Fermilab using high energy proton accelerators, the measurement of reaction rate distributions in the antiproton target station has been carried out. Reaction rates were measured with activation method. Using the reaction rate data, neutron spectra at each measurement position were deduced by means of nonlinear least square method; a shape of the neutron spectrum between 5 and 100 MeV was expressed as a fitting function with 5 fitting parameters, whose values were determined at a minimum of 
values for the reaction rates. In the presentation, systematics of the variation of neutron spectra in the shield will be discussed.
Nakashima, Hiroshi; Mokhov, N.*; Iwamoto, Yosuke; Matsuda, Norihiro; Kasugai, Yoshimi; Sakamoto, Yukio; Leveling, A.*; Boehnlein, D.*; Vaziri, K.*; Sanami, Toshiya*; et al.
no journal, ,
Several multi-purpose high-energy radiation transport codes are used in many research fields such as high-energy physics as well as accelerator facility shielding designs. The codes are benchmarked against experimental data on a regular basis. To promote this to a higher level and to a hardly explored field of neutron radiation induced by energetic muons, a JASMIN collaboration (Japanese-American Study of Muon Interaction and Neutron detection), has been created with several Laboratories and Universities of Japan and U.S.A. The collaboration has performed a series of experiments at the Pbar target station and NuMI facility at Fermi National Accelerator Laboratory, using irradiation of targets with 120 GeV protons for antiproton and neutrino production. This paper reviews recent activities and results.
stripping to protons by using lasers at J-PARC RCSSaha, P. K.; Harada, Hiroyuki; Kinsho, Michikazu; Miura, Akihiko; Yamane, Isao*
no journal, ,
