Activation detector measurements at the hadron absorber of the NuMI neutrino beamline at Fermilab

Matsuda, Norihiro; Kasugai, Yoshimi; Matsumura, Hiroshi*; Iwase, Hiroshi*; Toyoda, Akihiro*; Yashima, Hiroshi*; Sekimoto, Shun*; Oishi, Koji*; Sakamoto, Yukio*; Nakashima, Hiroshi; et al.

Progress in Nuclear Science and Technology (Internet), 4, p.337 - 340, 2014/04

https://doi.org/10.15669/pnst.4.337

The Neutrinos at the Main Injector (NuMI) at Fermilab produces intense neutrino beam to investigate the phenomena of the neutrino mixing and oscillation. The Hadron Absorber, consists of thick blocks of aluminum, iron and concrete, is placed at the end of decay volume as a dump for primary proton and secondary particles generated in NuMI. In order to estimate the shielding effect, the reaction rate measurements with activation detector were carried out on the back surface of the absorber. The induced activities in the detectors were measured by analyzing their -ray spectra using HPGe detectors. Two kind of peak was showed on two-dimensional distributions of obtained reaction rates at right angle to the beam direction. One was strong peaks at the both horizontal side. And, another smaller was at the top. It was concluded that these peaks were the results of particles streaming through the gaps in the Hadron Absorber shielding.

Shielding experiments under JASMIN collaboration at Fermilab, 4; Measurement and analyses of high-energy neutron spectra in the anti-proton target station

Matsuda, Norihiro; Kasugai, Yoshimi; Sakamoto, Yukio; Nakashima, Hiroshi; Matsumura, Hiroshi*; Iwase, Hiroshi*; Kinoshita, Norikazu*; Hirayama, Hideo*; Yashima, Hiroshi*; Mokhov, N.*; et al.

Journal of the Korean Physical Society, 59(2), p.2055 - 2058, 2011/08

https://doi.org/10.3938/jkps.59.2055

It is important to obtain neutron spectra and its intensity on shielding experiment. Deduction of high-energy neutron spectra were done using fitting and unfolding methods based on the shielding data obtained at the anti-proton (pbar) target station in Fermilab. The neutron spectra for fitting method is useful to be easily obtained and the values gave reasonable results compared with nuclear data. Therefore, that for unfolding methods included inconsistency. Furthermore, the deduced neutron spectra were verified through the calculation analyses by PHITS code.

Shielding experiments under JASMIN collaboration at Fermilab, 3; Measurement of high-energy neutrons penetrating a thick iron shield from the antiproton production target by Au activation method

Matsumura, Hiroshi*; Kinoshita, Norikazu*; Iwase, Hiroshi*; Toyoda, Akihiro*; Kasugai, Yoshimi; Matsuda, Norihiro; Sakamoto, Yukio; Nakashima, Hiroshi; Yashima, Hiroshi*; Mokhov, N.*; et al.

Journal of the Korean Physical Society, 59(2), p.2059 - 2062, 2011/08

https://doi.org/10.3938/jkps.59.2059

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 proton accelerator facilities, we indirectly measured 100-MeV neutrons at the outside of the iron shield. The measurement was performed by using the Au activation method coupled with a low-background -ray counting system. As an indicator for the neutron flux, we determined the production rates of 8 spallation nuclides (Au, Pt, Ir, Os, Hf, Lu, Lu, and 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 100-MeV neutrons that play a vital role in neutron transport.

Shielding experiments at high energy accelerators of Fermilab, 3; Neutron spectrum measurements in intense pulsed neutron fields of the 120-GeV proton facility using a current Bonner sphere technique

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

https://doi.org/10.15669/pnst.1.52

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.

Thick target neutron yield at 0 degree by 250 and 350 MeV protons

Iwamoto, Yosuke; Taniguchi, Shingo*; Nakao, Noriaki*; Itoga, Toshio*; Nakamura, Takashi*; Nakane, Yoshihiro; Nakashima, Hiroshi; Satoh, Daiki; Yashima, Hiroshi*; Yamakawa, Hiroshi*; et al.

Proceedings of 8th Specialists' Meeting on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF-8), p.195 - 203, 2010/03

Neutron energy spectra at 0 degree produced from stopping-length thick graphite, aluminum, iron and lead targets bombarded by 250 MeV and 350 MeV protons were measured at the neutron TOF course at RCNP of Osaka University. The neutron energy spectra were obtained by using the time-of-flight technique in the energy range from 10 MeV to incident proton energy. To compare the experimental results, Monte Carlo calculations by the PHITS and MCNPX codes using the JENDL-HE and the LA150 evaluated nuclear data files were performed. It was found that these calculated results at 0-degree generally underestimated the experimental results for all targets in the energy range above 20 MeV.

Measurement of thick target neutron yields at 0 bombarded with 140, 250 and 350 MeV protons

Iwamoto, Yosuke; Taniguchi, Shingo*; Nakao, Noriaki*; Itoga, Toshio*; Yashima, Hiroshi*; Nakamura, Takashi*; Satoh, Daiki; Nakane, Yoshihiro; Nakashima, Hiroshi; Kirihara, Yoichi*; et al.

Nuclear Instruments and Methods in Physics Research A, 593(3), p.298 - 306, 2008/08

https://doi.org/10.1016/j.nima.2008.05.013

Neutron energy spectra at 0 produced from stopping-length graphite, aluminum, iron and lead targets bombarded with 140, 250 and 350 MeV protons were measured at the neutron TOF course in RCNP of Osaka University. The neutron energy spectra were obtained by using the time-of-flight technique in the energy range from 10 MeV to incident proton energy. To compare the experimental results, Monte Carlo calculations with the PHITS and MCNPX codes were performed using the JENDL-HE and the LA150 evaluated nuclear data files, the ISOBAR model implemented in PHITS, and the LAHET code in MCNPX. It was found that these calculated results at 0 generally agreed with the experimental results in the energy range above 20 MeV except for graphite at 250 and 350 MeV.

Measurement of neutron spectra produced in the forward direction from thick graphite, Al, Fe and Pb targets bombarded by 350 MeV protons

Iwamoto, Yosuke; Taniguchi, Shingo*; Nakao, Noriaki*; Itoga, Toshio*; Nakamura, Takashi*; Nakane, Yoshihiro; Nakashima, Hiroshi; Satoh, Daiki; Yashima, Hiroshi*; Yamakawa, Hiroshi*; et al.

Nuclear Instruments and Methods in Physics Research A, 562(2), p.789 - 792, 2006/06

https://doi.org/10.1016/j.nima.2006.02.056

Neutron energy spectra produced from thick targets play an important role in validation of calculation codes that are employed in the design of spallation neutron sources and the shielding design of accelerator facilities. However, appropriate experimental data were scarce in the forward direction for the incident energy higher than 100 MeV. In this study, neutron spectra at 0 degree from thick targets bombarded with 350 MeV protons were measured by the time-of-flight technique using an NE213. The targets used were graphite, Al, Fe and Pb and their thicknesses were chosen to be a little thicker than the stopping lengths. The experiment was carried out at the TOF course of the RCNP (Research Center of Nuclear Physics) ring cyclotron, Osaka University. The flight path length between center of the target and of an NE213 were 11.4 m for the measurement of low energy neutrons and 95 m for high energy neutrons. The experimental data are compared with the calculated results by using the Monte Carlo transport codes, such as MCNPX and PHITS codes.

Absolute measurements of activation cross sections of Al(n,p)Mg, Al(n,)Na, Fe(n,p)Mn, Zr(n,2n)Zr and Nb(n,2n)Nb at energy range of 13.314.9MeV

Ikeda, Yujiro; Konno, Chikara; Oyama, Yukio; Kosako, Kazuaki*; *; Maekawa, Hiroshi

Journal of Nuclear Science and Technology, 30(9), p.870 - 880, 1993/09

https://doi.org/10.3327/jnst.30.870

no abstracts in English

Activation cross section measurements on fusion reactor structural materials at neutron energy from 13.3 to 15.0 MeV using FNS facility

Ikeda, Yujiro; Konno, Chikara; *; Nakamura, Tomoo; *; Kawade, Kiyoshi*; Yamamoto, Hiroshi*; Kato, Toshio*

JAERI 1312, 112 Pages, 1988/03

JAERI-1312.pdf:2.42MB

no abstracts in English

Measured neutron parameters for phase 1 experiments at the FNS facility

; ; ; ; ; ; *; K.G.Porges*; E.F.Bennett*; T.J.Yule*; et al.

Transactions of the American Nuclear Society, 52, p.109 - 110, 1986/00

no abstracts in English