Experimental study of Gamow-Teller transitions via the high-energy-resolution O(He,)F reaction; Identification of the low-energy "super" -Gamow-Teller state

Fujita, Hirohiko*; Fujita, Yoshitaka*; Utsuno, Yutaka; Yoshida, Kenichi*; Adachi, Tatsuya*; Algora, A.*; Csatls, M.*; Deaven, J. M.*; Estevez-Aguado, E.*; Guess, C. J.*; et al.

Physical Review C, 100(3), p.034618_1 - 034618_13, 2019/09

AA2019-0318.pdf:1.1MB

https://doi.org/10.1103/PhysRevC.100.034618

no abstracts in English

Shielding experiments of concrete and iron for the 244 MeV and 387 MeV quasi-mono energetic neutrons using a Bonner sphere spectrometer (at RCNP, Osaka Univ.)

Matsumoto, Tetsuro*; Masuda, Akihiko*; Nishiyama, Jun*; Iwase, Hiroshi*; Iwamoto, Yosuke; Satoh, Daiki; Hagiwara, Masayuki*; Yashima, Hiroshi*; Yashima, Hiroshi*; Shima, Tatsushi*; et al.

EPJ Web of Conferences, 153, p.08016_1 - 08016_3, 2017/09

https://doi.org/10.1051/epjconf/201715308016

Neutron energy spectra behind concrete and iron shields were measured for quasi-monoenergetic neutrons above 200 MeV using a Bonner sphere spectrometer (BSS). Quasi-monoenergetic neutrons were produced by the Li(p,xn) reaction with 246-MeV and 389-MeV protons. The response function of BSS was also measured at neutron energies from 100 MeV to 387 MeV. In data analysis, the measured response function was used and the multiple neutron scattering effect between the BSS and the shielding material was considered. The neutron energy spectra behind the concrete and iron shields were obtained by the unfolding method using the MAXED code. Ambient dose equivalents were obtained as a function of a shield thickness successfully. For the case of the 244 MeV neutron incidence, the multiple neutron scattering effect on the effective dose is large under 50 cm thickness of the concrete shield.

A Non-destructive profile monitor using a gas sheet

Ogiwara, Norio; Hikichi, Yusuke; Namekawa, Yuya; Kamiya, Junichiro; Kinsho, Michikazu; Hatanaka, Kichiji*; Shima, Tatsushi*; Fukuda, Mitsuhiro*

Proceedings of 7th International Particle Accelerator Conference (IPAC '16) (Internet), p.2102 - 2104, 2016/06

https://doi.org/10.18429/JACoW-IPAC2016-WEOBB03

Quasi-monoenergetic neutron beam and its application at the RCNP cyclotron facility

Iwamoto, Yosuke; Yashima, Hiroshi*; Satoh, Daiki; Hagiwara, Masayuki*; Iwase, Hiroshi*; Nakamura, Takashi*; Shima, Tatsushi*; Tamii, Atsushi*; Hatanaka, Kichiji*

IAEA-TECDOC-1743, Annex (CD-ROM), p.177 - 188, 2014/07

https://www-nds.iaea.org/publications/tecdocs/iaea-tecdoc-1743/

A quasi-monoenergetic neutron field using Li(p,n) reaction for the higher energy range of 100 to 400 MeV has been developed at the RCNP cyclotron facility of Osaka University. The neutron energy spectra at angles from 0 to 30 have been investigated for the proton beams with the energies of 140, 250, 350 and 392 MeV. The highest neutron fluence reaches 1.0 10 n/sr/C, and the contribution of peak intensity to the total intensity varied between 0.4 and 0.5. Using the quasi-monoenergetic neutron beam, measurement of neutron induced activation cross sections, elastic scattering cross sections for neutron and a shielding benchmark experiment have been performed, successfully. Thus quasi-monoenergetic neutron field at RCNP are suitable for measurement of nuclear data, shielding experiments and the calibration of monitors in the energy region from 100 to 400 MeV.

Characterization of quasi-monoenergetic neutron source using 137, 200, 246 and 389 MeV Li(p,n) reactions

Iwamoto, Yosuke; Hagiwara, Masayuki*; Iwase, Hiroshi*; Yashima, Hiroshi*; Satoh, Daiki; Matsumoto, Tetsuro*; Masuda, Akihiko*; Pioch, C.*; Mares, V.*; Shima, Tatsushi*; et al.

Progress in Nuclear Science and Technology (Internet), 4, p.657 - 660, 2014/04

https://doi.org/10.15669/pnst.4.657

The authors measured the neutron energy spectra of the proton incident reaction on the lithium target with 137, 200, 246 and 389 MeV protons at several angles (0, 2.5, 5, 10, 15, 20, 25 and 30), using a time-of-flight (TOF) method employing organic scintillators NE213 at the Research Center for Nuclear Physics (RCNP) of Osaka University. For the neutron energy spectrum at 0, the ratio of the peak neutron intensity to the total one varied between 0.4 and 0.5 depending on the incident energy. In order to consider the correction required to derive the response in the peak region from the measured total response for high-energy neutron detectors, the authors showed the subtractions of H*(10) obtained at larger angles from the 0 data in the continuum part. It was found that subtracting the dose equivalent at about 22 from the 0 data reduces the continuum component most efficiency.

Shielding benchmark experiment using hundreds of MeV quasi-monoenergetic neutron source by a large organic scintillator

Hagiwara, Masayuki*; Iwase, Hiroshi*; Iwamoto, Yosuke; Satoh, Daiki; Matsumoto, Tetsuro*; Masuda, Akihiko*; Yashima, Hiroshi*; Nakane, Yoshihiro; Nakashima, Hiroshi; Sakamoto, Yukio; et al.

Progress in Nuclear Science and Technology (Internet), 4, p.327 - 331, 2014/04

https://doi.org/10.15669/pnst.4.327

We have developed several hundreds of MeV p-Li quasi-monoenergetic neutron fields in the Research Center for Nuclear Physics (RCNP), Osaka University, Japan. In this study, we extended the measurements to higher energy with a p-Li quasi-monoenergetic neutron source, which was produced from a 1.0-cm-thick lithium target bombarded with 246 and 389 MeV protons, using a larger NE213 scintillator of 25.4-cm in diameter and 25.4-cm in thickness. The large NE213 have good energy resolution for high energy neutrons, because it can stop recoil protons up to 180 MeV. The measured data are compared with the Monte-Carlo codes (PHITS with JENDL-HE data library) in the energy spectra, time spectra and the attenuation length of the peak neutrons. This comparison shows good agreement between experiments and calculations. The attenuation length estimated from the well-fitted curves with single exponential form will be useful for the practical shielding design of high energy accelerator facilities.

Response measurement of a Bonner sphere spectrometer for high-energy neutrons

Masuda, Akihiko*; Matsumoto, Tetsuro*; Harano, Hideki*; Nishiyama, Jun*; Iwamoto, Yosuke; Hagiwara, Masayuki*; Satoh, Daiki; Iwase, Hiroshi*; Yashima, Hiroshi*; Nakamura, Takashi*; et al.

IEEE Transactions on Nuclear Science, 59(1), p.161 - 166, 2012/02

https://doi.org/10.1109/TNS.2011.2175406

In this study, responses of Bonner sphere spectrometer (BSS) for 245 and 388 MeV neutrons was measured at RCNP, Osaka University. The neutrons are generated in the Li(p,n) reaction and its spectra consist of a high-energy peak and a continuum down to the low energy. Therefore, the observed counts of BSS caused by the continuum need to be subtracted. Adjusting a Li target angle and a collimator position, 0 deg and 30 deg component of generated neutron are available. While the 0 deg component contains both the peak and the continuum, the 30 deg component is considered to contain only the continuum. Therefore, the response of the peak is obtained. The spectra were measured using the time-of-flight (TOF) method with a NE213 scintillator.

Characterisation of quadi-monoenergetic neutron energy spectra using Li(p,n) reactions at 246-389 MeV

Iwamoto, Yosuke; Hagiwara, Masayuki*; Satoh, Daiki; Iwase, Hiroshi*; Yashima, Hiroshi*; Itoga, Toshiro*; Sato, Tatsuhiko; Nakane, Yoshihiro; Nakashima, Hiroshi; Sakamoto, Yukio; et al.

Proceedings of 10th Meeting of the Task Force on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF-10), p.53 - 61, 2011/03

The neutron energy spectra penetrating 10 to 100 cm thick iron and 25 to 200 cm thick concrete shields have been measured using 138, 243 and 387 MeV quasi-monoenergetic neutron sources at the Research Center for Nuclear Physics (RCNP) facility, Osaka University. The source neutrons were produced from a 1 cm thick lithium target bombarded with 140, 245 and 388 MeV protons. Two types of NE213 liquid organic scintillators and Bonner ball neutron spectrometers were used for the neutron energy spectrum measurement. The TOF and unfolding methods were applied to estimate the energy spectra behind the shield in the peak energy region and continuous energy region, respectively. We have also measured the neutron energy spectra and angular distribution of the source neutron above 1 MeV in the angular range from 0 to 30 with the TOF method. All measured data were compared with the PHITS Monte Carlo calculations.

Evaluation of the white neutron beam spectrum for single-event-effects testing at the RCNP cyclotron facility

Iwamoto, Yosuke; Fukuda, Mitsuhiro*; Sakamoto, Yukio; Tamii, Atsushi*; Hatanaka, Kichiji*; Takahisa, Keiji*; Nagayama, Keiichi*; Asai, Hiroaki*; Sugimoto, Kenji*; Nashiyama, Isamu*

Nuclear Technology, 173(2), p.210 - 217, 2011/02

https://doi.org/10.13182/NT11-A11550

The 30 white neutron beam at RCNP facility has been characterized as a prove suitable for testing of single event effects (SEEs) in semiconductors in the neutron energy range from 1 to 300 MeV using the 392-MeV proton incident reaction on a 6.5-cm-thick tungsten target. The neutron spectrum in measurements were demonstrated to provide a neutron spectrum similar to the terrestrial one at sea level, but with an enhancement in the intensity of a factor of 1.510. The average neutron intensity and spectrum from 10 to 300 MeV at RCNP were almost same as those at WNR. The calculated RCNP neutron flux using PHITS generally agreed with the measured RCNP data within a factor of two. As the neutron density per pulse for RCNP is 500 times lower than that for WNR, the pileup probability of single-event transient currents and false multiple-bit upsets is reduced. Such conditions at RCNP are suitable for accelerated SEE testing to get meaningful results in realistic time frame.

Measurement of neutron elastic scattering cross sections for carbon at 134 MeV

Satoh, Daiki; Iwamoto, Yosuke; Hagiwara, Masayuki*; Iwase, Hiroshi*; Yashima, Hiroshi*; Sato, Tatsuhiko; Endo, Akira; Sakamoto, Yukio; Nakane, Yoshihiro; Nakashima, Hiroshi; et al.

Radiation Measurements, 45(10), p.1159 - 1162, 2010/12

https://doi.org/10.1016/j.radmeas.2010.06.064

Elastic neutron-scattering cross sections for carbon nucleus have been measured by using 134-MeV monoenergetic neutron beam in Research Center for Nuclear Physics (RCNP), Osaka University. The measured angles were set at 6, 8, and 15 in laboratory system. The liquid organic scintillators, whose size is 12.7 cm in diameter and 12.7 cm in thickness, were mounted at each angle as neutron detector. In the off-line analysis, the events of elastic-neutron scattering were extracted on basis of the Time-of-Flight (TOF) information. The results were compared with the data measured by the groupe of U.C. Davis with a recoil proton spectrometer and the evaluations of the nuclear data libraries, JENDL/HE-2007 and ENDF/B-VII.0. Our results show a good agreement with the data of U.C. Davis. This indicates that our experimental method based on the TOF teqnique is appropriate to the measurement of elastic neutron-scattering cross section in this energy region. In addition, we exhibit that the data of ENDF/B-VII.0 represent the experimental data, but JENDL/HE-2007 underestimates about 30 in the forward angle region.