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Cu and 
Cu using zinc target irradiated with accelerator neutronsKawabata, Masako; Hashimoto, Kazuyuki; Saeki, Hideya; Sato, Nozomi*; Motoishi, Shoji*; Nagai, Yasuki
no journal, ,
no abstracts in English
Minato, Futoshi; Nagai, Yasuki; Iwamoto, Nobuyuki; Iwamoto, Osamu
no journal, ,
Various kinds of radioactive isotopes (RIs) are widely used in nuclear medicine for diagnostics and therapy. Since the RIs are not usually present in the nature, they must be produced by nuclear reactors and accelerators. For instance, 
Tc is mainly produced by fission of highly enriched 
U (HEU) in nuclear reactors. However, use of the HEU is unfavorable in terms of nuclear security. Therefore, many methods without U have been studied in order to produce RIs for medical use; for example, thermal neutron capture, 
disintegration, and proton induced reactions. We also have proposed an alternative method using accelerator neutron besides the above methods. In this talk, we will show the features of RI productions with accelerator neutron which we have ever investigated and found, along with numerical results of RI yields calculated with Japanese Evaluated Nuclear Data Library (JENDL-4.0).
Hayakawa, Takehito; Negm, H.*; Ogaki, Hideaki*; Daito, Izuru*; Kii, Toshiteru*; Zen, H.*; Omer, M.*; Shizuma, Toshiyuki; Hajima, Ryoichi
no journal, ,
Recently, a nondestructive measurement method of shielded fissional isotopes such as U or 
Pu has been proposed for the nuclear security. These isotopes are measured by using nuclear resonance fluorescence (NRF) with monochromatic energy -ray beams generated by laser Compton-scattering (LCS). We have proposed that one measure scattered -rays from NRF with LCS -ray beams using the LaBr
(Ce) detectors. The LaBr(Ce) crystals include internal radioisotopes of a meta-stable isotope 
La and alpha decay chains from some actinides as 
Ac. There is a broad pump at about 2 MeV. This pump is considered to be an overlap of 
-rays from decay chains of some actinides but its detailed structure has not been established. Here we have measured NRF spectra of 
U using the LCS -rays with energy of about 2.5 MeV at the HIgS facility of the Duke University. The background has been evaluated using a simulation code GEAT4. The 9 peaks, 8 NRF -rays plus the Compton scattered -ray of the incident beam, are finally assigned in an energy range of about 200 keV at about 2.5 MeV. The 8 integrated NRF cross-sections measured by LaBr(Ce) have been consistent with results by an HPGe detector. The three levels are newly assigned using the HPGe detector. Two of them are also measured by LaBr(Ce).
Imai, Kenichi
no journal, ,
Recent Lattice QCD calculations have suggested a possible existence of H-dibaryon near the threshold. In the previous experiments at KEK-PS, a hint of peak structure was observed in the invariant mass spectrum at just above the threshold. An experiment to search for the H-dibaryon through 
p 
and 
mass spectra was proposed at J-PARC (E42). Much better statistics and mass resolution than the previous data are expected. For this experiment, we have been constructing a novel hyperon spectrometer with use of a GEM-TPC and a superconducting Helmholtz magnet. The expected performance of the spectrometer and the proposed experiment is reported based on the R&D results of the TPC and simulations. Possible physics with the hyperon spectrometer other than the H-dibaryon is also discussed.
Tc obtained from 
Mo produced by 
Mo(n,2n) using accelerator neutronsNagai, Yasuki; Kawabata, Masako; Sato, Nozomi*; Hashimoto, Kazuyuki; Saeki, Hideya; Motoishi, Shoji*; Hatsukawa, Yuichi; Ota, Akio; Shiina, Takayuki; Kawauchi, Yukimasa
no journal, ,
Tc, the daughter nuclide of Mo, is widely used for medical diagnosis. In Japan, about 0.9 million diagnostic procedures are carried out using Tc. Mo has been mostly produced using U in research reactors. Because of recent shortages of Mo, a variety of alternative production methods of Mo or Tc were proposed. We proposed to produce Mo by Mo(n,2n) using neutrons from an accelerator. The route is characterized to produce a large quantity of high-quality Mo with a minimum level of radioactive wastes, since the cross section of the Mo(n,2n)Mo reaction at 11 
En 18 MeV is large, and the cross sections of the (n,He), (n,n'p), and (n,p) reactions on Mo are quite small. Intense neutrons are available because of recent progresses of accelerator and target technologies. In the talk, we show our recent experimental results to obtain Tc with high-quality using Mo produced by Mo(n,2n).
Ichikawa, Yudai; Imai, Kenichi
no journal, ,
While the existence of kaonic nuclei has been intensively studied both theoretically and experimentally, there is no conclusive result establishing its existence.Here, we have searched for the 
, a bound state of a 
with two protons, in the 
reaction at 1.69 GeV/
at J-PARC K1.8 beam line with a missing-mass resolutionof 2.7 MeV/
(FWHM). In this reaction, the is assumed to be produced as 
as a doorwaysuch as 
, 
.Since the sticking probability of the 
on proton would not be so large, coincidence of high-momentum (
250 MeV/) proton(s) in large emission angles (
) was requested to enhance the signal-to-background ratio. We have obtained an inclusive 
spectrum in a wide missing-mass range from , 
to /
, for the first time. A proton coincidence spectrum shows a large proton-emission probability at around 2.27 GeV/ as a broad bump. It might be attributed to the production. A study of decay branch suggests non-mesonic decays of 
and 
are dominant rather than mesonic decays.
Sn studied via the 
Sn(d,t)Sn reactionOrlandi, R.; Pain, S. D.*; Bardayan, D. W.*; Gross, C. J.*; Smith, M. S.*; Jungclaus, A.*; Ahn, S.*; Jones, K. L.*; Pittman, S. T.*; Schmitt, K. T.*; et al.
no journal, ,
L
guillon, R.; Nishio, Katsuhisa; Hirose, Kentaro; Orlandi, R.; Makii, Hiroyuki; Nishinaka, Ichiro; Ishii, Tetsuro; Tsukada, Kazuaki; Asai, Masato; Chiba, Satoshi*; et al.
no journal, ,
82 nuclei at the JAEA Tandem FacilitySmallcombe, J.; Nishio, Katsuhisa; Hirose, Kentaro; Nishinaka, Ichiro; Makii, Hiroyuki; Orlandi, R.; Tamura, Nobuyuki*; Goto, Shinichi*; Otsuki, Tsutomu*; Andreyev, A.*; et al.
no journal, ,
Ekawa, Hiroyuki; Imai, Kenichi
no journal, ,
Koura, Hiroyuki
no journal, ,
An improvement of the gross theory of the 
decay has been carried out on -decay rate, 
, and beta-delayed neutron emission probability, 
. The gross theory is based on the sum rule of the -decay strength function, and has succeeded in describing -decay rate of nuclei in the entire nuclear region. The gross theory includes not only the allowed (Fermi and Gamow-Teller) transition, but also the 1st-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction for the nuclear level density and the nuclear deformation for the strength function, those effects were not included in the original gross theory. Considering the properties of the integrated Fermi function, three energy regions of the decay are classified: a higher energy region, which fully affects , a middle energy region, which contributes the decay heat, and a region neighboring the ground-state, which determines . Some results will be given in the presentation.
H hypernucleus via the (
) reaction at J-PARCSugimura, Hitoshi; Imai, Kenichi; Sako, Hiroyuki
no journal, ,
The research for neutron-rich hypernuclei are mainly studying at Japan and Europe. We have conducted the production experiment of H at J-PARC.H consists of four neutrons, one proton and one particle. Therefore N/Z ratio is very high. In such case, H makes very important role for researching the neutron star. So, We attempted to produce the hypernucleus and decided the upper limit of production cross section.