Refine your search:     
Report No.
 - 
Search Results: Records 1-12 displayed on this page of 12
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Dipole strength distributions in $$^{56}$$Fe

Shizuma, Toshiyuki; Hayakawa, Takehito; Ogaki, Hideaki; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*; Kikuzawa, Nobuhiro; Inakura, Tsunenori*; Homma, Michio*; Nakada, Hitoshi*

Physical Review C, 87(2), p.024301_1 - 024301_7, 2013/02

 Times Cited Count:15 Percentile:70.84(Physics, Nuclear)

Electro-magnetic dipole transitions in $$^{56}$$Fe were measured in photon scattering experiments with a linearly polarized photon beam. The parity quantum numbers of the excited dipole states were determined by the intensity asymmetry of resonantly scattered $$gamma$$-rays with respect to the polarization plane of the incident photon beam. While the summed magnetic dipole ($$M1$$) strength was determined as $$Sigma B(M1)!uparrow=3.52(17)$$ $$mu_N^2$$ at excitation energies between 7 and 10 MeV, the summed electric dipole ($$E1$$) strength below 10 MeV was obtained as $$Sigma B(E1)!uparrow=78.0(15)times10^{-3},e^2{rm fm}^2$$. The observed $$M1$$ strength was compared with shell-model predictions in the $$pf$$-shell using the GXPF1J and KB3G effective interactions. In addition, the $$E1$$ strength was compared with random-phase approximation calculations with the Skyrme interaction.

Journal Articles

Fine structure of the magnetic-dipole-strength distribution in $$^{208}$$Pb

Shizuma, Toshiyuki; Hayakawa, Takehito; Ogaki, Hideaki*; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*; Kikuzawa, Nobuhiro; Tamii, Atsushi*; Nakada, Hitoshi*

Physical Review C, 78(6), p.061303_1 - 061303_4, 2008/12

 Times Cited Count:75 Percentile:95.52(Physics, Nuclear)

Spin-flip $$M1$$ strength in $$^{208}$$Pb has been measured in photon scattering experiments with a quasi-monochromatic, linearly polarized photon beam. The data resolve an $$M1$$ giant resonance into at least seven, possibly eight, discrete transitions at excitation energies between 7.1 and 7.4 MeV below the neutron separation energy. The measured $$M1$$ strength in this region is found to be larger than the previous report. The experimental results are compared with an estimation of self-consistent random phase approximation using a semi-realistic interaction.

Journal Articles

Microstructure and residual stress of EB-PVD TBCs grown under substrate rotation

Suzuki, Kenji*; Shobu, Takahisa; Wada, Kunihiko*; Matsubara, Hideaki*; Kawamura, Masashi*

Zairyo, 57(7), p.674 - 680, 2008/07

Journal Articles

Residual stresses structure of EB-PVD thermal barrier coatings exposed at high temperature

Suzuki, Kenji*; Shobu, Takahisa; Wada, Kunihiko*; Matsubara, Hideaki*

Nihon Kikai Gakkai Rombunshu, A, 74(739), p.370 - 376, 2008/03

Thickness of the bond coating was about 0.18 mm, and the thickness of the top coating was about 0.12 mm. The rotation speeds of specimens in the EB-PVD process were 5 rpm, 10 rpm and 20 rpm. The specimens were oxidized at 1273 K for 200 h. The in-plane residual stress was measured by a conventional X-ray method, and the out-of-plane residual strain was measured by a strain scanning method with hard synchrotron X-rays. For the specimens with 5 rpm and 10 rpm, the in-plane compressive residual stresses were released by the oxidization. For the specimen with 20 rpm, the in-plane residual stress did not change by the oxidization, because it was very small before the oxidization. The in-plane residual stresses were large compression near the interface. For the specimens with 5 rpm and 10 rpm, the out-of-plane stresses were small from the coating surface but became a compression near the interface. Both in-plane and out-of-plane residual stresses of the specimen with 20 rpm were very small. In the effect of decreasing the residual stress, the rotation speed of 20 rpm was the excellent condition. According to the observation with a scanning electron microscope, the featherlike columnar structure decreased after the oxidization. This volume decrease caused the release of the in-plane residual stresses.

Journal Articles

Residual stress in zirconia coating by EB-PVD method

Suzuki, Kenji*; Wada, Kunihiko*; Matsubara, Hideaki*; Shobu, Takahisa; Kawamura, Masashi*; Tanaka, Keisuke*

Zairyo, 56(7), p.588 - 593, 2007/07

The Ni-based superalloy IN738LC was used as the substrate material, and CoNiCrAlY powder was pressureless plasma-sprayed on the substrate as the bond coating. Zirconia was coated as the top coating by the electron beam-physical vapor deposition (EV-PVD) method. In the EB-PVD process, the specimens were kept at 1223 K and rotated with 5 rpm, 10 rpm and 20 rpm. According to the microscopic observation and the result of the pole figures, the top coatings had a columnar structure, which was made by the piling up of (111) planes. The cross section of the column had a diamond shape, and its diagonal was parallel to the rotation axis. The residual stress on the surface of the top coatings was evaluated by the X-ray diffraction method. Each diffraction profile was separated into the 133 and the 331 peak, and the residual stress was measured by the sin$$^{2}$$ $$psi$$ method. The measured residual stresses were -76.6 MPa for 5 rpm, -63.0 MPa for 10 rpm and -25.1 MPa for 20 rpm.

Oral presentation

Measurements of E1, M1 and E2 transition strength in $$^{208}$$Pb using laser Compton scattering $$gamma$$ rays

Shizuma, Toshiyuki; Hayakawa, Takehito; Ogaki, Hideaki*; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*; Kikuzawa, Nobuhiro; Tamii, Atsushi*; Nakada, Hitoshi*

no journal, , 

no abstracts in English

Oral presentation

Photon scattering experiments on nuclei at iron region using a $$gamma$$-ray beam from inverse Compton scattering

Shizuma, Toshiyuki; Hayakawa, Takehito; Kikuzawa, Nobuhiro; Ogaki, Hideaki*; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*

no journal, , 

no abstracts in English

Oral presentation

Nuclear photon scattering experiments by quasi-monochromatic, linearly polarized light sources

Shizuma, Toshiyuki; Hayakawa, Takehito; Ogaki, Hideaki; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*; Kikuzawa, Nobuhiro; Tamii, Atsushi*; Nakada, Hitoshi*

no journal, , 

The knowledge of the M1 response allows one to elucidate the details of nuclear dynamics. It is also important for the estimate neutral current neutrino-nucleus cross sections for supernova explosion. Low-lying electromagnetic transitions can be studied by the method of nuclear resonance fluorescence (NRF). Recently, it has been shown that quasi-monochromatic, linearly polarized photon beams from inverse laser Compton scattering has considerably increased experimental sensitivity and to enable one to detect the fine structure of relatively weak M1 transitions. In this report, results of the NRF measurements on $$^{208}$$Pb using a linearly polarized photon beam will be presented. The M1 resonance below the neutron separation energy is resolved into several individual transitions. The experimental results are compared with an estimation of self-consistent random phase approximation using a semi-realistic interaction.

Oral presentation

Nuclear photon scattering experiments on $$^{56}$$Fe using laser Compton scattering $$gamma$$ rays

Shizuma, Toshiyuki; Hayakawa, Takehito; Kikuzawa, Nobuhiro; Ogaki, Hideaki; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*

no journal, , 

no abstracts in English

Oral presentation

Nuclear resonance fluorescence measurements by quasi-monochromatic, linearly polarized photon beams

Shizuma, Toshiyuki; Hayakawa, Takehito; Ogaki, Hideaki; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*; Kikuzawa, Nobuhiro; Tamii, Atsushi*; Homma, Michio*; Nakada, Hitoshi*

no journal, , 

Low-lying electromagnetic transitions can be studied by the method of nuclear resonance fluorescence (NRF). Recently, it has been shown that quasi-monochromatic, linearly polarized photon beams from inverse laser Compton scattering has considerably increased experimental sensitivity and to enable one to detect the fine structure of relatively weak M1 transitions. In this report, results of the NRF measurements on nuclei around lead and iron region will be presented. The M1 resonance below the neutron separation energy is resolved in to individual transitions. The experimental results are compared with theoretical predictions based on self-consistent RPA and Shell model calculations. The role of the tensor interaction in giant M1 resonance region is discussed.

Oral presentation

Nuclear photon scattering and its application to nuclear physics investigation

Shizuma, Toshiyuki; Hayakawa, Takehito; Ogaki, Hideaki; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*

no journal, , 

Nuclear electromagnetic (EM) transitions can be studied by nuclear photon scattering, or nuclear resonance fluorescence (NRF). Recently, it was shown that a quasi-monochromatic, linearly polarized photon beam produced by inverse Compton scattering increased experimental sensitivities to distinguish between electric and magnetic dipole transitions. Here we report the results of the nuclear photon scattering measurements on $$^{56}$$Fe using a quasi-monochromatic, linearly polarized photon beam derived at National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba. Many dipole resonances below the neutron separation energy of $$^{56}$$Fe (11.2 MeV) have been observed. The multi-polarities of these transitions were determined by intensity asymmetry relative to the polarization of the incident photon beam. The experimental results are compared with a shell model calculation.

Oral presentation

Nuclear resonance fluorescence measurements on iron nuclei by using laser Compton $$gamma$$ rays

Shizuma, Toshiyuki; Hayakawa, Takehito; Kikuzawa, Nobuhiro; Ogaki, Hideaki; Toyokawa, Hiroyuki*; Komatsubara, Tetsuro*

no journal, , 

Nuclear resonance fluorescence (NRF) measurements on iron nuclei have been carried out by using laser Compton $$gamma$$ rays with high polarization. NRF scattering $$gamma$$ rays were measured by a Ge detector with a relative detection efficiency of 140%. Multi-polarities of the transitions were determined by intensity asymmetry of the transitions with respect to the polarization. Many electric- and magnetic- dipole transitions were observed. The measurement method and the experimental results will be reported.

12 (Records 1-12 displayed on this page)
  • 1