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31.
K Ogura M Nishiuchi AS Pirozhkov T Tanimoto A Sagisaka TZh Esirkepov M Kando T Shizuma T Hayakawa H Kiriyama T Shimomura S Kondo S Kanazawa Y Nakai H Sasao F Sasao Y Fukuda H Sakaki M Kanasaki A Yogo SV Bulanov PR Bolton K Kondo 《Optics letters》2012,37(14):2868-2870
Using a high-contrast (10(10):1) and high-intensity (10(21) W/cm(2)) laser pulse with the duration of 40 fs from an optical parametric chirped-pulse amplification/Ti:sapphire laser, a 40 MeV proton bunch is obtained, which is a record for laser pulse with energy less than 10 J. The efficiency for generation of protons with kinetic energy above 15 MeV is 0.1%. 相似文献
32.
K. Tshoo Y. Satou H. Bhang S. Choi T. Nakamura S. Deguchi Y. Kawada Y. Kondo N. Kobayashi Y. Nakayama K. N. Tanaka N. Tanaka N. Aoi M. Ishihara T. Motobayashi H. Otsu H. Sakurai S. Takeuchi Y. Togano K. Yoneda Z. H. Li F. Delaunay J. Gibelin F. M. Marques N. A. Orr T. Honda M. Matsushita T. Kobayashi Y. Miyashita T. Sumikama K. Yoshinaga S. Shimoura D. Sohler T. Zheng Z.X. Cao 《Few-Body Systems》2013,54(1-4):459-463
The unbound excited states of the most neutron-rich dripline oxygen isotope, 24O, have been investigated by using the 24O(p,p′)24O* reaction at the beam energy of 62 MeV/nucleon in inverse kinematics. The first and second unbound excited states of 24O have been observed at ${E_{\rm x}= 4.63_{-0.14}^{+0.30}}$ MeV and ${E_{\rm x}= 5.13_{-0.24}^{+0.19}}$ MeV (preliminary) along with the evidence for another higher lying state at around 7.3 MeV. The quadrupole deformation parameter ${\beta_{2^+}}$ was deduced to be ${0.15_{-0.03}^{+0.08}}$ (preliminary) for the first time. The systematics of the ${\beta_{2^+}}$ and the ${E_{\rm x}(2_1^+)}$ in the Z = 8 isotopes shows the N = 16 spherical shell closure in 24O. 相似文献
33.
The positron annihilation lifetime method (PAL) has been applied to study the characteristics of polyethylenes (PEs) at low temperatures between 273 and 100 K. It has been found that the intensity (I
3) of the long-lived component of positronium (Ps) showed an increase in non-annealed PE and annealed PE in vacuo. However, PAL in PEs annealed in an atmosphere containing oxygen did not show such an increase. It has been indicated that the latter effect is due to formation of carbonyl groups through oxidation during the annealing. 相似文献
34.
Abstract Color centers in rutile-structured MgF2 single crystals irradiated at 20K/360K by reactor neutrons are investigated spectroscopically at LNT. Four different types of the F-F vacancy bond in MgF2 are possibly identified to the observed absorption bands as due to the F2 centers; instead of previous assignments, the 300nm band to the F2(D2h), the 325nm band to the F2(C1), the 355nm band to the F2(C2v), and the 400nm band to the F2(C2h) centers. 相似文献
35.
Fourier transform spectra recorded using (a) natural abundance water vapor, (b) H218O-enriched water vapor, and (c) H217O-enriched water vapor are analyzed. The ratio of intensities in three spectra is used to identify 927 lines due to absorption by H218O. Intensities and self-broadening parameters are derived for these lines. Using theoretical linelists, comparisons with previously assigned H216O spectra, and automatic searches for combination differences, 747 lines are assigned. These lines belong to 14 vibrational states in the 3ν+δ and 4ν polyads. Newly determined H218O vibrational band origins include 4ν1 at 13 793.09 cm−1, 3ν1+ν3 at 13 795.40 cm−1, 2ν1+2ν3 at 14 188.82 cm−1, ν1+3ν3 at 14 276.34 cm−1, and 2ν2+2ν2+ν3 at 13 612.71 cm−1. These results are compared with data in HITRAN. 相似文献
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38.
Hideo Kaiju Akito Ono Kenji Kondo Jonghan Won Manabu Ishimaru 《Applied Surface Science》2009,255(6):3706-3712
We study the structural properties of the surface roughness, the surface mound size and the interfacial structure in Ni thin films vacuum-deposited on polyethylene naphthalate (PEN) organic substrates with and without the application of magnetic field and discuss its feasibility of fabricating quantum cross (QC) devices. For Ni/PEN evaporated without the magnetic field, the surface roughness decreases from 1.3 nm to 0.69 nm and the surface mound size increases from 32 nm to 80 nm with the thickness increased to 41 nm. In contrast, for Ni/PEN evaporated in the magnetic field of 360 Oe, the surface roughness tends to slightly decrease from 1.3 nm to 1.1 nm and the surface mound size shows the almost constant value of 28-30 nm with the thickness increased to 35 nm. It can be also confirmed for each sample that there is no diffusion of Ni into the PEN layer, resulting in clear Ni/PEN interface and smooth Ni surface. Therefore, these experimental results indicate that Ni/PEN films can be expected as metal/insulator hybrid materials in QC devices, leading to novel high-density memory devices. 相似文献
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40.
Y. KatoD. Ichii K. OhashiH. Kunugita K. Ema K. TanakaT. Takahashi T. Kondo 《Solid State Communications》2003,128(1):15-18
We have confirmed biexciton formation in an organic-inorganic hybrid quantum-well material (C4H9NH3)2PbBr4 by photoluminescence and two-photon absorption measurements. The biexciton has extremely large binding energy, 60 meV, which to our knowledge is the largest value ever reported for a semiconductor. By analyzing the spectrum of biexciton luminescence, the biexciton gas temperature was found to be much higher than the bath temperature due to a higher local temperature arising from the large biexciton binding energy. 相似文献