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排序方式: 共有716条查询结果,搜索用时 15 毫秒
711.
Yutaka Mori Tomoya Yamauchi Masato Kanasaki Yusuke Maeda Keiji Oda Satoshi Kodaira Teruaki Konishi Nakahiro Yasuda Rémi Barillon 《Radiation measurements》2011,46(10):1147-1153
Chemical modification along ion tracks in PADC films has been studied by means of FT-IR spectrometry, which was exposed to proton and heavy ions of He, C, Ne, Ar, Fe, Kr and Xe with energies around the Bragg peaks. This study covers a wide region of the stopping power ranging from 10 to 10,000 keV/μm. Removal cross sections for the loss of ether and carbonate ester bonds are assessed for each ion, as a function of the stopping power. Chemical damage parameters like the damage density, the effective track core radius and the radiation chemical yields, G values (scissions/100 eV), for each bond are also derived. We have found anomalous dependence of these parameters on the stopping power. The G value for the loss of carbonate ester bond decreased from 20 for proton down to 5 for C and Ne ions, and then increased with atomic number of heavy ions up to 8 for Xe ion. Radial dose distribution for each ion has been also calculated. Results are discussed from the viewpoint of polymeric structure of PADC that consists of two parts with different radio-sensitivities. 相似文献
712.
We theoretically study possible methods how to obtain imaging of magnetic atoms by use of photoelectron diffraction (PD). We propose a novel method to apply Daimon effect where PD peaks are rotated around forward focusing peaks. In usual circular dichroism, we simply use the difference of the PD intensities for different X-ray circular polarization. In contrast to this dichroism, we rather use the difference of the PD intensities for different circular polarizations but - is used for the – circular polarization only in the data handling. This technique allows us to obtain clear atomic image only of spin polarized atoms, and to distinguish magnetic atoms with up-spins from those with down spins. Some illustrative calculations demonstrate the potential use and also the limitation of this technique. 相似文献
713.
Abe S Ebihara T Enomoto S Furuno K Gando Y Ichimura K Ikeda H Inoue K Kibe Y Kishimoto Y Koga M Kozlov A Minekawa Y Mitsui T Nakajima K Nakajima K Nakamura K Nakamura M Owada K Shimizu I Shimizu Y Shirai J Suekane F Suzuki A Takemoto Y Tamae K Terashima A Watanabe H Yonezawa E Yoshida S Busenitz J Classen T Grant C Keefer G Leonard DS McKee D Piepke A Decowski MP Detwiler JA Freedman SJ Fujikawa BK Gray F Guardincerri E Hsu L Kadel R Lendvai C Luk KB Murayama H O'Donnell T Steiner HM Winslow LA 《Physical review letters》2008,100(22):221803
The KamLAND experiment has determined a precise value for the neutrino oscillation parameter Deltam21(2) and stringent constraints on theta12. The exposure to nuclear reactor antineutrinos is increased almost fourfold over previous results to 2.44 x 10(32) proton yr due to longer livetime and an enlarged fiducial volume. An undistorted reactor nu[over]e energy spectrum is now rejected at >5sigma. Analysis of the reactor spectrum above the inverse beta decay energy threshold, and including geoneutrinos, gives a best fit at Deltam21(2)=7.58(-0.13)(+0.14)(stat) -0.15+0.15(syst) x 10(-5) eV2 and tan2theta12=0.56(-0.07)+0.10(stat) -0.06+0.10(syst). Local Deltachi2 minima at higher and lower Deltam21(2) are disfavored at >4sigma. Combining with solar neutrino data, we obtain Deltam21(2)=7.59(-0.21)+0.21 x 10(-5) eV2 and tan2theta12=0.47(-0.05)+0.06. 相似文献
714.
Iwabuchi M Nakao M Adachi I Arinstein K Aulchenko V Aushev T Bakich AM Balagura V Barberio E Bay A Belous K Bhardwaj V Bitenc U Bozek A Bracko M Browder TE Chen A Chen WT Cheon BG Cho IS Choi Y Dalseno J Dash M Drutskoy A Eidelman S Fujikawa M Gabyshev N Ha H Haba J Hayasaka K Hazumi M Heffernan D Horii Y Hoshi Y Hou WS Hyun HJ Inami K Ishikawa A Ishino H Itoh R Iwasaki M Kah DH Kaji H Kang JH Kawai H Kawasaki T Kichimi H Kim HJ Kim HO Kim YI Kim YJ Kinoshita K Korpar S Krizan P Krokovny P 《Physical review letters》2008,101(4):041601
We report on a search for the doubly Cabibbo suppressed decay B+-->D*+pi0, based on a data sample of 657x10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find no significant signal and set an upper limit of B(B+-->D*+pi0)<3.6x10(-6) at the 90% confidence level. This limit can be used to constrain the ratio between suppressed and favored B-->D*pi decay amplitudes, r<0.051, at the 90% confidence level. 相似文献
715.
716.