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81.
We report NMR measurements of metallic (133)Cs in glass cells. The solid-liquid phase transition was studied by observing the NMR peaks arising from these two phases; surprisingly, many cells yielded two additional NMR peaks below the melting point. We attribute these signals to two distinct impurities which can dissolve in the liquid alkali metal and affect its chemical shift. Intentional contamination of cesium cells with O(2) confirms this hypothesis for one peak. The other contaminant remains unknown but can appear in evacuated cells. Similar effects have been seen in (87)Rb cells. 相似文献
82.
Drutskoy A Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aulchenko V Aushev T Banerjee S Barberio E Barbero M Bedny I Belous K Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Go A Gokhroo G Goldenzweig P Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Higuchi T 《Physical review letters》2007,98(5):052001
The inclusive production of D(s), D(0), and J/psi mesons is studied using a 1.86 fb(-1) data sample collected on the Upsilon(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The number of bb events in this Upsilon(5S) data sample is determined. We measure the branching fractions B(Upsilon(5S)-->D(s)X)/2=(23.6+/-1.2+/-3.6)%, B(Upsilon(5S)-->D(0)X)/2=(53.8+/-2.0+/-3.4)%, and B(Upsilon(5S)-->J/psiX)/2=(1.030+/-0.080+/-0.067)%. From the D(s) and D(0) inclusive branching fractions the ratio f(s)=(18.0+/-1.3+/-3.2)% of B(s)(*)B(s)(*) to the total bb quark pair production at the Upsilon(5S) energy is obtained in a model-dependent way. 相似文献
83.
84.
Abe K Adachi I Aihara H Arinstein K Asano Y Aulchenko V Aushev T Aziz T Bakich AM Balagura V Barbero M Bedny I Bitenc U Bizjak I Bondar A Bracko M Brodzicka J Browder TE Chao Y Chen A Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Gokhroo G Golob B Ha HC Haba J Hasegawa Y Hayasaka K Hayashii H Hazumi M Hinz L Hoshi Y Hou S Hou WS Hsiung YB Iijima T Ishikawa A Iwasaki M Iwasaki Y Kapusta P 《Physical review letters》2007,98(8):082001
We report the first observation of a charmoniumlike state recoiling from the J/psi in the inclusive process e+e- -->J/psi+anything at a mass of (3.943+/-0.006+/-0.006) GeV/c{2}. We also observe the decay of this state into D*D[over ] and determine its intrinsic width to be less than 52 MeV/c{2} at the 90% C.L. These results are obtained from a 357 fb{-1} data sample collected with the Belle detector near the Upsilon(4S) resonance, at the KEKB asymmetric-energy e+e- collider. 相似文献
85.
Li J Adachi I Aihara H Arinstein K Asner DM Aulchenko V Aushev T Bakich AM Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Brovchenko O Browder TE Chang MC Chen A Chen P Cheon BG Chistov R Cho K Choi SK Choi Y Dalseno J Doležal Z Drutskoy A Eidelman S Esen S Fast JE Gaur V Garmash A Goh YM Haba J Hara T Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Inami K Ishikawa A Itoh R Iwabuchi M Iwasaki Y Iwashita T Julius T Kang JH Kapusta P Katayama N Kawasaki T 《Physical review letters》2012,108(18):181808
We report first observations of B(s)(0) → J/ψη and B(s)(0) → J/ψη'. The results are obtained from 121.4 fb(-1) of data collected at the Υ(5S) resonance with the Belle detector at the KEKB e+ e- collider. We obtain the branching fractions B(B(s)(0) → J/ψη)=[5.10±0.50(stat)±0.25(syst)(-0.79)(+1.14)(N(B(s)(*) B(s)(*))]×10(-4), and B(B(s)(0) → J/ψη')=[3.71±0.61(stat)±0.18(syst)(-0.57)(+0.83)(N(B(s)(*) B(s)(*))]×10(-4). The ratio of the two branching fractions is measured to be (B(B(s) → J/ψη'))/(B(B(s) → J/ψη))=0.73±0.14(stat)±0.02(syst). 相似文献
86.
87.
WeiPing Liu ZhiHong Li JiangJun He XiaoDong Tang Gang Lian Zhu An JianJun Chang Han Chen QingHao Chen XiongJun Chen ZhiJun Chen BaoQun Cui XianChao Du ChangBo Fu Lin Gan Bing Guo GuoZhu He Alexander Heger SuQing Hou HanXiong Huang Ning Huang BaoLu Jia LiYang Jiang Shigeru Kubono JianMin Li KuoAng Li Tao Li YunJu Li Maria Lugaro XiaoBing Luo HongYi Ma ShaoBo Ma DongMing Mei YongZhong Qian JiuChang Qin Jie Ren YangPing Shen Jun Su LiangTing Sun WanPeng Tan Isao Tanihata Shuo Wang Peng Wang YouBao Wang Qi Wu ShiWei Xu ShengQuan Yan LiTao Yang Yao Yang XiangQing Yu Qian Yue Sheng Zeng HuanYu Zhang Hui Zhang LiYong Zhang NingTao Zhang QiWei Zhang Tao Zhang XiaoPeng Zhang XueZhen Zhang ZiMing Zhang Wei Zhao Zuo Zhao Chao Zhou JUNA Collaboration 《中国科学:物理学 力学 天文学(英文版)》2016,59(4):642001
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of~(25)Mg(p,γ)~(26)Al,~(19)F(p,α)~(16)O,~(13)C(α,n)~(16)O and ~(12)C(α,γ)~(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given. 相似文献
88.
Kiryu S Inoue Y Watanabe M Izawa K Shimada M Tojo A Yoshikawa K Ohtomo K 《Magnetic resonance imaging》2009,27(1):101-107
We investigated the characteristics of gadoxetate disodium (Gd-EOB-DTPA) as a contrast agent for magnetic resonance imaging of the mouse liver. Mice were imaged sequentially under isoflurane anesthesia using a T1-weighted, three-dimensional fast low-angle shot (3D FLASH) sequence after an intravenous injection of Gd-EOB-DTPA or gadobenate dimeglumine (Gd-BOPTA), and the time course of the contrast effect was examined. The time course of the contrast effect of Gd-EOB-DTPA was also assessed after intravenous injection under pentobarbital anesthesia and after subcutaneous injection while awake or under isoflurane or pentobarbital anesthesia. Moreover, different doses of Gd-EOB-DTPA or Gd-BOPTA were injected subcutaneously into conscious mice, and the clarity of the liver border was evaluated visually. Intravenous injection under isoflurane anesthesia caused rapid contrast enhancement in the liver with both Gd-EOB-DTPA and Gd-BOPTA, and the contrast effect was 41% stronger with Gd-EOB-DTPA. Subcutaneous injection of Gd-EOB-DTPA caused delayed but favorable contrast enhancement in the liver. Washout of Gd-EOB-DTPA was faster in mice injected while awake than in those injected under anesthesia. After intravenous injection, washout was faster under pentobarbital anesthesia than under isoflurane anesthesia. The peak liver contrast was 11% and 18% stronger under pentobarbital anesthesia than under isoflurane anesthesia, after intravenous and subcutaneous injections, respectively. Subcutaneous injection of Gd-EOB-DTPA or Gd-BOPTA caused dose-dependent contrast effects in the liver. At a given dose, the contrast effect tended to be stronger and liver demarcation tended to be clearer with Gd-EOB-DTPA than with Gd-BOPTA. In conclusion, intravenous or subcutaneous injection of Gd-EOB-DTPA produces a favorable contrast effects in the mouse liver, indicating its potential in investigating mouse models of liver diseases. The contrast effects vary between conscious mice and anesthetized mice and among anesthetic agents used. 相似文献
89.
We generalize the second law of thermodynamics in its maximum work formulation for a nonequilibrium initial distribution. It is found that in an isothermal process, the Boltzmann relative entropy (H-function) is not just a Lyapunov function but also tells us the maximum work that may be gained from a nonequilibrium initial state. The generalized second law also gives a fundamental relation between work and information. It is valid even for a small Hamiltonian system not in contact with a heat reservoir but with an effective temperature determined by the isentropic condition. Our relation can be tested in the Szilard engine, which will be realized in the laboratory. 相似文献
90.
Zegers RG Abend H Akimune H van den Berg AM Fujimura H Fujita H Fujita Y Fujiwara M Galès S Hara K Harakeh MN Ishikawa T Kawabata T Kawase K Mibe T Nakanishi K Nakayama S Toyokawa H Uchida M Yamagata T Yamasaki K Yosoi M 《Physical review letters》2003,90(20):202501
The excitation and subsequent proton decay of the isovector spin-flip giant monopole resonance (IVSGMR) is studied via the 208Pb(3He,t) reaction at 410 MeV. In the inclusive spectrum (60+/-5)% of the non-energy-weighted sum-rule strength for this 2 variant Planck's over 2h omega resonance was found in the region 29相似文献