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821.
C. Amole M. D. Ashkezari G. B. Andresen M. Baquero-Ruiz W. Bertsche P. D. Bowe E. Butler C. L. Cesar S. Chapman M. Charlton A. Deller S. Eriksson J. Fajans T. Friesen M. C. Fujiwara D. R. Gill A. Gutierrez J. S. Hangst W. N. Hardy R. S. Hayano M. E. Hayden A. J. Humphries R. Hydomako S. Jonsell L. Kurchaninov N. Madsen S. Menary P. Nolan K. Olchanski A. Olin A. Povilus P. Pusa F. Robicheaux E. Sarid D. M. Silveira C. So J. W. Storey R. I. Thompson D. P. van der Werf J. S. Wurtele Y. Yamazaki 《Hyperfine Interactions》2012,212(1-3):101-107
The ALPHA experiment, located at CERN, aims to compare the properties of antihydrogen atoms with those of hydrogen atoms. The neutral antihydrogen atoms are trapped using an octupole magnetic trap. The trap region is surrounded by a three layered silicon detector used to reconstruct the antiproton annihilation vertices. This paper describes a method we have devised that can be used for reconstructing annihilation vertices with a good resolution and is more efficient than the standard method currently used for the same purpose. 相似文献
822.
In this work, we uncover the role of lasers pulse shaping for controlling the terahertz peaks with their separation in addition to their intensities. We have developed a mathematical model for obtaining the amplitude, frequency, and power of the emitted Terahertz radiation for the lasers whose shape is tailored based on the index and skew parameter. Then the results are compared with the case of Gaussian laser pulse in collisional plasma. We optimize the process by applying magnetic field and by varying the index of the lasers for compensating the negative influence of collisions on the THz emission. Specifically the effect of laser beam width, magnetic field and collision frequency is investigated on the electric field of the terahertz radiation and the efficiency of the mechanism. 相似文献
823.
Aubert B Barate R Boutigny D Couderc F Gaillard JM Hicheur A Karyotakis Y Lees JP Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Shelkov VG Wenzel WA Barrett M Ford KE Harrison TJ Hart AJ Hawkes CM Morgan SE 《Physical review letters》2004,93(18):181805
We measure the branching fractions and CP asymmetries in the decays B0-->K(+)K(-)K(0)(S) and B+-->K(+)K(0)(S)K(0)(S) using a sample of approximately 122x10(6) BB pairs collected by the BABAR detector. From a time-dependent analysis of the K(+)K(-)K(0)(S) sample that excludes phiK(0)(S), the values of the CP-violation parameters are S=-0.56+/-0.25+/-0.04 and C=-0.10+/-0.19+/-0.10, where the first uncertainty is statistical and the second is systematic. We confirm that the final state is nearly purely CP even and extract the standard model parameter sin(2beta=0.57+/-0.26+/-0.04(+0.17)(-0) where the last error is due to uncertainty on the CP content. We present the first measurement of the CP-violating charge asymmetry A(CP)(B+-->K(+)K(0)(S)K(0)(S))=-0.04+/-0.11+/-0.02. The branching fractions are B(B0-->K+K-K0)=(23.8+/-2.0+/-1.6)x10(-6) and B(B+-->K(+)K(0)(S)K(0)(S))=(10.7+/-1.2+/-1.0)x10(-6). 相似文献
824.
Aubert B Barate R Boutigny D Couderc F Gaillard JM Hicheur A Karyotakis Y Lees JP Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Shelkov VG Wenzel WA Barrett M Ford KE Harrison TJ Hart AJ Hawkes CM Morgan SE 《Physical review letters》2004,93(18):181801
We report a study of D(*)(sJ)(2317)(+) and D(sJ)(2460)(+) meson production in B decays. We observe the decays B+-->D((*)+)(sJ)D ((*)0) and B0-->D((*)+)(sJ)D((*)-) with the subsequent decays D(*)(sJ)(2317)(+)-->D(+)(s)pi(0), D(sJ)(2460)(+)-->D(+)(s)gamma, and D(sJ)(2460)(+)-->D(*+)(s)pi(0). Based on a data sample of 122.1 x 10(6) BB pairs collected with the BABAR detector at the PEP-II B factory, we obtain branching fractions for these modes, including the previously unseen decays B-->D((*)+)(sJ)D(*). In addition, we perform an angular analysis of D(sJ)(2460)(+)-->D(+)(s)gamma decays to test the different D(sJ)(2460)(+) spin hypotheses. 相似文献
825.
Aubert B Barate R Boutigny D Couderc F Gaillard JM Hicheur A Karyotakis Y Lees JP Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Shelkov VG Wenzel WA Barrett M Ford KE Harrison TJ Hart AJ Hawkes CM Morgan SE 《Physical review letters》2004,93(13):131801
We present a measurement of the direct CP violating asymmetry in the decay B0-->K+pi(-) using a data sample of 227x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at SLAC. We observe a total signal yield of nK-(pi(+))+nK+(pi(-))=1606+/-51 decays and measure the asymmetry (nK-(pi(+))-nK+(pi(-)))/(nK-(pi(+))+nK+(pi(-)))=-0.133+/-0.030(stat)+/-0.009(syst). The probability of observing such an asymmetry in the absence of direct CP violation is 1.3x10(-5), corresponding to 4.2 standard deviations. 相似文献
826.
International comparisons of I2 stabilized ion lasers operated at 514.5 nm have shown a laser frequency reproducibility of 2·10−10
v to 5·10−12
v. These results encouraged the international acceptance of the wavelength value λvac=514.673467 for thea
3 hyperfine component of the127I2 line 43-0P(13). 相似文献
827.
Laser diodes, optically narrowed using the technique of resonant optical feedback, have been frequency stabilised to hyperfine transitions of the two Rb D lines at 780 nm and 795 nm. The best frequency stability of the beat between two similar lasers was 1.5 kHz (4 parts in 1012 of the optical frequency) observed for an averaging time of 10 s. A frequency reproducibility of 44 kHz (one standard deviation) was observed on strong isolated hyperfine components, and possible causes of frequency shift were investigated. Values for the Rb hyperfine intervals were obtained, leading to an improved determination of the excited state hyperfine constants of 85Rb and 87Rb, and the isotope shift. The absolute frequencies of the hyperfine transitions of the two D lines were determined interferometrically by comparison with an 127I2-stabilised He-Ne laser at 633 nm. Measurements were made on component c at 795 nm and the d/f level crossing at 780 nm. The frequencies were found to be 377106271.6 MHz and 384227981.9 MHz respectively under the chosen conditions, with an uncertainty of ±0.4 MHz, limited by knowledge of the reference frequency. These results represent the most accurate and complete characterisation to date of laser diodes stabilised to Doppler-free Rb spectra. 相似文献
828.
In Tae Kim Sang Woo Lee Tae Hyoung Kwak Jung Youl Lee Hyang Suk Park So Young Kim Chang Min Lee Hoi Eun Jung Jun‐Gill Kang Tack‐Jin Kim Hee‐Jung Kang ChangMoon Park Ronald L. Elsenbaumer 《Macromolecular rapid communications》2002,23(9):551-554
Oxidative coupling reaction of 1‐hexyl–3,4‐dimethylpyrrole affords a conjugated conducting poly(1‐hexyl‐3,4‐dimethyl‐2,5‐pyrrolylene) (PHDP), which is completely soluble in common organic solvents. The luminescence of PHDP is comparable to that of poly(N‐vinylcarbazole) (PVK), which has been widely used in electroluminescence devices. The quantum efficiency of PHDP is 2.5 times higher than that of PVK. A rationalization is presented relating the conductivity of PHDP to its polymer structure. 相似文献
829.