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961.
Aggarwal MM Ahammed Z Alakhverdyants AV Alekseev I Alford J Anderson BD Anson CD Arkhipkin D Averichev GS Balewski J Beavis DR Bellwied R Betancourt MJ Betts RR Bhasin A Bhati AK Bichsel H Bielcik J Bielcikova J Biritz B Bland LC Borowski W Bouchet J Braidot E Brandin AV Bridgeman A Brovko SG Bruna E Bueltmann S Bunzarov I Burton TP Cai XZ Caines H Calderón de la Barca Sánchez M Cebra D Cendejas R Cervantes MC Chajecki Z Chaloupka P Chattopadhyay S Chen HF Chen JH Chen JY Cheng J Cherney M 《Physical review letters》2011,106(6):062002
We report the first measurement of the parity-violating single-spin asymmetries for midrapidity decay positrons and electrons from W+ and W- boson production in longitudinally polarized proton-proton collisions at sqrt[s] = 500 GeV by the STAR experiment at RHIC. The measured asymmetries, A(L)(W+) = -0.27 ± 0.10(stat.) ± 0.02(syst.) ± 0.03(norm.) and A(L)(W-) = 0.14 ± 0.19(stat.) ± 0.02(syst.) ± 0.01(norm.), are consistent with theory predictions, which are large and of opposite sign. These predictions are based on polarized quark and antiquark distribution functions constrained by polarized deep-inelastic scattering measurements. 相似文献
962.
Rativa D Gomes AS Wachsmann-Hogiu S Farkas DL de Araujo RE 《Journal of fluorescence》2008,18(6):1151-1155
We measured and analyzed the behavior of the fluorescence of tryptophan water solutions with and without silver nanoparticles,
excited by one, two and three photon processes. Two different colloids with silver nanoparticles with distinct diameters (0.65 nm
and 9 nm) were used in the experiments. Fluorescence quenching was observed with one and two photon excitation. However, upon
three-photon excitation, significant fluorescence enhancement was observed in the colloid. In this case excitation of the
amino acid is assisted by the nonlinear absorption of infrared light by the silver nanoparticles. In this paper we are proposing
a new way to explore metallic nanoparticles to enhance autofluorescence of biomolecules. 相似文献
963.
Anderson M Hirschmann EW Lehner L Liebling SL Motl PM Neilsen D Palenzuela C Tohline JE 《Physical review letters》2008,100(19):191101
We investigate the influence of magnetic fields upon the dynamics of, and resulting gravitational waves from, a binary neutron-star merger in full general relativity coupled to ideal magnetohydrodynamics. We consider two merger scenarios: one where the stars have aligned poloidal magnetic fields and one without. Both mergers result in a strongly differentially rotating object. In comparison to the nonmagnetized scenario, the aligned magnetic fields delay the full merger of the stars. During and after merger we observe phenomena driven by the magnetic field, including Kelvin-Helmholtz instabilities in shear layers, winding of the field lines, and transition from poloidal to toroidal magnetic fields. These effects not only mediate the production of electromagnetic radiation, but also can have a strong influence on the gravitational waves. Thus, there are promising prospects for studying such systems with both types of waves. 相似文献
964.
The angular distribution of photoelectrons ejected from benzene using 21.22 eV radiation has been measured and the results applied to the analysis of the ionization bands. 相似文献
965.
The vibrations of planar A3B type molecules with D3h symmetry are analysed, by treating these molecules as a special case of A2BC types with C2v symmetry. Analytical expressions for the four normal mode frequencies are derived in terms of four force constants, and optimized values of the latter for the boron trihalides and sulphur trioxide are obtained and briefly discussed. Frequencies of various isotopic species are also calculated. 相似文献
966.
The thermal conductivity of a glassy PdSi alloy has been measured in the temperature range 0.1–30 K. The thermal conductivity contributed by the phonons has the same anomalous behavior as found for all non-metallic amorphous materials. Heat treatment increases the phonon thermal conductance by ~50%, a change which does not appear to be related to partial crystallization. 相似文献
967.
We determine the Green's function for the third-order three-point generalized right focal boundary value problem
968.
D. D. Anderson Muhammad Zafrullah 《Proceedings of the American Mathematical Society》2003,131(12):3689-3692
We show that a weakly Krull domain satisfies : for every pair there is an such that is -invertible. For Noetherian, satisfies if and only if every grade-one prime ideal of is of height one. We also show that a modification of can be used to characterize Noetherian domains that are one-dimensional.
969.
970.