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991.
Event-by-event fluctuations of the average transverse momentum of produced particles near midrapidity have been measured by the PHENIX Collaboration in square root of (sNN)=200 GeV Au+Au, and p+p collisions at the Relativistic Heavy Ion Collider. The fluctuations are observed to be in excess of the expectation for statistically independent particle emission for all centralities. The excess fluctuations exhibit a dependence on both the centrality of the collision and on the pT range over which the average is calculated. Both the centrality and pT dependence can be well reproduced by a simulation of random particle production with the addition of contributions from hard-scattering processes.  相似文献   
992.
We present the sampling theorem with sampling functions of general form for entire functions satisfying one of the growth conditions
  相似文献   
993.
This article extends previous results on the Pompeiu problem with moments. On the Heisenberg group the results previously considered for L2(Hn) have been extended to the function spaces Lp(Hn) for 1 p . In the case of L(Hn), the conclusions recover differential conditions comparable to those observed in the Euclidean space Cn.  相似文献   
994.
Formant discrimination for isolated vowels presented in noise was investigated for normal-hearing listeners. Discrimination thresholds for F1 and F2, for the seven American English vowels /i, I, epsilon, ae, [symbol see text], a, u/, were measured under two types of noise, long-term speech-shaped noise (LTSS) and multitalker babble, and also under quiet listening conditions. Signal-to-noise ratios (SNR) varied from -4 to +4 dB in steps of 2 dB. All three factors, formant frequency, signal-to-noise ratio, and noise type, had significant effects on vowel formant discrimination. Significant interactions among the three factors showed that threshold-frequency functions depended on SNR and noise type. The thresholds at the lowest levels of SNR were highly elevated by a factor of about 3 compared to those in quiet. The masking functions (threshold vs SNR) were well described by a negative exponential over F1 and F2 for both LTSS and babble noise. Speech-shaped noise was a slightly more effective masker than multitalker babble, presumably reflecting small benefits (1.5 dB) due to the temporal variation of the babble.  相似文献   
995.
We applied a finite-difference time domain algorithm to the study of field and intensity correlations in random media. Close to the onset of Anderson localization, we observe deviations of the correlation functions, in both shape and magnitude, from those predicted by the diffusion theory. Physical implications of the observed phenomena are discussed.  相似文献   
996.
The stable monodentate Lindskog type bicarbonate nickel(ii) complex and its isomer have been prepared and fully characterized.  相似文献   
997.
We report measurements of branching fractions for charged and neutral B-->eta(c)K decays where the eta(c) meson is reconstructed in the K(0)(S)K+/-pi(-/+), K+K-pi(0), K(*0)K-pi(+), and pp; decay channels. The neutral B0 channel is a CP eigenstate and can be used to measure the CP violation parameter sin(2phi(1). We also report the first observation of the B0-->eta(c)K(*0) mode. The results are based on an analysis of 29.1 fb(-1) of data collected by the Belle detector at KEKB.  相似文献   
998.
We investigate the energy spectra of clean incommensurate double-walled carbon nanotubes, and find that the overall spectral properties are described by the critical statistics similar to that known in the Anderson metal-insulator transition. In the energy spectra, there exist three different regimes characterized by Wigner-Dyson, Poisson, and semi-Poisson distributions. This feature implies that the electron transport in incommensurate multiwalled nanotubes can be either diffusive, ballistic, or intermediate between them, depending on the position of the Fermi energy.  相似文献   
999.
The Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor permits absolute distance measurement with subnanometer accuracy, an improvement of 4 orders of magnitude over current techniques. The system uses fast phase modulators to resolve the integer cycle ambiguity of standard interferometers. The concept is described and demonstrated over target distances up to 1 m. The design can be extended to kilometer-scale separations.  相似文献   
1000.
The elastic-scattering intensity pattern from a single particle as a function of spherical coordinate angles theta and phi provides detailed information on the pattern's morphology. By use of an ellipsoidal reflector and a CCD camera, a single-laser-shot intensity pattern from a large angular range (theta from 90 degrees to 168 degrees and phi from 0 degrees to 360 degrees) was detected from a single aerosol (e.g., a Bacillus subtilisspore, a 1-microm-diameter polystyrene latex sphere, or a cluster of either of these) flowing through the reflectors focal volume at 5 m/s. Noticeable difference in the large-angle-range two-dimensional angular optical scattering (LATAOS) suggest that the LATAOS pattern could be useful in differentiating and classifying life-threatening aerosols from normal background aerosols.  相似文献   
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