The Experts below are selected from a list of 33213 Experts worldwide ranked by ideXlab platform
A L De Oliveira - One of the best experts on this subject based on the ideXlab platform.
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secondary scattering on the intensity dependence of the Capture Velocity in a magneto optical trap
Physical Review A, 2005Co-Authors: Marcio Rodrigo Loos, S B Massardo, R A De Simone Zanon, A L De OliveiraAbstract:In this work, we consider a three-dimensional model to simulate the Capture Velocity behavior in a sample of cold-trapped sodium atoms as a function of the trapping laser intensity. We expand on previous work [V. S. Bagnato, L. G. Marcassa, S. G. Miranda, S. R. Muniz, and A. L. de Oliveira, Phys. Rev. A 62, 013404 (2000)] by calculating the Capture Velocity over a broad range of light intensities considering the secondary scattering in a magneto-optical trap. Our calculations are in a good agreement with recent measured values [S. R. Muniz et al., Phys. Rev. A 65, 015402 (2001)].
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measuring the Capture Velocity of atoms in a magneto optical trap as a function of laser intensity
Physical Review A, 2000Co-Authors: Vanderlei Salvador Bagnato, S R Muniz, Luis Gustavo Marcassa, S G Miranda, A L De OliveiraAbstract:Using the dark-spot Zeeman-tuned slowing technique, we have measured the Capture Velocity of a magneto-optical trap as a function of the trap laser intensity. The values obtained are in reasonable agreement with calculations based on a simple model. Nevertheless, the dependence of Capture Velocity in the low-intensity regime seems to be slightly different from the predictions. The measurement of this type of trap parameter is of interest in the analysis of exoergic cold collisions, where the knowledge of such values is important for the interpretation of experimental results.
Lingjie Zeng - One of the best experts on this subject based on the ideXlab platform.
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experimental and numerical study of the effect of perimeter jet enhancement on the Capture Velocity of a rectangular exhaust hood
Journal of building engineering, 2021Co-Authors: Jing Zhang, Jian Wang, Jun Gao, Mengxiao Xie, Changsheng Cao, Lingjie ZengAbstract:Abstract Using a radial jet at the outer edge of a circular exhaust hood can effectively reduce the Velocity attenuation in front of the exhaust hood. The Velocity distribution, especially the centerline Velocity, is a key parameter in the effective design and use of an exhaust hood. In this paper, based on the derivation of the prediction formula of the suction Velocity, the study of the suction Velocity of jet-enhanced rectangular exhaust hood that considers the jet enhanced, viscous and geometrical effects is presented via the experimental and numerical methods. To understand the suction Velocity distribution, the centerline Velocity is investigated by varying the jet Velocity, jet angle, jet slot width, exhaust rate and aspect ratio of the hood. It is found that the critical jet Velocity condition is a most effective and energy-saving working condition for this kind of hood. Based on the critical jet Velocity working condition, reducing the jet angle instead of increasing the exhaust rate is an airflow-rate-saving way to further increase the centerline Velocity at a relatively large distance away from the hood opening. Calculation equations for the prediction of the centerline Velocity of rectangular jet-enhanced exhaust hood are proposed. The error of the formula is proven to be within 10%, and its application range is proposed. The outcome of this work can help to efficiently design and use this type of energy-saving exhaust hood in residential and industrial local ventilation applications.
Vanderlei Salvador Bagnato - One of the best experts on this subject based on the ideXlab platform.
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measurements of Capture Velocity in a magneto optical trap for a broad range of light intensities
Physical Review A, 2001Co-Authors: S R Muniz, K M F Magalhaes, Ph W Courteille, M A Perez, Luis Gustavo Marcassa, Vanderlei Salvador BagnatoAbstract:We use a dark-spot Zeeman-tuned slowing technique to measure the Capture Velocity in a sodium magneto-optical trap as a function of the trapping laser intensity. We expand on previous work by measuring the Capture Velocity over a broad range of light intensities. We observe that the Capture Velocity reaches a maximum value and then decreases with increasing light intensities, which might imply a minimum in the trap-loss rate. This observation supports a recently published explanation of the dependence of the trap-loss rates, at low intensities, based mainly on the escape Velocity.
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measuring the Capture Velocity of atoms in a magneto optical trap as a function of laser intensity
Physical Review A, 2000Co-Authors: Vanderlei Salvador Bagnato, S R Muniz, Luis Gustavo Marcassa, S G Miranda, A L De OliveiraAbstract:Using the dark-spot Zeeman-tuned slowing technique, we have measured the Capture Velocity of a magneto-optical trap as a function of the trap laser intensity. The values obtained are in reasonable agreement with calculations based on a simple model. Nevertheless, the dependence of Capture Velocity in the low-intensity regime seems to be slightly different from the predictions. The measurement of this type of trap parameter is of interest in the analysis of exoergic cold collisions, where the knowledge of such values is important for the interpretation of experimental results.
Raymond M. Brach - One of the best experts on this subject based on the ideXlab platform.
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experimental and numerical studies of microsphere oblique impact with planar surfaces
Journal of Aerosol Science, 2000Co-Authors: X Li, Patrick F. Dunn, Raymond M. BrachAbstract:Oblique impact experiments have been carried out with stainless-steel microspheres and silicon surfaces under a range of impact velocities from 0.45 to 1.90 m s−1 and different incident angles. When the normal Velocity component for oblique impact is less than the Capture Velocity as seen for normal impact, no Capture was observed. The experimental results also reveal that the pattern of impulse ratio variation with incident angle varies with different initial impact velocities. Furthermore, the measured coefficient of restitution values can be predicted by a dynamic simulation model, and the measured impulse ratios can be matched if the microspheres are assumed to have initial angular velocities.
Jing Zhang - One of the best experts on this subject based on the ideXlab platform.
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experimental and numerical study of the effect of perimeter jet enhancement on the Capture Velocity of a rectangular exhaust hood
Journal of building engineering, 2021Co-Authors: Jing Zhang, Jian Wang, Jun Gao, Mengxiao Xie, Changsheng Cao, Lingjie ZengAbstract:Abstract Using a radial jet at the outer edge of a circular exhaust hood can effectively reduce the Velocity attenuation in front of the exhaust hood. The Velocity distribution, especially the centerline Velocity, is a key parameter in the effective design and use of an exhaust hood. In this paper, based on the derivation of the prediction formula of the suction Velocity, the study of the suction Velocity of jet-enhanced rectangular exhaust hood that considers the jet enhanced, viscous and geometrical effects is presented via the experimental and numerical methods. To understand the suction Velocity distribution, the centerline Velocity is investigated by varying the jet Velocity, jet angle, jet slot width, exhaust rate and aspect ratio of the hood. It is found that the critical jet Velocity condition is a most effective and energy-saving working condition for this kind of hood. Based on the critical jet Velocity working condition, reducing the jet angle instead of increasing the exhaust rate is an airflow-rate-saving way to further increase the centerline Velocity at a relatively large distance away from the hood opening. Calculation equations for the prediction of the centerline Velocity of rectangular jet-enhanced exhaust hood are proposed. The error of the formula is proven to be within 10%, and its application range is proposed. The outcome of this work can help to efficiently design and use this type of energy-saving exhaust hood in residential and industrial local ventilation applications.